Neurology Flashcards
Diseases associated with syringomyelia
trauma
Extrinsic compression
Arnold chiari malformation
Common location of syringomyelia
C8-t1
Cape like sensory loss
Due to involvement of anterior commisure in cord
Bilateral pain and temperature sensation lost
Fine touch and proprioception preserved because carried by dorsal columns which do not cross
What runs in lateral horn of spinal cord
Hypothalamospinal tract
Sympathetic outflow for face at T1
If affected because of syringomyelia causes horners syndrome
What are features of horners syndrome
Ptosis
Miosis
Anhidrosis
What is affected in poliomyelitis
Anterior horn cells
Lmn signs flaccid paralysis, weakness with atrophy, impaired reflexes with
Negative babinski—- downward going toes
DD is werdnig hoffman disease - floppy baby syndrome— AR INHERITED ANT MOTOR NEURON DEGENERATION DEATH IN FEW YEARS
What is floppy baby syndrome
Werdnig hoffman syndrome
It is an autosomal recessive inherited degeneration of anterior horn cell
Mimics polio symptoms
Death in few years after birth
What is amyolateral sclerosis
Degenerative upper and lower motor neuron disease ie of corticospinal tract
Anterior horn involvement —-LMN SIGNS
LATERAL CORTICOSPINAL TRACT INV—-UMN SIGNS
How can ALS and syringomyelia be differentiated
ALS is pure motor disorder no cape like sensory loss
What mutation can be seen in familial cases of ALS
Zine- copper superoxide dismutase
SOD Is important mechanism to manage oxygen free radical by converting it to hydrogen peroxide
What is freidreichs ataxia
Degenerative disorder of cerebellum and spinal cord tracts
Symptoms of freidrichs ataxia
Ataxia
Loss of vibration and proprioception
Muscle weakness in lower extremities
Loss of DTR
Genetic abnormality in freidrichs ataxia
AR
unstable GAA trinucleotide repeats in frataxin gene
Fra taxin—- iron toxin —- iron is toxic in mitochondria because abnormal iron metabolism in mitochondria generates free radicals
What age friedrichs ataxia presents
Childhood
Association of freidrichs ataxia
Hypertrophic cardiomyopathy
High yield
3 most common causes of
Meningitis in neonates
Grp B STREPTO
E COLI
L MONOCYTOGENES
Menignitis causes in children and teenages
Neisseria meningitidis
Meningitis in adults and elderly
Strep pneumo
Meningitis in. Non vaccinated infants
H influenza
Most common viral cause of meningitis
Coxsackie
LP FINDINGS IN BACTERIAL MENINGITIS
Neutrophils with low glucose
Positive gram stain
Positive culture
LP IN VIRAL MENINGITIS
Lymphocytes with normal CSF glucose
LP IN FUNGAL MENINGITIS
Lymphocytes with low CSF GLUCOSE
Causes of global cerebral ischemia
Low perfusion
Acute reduction in blood flow— SHOCK
chronic hypoxia— ANEMIA
repeated hypoglycemia—- INSULINOMA
Mild GCI resolves
Severe does cerebral necrosis and death or vegetative comma state
What are features of moderate or intermdiate form of GCI
Classic example is low perfusion hypotension
Infarcts in watershed areas
Damage to highly vulnerable areas of brain
What are the high vulnerable areas prone to damage in moderate global cerebral
Ischemia
Cortex neurons in layer 3 5 6 pyramidal neurons triangular appearence
Giving line of necrosis in 356
Ie cortical laminar necrosis
And pyramidal neurons of hippocampus ( long term memory)
Purkinje cells of cerebellum
Embolic stroke is
Haemorrhagic infarction
Lacunar stroke is due to
Hyaline arteriosclerosis
Cmnly in lenticulostriate vessels
Histology of ischemic stroke
Leads to liquefactive necrosis
1st sign— red neurons 12 hrs
2nd sign— cells come in - neutrophils and microglia for granulation tissue by 1 week
3rd sign— gliosis with fluid filled cystic spaces by 1 month
Common cause of intracranial haemorrhagd
Hypertension causes rupture of charcot bouchards microaneurysms
In basal ganglia
Other site— cerebellum
LP XANTHOCHROMIA
Yellow discolouration of csf due to SUBARACHNOID HAEMORRHAGE
Mst common cause of SAH
Berry aneurysms located in anterior circle of willis mostly near branch points of Acom
Diseases in which berry aneurysms are found
Marfans
AD PKD
Which vessel wall layer is lacking in berry aneurysm
Remember it is at branch point and it is a true aneurysm
Media layer
Muscle
Vessel most likely bleeding in epidural hematoma
Middle meningeal artery
Usually due to fractures of temporal bone
Lucid interval and herniation
Bleeding source in subdural
Hematoma
Bridging veins. Between dura and arachnoid
What structures are compressed due to uncal herniation
Cn 3 eye will be down out dilated and shut
PCA
Paramedian artery running on brain stem - gives rise to duret haemorrhages
What is the problem with leukodystrophies
Inherited disorders of enzymes needed for production and maintenance of myelin
Leads to demyelination
Which is the most common leukodystrophy
Metachromatic leukodystrophy
Def aryl sulfatase A
Myelin cannot be degraded.. sulfatides accumulates in neuron lysosomes
What is krabbes disease
Inherited leukodystrophy which has galactocerebroside- beta galatosidase
Galactocerebroside accumulates in macrophages
What is the biochemical problem
In adrenoleukodystrophh
Impaired addition of co enzyme A to VLCFA
Accumulates in adrenal gl and white matter
Xlr
What genetic suspceptibility does multiple sclerosis have
HLA DR2
Destruction of oligodendrocyte is main event
Hence leads to myelin loss
Scanning speach is seen in?
Multiple sclerosis
What structure involvement in multiple sclerosis leads to internuclear ophthalmoplegia
MLF
MEDIAL LONGITUDINAL FASCICULUS
What is internuclear ophthalmoplegia?
Both eyes do not turn together while looking at one direction
LP diagnosis of multiple sclerosis
Increased lymphocytes
Increased immunoglobulins
IgG oligoclonal bands
Presence of myelin basic protein
Locked in syndrome is seen in ?
Pontine lesions
Esp central pontine demyelination
All tracts in brainstem esp pons paralysed
Only cn 3 which is above pons is functioning
That is patient can move only eye and nothing else
Hence he gets locked in in his own body
MICTURITION CENTRE IN BRAIN IS LOCATED IN
MEDIAL FRONTAL LOBE - CINGULATE GYRUS
MANIFESTATIONS OF BILATERAL ACA OCCULUSION
BILATERAL SOMATOSENSORY AND MOTOR LOWER LIMB WEAKNESS
ABULIA (inability to take decisions)
SIGNIFICANT BEHAVIOURAL MALFUNCTION
MICTURITION CENTRE– URINARY INCONTINENCE
WHAT IS ANOSOGNOSIA
INABILITY TO IDENTIFY AND PERCEIVE HIS OR HER ILLNESS – FRONTAL LOBE INFARCTS MCA OCCLUSION
BROACAs aphasia
damage to dominant frontal lobe
damage to non dominant parietal lobe can lead to
hemineglect – loss of spatial sensation of opp half of body
MCA infarct leads to what type of blindness
cortex of temporal and parietal lobe affected – hence optic radiations are affected- ie contralateral homonymous hemianopia
conjugate deviation towards the side of stroke
MCA infarct
primary pathophysiology of lacunar infarcts
lipohyalinosis and microatheroma
what is lipohyalinosis
cause of lacunar infarcts – it is leakage of plasma proteins into vessel wall due to damaged endothelium.
leads to hyaline thickeneing
collageneous sclerosis
accumulation of foamy macrophages in wall.
features of thalamic stroke
complete (both anterior and dorsal column) sensory loss
gait disturbance due to loss of ataxia.
depending on thalamic nucleus involved – further symptoms arise.
all sensory information relays in thalamus except
olfaction
features of acute HIV
fever rash lymphadenopathy and painful oral tongue ulcers
motor supply of tongue is
hypoglossal nerve with exception of anterior tonsillar pillar – ie palatoglossus muscle supplied by vagus nerve.
general sensation of tongue
V3 division of trigeminal nerve in anterior 2/3rd
Glossopharyngeal in posterior 1/3rd
vagus nerve in the posterior most tongue – root area
gustatory sensation is carried by
chorda tympani branch of facial nerve in anterior 2/3rd of tongue
for rest it is same as general sensation
ie posterior 1/3rd taste is carried by 9th
posterior most root, pharynx and upper esophagus taste is carried by 10th vagus
contents of Superior orbital fissure
CN 3 -loss of adduction
NASOCILIARY BRANCH OF FACIAL NERVE - LOSS OF CORNEAL REFLEX
CN 4 AND 6 (LR 6 SO4)
SOV– Superior ophthalmic vein
the only two contents of optic canal
optic nerve and ophthalmic artery
contents of inferior orbital fissure – remember it has things which need to go to face
inferior orbital nerve and zygomatic nerve branches of V2 division of trigeminal nerve.
infraorbital vessels
ganglionic branches from pterygopalatine ganglion to V2 div
inferior ophthalmic vein
when a patient tells a story with memory gaps and fills those gaps with his own story which he believes to be true– this is known as ?
CONFABULATION due to thiamine deficiency inhibits new memory and learning also -- hence there is confabulation with anterograde amnesia usually permanent despite treatment part of korsakoff syndrome
korsakoff syndrome is damage to ?
anterior and dorsomedial thalamic nuclei
structures affected in thiamine deficiency
paraventricular structures like mamillary bodies, anterior and dorsomedial thalamic nuclei
CN 3, 6 and vestibular nuclei – horizontal gase palsy and bilateral abducens palsy
cerebellar cortex – gait ataxia
mental status changes - disorientation, apathy, confabulation and anterograde memory loss
What are the hall marks of korsakoffs syndrome
permanent memory loss and confabulation
what is cerebral amyloid angiopathy
deposition of b amyloid in small and medium size cerebral vessel wall making it weak and prone to rupture.
It is seen as recurrent lobar haemorrhages in elderly
most common cause of recurrent cerebral cortical haemorrhages in elderly
cerebral amyloid angiopathy
Cerebral amyloid angiopathy is not associated with systemic amyloidosis. It has the same amyloid as in Alzimers diesae
true
Vitamin E deficiency is extremely rare. Seen only in patients with ?
fat malabsorption - pancreatic insufficiency or cystic fibrosis
and
abetalipoproteinemia
DD of vitamin E deficiency induced neuro symptoms
Vitamin B12 def –SACD of spinal cord due to dorsal column involvement
Fredrichs ataxia
components of vitamin E def
hemolysis and neuro free radical damage
involvement of dorsal column - loss of vibration and proprioception
ATAXIA due to spinocerebellar tract involvement
Loss of DTR due to peripheral nerve degeneration eg sural nerve biopsy shows nonmyelination
associations of berry aneurysm
AD PKD MARFANS AND EHLERS DANLOS SYNDROME FMD MOYA MOYA DZ COARCTATION OF AORTA
WHAT IS THE MEANING OF CROSSED SIGNS
IPSILATERAL CRANIAL NERVE PALSIES WITH CONTRALATERAL HEMIPARESIS
SEEN IN BRAINSTEM LESIONS
WHAT IS VERNET JUGULAR FORAMEN SYNDROME
CRANIAL NERVE 9 10 11 PALSY
DYSPHAGIA HOARSENESS
LOSS OF GAG REFLEX
SHIFT OF UVULA TO NORMAL SIDE
WHAT IS BABINSKI SIGN
IT IS KNOWN AS PLANTAR REFLEX IE ON STROKING LATERAL SOLE MARGIN TILL BALL THE TOE GOES IN PLANTAR FLEXION… THIS IS NORMAL PHENOMENON.
IF NOT - UMN PALSY
WHAT IS ABNORMAL BABINSKI SIGN
TOE IN EXTENSION WITH OR WITHOUT FANNING OF LITTLE FINGERS
CHILDREN UNDER 12 YEARS WILL HAVE POSITIVE BABINSKI BECAUSE
OF INCOMPLETE MYELINATION OF CORTICOSPINAL TRACTS
WHAT IS PRONATOR DRIFT
PRONATION BECOMES MORE POWERFUL THAN SUPINATION OF FOREARM IN UMN PALSY
SIGNS OF UMN PALSY
HYPERREFLEXIA – -BRISK DTR
SPASTICITY
CLASP KNIFE RIGIDITY ON SUDDEN RELEASE OF PASSIVE FLEXION
INCREASED MUSCLE TONE
PRONATOR DRIFT
PYRAMIDAL WEAKNESS (LL FLEXORS AND UL EXTENSORS ARE MORE WEAK)
WHAT IS PYRAMIDAL WEAKNESS
LOWER LIMB FLEXORS AND UPPER LIMB EXTENSORS HAVE MORE WEAKNESS IN UPPER MOTOR NEURON PALSY
SIGNS OF LMN PALSY
MUSCLE WEAKNESS WITH HYPOTONIA LOSS OF DTR MUSCLE ATROPHY FASCICULATIONS OF SMALL GRP OF FIBRES BABINSKI WOULD BE NORMAL OR NO RESPONSE
during passive limb movement, if the movement is interrupted due to rhythmic contractions of muscle fibres which gets rigid is known as
cog wheel rigidity — seen in extrapyramidal tract signs which functions normally to modulate a motor action
what is cogwheel rigidity
increased muscle rigidity due to rhythmic muscle contraction during a passive movement. —sign of extrapyramidal tract lesion- parkinsons
muscles supplied by superior gluteal nerve
gluteus medius minimus
tensor fascia latae
difficulty in rising from seated position and climbing stairs
extension and external rotation of hip is not happening
gluteus maximus paralysed
inferior gluteal nerve palsy
impaired thigh adduction and medial thigh sensory loss
obturator nerve injury
location of red nucleus and its parts
ventral midbrain
divided into magnocellular and more important larger lower parvocellular
decorticate rigidity
flexion of upper arms to the core of body – flexor posturing is decorticate
indicates intact red nucleus (leading to disinhibition of nucleus and more active rubrospinal tract ie lesion is above red nucleus)
what is hypertrophic olivary degeneration
seen in direct damage to red nucleus
olives degenerated by shows hypertrophy
muscles like diaphragm, laryngeal muscles, soft palate and pharyngeal muscles shows rhythmic jerking motions
leads to palatal myoclonus and dysphagia
pathophysiology of decorticate rigidity
lesion is above red nucleus - red nucleus is intact.
downward to red nucleus has UMN TYPE changes — hypertonic rigidity – flexors of upper limb get rigid
CAFE AU LAIT SPOTS
LISCH NODULES ARE SEEN IN
NF1
CHROMOSOME FOR NF
17 FOR 1 —NEUROFIBROMIN
22 FOR 2 —MERLIN PROTEIN
PALISADES (natural cell and nuclear alignment stacking) ARE SEEN IN
SCHWANNOMA
PSEUDOPALISADES (nuclear or cell alignment around an area of necrosis )ARE SEEN IN
GBM
reticulin deposits and chronic inflammatory infiltrates are seen in which brain tumour
pleomorphic xanthoastrocytoma— mri cyst with solid enhancing nodule- peripherally location near leptomeninges and hence shows dural tail
ependymal cells palisading around blood vessel and hence are called perivascular pseudorossettes
ependymoma
A beta amyloid is a broken down product of —- accumulated in alzeimers disease
App receptor
APP receptor if broken down by beta secretase gives beta amyloid protein
What is definition of dementia
Cognitive + memory loss
Without any loss of consciousness
Increased ApoE4 allele is associated with
Sporadic form of ALzeimers d
ApoE2 form is associated with
Protective apo E2
Hence if reduced leads to ALZ DZ
Associations of early onset alziehmers
Presenilin 1
Downs syndrome because trisomy 21
And App protein which breakdown leads to ALZ DZ is on chromosome 21 hence downs patients have too many APP proteins leading to early onset
What is tau
Tau is a microtubule associated protein which is needed to organise microtubules
In cytoplasm
Round aggregates of tau proteins in cortical neurons
Picks disease
Which is degenrstive dementia with behaviour and language symptoms due to frontal and temporal involvement
MPTP neurotoxin
Methyl phenyl tetrapyridine
Parkinsons disease
Features of parkinsons disease
Trap
TRAP Tremors- resting Rigidity- cogwheel Akinesia and bradykinesia— expressionless face Posture—instability and shuffling gait
Lewy body is composed of
Alpha synuclein
In parkinsons disease histology shows
Loss of dopamingergic black neurons in substantia nigra pars compacta
Lewy bodies—round eosinophilic granular body
In parkinsons disease dementia is a early or late feature?
Late feature
If early alternate diagnosis of lewy body dementia suggested
which cranial nerve exits brain stem in post olivary sulcus of medulla
9th and 10th CN
what is chorea
jerky fidgety involuntary movements
what is the genetic defect in huntingtons chorea
AD CAG trinucleotide repeats causing gain of function mutation leading to huntingtin protein accumulation in neural cells
what organ is affected in huntingtons disease
caudate nucleus (striatum) accumulation of huntingtin protein in caudate leads to loss and atrophy of inhibitory GABA neurons of caudate.
what happens when GABA neurons of caudate are lost
in huntingtons dz– inhibitory GABA in caudate is lost. It would normally regulate motor and behaviour from cortex. Hence pts have behavioural abnormality and movement disorder
what should u suspect in advanced dementia — severe memory loss, facial agnosia, bradykinesia, incontinence and near total absence of voluntary movements
huntingtons disease
where is acetylcholine produced in brain
largest concentration is seen in amygdala– in nucleus basalis of meynert
reduced concentration of NE and serotonin causes
in brain it causes depression. Treated with SSRI and SNRI
anterior spinal artery occlusion symptoms would be ?
bilateral lower limb weakness with hyporeflexia LMN type
loss of pain and temperature becuase of spinothalamic tract involvement
what is wallenberg syn?
lateral medullary PICA syndrome. Infarct in lateral medulla and inferior cerebellar peduncle
features of lateral medullary pICA syndrome / wallenberg syn
lateral medulla and inferior cerebellar peduncle infarcted.
hence dysphagia, hiccups, hoarseness and vestibulocochlear sym… ataxia dizziness and nystagmus
SIADH because vagus mediated sensing of non osmotic stimuli from carotid sinus is not mediated and disinhibition of ADH occurs
cause of hyperacusis
stapedius muscle paralysis causes stapes to vibrate violently. facial nerve palsy.
treatment of hyperacusis
white noise – therapy with white noise
what are diagnostic features of neuroblastoma
elevated catecholamine metabolites.
c-myc amplification
small round blue cells WITH HOMER WRIGHT ROSETTES on histo– remember it is a type of round cell tumour
what movement disorder should prompt the diagnosis of neuroblastoma
non rhythmic conjugate eye movements
involuntary jerking movement of trunk and limbs
that is OPSOCLONUS MYOCLONUS SYN
CNS LYMPHOMA HAS WHICH POSITIVE MARKERS
CD20 AND CD 79a
which CNS tumour is associated with EBV genome
primary CNS lymphoma.
