Really painful double vision.

A 67-year-old woman with a history of chronic headache and recent removal of two squamous cell lesions from her forehead presented with left facial pain and diplopia. A diagnosis of Tolosa-Hunt syndrome was made based on clinical presentation and imaging studies. When the patient did not respond to steroids, further studies were done, including biopsy, which revealed perineural spread of squamous cell carcinoma.

Ocular motility review for 1997-1998: part II.

Each year brings new scientific knowledge that builds on itself in a geometric fashion. Ocular motility basic and clinical neurosciences continue to advance with this accelerating pace. The years 1997 and 1998 brought new knowledge to the motility world. This review focuses on the clinical advances within this realm. Part I of this review appeared in the June 2000 (20:2) issue.

Ocular motility review for 1997-1998: part I.

Each year brings new scientific knowledge that builds on itself in a geometric fashion. Ocular motility basic and clinical neurosciences continue to advance with this accelerating pace. The years 1997 through 1998 brought new knowledge to the motility world. This review focuses on the clinical advances within this realm, presented in supranuclear to myopathic organization. Part II of this review will appear in the September 2000 (20:3) issue.

Internuclear ophthalmoplegia after coronary artery catheterization and percutaneous transluminal coronary balloon angioplasty.

A retrospective chart review was performed for identification of patients with isolated internuclear ophthalmoplegia (INO) postcardiac catheterization from two neuro-ophthalmology units. Of the 110 patients with a diagnosis of INO who were evaluated during the observation period, five patients (4.5%) demonstrated relatively isolated INO occurring in the perioperative period of a cardiac endovascular procedure. These five patients underwent diagnostic catheterization alone (three patients), balloon angioplasty (one patient), or stent placement (one patient). All patients improved, with resolution of diplopia in primary position after a mean period of 82 days. The occurrence of INO in the postcardiac catheterization setting is not uncommon, and it appears to be related to dorsal pontine ischemia. The pontomesencephalic medial longitudinal fasciculus is supplied by small-caliber perforating end-arteries from the basilar trunk, which increases selective vulnerability of this area. Cardiac catheterization may precipitate microemboli involving these vessels, leading to internuclear ophthalmoplegia.

Optic nerve enhancement on magnetic resonance imaging in arteritic ischemic optic neuropathy.

Although optic nerve enhancement may be seen in magnetic resonance imaging of radiation-induced ischemic optic neuropathy, similar enhancement in ischemic optic neuropathy has not been previously reported in the English-language neuroophthalmologic literature. We report three cases of optic nerve enhancement in biopsy-proven arteritic ischemic optic neuropathy. Clinicians should consider giant cell arteritis in the differential diagnosis of an optic neuropathy with optic nerve enhancement on magnetic resonance imaging.

The predictive value of CSF oligoclonal banding for MS 5 years after optic neuritis. Optic Neuritis Study Group.

The predictive value of CSF oligoclonal banding for the development of clinically definite MS (CDMS) within 5 years after optic neuritis was assessed in 76 patients enrolled in the Optic Neuritis Treatment Trial. The presence of oligoclonal bands was associated with the development of CDMS (p = 0.02). However, the results suggest that CSF analysis is only useful in the risk assessment of optic neuritis patients when brain MRI is normal and is not of predictive value when brain MRI lesions are present at the time of optic neuritis.

Long-term tamoxifen citrate use and potential ocular toxicity.

PURPOSE: To estimate the prevalence of abnormalities in visual function and ocular structures associated with the long-term use of tamoxifen citrate. METHODS: A single-masked, cross-sectional study involving multiple community and institutional ophthalmologic departments was conducted with a volunteer sample of 303 women with breast cancer currently taking part in a randomized clinical trial to determine the efficacy of tamoxifen (20 mg/day) in preventing recurrences. Participants included women who had never been on drug (n=85); women who had taken tamoxifen for an average of 4.8 years, then been off the drug for an average of 2.7 years (n=140); and women who had been on tamoxifen continuously for an average of 7.8 years (n=78). Women were evaluated by questionnaire, psychophysical testing, and clinical examination to determine any abnormalities in visual function and the comparative prevalences of corneal, lens, retinal, and optic nerve pathology. RESULTS: There were no cases of vision-threatening ocular toxicity among the tamoxifen-treated participants. Compared with nontreated participants, the tamoxifen-treated women had no differences in the activities of daily vision, visual acuity measurements, or other tests of visual function except for color screening. Intraretinal crystals (odds ratio [OR]=3.58, P=.178) and posterior subcapsular opacities (OR=4.03, P=.034) were more frequent in the tamoxifen-treated group. CONCLUSIONS: Women should have a thorough baseline ophthalmic evaluation within the first year of initiating tamoxifen therapy and receive appropriate follow-up evaluations.

Use of pattern electroretinography to differentiate acute optic neuritis from acute anterior ischemic optic neuropathy.

The transient pattern electroretinogram (PERG) was recorded from 16 patients with acute optic neuritis and from 13 patients with acute non-arteritic anterior ischemic optic neuropathy (AION). All patients were tested within 35 days from the the onset of visual symptoms and all had significant central visual field abnormalities in their affected eyes as quantified by automated perimetry. Analysis of the PERGs showed that the amplitude of the N95 peak was abnormally reduced for each eye affected with AION while it remained normal in optic neuritis. No significant alteration in P50 amplitude was observed in either condition. The loss of N95 amplitude in AION was highly correlated with the average depth of visual field loss (in decibels) within a radius of 10 degrees of fixation. These results suggest that PERG could be used early in the course of optic neuropathy to distinguish optic neuritis from AION in those cases for which the diagnosis is still uncertain after the clinical examination.

Recent advances in neuro-imaging and the impact on neuro-ophthalmology.

Neuro-imaging is an essential part of the evaluation in patients with neuro-ophthalmologic disorders. Over the last two decades enormous advances in this area have been made allowing noninvasive evaluation of the orbit and brain. The idea of using nuclear magnetic resonance technology to produce images rather than the ionizing radiation of computed tomography (CT) began to emerge clinically in the late 1970s and early 1980s. Although the quality of early magnetic resonance imaging (MRI) scans was not much better than CT images, by the early 1990s, it became obvious that MRI had particular strength in identifying lesions in the posterior fossa, and demyelinating plaques. With advances in magnetic strength, computer software, surface coils, contrast medium, and more attention to the basic physics of magnet technology, the clarity of MR images improved dramatically. Recent advances in CT scanning (spiral and three-dimensional CT) and MRI (functional MRI and cine MRI) continue to affect significant changes in the discipline of neuro-ophthalmology. Furthermore, advances in MR angiography promise to allow excellent and noninvasive analysis of the cerebral vasculature. This review highlights the recent advances in neuro-imaging.

The pattern visual evoked potential. A multicenter study using standardized techniques.

The peak latency of the pattern-reversal visual evoked potential is a sensitive measure of conduction delay in the optic nerve caused by demyelination. Despite its clinical utility, the pattern-reversal visual evoked potential has not previously been used in multicenter clinical trials, presumably because of difficulty in standardizing conditions between centers. To establish whether the pattern-reversal visual evoked potential could be adequately standardized for use as a measure in multicenter therapeutic trials for optic neuropathy or multiple sclerosis, stimulus and recording variables were equated at four centers and pattern-reversal visual evoked potentials were recorded from 64 normal subjects and 15 patients with resolved optic neuritis. Results showed equivalent latency and amplitude data from all centers, suggesting that stimulus and recording variables can be satisfactorily standardized for multicenter clinical trials. N70 and P100 peak latencies and N70-P100 interocular amplitude difference were sensitive measures of resolved optic neuritis.

The effect of corticosteroids for acute optic neuritis on the subsequent development of multiple sclerosis. The Optic Neuritis Study Group.

BACKGROUND: Optic neuritis is often the first clinical manifestation of multiple sclerosis, but little is known about the effect of corticosteroid treatment for optic neuritis on the subsequent risk of multiple sclerosis. METHODS: We conducted a multicenter study in which 389 patients with acute optic neuritis (and without known multiple sclerosis) were randomly assigned to receive intravenous methylprednisolone (250 mg every six hours) for 3 days followed by oral prednisone (1 mg per kilogram of body weight) for 11 days, oral prednisone (1 mg per kilogram) alone for 14 days, or placebo for 14 days. Neurologic status was assessed over a period of two to four years. The patients in the first group were hospitalized for three days; the others were treated as outpatients. RESULTS: Definite multiple sclerosis developed within the first two years in 7.5 percent of the intravenous-methyl-prednisolone group (134 patients), 14.7 percent of the oral-prednisone group (129 patients), and 16.7 percent of the placebo group (126 patients). The adjusted rate ratio for the development of definite multiple sclerosis within two years in the intravenous-methylprednisolone group was 0.34 (95 percent confidence interval, 0.16 to 0.74) as compared with the placebo group and 0.38 (95 percent confidence interval, 0.17 to 0.83) as compared with the oral-prednisone group. The beneficial effect of the intravenous-steroid regimen appeared to lessen after the first two years of follow-up. Signal abnormalities on magnetic resonance imaging (MRI) of the brain were a strong indication of risk for the development of definite multiple sclerosis (adjusted rate ratio in patients with three or more lesions, 5.53; 95 percent confidence interval, 2.41 to 12.66). The beneficial effect of treatment was most apparent in patients with abnormal MRI scans at entry. CONCLUSIONS: In patients with acute optic neuritis, treatment with a three-day course of high-dose intravenous methylprednisolone (followed by a short course of prednisone) reduces the rate of development of multiple sclerosis over a two-year period.

Brain magnetic resonance imaging in acute optic neuritis. Experience of the Optic Neuritis Study Group.

OBJECTIVE: Changes in the brain on magnetic resonance images are common in patients with optic neuritis even when there is no other clinical evidence of multiple sclerosis. The current study was designed to determine systematically the prevalence of brain abnormalities on magnetic resonance images in the patients entered into the Optic Neuritis Treatment Trial. DESIGN: Prospective multicenter clinical trial. SETTING: Referral centers. PATIENTS AND METHODS: Brain magnetic resonance images from 418 patients with acute optic neuritis (77% women; mean age, 32.0 years) were evaluated at a central reading center with the use of a standardized classification system (ranging from 0 for normal to IV for most extensive changes). RESULTS: Of the scans, 40.9% were classified as grade 0, 10.8% as grade I, 9.1% as grade II, 6.7% as grade III, and 32.5% as grade IV. For patients with isolated (monosymptomatic) optic neuritis, 26.7% had two or more lesions. CONCLUSIONS: We found a lower prevalence of brain magnetic resonance imaging abnormalities in isolated optic neuritis than previous studies have reported. This likely is due to our study having a higher degree of standardization of patient inclusion criteria, which limited patient selection bias.

The pattern electroretinogram: N95 amplitudes in normal subjects and optic neuritis patients.

Recent work has suggested that the N95 peak of the transient pattern electroretinogram (PERG) may be a more sensitive indicator of the late stages of retinal function prior to optic nerve activation than the P50 peak. In this report, we show that a new measure of N95 amplitude, based on digital filtering methods to identify a non-linear baseline before measurement, greatly reduced the amplitude variation in a population of 50 normal subjects when compared with two other plausible measures. We then used that new measure to follow the time course of N95 amplitudes in 12 optic neuritis patients. It was found that maintenance of a normal N95 amplitude at 6 months after onset of optic neuritis was always associated with excellent clinical recovery as measured by visual fields, acuity, presence or absence of an afferent pupil and optic atrophy, and contrast sensitivity (CS). Loss of N95 amplitude to below laboratory limits of normal was associated with abnormalities in these indicators of visual function. This study supports the idea that the N95 peak represents retinal ganglion cell function.

Improving the reliability of pattern electroretinogram recording.

The pattern electroretinogram (PERG) is a small electrical response of the retina to a reversing checkerboard pattern, usually less than 6 microV in amplitude. Unfortunately, the PERG can be obscured by artifacts such as blinks, eye movements, poor fixation, and amplifier saturation. Amplitude criterion artifact rejection systems found on commercial signal averagers eliminate large amplitude artifacts but are insensitive to small amplitude artifacts associated with amplifier saturation. Such saturation often occurs for several recording sweeps after large amplitude signals such as eye blinks are rejected. The presence of post-saturation artifacts complicates clinical PERG analysis. In this paper we describe procedures to remove these small amplitude artifacts from the PERG. These include computer selection of inputs for averaging and use of tracings with small input numbers to approximate PERG amplitudes. These procedures greatly reduce the variability of PERG amplitudes in the normal population, making PERG amplitude a more reliable clinical measure.

A randomized, controlled trial of corticosteroids in the treatment of acute optic neuritis. The Optic Neuritis Study Group.

BACKGROUND AND METHODS: The use of corticosteroids to treat optic neuritis is controversial. At 15 clinical centers, we randomly assigned 457 patients with acute optic neuritis to receive oral prednisone (1 mg per kilogram of body weight per day) for 14 days; intravenous methylprednisolone (1 g per day) for 3 days, followed by oral prednisone (1 mg per kilogram per day) for 11 days; or oral placebo for 14 days. Visual function was assessed over a six-month follow-up period. RESULTS: Visual function recovered faster in the group receiving intravenous methylprednisolone than in the placebo group; this was particularly true for the reversal of visual-field defects (P = 0.0001). Although the differences between the groups decreased with time, at six months the group that received intravenous methylprednisolone still had slightly better visual fields (P = 0.054), contrast sensitivity (P = 0.026), and color vision (P = 0.033) but not better visual acuity (P = 0.66). The outcome in the oral-prednisone group did not differ from that in the placebo group. In addition, the rate of new episodes of optic neuritis in either eye was higher in the group receiving oral prednisone, but not the group receiving intravenous methylprednisolone, than in the placebo group (relative risk for oral prednisone vs. placebo, 1.79; 95 percent confidence interval, 1.08 to 2.95). CONCLUSIONS: Intravenous methylprednisolone followed by oral prednisone speeds the recovery of visual loss due to optic neuritis and results in slightly better vision at six months. Oral prednisone alone, as prescribed in this study, is an ineffective treatment and increases the risk of new episodes of optic neuritis.

Visual impairment in hysteria.

We have reviewed the charts of 45 neuro-ophthamological patients diagnosed with 79 monocular visual field or visual acuity losses secondary to non-organic etiology. Our aim was to determine the percentage of patients that have improvement in vision. As part of the protocol, all patients had magnetic resonance images, pattern visual evoked potentials, and flash electroretinography in addition to complete neuro-ophthalmological examinations. A single physician performed both the initial and follow-up examinations of all patients. Thirty-three percent of these patients had visual field defects only, 62% had both visual field defects and visual acuity defects, and 5% had only visual acuity defects. After organic disease was ruled out, all were given a timetable for recovery and clear reassurance regarding their prognoses for visual recovery. Seventy-eight percent of these patients showed improvement or were normal, while 22% showed no improvement. Younger patients without obvious psychiatric disorder had better prognoses than older patients.

Breast cancer metastatic to the eye is a common entity.

Breast cancer metastatic to the eye is a common entity occurring in up to 30% of women with metastatic disease. The prevalence of this lesion is not appreciated because of the dominant clinical picture of metastases occurring in other organs. The diagnosis should be suspected in any women with a history of breast cancer and any visual symptoms, particularly metamorphopsia and scotomata. A thorough ophthalmologic evaluation, aided by ultrasonography, computed tomography, or magnetic resonance scanning, usually confirms the diagnosis. Early treatment with radiation therapy can alleviate symptoms and control local disease. The recognition and treatment of this disorder is important in maximizing the quality of life in patients with metastatic breast cancer, especially because newer treatment regimens prolong survival and thereby increase the chances for ocular metastasis.