Friday, April 26, 2013
Friday, April 12, 2013
Papilledema and obstructive sleep apnea syndrome.
Abstract
OBJECTIVES:
To characterize the pathogenesis and clinical features of optic disc edema associated with obstructive sleep apnea syndrome (SAS).
METHODS:
A series of 4 patients with SAS and papilledema (PE) underwent complete neuro-ophthalmologic evaluation and lumbar puncture. In 1 patient, continuous 24-hour intracranial pressure (ICP) monitoring was also performed.
RESULTS:
All 4 patients had bilateral PE that was asymmetric in 2. Three patients had optic nerve dysfunction, asymmetric in 1, unilateral in 2. Daytime cerebrospinal fluid pressure measurements were within normal range. Nocturnal monitoring performed in one patient, however, demonstrated repeated episodes of marked ICP elevation associated with apnea and arterial oxygen desaturation.
CONCLUSIONS:
We propose that PE in SAS is due to episodic nocturnal hypoxemia and hypercarbia resulting in increased ICP secondary to cerebral vasodilation. In these individuals, intermittent ICP elevation is sufficient to cause persistent disc edema. These patients may be at increased risk for developing visual loss secondary to PE compared with patients with obesity-related pseudotumor cerebri because of associated hypoxemia. The diagnosis of SAS PE may not be appreciated because daytime cerebrospinal fluid pressure measurements are normal and because patients tend to present with visual loss rather than with symptoms of increased ICP.
Monday, April 08, 2013
Common pitfalls in management IIH
missing venous sinus thrombosis
failure to address other secondary causes (e.g., anemia, hypoxia)
relying on optic disc appearance without monitoring visual fields
being too slow to proceed to surgical intervention