Charcot-Marie-Tooth disease associated with recurrent optic neuritis.

The factors precipitating central nervous system (CNS) demyelination, including optic neuritis, remain largely unknown but are likely to represent a complex interplay between the patient's environment and their genetic background. We report the development of sequential demyelinating optic neuritis in a patient with genetically confirmed Charcot-Marie-Tooth disease type 1A, a hereditary neuropathy. This neuropathy is characterized by duplication of peripheral myelin protein 22 (PMP22), which results in structurally abnormal peripheral myelin. By characterizing peripheral T-cell responses in this patient to a panel of myelin epitopes expressed in the CNS we describe an immunological process which indicates that overexpression of PMP22 may be causative and account for this association.

Effect of the angle of the operating microscope light beam on visual recovery after phacoemulsification: Randomized trial.

PURPOSE: To evaluate differences in visual recovery after phacoemulsification with direct or tilted surgical microscope illumination using a macular photostress test. SETTING: Western Eye Hospital, Imperial College Health Care National Health Service Trust, London, United Kingdom. METHODS: This randomized double-masked controlled trial enrolled patients presenting to a daycare unit for single-eye cataract surgery. Inclusion criteria were no ocular pathology other than cataract, corneal keratometric astigmatism less than 1.50 diopters, intended target of emmetropia in the operated eye, and cataract grade 1 to 3 (Lens Opacification Classification System II). Exclusion criteria were an abnormal preoperative photostress test. Patients were randomized to have phacoemulsification with the operating microscope angled 15 degrees nasal to the fovea (study group) or with the operating microscope directly overhead around the optic disc region (control group). The same surgeon performed all phacoemulsification procedures using a standardized technique and topical anesthesia. Outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuity 10 minutes and 60 minutes postoperatively. RESULTS: In the 30 patients evaluated, the mean UDVA 10 minutes postoperatively was 0.40 logMAR +/- 0.26 (SD) in the study group and 0.72 +/- 0.36 logMAR in the control group (P<.01). The mean CDVA was 0.18 +/- 0.26 logMAR and 0.44 +/- 0.30 logMAR, respectively (P = .016). There was no significant between-group difference in acuity at 60 minutes. CONCLUSION: Tilting the microscope beam away from the fovea resulted in faster visual recovery and less macular photic stress. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.