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evidence for the use of aspirin in GCA is anecdotal but might reduce the risk for future cardiovascular events or complications.

Course. Blood results were significant for an ESR of 16 mm/hr and a CRP 2.8 mg/dl (<1.5 normal). The patient was started on oral prednisone 100 mg per day. A temporal artery biopsy was performed despite the normal ESR and showed granulomatous arteritis on the biopsy. The patient was slowly tapered down on the prednisone over an 18-month duration and did not suffer any visual loss or other complications of therapy.

REFERENCES

Lee AG, Brazis PW. (2006) Case studies in neuro-ophthalmology for the neurologist.

Neurol Clin 24:331–345.

Lee AG, Brazis PW. (1999) Temporal arteritis: A clinical approach. J Am Geriatr Soc 47:1364–1370.

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16

Acute Bitemporal Hemianopsia

CASE NO. 16

A 56-year-old previously healthy man had been a passenger in a car driven by his son when he suddenly complained of headache, blurred vision and feeling dizzy. Shortly after this complaint, he lost consciousness and his son drove him directly to the Emergency Room. His level of consciousness improved and he was brought to the Neuro-Ophthalmology Clinic for further evaluation. On examination, his visual acuity was 20/80 OD and 20/60 OS. There was no relative afferent pupillary defect. Fundus examination showed normal discs (Figs. 16.1, 16.2). The initial consulting ophthalmologist had seen the patient and recommended that he be sent to the eye clinic when stable for a formal visual field. At the bedside, however, the neuro-ophthalmologist performed confrontation testing that suggested a bitemporal hemianopia. Three weeks later a formal Goldmann perimetry, however, confirmed the bitemporal hemianopsia.

Dr. Lee. The acute onset of headache and a bitemporal hemianopia implicates a lesion at the level of the optic chiasm. The life-threatening etiologies for an acute chiasmal syndrome include suprasellar aneurysm and pituitary apoplexy. Chiasmal neuritis could produce the visual field defect and pain but the loss of consciousness suggests a rapidly expanding lesion. Pituitary apoplexy is an emergency because of the associated panhypopituitarism and potentially lifethreatening cortisol deficiency which might require emergent admission and hormone replacement. Surgical decompression might

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Fig. 16.1. Color picture of the right fundus.

Fig. 16.2. Color picture of the left fundus.

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be urgently required as well for a rapidly expanding lesion producing other neurologic deficit (e.g. loss of consciousness as in this case). Although an MRI is generally superior to a CT scan for sellar lesions, a CT scan is faster to obtain and might show hemorrhage from apoplexy that might allow earlier diagnosis and treatment for the patient. The important points for the ophthalmologist are that an acute painful bitemporal hemianopia should be imaged emergently even if the imaging is to be done after working hours or over the weekend and that patients with apoplexy need admission and evaluation for panhypopituitarism and other endocrine dysfunction. The key for the ophthalmologist seeing a patient at the bedside is to perform a confrontation visual field to confirm that the visual field defect is bitemporal and thus localizing. Waiting for the patient to have a formal perimetry out of convenience or delaying the diagnosis while waiting for the patient to be stable enough for transportation to the clinic is not recommended.

Dr Brazis. We warn all patients known to have a pituitary tumor about the possibility of pituitary apoplexy, i.e. sudden expansion of the tumor by ischemia or hemorrhage, and document this warning in the patient’s chart. Patients with known pituitary tumors are instructed go to the emergency room immediately if they suffer any sudden, excruciating headache, sudden visual loss, or sudden diplopia. Emergency hormonal replacement and neurosurgical procedure may be live saving.

Course. Cranial CT and MR scans showed a pituitary mass with hemorrhagic components (Figs. 16.3 to 16.7). His son reported in retrospect that the patient had been seen in follow up for a benign “brain tumor” in the past but the surgeons had told him that it did not need surgery yet and his last cranial MRI performed two months ago showed no change. A CT scan in the ER showed a pituitary mass with areas of high density suspicious for a bleed (Figs. 16.3, 16.4).

The patient underwent trans-sphenoidal decompression of his pituitary tumor with secondary apoplexy and recovered completely.

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Fig. 16.3. Non contrast CT head showing a mass labeled with an arrow.

Fig. 16.4. CT head showing areas of high density and low density within the mass.

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Fig. 16.5. Axial FLAIR MRI showing a large mass with areas of high and low signal within the sella consistent with a pituitary lesion.

Fig. 16.6. Saggital MRI showing a large mass with rim enhancement and areas of high and low signal within suspicious for hemorrhage.

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Fig. 16.7. Coronal MRI showing a large mass with rim enhancement and areas of high and low signal within suspicious for hemorrhage.

Fig. 16.8. Goldmann perimetry of the right eye showing some inferonasal depression.

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