William L. Hutton

Factors Influencing Final Visual Results in Severely Injured Eyes

We reviewed 194 consecutive eyes treated by pars plana vitrectomy for severe injury with posterior segment involvement. By using multivariate analysis, we determined which of a large number of clinical, ultrasonographic, and electrophysiologic factors influenced or predicted postoperative visual acuity. Additionally, the effects of the timing of vitrectomy on final vision and the usefulness of prophylactic scleral buckling were analyzed. We found that although clinical data have predictive value, it is electrophysiological information, specifically the visual-evoked potential, which most accurately predicts the postoperative vision of an injured eye. We could not demonstrate a significant effect of the timing of surgery on the final visual result but could determine that prophylactic scleral buckling clearly reduces the rate of delayed retinal detachments.

Retained Intravitreal Lens Fragments after Cataract Surgery

PURPOSE The purpose of this study is to review the possible benefits and complications of vitrectomy for retained lens fragments after cataract surgery. METHODS The authors reviewed the charts of 65 patients referred over a 12-year period for retained lens fragments after cataract surgery. Of these, 56 underwent vitrectomy and 9 were followed. Of these 56 eyes, 29 (52%) had received an intraocular lens (IOL) at the time of cataract surgery. RESULTS Resulting complications from retained lens material included glaucoma (52%), corneal edema (46%), uveitis (56%), and decreased vision (100%). These sequelae responded equally to vitrectomy in eyes with or without an IOL and irrespective of type of cataract surgery (phacoemulsification or extracapsular cataract extraction). The timing of surgery did not statistically influence the final vision or the incidence of glaucoma. CONCLUSION Removal of retained lens fragments allows rapid visual restoration, enhances resolution of uveitis, and improves control of glaucoma. Insertion of an IOL at the time of cataract surgery in the face of dislocated lens fragments is not contraindicated provided that it could be performed safely.

Visual field defects after macular hole surgery. A new finding.

PURPOSE The purpose of the study is to report the problem of a temporal visual field defect occurring after macular hole surgery. METHODS The authors reviewed the records of 13 patients found to have visual field defects after vitrectomy for macular holes. Fluorescein angiograms (13 patients), optic nerve photographs (13 patients), focal electroretinograms (3 patients), and nerve fiber analyses (8 patients) were performed in patients with visual field defects. RESULTS An absolute, temporal, usually inferior field defect was noted in 13 patients. In eight patients, the defect was detected because of specific reports or retrospective field examination results. Five patients examined in a prospective manner were found to have field defects. No history of abnormal intraocular pressure or direct trauma to the optic nerve or retinal vessels was identified. Four patients showed optic nerve pallor and three had an anomalous-appearing disc. Focal electroretinograms were of similar amplitude in the involved retina compared to corresponding areas in the healthy fellow eye. Nerve fiber analysis showed a reduction in nerve fiber layer thickness correlating to the visual field defect in those eight patients in which this test was used. CONCLUSION A significant temporal field defect may occur in patients after otherwise uncomplicated surgery for macular holes. The cause is unclear; however, reductions in nerve fiber layer thickness from the superior and nasal peripapillary area suggest that acute surgical release of the posterior hyaloid and the use of long-acting intraocular gas may in certain patients result in visual field defects.

Management of surgically dislocated intravitreal lens fragments by pars plana vitrectomy.

We examined 26 eyes (19 of them following phacoemulsification) with surgically dislocated intravitreal lens fragments; 24 eyes were subsequently operated on using pars plana vitrectomy for removal of lens fragments. From this select group of patients we found moderate to severe uveitis, glaucoma, and vitreous opacification present in virtually all cases. Less common complications were retinal detachments (six cases) and bullous keratopathy; the latter problem was found most commonly in eyes subjected to anterior segment maneuvers such as the use of lens loops or vitreous irrigation for removal of the lens material. Pars plana vitrectomy proved an excellent method for removal of lens fragments. A simultaneous two-instrument technique using the Wilson foreign-body forceps and the vitrectomy machine facilitated removal of the denser sclerotic lens fragments. This procedure resulted in resolution of the uveitis and glaucoma with improvement in visual acuity in 20 of the 24 eyes. However, only 10 of the 24 patients operated on obtained 20/40 or better visual acuity. A relatively prompt pars plana vitrectomy in eyes subjected to a minimum of surgical trauma yielded the best visual results.

Cataract Extraction in the Diabetic Eye after Vitrectomy

We examined 289 phakic, diabetic eyes for evidence of cataract formation after a successful vitrectomy. Of 289 eyes, 107 (37%) developed or had significant progression of a cataract over a follow-up period of 16 to 108 months. Postvitrectomy hemorrhage and vitreous lavage were associated with an increased rate of cataract formation. Of the 107 eyes, 33 (31%) subsequently had cataract extraction, with 24 eyes (73%) treated by extracapsular cataract extraction and nine eyes (27%) with intracapsular surgery. A posterior chamber lens was used in 11 of the 24 eyes that underwent extracapsular surgery. Of the 33 eyes, 31 (94%) had improved visual acuity after cataract extraction. Intraoperative and postoperative complications were minimal and did not result in permanent reduction of vision. Intraocular lenses were well tolerated in the 11 patients in whom they were used.

prediction Of Postoperative Vision In Eyes With Severe Trauma

&NA; The single most important factor determining the potential for return of useful vision in severely injured eyes is the magnitude of damage incurred by the macula or optic nerve at the time of injury. Most gravely injured eyes have media opacities that prevent funduscopic examination. In such eyes, the flash visually evoked potential is the single best predictor of postoperative vision. The second most reliable predictor is the bright‐flash electroretinogram. Ultrasonography is an important part of the preoperative assessment of injured eyes with opaque media, but is of less value than electrophysiological testing in predicting postoperative vision in eyes with major trauma.

Retinal Detachment and Pseudophakia

A consecutive series of pseudophakic retinal detachments was statistically compared with a matched group of aphakic retinal detachments. Distribution of breaks, anatomic results, and final visual acuities were tabulated. Success in reattachment was equal in the two groups, but final visual acuities were better in the aphakic group. Emphasis was placed on the intraoperative ophthalmoscopic examination of pseudophakic eyes with compromised peripheral fundus visibility.

Temporary Keratoprosthesis for Combined Penetrating Keratoplasty, Pars Plana Vitrectomy, and Repair of Retinal Detachment

The Landers-Foulks temporary keratoprosthesis was used to combine penetrating keratoplasty, pars plana vitrectomy, and scleral buckling in the management of 13 eyes with opaque cornea and posterior segment abnormalities. In seven cases, trauma precipitated the ocular disease. Complications of cataract surgery resulted in anterior and posterior segment pathology in six cases. The corneal graft was initially clear in all cases. However, corneal edema complicated phthisis bulbi in four cases and followed homograft reaction in two cases. Eight eyes with retinal detachment (RD) preoperatively were successfully reattached. In five eyes, the retina redetached as these eyes became phthisical. Visual function improved in six cases. In general, eyes with a history of trauma had a much poorer outcome than did eyes with anterior and posterior segment problems related to previous cataract surgery.

Diabetic Traction Retinal Detachment: Factors Influencing Final Visual Acuity

A group of eyes with clear media and diabetic traction retinal detachments treated with vitreous surgery were statistically analyzed to identify those parameters that would allow us to improve case selection. The configuration of the retinal detachment proved to be important, with hammock and flat diffuse central detachments having a good prognosis, and highly elevated, atrophic detachments such as table-top and tent-shaped demonstrating a poor prognosis. Eyes with florid diabetic retinopathy did less well than those with more inactive forms of retinopathy. Preretinal membranectomy, although accompanied by an increased rate of iatrogenic retinal tears, has a definite role in the treatment of more complex traction detachments and increases the number of eyes that may benefit from surgery. Eyes with preoperative vision better than 5/200 did significantly better than eyes with poorer preoperative vision.

Pars Plana Vitrectomy for Removal of Intravitreous Cysticercus

Pars plana was used for the removal of an intravitreous cysticercus, with minimal postoperative inflammation and an excellent visual result. This approach avoids lens removal and the visualization provided by the operating microscope allows removal of all vitreous humor particles and debris. The aspirated specimens allowed identification of the Taenia solium cysticercus.