Comprehensive Board Review Flashcards
1
Q
What are Virchow-Robin spaces?
A
Perivascular potential space, between blood vessels and the surrounding sheath of leptomeninges entering the nervous tissue (brain and spinal cord).
2
Q
What ion(s) are increased in CSF compared to plasma?
A
Chloride.
3
Q
What ion(s) are decreased in CSF compared to plasma?
A
Potassium, calcium, uric acid and glucose.
4
Q
Describe Froin’s syndrome.
A
CSF xanthochromia and clotting (due to the presence of fibrinogen) occur when CSF is loculated, usually in the lumbar thecal sac.
CSF protein is increased (up to 1000mg/L).
5
Q
Sites of CSF production?
A
70% choroid plexus, 18% ultrafiltrate, 12% metabolic H20 production.
6
Q
What nuclei controls CSF production?
A
Raphe nuclei send axons (serotonin) to the periependymal vessels.
7
Q
Rate of CSF production.?
A
0.3-0.37mL/min or 20mL/hr.
8
Q
The BBB is formed by what?
A
Capillary endothelial tight junctions (mainly).
Pinocytic activity in endothelial cells.
Astrocytic foot processes.
9
Q
What are the circumventricular organs?
A
- Organum vasculosum (lamina terminalis).
- Neurohypophysis.
- Median eminence of the hypothalamus.
- Subfornical organ.
- Subcommissural organ.
- Pineal gland.
- Area postrema.
10
Q
Functions of the organum vasculosum (lamina terminalis).
A
- Outlet for hypothalamic peptides.
2. Detect peptides, amino acids, and proteins in the blood.
11
Q
Functions of the neurohypophysis.
A
Outlet for hypothalamic hormones (oxytocin and vasopressin).
12
Q
Functions of the median eminence of the hypothalamus.
A
Release hypothalamic-releasing factors.
13
Q
Functions of the subfornical organ.
A
- May be involved in body fluid regulation.
- Located between the foramina of Monro.
- Connected to the choroid plexus.
14
Q
Functions of the subcommissural organ.
A
- Function unknown.
- Located under the posterior commissure.
- The only circumventricular organ with an intact BBB.
15
Q
Functions of the pineal gland.
A
- Melatonin production.
2. Role in circadian rhythm.
16
Q
Functions of the area postrema.
A
- A chemoreceptor that induces emesis when stimulated by digitalis or apomorphine.
- Located on the floor of the 4th ventricle.
- The only paired circumventricular organ.
17
Q
CBF in normal brain tissue.
A
50 mL/100g brain tissue per minute.
18
Q
CBF in the ischemic penumbra (reversible).
A
8-23mL/100g brain tissue per minute.
19
Q
CBF in irreversible neuronal death.
A
<8mL/100g brain tissue per minute.
20
Q
What percentage of the population has a hypoplastic vertebral artery?
A
40%.
21
Q
Intraosseus branches off the C3 segment of the ICA.
A
- Caroticotympanic artery.
- Vidian artery.
- Periosteal arterial branches.
22
Q
Describe a persistent stapedial artery.
A
Embryonic stapedial artery that fails to involute (primitive hyoid branch of the ICA).
Courses from the vertical segment, exits through a bony canal on the cochlear promontory and traverses the footplate of stapes to terminate as the middle meningeal artery.
If present, the foramen spinosum is either small or absent with enlarged geniculate fossa (Y-shaped).
23
Q
Describe a persistent otic artery.
A
Primitive otic artery that fails to involute.
Embryonic carotid-basilar anastomoses.
Connects petrous ICA to embryonic dorsal longitudinal neural arteries.
24
Q
Branches of the intracavernous (C4) ICA.
A
- Meningohypophyseal trunk (posterior trunk).
- Inferolateral trunk (artery of the inferior cavernous sinus).
- Medial trunk (McConnell’s capsular arteries).
25
Branches off the meningohypophyseal trunk.
1. Tentorial artery (of Bernasconi and Cassinari) - supplies tentorium.
2. Inferior hypophyseal artery - supplies neurohypophysis.
3. Dorsal meningeal artery (clival branch) - supples CN VI and part of the clivus.
26
Describe a persistent trigeminal artery.
Most common primitive internal carotid artery-basilar anastomosis.
Associated with higher incidence of vascular abnormalities (25%), aneurysms are most common.
27
Branches of the intracaverous ICA.
1. Ophthalmic.
2. Superior hypophyseal.
3. PCOM.
4. Anterior choroidal.
5. Branches to the hypothalamus, optic nerve and chiasm.
28
Vascular territories of the superior hypophyseal arteries?
They course beneath the optic nerve to supply the pituitary (anterior lobe, pituitary stalk), tuber cinerum, and optic nerve and chiasm (inferior surface).
These arteries anastomose with the arteries of the contralateral as well as the inferior hypophyseal arteries to form the hypophyseal portal system.
29
What is a fetal PCA?
When PCOM diameter is the same as PCA.
Failed regression of fetal PCA leads to dominant blood supply of occipital lobes from the ICA rather than from the vertebrobasilar system.
30
Origin of the anterior choroidal artery.
Posteromedial surface of the ICA, 2-4 mm distal to the PCOMs origin.
31
What are the two segments of the anterior choroidal artery?
1. Cisternal segment - courses posteromedially within the suprasellar cistern beneath the optic tract, then turns posteromedially around the uncus.
2. Intraventricular segment - continues from the cisternal segment. Prior to reaching the lateral geniculate body, it turns posterolaterally through the crural and ambient cisterns to enter the choroidal fissure (plexal point) of the temporal horn.
32
What are the branches of the ACA?
A1 - horizontal/precommunicating segment.
A2 - vertical/postcommunicating segment.
A3 - distal ACA and cortical branches.
33
Branches off the A1 segment?
1-12 perforating arteries called the medial lenticulostriate arteries (medial proximal striate arteries).
Course through the anterior perforated substance to supply the optic nerve (superior surface), optic chiasm, anterior hypothalamus, septum pellucidum, anterior commissure, and pillars of the fornix and anteroinferior striatum.
34
Location of the anterior communicating artery?
Located in hte cistern of the lamina terminalis.
Two or more perforators arise from the Acomm and supply the infundibulum and optic chiasm.
35
Branches off the A2 segment.
1. Recurrent artery of Heubner - arises just proximal (or more commonly just distal) to the ACOM and courses back towards A1.
2. Orbitofrontal artery.
3. Frontopolar artery.
4. Anterior internal frontal artery.
36
Vascular territory of the recurrent artery of Heubner?
Head of the caudate, anterior limb of the IC, anterior putamen and globus pallidus, septal nuclei, and inferior frontal lobe.
37
What are the branches off the A3 segment?
1. Callasomarginal.
2. Pericallosal.
3. Middle internal frontal artery.
4. Posterior internal frontal artery.
5. Paracentral artery.
6. Superior parietal artery.
7. Inferior parietal artery.
38
What are the segments of the MCA?
M1 (horizontal segment).
M2 (insular segment).
M3 (opercular segment).
M4 (cortical segment).
39
What are the branches off the M1 segment?
1. Uncal artery.
2. Temporopolar artery.
3. Anterior temporal artery.
4. Lateral lenticulostriate arteries.
40
What are the branches off the superior trunk of the M2 segment?
1. Orbitofrontal branch.
2. Prefrontal branch.
3. Precentral branch.
4. Central branch.
5. Anterior parietal branch.
41
What are the branches off the inferior trunk of the M2 segment?
1. Posterior parietal branch.
2. Angular branch.
3. Temporooccipital branch.
4. Posterotemporal branch.
5. Middle temporal branch.
42
What are the segments of the PCA?
P1 - precommunicating segment.
P2 - ambient segment.
P3 - quadrigeminal segment.
P4 - terminal cortical branches.
43
What are the branches off the P1 segment?
1. Posterior thalamoperforating arteries.
2. Medial posterior choroidal arteries.
3. Meningeal branches.
44
What are the branches off the P2 segment?
1. Lateral posterior choroidal artery.
2. Thalamogenicular arteries.
3. Cortical branches.
45
What are the branches off the P3 segment?
1. Posterior temporal artery.
2. Internal occipital artery.
3. Parietooccipital artery.
4. Calcarine artery.
5. Posterior pericallosal artery.
46
Branches off the vertebral artery?
1. Extracranial branches (segmental spinal branches, muscular branch anastomoses with muscular branch of ECA, and meningeal branch).
2. Posterior spinal artery.
3. Anterior spinal artery.
4. PICA.
47
What is the blood supply to the falx cerebelli?
1. Posterior meningeal branches.
2. Occipital.
3. Ascending pharyngeal.
4. PICA.
48
Vascular territory of the posterior spinal artery?
Gracile and cuneate fasciculi, ifnerior cerebellar peduncle.
49
Vascular territory of the anterior spinal artery?
Pyramid, medial lemniscus, MLF, olive, vagal and hypoglossal nuclei.
50
What are the segments of PICA?
1. Anterior medullary.
2. Lateral medullary.
3. Tonsillomedullary.
4. Telovelotonsillar.
5. Hemispheric branches.
51
What syndrome occurs with occlusion of PICA?
Lateral medullary syndrome (Wallenberg's).
52
What are the branches off AICA?
1. Internal auditory artery.
2. Recurrent perforating artery.
3. Subarcuate artery.
53
Vascular supply to the striatum?
Mainly: MCA (lenticulostriate arteries).
Rostrally: recurrent artery of Heubner.
Caudally: anterior choroidal.
54
Vascular supply to the internal capsule?
Anterior limb: ACA (Heubner, MCA lateral (lenticulostriate).
Genu: ICA perforators, MCA lateral (lenticulostriate)
Posterior limb: anterior choroidal and Pcomm.
55
Vascular supply to the thalamus?
PCA by way of posterior thalamoperforators, thalamogeniculate arteries, and the medial posterior choroidals.
Rostrally from Pcomm and basilar bifurcation.
56
Vascular supply to the medulla?
Anterior and posterior spinal arteries.
PICA and vertebral arteries.
57
Vascular supply to the pons?
Basilar paramedian branches.
Short and long circumferential branches of the basilar artery that anastomose with AICA at the middle cerebellar peduncle.
SCA.
58
Vascular supply to the midbrain?
Basilar artery, PCA, SCA, Pcomm, and anterior choroidal.
59
What is Weber's syndrome?
CN III palsy with contralateral hemiplegia.
60
What is Benedikt's syndrome?
Weber's plus red nucleus lesion (coarse intentional tremor, hyperkinesias, and ataxia of the upper limb).
61
What cistern does the basal vein of Rosenthal pass through?
Ambient cistern.
62
Excitatory neurotransmitters.
Glutamate and aspartate.
63
Inhibitory neurotransmitters.
GABA.
64
How many layers are in the neocortex?
The neocortex has 6 layers.
65
How many layers are in the allocortex?
The allocortex has 3 layers, located in the olfactory cortex, hippocampus, and dentate gyrus.
66
What are the 6 layers in the neocortex?
```
I. Molecular (most superficial).
II. External granular layer.
III. External pyramidal layer.
IV. Internal granular layer.
V. Internal pyramidal layer.
VI. Multiform.
```
67
What layer of the neocortex is responsible for main sensory input?
Layer IV (internal granular layer).
68
What layer of the neocortex has main efferents to the brainstem and spinal cord?
Layer V (internal pyramidal layer).
69
What layer of the neocortex has efferent fibers to the thalamus?
Layer VI (multiform layer).
70
Function of the premotor cortex (area 6a).
Voluntary motor control for responses dependent on sensory input.
71
Function of the supplemental motor cortex (area 6a).
Programming, planning, and initiation of motor movements.
72
Function of the frontal eye fields.
Initiates saccades - stimulation causes contralateral eye deviation.
73
Contents of the neostriatum (or striatum).
Caudate and putamen.
74
Contents of the paleostriatum.
Globus pallidus.
75
Contents of the corpus striatum.
Neostriatum + paleostriatum (caudate, putamen, GP).
76
Contents of the archistriatum.
Amygdala.
77
Contents of the lentiform nuclei.
Putamen and globus pallidus.
78
Location of lateral medullary lamina.
Between putamen and globus pallidus.
79
Location of medial medullary lamina.
Between medial and lateral globus pallidus.
80
Origin of the adenohypophysis.
Ectoderm.
81
Origin of the neurohypophysis.
Diencephalic.
82
What are the three components of the adenohypophysis?
1. Pars tuberalis
2. Pars intermedia.
3. Pars distalis.
83
What are the three components of the neurohypophysis?
1. Pars nervosa (posterior lobe).
2. Infundibulum.
3. Nuclei (supraoptic and paraventricular).
84
What arteries form the hypophyseal portal system?
The hypophyseal portal system is formed by the superior hypophyseal arteries (supraclinoid ICA) and the inferior hypophyseal arteries (branch of cavernous ICA meningohypophyseal trunk).
85
What are the cholinergic areas of the CNS?
1. Substantia innominata (nucleus basalis of Meynert).
2. Pedunculopontine nucleus.
3. Lateral dorsal tegmental nucleus.
4. Medial habenular nucleus.
86
What is the archicerebellum?
Oldest component which includes the flocculus and nodulus.
Involved with vestibular function.
87
What is the paleocerebellum?
Includes the anterior lobe, rostral to the primary fissure.
Controls muscle tone with inputs from the stretch receptors.
88
What is the neocerebellum?
Newest component which includes the posterior lobe between the primary fissure and the lateral fissures.
Controls coordination with inputs from the contralateral cortex (via pontine relay nuclei).
89
Function of dorsal spinocerebellar tract.
Uncrossed.
Conveys proprioception from the joints, muscle spindles, and Golgi tendon organs of the ipsilateral LEs and upper trunk to Clarke's nucleus in lamina VII of the intermediate zone in the spinal cord.
90
Function of the ventral spinocerebellar tract.
Crossed.
Conveys efferent copies of motor commands that reach the alpha motor neurons and exteroceptive and proprioceptive information for the LEs.
91
What are the cerebellar nuclei and their functions.
1. Fastigial nucleus - vestibular system.
2. Globuse nucleus - tone.
3. Emboliform nucleus - tone.
4. Dentate nucleus - coordination.
92
What nuclei make up the nucleus interpositus?
1. Globus and emboliform nuclei.
93
The olfactory tract carries secondary neurons to what three areas?
1. Primary (lateral) olfactory area (via lateral olfactory stria).
2. Anterior perforated substance (intermediate olfactory area).
3. Medial olfactory area (septal area).
94
What structures make up the primary (lateral) olfactory area?
1. Uncus.
2. Entorhinal area (anteiror portion of the hippocampal gyrus).
3. Limen insula (insular and frontal lobe junction).
4. Part of the amygdala.
95
Function of the medial olfactory area?
1. Located in the subcallosal region of the medial frontal lobe, this region mediates emotional responses to odors with its limbic connections.
96
What is the diagonal band of Broca?
1. Connects all three olfactory areas.
97
What is von Willebrand's knee?
1. Contains fibers from the contralateral optic nerve that travel across a short distance into the other optic nerve before continuing through the optic tract.
98
Function of the lateral subnucleus of CN III?
1. Innervates ipsilateral inferior rectus, inferior oblique, and medial rectus.
99
Function of the medial subnucleus of CN III?
1. Innervates contralateral superior rectus.
100
Function of the central subnucleus of CN III?
1. Innervates levator palpebrae superioris bilaterally.
101
CN III passes through what cistern?
1. Interpeduncular cistern at the midbrain/pons junction.
102
What division of CN III do parasympathetic fibers travel?
1. Inferior division.
103
Function of the mesencephalic nucleus of CN V?
1. Conveys proprioceptor info from the muscles of mastication.
104
Function of the chief sensory nucleus of CN V?
1. Conveys light touch from face.
105
Function of the spinal nucleus of CN V?
1. Conveys pain, temperature, and deep pressure info.
106
Location of the abducens nucleus?
1. Ventral to the 4th ventricle in the pontine tegmentum.
107
Motor branches of CN VII?
1. Ten Zebras Bit My Clock.
Temporal, zygomatic, buccal, mandibular, cervical.
108
Lesion of the lateral lemniscus causes what?
1. Contralateral deafness.
109
Unilateral damage to the superior colliculus produces what?
1. Contralateral visual field neglect.
2. Impaired tracking.
3. NO deficit with eye movements.
110
What is the main function of the rostral interstitial nucleus of the MLF?
1. Main center for vertical eye movement (especially downward).
111
What is the function of the inferior colliculus?
1. Responsible for the tonotopic organization of auditory information and projects via the brachium of the inferior colliculus to the medial geniculate body.
112
What are some functions of the periaqueductal gray?
1. Central analgesia.
2. Vocalization.
3. Control of reproductive behavior.
4. Aggressive behavior.
5. Upward gaze.
113
What happens when the red nucleus is stimulated?
1. Increased tone in the contralateral flexors and decreased tone in the contralateral extensors.
114
What happens when the interposed nucleus is stimulated?
1. Increased ipsilateral flexion.
115
What happens when the pedunculopontine nucleus is stimulated?
1. Causes walking movements.
| 2. Controls locomotion.
116
What neurotransmitter is predominant in the locus ceruleus?
1. NE.
117
What is the function of the locus ceruleus?
1. Controls cortical activation and paradoxical (REM) sleep.
118
What are the functions of the raphe nuclei?
1. Provided endogenous analgesia via the substantia gelatinosa.
2. Controls deep sleep, mood, and aggression.
119
Features of Rexed lamina I?
1. Mainly pain and temperature (fast pain, A-delta), that travel in the contralateral spinothalamic tract.
120
What is another term for Rexed lamina II?
1. Substantia gelatinosa.
121
Function of Rexed lamina II?
1. Slow pain (C fibers).
122
What is another term for rexed lamina III/IV?
1. Nucleus proprius.
123
Function of rexed lamina III/IV?
1. Contains interneurons that convey low intensity stimuli to the thalamus.
124
What is another term for rexed lamina VII?
1. Zona intermedia.
125
What type of neurons are found in rexed lamina IX?
1. Alpha and gamma motor neurons.
126
What is the function of the medial nuclear group of rexed lamina IX?
1. Controls the axial muscles.
127
What is the function of the lateral nuclear group of rexed lamina IX?
1. Controls the limbs appendicular muscles.
128
What is the function of the ventral nuclear group of rexed lamina IX?
1. Controls extensors.
129
What is the function of the dorsal nuclear group of rexed lamina IX?
1. Controls flexors.
130
Function of the posterior columns?
1. Convey fine touch, vibration and proprioception.
131
Function of the anterior spinothalamic tract?
1. Conveys mainly light touch.
132
Function of the lateral spinothalamic tract?
1. Conveys pain and temperature.
133
Function of the spinotectal tract?
1. May convey pain stimuli.
134
Function of the dorsal spinocerebellar tract?
1. Conveys touch, pressure and proprioception from the lower limbs.
135
Function of the ventral spinocerebellar tract?
1. Conveys lower limb posture and coordination information.
136
Function of the cuenocerebellar tract?
1. Conveys touch, pressure, and proprioception from the upper limbs (upper limb equivalent of the dorsal spinocerebellar tract).
137
Function of the spinoreticular tract?
1. Modulates motor, sensory, behavior and awareness.
138
Function of the corticospinal tract?
1. Conveys voluntary skilled movements.
139
Function of the tectospinal tract?
1. Conveys reflex posture movements in response to visual and possibly auditory stimuli.
140
Function of the rubrospinal tract?
1. Involved in the maintenance of flexor tone.
141
Function of the vestibulospinal tract?
1. Involved in the maintenance of extensor tone.
142
Function of the pontine reticulospinal tract?
1. Involved in the maintenance of extensor tone (antigravity muscles).
2. Axial (especially the neck muscles) limb muscles.
143
Function of the medullary reticulospinal tract?
1. Involved in inhibition of extensor tone.
144
What tracts are involved in flexor tone?
1. Lateral reticulospinal (medullary tract).
| 2. Rubrospinal tract (to upper limbs only).
145
What tracts are involved in extensor tone?
1. Medial and lateral vestibulospinal tracts.
| 2. Medial (pontine) reticulospinal tract.
146
Damage to the anterior lobe of the cerebellum causes what?
1. Removes tonic inhibition of the lateral vestibular nucleus resulting in increased extension.
147
Normal AP diameter of the spinal canal at C1-C2?
1. 15 mm.
148
Normal AP diameter of the spinal canal at C3-T12?
1. 12 mm.
149
Normal AP diameter of the spinal canal at L1-L5?
1. 15-20 mm.
150
Structures within the cribiform plate?
1. Olfactory nerves.
2. Ethmoidal nerves.
3. Ethmoidal arteries.
151
Structures within the optic canal?
1. CN II
| 2. Ophthalmic artery.
152
Structures within the superior orbital fissure.
1. CNs III, IV, and VI.
2. CN V1 -all three branches (nasociliary, frontal, lacrimal).
3. Sympathetic fibers from ICA plexus.
4. Middle meningeal artery (orbital branch).
5. Lacrimal artery (recurrent meningeal branch).
6. Superior ophthalmic vein.
153
Structures within the inferior orbital fissure.
1. CN V2.
2. Zygomatic nerve.
3. Maxillary nerve (pterygopalatine branch).
4. Infraorbital artery and vein.
5. Inferior ophtlamic vein.
154
Structures within the foramen rotundum.
1. CN V2.
155
Structures within the foramen ovale.
1. CN V3.
| 2. Lesser superficial petrosal nerve.
156
Structures within the foramen lacerum.
1. Usually nothing, 30% with vidian artery.
| 2. ICA traverses upper portion.
157
Structures within the carotid canal.
1. Sympathetic nerves.
| 2. ICA.
158
Structures within the internal acoustic meatus.
1. CN VII, VIII.
| 2. Labyrinthine vessels.
159
Structures within the stylomastoid foramen.
1. CN VII.
| 2. Stylomastoid artery.
160
Structures within the jugular foramen (pars nervosa).
1. CN IX.
| 2. Jacobson's nerve.
161
Structures within the jugular foramen (pars venosa).
1. Posterolateral CN X, XI.
2. Arnold's nerve.
3. Internal jugular vein.
4. Inferior petrosal sinus.
5. Posterior meningeal artery.
162
Structures within the hypoglossal canal.
1. CN XII.
| 2. Posterior meningeal artery.
163
Structures within the foramen cecum.
1. Emissary veins (SSS -> frontal sinus and nose).
2. Anterior falcine artery.
Located between the frontal crest and crista galli.
164
Structures within the supraorbital foramen.
1. CN V1.
| 2. Supraorbital vessels and nerve.
165
Structures within the infraorbital foramen.
1. CN V2.
| 2. Infraorbital vessels and nerve.
166
Structures within the mandibular foramen.
1. CN V3: inferior alveolar nerve.
167
Structures within the incisive foramen.
1. CN V2: nasopalatine nerve.
| 2. Vessels to anterior hard palate.
168
Structures within the mental foramen.
1. CN V3: mental nerve.
169
Structures within the greater palatine foramen.
1. Greater palatine nerves.
2. Vessels to the hard palate and gingiva.
3. Located medial to the third molar.
170
Structures within the lesser palatine foramen.
1. Lesser palatine nerves.
| 2. Vessels to the soft palate.
171
Structures within the pterygopalatine fossa.
1. CN V2: maxillary nerve.
2. Pterygopalatine ganglion.
3. Vidian nerve.
172
Structures within the infratemporal fossa.
1. CN V3.
2. Chorda tympani nerve.
3. Otic ganglion, inferior.
4. Inferior alveolar nerve.
5. Lingual nerve.
6. Buccal nerve.
7. Muscles: temporalis, medial and lateral pterygoids.
8. Maxillary artery.
9. Pterygoid venous plexus.
173
Structures within the vidian canal (pterygoid canal).
1. Vidian nerve.
2. Union between the greater superficial petrosal nerve (parasympathetic) and deep petrosal nerve (sympathetic).
Located at the base of medial pterygoid plate (sphenoid bone).
Connects the foramen lacerum to the pterygopalatine fossa.
174
Structures within the petrotympanic fissure.
1. Transmits chorda tympani.
175
Structures within the greater petrosal foramen.
1. Greater superficial petrosal nerve.
176
Structures within the lesser petrosal foramen.
1. Lesser superficial petrosal nerve.
177
Description of the falciform ligament.
1. Dura extending between anterior clinoid and planum sphenoidale, covering the optic nerve.
178
Description of Liliequist's membrane.
1. Two sleeves of arachnoid connecting the posteroinferior wall of the ICA cistern and the superior aspect of the interpeduncular cistern.
179
What structures pass above the annulus of Zinn?
1. CN V1: lacrimal nerve.
2. CN V1: frontal nerve.
3. CN IV.
180
What structures pass through the annulus of Zinn?
1. CN III: superior division.
2. CN III: inferior division.
3. CN VI: nasociliary nerve.
4. CN VI.
181
What does the superior division of CN III innervate?
1. Levator palpebrae superioris and superior rectus.
182
What does the inferior division of CN III innervate?
1. Inferior rectus, medial rectus and inferior oblique.
183
Feature of the medial longitudinal fasciculus.
1. Eye movements with vestibular input.
184
Feature of the dorsal longitudinal fasciculus.
1. Periventricular hypothalamus and mammillary bodies to midbrain central gray.
185
Feature of the medial lemniscus.
1. Posterior column continuation to the thalamus.
186
Feature of the lateral lemniscus.
1. Part of the auditory pathway.
187
Feature of the commissure of Probst.
1. Connects the nuclei of the lateral lemniscus.
188
Feature of the central tegmental tract.
1. Connects the gustatory nucleus (rostral nucleus solitarius) to medial thalamic VPM (wakefulness).
2. Connects red nucleus to inferior olive.
189
Feature of the medial forebrain bundle.
1. Connects septal area, hypothalamus, basal olfactory areas, hippocampus/subiculum to midbrain, pons and medulla.
190
Feature of the lamina terminalis.
1. Closed rostral end of the neural tube.
191
Feature of the stria terminalis.
1. Connects amygdala to hypothalamus.
192
Feature of the stria medullaris.
1. Connects the septal area, hypothalamus, olfactory area and anterior thalamus to habenulum.
193
Feature of the fornix.
1. Connects hippocampus to:
A. Pre-commissural - septal nuclei, hypothalamus, mammillary bodies, an anterior thalamus.
B. Post-commissural - cingulate gyrus.
194
Feature of the ansa lenticularis.
1. GP interna to thalamus (goes AROUND the internal capsule).
195
Feature of the lenticular fasciculus FFH2.
1. GP interna to thalamus (goes THROUGH the internal capsule).
196
Feature of the thalamic fasciculus FFH1.
1. Combination of ansa lenticularis, lenticular fasciculus, and cerebellothalamic tract to VA and VL of the thalamus.
197
Feature of the mammillothalamic tract.
1. Connects mammillary body to anterior thalamic nucleus.
198
Feature of the fasciculus retroflexus.
1. Connects habenulum to midbrain and interpeduncular nuclei.
199
Feature of the diagonal band of Broca.
1. Connects septal nuclei to amygdala.
200
What covers the corpus callosum?
1. Covered with indusium griseum, which contains medial and lateral longitudinal striate that connects the medial olfactory area with hippocampus.
201
Feature of the tapetum.
1. Fibers in the corpus callosum that connect the temporal and occipital lobes.
202
Feature of the uncinate fasciculus.
1. Connects anterior temporal lobe to orbitofrontal gyrus.
203
Feature of the arcuate fasciculus.
1. Connects the frontal, parietal and temporal lobe (Wernicke's area to Broca's area).
204
Feature of the anterior portion of the anterior commissure.
1. Connects the two olfactory bulbs.
205
Feature of the posterior portion of the anterior commissure.
1. Connects the two inferior and middle frontal gyri, putamen, GP, external capsules and claustrum.
206
Feature of the inferior collicular commissure.
1. Connects the inferior colliculus.
207
Feature of the posterior commissure.
1. Crossing fibers from the pretectal nucleus for the light reflex.
208
Feature of the trapezoid body.
1. Connects ventral cochlear nuclei to contralateral superior olive.
209
What is another term for the superior cerebellar peduncle?
1. Brachium conjunctiva.
210
What is another term for the middle cerebellar peduncle?
1. Brachium pontis.
211
What is another term for the inferior cerebellar peduncle?
1. Restiform and juxtarestiform bodies.
212
Functions of the medial geniculate body?
1. Auditory relay nucleus.
213
Functions of the lateral geniculate body?
1. Visual relay nucleus.
214
Functions of the superior colliculus?
1. Coordination of head/eye movements with visual system.
215
Functions of the inferior colliculus?
1. Auditory relay and processing.
216
Functions of the superior olive?
1. Auditory relay and processing.
217
Functions of the inferior olivary complex?
1. Cerebellar input.
218
Functions of the ciliary ganglion?
1. Parasympathetic from oculomotor nerve.
219
Functions of the gasserian ganglion (semilunar ganglion)?
1. Trigeminal nerve.
220
Functions of the geniculate ganglion?
1. Sensation and taste from facial nerve.
221
Functions of the sphenopalatine ganglion?
1. Lacrimal and nasal glands from the facial nerve.
222
Functions of the submandibular ganglion?
1. Submandibular and sublingual glands from facial nerve.
223
Functions of the spiral ganglion?
1. Hearing to the cochlear nerve.
224
Functions of the superior and inferior vestibular ganglion?
1. Utricle - superior ganglion.
| 2. Saccule - inferior ganglion.
225
Functions of Scarpa's ganglion?
1. Vestibular function.
226
Functions of the otic ganglion?
1. Parotid secretion from glossopharyngeal nerve.
227
Functions of the inferior ganglion of CN IX (petrosal)?
1. Taste.
| 2. Carotid body/sinus - CN IX.
228
Functions of the superior ganglion of CN IX?
1. Ear sensation.
229
Functions of the inferior ganglion of CN X (nodose)?
1. Taste and visceral sensation
230
Functions of the superior ganglion of CN X (jugular)?
1. Ear sensation.
231
Mechanism of action of tetrodotoxin?
1. Blocks voltage-gated Na channels.
232
Mechanism of action of tetraethylammonium (TEA)?
1. Blocks voltage-gated K channels.
233
What are the four classes of small molecule neurotransmitters?
1. Class 1 - ACh
2. Class 2 - amines (NE, epi, dopamine, serotonin)
3. Class 3 - amino acids (GABA, glycine, glutamate, aspartate)
4. Class 4 - NO
234
Function and locations of acetylcholine?
1. Usually excitatory.
2. Found in the motor cortex, skeletal muscle, pre-ganglionic autonomic nerves, post-ganglionic parasympathetic nerves, and post-ganglionic sympathetic nerves supplying sweat glands.
235
Function and locations of norepinephrine?
1. Usually excitatory.
| 2. Found in the pontine locus ceruleus and post-ganglionic sympathetic nerve fibers.
236
Function and locations of dopamine?
1. Inhibitory.
| 2. Found in the neurons of the substantia nigra that project to the putamen and caudate.
237
Function and locations of glycine?
1. Inhibitory.
| 2. Found in the spinal cord (Renshaw cells).
238
Function and locations of GABA?
1. Inhibitory.
| 2. Found in the cortex, basal ganglia, cerebellum (Purkinje cells), and spinal cord.
239
Function and locations of glutamate?
1. Excitatory.
| 2. Found in the cortex, dentate gyrus of the hippocampus, striatum, and cerebellar granule cells.
240
Function and locations of serotonin?
1. Inhibitory.
2. Found in brainstem nucleu (median raphe nuclei) that project to the hypothalamus and spinal cord (dorsal horns) as well as the pineal gland.
241
Locations of nicotinic ACh receptors?
1. Located in the NMJ and pre-ganglionic endings of both sympathetic and parasympathetic fibers.
242
Locations of muscarinic ACh receptors?
1. Located in the post-ganglionic parasympathetic endings and post-ganglionic sympathetic endings innervating sweat glands.
243
Function of the GABA-A receptor?
1. Increases Cl channel permeability.
244
Function of the GABA-B receptor?
1. Increases K conductance.
245
Mechanism of action of barbiturates?
1. Prolong the duration of Cl channel opening.
246
Mechanism of action of benzodiazepines?
1. Increase the frequency of Cl channel opening.
247
Function of free nerve endings?
1. Respond to pain, touch and pressure.
248
Function of Meissner corpuscles?
1. Respond to touch.
249
Function of Merkel disks?
1. Respond to touch and pressure.
250
Function of Pacinian corpuscles?
1. Respond to vibration.
251
Function of Ruffini end organs?
1. Respond to heavy touch and pressure.
252
What are the two types of anterior motor neurons?
1. Alpha motor neurons - innervate skeletal muscle by sending alpha-type A fibers to large skeletal muscle fibers within the motor unit.
2. Gamma motor neurons - relay gamma-type A fibers to intrafusal fibers of the muscle spindle.
253
What is the difference between spasticity and rigidity?
1. Spasticity is characterized by unidirectional resistance to change, velocity dependency, and increased reflexes.
2. Rigidity is characterized by bidirectional resistance to change, is not velocity dependent, and is not associated with hyper-reflexia.
254
When does the anterior neuropore close?
1. 24 days.
255
When does the posterior neuropore close?
1. 26 days.
256
What problems can occur if dysjunction occurs too early?
1. Mesenchyme can enter the neural tube and form lipomas or lipomyelomeningoceles.
257
Defects in secondary neurulation cause what?
1. Spinal dysraphism below L1/2.
258
Defects during ventral induction produce what conditions?
1. Holoprosencephaly.
2. Septo-optic dysplasia.
3. Dandy-Walker malformation.
259
Problems during cellular migration cause what conditions?
1. Callosal agenesis.
2. Schizencephaly.
3. Heterotopias.
260
At what age does the metopic suture close?
1. Around the first year of life.
261
At what age does the anterior fontanelle close?
1. By 2.5 years of life.
262
At what age does the posterior and sphenoid fontanelles close?
1. By 2-3 months of life.
263
At what age does the mastoid fontanelle close?
1. By 1 year of life.
264
What is Meckel-Gruber syndrome?
1. Associated with maternal hyperthermia on days 20-26 of gestation.
2. Associated with cystic dysplastic kidneys, cardiac anomalies, orofacial clefting, and cephaloceles.
265
What is arrhinencephaly?
1. Absence of the olfactory bulbs and tracts with normal cortex and gray matter in place of the corpus callosum.
2. It is associated with holoprosencephaly and Kallman syndrome (anosmia, hypogonadism, and MR).
266
What is colpocephaly?
1. Dilated occipital horns associated with agenesis of the corpus callosum and periventricular leukomalacia, MR and seizures.
267
Features of Trisomy 13 (Patau syndrome)?
1. Hypotelorism.
2. Holoprosencephaly.
3. Microcephaly.
4. Micropthalmia.
5. Cleft palate and lip.
6. Polydactyly.
7. Dextrocardia.
8. Ocular abnormalities.
268
Features of Trisomy 18 (Edward syndrome)?
1. Gyral dysplasia.
2. Callosal agensis.
3. Chiari II.
4. Dolichocephaly.
5. Cerebellar hypoplasia.
6. Hypertelorism.
7. Microphthalmia.
8. Syndactyly.
9. Rocker bottom feet.
10. Ventricular septal defects.
269
Features of 5p deletion (cri-du-chat syndrome)?
1. MR.
2. Microcephaly.
3. Hypertelorism.
4. Congenital heart disease.
270
Features of 15q deletion (Prader-Willi)?
1. MR.
2. Truncal obesity.
3. Short stature.
4. Hypogonadism.
271
What locations are affected with kernicterus?
1. Affects predominantly the GP, thalamus, subthalamus, and CNs III and VIII nuclei causing symmetric cell loss with extrapyramidal motor signs.
2. This is caused by increased unbound unconjugated bilirubin staining the gray matter and causing neuronal necrosis.
272
What is porencephaly?
1. A cavity that extends from the leptomeninges to the ventricles or superficial white matter lined by white matter (as opposed to schizencephaly, which is a cleft lined by gray matter).
273
What is hydranencephaly?
1. Most of the cortex is replaced by CSF.
274
Most common pathogen resulting in a brain abscess?
1. Streptococcus.
275
What are the pathologic states of a cerebral abscess?
1. Early cerebritis (up to 5 days).
2. Late cerebritis (5 days to 2 weeks).
3. Early capsule formation (2-3 weeks).
4. Late capsule formation (> 3 weeks).
276
What is Gradenigo syndrome?
1. Petrous apex osteomyelitis with CN VI palsy and retroorbital pain and may occur in children from extension of severe otitis.
277
Characteristics of lepromatous form of leprosy?
1. Lesions are located in the skin on cooler parts of the body (hands, feet, head, peripheral nerves, anterior eyes, upper airways and testes).
278
Characteristics of tuberculoid form of leprosy?
1. Areas of hypesthetic skin, inflamed swollen nerves, caseating granulomas.
279
What are the 4 types of neurosyphilis?
1. Meningovascular syphilis (lues).
2. General paresis of the insane.
3. Tabes dorsalis.
4. Congenital syphilis.
280
Neurologic complications of Lyme disease?
1. Erythema migrans (70%).
2. Aseptic meningitis.
3. Cranial neuritis (especially CN VII).
4. Encephalitis.
5. Myelopathy.
6. Radiculopathy.
7. Peripheral neuropathy.
281
Most common CNS fungal infection?
1. Candidiasis.
282
Histological features of HSV infections?
1. Cowdry type A inclusions (intranuclear eosinophilic masses with a surrounding halo) found in neurons, oligodendrocytes, and astrocytes.
283
Histological features of CMV infections?
1. Also produces Cowdry type A inclusions (as in HSV) and intracytoplasmic inclusions.
284
What is Ramsay Hunt syndrome?
1. Herpes infection of the geniculate ganglion.
2. May cause dysfunction of CN VII with altered sensation of taste, facial weakness, and vesicular eruptions on the pinna and in the external auditory canal.
285
Histological feature of rabies infections?
1. Negri bodies (intracytoplasmic eosinophilic collections of ribonucleoproteins) are seen in 80% of cases and are especially predominant in the cerebellum (Purkinje cells), brainstem and hippocampus.
286
What is Gerstmann-Strasuller syndrome?
1. Prion disease that can be autosomal dominant or sporadic.
2. Kuru plaques are seen in the cerebellum.
3. Presents with ataxia, dysarthria, hyporeflexia, and cognitive decline without myoclonus.
287
What is fatal familial insomnia?
1. Prion disease characterized by thalamic atrophy.
| 2. Presents with sleep disturbance, agitation, mild cognitive changes, and dysautonomia.
288
What is the most frequent congenital CNS infection?
1. CMV.
289
Presentation of congenital CMV?
1. Hepatosplenomegaly, jaundice, thrombocytopenia, chorioretinitis, seizures, MR, optic atrophy, impaired hearing, and hydrocephalus.
290
Radiographic findings of CMV?
1. May demonstrate microcephaly and periventricular eggshell calcifications.
291
What is the classic triad of congenital toxoplamosis infection?
1. Hydrocephalus.
2. Bilateral chorioretinitis.
3. Cranial calcifications.
292
Presentation of congenital rubella?
1. Chorioretinitis, cataracts, glaucoma, micropthalmia, microcephaly, MR, and deafness.
293
Presentation of congenital syphilis?
1. Hutchinson triad of dental disorders, bilateral deafness, and interstitial keratitis.
294
What tumors stain positive for chromogranin?
1. Pituinary adenoma.
295
What tumors stain positive for common leukocyte antigen?
1. Lymphoma.
| 2. Germinoma.
296
What tumors stain positive for cytokeratin?
1. Carinoma.
2. Craniopharyngioma.
3. Chordoma.
297
What tumors stain positive for desmin?
1. Rhabdosarcoma.
| 2. Teratoma.
298
What tumors stain positive for immunoglobulins kappa and lambda chains?
1. Lymphomas.
299
What tumors stain positive for neurofilament and synaptophysin?
1. Ganglioglioma.
| 2. PNET.
300
What tumors stain positive for S100?
1. Schwannoma.
2. Neurofibroma.
3. PNET.
4. Chordoma.
5. Melanoma.
6. Renal cell carcinoma.
301
What tumors stain positive for synpatophysin?
1. Tumors with neurons (ganglioglioma, central neurocytoma, etc).
302
What tumors stain positive for transthyretin?
1. Choroid plexus tumors.
303
What tumors stain positive for vimentin?
1. Meningioma.
304
Characteristics of limbic encephalitis?
1. Associated with testicular or lung cancer and anti-Ma protein antibodies.
2. Affects medial temporal lobes, cingulate gyrus, and insula.
3. Usually bilateral hyperintense lesions on T2.
4. Presents with memory impairment and AMS.
305
What condition is associated with anti-Yo antibodies?
1. Cause cerebellar degeneration and are associated with ovarian and breast cancer.
306
What condition is associated with anti-Hu antibodies?
1. Associated with oat cell pulmonary carcinoma or lymphoma.
| 2. Cause sensory neuropathy, encephalitis, and cerebellar degeneration.
307
What condition is associated with anti-Ri antibodies?
1. Associated with breast cancer.
| 2. Causes opsoclonus.
308
What condition is associated with antibodies to glutamic acid decarboxylase?
1. Stiff man syndrome - involuntary muscles spasms and rigidity.
309
What is the second most common pediatric brain tumor?
1. Juvenile pilocytic astrocytoma.
310
Common locations for juvenile pilocytic astrocytomas?
1. Cerebellum.
2. Brainstem.
3. Optic pathway.
4. Infundibulum.
311
Histologic buzzword for pilocytic astrocytomas?
1. Rosenthal fibers.
312
Common presentation and location of pleomorphic xanthoastrocytomas?
1. Usually superficial and involve the cortex and leptomeninges but the dura (temporal lobe predominance).
2. Seizures are frequent.
313
Common presentation and location of subependymal giant cell astrocytomas?
1. Located near the foramen of Monro.
2. Present with hydrocephalus and seizures.
3. Seen in 15% of patients with tuberous sclerosis.
314
Treatment of optic gliomas?
1. If distal to the chiasm, remove optic nerve and attached globe.
2. If the chiasm is involved, resect up to the chiasm preserving vision in the better eye and consider radiation if tumor progression is noted.
315
What factor is associated with a better response to chemotherapy in oligodendrogliomas?
1. Combined loss of heterozygosity of chromosomes 1p and 19q (the most common genetic alteration in oligodendrogliomas) is associated with a better response to chemotherapy and improved progression free and overall survival in patients with anaplastic oligodendroglioma.
316
Common locations for ependymomas?
1. Usually infratentorial (may grow from the 4th ventricle out through the foramen of Luschka and Magendie).
2. Also account for 60% of intramedullary spinal cord tumors, occurring mostly at the filum.
317
Common locations for subependymomas?
1. Usually located in the floor of the inferior 4th ventricle or the lateral ventricle.
318
Common locations for choroid plexus papillomas?
1. 50% are located in the lateral ventricle (more commonly left atrium in children).
2. 40% are in the 4th ventricle (more commonly in adults).
319
Characteristics of desmoplastic infantile ganglioglioma?
1. Usually occur before 18 months.
2. Frontal, cystic lesions adherent to the dura with a desmoplastic reaction.
3. Can be differentiated from meningioma because it is GFAP positive and EMA negative.
320
Common location of central neurocytomas?
1. Usually originates at the septum pellucidum and occurs in the lateral and third ventricles near the Foramen of Monro.
321
What tumors have true "ependymal" rosettes?
1. Most commonly seen in ependymomas.
322
What tumors have Homer Wright rosettes?
1. Most commonly seen in medulloblastoma and neuroblastoma as well as pineocytoma.
323
What tumors have Flexnor-Wintersteiner rosettes?
1. Most commonly seen in retinoblastomas and pineoblastomas.
324
Common locations for hemangioblastomas?
1. The most common locations are cerebellar hemispheres or vermis (80%), cervical spinal cord (10%) and brainstem (3%).
325
What tissue are craniopharyngiomas derived from?
1. Derived from squamous cells from the Rathke cleft.
326
What is trilateral retinoblastoma?
1. Bilateral retinoblastomas with a pineoblastoma.
327
What is the most common cause of a tumor in the suprasellar and pineal regions?
1. Germinoma.
328
Most common pineal tumor?
1. Germinoma.
329
Second most common pineal tumor?
1. Teratoma.
330
What tumor has elevated serum AFP and Schiller-Duval bodies?
1. Yolk sac tumor (endodermal sinus tumor).
331
Common locations for chordoma?
1. 40% occur in the clivus and 60% in the sacrum.
332
What tissue are chordomas derived from?
1. Derived from notochord remnants (as is the nucleus pulposus).
333
What stains are positive in chordomas?
1. Positive for cytokeratin and EMA and S100 (mesenchymal, neural crest).
334
What tumors have Russell bodies?
1. Plasmacytoma.
335
Common location for colloid cysts?
1. Normally in the anterior roof of the third ventricle between the columns of the fornices and is frequently attached to the stroma of the choroid.
336
Common locations for arachnoid cysts?
1. Middle fossa (60%).
2. Suprasellar (10%).
3. Quadrigeminal cistern (10%).
4. Posterior fossa (10%, CPA and cisterna magna).
5. Convexity (5%).
337
What is cavum septum pellucidum?
1. At the level of the caudate head.
| 2. CSF is in between the sheets of the septum pellucidum in the lateral ventricles.
338
What is cavum vergae?
1. A posterior continuation of the cavum septum pellucidum.
339
What is cavum velum interpositum?
1. In the third ventricle because of failure of fusion of the tela choroidea.
340
Schwann cells are derived from what tissue?
1. Neural crest cells.
341
Positive stains for cutaneous neurofibroma?
1. Vimentin, Leu7, S100, and occasionally GFAP.
342
DDx for posterior third ventricle tumors?
1. Meningioma.
2. Choroid plexus papilloma.
3. Metastatic tumor.
343
DDx for tectal tumors?
1. Low grade astrocytoma.
344
DDx for primary septum pellucidum tumors?
1. Astrocytoma.
2. Lymphoma.
3. Germinoma.
345
DDx for frontal horn/septum pellucidum tumors?
1. Central neurocytoma.
2. Giant cell astrocytoma.
3. Subependymoma.
346
DDx for frontal horn tumors in children?
1. Low grade astrocytoma.
| 2. Giant cell astrocytoma.
347
DDx for tumors in the body of the ventricle in children?
1. PNET.
| 2. Astrocytoma.
348
DDx for tumors in the atrium of the ventricle in children?
1. Choroid plexus papilloma.
2. Ependymoma.
3. Astrocytoma.
349
DDx for tumors in the occipital and temporal horns in children?
1. Meningioma (rare).
350
DDx for foramen of Monro tumors in children?
1. Giant cell astrocytoma.
2. Colloid cyst.
3. Craniopharyngioma.
351
DDx for anterior third ventricle tumors in children?
1. Astrocytoma.
2. Histiocytosis (hypothalamic/infundibular).
3. Germinoma.
4. Craniopharyngioma (extrinsic).
352
DDx for fourth ventricular tumors in children?
1. Pilocytic astrocytoma.
2. Medulloblastoma.
3. Ependymoma.
4. Exophytic brainstem glioma.
353
DDx for frontal horn tumors in adults?
1. High grade astrocytoma.
2. Giant cell astrocytoma.
3. Central neurocytoma.
4. Subependymoma.
354
DDx for ventricular body tumors in adults?
1. Astrotycoma.
2. Central neurocytoma.
3. Oligodendroglioma.
4. Subependymoma.
355
DDx for ventricular atrium tumors in adults?
1. Meningoima.
2. Metastatic tumor.
3. Lymphoma.
356
DDx for occipital and temporal horn tumors in adults?
1. Meningioma.
357
DDx for foramen of Monro tumors in adults?
1. High grade astrocytoma.
2. Central neurocytoma.
3. Oligodendroglioma.
4. Subependymoma.
5. Colloid cyst.
358
DDx for anterior third ventricle lesions in adults?
1. Colloid cyst.
2. Suprasellar extension of pituitary tumor.
3. Aneurysm.
4. Glioma.
5. Sarcoid.
6. Germinoma.
359
DDx for CPA lesions?
1. Vestibular Schwannoma.
2. Meningioma.
3. Epidermoid.
4. Other (vascular lesions such as dolichoectasia of the basilar artery, aneurysm, AVM, and metastatic tumors.)
360
DDx for internal auditory canal masses?
1. Vestibular schwannoma.
2. Post-operative fibrosis.
3. Neuritis (Bell palsy and Ramsay-Hunt zoster otitis).
361
DDx for temporal bone lesions involving the CPA?
1. Gradenigo syndrome (osteomyelitis of the petrous apex with CN VI palsy, otorrhea, and retroorbital pain).
2. Malignant external otitis.
3. Cholesteatoma.
4. Paraganglioma (globus tympanicum tumor).
362
Presentation of Wyburn-Mason syndrome?
1. Unilateral cutaneous vascular nevi of the face and trunk with retinal, optic nerve, visual pathway and midbrain AVMs.
363
Presentation of Klippel-Trenaunay-Weber syndrome?
1. Angioosteohypertrophy (overgrowth of vessels and bones).
2. One limb is usually enlarged.
3. It is associated with leptomeningeal AVMs and dermatomal cutaneous hemangiomas.
364
Presentation of epidermal nevus syndrome?
1. Ipsilateral nevus and bone thickening associated with MR, seizures, hemiparesis, and gyral malformations.
365
What is Marchiafava-Bignami disease?
1. Demyelination and necrosis of the genu and body of the corpus callosum.
2. Symptoms include dementia, depression, apathy and delusions.
366
Symptoms of arsenic toxicity?
1. Encephalopathy, peripheral neuropathy, abdominal pain, nausea, vomiting, diarrhea, shock.
367
What nerve is commonly affected in lead toxicity?
1. Radial nerve leading to wrist drop.
368
Symptoms of manganese toxicity and what location is affected?
1. Causes Parkinonsian symptoms, psychologic disorders and headache.
2. Neuronal loss and gliosis in the pallidum and striatum.
369
Symptoms of Wernicke's encephalopathy?
1. Conjugate gaze and lateral rectus palsies, nystagmus, gait ataxia, and confusion.
370
What locations are affected in Wernicke's encephalopathy?
1. It affects the mamillary bodies, mediodorsal nucleus of the thalamus, periaqueductal gray, floor of the fourth ventricle (dorsal motor nuclei of X and the vestibular nuclei), and superior cerebellar vermis.
2. The gaze palsies are related to CNs III and VI nuclei lesions, nystagmus to vestibular nuclei lesions, and ataxia to superior cerebellar vermian lesions.
371
Symptoms of Korsakoff psychosis?
1. Deterioration in retrograde and anterograde memory, unintentional confabulation.
372
What locations are affected in Korsakoff's psychosis?
1. Lesions are in the dorsomedial thalamus.
373
What is the MOA of tetanus toxin?
1. It produces presynaptic excitation of agonist and antagonist muscles (especially the masseter causing lockjaw or trismus) by inhibiting the neurotransmitter release of glycine from inhibitory interneurons such as Renshaw cells in the spinal cord.
2. Tetanus toxin specifically cleaves synaptobrevin.
374
What other conditions are similar to tetanus?
1. Strychnine poisoning.
2. Black widow spider bite.
3. Stiff-man syndrome.
375
Symptoms of diptheria toxin?
1. Causing ascending paralysis and cardiomyopathy.
2. It is distinguished by early bulbar and ciliary dysfunction and delayed symmetric sensorimotor peripheral neuropathy with demyelination.
376
MOA of the botulism exotoxin?
1. Causes presynaptic inhibition at the neuromuscular junction by decreasing ACh release (similar to Lambert-Eaton).
2. It cleaves target synaptosome associated protein (SNAP) and N-ethylmaleimide-sensitive factor (NSF) attachment receptors (t-SNAREs) and vesicle SNAREs (v-SNAREs).
377
Symptoms of botulism toxin?
1. Blurred vision, unreactive pupils, diplopia, bulbar paralysis, and then respiratory suppression and quadriparesis in a descending pattern that evolves over 2-4 days.
2. No sensory changes.
378
MOA and symptoms of black widow spider bite?
1. Depletes the presynaptic ACh stores into the NMJ.
| 2. Cramps and spasms followed by weakness.
379
Pathophysiology of phenylketonuria?
1. Deficiency of phenylalanine hydroxylase.
| 2. Phenylalanine accumulates and causing defective myelination.
380
Genetics of PKU?
1. Autosomal recessive on chromosome 12.
381
Pathophysiology of homocystinuria?
1. Defect in methionine metabolism.
| 2. Increased homocysteine in the blood, urine and CSF.
382
Genetics of homocystinuria?
1. Autosomal recessive with a deficiency of cystathionine beta-synthase on chromosome 21.
383
Presentation of homocystinuria?
1. Physically similar to Marfan's (tall and thin), but with mental retardation and increased incidence of stroke, lens dislocation, and arachnodactyly.
384
Pathophysiology of maple syrup urine disease?
1. Decreased branch-chain amino acid catabolism caused by a deficiency of branched-chain alpha-keto acid dehydrogenase.
385
Pathophysiology of Hartnup disease?
1. Defect in amino acid transport in the proximal tubule of the nephron with inability to reabsorb neutral amino acids.
386
Presentation of Hartnup disease?
1. Niacin deficiency with pellagra like symptoms.
387
Pathophysiology of Niemann-Pick disease?
1. Deficiency in sphingomyelinase with accumulation of sphinomyelin and cholesterol.
388
Genetics of Niemann-Pick disease?
1. Autosomal recessive with chromosomal abnormalities on 11 and 18.
389
Presentation of Niemann-Pick disease?
1. Death within 2 years.
2. Cherry red spot (50%).
3. Supranuclear paresis of vertical gaze.
4. Pyschomotor retardation.
5. Hepatosplenomegaly.
390
Histological characteristics of Niemann-Pick disease?
1. Niemann-Pick cells or "foam cells" are large vacuolated histiocytes and lymphocytes.
391
Pathophysiology of Gaucher disease?
1. Deficiency of glucocerebrosidase with accumulation of glucocerebrosides.
392
Histological characteristics of Gaucher disease?
1. Gaucher cells have wrinkled tissue paper appearance from stored glucocerebrosidase.
393
Pathophysiology of Fabry disease?
1. Deficiency of alpha-galactosidase with accumulation of ceramides.
394
Genetics of Fabry disease?
1. X-linked recessive with onset in adolescence.
395
Presentation of Fabry disease?
1. Painful dysesthesias.
2. Hypertension.
3. Renal failure.
4. CHF.
5. Death by MI or stroke usually in the 6th decade.
396
Pathophysiology of Tay-Sachs disease?
1. Deficiency of hexosaminidase A with accumulation of GM2 gangliosides.
397
Presentation of Tay-Sachs disease?
1. Cherry red spots with macrocephaly without visceromegaly.
2. Hypotonia.
3. Seizures.
398
Pathophysiology of Sandhoff disease?
1. Deficiency of hexosaminidase A and B with accumulation of GM2 gangliosides.
399
Presentation of Sandhoff disease?
1. Similar clinical picture to Tay-Sachs disease, but has visceral storage in the liver, spleen, kidney, and heart.
400
Pathophysiology of GM1 gangliosidosis?
1. Deficiency of acid beta-galactosidase with accumulation of GM1 gangliosides.
401
Presentation of GM1 gangliosidosis?
1. Both CNS and visceral involvement with dysmorphic face, cherry red macula, hepatosplenomegaly, bone abnormalities, and contractures.
402
Pathophysiology of Hurler disease?
1. Deficiency of alpha-l-iduronidase with accumulation of mucopolysaccharides.
2. Urine contains heparin and dermatan sulfate.
403
Presentation of Hurler disease?
1. Gargoyle face, mental retardation, dwarfism, corneal opacities, conduction deafness, hepatosplenomegaly, cardiac dysfunction, skeletal abnormalities, and thick meninges that may cause spinal cord compression.
404
Histological characteristics of Hurler disease?
1. Zebra bodies.
405
What is Scheie syndrome?
1. Milder, rare form of Hurler disease with autosomal recessive inheritance.
2. There is no MR or neuronal storage.
3. May produce spinal cord compression from thickened dura, corneal opacities, and carpal tunnel syndrome.
406
Pathophysiology of Hunter syndrome?
1. Deficiency of iduronate sulfatase.
| 2. Urine contains heparin and dermatan sulfate.
407
Genetics of Hunter syndrome?
1. X-linked recessive.
408
Presentation of Hunter syndrome?
1. Similar to Hurler disease but milder, with no MR, less corneal clouding, and slower progression.
2. Characteristic skin pebbling and peripheral nerve entrapment.
409
Pathophysiology of Sanfilippo syndrome?
1. Deficiencies of heparin sulfate pathways.
| 2. Urine contains heparin sulfate.
410
Presentation of Sanfilippo syndrome?
1. MR, ataxia, dysostosis multiplex, and seizures but less corneal clouding and dwarfism.
411
Pathophysiology of Morquio syndrome?
1. Deficiency of galactose 6-sulfatase and beta-galactosidase.
2. Urine contains keratin sulfate.
412
Presentation of Morquio syndrome?
1. Severe skeletal abnormalities with ligamentous laxities, odontoid hypoplasia, and thick cervical dura with cervical myelopathy, dwarfism, and osteoporosis.
413
Pathophysiology of Maroteau-Lamy disease?
1. Deficiency of sulfatase B.
| 2. Urine contains dermatan sulfate.
414
Presentation of Maroteau-Lamy disease?
1. No MR but there may be carpal tunnel syndrome and valvular heart disease.
415
Pathophysiology of Sly syndrome?
1. Deficiency of beta-glucuronidase.
| 2. Urine contains dermatan sulfate, heparan sulfate and chondroitin sulfate.
416
Presentation of Sly syndrome?
1. Moderate MR, corneal clouding, hydrocephalus, hepatosplenomegaly, and bony changes.
417
Pathophysiology of Krabbe disease?
1. Deficiency of galactocerebrosidase beta-galactosidase on chromosome 14 with accumulation of galactocerebroside from myelin sheaths in lysosomes.
418
Presentation of Krabbe disease?
1. Pyschomotor delay.
2. Microcephaly.
3. Death by 2 years.
419
Most common leukodystrophy?
1. Metachromatic leukodystrophy.
420
Pathophysiology of metachromatic leukodystrophy?
1. Deficiency of arylsulfatase A with accumulation of sulfatides in lysosomes.
421
Pathophysiology of Pelizaeus-Merzbacher disease?
1. Defective synthesis of proteolipid protein, a myelin protein, required for oligodendrocyte differentiation and survival.
2. Atrophic brain with demyelination that spares perivascular white matter.
422
Presentation of Pelizaeus-Merzbacher disease?
1. Abnormal eye movements, spasticity, ataxia and MR.
| 2. Only leukodystrophy with 100% incidence of nystagmus.
423
Pathophysiology of Canavan disease?
1. Caused by a deficiency of N-acetyl-aspartoacylase.
424
Presentation of Canavan disease?
1. Brain actually increases in size, psychomotor regression, blindness, spasticity.
425
Pathophysiology of Alexander disease?
1. Defect in the GFAP gene.
| 2. Hemispheric demyelination with macrocephaly and mitochondrial dysfunction.
426
Pathophysiology of Refsum disease?
1. Autosomal recessive disease caused by a mutation in the gene encoding phytanic acid alpha-hydroxylase.
427
Presentation of Refsum disease?
1. Motor and sensory loss, ataxia, blindness, cardiac abnormalities, and deafness.
428
Symptoms of Kearns-Sayre syndrome?
1. Pigmentary retinopathy, cardiac abnormalities with heart block or cardiomyopathy, and progressive ophthalmoplegia.
429
Symptoms of Leber hereditary optic neuropathy?
1. Progressive painless loss of central vision.
430
Pathophysiology of Menke kinky hair disease?
1. Defect in copper absorption in the GI tract.
431
Symptoms of Menke kinky hair disease?
1. Secondary hair growth is brittle, twisted and colorless.
| 2. Seizures and MR.
432
Pathophysiology of Leigh disease?
1. Mitochondrial dysfunction by multiple metabolic defects.
433
What is Lowe syndrome?
1. An X-linked recessive disease causing bilateral cataracts, large eyes, nystagmus, psychomotor retardation, and death by renal failure.
434
What is Zellweger syndrome?
1. Autosomal recessive disease with decreased liver peroxisomes and accumulation of long chain fatty acids.
2. Presents with cortical dysgenesis and white matter degeneration with hepatorenal dysfunction.
435
What is Fahr disease?
1. Primary basal ganglia and cerebellar blood vessel calcification associated with renal disease or decreased parathyroid hormone.
436
What is Hallervorden-Spatz disease?
1. Occurs in late childhood with death in early adulthood.
| 2. Symptoms include extrapyramidal and corticospinal dysfunction with dementia.
437
What is Shy-Drager syndrome?
1. Multiple system atrophy with predominant autonomic dysfunction (orthostatic hypotension, urinary incontinence, impotence.
438
Pathophysiology of Friedreich ataxia?
1. Trinucleotide repeat that affects the frataxin gene on chromosome 9.
439
Pathophysiology of Werdnig-Hoffman disease?
1. Autosomal recessive inheritance on chromosome 5q.
| 2. Causes "floppy baby syndrome".
440
Pathophysiology of ALS?
1. Degeneration of motor neurons (including Betz cells) and the corticospinal tracts.
441
What are Bunina bodies?
1. Intracytoplasmic, anterior horn cells seen in ALS.
442
What diseases can cause strokes in children?
1. Fabry disease.
| 2. Homocystinuria.
443
What diseases can cause Parkinson symptoms in adolescents?
1. Wilson disease.
| 2. Hallervorden-Spatz disease.
444
What diseases can cause cerebellar degeneration?
1. Ethanol.
2. Dilantin.
3. Paraneoplastic syndromes.
4. Down syndorme.
5. Friedriech ataxia.
445
What is Devic disease?
1. A variant of acute MS in adults, primarily affects the optic nerves and spinal cord (acute necrotizing transverse myelitis).
446
What is Schilder disease?
1. Affects children.
| 2. Aggressive bilateral acute MS-type demyelination with hemispheric involvement that may also affect axons.
447
What cells in the brain are most vulnerable to ischemia?
1. Hippocampus, cortex (parietooccipital deep sulci), basal ganglia (caudate and putamen), and cerebellum (Purkinje cells).
448
What areas in the hippcampus are most susceptible to ischemia and which is most resistant?
1. CA1 (Sommer area) and CA3 (endplate) are most susceptible.
2. CA2 is the most resistant.
449
What is Benedikt syndrome?
1. Caused by a lesion in the tegmentum of the midbrain.
| 2. Causes CN III palsy with contralateral hemiplegia and cerebellar ataxia and tremor.
450
How does moyamoya present in children?
1. Ischemia and transient weakness.
451
How does moyamoya present in adults?
1. Hemorrhage.
452
What genetic mutation is responsible for CADASIL?
1. Mutation of the Notch 3 gene on chromosome 19.
453
How does CADASIL present?
1. Recurrent infarcts with subsequent dementia and leukoencephalopathy with U fiber sparing.
454
Presentation of Raeder syndrome?
1. Unilateral headache and face pain of the V1 and V2 distributions and Horner syndrome.
455
What is Terson syndrome?
1. Retinal hemorrhages associated with aSAH.
456
What is the hemorrhage risk for AVMs?
1. 2-4% per year.
457
If multiple AVMs exist, what conditions should you consider?
1. Wyburn-Mason and hereditary hemorrhagic telangiectasia.
458
Presentations of vein of Galen malformations?
1. Neonates: cyanotic heart disease.
2. Infant: hydrocephalus and seizures.
3. Children: SAH.
459
What is a type 1 vein of Galen malformation?
1. AV-fistula of the anterior and posterior choroidal arteries to the median venous sac (embryonal precursor of the vein of Galen).
460
What is a type 2 vein of Galen malformation?
1. Parenchymal AVM in the thalamus/midbrain with thalamoperforate feeders draining into the vein of Galen.
461
What genetic loci are associated with cavernous malformations?
1. CCM1.
2. CCM2.
3. PDCD10.
462
What is the most common vascular malformation?
1. Venous malformations.
463
What syndrome is associated with multiple venous malformations?
1. Blue rubber nevus syndrome.
464
What is sinus pericranii?
1. Large communication between intracranial and extracranial veins.
465
Imaging characteristics of DAI?
1. Hyperintense lesions on T2.
466
Describe subfalcine herniation.
1. Cingulate gyrus moves under the free edge of the falx and the ipsilateral foramen of Monro becomes trapped.
2. ACA may also be compressed.
467
Describe transtentorial herniation.
1. Uncus and parahippocampal gyrus is pushed over the tentorial edge.
2. Obliteration of the suprasellar cistern and inferomedial displacement of the anterior choroidal, PCOM, and PCA.
3. The PCA may become compressed causing occipital strokes.
4. The anterior choroidal artery and perforators may be compressed causing midbrain Duret hemorrhages and basal ganglia infarction.
468
Pathophysiology of fibrous dysplasia.
1. Expands and replaces normal bony medullary spaces with vascular fibrocellular tissue.
469
Definition of platybasia?
1. Flattened skull base with an increased angle of the clivus to the spine or clivus to the anterior fossa > 135 degrees.
470
What is caudal regression syndrome?
1. Consists of lumbosacral agenesis, imperforate anus, genital malformations, renal dysplasia, and sirenomelia (fused legs).
471
What is terminal myelocystocele?
1. Consists of posterior spina bifida or partial sacral agenesis with tethered cord and hydromyelia.
472
What is Foix-Alajouanine syndrome?
1. Subacute necrotizing myelitis, esepcially in the gray matter, usually with a type 1 AVM and caused by venous hypertension.
473
How does Foix-Alajouanine syndrome present?
1. Spastic and then flaccid paraplegia with an ascending sensory loss and loss of sphincter control.
474
What is Klippel-Trenaunay-Weber syndrome?
1. Spinal cord AVM with a cutaneous vascular nevus and an enlarged finger or upper limb (if cervical).
475
What is the pathophysiology of Charcot-Marie-Tooth disease?
1. Atrophy of the peroneal muscle and degeneration of anterior horn cells, posterior columns, DRG, axons and myelin.
476
How does Charcot-Marie-Tooth present?
1. Sensory ataxia and weakness without autonomic dysfunction.
2. Distal muscle atrophy occurs in the feet and then the hands (develop claw hand).
3. Patients develop pes cavus and hammertoe deformities.
477
How does Dejerine-Sottas disease present?
1. Slow, progressive development of claw feet and hands, symmetric weakness, wasting of distal limbs, foot pain, and paresthesias, without autonomic dysfunction.
478
Pathophysiology of Refsum disease?
1. Deficiency of phytanic acid oxidase with accumulation of phytanic acid.
479
How does Refsum disease present?
1. Distal symmetric sensorimotor loss in lower limbs, and is associated with retinitis pigmentosum, cardiomyopathy, and hearing loss.
480
How does posterior interosseus syndrome present?
1. Weakness of the radial-inervated forearm and hand muscles (supinator, extensor digitorum, extensor carpi ulnaris, and abductor pollicis longus).
2. No sensory loss.
3. Causes a finger drop without a wrist drop because of sparing of the extensor carpi radialis longus.
481
How does anterior interosseus syndrome present?
1. Pure weakness without sensory loss caused by compression of the anterior interosseus branch of the median nerve in the deep forearm.
2. Unable to form the "okay" sign and demonstrate the "pinched" sign.
482
How does tarsal tunnel syndrome present?
1. Compression of the tibial nerve with paresthesias of the sole of the foot without motor changes.
483
What is Ramsay-Hunt syndrome?
1. Herpes zoster infection of the geniculate ganglion with CN VII dysfunction, possibly CN VIII dysfunction, and vesicular lesions of the ear.
484
What are possible causes of bilateral CN VII nerve palsies?
1. Guillan-Barre and Lyme disease.
