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991.
992.
993.
Adam S Hassan Mark W Johnson Todd E Schneiderman Carl D Regillo Paul E Tornambe Lon S Poliner Barbara A Blodi Susan G Elner 《Ophthalmology》1999,106(10):1900-1907
Objective
To investigate the efficacy and safety of treating thick submacular hemorrhages with intravitreous tissue plasminogen activator (tPA) and pneumatic displacement.Design
Retrospective, noncomparative case series.Participants
From 5 participating centers, 15 eligible patients had acute (<3 weeks) thick subretinal hemorrhage involving the center of the macula in eyes with pre-existing good visual acuity. Hemorrhages were secondary to age-related macular degeneration in 13 eyes and macroaneurysm and trauma in 1 eye each.Methods
The authors reviewed the medical records of 15 consecutive patients who received intravitreous injection of commercial tPA solution (25–100 μg in 0.1–0.2 ml) and expansile gas (0.3–0.4 ml of perfluoropropane or sulfur hexafluoride) for thrombolysis and displacement of submacular hemorrhage. After surgery, patients maintained prone positioning for 1 to 5 days (typically, 24 hours).Main outcome measures
Degree of blood displacement from under the fovea, best postoperative visual acuity, final postoperative visual acuity, and surgical complications.Results
In 15 (100%) of 15 eyes, the procedure resulted in complete displacement of thick submacular hemorrhage out of the foveal area. Best postprocedure visual acuity improved by 2 lines or greater in 14 (93%) of 15 eyes. After a mean follow-up of 10.5 months (range, 4–19 months), final visual acuity improved by 2 lines or greater in 10 (67%) of 15 eyes and measured 20/80 or better in 6 (40%) of 15 eyes. Complications included breakthrough vitreous hemorrhage in three eyes and endophthalmitis in one eye. Four eyes developed recurrent hemorrhage 1 to 3 months after treatment, three of which were retreated with the same procedure.Conclusions
Intravitreous injection of tPA and gas followed by brief prone positioning is effective in displacing thick submacular blood and facilitating visual improvement in most patients. The rate of serious complications appears low. Final visual outcomes are limited by progression of the underlying macular disease in many patients. 相似文献994.
Marcus DM Camp MW Sheils WC McIntosh SB Leibach DB Johnson MH Samy CN 《Retina (Philadelphia, Pa.)》1999,19(6):525-530
BACKGROUND: To evaluate the effectiveness of sham radiation treatments in masking patients to their randomization group in the Radiation of Age-Related Macular Degeneration (ROARMD) Study. METHODS: Patients with choroidal neovascularization complicating age-related macular degeneration were randomized to a treatment (RAD) group that received external beam irradiation (seven treatment sessions) or to a control (SHAM) group that received sham radiation (one sham treatment session). During a telephone survey, 62 of 73 randomized patients responded to the following questions: Do you think you received radiation? Why do you feel that way? Did the vision in your study eye worsen after enrollment? RESULTS: Eighty-one percent of the RAD group and 59% of the SHAM group thought that they had received radiation. In patients who thought that their vision had stabilized or improved, 82% thought that they had received radiation. In patients who thought that their vision was worse, only 39% thought that they had received radiation. In 54% of patients, subjective perception of vision influenced their guess as to whether they received radiation. CONCLUSIONS: Subjective patient perception of visual outcome was the most influential variable for masking. Variation between radiation treatment and sham session techniques, such as equipment used and duration of treatments, played a lesser role in the masking of patients. Seven treatment days correlated with a higher number of patients who thought that they had received radiation. Although our procedures do not strictly mask the two groups, one sham radiation session was effective in keeping patients guessing their randomization group. 相似文献
995.
T E Johnson D T Tse G E Byrne A Restrepo C C Whitcomb W Voigt P Benedetto V Curtin 《Ophthalmic plastic and reconstructive surgery》1999,15(3):171-179
PURPOSE: To determine whether molecular genetic analysis of ocular-adnexal lymphoid tumors, combined with histopathology and tumor location, is helpful in predicting which patients will develop systemic lymphoma. METHODS: A combined retrospective and prospective study of 77 patients with ocular-adnexal lymphoid tumors was performed. The tumors were subdivided into conjunctival, orbital, and eyelid lesions, and all were studied using both routine histopathology and molecular genetic analysis. RESULTS: Most lesions (70%) were small cell lymphomas of the mucosa-associated lymphoid tissue type, and the majority of tumors (90%) contained monoclonal or oligoclonal populations of lymphocytes discovered on molecular genetic analysis. Additionally, 72% of tumors exhibiting clonality had more than one gene rearrangement. Fifty-three percent of patients developed extraocular lymphoma sometime during the course of their disease. Patients with gene rearrangements on Southern blot hybridization had a 52% incidence of nonocular disease, compared with 63% of those without rearrangements. Patients with conjunctival tumors had a 37.5% incidence of nonocular disease, those with orbital tumors had a 54% incidence, and those with eyelid tumors had a 100% incidence of nonocular lymphoma. Only two patients died as result of systemic lymphoma. CONCLUSIONS: Most ocular-adnexal lymphoid tumors are lymphomas of the mucosa-associated lymphoid tissue type. The majority of tumors exhibit gene rearrangements on molecular genetic analysis, and this technique was not helpful in predicting which patients would develop nonocular lymphoma. Tumor location did have predictive value: Conjunctival lesions had the lowest incidence of nonocular lymphoma, and lid lesions had the highest incidence. Even with disseminated disease, most patients have a favorable prognosis with treatment. 相似文献
996.
997.
PURPOSE: To report the accuracy of telemedical slit-lamp evaluation in examination of ocular adnexa and anterior segment. METHODS: By means of contingency tables, slit-lamp findings by live examination and by real-time telemedicine were compared in 50 eyes of 25 patients. RESULTS: Sensitivity percentages (proportion with findings correctly identified by telemedicine)/specificity percentages (proportion without the finding that was correctly identified by telemedicine) were 100/64 for eyelid mass, 100/85 for conjunctival pigment, 100/100 for posterior synechiae, 80/0 for blepharitis, 83/93 for iridotomy, 70/93 for pinguecula, 75/93 for iris lesions, 56/98 for corneal scar, 0/100 for chamber inflammation, 57/93 for nuclear cataract, and 37/100 for intraocular lens presence. CONCLUSIONS: By means of monocular slit-lamp telemedical evaluation, clinical findings with high contrast cues for color and depth have the highest sensitivity and specificity. 相似文献
998.
P Sullivan G A Cioffi L Wang C A Johnson E M Van Buskirk K R Sherman D R Bacon 《American journal of ophthalmology》1999,128(1):81-87
PURPOSE: To determine the effect of the cardiac cycle on scanning laser Doppler flowmeter measurements of retinal capillary blood flow in rhesus monkeys and humans. METHODS: Multiple scanning laser Doppler flowmetry images of rhesus monkey and human retinal capillary blood flow over a range of heart rates were obtained. Average flow values were determined for the 64 scan lines that compose the two-dimensional flow map. Cutaneous blood flow was measured simultaneously with a laser Doppler flowmeter. The temporal relationships between retinal capillary blood flow, peripheral arterial pulse, and cutaneous blood flow were determined. In addition, human retinal capillary blood flow in a 10 x 10-pixel area during different phases of the cardiac cycle was compared. RESULTS: Regular oscillations in human and rhesus monkey retinal capillary blood flow are evident as alternating bright and dark horizontal bands in scanning laser Doppler flowmetry images. These fluctuations are temporally correlated with cutaneous blood flow. Linear regression of actual vs predicted heart rate based on peaks in retinal capillary flow yielded r = 0.999 in a rhesus monkey and 0.938 in a human. Retinal capillary blood flow in a 10 x 10-pixel area fluctuated as much as 50% depending on the phase of the cardiac cycle. CONCLUSIONS: The alternating bright and dark banding pattern observed in scanning laser Doppler flowmetry scans of retinal capillary blood flow is related to the cardiac pulse. The errors introduced by pulse-related fluctuations in retinal capillary blood flow are significant and must be minimized or corrected for accurate and reproducible measurements of ocular hemodynamics. 相似文献
999.
PURPOSE: To evaluate the effect of contact transscleral diode cyclophotocoagulation on intraocular pressure (IOP), vision, number of medications, and complications in a heterogenous population of patients with refractory glaucoma. METHODS: Clinical data for all patients undergoing contact transscleral diode cyclophotocoagulation for refractory glaucoma at the Medical College of Georgia between November 1994 and November 1996 were reviewed. Forty-seven eyes of forty-seven patients followed for at least one month were included. Visual acuity, IOP, number of medications, and complications were noted for follow-up periods as long as 24 months. RESULTS: At final follow-up examination (range 1-24 months, median 9 months), the average decrease in IOP was 21+/-16 mmHg. Thirty-one (66%) patients had final IOP between 7 and 21 mmHg. Medications were decreased by an average of 1.1. Twenty-six (62%) of 42 patients with vision before surgery had stable or improved visual acuity at the final follow-up visit; 16 (38%) had a deterioration in visual acuity. Neovascular glaucoma was associated with a posttreatment IOP less than 7 mmHg. CONCLUSION: Contact transscleral diode cyclophotocoagulation is effective in lowering IOP in eyes with refractory glaucoma. It also serves to reduce the number of medications required for appropriate IOP control. Loss of visual acuity remains an important concern. Acute complications tend to be transient. Further study is needed to identify patients at risk for markedly reduced IOP after this procedure and for modulation of the protocol to decrease such risk. 相似文献
1000.