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MH SAQ practice neurosurgery/eyes A 25 year old male was assaulted with a baseball bat. He had a witnessed LOC for 5 minutes and GCS was 10 when paramedics attended. On arrival to the ED, he had a generalised seizure following which he became agitated and combative with a GCS of 8. His left pupil is dilated and he has already vomited at scene and the ED. R L 1. Describe the 4 abnormalities on this CT (2 marks) midline shift acute left subdural haemorrhage acute right extradural haemorrhage left frontal intracerebral haemorrhage 2. List 9 important initial steps in this patient’s initial primary survey, including end points where appropriate (6 marks) secure the airway/ intubate C-spine immobilisation maintain normoxaemia PO2 100mmHg ventilate to maintain PCO2 35-40mmHg secure IV access, crystalloids to maintain MAP >65mmHg, SBP > 90mmHg inotropes noradrenaline once fluid deficit corrected to maintatin MAP>65 maintain normoglycaemia normothermia phenytoin loading dose to minimise early seizures/ secondary brain injury NB score 2 marks for each 3 steps named

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MH SAQ practice neurosurgery/eyes

A 25 year old male was assaulted with a baseball bat. He had a witnessed LOC for 5 minutes and GCS was 10 when paramedics attended. On arrival to the ED, he had a generalised seizure following which he became agitated and combative with a GCS of 8. His left pupil is dilated and he has already vomited at scene and the ED.

R L

1. Describe the 4 abnormalities on this CT (2 marks)

midline shift acute left subdural haemorrhage acute right extradural haemorrhage left frontal intracerebral haemorrhage

2. List 9 important initial steps in this patient’s initial primary survey, including end points where appropriate (6 marks)

secure the airway/ intubate C-spine immobilisation maintain normoxaemia PO2 100mmHg ventilate to maintain PCO2 35-40mmHg secure IV access, crystalloids to maintain MAP >65mmHg, SBP > 90mmHg inotropes noradrenaline once fluid deficit corrected to maintatin MAP>65 maintain normoglycaemia normothermia phenytoin loading dose to minimise early seizures/ secondary brain injury

NB score 2 marks for each 3 steps named

3. Describe the methods of reducing intracranial pressure in this patient and the rationale of each method (2 marks)

hyperventilation – temporary vasoconstriction at the expense of cerebral perfusion prior to theatre

mannitol – 0.25 1.0g/kg – osmotic gradient, can be detrimental with disrupted blood brain barrier or cardiovascular instability

hypertonic saline head elevation 30 degrees optimise cerebral venous drainage

NB need to describe 4 methods to score 2 marks

A 45 year-old female has long standing low back pain was discharged the preceding day by a JMO in your ED with a diagnosis of malingering. She now presents to the ED with a sudden and severe lower back pain radiating down the legs. In the department she was unable to control herself and was incontinent of urine.

1. What 6 features would suggest cauda equina syndrome? (3 marks)

sciatica variable motor and sensory loss both lower limbs urinary incontinence bowel dysfunction saddle anaesthesia bilaterally absent ankle reflexes

need to score 2 correct answers for each 1 mark

2. List the essential test to aid the assessment of a patient with suspected cauda equina syndrome (1 mark)

MRI

3. You investigate and find that the JMO did not examine the patient, wrote no notes and was heard by the ED RN to tell the patient that there is nothing wrong with them and they should not have come to the ED, again. You are the JMO’s supervisor. Outline your approach to this situation (4 marks)

Arrange to speak with the JMO privately Assess if any drugs, alcohol, mental health issues with the JMO and if concern

escalate to ED Director and or medical board Educate that not appropriate was of handling this situation Document record of conversation Inform JMO that patient may complain – should contact medical defence and write

contemporaneous notes Review departmental protocol for JMO supervision

4. Outline the immediate steps in the management of this patient (2 marks)

bedrest with pressure relieving mattress bladder scan/ urinary catheter analgesia neurosurgical review discectomy/ laminectomy

Q1. A 57 years old male presented to ED with a sudden onset red painful right eye. You suspect a diagnosis of acute glaucoma

1. What are the features of acute Glaucoma on examination? (4 marks)

Fixed semi dilated pupils Hazy cornea shallow anterior chamber increased intraocular pressure

2. How does glaucoma cause blindness? (1 mark)

High intraocular pressure causes direct optic nerve damage

3. List the 5 most relevant topical medications used in primary open angle glaucoma and explain why they are used: (5 marks)

Prostaglandin analogues (e.g. Latanoprost): increase aqueous outflow: first line Beta blockers e.g. Timolol; Reduces aqueous humour production by blocking Beta

receptor: first line Alpha2 agonists: e.g. apraclonidine; increase aqueous outflow and decrease

aqueous production: second line agent. Carbonic anhydrase inhibitors topical e.g. Brinzolamide, decrease aqueous

production ; second line agent cholinergics (miotics) e.g.Pilocarpine 2%: Contracts ciliary muscle and facilitate

drainage of aqueous humour/ causes miosis (3rd line agent)

A 22 year old male with known cerebral palsy presented to ED with a seizure. He complains of worsening headache and is known to have VP shunt. His observations are stable and GCS15.

1. List the 3 most likely causes of worsening headache in this man? (2 marks)

developing hydrocephalus due to shunt blockade (shunt malfunction or infection) intracranial trauma OR infection (either answer acceptable)

2. How do you interpret shunt function after locating and pressing the chamber? (2 marks)

Difficulty compressing the chamber indicates distal flow obstruction slow refill, defined as refill requiring >3 seconds after compression, generally

indicates a proximal obstruction

NB compression is inaccurate in identifying shunt obstruction

3. What 2 radiological investigations will you arrange for a suspected blocked VP shunt. Explain your rational for each (2 marks)

shunt series of plain from skull to abdomen (for ventriculoperitoneal shunts) will identify kinking, migration, or disconnection of the shunt system.

Brain CT is required to evaluate ventricular size .Comparison with previous CT scans is needed, because many patients with shunts have an abnormal baseline ventricular size..

3. The neurosurgical registrar asks you to perform a shunt tap. Outline the steps (2 marks)

Consent/ explain to patient Locate site over the valve system PPE with sterile gloves and gown Sterile field with antiseptic A 23-gauge needle or butterfly attached to a manometer is inserted into the

reservoir

4. What are the possible outcomes of the shunt tap and what is their significance? (2 marks)

If no fluid returns or flow ceases, a proximal obstruction is likely. The opening pressure should be measured while the reservoir outflow is occluded.

An opening pressure of ≥20 cm H2O (normal 12 ± 2 ) indicates a distal obstruction, whereas low pressures indicate a proximal obstruction.

A 65 year old male attends complaining of loss of vision in his left eye.

a. Give six features you would enquire about in the history. (3 marks)

Visual acuityFlashers/floaters/ amaurosis fugaxtraumaheadache/temporal pain/ systemic upsetneurological signs or symptomseye painprevious medical history e.g. AF, TIA

b. List 2 abnormalities of the fundus shown in the picture above. (2 marks)

Venous engorgement and widespread haemorrhage. Sunset appearance

c. What is the diagnosis? (2 marks)

Central retinal vein occlusion

d. Give 6 associations of this condition. (3 marks)

Trauma- closed headVasculitisHypercoaguability statesHypertensionDMAlcohol Glaucoma

A 28 year old man has been out kite surfing and was thrown into the water at high speed. He is brought in on a spinal board with C-spine protection. He is intubated and ventilated and put on a propofol infusion.

His observations are: Pulse 65 /min, BP 90/60 mmHg and he is warm and well perfused.

The C-spine film and tomogram are shown below.

a. Describe 3 abnormalities on the x-ray. (3 marks)

# body C4, loss of space C3-4, probably soft tissue swellingBurst fracture

b. Describe 2 aspects of his cardiovascular status. (2 marks).

Hypotensive and bradycardic/normocardic

c. What is the likely diagnosis? (2 marks)

Spinal shock

d. What 3 signs would support this? (3 marks)

priapismPink, well perfused peripheries, flaccid paralysis below level C4, increased tendon jerk reflexes below that level (might be absent initially) loss of sensation, very weak respiratory effort,

. A 25 year old man is brought into your regional ED after a bicycle accident. He is not moving his legs and has limited upper limb movement. He has a soft stridor.

His vitals are:GCS 14P 62 /minBP 80/40 mmHgSats 95 % 10L O2

A CT neck is done as part of his assessment.

a. Describe the major abnormalities. (3 marks)

Bilateral facet dislocation atC6/7 with posterior displacement by one vertebral width and spinal cord impingement. Large haematoma anterior to C5-T3 causing tracheal and airway compression at subglottic and glottis level

b. Outline your management of his airway and breathing. (7 marks)

Needs airway soon but not NOW. Potentially difficult ++ MILI and gentle technique mandatory Careful planning preO2 as much as possible Support BP: fluids then pressors as likely neurogenic shock (must have pressor available if not given pre induction). Induction drug must be HD Ok (eg ketamine fentanyl, not big dose props) Mandatory backup surgical option considered Options depend on access in institution ; thus OT with fibreoptic/gas; definitie trache primarily with ENT; glidescope in ED with bougie etc. Consider other injuries in decision making

An 18 year old factory worker is rushed to ED having sustained a chemical burn to his eye. He thinks the chemical had ammonia in it. It is now 20 minutes since the accident.

His eye is pictured here.

a. Describe the picture. (3 marks)

There is marked clouding/opacification of the entire cornea, limbal ischaemia (must note), conjunctival haemorrhage, swelling, inflammation, inflammation of the eyelid tissues. These features are consistent with a significant/severe alkali corneal chemical burn.

(3 marks) – Must include limbal ischaemia or whitening around cornea, conclude a severe or significant alkali burn.

b. What is your immediate management? (4 marks)

1. Copious Irrigation – water, normal saline, continuous, high volume, aim for pH <8 (may say 7.5) on litmus paper.2. Analgesia – topical amethocaine or equiv, systemic titrated to pain score(3. Treat associated burns (skin, other eye))4. Refer Opthalmology given severity of burn

c. Name 3 things you would do to assess this injury, including prognostic indicators. (3 marks)

1.Hx – collateral history, confirm chemical involved – industrial alkali?2. Exam – slit lamp -assess for limbal ischaemia (prognostic indicator), depth of burn(pH if not mentioned above, litmus paper)3. Visual acuity

A 65 year old man with insulin dependent diabetes mellitus presents to the ED with a marked sudden decrease in vision.

a. What are your top 6 differential diagnoses? (3 marks)

Central retinal artery occlusion - mandatoryCentral retinal vein occlusion - mandatoryRetinal detachment - mandatoryVitreous haemorrhage - mandatoryOptic neuritisLoss of contact lensCranial nerve palsy causing diplopiaGiant Cell arteritisToxic metabolic neuropathy/any post chiasmal cause e.g. CVA, acute glaucoma/local trauma etc

b. What are the key historical features you would ask for to help differentiate between these? (7 marks)

Monocular vs binocular- Moncular – ophthalmologic cause- Binocular- central cause – need stroke workup

Painful vs painless visual loss - Painful favors acute glaucoma, optic neuritis and iritis

Sudden onset profound loss in CRAO- often preceded by episodes of amaurosis fugax - occurs over secondsSpectrum of loss in CRVO

- variable extent: blurring to complete monocular vision loss- more gradual onset than CRAO

Photopsiae/floaters- with retinal detachment and vitreous haemorrhage- associated with underlying diabetic retinopathy- decreased central/peripheral deficit e.g. dark curtain in visual

fieldDiplopia

- with diabetic cranial nerve palsy- vascular compromise of cranial nerves to EOM

- direction of gaze producing symptom gives clue to nerve affected

A 60 year old female presents to ED with a painful red eye. There is no history of trauma.

a. What features on history and examination would you expect in acute closed angle glaucoma? (3 marks)

History- Severe unilateral pain- Nausea +/- Vomiting- Reduced vision and halo’s- Known Glaucoma- Absence of trauma- Presence of risk factors; e.g anticholinergic drugs, mydriatics,

age, family history, known shallow anterior chamber

b. You diagnose acute closed angle glaucoma. Outline your management. (7 marks)

Antiemetic e.g ondansetron 4mg IV - mandatoryAnalgesia likely opiate - mandatoryAcetazolamide 500mg IV then 250mg PO tds – mandatoryPilocarpine 2% every 5 min for 1hrTimoptol 0.5% every 30-60minsConsider mannitolUrgent Opthalmology consultation – mandatory

. A 48 year old man is brought by ambulance to your tertiary ED following a collapse at home. GCS on arrival is 3. He is immediately intubated and ventilated before CT scanning of his head and neck. CT reveals a massive intraparenchymal haemorrhage with obstructive hydrocephalus. The neck CT scan is normal. He was previously well on no medication. His partner is present and requests information about his treatment and prognosis.

His observations are:HR 60 /minBP 180/110 mmHgO2 sats 100 %Temp 36.3 °C

Old Format QuestionDescribe your management (100%)

No model answer provided

New Format questionsa. What are your management priorities?

No model answer provided

b. List and justify 4 other investigations you would perform.

No model answer provided

c. Describe 5 urgent interventions you would perform.

No model answer provided

d. What are the principles for gaining consent for organ donation?

No model answer provided

A 29 year old man has been brought to your hospital after being hit to the head by a baseball bat.He has no prior medical history.His vital signs on arrival to the ED are:GCS 11 E2 V2 M5Pulse 110 /minBP 110/65 mmHgO2 sats 99% 6L O2 via maskA CT scan of his head has been performed.

1. List 5 abnormalities on the CT slice. (5 marks)________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2. List your treatment priorities in the ED. Where appropriate, give end-points. (9 marks)________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

1.Large extradural haematoma – high density bi convex lesion left temporal regionHyperacute extradural with “swirl sign” mixed densityLarge scalp haematoma left temporal regionParietal cerebral contusion leftSignificant midline shift to rightLoss of sulci and gyri consistent with raised intracranial pressurePass 3 of 52.Immediate neurosurgical referral for surgical drainage of haematomaIntubation for airway control and management of CO2Maintain MAP >80 (accept approx.) mmHg with IV N/S +/- noradrenaline infusionMaintain oxygenation sats >95%Ventilate for low normal CO2 (35 – 40)Other neuroprotective measures (max 4 marks)Well sedated, paralysedSlightly head-up positionLoosen ties / restriction to venous returnNa high normal rangeNormothermianormoglycaemiapass 5 of 9total pass 8 of 14 corrects to 5.5/10_

A 65 year old man has presented to the ED with a painful left eye. The pain developed over 30minutes while he was at the movie theatre.A clinical photo of his right eye is given.

1. List 3 abnormalities in the clinical photo. (3 marks)____________________________________________________________________________________________________________________________________________________________________2. Give your clinical impression of the photo. (2 marks)__________________________________________________________________________________3. List 3 specific treatment steps for this patient. (3 marks)______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________4. List 2 supportive treatment steps for this patient. (2 marks)__________________________________________________________________________________

1.Cloudy corneaMid-sized pupilCiliary injection, especially laterallyPass 2 of 32.Acute angle closure glaucoma

Pass 2 of 23.Early ophthalmological review - laserIV acetazolamideTopical pilocarpine to constrict pupilTopical apraclonidineTopical beta blockerPass 2 of 34.AnalgesiaAnti-emeticPass 1 of 2Total pass 7/10

Question 7:Whist restraining a 47yo male with a convulsive seizure a nurse was kneed in the cheek, including the orbit and nose. She experienced immediate epistaxis, facial pain and visual blurring. (photo)

(a) Assuming that this is an isolated facial injury without loss of consciousness, list six potential immediate ocular complications that you would exclude. (25%)

(b) What non-occular complications would you seek to exclude? (25%)(c) Describe your management of a probable acutely fractured nose. (25%)(d) What are the clinical signs of orbital compartment syndrome? What is the

immediate management? (25%)

Answers7a. Globe rupture, hyphaema, retinal tear and detachment, vitreous

haemorrhage and detachment, choroidal tear/rupture, iris injury, traumatic iritis, lens detachment, corneal abrasion, commotion retinae, orbital fracture, orbital compartment syndrome, orbital content entrapment in the fractured orbital floor.

7b. Inferior orbital nerve injury (sensory loss), nasal septal haematoma (fractured nose), depressed fractured maxilla), orbital floor fracture and entrapment of orbital fat (enophthalmos) and inferior rectus (diplopia). Pass = 4 complications

7c. Analgesia, control epistaxis, exclude/drain septal haematoma, only image in the context of surveying for facial fractures, exclude orbital injury and inferior orbital nerve injury, no evidence for antibiotics but argued for and given by many on risk of severe infection (divided debate), Pass must be reasonable and include exclude/drain septal haematoma, no imaging unless excluding facial fractures

A 70yo female attends with acute, non-traumatic painless right unioccular blindness.

(a) List 5 potential aetiologies for this presentation (50%)(b) What are the clinical features that would suggest Giant Cell Arteritis? (30%)(c) What is the treatment for Giant Cell Arteritis? (10%)(d) What are the complications of delayed treatment of Giant Cell Arteritis?

(10%)

Answers (9)9a. Complications: Includes, central retinal artery thrombosis,

Ischaemic Central Retinal vein Thrombosis, Optic neuritis (MS, autoimmune, HSV), Retinal detachment, vitreous haemorrhage, ischaemic optic neuropathy, Giant Cell/temporal arteritis, Drugs (phosphodiesterase-5 inhibitors such as Viagra), migraine

Marking (a) : 10% each up to 50%

9b. Clinical features:

Rare under 50yo, peaks in 8th decade, median age of onset 75.

3.7 female: 1male.

Increased risk (x6) in smokers

Usually has prodromal symptoms days to weeks: headaches (72%), polymyalgia (neck, shoulder girdle, pelvis, malaise, weight loss, jaw and oropharyngeal claudication, limb claudication.

Visual : amorous fujax, diplopia, blurring,

Clinically inflamed temporal artery

Carotid tenderness (15%)

Fundoscopic changes of retinal ischaemia delayed 36hrs

Occasional diplopia and, ptosis and miosis

Marking (b) 30% of total score for this question: Pass (15%) but must include both ophthalmic and non-ophthalmic features, including headache, oropharyngeal claudication. Add 5% for each additional feature up to 30% total

9(c). Tx:

Prednisolone initiate at 1mg per Kg (or equivalent dose methylprednisolone) prior to histological confirmation by Temporal artery biopsy.

Marking (c) 10% of total score for this question. Pass/Fail only: Early high dose steroid

9d. Complications

(i) Ophthalmic complications

- Visual loss (retinal/optic infarction)

(ii) Non-ophthalmic complications:

- Cerebral ischaemia, - mesenteric ischaemia, - limb ischaemia, - aortic rupture, - renal infarction, - death.

Marking (d) 10% of total score for this question: Pass (5%) must include visual loss, and two others, add 3% for another and another 2% for a 5th

Overall pass = Total >60%

A 22yo female attends with a sudden onset severe unilateral headache.(a) What features on history and examination support the diagnosis of Acute Sub-

arachnoid Haemorrhage? (20%)(b) What features support the diagnosis of hemicrania? (20%)(c) What is the optimal timing for an LP to exclude the diagnosis of SAH? (10%)(d) Describe your procedure/technique for lumbar puncture. (30%)

The LP result (after a negative CT for SAH) follow:

(e) What is the next step in the diagnostic work up given this result? (20%)

Answers(a) What features on history and examination support the diagnosis of Acute Sub-

arachnoid Haemorrhage? (20%)

Marking. 20% of the total for question 15

Past history of SAHPregnancyPolycystic kidneysFamily historyAbrupt onsetSyncope at onsetNew neurological deficitSevereOccipital/nuchalEvidence of meningism (photophobia, neck stiffness)

Marking. 20% of the total for question 15

2% per feature up to 20%

(b) What features support the diagnosis of hemicrania? (20%)

Past history of hemicraniasSevereUnilateral, Ophthalmic division of trigeminal nerve

Epiphoria and corneal injectionHighly responsive to IndomethacinMultiple episodes per day

Marking. 20% of the total for question 15

4% per feature up to 20%

(c) What is the optimal timing for an LP to exclude the diagnosis of SAH? (10%)

After 11 hours from symptom onset to allow for development of xanthochromia

Marking. 10% of the total for question 15

(d) Describe your procedure/technique for lumbar puncture. (30%)

Essential items : Consent, sterile technique, patient positioning, landmarks, at least 3 numbered tubes in sequence, reinsert stylete prior to withdrawal of LP needle, time-out, local anaesthetic, manometry, tests requested.

Marking. 30% of the total for question 15

Pass = 15% which requires all of the bold.

Add 5% for each extra item as above, up to 30%

(e) What is the next step in the diagnostic work up given this result? (20%)

Refer to neurosurgery & CT angiographyMarking. 20% of the total for

question 1510% for each

Overall pass = 60%

You have intubated a patient with a severe head injury from an assault.His CT is attached.

(a) List the abnormalities on this CT (50%)(b) Would you provide seizure prophylaxis? (20%)(c) Outline your management and define your physiological targets in the initial

resuscitation for this presentation. (30%)

Answers(a) List the abnormalities on this CT (50%)

Penetrating head injury right parietotemporalDepressed skull fracture at the site of the penetrating injuryAir within the craniumEffacement of the right lateral ventricleOverlying scalp laceration/defect

Marking. 25% of the total for question 17

(b) Would you provide seizure prophylaxis? (20%)

Yes. Penetrating head injury. Depressed skull fracture.

Marking. 25% of the total for question 17

Pass/fail (zero)

(c) Outline your management and define your physiological targets in the initial resuscitation for this presentation. (30%)

Normalize CO2, PaO2, BP, BSL, temperatureNurse at 30degrees head upC-spine precautions and clearance by CTTetanus prophylaxisIV antibiotics eg Cefazolin and gentamicinAnalgesia and sedation (eg midazolam and morphine or morphine and propofol)Anticonvulsant eg levetiracetam, valproate, phenytoin

Marking. 25% of the total for question 17

Pass = 15% (must include bolded 5% per item) plus 2% for each additional

Overall pass = 60%