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Dive into the research topics where Thomas H. Pettit is active.

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Featured researches published by Thomas H. Pettit.


Ophthalmology | 1983

Acquired Immune Deficiency Syndrome: Ocular Manifestations

Gary N. Holland; Jay S. Pepose; Thomas H. Pettit; Michael S. Gottlieb; Robert D. Yee; Robert Y. Foos

The acquired immune deficiency syndrome (AIDS) is a recently described disorder of cellular immunity in homosexuals, intravenous drug abusers, and Haitians. Manifestations include Kaposis sarcoma, Pneumocystis carinii pneumonia, and other opportunistic infections. Ophthalmic and autopsy examinations of 30 patients at UCLA revealed frequent ocular abnormalities. Findings included cotton-wool spots (16 patients), cytomegalovirus retinitis (eight patients), conjunctivitis and keratitis (four patients), conjunctival Kaposis sarcoma (three patients), Mycobacterium avium intracellulare choroidal granulomas (one patient), and retinal periphlebitis (one patient). We feel that the presence of cotton-wool spots in patients with this syndrome indicates a poor prognosis. Immunologic and electronmicroscopic studies of cotton-wool spots revealed no infectious agents or immunoglobulin deposition. Cytomegalovirus retinitis always was associated with a fatal outcome. The retinitis was characterized by an acute inflammatory reaction in 50% of patients. Ophthalmologists should be aware of the syndrome and its ocular manifestations.


American Journal of Ophthalmology | 1977

Fungal Endophthalmitis Following Intraocular Lens Implantation

Marjorie A. Mosier; Benjamin Lusk; Thomas H. Pettit; Dexter H. Howard; Judith Rhodes

Endophthalmitis developed in a 61-year-pld man after an intraocular lens implantation. A whitish opacity developed, visual acuity decreased to light perception, and we enucleated the eye. Paecilomyces lilacinus (Thom) Samson, a saphrophyte that has contaminated laboratory solutions, was cultured.


American Journal of Ophthalmology | 1984

Corneal Ulcers Associated with Extended-Wear Soft Contact Lenses

Barry A. Weissman; Bartly J. Mondino; Thomas H. Pettit; John Hofbauer

We treated nine myopic and nine aphakic eyes in patients who developed corneal ulcers while wearing extended-wear soft contact lenses. Bacteria were recovered from the corneal ulcers of 13 of 18 patients with Pseudomonas aeruginosa being the pathogen most frequently isolated. Chemical disinfection was used by seven of the nine patients with myopia and eight of the nine with aphakia. Two of nine patients in the myopic group had visual loss to 20/200 and hand movements; five of nine patients in the aphakic group had visual loss to 20/50 or worse. Invasion of the corneal stroma by bacteria may occur after breakdown of the epithelial barrier by contact lens manipulation or after chronic overnight anoxic stress. Thus, the use of soft contact lenses on an extended-wear basis may be complicated by the development of corneal ulcers. Both aphakic and myopic eyes are at risk.


Ophthalmology | 1992

Results of Inpatient and Outpatient Cataract Surgery: A Historical Cohort Comparison

Gary N. Holland; David T. Earl; Noel C. Wheeler; Bradley R. Straatsma; Thomas H. Pettit; Robert S. Hepler; Robert E. Christensen; Robert K. Oye

PURPOSE The transition from inpatient to outpatient cataract surgery during the last decade was not accompanied by prospective investigation of its effect on visual outcomes or surgical complications. The authors performed this study to assess the impact of this transition on surgical results. METHODS The authors reviewed 600 extracapsular cataract extractions performed by 4 experienced ophthalmic surgeons during a 36-month period; in 300 cases, patients were hospitalized after surgery (inpatient group), and, in 300 cases, patients were never hospitalized (outpatient group). The same surgical techniques were used in all cases. Visual outcome and rates for operative and postoperative complications were compared. RESULTS There were no statistically significant differences between the inpatient and outpatient groups for visual acuity. Excluding patients with pre-existing nonlenticular ocular disease, a best-corrected visual acuity of 20/40 or better was achieved in 93.1% of inpatient cases and in 97.2% of outpatient cases 6 months after surgery. Postoperative, clinically apparent cystoid macular edema was more common in the inpatient group (P = 0.03); however, after exclusion of patients with diabetes, hypertension, age younger than 65 years, and eyes with pre-existing nonlenticular disease, there was no statistically significant difference between groups. No significant differences in rates for other operative and postoperative complications were identified, including wound dehiscence, unplanned postoperative filtering blebs, infectious endophthalmitis, retinal detachment, persistent iridocyclitis, glaucoma, and corneal edema. CONCLUSION This study does not demonstrate that the transition to outpatient cataract extractions has had an adverse effect on surgical outcomes.


American Journal of Ophthalmology | 1980

Leukemic Iris Infiltration

Kamal A. Zakka; Robert D. Yee; Norman Shorr; George S. Smith; Thomas H. Pettit; Robert Y. Foos

A 7-year-old boy with acute lymphocytic leukemia developed iris infiltration, blood-streaked hypopyon, and high intraocular pressure. A diagnostic anterior chamber paracentesis was performed, which provided a cytologic diagnosis. The aspirate was studied by both the millipore filter technique with Papanicolaou stain and a dried smear using the Wrights stain. Wrights stain provided more distinct cellular details. Irradiation of the anterior segment resulted in clearing of leukemic iris infiltration, hypopyon, and glaucoma.


Optometry and Vision Science | 1989

Four Cases of Keratoconus and Posterior Polymorphous Corneal Dystrophy

Barry A. Weissman; Matthew Ehrlich; Jeremy E. Levenson; Thomas H. Pettit

We examined four young men with keratoconus and posterior polymorphous corneal dystrophy. All four patients showed central corneal steepening and irregularity, and large areas of irregular polymorphous opacification at the level of Descemets membrane (in at least one cornea of each patient), which are consistent with posterior polymorphous dystrophy.


Ophthalmic surgery | 1985

Neodymium:YAG Laser Posterior Capsulotomy: The First 100 Cases at UCLA

Kathryn M. Gardner; Bradley R. Straatsma; Thomas H. Pettit

Initial anatomic success was reported in 97 of the first 100 neodymium: YAG laser posterior capsulotomies performed at the Jules Stein Eye Institute. Visual acuity improved in 90 patients, was unchanged in five, and decreased in five. In the five patients with decreased visual acuity after posterior capsulotomy, the decrease was unrelated to capsulotomy and caused by progression of preexisting retinal disease. Our experience suggests that attention to patient evaluation and surgical technique can help minimize complications and assure best results.


Ophthalmology | 1981

UCLA Clinical Trial of Radial Keratotomy

Kenneth J. Hoffer; John J. Darin; Thomas H. Pettit; John D. Hofbauer; Richard Elander; Jeremy E. Levenson

A clinical trail of radial keratotomy ws begun under a strict research protocol at the Jules Stein Eye Institute in November 1979. The results for the first 52 eyes undergoing radial keratotomy are reported three months after surgery. Preoperatively uncorrected visual acuity was less than 20/200 in all 52 eyes. and postoperative visual acuity was less than 20/200 in 11 eyes (21%). Three months postoperatively, uncorrected visual acuity was 20/40 or better in 27 eyes (52%) and 20/20 or better in 13 eyes (25%). Postoperatively the best-corrected visual acuity decreased in 10 eyes (20%), but maximum decrease in any eye was one line of snellen letters. Preoperatively mean refractive error was -4.9 (/+-2.2) diopters, and postoperatively the mean decrease in myopia was 3.4 (/+-2.2) diopters. Postoperatively 13 eyes (25%) had a hyperopic refractive error of +0.25 to +3.25 diopters, but all of these eyes were able to accommodate and obtain 20/20 visual acuity without glasses. Postoperatively there was no statistically significant change in axial length, anterior chamber depth, or scleral rigidity, but there was a mean corneal endothelial cell loss of 10% (P = 0.0002). Decrease in myopia achieved by radial keratotomy did not correlate with the steepness of corneal curvature, corneal diameter, or scleral rigidity. Three months after surgery, significant symptoms of glare were present in 10 eyes (20%0, and annoying variable visual acuity was noted in five eyes (10%).


Annals of Internal Medicine | 1985

Aging-Related Cataract: Laboratory Investigation and Clinical Management

Bradley R. Straatsma; Robert Y. Foos; Joseph Horwitz; Kathryn M. Gardner; Thomas H. Pettit

Cataract disrupts the crystalline lens, a transparent, elastic, avascular, biconvex structure composed of a capsule, lens epithelium, and lens fiber cells. Many factors contribute to the progression of lens opacity, but aging is most frequently associated with cataract. As aging-related cataract develops, many biochemical and biophysical changes occur, most notably a marked increase in the insolubilization of the crystallin and extensive oxidation damage to many of the lens constituents. Cataract management should include ophthalmologic history and examination, medical evaluation, optical correction, control of ocular and systemic disease that may contribute to cataract, discontinuation of cataractogenic drugs, and periodic reexamination. Surgery is indicated when cataract is associated with vision decrease interfering with activities important to the patient, intraocular inflammation or glaucoma, or interference with management of posterior segment disease. More than 600 000 cataract operations are done in the United States each year; in 1982 an estimated 496 000 cataract operations were combined with intraocular lens implantation.


Ophthalmic Surgery and Lasers | 1983

Maintenance of Mydriasis with Epinephrine During Cataract Surgery

R. Michael Duffin; Thomas H. Pettit; Bradley R. Straatsma

The pupillary response to various doses of intraocular epinephrine (0.1 ml of 1:16,000, 1:32,000, 1:64,000, 1:80,000, or 1:96,000) was studied in 55 consecutive patients during extracapsular cataract surgery. The 1:16,000 epinephrine concentration provided a mean 0.74 mm increase in pupil diameter (range 0.0 to 1.7 mm) when administered to re-dilate the pupil after nucleus expression. The mean increase in pupil area with 1:16,000 epinephrine was 27% which greatly facilitated removal of lens cortex in most cases. However, 25% of all pupils failed to dilate with epinephrine 1:16,000. The other concentrations provided essentially the same mydriasis as the 1:16,000 concentration. Pupils smaller than 6 mm dilated more easily than pupils larger than 6 mm. Iris color, age, or sex had no significant effect on the mydriatic response. It is concluded that an extremely dilute concentration of epinephrine (i.e., 1:96,000 or less) may be effective in maintaining mydriasis during cataract surgery.

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Robert Y. Foos

Jules Stein Eye Institute

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Gary N. Holland

Jules Stein Eye Institute

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Robert D. Yee

University of California

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