H. Stanley Thompson

The Diagnosis and Prognosis of Atypical Carotid-Cavernous Fistula (Red-Eyed Shunt Syndrome)

Nineteen patients who complained of red eyes had the characteristic clinical signs of an atypical carotid-cavernous fistula. Episcleral veins were dilated, intraocular pressure and episcleral venous pressure were high, and blood filled Schlemms canal during gonioscopy. Most of the patients had mild exophthalmos, but in none was the exophthalmos obviously pulsatile, and in only two patients could a bruit be heard. Orbital echography disclosed either a dilated superior ophthalmic vein or congestion of the orbital soft tissues. Selective carotid angiography, done in seven patients, disclosed the fistula to be a dural-cavernous fistula. The serious complication of the fistulas was open-angle glaucoma resulting from the high episcleral venous pressure. None of the fistulas was treated surgically, but six closed spontaneously and three closed soon after carotid angiography.

How to measure the relative afferent pupillary defect.

Abstract The accurate measurement of pupillary defects is of value in following patients with optic nerve disease, as well as for comparing patients, groups, diseases and tests. The numerous problems encountered in measuring the pupil are considered, and a measurement technique using neutral density filters with the swinging light test is described and illustrated.

Enlargement of the Blind Spot Caused by Papilledema

Blind spot enlargement in papilledema has been attributed to either mechanical disruption of the integrity of the peripapillary percipient elements by the swollen optic disk or to the Stiles-Crawford effect. We investigated the possibility that blind spot enlargement in papilledema is caused, at least in part, by a refractive scotoma due to peripapillary hyperopia. We reduced the enlarged blind spot in a patient with focal peripapillary hyperopia, without papilledema, to near normal size by using progressively stronger plus lenses. Similarly, with the addition of plus sphere, we reduced the size of the blind spot in five of six patients with papilledema, but in none of our normal subjects.Blind spot enlargement in papilledema has been attributed to either mechanical disruption of the integrity of the peripapillary percipient elements by the swollen optic disk or to the Stiles-Crawford effect. We investigated the possibility that blind spot enlargement in papilledema is caused, at least in part, by a refractive scotoma due to peripapillary hyperopia. We reduced the enlarged blind spot in a patient with focal peripapillary hyperopia, without papilledema, to near normal size by using progressively stronger plus lenses. Similarly, with the addition of plus sphere, we reduced the size of the blind spot in five of six patients with papilledema, but in none of our normal subjects.

Relative Afferent Pupillary Defects in Optic Neuritis

We measured relative afferent pupillary defects in 105 patients with various stages of optic neuritis. We detected pupillary defects in 96% of acute unilateral cases, 92% of recovered unilateral cases 91.7% of acute cases with evidence of optic neuropathy in the other eye, and 65.8% of recovered bilateral cases. With careful testing, one can find relative afferent pupillary defects in nearly all patients with unilateral optic neuritis and in most patients with bilateral disease. A patient without a pupillary defect after apparent unilateral optic neuritis frequently has evidence of disease in the other eye when visual-evoked potentials are tested.

Pupil Cycle Time in Optic Neuritis

A thin slit-lamp beam illuminating the pupil margin produced clearly visible pupil oscillations. These oscillations were timed with a stopwatch, thus producing a measurement of the pupil cycle time. The pupil cycle time was remarkably stable in various testing situations and repeatable within +/- 3% over extended periods of time. When the iris muscles were normally innervated and responsive, the pupil cycle time was dependent on the speed of conduction and the number and strength of optic nerve impulses. Pupil cycle time can be measured in most persons with active or inactive optic neuritis. In the few patients whose light reflex is so poor that the pupil cycle time cannot be measured, the inability to induce cycling can itself be taken as a definite abnormality of the light reflex arc. Only 5% of normal persons 12 to 50 years of age are expected to have a pupil cycle time in either eye longer than 954 msec, or a difference in pupil cycle time between the two eyes longer than 70 msec. Pupil cycle time was significantly longer in patients with optic neuritis, with a P-value less than .001. The pupil cycle time is similar to visual evoked response latency time in that it can detect and quantitate subclinical defects in optic nerve conduction time. Pupil cycle time is objective and quantitative for each eye individually. It is a fast, simple, and reliable clinic test of optic nerve function.

Segmental denervation and reinnervation of the iris sphincter as shown by infrared videographic transillumination

OBJECTIVEnThis study aimed to analyze the denervation and reinnervation history of individual segments of the iris sphincter in patients with Adies syndrome.nnnDESIGNnThe irises of these patients were retroilluminated by shining an infrared-rich light through the lower eyelid and sclera and viewing the transilluminated iris from the front with an infrared-sensitive video camera. The irises of the same group of patients also were videotaped through a slit-lamp camera using routine frontal illumination. Both of these techniques also were used to examine a series of normal subjects.nnnPARTICIPANTSnA total of 61 patients with Adies syndrome or Adies-like denervation of the iris sphincter (from surgery, trauma, or radiation) and 10 normal subjects were studied.nnnMAIN OUTCOME MEASURESnSlit-lamp examination results of the segmental movement of the iris were compared to the infrared transillumination pattern of the iris sphincter before and during the light reflex, before and during the near-vision reaction, before and during eye movement, and before and after the application of dilute pilocarpine and 1% pilocarpine.nnnRESULTSnWhenever an iris sphincter segment contracted, it also became denser by using these techniques. Reinnervated iris segments failed to contract to light but did contract and became denser with a near effort or with eye movement. Segments supersensitive to pilocarpine became denser than adjacent segments without supersensitivity, but atrophic-appearing segments looked translucent and thin, failing to become denser, even with 1% pilocarpine.nnnCONCLUSIONSnThe innervational history and current status of each clock-hour segment of the iris sphincter can be determined using this technique of videographic infrared transillumination, and the progression and pattern of iris denervation and reinnervation can be determined in patients with Adies pupil. A miotic Adies pupil that is tonic, even in darkness, was found to be associated with a dense pattern of infrared transillumination in sphincter segments, which the authors interpret as being associated with a rich reinnervation from accommodative fibers. Segments that become densely reinnervated appear to lose their cholinergic supersensitivity.

Horner's Syndrome in Subadventitial Carotid Artery Dissection and the Role of Magnetic Resonance Angiography

PURPOSE/METHODSnA 47-year-old man with a postganglionic Horners syndrome and severe right facial pain was found to have a normal carotid angiogram. We obtained a magnetic resonance angiogram of the neck because of our continued clinical suspicion of dissection.nnnRESULT/CONCLUSIONnAn area of hyperintensity was identified along the lumen of the right internal carotid artery, suggesting a subadventitial dissection. Magnetic resonance angiography is a noninvasive, sensitive technique for identifying some carotid dissections.

Hourglass-shaped Visual Fields as a Sign of Bilateral Lateral Geniculate Myelinolysis

PURPOSE/METHODSnBilateral visual field defects resembling an hourglass could be produced by bilateral lateral geniculate lesions. We recently encountered such deficits in a 37-year-old woman after an episode of central pontine myelinolysis.nnnRESULTS/CONCLUSIONSnAutomated static perimetry demonstrated the congruous visual field defects to involve both halves of the visual field. They were confirmed with kinetic perimetry, and they remained stable for four years. Magnetic resonance imaging demonstrated enhancing lesions characteristic of myelinolysis in each lateral geniculate.

Unilateral Nasal Hemianopia as a Sign of Intracranial Optic Nerve Compression

A 52-year-old woman complained of progressive loss of vision in the right eye. Although the visual acuity was normal, there was a relative afferent pupillary defect, and a mild decrease in color vision, mild optic disk pallor, and a nasal field defect along the central vertical meridian. The left eye was normal. Craniotomy disclosed a giant right-sided carotid-ophthalmic artery aneurysm.