soal gambar 2 Flashcards
QUESTIONS 73-80
Directions: Match each of the spinal cord tracts with the appropriate clinical correlate (Figure 8.73-8.80), using each answer once, more than once, or not at all. Major ascending tracts are depicted on the left, while descending tracts are shown on the right.
Ascending Tracts Descending Tracts
FIGURE 8.73-80Q
73. Small peripheral myelinated fibers of this pathway
synapse in the substantia gelatinosa of the dorsal horn
74. These fibers pass through the superior cerebellar peduncle
75. This tract arises from Dieter’s nucleus
76. Conscious proprioception from the legs is mainly transmitted in this tract
77. Carries fibers from medial and inferior vestibular nuclei,tectospinal tract, and interstitial nucleus of Cajal
78. Fibers from this tract originate from layer V of the
cerebral cortex
79. Carries fibers that ascend to either the thalamus, periaqueductal gray, reticular formation, or superior colliculus
80. Uncrossed pyramidal fibers mainly supplying the axial musculature
73-1; 74-J; 75-F; 76-B; 77-G; 78-C; 79-1; 80-H. The major ascend¬ing tracts of the spinal cord (left) are the dorsal columns, spinothalamic tract, dorsal spinocerebellar tract, and ventral spinocerebellar tract. The dorsal columns convey tactile discrimination (Meissner corpuscles), vibration (pacinian corpuscle), joint position sense (muscle spindles and Golgi tendon organs), and conscious proprioception. First-order neurons give rise to axons that ascend in the fasciculus cuneatus (A, upper extremity fibers) and gracilis (B, lower extremity), which terminate in the gracile and cuneate nuclei of the medulla. Second-order neurons, known as arcuate fibers, cross to the contralateral side as the medial lemniscus and ascend to the ventral posterolateral (VPL) nucleus of the thalamus. Synaptic connections are then made in the thalamus with third-order neurons, which travel through the posterior limb of the internal capsule to reach the postcentral gyrus of the cerebral cortex.
Four groups of fibers have been distinguished in the anterolateral system (I) on the basis of their anatomic projections: spinothalamic, spinoreticular, spinomesen-cephalic, and spinotectal. First-order neurons of the lateral spinothalamic tract (pain and temperature sensation) pro¬ject axons via the dorsolateral tract of Lissauer to second-order neurons in the substantia gelatinosa of the dorsal horn. Second-order neurons then decussate in the ventral white commissure, ascend in the ventral half of the lateral funiculus, and synapse in the VPL nucleus of the thalamus. Third-order neurons from the thalamus are then relayed to the somatosensory cortex of the postcentral gyrus (areas 3, 1, and 2) through the posterior limb of the internal capsule. A number of collateral fibers from the spinothalamic tract are relayed to the reticular formation (spinoreticulothalamic tract), which transmits nociceptive fibers to the intralaminar nuclei of the thalamus. Additional fibers of the anterolateral system terminate in either the periaqueductal gray (spino-mesencephalic) or the deep layers of the superior colliculus (spinotectal). The periaqueductal gray sends descending projections to serotonergic neurons of the raphe nucleus of the pons and nucleus gigantocellularis (noradrenergic neurons) of the medulla. Both of these areas, in turn, send projections to the dorsal horn and inhibit postsynaptic responses to nociceptive input. The spinotectal pathway directs visual attention to areas of the body that experience intense somatosensory input. Other pathways, such as the dorsal spinocerebellar (K) and ventral spinocerebellar tracts (J), transmit unconscious proprioception from the lower limbs and inferior half of the body to the cerebellum, while the cuneocerebellar and rostrocerebellar tracts convey
- The finding depicted on the CT scan below (Figure 8.83Q) is most likely to occur after
FIGURE 8.83Q
A. Berry aneurysm rupture
B. Infection
C. Extradural carotid artery dissection
D. Trauma
E. Contrast administration
- D. This CT demonstrates a subarachnoid hemorrhage (SAH), which is most commonly seen after trauma. Although the blood pattern may vary, traumatic SAH often involves the convexities of the cerebral hemispheres, while aneurysmal subarachnoid hemorrhages generally have a preponderance of blood in the basal cisterns (Greenberg, p. 754).
QUESTIONS 85-86
85. Refer to Figure 8.85-8.860;. What is the most likely
diagnosis?
A. Pilocytic astrocytoma
B. Medulloblastoma
C. Subacute infarct
D. Lhermitte-Duclos disease
E. Ependymoma
- Which of the following best characterizes this abnormality?
A. These lesions typically have an abundance of Rosenthal fibers
B. Most often secondary to vertebral artery occlusion
C. Hypertrophy of granular-cell neurons and axonal
hypermyelination in the molecular layer
D. Evidence of Homer-Wright rosettes on histopathologic sectioning
E. Pseudorosettes on histopathologic sectioning
85-D; 86-C. This T2-weighted image shows the hyperintense and thickened folia in a characteristic laminated pattern that is most consistent with Lhermitte-Duclos disease. It is associated with hypertrophy of granular cell neurons and axonal hypermyelination in the molecular layer (Osborn DN, pp. 69-70).
- A 42-year-old female presents to the emergency
department with staring spells and the T2-weighted MR
image depicted below (Figure 8.87Q). What is the most likely
diagnosis?
FIGURE 8.87Q
A. Temporal lobe ganglioglioma
B. Dysembryoplastic neuroepithelial tumor
C. Epidermoid cyst
D. Aneurysm
E. Neurocysticercosis
- The lesion depicted on the photomicrograph below (Figure8.97Q) may be associated with all of the following EXCEPT?
FIGURE 8.97Q
A. Autosomal dominant inheritance
B. Renal cell carcinoma
C. Pancreatic cysts
D. Overproduction of erythropoietin
E. Tumor suppressor gene that maps to chromosome 9p25
- E. Note the numerous capillaries and cells with a vacuo-lated appearance in this photomicrograph depicting a hemangioblastoma. This tumor is associated with VHL in about 25% of cases, is carried in an autosomal dominant fashion (chromosome 3p25), and is associated with retinal angioma, renal cell carcinoma, renal and pancreatic cysts, pheochromocytoma, or epididymal papillary cystadenoma. This tumor may cause polycythemia in about 10% of cases due to inappropriate production of erythropoietin (Ellison,
pp. 736-738).
- This axial CT scan (Figure 8.201OJ demonstrates
FIGURE 8.201Q
A. Arachnoiditis
B. Hypertrophy of the ligamentum flavum
C. Synovial cyst
D. Laminar fracture
E. Hemangioma
- A. Note the multiple prominent irregularities and loculations located circumferentially around the margins of the dura on this GT myelogram, which is most consistent with arachnoiditis (Ramsey, pp. 739-741).
- The EEG below (Figure 8.203Q.) is most consistent
with?
FIGURE 8.203Q
A. Alcohol intoxication
B. Left frontal lobe mass
C. A lethal closed head injury
D. Hepatic encephalopathy
E. Delta rhythm
- What abnormality is depicted on the EGG below (Figure8.204Q)?
FIGURE 8.204Q
A. Torsades de pointes
B. Hyperkalemia
C. Digoxin toxicity
D. First-degree heart block
E. Multifocal atrial tachycardia
- B. The most potentially serious complication of hyper-kalemia is slowing of electrical heart conduction. The ECG begins to change when the serum K* reaches approximately 6.0 mEq/L and is always abnormal when it is > 8.0 mEq/L. The earliest ECG abnormality is a tall, tapering T wave that is most evident in the precordial leads V2 and V3. As K* levels increase further, the P-wave amplitude decreases and the PR interval lengthens. The P waves may eventually disappear and the QRS complex widen. The final event is ventricular asystole (Marino, pp. 65 4-6 5 5).
QUESTIONS 205-209
Directions: Match the visual field cut (Figure 8.205-8.209OJ with the most likely lesion site.
FIGURE 8.205-209Q
205. Temporal lobe
206. Lateral posterior choroidal artery
207. Anterior chiasm
208. Anterior calcarine cortex
209. Anterior choroidal artery
205-E; 206-D; 207-A; 208-C; 209-B. Occlusion of the anterior choroidal artery causes a homonymous defect in the upper and lower quadrants, with sparing of the horizontal sector (quadruple sectoranopia, B), which is usually characteristic of a lateral geniculate body infarct that is supplied by the anterior choroidal artery. The central portion of the lateral geniculate body receives blood flow primarily from the lat¬eral posterior choroidal artery. Interruption of this vessel causes a horizontal homonymous sector defect (wedge-shaped, D). Superior homonymous quadrantic defects (“pie-in the sky,” E) may result from a lesion along Meyer’s loop (after temporal lobectomy) or along the inferior bank of the calcarine fissure. The anterior chiasm or junctional syndrome results in a unilateral optic nerve defect of one eye and a superior temporal defect in the other eye (A) due to the loop made by the inferonasal retina of the other eye (Willebrand’s knee). Lesions located in the most anterior portion of the calcarine cortex cause a crescent-shaped defect restricted to the temporal field of the contralateral eye (monocular temporal crescent, C). This is the only retrochi-asmatic lesion that may result in a strictly unilateral visual field defect (Brazis, pp. 132-140).
QUESTIONS 212-213
212. Refer to Figure 8.212-8.213Q. What is the diagnosis?
A. Alobar holoprosencephaly
B. Lobar holoprosencephaly
C. Hydranencephaly
D. Severe hydrocephalus
E. Anencephaly
- What is the most likely etiology of this finding?
A. Obstructive hydrocephalus
B. Failure of disjunction
C. Disorder of cellular migration
D. Bilateral in utero disruption of the anterior circulation
E. Failure of neural tube closure
212-C; 213-C. Hydranencephaly describes a brain replaced by CSF rather than compressed by expansion of the ventricles, as in severe hydrocephalus. Moreover, with severe hydro-cephalus, there is usually a thin mantle of brain, which is absent in hydranencephaly. The absence of a cortical mantle with hydranencephaly is most often associated with angio-graphic evidence of supraclinoid occlusion of the carotid arteries, which strongly suggests a vascular pathogenesis. The posterior fossa and thalami are often preserved due to preserved posterior circulation. The cranium of afflicted children usually fails to grow and remains small. The incidence is estimated to be 1 in 6000, and affected infants rarely live longer than a year (Albright, pp. 1 55-1 56).
- What is depicted by the photomicrograph below (Figure 8.215QJ?
FIGURE 8.215Q
A. Gemistocytic astrocytoma
B. Hemangioblastoma
C. Chordoma
D. Clear cell meningioma
E. Desmoplastic medulloblastoma
- A. Note the large, glassy eosinophilic cell bodies with an angular shape on this photomicrograph, which depicts a gemistocytic astrocytoma (Ellison, p. 627; WHO, p. 25).
- A 35-year-old male with the photomicrograph depicted below (Figure 8.218Q.) presents with fever, chills, and a seizure. What is the diagnosis?
FIGURE 8.218Q
A. Creutzfeldt-Jakob disease
B. Herpes encephalitis
C. Malaria
D. Ganglioglioma
E. Lymphoma
- C. Note the occlusion of the blood vessel, which is due to the presence of many ghost-like red blood cells that contain parasites on this H& E section depicting malaria. Patients with this disease can present with seizures, headache, somnolence, confusion, photophobia, and almost any focal neurologic deficit. Without urgent treatment, these patients usually progress to coma and brain death (Ellison,
pp. 653-656).
- The lesion depicted below (Figure 8.219QJ is most often associated with what other abnormality?
FIGURE 8.219Q
A. Castleman’s syndrome
B. Tuberous sclerosis
C. Temporal lobe epilepsy
D. Cafe au lait spots
E. Cobblestone skin pattern
- B. This photomicrograph depicts a subependymal giant cell astrocytoma. This lesion is usually located adjacent to the foramen of Monro and is associated with tuberous sclerosis (dominant mutation in TSC 1 on 9p or TSC 2 on 16p). It usually resembles gemistocytic astrocytoma, but is not infiltrative. Note the abundant cytoplasm, abundant perivascular fibrillar zone, and prominent nucleolus in this section. The nuclei are eccentric, which distinguishes this from gemistocytic astrocytoma (Ellison, pp. 637-639).
- The EEG below (Figure S.225Q.) is most consistent with what diagnosis?
FIGURE 8.225Q
A. Right frontal tumor
B. Left occipital tumor
C. Uremia
D. Sleep
E. Large hemispheric insult
- A. The seizure spikes are over a fairly wide area of the right parasagittal region (maximal F4, C4) consistent with a right frontal onset corresponding with a right parasagittal meningioma. In order to localize seizure foci, it is imperative for clinicians to memorize standard electrode placement and designations. Note that by convention, electrodes designated with odd numbers are on the left, while with even numbers on the right. The standard electrode designations are as follows: Fpl/Fp2 = frontopolar or prefrontal; F3/F4 = mid-frontal; C3/C4 = central (roughly over central sulcus); P3/P4 = parietal; 01/02 = occipital; F7/F8 = inferior frontal (some-times called anterior frontal); T3/T4 = midtemporal (records activity over anterior and midtemporal activity, important for temporal lobe epilepsy); T5/T6 = posterior temporal; Fz, Cz, Pz = midline electrodes in frontal and parietal regions (record mesial surfaces of hemispheres); A1/A2 = ear refer¬ence electrodes (while used for references also record midtemporal activity); T1/T2 = so-called true anterior tem¬poral electrodes; Spl/Sp2 - sphenoidal electrodes (record activity from inferomesial surface of the temporal lobes) (Rowan, pp. 4-7
QUESTIONS 226-231
Directions: The following is a schematic diagram through the pallidofugal fiber system in a coronal plane. Match the fibers (numbered items) with the appropriate letterhead (Figure 8.226-8.231Q), using each answer either once, more than once, or not at all.
FIGURE 8.226-231Q
226. Ansa lenticularis
227. Thalamostriate fibers
228. Optic tract
229. Subthalamic fasciculus
230. Thalamic fasciculus (HI)
231. Lenticular fasciculus (H2)
226-D; 227-E; 228-F; 229-C; 230-A; 231-B. Fibers of the ansa lenticularis (D) leave the outer part of the medial globus pallidus, pass around the internal capsule, and enter the pre-rubral field (field H of Forel, not labeled) prior to merging with the lenticular fasciculus (H2). Fibers of the lenticular fasciculus originate from the inner part of the medial globus pallidus, traverse the posterior limb of the anterior capsule, and pass medially, dorsal to the subthalamic nucleus, to also enter the pre rubral field. The ansa lenticularis and lenticular fasciculus then travel together dorsal to the zona incerta as components of the thalamic fasciculus (A). The subthalamic fasciculus (G) is comprised of pallidosubthalamic fibers originating from the lateral or external pallidal segment and subthalamopallidal fibers that terminate in the medullary lamina of both pallidal segments. Both components of the subthalamic fasciculus cross the internal capsule. Thalamo-striate fibers from the centromedian nucleus project to the putamen (E) (Carpenter, pp. 337-345).
- A 31-year-old immunocompromised male with a history of intravenous drug abuse presents with back pain. His sagittal postcontrasted Tl-weighted MRI is depicted below (Figure 8.232Q). What is the most likely diagnosis?
FIGURE 8.232Q
A. Leukemia
B. Lymphoma
C. Epidural abscess
D. Epidural lipomatosis
E. Hemangioblastoma
- C. Note the prominent ring enhancement of this spinal epidural abscess, with compression of the adjacent spinal cord. The most likely causative organism in a patient with a history of intravenous drug abuse is Staph, aureus (Ramsey, pp. 498-502).
QUESTIONS 241-242
241. Refer to Figure 8.241-8.2420:. What is the most likely diagnosis of this patient?
FIGURE 8.241-242Q
A. Sphenoid wing meningioma
B. Chondrosarcoma
C. Fibrous dysplasia
D. Esthenioblastoma
E. Osteochondroma
242. Malignant degeneration of this lesion is most likely to produce what type of neoplasm?
A. Osteochondroma
B. Osteoblastoma
C. Chloroma
D. Osteosarcoma
E. Neuroblastoma
241-C; 242-D. Note the expansion of bone (sphenoid) and “ground glass appearance” on this noncontrasted CT scan in a patient with fibrous dysplasia. Malignant degeneration, usually to osteosarcoma, has been reported to occur in approximately 0.5% of patients with fibrous dysplasia (Albright, pp. 4 56-4 57).
- An 18-year-old male presents to the emergency department with morning headaches associated with nausea andright arm numbness; his CT scan showed a low-density areain the left parietal region. The angiogram is depicted below(Figure 8.244Q). What is the most likely diagnosis?
FIGURE 8.244Q
A. Atherosclerosis
B. Malignant brain tumor
C. Fibromuscular dysplasia
D. Moyamoya disease
E. Embolic infarct
- D. Note the paucity of blood flow in the distal internal carotid and cerebral artery vasculature and the presence of prominent collaterals that resemble a “puff of smoke” on this lateral angiogram, which depicts moyamoya (Albright, pp. 1053-1069).
