Headache — Viva

Long Case Viva Defence

Candidate's opening statement (model answer)

"Mrs Thompson is a 68-year-old retired teacher who presents with a 6-month history of worsening daily headache, complicated by a new temporal headache and jaw pain on chewing for the past 2 weeks. She has a 20-year history of migraine without aura, type 2 diabetes, and ischaemic heart disease with a prior myocardial infarction 4 years ago. Her medications include metformin, aspirin, atorvastatin, and bisoprolol. [1]

Her main problems are:

1. Chronic migraine with medication-overuse headache — she takes naproxen and a codeine-paracetamol combination daily, and sumatriptan on 3-4 days per week for the past year
2. Possible giant cell arteritis — new temporal headache and jaw claudication at age 68, which must be excluded before accepting any primary headache diagnosis
3. Ischaemic heart disease — contraindicates triptans for acute migraine therapy
4. Type 2 diabetes — complicates steroid therapy if GCA is confirmed
5. Obesity (BMI 32) — relevant to her migraine and to potential IIH in the differential
6. Medication side effects — she is on multiple agents with potential drug interactions [1]

My immediate plan is to screen for GCA urgently with ESR, CRP, and temporal artery assessment, and if positive, start prednisolone immediately. I will simultaneously address the medication-overuse headache through withdrawal and start a CGRP monoclonal antibody as a safe preventive given her ischaemic heart disease. I will involve rheumatology if GCA is confirmed." [1]

Examiner probing questions and model answers

Q1: "Walk me through how you would differentiate between her chronic migraine with medication overuse and giant cell arteritis. Could they coexist?" [1]

"They absolutely could coexist, and that is exactly the clinical reasoning challenge here. The key discriminating features are as follows. Her chronic migraine with medication overuse is characterised by a bilateral, throbbing, daily headache that has evolved from her episodic migraine over years, with documented analgesic overuse — this is a transformation of a pre-existing primary headache. Giant cell arteritis, by contrast, presents as a new or changed headache in a patient over 50, typically temporal and unilateral, with systemic features (fever, malaise, weight loss), jaw claudication, scalp tenderness, and an abnormal temporal artery on examination. The jaw claudication is the single most specific symptom — pain in the masseter on prolonged chewing, relieved by rest, indicating external carotid ischaemia. [1]

In this patient, the new temporal headache and jaw claudication are red flags that mandate investigation for GCA before accepting her daily headache as purely chronic migraine with medication overuse. The SNNOOP10 screen identifies her new headache after age 50 (O), pattern change (P), and systemic symptoms (S) as positive items. My approach is: check ESR and CRP immediately, examine the temporal arteries, arrange temporal artery ultrasound, and if there is any clinical or biochemical suggestion of GCA, start prednisolone 40-60 mg and arrange biopsy within 2 weeks. I will not let the medication-overuse headache diagnosis blind me to a vasculitis that could blind her." [1]

Q2: "Her ischaemic heart disease means she cannot take triptans. How does this change her acute and preventive migraine management?" [1]

"This is a critical constraint. All triptans — sumatriptan, rizatriptan, eletriptan, zolmitriptan — cause vasoconstriction of coronary and cerebral arteries and are absolutely contraindicated in ischaemic heart disease, prior stroke, and uncontrolled hypertension. The same applies to ergotamine. [1]

For her acute attacks, once she has withdrawn from the overused medications, I will use a combination of a high-dose NSAID and an antiemetic — for example, naproxen 500 mg with metoclopramide 10 mg at the onset of breakthrough attacks, limited to 2 days per week. If that is insufficient, I will consider a CGRP antagonist (gepant) such as ubrogepant or rimegepant, which does not cause vasoconstriction and is safe in patients with vascular disease. [1]

For prevention, the CGRP monoclonal antibodies are the ideal choice for this patient. Erenumab 70-140 mg subcutaneously monthly, or fremanezumab 225 mg monthly, target the CGRP pathway without cardiovascular effects. The STRIVE trial showed that erenumab significantly reduced monthly migraine days compared to placebo in episodic migraine. These agents do not cause vasoconstriction, cognitive slowing, weight gain, or bradycardia — all relevant to her comorbidities. If these are not accessible, I would consider candesartan 8-16 mg daily, which is also vascular-safe, or onabotulinumtoxinA injections for chronic migraine." [1]

Q3: "What if her ESR comes back at 22 mm per hour? Does that exclude giant cell arteritis?" [1]

"No, it does not. The ESR can be normal in up to 15 per cent of biopsy-proven giant cell arteritis. A normal or mildly elevated ESR does not exclude the diagnosis. The CRP is more sensitive, and I would check both — if either is elevated, that supports the diagnosis. But the decision to treat must be driven by clinical suspicion, not by a single blood test. If her clinical picture is suggestive of GCA — temporal headache, jaw claudication, abnormal temporal artery on examination — I would start prednisolone despite a borderline ESR and arrange a temporal artery ultrasound (looking for the halo sign) and biopsy within 2 weeks. The biopsy has skip lesions, so even a negative biopsy does not definitively exclude GCA. The 2022 ACR/EULAR classification criteria recognise positive temporal artery biopsy or ultrasound halo sign as the highest-scoring item, but the absolute prerequisite is age over 50, and the diagnosis is clinical with histological support." [1]

Q4: "She has type 2 diabetes. How does that affect your steroid management if GCA is confirmed?" [1]

"High-dose steroids will significantly worsen her glycaemic control. My approach is: first, inform the patient and her diabetes team; second, increase the frequency of blood glucose monitoring (she should check 4 times daily); third, be prepared to uptitrate her metformin and potentially add a short-acting insulin or a sulfonylurea during the high-dose phase; fourth, aim for the shortest possible course of high-dose steroids and taper as quickly as the clinical response allows, guided by symptoms and ESR/CRP. [1]

I would also start bone protection from day one — calcium and vitamin D supplementation, and a bisphosphonate such as alendronate, with a baseline DEXA scan — given the expected prolonged steroid course of 12-18 months. I would add a PPI for gastric protection. If she relapses on tapering and requires prolonged steroids, I would discuss tocilizumab — an IL-6 receptor antagonist licensed for GCA — with rheumatology, as it reduces both the relapse rate and the cumulative steroid dose, and may help with glycaemic control by reducing the steroid burden." [1]

Q5: "How would you manage the medication-overuse headache component, and in what order relative to the GCA workup?" [1]

"The GCA workup takes absolute priority — a potentially blinding vasculitis trumps a chronic headache syndrome. So my first action is the ESR, CRP, temporal artery assessment, and decision on steroids. If GCA is confirmed, the steroids will actually help the headache — high-dose prednisolone is itself a powerful anti-migraine and anti-headache agent, and her daily headache may improve substantially on 60 mg of prednisolone. [1]

Once the GCA situation is managed (or excluded), I address the medication overuse. The approach is: explain the diagnosis, withdraw the overused naproxen, codeine-paracetamol, and sumatriptan (tapering the codeine component), warn her about the 1-2 week withdrawal headache, and start a preventive — the CGRP monoclonal antibody, as discussed. I review at 4-8 weeks to confirm resolution of the medication-overuse headache and to assess the preventive's effect on her underlying migraine. I also address lifestyle factors — regular sleep, trigger identification, weight loss — and provide a migraine diary to track frequency and medication use." [1]

Q6: "What is her long-term prognosis?" [1]

"Her prognosis depends on three factors. First, the GCA — if confirmed and treated promptly, her vision will be preserved, and she can expect a good outcome with a 12-18 month steroid taper, though relapses occur in up to 30 per cent of patients, particularly during the taper. Second, the chronic migraine — with successful withdrawal of the overused medications and effective prevention (CGRP monoclonal antibody), she can expect a significant reduction in headache frequency within 2-3 months. Chronic migraine does not remit completely in most patients, but the goal is to return her to episodic migraine with 4 or fewer headache days per month and restore her functional capacity. Third, her cardiovascular risk — she has ischaemic heart disease and type 2 diabetes, and the avoidance of triptans and the use of vascular-safe preventives (CGRP monoclonal antibody) is part of a broader cardiovascular risk reduction strategy. With good management, her quality of life should improve markedly." [1]

Short Case Discussion

Scenario: "Examine this patient's cranial nerves. She is a 54-year-old woman who has been referred with daily headache and blurred vision for 3 months."

Candidate presentation (model): [1]

"I performed a cranial nerve examination on Mrs Davies. On general inspection she is an overweight woman who appears comfortable. Her visual acuity is 6/12 bilaterally, reduced from her baseline of 6/6 per the referral letter. [1]

Cranial nerve II: On fundoscopy there is bilateral disc swelling with loss of the physiological cup and blurred disc margins, more marked on the right, with flame haemorrhages at the right disc margin. There is no spontaneous venous pulsation bilaterally. Visual fields by confrontation show an enlarged blind spot bilaterally and an inferior nasal defect on the right. [1]

Cranial nerves III, IV, and VI: Eye movements are full, but there is a mild right abducens (sixth nerve) palsy — the right eye fails to abduct fully, with no diplopia in primary position. Pupils are equal and reactive. [1]

The remaining cranial nerves (V, VII, VIII, IX, X, XI, XII) are normal, including normal facial sensation, facial power, hearing, palatal movement, tongue protrusion, and shoulder shrug. [1]

These findings — bilateral papilloedema with an enlarged blind spot, a right sixth nerve palsy (a false localising sign of raised intracranial pressure), and reduced visual acuity — are consistent with raised intracranial pressure, most likely idiopathic intracranial hypertension given her age, sex, and obesity. I would like to examine her blood pressure, check for a bruit over the carotids and temporal arteries, and review her medication history (tetracyclines, retinoids, and vitamin A derivatives can precipitate IIH). My next investigation would be an MRI brain with MRV to exclude a mass lesion and venous sinus thrombosis, followed by a lumbar puncture with opening pressure measurement." [1]

Examiner: "What opening pressure would confirm the diagnosis?" [1]

"The revised diagnostic criteria from Friedman and colleagues in 2013 define the threshold as an opening pressure above 25 cm of water in adults, measured in the lateral decubitus position with the legs relaxed. In this patient, I would expect a pressure of 30 cm of water or above. The LP also serves to confirm that the CSF composition is normal — no cells, normal protein and glucose — which is essential for the diagnosis of idiopathic intracranial hypertension as opposed to a secondary cause of raised pressure such as meningitis or carcinomatous meningitis. The LP also provides temporary therapeutic relief of the pressure, though the effect is often transient." [1]

Examiner: "What is the role of acetazolamide, and what is the evidence?" [1]

"Acetazolamide is a carbonic anhydrase inhibitor that reduces CSF production and is the first-line medical therapy for IIH. The standard starting dose is 500 mg twice daily, titrated up to 1 to 4 grams daily as tolerated. The NORDIC Idiopathic Intracranial Hypertension Treatment Trial, published in JAMA in 2014, randomised 165 patients with IIH and mild visual loss to acetazolamide (titrated up to 4 g daily) versus placebo, both combined with a weight-reduction diet. The trial showed a modest but statistically significant improvement in perimetric mean deviation (the primary outcome), papilloedema grade, and vision-related quality of life in the acetazolamide group. The conclusion was that acetazolamide provides modest benefit when combined with weight loss. The main adverse effects are paraesthesia (a nearly universal effect of carbonic anhydrase inhibition), taste disturbance (particularly for carbonated drinks), fatigue, and nephrolithiasis. The weight loss that accompanies acetazolamide is itself therapeutic — weight loss of 5 to 10 per cent can produce remission of IIH." [1]

Examiner: "When would you consider surgical intervention in IIH?" [1]

"The indication for surgical intervention is progressive visual loss despite maximal medical therapy. The visual loss can be insidious — patients may not notice constriction of their visual fields until it is severe — so serial perimetry and optical coherence tomography are mandatory for monitoring. If there is progressive loss of visual field or acuity despite acetazolamide and weight loss, the options are: first, CSF shunting — a lumboperitoneal or ventriculoperitoneal shunt to divert CSF and reduce pressure; second, optic nerve sheath fenestration — a surgical procedure to slit the dural sheath around the optic nerve and relieve the pressure on the nerve, protecting the remaining vision (often preferred when the visual loss is asymmetric or rapidly progressive); and third, venous sinus stenting — an interventional neuroradiology procedure in which a stent is placed in a stenosed venous sinus, which is increasingly recognised as a treatable mechanism in selected patients with IIH. The choice depends on local expertise, the pattern of visual loss, and whether the predominant problem is headache or visual compromise." [1]