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J D Gottsch

Publications and source records attributed to J D Gottsch.

At least 55 records · Page 3Linked to original sources
PubMed1992

Light-dependent generation of superoxide from human erythrocytes.

Using the cytochrome c reduction method, we investigated light-dependent erythrocytic superoxide production. After 4 h light and dark exposure of erythrocytes from eight healthy human subjects, an average of 18.6% more superoxide was generated by erythrocytes exposed to light. Pretreatment of erythrocytes with the superoxide dismutase inhibitor N,N-diethyldithiocarbamate increased detection of superoxide while pretreatment with the anion channel blocker 4-acetamido-4'-isothiocyano-2,2'-disulfonic acid stilbene decreased detection. These findings indicate that substantially more spontaneously generated superoxide is produced and escapes from normal erythrocytes at ambient oxygen tensions on exposure to light. This excess generation and escape of superoxide from erythrocytes exposed to light may result in tissue photosensitization, especially in the retina of the eye, where high oxygen tension, blood and chronic light exposure occur simultaneously.

Adult↗
PubMed1991

A population-based evaluation of glaucoma screening: the Baltimore Eye Survey.

The Baltimore Eye Survey was a population-based survey conducted from January 1985 to November 1988 among residents of east Baltimore, Maryland, who were 40 years of age or older. A total of 5,308 black subjects and white subjects received a comprehensive screening examination for glaucoma including tonometry, visual fields, stereoscopic fundus photography, and a detailed medical and ophthalmic history. Based on a definitive examination, a diagnosis of glaucoma of any type was made for 196 persons. Tonometry, cup:disc ratio, and narrowest neuroretinal rim width were evaluated for their ability to correctly classify subjects into diseased or nondiseased states. There were no cutoff values at which these variables provided a reasonable balance of sensitivity and specificity, separately or in combination. Logistic regression models were fit that included demographic and other risk factors. Sensitivities and specificities were calculated for varying cutoff levels on the distribution of predicted probabilities. There was no cutoff for which reasonable sensitivity and specificity were obtained. The authors conclude that the effectiveness of current techniques for glaucoma screening is limited.

Adult↗
PubMed1991

Racial differences in the cause-specific prevalence of blindness in east Baltimore.

BACKGROUND: Bilateral blindness unrelated to simple refractive error is twice as prevalent among blacks as among whites, although the difference narrows among the elderly. The reasons for this race- and age-related pattern are uncertain. METHODS AND RESULTS: A randomly selected, stratified, multistage cluster sample of 2395 blacks and 2913 whites 40 years of age and older in East Baltimore underwent detailed ophthalmic examinations by a single team. We identified 64 subjects who were blind in both eyes. The leading causes of blindness were unoperated senile cataract (accounting for blindness in 27 of the total of 128 eyes), primary open-angle glaucoma (17 eyes), and age-related macular degeneration (16 eyes). Together, these three disorders accounted for 47 percent of all blindness in this sample. Unoperated cataract accounted for 27 percent of all blindness among blacks, among whom it was four times more common than among whites; whites were almost 50 percent more likely than blacks to have undergone cataract extraction before the age of 80 (P less than 0.002). Primary open-angle glaucoma accounted for 19 percent of all blindness among blacks; it was six times as frequent among blacks as among whites and began 10 years earlier, on average. By contrast, age-related macular degeneration resulting in blindness was limited to whites, among whom it was the leading cause of blindness (prevalence, 2.7 per 1000; 95 percent confidence interval, 1.2 to 5.4); it affected 3 percent of all white subjects 80 years of age or older. CONCLUSIONS: The pattern of blindness in urban Baltimore appears to be different among blacks and whites. Whites are far more likely to have age-related macular degeneration, and blacks to have primary open-angle glaucoma. The high rate of unoperated cataracts among younger blacks and among elderly subjects of both races suggests that health services are underused. Half of all blindness in this urban population is probably preventable or reversible.

Adult↗
PubMed1991

Light-dependent spin trapping of hydroxyl radical from human erythrocytes.

The generation of reactive oxygen species from human erythrocytes has previously been demonstrated. Furthermore, erythrocytic protoporphyrin IX has been shown to generate superoxide and singlet oxygen when exposed to light. These findings suggest that a component of erythrocytic reactive oxygen species production may be light-dependent. By inhibiting erythrocyte superoxide dismutase, catalase, and glutathione peroxidase with N,N-diethyldithiocarbamate or sodium cyanide, we demonstrate the light-dependent generation of hydroxyl radical in human erythrocytes using spin trapping/Electron Spin Resonance spectroscopy. This finding may be significant in tissues where blood is exposed to light, such as in the eye.

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗
PubMed1991

Infectious keratitis and cyanoacrylate adhesive.

We studied three patients with infectious keratitis that occurred after cyanoacrylate gluing despite prophylactic antibiotic therapy. Two patients developed culture-positive bacterial ulcers, one caused by a methicillin-resistant Staphylococcus aureus and the other by Haemophilus influenzae. The third patient developed a fungal keratitis. Two patients required penetrating keratoplasty. Each infection and perforation was concealed by the opaqueness of the glue. The pain of the infectious ulcers may have been obscured by the ocular surface irritation and drying induced by glue. Tissue toxicity, microbial colonization, use of bandage lenses, and long-term broad-spectrum antibiotics may precipitate glue-related corneal infections. Masking of underlying infection and the development of resistant organisms should be considered when using this mode of therapy.

Adolescent↗
PubMed1991

Relationship between intraocular pressure and primary open angle glaucoma among white and black Americans. The Baltimore Eye Survey.

A detailed ocular examination, including perimetry, was conducted on 5308 black and white subjects aged 40 years and older in a population-based prevalence survey in east Baltimore, Md. Repeated, detailed examinations were carried out on selected subjects. Roughly half of all subjects with optic nerve damage from primary open angle glaucoma, regardless of race, were unaware that they had the condition. The average intraocular pressure (IOP) among black patients with glaucoma who were receiving treatment was virtually identical to that in those black patients who were not receiving treatment (median IOP, 20 mm Hg); treated eyes of white patients had a lower IOP than those eyes of white patients who were not receiving treatment (mean [+/- SD] IOP, 18.69 +/- 3.23 mm Hg vs 24.15 +/- 5.23 mm Hg; P less than .001). The risk of glaucomatous optic nerve damage increased with the height of the screening IOP, particularly at levels of 22 to 29 and 30 mm Hg and above (relative rate compared with IOP of 15 mm Hg or lower, 12.8 and 40.1 mm Hg, respectively). More than half of all glaucomatous eyes had a screening IOP below 21 mm Hg, whether these eyes were receiving treatment or not. The IOP in glaucomatous eyes tended to rise on follow-up, in contrast with nonglaucomatous eyes in which the IOP was as likely to rise as to fall. Results confirmed that IOP is an important factor in glaucoma, but did not support the traditional distinction between "normal" and "elevated" pressure, nor its corollaries, "low-tension" glaucoma and "high-tension" glaucoma.

Black People↗
PubMed1991

Excimer laser ablative treatment of microbial keratitis.

The 193-nm excimer laser was used to ablate experimental septate fungal (Fusarium) and an atypical mycobacterial (Mycobacterium fortuitum) keratitis in an animal model. The infections were allowed to proceed for 24 and 72 hours. After incubation, ablation with a 193-nm excimer laser with 5.0-mm treatment zones was performed until all suppurative areas were treated. The corneas were excised, halved, homogenized, and plated. All cultures were negative in the 24-hour group. However, in those corneas in which the infections were allowed to proceed to 72 hours, post-treatment cultures were positive for both organisms. Histopathologic examination confirmed that 24-hour infections had been eradicated and that 72-hour infections had organisms present. Three of the eight eyes in the M. fortuitum group perforated during treatment, even though the treatment depth by computer preselection was only 150 microns. Excimer laser photoablation may be a useful technique to eradicate early, localized microbial infections. However, it is apparent that advanced infections with deep stromal involvement and suppuration cannot be eradicated using this technique. Because corneas may be perforated inadvertently during treatment, excimer laser treatment of infectious keratitis should be approached with caution and used for superficial and well circumscribed lesions.

Animals↗
PubMed1991

Natural history of corneal astigmatism after cataract surgery.

Little information on the natural course of corneal astigmatism following cataract surgery exists. We report a prospective, computerized analysis of postoperative astigmatism, based on keratometry measurements, of 137 cases of extracapsular cataract extraction with intraocular lens implantation performed by one surgeon. No sutures were cut postoperatively. Surgery induced 1.44 diopters (D) of with-the-rule astigmatism at one month, which declined at a rate of 0.77 D and 0.35 D per month for the next two months, respectively, with a more gradual decline thereafter. The mean surgically induced astigmatism at the last postoperative visit ranged from 0.29 D at six months (minimum follow-up) to 1.23 D at 48 months; both were against-the-rule. Mean follow-up was 28.92 months. These findings may be technique specific and suggest that (1) corneal curvature continues to change slowly even two to four years postoperatively; (2) most patients develop against-the-rule astigmatism, thus more with-the-rule astigmatism is desirable in the early postoperative period; (3) selective suture removal is necessary only when significantly more than 3.00 D of surgically induced with-the-rule astigmatism is present.

Aged↗
PubMed1990

A systematic approach to the diagnosis and treatment of chronic conjunctivitis.

In 58 patients with chronic conjunctivitis of greater than two weeks' duration, examination included obtaining an ocular and general medical history and performing a complete ophthalmic examination of the external eye. Conjunctival smears were obtained for Gram and Giemsa staining, direct immunofluorescent monoclonal antibody staining for Chlamydia trachomatis and herpes simplex virus, and chlamydial culture. Cultures for bacteria and viruses were obtained in 33 patients. The cause of the chronic conjunctivitis based on clinical and laboratory criteria was established in 40 of 58 (69%) patients: chlamydia, 11 (19%); virus, eight (14%); irritant, six (10%); allergen, four (7%); contact lens, four (7%); bacteria, four (7%); acne rosacea, two (3%); and floppy eyelid syndrome, one (2%). In 18 of 58 (31%) patients, no specific cause was detected. We recommend a systematic approach in the investigation of chronic conjunctivitis. Direct immunofluorescent monoclonal antibody staining is an effective and rapid technique for detecting chronic chlamydial conjunctivitis.

Adult↗
PubMed1990

Therapeutic contact lenses.

Therapeutic contact lenses are useful in a variety of ocular surface disorders. Their efficacy was evaluated in 40 consecutive patients presenting for therapeutic contact lens fitting for pain due to depressed surface disorders (14 patients), raised surface disorders (11 patients), corneal decompensation (7 patients), trauma (5 patients), and disorders of corneal wetting (3 patients). The therapeutic contact lens was successfully fit and worn, with achievement of the therapeutic objective in 37 of the 40 patients. Corneal wetting disorders and corneal decompensation require only intermediate-term contact lens wear. Thus, therapeutic contact lenses are usually effective for relief of pain due to corneal surface disorders.

Adolescent↗
PubMed1990

Hyphema: diagnosis and management.

The management of traumatic hyphema has been controversial for many years. Treatments designed to prevent secondary hemorrhage have been proposed in the literature, then later abandoned when prospective studies failed to support them. In the last several years, published studies have demonstrated the efficacy of antifibrinolytic agents in the prevention of secondary hemorrhages. These studies have left unanswered some questions, however, such as whether antifibrinolytics are as effective in children as adults, in white patients as black, and in patients with normal hemoglobin as well as those with sickle cell hemoglobinopathies. The successful treatment of patients with hyphemas hinges on identification of risk factors, proper medical management and prompt surgical intervention when medical therapy fails.

Eye Hemorrhage↗
PubMed1990

Visual disabilities related to intraocular lens design.

Intraocular lens implantation after cataract extraction has become a common practice in the United States. However, unwanted optical images can correct an otherwise successful surgery into one that causes patient dissatisfaction. Refinements in manufacturing design and finishing have greatly improved the quality of present day intraocular lenses, but there is continued interest in simulating the optics of the human crystalline lens. We will discuss the optical requirements of intraocular lenses and how these are influenced by optic design and dimension, and spectral transmission characteristics.

Humans↗
PubMed1990

Hematogenous photosensitization. A mechanism for the development of age-related macular degeneration.

Age-related macular degeneration (ARMD) is one of the leading causes of severe visual loss in the United States. Numerous risk factors have been investigated, but the pathogenesis of ARMD has remained elusive. The authors propose that ARMD develops as a direct result of photosensitization of the vascular endothelium of the choriocapillaris, Bruch's membrane, and the retinal pigment epithelium (RPE) by superoxide anion and singlet oxygen generated by photoactive compounds in blood. Using electron-spin resonance spectrometry, the free-radical trap, 5,5-dimethyl-1-pyrroline-N-oxide, and the singlet-oxygen trap, 2-(9,10-dimethoxyanthracentyl)-t-butylhydroxylamine, the authors demonstrate that the photoactive compound, protoporphyrin IX (PP IX), a naturally occurring precursor molecule of hemoglobin found in erythrocytes and plasma, generates superoxide anion and singlet oxygen. The amount of reactive-oxygen species produced by this system is dependent on the concentration of PP IX and the intensity and wavelength of the light delivered. Furthermore, the production of these photooxidants is significantly reduced by filtering the excitatory wavelengths of PP IX. These photogenerated oxidants could damage the vascular endothelium of the choriocapillaris, Bruch's membrane, and the RPE, necessitating a reparative process. This could result in features characteristically seen in ARMD such as a thickened Bruch's membrane, RPE atrophy, and hyperplasia. Prevention of phototoxic damage by this mechanism could involve enhancing protective enzymes, increasing scavenger substances, or supplying appropriate filters to eliminate the exciting wavelengths of light.

Aging↗
PubMed1989

Posterior chamber intraocular lens implantation in the absence of capsular support.

To avoid the complications associated with anterior chamber intraocular lenses (IOLs), we have developed a technique for the implantation of a posterior chamber IOL in the absence of capsular support. The IOL is secured in the ciliary sulcus by suturing the haptics to the sclera at the ciliary sulcus inferiorly and to the sclera or iris superiorly. We have used this technique for secondary IOL implantation in 16 contact lens-intolerant patients with aphakia with a mean follow-up of 9 months (range, 5 to 20 months) and in eight eyes at the time of IOL removal. All eyes with secondary implants had equal or improved vision postoperatively; none developed persistent angiographic cystoid macular edema. In the 8 patients with IOL exchange, visual acuity improved in five eyes, remained the same in two, and decreased two lines in one. Suturing of an IOL in the ciliary sulcus has enabled us to use a posterior chamber IOL in eyes without a posterior capsule when secondary IOL implantation or IOL exchange is indicated. Secondary posterior chamber IOL implantation is recommended only when satisfactory vision cannot be achieved with glasses or contact lenses, and further follow-up is needed before this procedure can be widely recommended.

Aged↗