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R G Devenyi

Publications and source records attributed to R G Devenyi.

At least 19 recordsLinked to original sources
PubMed2001

An assessment of intraocular pressure rise in patients with gas-filled eyes during simulated air flight.

PURPOSE: To investigate the safety of aircraft flight for patients with small volumes of residual postoperative intraocular gas. DESIGN: Nonrandomized comparative trial. PARTICIPANTS: Seventeen eyes (nine gas filled and eight control eyes) of nine patients and one eye of one control subject were tested. METHODS: Patients with postoperative intraocular gas and the control subject were tested in the controlled environment of a hypobaric chamber to simulate the cabin depressurization associated with a typical commercial aircraft flight. Before, during, and after a simulated flight, the intraocular pressure (IOP) in the gas-containing and contralateral eyes was tested using the Perkins (Edinburgh, UK) and Tono-Pen XL (Jacksonville, FL) tonometers. MAIN OUTCOME MEASURES: The absolute and percentage change in IOP with varied cabin pressurization. RESULTS: Of the nine patients with intraocular gas, seven had 10% to 15% gas volume and two had 20% gas volume. In the 10% to 15% gas volume group, the IOP rose by an average of 109% from baseline during ascent to an average cabin altitude of 7429 feet above sea level. The IOP dropped to an average of 30% above baseline IOP during the cruise phase and further decreased to an average of 38% below baseline IOP on return to baseline altitude. In the 20% gas volume group, the IOP rose by an average of 84% from baseline during ascent to an average cabin altitude of 3400 feet above sea level. The IOP dropped to an average of 42% below baseline IOP on return to baseline altitude. The IOP in the contralateral control eyes did not vary with altitude changes. No patient experienced pain or visual loss during the experiments. CONCLUSIONS: Our results demonstrate that IOP may rise significantly in gas-filled eyes during simulated air flight, supporting the current conservative recommendation against air travel for most patients with intraocular gas bubbles. Further testing is warranted to develop a more objective measure of intraocular gas volume estimation and to define better the tolerability of aircraft flight for patients with intraocular gas.

Adult↗
PubMed1999

Bacterial endophthalmitis after suture removal.

We present 3 cases of endophthalmitis following suture removal after cataract surgery. In all cases, prophylactic antibiotics had been used. Treatment included vitreous tap and intravitreal antibiotic injection, with only 1 of the 3 patients regaining good visual acuity. Because povidone-iodine 5% is more effective at decreasing conjunctival bacterial counts than topical antibiotics, we recommend this method of conjunctival preparation before suture removal.

Aged↗
PubMed1999

Visual outcome following penetrating globe injuries with retained intraocular foreign bodies.

BACKGROUND: In our institution the occurrence of endophthalmitis related to intraocular foreign bodies has been rare. In this review we analyse the outcome of eyes with retained intraocular foreign bodies presenting to two vitreoretinal surgeons over nearly 7 years. METHODS: Review of the records of 26 patients who presented to two surgeons in a tertiary care vitreoretinal service in Toronto between January 1989 and November 1995. Information documented included mechanism of injury, time from injury to definitive surgery, entry site, presence of vitreous hemorrhage, type of surgery performed, initial and final visual acuity, and development of endophthalmitis. RESULTS: All the injuries occurred in male patients, with a mean age of 36.1 (range 15 to 55) years. Most of the injuries occurred in the workplace, and in most cases (17 [65.4%]) the mechanism of injury was "metal on metal." The entry site was via a perforating wound of the cornea in 16 cases (61.5%). Almost all cases were repaired within 48 hours by means of pars plana vitrectomy. Concurrent lensectomy was required in 18 cases (69.2%) for lens damage at the time of the original injury. Vitreous hemorrhage was present in 22 cases (84.6%). One patient (3.8%) manifested clinically apparent endophthalmitis, which responded to intravitreal antibiotic therapy. Nineteen eyes (73.1%) had a final visual acuity of 6/24 or better. Eyes with coexisting or subsequent retinal detachment had significantly worse vision than those without retinal detachment (p < 0.001). INTERPRETATION: The incidence of endophthalmitis in our series is lower than that in other published series. Prompt definitive treatment was associated with a good prognosis in most cases.

Accidents, Occupational↗
PubMed1997

Disordered eating behavior and microvascular complications in young women with insulin-dependent diabetes mellitus.

BACKGROUND: Insulin-dependent diabetes mellitus (IDDM) and eating disorders are relatively common among young women in North America. Their coexistence could lead to poor metabolic control and an increased risk of the microvascular complications of IDDM. METHODS: We studied 91 young women with IDDM at base line and four to five years later to determine the prevalence and persistence of disordered eating behavior (on the basis of self-reported eating and weight-loss practices, including the intentional omission or underdosing of insulin to control weight) and the association of such eating disorders with metabolic control, diabetic retinopathy, and urinary albumin excretion. At base line, the mean age of the young women was 15+/-2 years and the duration of diabetes was 7+/-4 years. RESULTS: At base line, 26 of 91 young women (29 percent) had highly or moderately disordered eating behavior, which persisted in 16 (18 percent) and improved in 10 (11 percent). Of the 65 women with normal eating behavior at base line (71 percent), 14 (15 percent) had disordered eating at follow-up. Omission or underdosing of insulin lose weight was reported by 12 of 88 young women (14 percent) at base line and 30 (34 percent) at follow-up (P=0.003). At base line, the mean (+/-SD) hemoglobin A(1c) value was higher in the group with highly disordered eating behavior (11.1+/-1.2 percent) than in the groups whose eating behavior was moderately disordered (8.9+/-1.7 percent) or nondisordered (8.7+/-1.6 percent, P<0.001). Disordered eating at base line was associated with retinopathy four years later (P=0.004), when 86 percent of the young women with highly disordered eating behavior, 43 percent of those with moderately disordered eating behavior, and 24 percent of those with nondisordered eating behavior had retinopathy. CONCLUSIONS: Disordered eating behavior is common and persistent in young women with IDDM and is associated with impaired metabolic control and a higher risk of diabetic retinopathy.

Adolescent↗
PubMed1997

Bacterial endophthalmitis following extracapsular cataract extraction: recommendations for early detection.

OBJECTIVE: To determine the time between the onset of symptoms of endophthalmitis after cataract extraction and presentation to an ophthalmologist and to determine the spectrum of organisms responsible for postoperative endophthalmitis. DESIGN: Case series. SETTING: Tertiary care vitreoretinal service in Toronto. PATIENTS: Thirty-three patients with early (presentation within 2 weeks of surgery) endophthalmitis following extracapsular cataract extraction and intraocular lens implantation performed between January 1989 and December 1992. OUTCOME MEASURES: Time to presentation to an ophthalmologist, duration of symptoms, culture results. RESULTS: Twenty-two patients (66.7%) were documented to experience identifiable symptoms of endophthalmitis before presentation to their ophthalmologist; the mean time of onset of symptoms was 3.6 (standard deviation [SD] 1.7) days after surgery. Of the 22 patients 16 (72.7%) became symptomatic by the fourth postoperative day, and 21 (95.4%) experienced symptoms by the fifth postoperative day. The mean delay between onset of symptoms and presentation was 1.9 (SD 1.6) days. Bacteria were identified in 27 cases (81.8%), confirmed by culture in 23 cases (69.7%). The organisms were gram-positive in 25 (92.6%) of the 27 cases, and coagulase-negative Staphylococcus predominated. CONCLUSIONS: In our series a considerable delay existed between the development of symptoms of endophthalmitis following extracapsular cataract extraction and clinical diagnosis. This delay could be minimized by scheduling routine postoperative visits at 1 and 4 days following cataract surgery.

Adult↗
PubMed1996

Perfluorodecalin corneal toxicity: five case reports.

Perfluorodecalin is a perfluorocarbon liquid used intraoperatively in retinal detachment repair. It is usually removed at the end of the procedure; however, residual amounts may be retained when poor corneal clarity or intraocular hemorrhage obscures the view. No clinical reports exist on the consequences of retained perfluorodecalin in the anterior segment. We report five cases in which perfluorodecalin was in prolonged contact with the cornea. The period of time for corneal pathology to occur and the role perfluorodecalin played in the etiology of such changes is discussed. A total of 348 patients with retinal detachments in one retinal practice underwent repair using pars plana vitrectomy combined with intraoperative perfluorodecalin between January 1992 and May 1994. Postoperatively, residual perfluorodecalin was observed in the anterior chamber in contact with the corneal endothelium in five patients. The patients were followed clinically for a period of up to 18 months. Four of five patients developed corneal changes from prolonged contact with perfluorodecalin. Corneal edema developed in the area perfluorodecalin-endothelial contact in three of five eyes. The period of perfluorodecalin-endothelial contact before corneal decompensation occurred ranged from 4 to 13 weeks. Two eyes required penetrating keratoplasties for progressive corneal edema. Corneal edema was reversed in one eye after removal of perfluorodecalin from the anterior chamber via multiple paracentesis. One of the remaining eyes developed deep corneal vascularization without edema in the area of perfluorodecalin contact after 12 months. These observations suggest that corneal toxicity may be induced by intraocular perfluorodecalin if it is allowed direct contact with the corneal endothelium for periods as short as 1 month. Some of these changes may be reversible if perfluorodecalin is aspirated from the anterior chamber. Further investigations are required to examine perfluorodecalin-induced corneal toxicity.

Adult↗
PubMed1995

A comparison of peribulbar and retrobulbar anesthesia for vitreoretinal surgical procedures.

OBJECTIVE: To compare the efficacy of retrobulbar and peribulbar anesthetic techniques for vitreoretinal surgical procedures. DESIGN: Prospective, randomized, double-blind study. SETTING: A large university teaching hospital. PARTICIPANTS: One hundred sixteen consecutive patients who were scheduled for vitreoretinal surgical procedures. METHODS: Patients who were undergoing vitreoretinal surgical procedures were divided into four separate groups, depending on the type of surgical procedure planned. Equal numbers of patients in each group of patients who were undergoing a surgical procedure were randomly assigned to either the retrobulbar or peribulbar block-treated group. Anesthesia, akinesia, need for block supplementation, and patient acceptance were measured. RESULTS: Both retrobulbar and peribulbar anesthetic techniques provided equal levels of akinesia and analgesia, with each requiring intraoperative supplementation in 32%. CONCLUSION: Peribulbar block can be expeditiously and efficiently used for a full range of vitreoretinal surgical procedures.

Anesthesia, Local↗
PubMed1995

Reproducibility of topographic measurements of the macula with a scanning laser ophthalmoscope.

BACKGROUND: The Heidelberg retina tomograph, a scanning laser ophthalmoscope that uses confocal optics to provide high resolution of images, is able to scan the retina in three dimensions to obtain quantitative topographic measurements. The authors evaluated its usefulness for measuring macular lesions by determining the reproducibility of its topographic measurements at the macula. METHODS: For each of ten healthy patients, the authors took five images with the patient's right eye undilated and five with the eye cyclopleged and dilated. As a measure of reproducibility, the standard deviation of height measurements for the same location at the macula was calculated for each patient and then the pooled standard deviation for all patients was calculated. The authors performed similar calculations for the mean depth within a contour line. RESULTS: The pooled standard deviation for height measurements was 47.4 microns in undilated eyes and 36.0 microns in cyclopleged, dilated eyes. The authors obtained an extremely low standard deviation of 2.2 microns when the software calculated relative differences between measurements, such as the mean depth within a contour line. When the average of three height measurement values on 1 day was compared with the average of the three values on another day, the 95% confidence interval was +/- 58.7 microns for mean height values and +/- 3.7 microns for mean depth values within a contour line. CONCLUSIONS: The authors obtained good reproducibility for height measurements with the Heidelberg retina tomograph and excellent reproducibility when the instrument calculated relative differences in height measurements. The authors recommend that patients, especially young patients, be dilated and cyclopleged to obtain lower variability of measurements. The scanning laser ophthalmoscope could potentially be used to quantify small changes in retinal lesions.

Adult↗
PubMed1994

Mortality of hospitalized patients with Candida endophthalmitis.

BACKGROUND: Candida is becoming an important nosocomial pathogen as the incidence of hospital-acquired candidemia is rising. Candida endophthalmitis is a good indicator of systemic candidiasis in hospitalized patients. METHODS: Thirteen (17%) of 76 ophthalmologic consultations for Candida endophthalmitis in our institution had positive findings during a 12-month period. We studied these 13 patients with Candida endophthalmitis to evaluate their outcomes. RESULTS: All 13 patients were admitted to a large tertiary care hospital, and 10 (77%) were in an intensive care unit. The overall mortality was 77% for all patients and 80% for the intensive care patients. This mortality was higher than the overall mortality for all patients in the surgical intensive care unit in our institution (17%), as well as the mortality for our patients with candidemia in the surgical intensive care unit (61%). CONCLUSIONS: The strikingly high mortality in our group of patients with Candida endophthalmitis reflects the fact that they are a seriously ill group with multiple risk factors for Candida infection. This information suggests that the presence of Candida endophthalmitis is a good indicator of high mortality in seriously ill patients in intensive care units.

Adult↗