Biomedical subjects

J B Kerrison

Publications and source records attributed to J B Kerrison.

4 recordsLinked to original sources

PubMed1996

A gene for autosomal dominant congenital nystagmus localizes to 6p12.

Congenital nystagmus is an idiopathic disorder characterized by bilateral ocular oscillations usually manifest during infancy. Vision is typically decreased due to slippage of images across the fovea. As such, visual acuity correlates with nystagmus intensity, which is the amplitude and frequency of eye movements at a given position of gaze. X-linked, autosomal dominant, and autosomal recessive pedigrees have been described, but no mapping studies have been published. We recently described a large pedigree with autosomal dominant congenital nystagmus. A genome-wide search resulted in six markers on 6p linked by two-point analysis at theta = 0 (D6S459, D6S452, D6S465, FTHP1, D6S257, D6S430). Haplotype analysis localizes the gene for autosomal dominant congenital motor nystagmus to an 18-cM region between D6S271 and D6S455.

Chromosome Mapping↗

PubMed1996

Visual field loss following vitreous surgery.

OBJECTIVE: To assess possible causes of visual field loss following vitreous surgery. DESIGN: Charts of 8 patients prospectively identified, who developed visual field loss following vitreous surgery, were reviewed to characterize this newly recognized syndrome and assess possible causes. RESULTS: Two patients had preexisting chronic open-angle glaucoma and 1 had ocular hypertension. Indications for surgery included 4 eyes with macular holes, 1 eye with epiretinal membrane, 2 eyes with rhegmatogenous retinal detachment, and 1 eye with retinal detachment and giant retinal tear. All patients received retrobulbar anesthesia. Seven of 8 patients had fluid/gas exchange with installation of long-acting bubbles. In 1 patient with a macular hole, a small hemorrhage was noted along a vessel coming off the nerve superotemporally while attempting to engage the posterior cortical vitreous intraoperatively. This patient developed an inferior visual field defect. No intraocular pressure (IOP) measurements greater than 26 mm Hg were recorded in any eye perioperatively. Visual field defects included 4 eyes with inferotemporal defects, 2 eyes with inferior altitudinal defects, 1 eye with a cecocentral scotoma, and 1 eye with a superonasal defect. Only 1 patient had worsened visual acuity. A relative afferent pupillary defect was observed in 4 eyes and disc pallor in 5 eyes. CONCLUSIONS: Central or peripheral visual field loss can now be recognized as a possible complication of vitreous surgery. In some cases, a relative afferent pupillary defect and optic disc pallor are present, suggesting that the optic nerve is the site of injury. Possible mechanisms include ischemia due to elevated IOP or fluctuations in IOP, optic nerve damage from retrobulbar injection, direct intraoperative mechanical trauma to the optic nerve, indirect injury from vigorous suction near the optic nerve leading to shearing of peripapillary axons or vessels, or a combination of these. Certain optic nerves may be more susceptible to injury because of preexisting compromise from glaucoma or vascular disease.

Adult↗

PubMed1996

Phacoemulsification after retinal detachment surgery.

PURPOSE: Previous studies have documented a 3% to 15.5% risk of retinal redetachment in eyes with prior scleral buckling procedures that later undergo intracapsular or extracapsular cataract extraction. The authors reviewed the records of patients with a history of retinal detachment (RD) surgery and subsequent phacoemulsification to assess the risk of retinal redetachment and the visual outcomes. METHODS: Forty-seven eyes of 44 patients with a history of scleral buckling surgery who subsequently underwent phacoemulsification were identified. Features found before, during, and after surgery were reviewed. RESULTS: No retinal redetachments occurred on a mean follow-up of 2.3 years. Eyes with RD repair were more myopic than fellow eyes (P=<0.001), had longer axial lengths (P=0.001), had steeper keratometry readings (P=0.03), and had larger differences in K readings between principal meridians (P=0.01). Postoperative visual acuity was 20/40 or better in 72.3% of eyes and 20/80 or worse in 6.4% of eyes. Preexisting macular pathology was responsible for poor outcomes. CONCLUSION: The risk of redetachment after phacoemulsification in eyes with previous RD surgery is low. Despite retinal and cataract surgery, these eyes can achieve useful vision.

Adolescent↗

PubMed1994

Retinal pathologic changes in multiple sclerosis.

PURPOSE: To describe the ocular pathologic changes in multiple sclerosis (MS), with attention to its effects on the uveal tract and retinal veins. METHODS: Cases of 26 patients with MS and 3 patients with neuromyelitis optica were reviewed; retinal trypsin digestion was performed on remaining wet tissue for 20 of these patients. Eyes were specifically examined for inflammation of the retinal vessels, uveal tract, retina, optic nerve, and pars plana. Specimens were also examined for atrophy of the optic nerve, ganglion cell, and nerve fiber layers. RESULTS: Atrophy of the nerve fiber and ganglion cell layers was present in 73% of the cases with MS and correlated with optic nerve atrophy; choroiditis was present in 11.5%; bilateral cyclitis without other foci of inflammation was present in 1 case; and retinal phlebitis was present in 20% (most of which were only identified after trypsin digestion). Optic nerve inflammation was present in two of the patients with neuromyelitis optica. CONCLUSION: Uveitis and retinal phlebitis are manifestations of MS. Trypsin digestion with microscopic examination is a sensitive method of testing for phlebitis, which may explain why the frequency found in this series is higher than in others. These lesions are similar to the perivenular cuffing that occurs in the central nervous system in MS.

Adult↗