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Biomedical subjects

R K Parrish

Publications and source records attributed to R K Parrish.

At least 19 recordsLinked to original sources
PubMed2000

Combined pars plana vitrectomy and glaucoma drainage implant placement for refractory glaucoma.

PURPOSE: To report visual acuity and intraocular pressure outcomes among patients who have undergone combined pars plana vitrectomy and placement of a glaucoma drainage implant. METHODS: The medical records of all patients who underwent combined pars plana vitrectomy and placement of a glaucoma drainage implant at the Bascom Palmer Eye Institute by one of the authors between January 1, 1990, and February 28, 1998, were reviewed. Forty patients (40 eyes) were identified, including 14 patients with neovascular glaucoma secondary to proliferative diabetic retinopathy or central retinal vein occlusion, 15 patients with other posterior segment disease, seven patients with secondary angle-closure glaucoma, and four patients with aphakia with ruptured anterior hyaloid face. Main outcome measures included visual acuity and intraocular pressure at 1 year postoperatively. RESULTS: At 1 year postoperatively, 31 (77.5%) of 40 patients had stable or improved visual acuity; three eyes (7. 5%) had a final visual acuity of no light perception and three additional eyes (7.5%) were enucleated (because of chronic pain in two eyes and endophthalmitis in one eye). Mean preoperative intraocular pressure was 34 mm Hg and the median number of preoperative antiglaucoma medications was two. At 1 year postoperatively, mean intraocular pressure was 13 mm Hg and the median number of antiglaucoma medications was zero. Twenty-two patients (55.0%) achieved an intraocular pressure greater than 5 mm Hg and less than or equal to 21 mm Hg without antiglaucoma medication, and an additional seven patients (17.5%) achieved this level of intraocular pressure control with medication. Only one patient (2.5%) underwent further glaucoma surgery for uncontrolled intraocular pressure. CONCLUSIONS: Although combined pars plana vitrectomy and placement of a glaucoma drainage implant is often a successful management option in selected patients with refractory glaucoma, visual outcome may be poor because of severe underlying ocular disease and postoperative complications.

Adult↗
PubMed1999

Surgical revision of glaucoma shunt implants.

BACKGROUND AND OBJECTIVE: To determine the efficacy of surgical revision of glaucoma shunt implants in patients with advanced glaucoma. PATIENTS AND METHODS: The records of 13 patients who underwent revision of their shunt implants were retrospectively reviewed. RESULTS: Surgical success was achieved in: 3 of 3 patients (100%) with drainage tube malposition or extrusion; 1 of 6 patients (17%) with occlusion of the intracameral portion of the drainage tube; and 1 of 4 patients (25%) with elevated intraocular pressure secondary to fibrous capsule formation over the implant. CONCLUSIONS: Surgical revision of glaucoma shunt implants is a useful procedure in patients who develop tube malposition or extrusion. Surgical revision is much less effective in patients with tube occlusion or fibrous capsule formation. Failure of the shunts due to recurrent fibrosis is commonly observed.

Adolescent↗
PubMed1998

Complications of Baerveldt glaucoma drainage implants.

OBJECTIVES: To report the incidence and identify risk factors of postoperative complications after Baerveldt glaucoma drainage implantation. METHODS: A retrospective review of the medical records of all patients at the Bascom Palmer Eye Institute, Miami, Fla, who underwent placement of a Baerveldt glaucoma drainage implant from October 1, 1992, through October 31, 1996, to determine demographic characteristics, preoperative and postoperative intraocular pressures, and complications. Variables were analyzed using the Student t test and Fisher exact test to determine the association between delayed postoperative suprachoroidal hemorrhage and various potential risk factors. RESULTS: A total of 107 eyes of 103 patients were identified. Suprachoroidal hemorrhage occurred in 4 eyes (4%), with onset ranging from 3 to 33 days after implantation. Two eyes (2%) had choroidal effusions requiring surgical drainage, and 20 eyes (19%) had low choroidal effusions requiring only close observation. Tube blockage was observed in 5 eyes (5%). Four eyes (4%) had aqueous misdirection, 2 eyes (2%) had corneal decompensation, and 1 eye (1%) each had endophthalmitis, tube migration, corneal ulcer, hyphema, and implant migration. Patients who were older (P=.04) or had postoperative choroidal effusions (P=.03), low intraocular pressure immediately after the tube opened (P=.03), hypertension (P= .08), or atherosclerosis (P=.09) were more likely to develop suprachoroidal hemorrhage. CONCLUSIONS: A lower incidence of serious postoperative complications was observed in Baerveldt implantations in this study when compared with a recent report. Risk factors for serious complications were similar to trabeculectomy.

Adolescent↗
PubMed1998

The cupped disc. Who needs neuroimaging?

OBJECTIVE: To determine the incidence of positive neuroradiologic studies in consecutive patients with glaucoma associated with normal intraocular pressure and to compare the psychophysical and clinical characteristics of these eyes with eyes with disc cupping associated with intracranial masses. DESIGN: Retrospective case-controlled study. PARTICIPANTS: Fifty-two eyes of 29 patients with glaucoma associated with normal intraocular pressure and 44 eyes of 28 control patients with compressive lesions were reviewed. INTERVENTION: The medical records of consecutive glaucoma patients with normal intraocular pressure who underwent brain magnetic resonance imaging or computed tomography scanning as part of a diagnostic evaluation between January 1, 1985, and July 1, 1995, were reviewed. A masked reading of optic nerve photographs and visual fields was performed by one observer. A similar analysis was performed on a control group of consecutive patients with nonglaucomatous optic nerve cupping with known intracranial mass lesions. MAIN OUTCOME MEASURES: The neuroradiologic findings, clinical characteristics, optic nerve head appearance, and patterns of visual field loss were compared between groups. RESULTS: None of the patients diagnosed with glaucoma had neuroradiologic evidence of a mass lesion involving the anterior visual pathway. Compared to control subjects, patients with glaucoma were older (P = 0.0001), had better visual acuity (P = 0.002), greater vertical loss of neuroretinal rim tissue (P = 0.0001), more frequent optic disc hemorrhages (P = 0.01), less neuroretinal rim pallor (P = 0.0001), and more nerve fiber bundle visual field defects aligned at the horizontal midline (P = 0.0001). Visual acuity less than 20/40, vertically aligned visual field defects, optic nerve pallor in excess of cupping, and age younger than 50 years were 77%, 81%, 90%, and 93% specific for nonglaucomatous cupping associated with compressive lesions, respectively. CONCLUSIONS: Anterior visual pathway compression is an uncommon finding in the neuroradiologic evaluation of patients with a presumptive diagnosis of normal-tension glaucoma. Younger age, lower levels of visual acuity, vertically aligned visual field defects, and neuroretinal rim pallor may increase the likelihood of identifying an intracranial mass lesion.

Adolescent↗
PubMed1998

Trabeculectomy function after cataract extraction.

OBJECTIVE: To examine the effect of cataract extraction (CE) after trabeculectomy on intraocular pressure (IOP) control. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: A total of 115 consecutive patients who underwent extracapsular CE (N = 58) or phacoemulsification (N = 57) with intraocular lens (IOL) placement after trabeculectomy were studied. INTERVENTION: Cataract extraction with IOL after trabeculectomy was performed. MAIN OUTCOME MEASURES: Preoperative, intraoperative, and postoperative factors were evaluated for association with loss of IOP control requiring additional medications, bleb needling, or further glaucoma surgery, using Kaplan-Meier survival analysis and Cox multivariate proportional hazards survival regression. RESULTS: After mean postoperative follow-up of 21.1 +/- 14.3 months, additional glaucoma medication or needling of the filtering bleb to maintain IOP control was required in 35 eyes (30.4%) and was significantly associated with intraoperative iris manipulation and early postoperative peak IOP greater than 25 mmHg. Additional glaucoma surgery was eventually required in 11 eyes (9.6%) and was significantly associated with age of 50 years or younger, preoperative IOP greater than 10 mmHg, and early postoperative peak IOP greater than 25 mmHg. The cumulative proportion of patients who did not require reoperation for glaucoma was 93% and 90% at 1 and 2 years, respectively. The mean IOP at last visit had increased 1.6 mmHg above the pre-CE level and did not vary significantly after the first postoperative month. The median interval from CE to the addition of glaucoma medication or bleb needling was 1.6 months (within 3 months in 20 of 33 eyes) and that from nonsurgical intervention to further glaucoma surgery was 3.6 months (before the 7th postoperative month in 6 of 11 eyes). Of 19 eyes with hypotony (IOP < or = 6 mmHg) before CE, 11 eyes remained hypotonous after CE despite an increase in the mean IOP from 4.6 to 7.5 mmHg. CONCLUSIONS: When CE is performed after trabeculectomy, age of 50 years or younger, preoperative IOP greater than 10 mmHg, intraoperative iris manipulation, and early postoperative IOP greater than 25 mmHg are associated with worsened postoperative IOP control. Most bleb failures occur soon after CE. Resolution of pre-existing hypotony after CE is unpredictable.

Adolescent↗
PubMed1997

Outpatient treatment of bleb infection.

OBJECTIVE: To determine the outcome of outpatient treatment of bleb infection after trabeculectomy. DESIGN: Retrospective review. SETTING: University referral center. PATIENTS: Twelve eyes with bleb infection and without clinical vitreous involvement of 11 patients treated as out-patients from January 1994 to May 1996. INTERVENTIONS: After culture of the bleb surface, treatment consisted of intensive topical antibiotics alone (9 eyes), combined with subconjunctival antibiotic injection (1 eye), oral antibiotics (1 eye), or both (1 eye). Five eyes received topical corticosteroids. MAIN OUTCOME MEASURES: Visual acuity, intraocular pressure, and bleb characteristics. RESULTS: All eyes responded to treatment within 24 to 48 hours, and recovered visual acuity to within 1 line of the preinfection level. Intraocular pressure continued to be controlled after resolution of infection in 11 eyes (92%); 1 bleb failed and medical therapy was resumed. Bleb leaks were noted during treatment of infection in 11 eyes, and 5 eyes (42%) underwent bleb revision. Organisms cultured from the bleb surface included Staphylococcus aureus (8 eyes), Haemophilus influenzae (2 eyes), and Streptococcus (1 eye). Outpatient treatment costs were estimated to be 78% less than inpatient treatment costs, per 24 hours. CONCLUSION: Outpatient treatment of bleb infection was efficacious in this group of patients.

Administration, Topical↗
PubMed1997

Visual function and quality of life among patients with glaucoma.

This study determines the relation between visual field impairment, visual functioning, and global quality of life in patients with glaucoma. Binocular visual field impairment was calculated from simultaneous Esterman visual field testing using the Humphrey automated perimeter. Visual acuity impairment, defined with the American Medical Association's Guides to the Evaluation of Permanent Impairment; visual functioning, measured with the VF-14 and the field test version of the National Eye Institute-Visual Functioning Questionnaire; and global quality of life, assessed with the Medical Outcomes Study 36-Item Short Form Health Survey, were determined in 147 consecutive patients with glaucoma. None of the Medical Outcomes Study 36-Item Short Form Health Survey domains demonstrated more than a weak correlation with visual field impairment. The VF-14 scores were moderately correlated (r = -0.58). Of the National Eye Institute-Visual Functioning Questionnaire scales, peripheral vision (r = -0.60), distance activities (r = -0.56), and vision-specific dependency (r = -0.56) were moderately correlated with visual field impairment; vision-specific social functioning, near activities, vision-specific role difficulties, general vision, vision-specific mental health, color vision, and driving were modestly correlated with visual field impairment (r value between -0.32 and -0.55); visual pain was weakly correlated with visual field impairment; and general health and vision-specific expectations were not notably correlated with visual field impairment. Statistically adjusting for visual acuity weakened the correlations. The Medical Outcomes Study 36-Item Short Form Health Survey indicated that our patients with glaucoma were comparable with previously studied patients without severe systemic medical problems. However, the Medical Outcomes Study 36-Item Short Form Health Survey scores did not correlate with visual field impairment in our study. Based on the moderate correlation between binocular visual field impairment with the VF-14 and the National Eye Institute-Visual Functioning Questionnaire, these questionnaires may be useful among patients with glaucoma.

Adolescent↗
PubMed1997

Delayed-onset endophthalmitis associated with conjunctival filtering blebs.

OBJECTIVE: The purpose of the study is to evaluate the causative organisms, treatment methods, and visual acuity outcomes of patients treated for delayed-onset endophthalmitis associated with conjunctival filtering blebs. METHODS: The medical records of 32 patients with conjunctival filtering bleb-associated endophthalmitis treated at the Bascom Palmer Eye Institute between 1989 and 1995 were reviewed retrospectively. Bleb-associated endophthalmitis was diagnosed at 1 month or more after surgery in all patients. Patients with bleb infections only but without, signs of intraocular infection were excluded from this series. RESULTS: Previous antimetabolite therapy was used in 20 patients, including mitomycin C in 14 and 5-fluorouracil in 6. Streptococcal species were the most frequently cultured organisms occurring in 15 (47%) of 32 eyes. Of the 32 patients, 30 received intraocular antibiotics. The initial treatment included a pars plana vitrectomy in 18 patients and a vitreous tap without vitrectomy in 12 patients. Two of three patients who presented with no light perception vision were treated by evisceration. Overall, 15 (47%) of 32 patients achieved a final visual acuity of 20/400 or better. Of those patients with Streptococcal species cultured from the eye, 6 (40%) of 15 had a visual acuity of 20/400 or better compared to 9 (52%) of 17 in patients with non-Streptococcal species. CONCLUSIONS: Delayed-onset endophthalmitis associated with conjunctival filtering blebs is a current and future concern, especially with increasing use of mitomycin C. The Streptococcal species are a common causative organism. Despite current treatment of these patients, the visual acuity outcomes generally are worse than in patients with acute-onset endophthalmitis after cataract surgery.

Adult↗
PubMed1997

Use of antifibrosis agents and glaucoma drainage devices in the American and Japanese Glaucoma Societies.

PURPOSE: To investigate practice patterns among glaucoma subspecialists in the American Glaucoma Society (AGS) and the Japanese Glaucoma Society (JGS), regarding use of antifibrosis agents and glaucoma drainage devices. METHODS: An anonymous survey incorporating 10 clinical situations was mailed to all AGS and JGS members in December 1995. RESULTS: Half of the AGS (105 of 210), and JGS (25 of 50) members returned surveys. Most respondents (51-87%) preferred trabeculectomy with adjunctive mitomycin for all 10 clinical situations. Mitomycin concentrations varied from 0.1 to 0.8 mg/ml (range of means for 10 situations 0.31-0.39 mg/ml) and intraoperative application times ranged from 5 s to 7 min (range of means for 10 situations 2.5-4.6 min). Preferences for either no antifibrosis agent (up to 39%) or 5-fluorouracil (up to 29%) were highest in primary trabeculectomy. Thirty-seven percent to 64% of AGS members used glaucoma drainage devices, especially after complicated postsurgical glaucomas (after penetrating keratoplasty, scleral buckling, or pars plana vitrectomy) and in neovascular glaucoma, but few JGS members used them. Large differences between university- and private practice-based AGS members were found only in mitomycin use for primary trabeculectomy (33% vs. 52%, respectively; p = 0.07) and for complicated postsurgical glaucomas (46% vs. 70%, respectively; p = 0.03). CONCLUSIONS: Trabeculectomy with mitomycin was the preferred surgical procedure among AGS and JGS members in the clinical situations surveyed. Mitomycin concentration and time of application varied widely. Many respondents used 5-fluorouracil or no antimetabolite in primary trabeculectomy. Glaucoma drainage devices were widely used for complicated glaucomas in the United States.

Chemotherapy, Adjuvant↗
PubMed1996

Genetic heterogeneity in Hispanic families with autosomal dominant juvenile glaucoma.

A gene for autosomal dominant, juvenile-onset, primary open angle glaucoma (GLCIA) has been previously mapped to 1q21-31 in several Caucasian pedigrees. We studied two Hispanic families with this disease to determine if their disease genes also map to this region. Individuals were considered as being affected if they had 1OP > 30 mmHg (without treatment) and glaucomatous optic nerve damage or visual field defects. Persons older than 40 years with intraocular pressures < or = 21 mmHg and no evidence of optic nerve damage or visual field loss were scored as unaffected. Individuals not falling into these two categories were considered unknown. Genomic DNA was extracted from blood samples and subjected to PCR-based microsatellite marker analysis. Computer-based linkage analysis was used to determine if the disease gene mapped to chromosome 1q2I-31. In the family from the Canary Islands, the disease gene was linked to the chromosome 1q2I-31 region previously identified by other researchers. Markers D1S212 and D1S218 produced maximum lod scores of 3.38 and 2.99, respectively. In the family from the Balearic Islands, the disease gene was excluded from this region by genetic linkage analysis. Haplotype analysis also excluded the disease gene from chromosome 1q21-31. Our Hispanic families showed genetic heterogeneity with respect to autosomal dominant, juvenile-onset, primary open angle glaucoma.

Adolescent↗
PubMed1996

Bleb rupture following filtering surgery with mitomycin-C: clinicopathologic correlations.

A 91-year-old woman with a complete rupture of her mitomycin-C filtration bleb associated with eye rubbing while crying was examined. An 18mm soft contact lens was placed preoperatively to re-form the anterior chamber and the patient underwent a conjunctival advancement. Histopathology of the free conjunctival specimen revealed a stratified squamous epithelium with marked attentuation of the subepithelial tissue in the area treated with mitomycin-C. Bleb rupture may be associated with minimal physical trauma following guarded filtration surgery. Successful visual rehabilitation is possible with conjunctival advancement, yet long-term survival of the bleb is poor.

Aged↗
PubMed1996

Airbag-associated injury producing cyclodialysis cleft and ocular hypotony.

Airbags have gained widespread acceptance as devices that reduce the morbidity and mortality associated with motor vehicle accidents. Recent reports of airbag-associated ocular injury suggest that further refinement in airbag technology may be warranted. The authors describe a patient who had a cyclodialysis cleft and ocular hypotony following injury to the eye from an airbag.

Accidents, Traffic↗
PubMed1996

Visual impairment, visual functioning, and quality of life assessments in patients with glaucoma.

BACKGROUND/PURPOSE: To determine the relation between visual impairment, visual functioning, and the global quality of life in patients with glaucoma. METHODS: Visual impairment, defined with the American Medical Association Guides to the Evaluation of Permanent Impairment; visual functioning, measured with the VF-14 and the Field Test Version of the National Eye Institute-Visual Functioning Questionnaire (NEI-VFQ); and the global quality of life, assessed with the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), were determined in 147 consecutive patients with glaucoma. RESULTS: None of the SF-36 domains demonstrated more than a weak correlation with visual impairment. The VF-14 scores were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual field impairment; vision specific social functioning, near activities, vision specific role difficulties, general vision, vision specific mental health, color vision, and driving were modestly correlated; visual pain was weakly correlated; and two were not significantly correlated. Correcting for visual actuity weakened the strength of the correlation coefficients. CONCLUSIONS: The SF-36 is unlikely to be useful in determining visual impairment in patients with glaucoma. Based on the moderate correlation between visual field impairment and the VF-14 score, this questionnaire may be generalizable to patients with glaucoma. Several of the NEI-VFQ scales correlate with visual field impairment scores in patients with a wide range of glaucomatous damage.

Adolescent↗
PubMed1995

Open-angle glaucoma after pars plicata lensectomy and vitrectomy for congenital cataracts.

PURPOSE/METHODS: We examined an infant with familial cataracts in whom bilateral open-angle glaucoma developed shortly after pars plicata lensectomy with anterior vitrectomy. RESULTS/CONCLUSIONS: Some eyes with congenital nuclear cataracts have a predisposition to develop glaucoma after removal of the cataract, which is irrespective of the method chosen to remove the cataract. Careful monitoring of the intraocular pressure is indicated.

Cataract↗
PubMed1995

5-Fluorouracil filtering surgery and neovascular glaucoma. Long-term follow-up of the original pilot study.

BACKGROUND: The long-term efficacy and safety of filtering surgery with 5-fluorouracil (5-FU) in eyes with neovascular glaucoma are unknown. METHODS: Kaplan-Meier survival curve analysis of surgical outcome was performed on all 34 patients (34 eyes) enrolled from May 1982 through April 1986 in the original pilot study of filtering surgery with 5-FU. RESULTS: Success rates at the 1-, 2-, 3-, 4-, and 5-year intervals were 71%, 67%, 61%, 41%, and 28%, respectively. The median filter survival time was 38.7 months (95% confidence interval: 32-45 months). Twelve (35%) of 34 patients lost light perception vision, and phthisis bulbi developed in 8 (24%) of 34 patients. Age of 50 years or younger (P < 0.0001) and type 1 diabetes (P = 0.0004) were significant risk factors for surgical failure. The 1-year success rate for patients no older than 50 years of age was 23% compared with a 95% success rate in patients older than 50 years of age. After adjustment for age, type 1 diabetes was a borderline risk factor (P = 0.06). CONCLUSION: There is a high risk of long-term failure of filtering surgery with 5-FU in neovascular glaucoma. Patients 50 years of age or younger have an extremely poor prognosis. Patients older than 50 years of age have initial short-term success with an accelerated failure rate after 3 years.

Adolescent↗