Reid Longmuir

Comparison of the clinical expression of retinitis pigmentosa associated with rhodopsin mutations at codon 347 and codon 23.

PURPOSE To examine the difference in expression of retinitis pigmentosa from mutations at codon 23 and codon 347 or rhodopsin; to report a novel mutation in rhodopsin. METHODS Goldmann perimetry (solid angle of I4e isopter) and electroretinographic amplitudes (square root transform of a response ratio) were analyzed for 24 patients with mutations at codon 347 (15 with Pro347Ala, 2 with Pro347Gln, 6 with Pro347Leu, and 1 with a novel Pro347Cys change) and 41 patients with mutations at codon 23 (6 with Pro23Ala; 35 with Pro23His). RESULTS When all patients with mutations at codons 347 and 23 were compared, loss of visual fields was significantly worse in patients with codon 347 changes (P =.0003). Only rod responses of the electroretinograms were significantly different between the two groups (P =.048). Specific comparison of Pro347Ala with Pro23Ala using regression analysis demonstrated significant differences in severity between codon 23 and codon 347 patients for b-wave amplitudes of rod (P =.0069), cone (P =.039) and maximum combined response (P =.049). The solid angle of the I4e isopter was also significantly different (P =.025) between the groups after controlling for age. Modeling age by group for Pro347Ala comparison produced an R(2) of.44. CONCLUSION We reconfirmed that rhodopsin-related retinitis pigmentosa from mutations involving codon 347 produces a more severe phenotype than that involving codon 23. Accurate modeling of disease was shown to be possible by incorporating the effects of a patients age and specific genotype. Therefore, both of these variables must be considered in prognostic counseling and subject recruitment for future therapeutic trials.

Contact Lens Strategies for the Patient with Dry Eye

Dry eye is the most common reason for contact lens (CL) discontinuation, and the patient with pre-existing dry eye presents particular challenges to the CL fitter. Poor tear film quality/stability, oxygen deprivation, lens deposits, and adverse reactions to CL solutions all contribute to dry eye, and lid disease, allergies, environmental factors, and medications can further hamper successful CL wear by the patient with dry eye. Health and comfort of the ocular surface is affected by the water content, ionicity, oxygen permeability, and modulus of elasticity of the lens, as well as by surface characteristics, such as protein, lipid, and mucin deposition; protein adsorption; and wettability. The choice of CL cleaning solutions with regard to action, cytotoxicity, and biocompatibility are as important as the choice of the CL itself. With appropriate management of the lid, meibomian gland, and ocular surface conditions that produce dry eye, careful selection of lenses and solutions, and vigilant follow-up, successful CL wear should be achievable for the dry eye patient.

Intracranial hypertension in systemic lupus erythematosus

Purpose: Intracranial hypertension (IH) mimicking pseudotumor cerebri (i.e., idiopathic IH) has been reported in individuals with systemic lupus erythematosus (SLE) since the 1960s. Although various mechanisms have been proposed (e.g., venous thrombosis, medication side effect, and immunologic or inflammatory disease) none have been proven to be causal. Methods: Retrospective chart review of patients with IH and SLE at a single tertiary care institution. Results: In a cohort of IIH patients the percentage of patients in our study with SLE was 1% (4 in 410). Three out of the four patients had serologic evidence for a hypercoagulable state but only one had cerebral venous sinus thrombosis. Two patients had onset or worsening of IH in close temporal relationship to steroid withdrawal. The course, treatment, and prognosis of our patients with SLE and intracranial hypertension did not differ significantly from our clinical experience with IIH or with the published natural history data for IIH. Conclusions: The association of SLE and IH may occur more than by chance alone. Steroid withdrawal in the treatment of the SLE may be a predisposing or precipitating factor in the development of IH in these patients rather than the inflammatory effects of SLE per se. The hypercoagulable state in some patients with SLE may also produce cerebral venous sinus thrombosis as an additional potential mechanism of IH.

Visual Loss Due to Wernicke Syndrome Following Gastric Bypass

Purpose: To report a case of Wernicke encephalopathy after gastric bypass surgery resulting in vision loss, ophthalmoplegia, and ataxia, all of which reversed with a single dose of IV thiamine. Methods: Observational case report. Results: A 34-year-old woman presented with decreased vision and intermittent diplopia after gastric bypass surgery. She was found to have bilateral limitation of horizontal gaze, decreased vision with bilateral central scotoma and mild disc edema OU. Her cranial magnetic resonance imaging (MRI) was normal. A presumptive diagnosis of Wernicke encephalopathy was made. The patient was admitted, and a single dose of IV thiamine reversed the ophthalmoplegia and vision loss within 24 hours. Conclusion: Wernicke encephalopathy should be considered in patients with vision loss after gastric bypass surgery. The classic triad of confusion, ataxia, and ophthalmoplegia may not be present and, although uncommon, the findings of optic disc edema and vision loss should not deter the clinician from making the diagnosis. Replacement thiamine if given promptly may rapidly reverse the findings.

Risk factors for poor visual outcome in patients with idiopathic intracranial hypertension

Objectives: Determine potential risk factors for progressive visual field loss in the Idiopathic Intracranial Hypertension Treatment Trial, a randomized placebo-controlled trial of acetazolamide in patients with idiopathic intracranial hypertension and mild visual loss concurrently receiving a low sodium, weight reduction diet. Methods: Logistic regression and classification tree analyses were used to evaluate potential risk factors for protocol-defined treatment failure (>2 dB perimetric mean deviation [PMD] change in patients with baseline PMD −2 to −3.5 dB or >3 dB PMD change with baseline PMD −3.5 to −7 dB). Results: Seven participants (6 on diet plus placebo) met criteria for treatment failure. The odds ratio for patients with grades III to V papilledema vs those with grades I and II was 8.66 (95% confidence interval [CI] 1.65–∞, p = 0.025). A 1-unit decrease in the number of letters correct on the ETDRS (Early Treatment Diabetic Retinopathy Study) chart at baseline was associated with an increase in the odds of treatment failure by a factor of 1.16 (95% CI 1.04–1.30, p = 0.005). Compared with female participants, the odds ratio for male participants was 26.21 (95% CI 1.61–433.00, p = 0.02). The odds of treatment failure were 10.59 times higher (95% CI 1.63–116.83, p = 0.010) for patients with >30 transient visual obscurations per month vs those with ≤30 per month. Conclusions: Male patients, those with high-grade papilledema, and those with decreased visual acuity at baseline were more likely to experience treatment failure. All but one of these patients were treated with diet alone. These patients should be monitored closely and be considered for aggressive treatment of their idiopathic intracranial hypertension.

Retinal arterial but not venous tortuosity correlates with facioscapulohumeral muscular dystrophy severity

BACKGROUND Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal-dominant disease beginning with facial and shoulder girdle weakness with variable progression. Exudative retinal detachment, retinal vessel irregularities on fluorescein angiography, and retinal vessel tortuosity have been found in association with FSHD. METHODS In this retrospective study, muscle affectedness severity was rated as mild, moderate, or severe by a neurologist masked to the retinal images. Three ophthalmologists masked to disease severity graded the degree of arterial and venous tortuosity on a scale of 1 to 4. An automated method estimated an index of tortuosity for arteries and veins from color fundus photographs. Spearman rank correlation coefficients were used to describe the relationship between retinal vessel tortuosity and disease severity. RESULTS Seven patients with an average age of 13 years (range, 7-36 years) were selected. Correlation between the subjective tortuosity for arteries, and the severity of FSHD was 0.78 (p = 0.039). The correlation coefficient for venous tortuosity was -0.06 and was not significant (p = 0.882). The correlation coefficient between the average algorithmic computer-generated tortuosity indices for arteries and FSHD severity was high (0.85, p = 0.016), but for veins it was low and not significant (0.19, p = 0.662). CONCLUSIONS The authors of previous reports have shown retinal vascular abnormalities did not correlate to FSHD disease severity. Our results suggest a correlation between the tortuosity of arteries and the severity of disease in FSHD patients. These results suggest the tortuosity of arteries can serve as a biomarker of severity of disease in these FSHD patients, either as determined by human experts or by an automated method.

Cotton Wool Spots Associated with Interferon Beta-1 Alpha Therapy

Purpose: To describe a case of cotton wool spots associated with interferon beta-1a treatment. Methods: Observational case report. Results: A 40-year-old man with a history of multiple sclerosis was on interferon beta-1a. He presented with cotton wool spots on fundus exam, which resolved and then recurred all while on therapy. Interferon was discontinued after the second episode and again the cotton wool spots resolved. Upon restarting the interferon, no further cotton wool spots have recurred. Conclusion: To our knowledge this represents only the third case of interferon beta-1a associated cotton wool patches and the first in the English-language ophthalmic literature. Unlike interferon alpha therapy, interferon beta 1-a retinopathy is presumed to be extremely rare and more common etiologies for cotton wool spots should be excluded in these patients. Given this limited number of cases versus the relatively frequent use of interferon beta-1a in the management of multiple sclerosis, no conclusions regarding causality or screening can be made but the issue probably deserves further study.

Causes and Prognosis of Visual Acuity Loss at the Time of Initial Presentation in Idiopathic Intracranial Hypertension.

PURPOSE To determine the etiology and prognosis of visual acuity loss in idiopathic intracranial hypertension (IIH) at presentation and to provide objective measures to predict visual outcome. METHODS A retrospective review of 660 patients with IIH (2009-2013) identified 31 patients (4.7%) with 48 eyes having best-corrected visual acuity (BCVA) of 20/25 or worse on initial presentation. Fundus photography, optical coherence tomography (OCT) of the optic disc and macula, and perimetry were used to determine the causes and prognosis of vision loss. Segmentation of the macula OCT was performed using the Iowa Reference Algorithm to determine the retinal ganglion cell-inner plexiform layer complex (GCL-IPL) thickness. RESULTS Outer retinal changes alone caused decreased BCVA at initial presentation in 22 eyes (46%): subretinal fluid in 16, chorioretinal folds in 5, and peripapillary choroidal neovascularization in 1. The vision loss was reversible except for some eyes with chorioretinal folds. Optic neuropathy alone caused decreased BCVA in 10 eyes (21%) and coexisting outer retinal changes and optic neuropathy caused decreased BCVA in 16 eyes (33%). A GCL-IPL thickness less than or equal to 70 μm at initial presentation or progressive thinning of greater than or equal to 10 μm within 2 to 3 weeks compared with baseline correlated with poor visual outcome. CONCLUSIONS Visual acuity loss in IIH can be caused by both outer retinal changes and optic neuropathy. Vision loss from outer retinal changes is mostly reversible. The outcome of patients with coexisting outer retinal changes and optic neuropathy or optic neuropathy alone depends on the degree of optic neuropathy, which can be predicted by the GCL-IPL thickness.

Third nerve palsy as the initial manifestation of giant cell arteritis.

Objective: Giant cell arteritis (GCA) is rarely reported as a cause of third nerve palsy. We describe the presentation and course of patients with third nerve palsy as the sole initial ocular manifestation of GCA. Methods: Retrospective chart review of patients with third nerve palsy as the presenting sign of GCA. Symptoms, signs, and inflammatory marker levels at presentation and on follow-up were analyzed. All patients had imaging of the brain and circle of Willis, to exclude a compressive or inflammatory lesion, and had a temporal artery biopsy showing granulomatous arteritis. Results: Four patients (aged 63–82) were identified and included. One patient had a complete third nerve palsy with pupil involvement, whereas the other 3 had third nerve palsies without pupil involvement. Three patients had ipsilateral periorbital/brow pain, and the other patient had temporal headache. Two patients reported no systemic symptoms of GCA but had elevated inflammatory markers. One patient had normal inflammatory markers but reported systemic symptoms of GCA. All patients had rapid improvement in symptoms and signs after high-dose oral prednisone was started with all showing complete recovery within weeks. Conclusions: GCA can rarely present with acute painful third nerve palsy, mimicking the presentation of a microvascular cause. The third nerve palsy often improves rapidly after steroid treatment is started. The presence of GCA symptoms or elevated inflammatory markers in a patient older than 50 years with an acute third nerve palsy should prompt initiation of high-dose steroid treatment and temporal artery biopsy.

Optic Neuropathy Due to Biotinidase Deficiency in a 19-Year-Old Man

Author Contributions: Dr Liu had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Liu, Sullivan. Acquisition of data: Liu. Analysis and interpretation of data: All authors. Drafting of the manuscript: Liu, Sullivan. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: Liu, Sullivan. Obtained funding: Liu, Sullivan. Administrative, technical, or material support: Kam, Ding. Study supervision: Liu, Sullivan.