A case of Hickam's dictum in a presenting third nerve palsy

Temporal arteritis presenting as third nerve palsy - a case report and review of literature

Giant Cell Arteritis (GCA), also known as Temporal Arteritis, is a type of large vessel vasculitis primarily affecting the elderly population. It typically manifests with headaches, visual impairment, and jaw claudication. Although third nerve palsy as the primary presentation of GCA is rare, it has been reported in previous instances. In this report, we describe the case of a patient presenting with pupil-sparing third nerve palsy, ultimately diagnosed with GCA, and successfully managed with steroids and tocilizumab. A lady in her 80s with past medical history of well-controlled hypertension, bladder cancer in remission, a twenty-pack year smoking history, cervical and lumbar spine stenosis, and recent immunizations presented with acute onset of right-sided pupil-sparing third nerve palsy. Labs were pertinent for an elevated ESR and CRP. Brain imaging was without acute abnormalities. A temporal artery biopsy established evidence of healed arteritis and a diagnosis of GCA was made. The patient was treated with pulse-dose steroids followed by an oral steroid taper and tocilizumab. At one month follow-up, there was partial resolution in her ophthalmoplegia. We underscore the importance of considering temporal arteritis as a potential cause of third nerve palsy in the elderly before attributing it solely to microvascular ischemia, particularly in patients with constitutional features. Additionally, in our comprehensive literature review, we aim to consolidate the existing data from similar presentations, shedding light on the clinical manifestation and disease trajectory.

Importance of the "Rule of the Pupil" in the Modern Neuroimaging Era

ABSTRACT

The "Rule of the Pupil" states that when aneurysms compress the oculomotor nerve, a dilated or sluggishly reactive pupil will result. In previous decades, when cerebral angiography was required to detect an intracranial aneurysm, the "Rule of the Pupil" was used to determine the relative risk of angiography and the likelihood of aneurysmal compression in patients with third nerve palsies (3NPs). Noninvasive imaging including computed tomography angiography (CTA) and magnetic resonance angiography has become readily accessible and can detect all aneurysms large enough to cause 3NPs. It is therefore recommended that all patients with 3NP undergo neuroimaging regardless of pupil status because the consequences of missing an aneurysm are high. The question therefore remains as to whether the "Rule of the Pupil" still has relevance in today's era of modern neuroimaging. We describe a 73-year-old man who developed a left complete, pupil-sparing 3NP and was found to have a paraclinoid meningioma in the left cavernous sinus. As compressive lesions are expected to impair the iris sphincter muscle, no intervention was recommended and his 3NP spontaneously improved within 3 months. We also describe a 54-year-old woman with diabetes and a complete 3NP with a dilated, nonreactive pupil. Initial CTA was reported as normal, but re-review of imaging revealed a posterior communicating artery aneurysm and immediate intervention to coil the aneurysm occurred. The "Rule of the Pupil" is still important in the modern neuroimaging era as demonstrated in cases of incidentally found lesions along the course of the oculomotor nerve and missed radiological findings.