Shalom E. Kelman

The fellow eye in NAION: Report from the Ischemic Optic neuropathy decompression Trial Follow-up study

PURPOSE To examine the prevalence and incidence of second eye nonarteritic anterior ischemic optic neuropathy (NAION) and associated patient characteristics in patients enrolled in the Ischemic Optic Neuropathy Decompression Trial (IONDT) Follow-up Study. DESIGN Randomized clinical trial with observational cohort. METHODS Patients randomized to optic nerve sheath decompression surgery or careful follow-up had a diagnosis of acute unilateral NAION, visual acuity between 20/64 and light perception, and were aged 50 years or older. Eligible patients who declined randomization or whose visual acuity was better than 20/64 were not randomized but followed as part of an observational cohort. Follow-up examinations took place at 3, 6, 12, 18, and 24 months and annually thereafter. RESULTS Four hundred eighteen patients were enrolled; 258 randomized and 160 observed. Previous NAION or other optic neuropathy was present in the fellow eye of 21.1% (88/418) of patients at baseline. Four patients developed optic neuropathy in the fellow eye at follow up that could not be conclusively diagnosed as NAION. New NAION in the fellow eye occurred in 14.7% (48/326) of patients at risk during a median follow up of 5.1 years. Randomized patients experienced a higher incidence (35/201; 17.4%) than nonrandomized patients (13/125; 10.4%). A history of diabetes and baseline visual acuity of 20/200 or worse in the study eye, but not age, sex, aspirin use, or smoking were significantly associated with new NAION in the fellow eye. Final fellow eye visual acuity was significantly worse in those patients with new fellow eye NAION whose baseline study eye visual acuity was 20/200 or worse. CONCLUSIONS Follow-up data from the IONDT cohort provide evidence that the incidence of fellow eye NAION is lower than expected: new NAION was diagnosed in 14.7% of IONDT patients over approximately 5 years. Increased incidence is associated with poor baseline visual acuity in the study eye and diabetes, but not age, sex, smoking history, or aspirin use.

Confocal laser scanning ophthalmoscope. Reproducibility of optic nerve head topographic measurements with the confocal laser scanning ophthalmoscope.

BACKGROUND Glaucoma is an optic neuropathy in which changes in the appearance of both the optic nerve head and the surrounding tissues are important in both diagnosing its presence and progression. Accurate methods to objectively document the appearance of the optic nerve are necessary. The confocal laser scanning ophthalmoscope (Zeiss) is a new prototype instrument that may have the capability to accurately perform this function. METHODS The authors performed a prospective pilot study evaluating the ability of the confocal laser scanning ophthalmoscope to reproduce three-dimensional optic nerve images. Each retinal image contained 600,000 bytes of information. Thirty discrete images of the right optic nerves of 19 visually normal volunteers were obtained. Depth measurements were compared from the same 100 x 100 micron areas (neighborhoods). RESULTS Image comparisons found the variability of depth measurements for the entire image were within 102 microns (95% confidence interval). Sixty percent of the depth measurements were reproducible within 100 microns. Variability of the depth measurements was greatest where the neuroretinal rim sloped at the edge of the optic cup and lowest in the peripapillary area. CONCLUSION The confocal laser scanning ophthalmoscope has the potential to be a safe, rapid, and reproducible method of imaging ocular structures.

Paraneoplastic Retinopathy Associated with Andretinal Bipolar Cell Antibodies in Cutaneous Malignant Melanoma

Purpose: It has been shown previously that the sera, from patients with visual paraneoplastic syndrome associated with lung cancer, contain immunoglobulins that are reactive with the tumor and with photoreceptor and large retinal ganglion cells. The purpose of this study is to determine the retinal cell population that reacts with immunoglobulins in the sera of patients with melanoma-associated retinopathy. Methods: Clinical and electrophysiologic studies were used to determine the locus responsible for the visual defect in each patient. Sera from two patients with melanomaassociated retinopathy, from a patient with herpes zoster, and from a patient who had a colon tumor were obtained. The sera were incubated with sections of retina obtained from a healthy 3-year-old child who had died of asphyxiation. The tissue sections subsequently were incubated with biotin-labeled anti-human immunoglobulin G, and then with streptavidin-labeled peroxidase. Finally, the tissue sections were developed to show peroxidase activity in the targeted retinal cells. Results: Clinical and electrophysiologic studies were consistent with a defect in intraretinal transmission distal to the photoreceptors. The immunoglobulins from the patients with the melanoma-associated retinopathy reacted selectively with the bipolar cells of the retina; approximately 30% of the bipolar cells were immunoreactive. The sera from the other two patients were not reactive with any of the retinal cells examined. Conclusions: The sera of patients with the paraneoplastic syndrome, melanomaassociated retinopathy, contain high titer immunoglobulins that are reactive only with a subset of the bipolar retinal cells. The clinical, electrophysiologic, and immunologic studies are all consistent with an intra-retinal transmission defect at the level of the bipolar cells.

Optic nerve decompression surgery improves visual function in patients with pseudotumor cerebri.

Papilledema from pseudotumor cerebri can cause severe loss of visual acuity and visual field. We performed optic nerve decompression surgery on 17 patients with pseudotumor cerebri who, despite maximum conventional therapy, developed progressive loss of visual acuity and/or visual field. Postoperatively, visual acuity improved or stabilized in 33 of 34 eyes (97%). Visual fields improved in 20 of 21 eyes that underwent surgery. Optic nerve decompression surgery relieves local cerebrospinal fluid pressure on the optic nerve. Progressive loss of visual function associated with pseudotumor cerebri can be reversed or stabilized with optic nerve sheath decompression surgery.

Septo-optic dysplasia in two siblings.

We treated two siblings, a sister and brother, who had features of septo-optic dysplasia, including bilateral optic nerve hypoplasia, absent septum pellucidum, and partial pituitary insufficiency. Additionally, midline central nervous system abnormalities of the corpus callosum and cerebellum were shown. The familial occurrence of this disorder raises the possibility of autosomal-recessive inheritance.

Laser treatment of macular holes.

Macular holes have not been treated with the laser because of the rarity of subsequent total retinal detachment (RD). The authors attempted to clear the subretinal fluid of the halo by laser coagulation of the rim of the hole. Eighteen eyes with visual acuity of 20/200 or less were treated with a laser and followed for a mean of 34.8 months. Ten eyes (55.6%) improved three to eight lines, five eyes (27.8%) remained the same, and the vision of three (16.6%) deteriorated three to five lines. The best visual results noted in three eyes (20/400-20/70, 20/200-20/80, and 20/200-20/60) correlated with the least late loss of pigment epithelium and pigment migration.

Orbital Roof “Blow-In” Fractures

Seven patients with significant frontal trauma involving the supraorbital region associated with orbital roof “blow-in” fractures were admitted to the Maryland Institute for Emergency Medical Services Systems (MIEMSS) at the University of Maryland Medical System over a 16-month period. High-resolution computed tomography (HRCT) with three-dimensional reconstructions demonstrated a downward displacement of the orbital roof in the absence of any orbital rim discontinuity. Associated findings included contussive and hemorrhagic injury to the ipsilateral frontal and parietal lobes, proptosis, ptosis, chemosis, orbital hematoma, and optic nerve contusion. The only long-term ocular pathology in this group of patients was mild to severe optic atrophy. It is recommended that all patients with frontal bone trauma have thin-cut computed tomographic evaluation of the orbit.

Traumatic trochlear nerve palsy diagnosed by magnetic resonance imaging: case report and review of the literature.

Although head trauma is the leading cause of acquired trochlear nerve dysfunction, it receives little attention in the neurosurgical literature. A case is reported of closed head injury that resulted in a right superior oblique palsy in association with incoordination on the left side. Diagnostic imaging revealed a normal cranial computed tomographic scan and a left dorsal midbrain lesion on magnetic resonance imaging scan. The relevant anatomy is reviewed, as well as the action of the superior oblique muscle, its agonists and antagonists, and the clinical manifestations of superior oblique dysfunction. This case is one of the few we are aware of in which a relatively isolated trochlear nerve palsy is the result of a lesion that can be documented by diagnostic imaging, and the first in which the imaging modality is magnetic resonance imaging scan.

Visual Fields at Follow-up in the Ischemic Optic Neuropathy Decompression Trial. Evaluation of Change in Pattern Defect and Severity Over Time

PURPOSE To evaluate change from baseline to 12 months follow-up in study and nonstudy (fellow) eye visual fields from the Ischemic Optic Neuropathy Decompression Trial (IONDT). DESIGN Randomized controlled trial and observational study. PARTICIPANTS The IONDT enrolled patients >or=50 years with acute nonarteritic ischemic optic neuropathy (NAION). Randomized patients (n = 258) had visual acuity <or=20/64; nonrandomized patients (n = 160) had visual acuity >20/64 or refused randomization. INTERVENTIONS Optic nerve decompression surgery (n = 127) or careful follow-up (n = 131). MAIN OUTCOME MEASURES We measured visual fields at baseline and at 6 and 12 months follow-up. Using a computerized system, we classified visual field defects by pattern, location, and severity. We examined changes over time by treatment group, age, baseline comorbidities, and change in visual acuity. In fellow (nonstudy) eyes, we assessed change by whether NAION was present at baseline and also incidence of NAION by whether a visual field defect was present at baseline. RESULTS We analyzed 245 study eye visual field pairs (179 and 66, randomized and nonrandomized, respectively) for change from baseline to 12 months. We observed significant changes in defect distribution within the central field (P = 0.02) for randomized eyes. Superior and inferior altitudinal defects were less severe at follow-up in both randomized and nonrandomized eyes. We observed an association between change in central field severity and change in visual acuity from baseline (P<0.001 at 6 months; P = 0.01 at 12 months; Kendalls tau-b), but no association between visual field change and treatment group, age, or baseline comorbidities. Superior and inferior visual field defects present at baseline in nonstudy eyes improved at follow-up. Fellow (nonstudy) eyes with normal fields did not have an increased risk of developing NAION compared with eyes with >or=1 defects. CONCLUSIONS Visual fields of NAION patients enrolled in the IONDT were relatively stable from baseline to follow-up. A visual field defect in the nonstudy eye at baseline was not associated with development of NAION during follow-up compared with eyes with normal fields.

Surgical quality assurance in the Ischemic Optic Neuropathy Decompression Trial (IONDT).

The purpose of this article is to report the methods and results of the surgical quality assurance program associated with the Ischemic Optic Neuropathy Decompression Trial (IONDT). A surgical quality assurance committee developed and implemented a quality assurance program for a randomized clinical trial requiring surgical intervention. A surgical technique questionnaire was administered at two times during the study course, and maintenance of surgeon certification required submission and approval of a masked videotape of an optic nerve sheath decompression surgery by each study surgeon. Surgical quality was assessed through completion of surgical report forms and standardized, masked review of operative notes. Rates of compliance and intra- and interreviewer agreement were assessed for each aspect of the program. Twenty-five of 32 surgeons (81%) successfully completed and maintained certification. Item agreement varied from 21-92% among reviewers of satisfactory videotapes and 22-89% on unsatisfactory videotapes. Intrarater agreement for videotape acceptability was 11 of 13 (85%), and for specific surgical steps, 147 of 182 (81%). Operative notes were submitted for 123 of 125 (98%) patients receiving surgery. Interrater agreement on individual items ranged from 73-100%. Classification of individual items was identical on first and second review for 1285 of 1344 (95.6%) items. Overall agreement for individual reviewers was 93.8-97.8%. We conclude that use of a small peer review committee, which developed and oversaw a quality assurance program, allowed for consistent certification and monitoring of surgical performance. This in turn increased the credibility of the IONDT results, which demonstrated no difference in outcome between operated and unoperated groups of patients.