Peer Support – all of the Neuroanatomy... Kassia and Dave

A male aged 25 was admitted to hospital after a lorry vs pedestrian RTC. He was conscious and on initial examination you note a flaccid paralysis associated with the right hand and the right lower limb. Head CT was clear. What anatomical structure do you suspect has been damaged? What type of symptoms are these (LMN vs UMN)? Spinal cord injury from trauma LMN – flaccid paralysis, hyporeflexia, hypotonia, atrophy (due to spinal shock)

Descending tracts – motor Decussate in thalamus, so brain lesions contralateral, spinal and LMN lesions ipsilateral Exit out ventral horn Pyrimidal vs extrapyramidal; Corticospinal and rubrospinal = pyramidal (conscious and voluntary control) Signs = Babinski’s (from UMN), loss of abdo and cremasteric reflexes, loss of fine skilled movements Extra-pyramidal = everything else Signs = normal UMN ie bilateral spastic paralysis, hypertonia, hyperreflexia, no muscle atrophy cuneatus

The patient also has sensory loss. What different types of sensation (that you could examine separately) would you group together? Fine touch, pain and temperature (spinothalamic) – decussates 1-2 levels above entry level, so symptoms contralateral to UMN lesion 1-2 levels below Discriminative touch, vibration, proprioception (dorsal and spinocerebellar) – decussates in thalamus, so symptoms ipsilateral to spinal lesion

Several months later you check on the progress of the patient and note further changes in motor function including paralysis and severe atrophy of muscles in medial aspects of the right hand and arm. Furthermore, there is right lower limb paralysis along with hypertonia and hypereflexia. You also note clonus and an extensor plantar response (babinski sign) on stroking the sole of the right foot. However there appeared little muscle atrophy associated with the right leg compared to that observed in the hand. What type of symptoms are these? Do they suggest a specific descending tract has been affected? UMN – no, both pyramidal and extrapyramidal signs

Patient also has lost pain and temperature sensation on medial side of RUL and on LHS from 2 nd rib – foot, and vibration, discriminative touch and proprioception in Right upper and lower limbs. Where would you expect the damage to the spinal cord to be? 1) 2) 3) 4) Which vertebral level has been affected? C7 (C8/T1 nerve roots)

Keith, a 68 year old man, was found collapsed at home by his wife. Examination revealed paralysis of his right upper limb and face but not his lower limb. Keith now has trouble comprehending spoken and written language and producing coherent speech. What is the likely diagnosis? Stroke

Aneurysms can occur at the junction of vessels within the circle of Willis where there is inherent weakness. Anterior inferior cerebellar Posterior inferior cerebellar (PICA) Superior cerebellar Middle cerebral Anterior cerebral Posterior cerebral Basilar Vertebral Internal carotid Anterior communicating Posterior communicating Vertebrobasilar Arterial System Optic chiasm Pituitary stalk Anterior inferior cerebellar Posterior inferior cerebellar (PICA) Superior cerebellar Middle cerebral Anterior cerebral Posterior cerebral Basilar Vertebral Internal carotid Anterior communicating Posterior communicating

Blockage of which artery is most likely to explain Keith’s symptoms? Cerebral Artery Territories PCA ACA Striate Choroidal MCA Left middle cerebral artery

Understanding and interpretation of written and spoken language Motor planning involved in speech Wernicke’s (receptive) dysphasia Speak in long sentences that have no meaning, add unnecessary words, and/or create new "words" (neologisms) Broca’s (expressive) dysphasia Speak in short, meaningful phrases that are produced with great effort Dysphasia

A 35 year old man complains of the worst headache of his life before losing consciousness. CT scan findings are consistent with a subarachnoid haemorrhage. Which of the following is the most likely aetiology? a)Carotid artery occlusion b)Middle meningeal artery laceration c)Ruptured aneurysm in the circle of Willis d)Middle meningeal artery occulsion

A 64 year old man is diagnosed with a stroke. His main deficit is a partial loss of his visual field resulting from a lesion in the occipital lobe. Which of the following arteries is likely to be involved? a)Internal carotid b)External carotid c)Middle cerebral d)Posterior cerebral

Other stuff to revise Basal Ganglia anatomy and pathways Layers of the brain/meningitis Groupings of cranial nerves eg cavernous sinus, nuclei, bulbar vs pseudobulbar palsy Disc prolapse, cauda equina syndrome, sciatica, brown sequard, spinal shock

Brain + behaviour -> resources -> guides

62 yr old male patient comes into A+E with a arm laceration from a bike which he didn’t see. He complains of gradual progressive visual loss over the last 6 months, and when you do confrontation you discover he cannot see to his left. What is this called? Left homonymous hemianopia

Terminology; hemianopia, homonymous, bitemporal/binasal, side

How would you record this patients homonymous hemianopia in the notes? 1) 2) 3) 4)

Where would the lesion have to be to cause these symptoms? 1)On the left optic nerve 2)On the left optic radiation 3)On the right occipital lobe 4)On the optic chiasm

Tom, a 22 year old student, presents to his GP complaining of double vision. He has no known previous medical conditions or visual problems. Examination revealed ptosis, an unreactive dilated pupil and displacement “down and out” in his left eye. Direct and consensual pupillary reflexes of the right eye were intact. Which nerve palsy is demonstrated in this case? Occulomotor (CNIII)

Muscles of the eye SR – Superior rectus IR – Inferior rectus MR – Medial rectus LR – Lateral rectus SO – Superior oblique IO – Inferior oblique IR LR IO SO SR LPS

Cranial Nerves III, IV and IV Cranial Nerve FunctionDysfunction Occulomotor (CNIII) Superior rectus Inferior rectus Medial rectus Inferior oblique Levator palpebrae superioris (elevation of the upper eyelid) Sphincter pupillae (pupillary constriction) Ciliary body (accommodation reflex) Ptosis Unreactive dilated pupil Divergent squint (down and out) Horizontal and vertical diplopia Absent accommodation reflex Trochlea (CNIV) Superior obliqueDivergent squint (up and out) Vertical diplopia Abducens (CNVI) Lateral rectusInability to abduct the eye Convergent squint (resting adduction) Horizontal diplopia

Elevation Depression Abduction Lateral rectus Adduction Medial rectus Superior Rectus Inferior Rectus Superior Oblique Inferior Oblique Nose Superior Oblique Lateral rectusMedial rectus Superior Rectus Inferior Oblique Inferior Rectus Movement Test

How would you test the function of the superior oblique muscle in a physical examination? a)Check for accommodation reflex b)Look laterally c)Look in toward the nose and then down d)Look laterally and then down

During a physical examination, you ask the patient to look laterally with her right eye and then upward. You have just tested the function of which muscle? a)Left Superior rectus b)Right Superior rectus c)Right Inferior Oblique d)Right Superior oblique