Showing papers in "Ophthalmic Surgery and Lasers in 2000"
TL;DR: Tomographic imaging is demonstrated in vitro in the peripapillary area of the retina and in the coronary artery, two clinically relevant examples that are representative of transparent and turbid media, respectively.
Abstract: A technique called optical coherence tomography (OCT) has been developed for noninvasive cross-sectional imaging in biological systems. OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way that is analogous to ultrasonic pulse-echo imaging. OCT has longitudinal and lateral spatial resolutions of a few micrometers and can detect reflected signals as small as approximately 10(-10) of the incident optical power. Tomographic imaging is demonstrated in vitro in the peripapillary area of the retina and in the coronary artery, two clinically relevant examples that are representative of transparent and turbid media, respectively.
2,145 citations
TL;DR: TTT may be useful not only as independent therapy, but also as an adjunct to PDT, antiangiogenic drugs and ionizing radiation therapy in the management of neovascular ARMD and perhaps even for treating glaucoma or retinal degenerations.
Abstract: Objective To provide a biophysical foundation for using transpupillary thermotherapy (TTT) to manage choroidal neovascularization in age-related macular degeneration (ARMD). Methods Retinal temperature rise in laser therapy is proportional to retinal irradiance (laser power/area) for a particular spot size, exposure duration, and wavelength. TTT is a low irradiance, large spot size, prolonged exposure (long-pulse), infrared laser photocoagulation protocol. Results from an experimentally confirmed, finite element model of retinal light absorption and heat conduction are used to analyze laser parameter selection and its consequences. Results from apoptosis, heat shock protein and hyperthermia research are used to examine how chorioretinal damage from clinical procedures might be reduced. Results Chorioretinal thermal equilibration occurs during long-pulse TTT photocoagulation. Retinal temperature increases are similar in the RPE where laser radiation absorption is significant and in the adjacent neural retina where there is negligible radiation absorption. For parameters used to treat occult choroidal neovascularization in lightly-pigmented fundi (800-mW, 810-nm, 3-mm retinal spot diameter, 60-sec exposure duration), the maximum chorioretinal temperature elevation is calculated to be roughly 10 degrees C, significantly lower than the 20 degrees C temperature elevations measured in threshold, conventional short-pulse retinal photocoagulation. Conclusions To achieve a preselected temperature rise, TTT laser power must be increased or decreased in proportion to the diameter rather than the area of the laser spot. Clinical power settings should be adjusted for fundus pigmentation and media clarity because both of these factors affect absorbed retinal irradiance and thus retinal temperature rise. Noninvasive thermal dosimetry currently is unavailable for clinical retinal photocoagulation, but potential thermometric techniques include MRI, liposomal-encapsulated dyes, multispectral imaging or reflectometry, and subretinal or episcleral thermometry. TTT may be useful not only as independent therapy, but also as an adjunct to PDT, antiangiogenic drugs and ionizing radiation therapy in the management of neovascular ARMD. Low temperature, long-pulse photocoagulation is a potential strategy for decreasing neural retinal damage in subsequent TTT or short-pulse photocoagulation and perhaps even for treating glaucoma or retinal degenerations.
203 citations
TL;DR: Significant differences of retinal thickness between patients with diabetic retinopathy and normals can be detected by OCT even in the absence of clinically significant macular edema.
Abstract: BACKGROUND AND OBJECTIVE: To evaluate the potential of optical coherence tomography (OCT) as a screening method for retinal thickness measurements in diabetic patients. PATIENTS AND METHODS: We used a previously described pattern of six 5 mm OCT scans through the center of fixation in 45 diabetic patients without clinically significant macular edema: 22 patients (group 1) had no diabetic retinopathy (ETDRS classification); 18 (group 2) had nonproliferative retinopathy; 5 patients with peripheral neovascularization did not enter statistical analysis; 25 normal healthy subjects were used as a control group. Retinal thickness was measured at five locations in each scan: in the fovea, at the foveal rim, and outside the macula. Measurements were identified in nonaligned images and taken from raw data A-scans. Locations were grouped into hemispheres, quadrants and rings, and mean values tested for statistically significant differences using Mann-Whitney U-Wilcoxon rank sum W test. RESULTS: Differences in retinal thickness were found to be significant in the macula (controls vs group 2 P = 0.0266), at the foveal rim (controls vs group 1 and 2: P = 0.0386 and P = 0.0193), in the nasal and superior hemisphere (controls vs group 2: P = 0.0251 and P = 0.0187), and in the superior nasal quadrant (controls vs group 1 and group 1 vs group 2: P = 0.0022 and P = 0.0462). CONCLUSIONS: Significant differences of retinal thickness between patients with diabetic retinopathy and normals can be detected by OCT even in the absence of clinically significant macular edema. Significant differences between diabetic patients with and without retinopathy are most likely to be found in the superior nasal quadrant.
108 citations
TL;DR: It is concluded that conjunctival autograft and intraoperative mitomycin-C are both equally effective adjuncts to primary pterygium surgery on long term follow-up.
Abstract: ■ PURPOSE: To evaluate and compare the long term safety and efficacy of low-dose intraoperative application of mitomycin-C (0.02%) with conjunctival autograft in primary pterygium surgery. ■ PATIENTS AND METHODS: Of 37 consecutive patients 41 eyes with primary pterygium underwent pterygium excision with either intraoperative mitomycin-C (0.02%) (Group I) or conjunctival autografts (Group II) at random. Mitomycin-C (0.2 mg/mL) was applied for 2.5 minutes on the scleral bed under the conjunctiva. Conjunctival autograft was obtained from upper temporal limbus and secured with 10-0 monofilament nylon. The follow-up period ranged from 14 to 54 months (mean 36 months) for mitomycin-C group and 13 to 58 months (mean 38 months) for conjunctival autograft group. ■ RESULTS: Twenty-one eyes underwent pterygium excision with intraoperative mitomycin-C (0.02%) application (Group I) and 20 eyes were treated using conjunctival autograft (Group II). The mean size of the pterygium was 3.80 mm (range 2.6 to 4.8 mm) in the mitomycin-C group and 3.60 mm (range 2.5 to 4.5 mm) in the conjunctival autograft group. Two (9.52%) eyes treated with intraoperative mitomycin-C had delayed epithelial healing of corneoscleral wound and one (4.76%) eye developed pyogenic granuloma. Three (14.3%) of the 21 eyes in Group I and one (5%) of 20 eyes in Group II had recurrence of pterygium (P = 0.3174). All recurrences occurred in patients below 40 years of age (P = 0.0384). ■ CONCLUSION: We conclude that conjunctival autograft and intraoperative mitomycin-C are both equally effective adjuncts to primary pterygium surgery on long term follow-up. However, future prospective studies with larger numbers of subjects may be carried out to find out the optimum concentration and duration of intraoperative mitomycin-C application.
82 citations
TL;DR: Use of a gas tamponade in the combined surgery group increased the myopic change and was thought to have pressed the intraocular lens forward, which shifted toward myopia when compared with the controls.
Abstract: Purpose To evaluate the effect of vitrectomy on postoperative refraction after simultaneous vitrectomy and cataract surgery. Methods We compared the spread between predicted and actual refractions in 206 eyes after a simultaneous vitrectomy, phacoemulsification, aspiration and acrylic lens insertion (combined surgery group), and in 67 eyes after cataract surgery only (cataract surgery group) as control. A vitrectomy was performed for diabetic retinopathy in 127 eyes, macular hole in 32 eyes, rhegmatogenous retinal detachment in 16 eyes, branch retinal vein occlusion in 15 eyes, and other conditions in 26 eyes. In the combined surgery group, 79 eyes had a gas tamponade after insertion of the intraocular lens. Results The spread between predicted and actual refractions was - 0.05 +/- 1.18 diopters (average +/- SD) in the combined surgery group and +0.55 +/- 1.32 D in the cataract surgery group. The actual refractive errors in the combined surgery group were found to shift toward myopia when compared with the controls. Among the combined surgery group, 127 eyes without a gas tamponade showed a postoperative refractive error of +0.14 +/- 1.11 D, while 79 eyes with a gas tamponade demonstrated an error of -0.36 +/- 1.22 D. Conclusions Use of a gas tamponade in the combined surgery group increased the myopic change and was thought to have pressed the intraocular lens forward.
78 citations
TL;DR: Up to 4 mg of triamcinolone acetonide can be safely injected in silicone-filled, vitrectomized eyes without any significant retinal toxicity.
Abstract: ■ OBJECTIVE: To determine the retinal toxicity of triamcinolone acetonide at different doses in vitrectomized, silicone-filled rabbit eyes. ■ MATERIALS AND METHODS: Vitrectomy with silicone oil placement was performed in 32 rabbit eyes. A dosage of 1 mg/0.025 mL, 2 mg/0.05 mL, or 4 mg/0.1 mL of triamcinolone acetonide was injected intravitreally in the study group eyes; the control group received 0.1 mL of sterile saline. Electroretinography and retinal histology were performed to evaluate toxicity. ■ RESULTS: No retinal toxicity was seen in the groups given 1, 2, and 4 mg of triamcinolone acetonide or in the control group. ERG and histologic sections in all groups were normal. No drug was visible in the vitreous cavity at the end of the 140-day period (average) in eyes injected with 4 mg of triamcinolone acetonide. ■ CONCLUSIONS: Up to 4 mg of triamcinolone acetonide can be safely injected in silicone-filled, vitrectomized eyes without any significant retinal toxicity.
72 citations
TL;DR: Sutureless sclerotomies are simple to perform, save operative time, and reduce the risk of peroperative hypotony following removal of instruments or the infusion cannula.
Abstract: ■ OBJECTIVE: To determine the efficacy of self-sealing pars plana sclerotomies for vitrectomy and to identify complications associated with this new technique. ■ METHOD: There were 150 self-sealing sclerotomies performed in 50 patients undergoing pars plana vitrectomy between October 1996 and March 1998. ■ RESULTS: Of the 150 sclerotomies, 115 (76.6%) did not require suturing while 35 (23.3%) were closed with one radial 7.0 vicryl suture. The scleral tunnel incisions ensured minimal loss of intraocular fluids during instrument exchange and scleral plugs were not required to avoid ocular hypotony during scleral indentation. Distortion of scleral flap incisions requiring a suture were commonly seen in procedures using multiple instrumentations and extensive explants. ■ CONCLUSIONS: Sutureless sclerotomies are simple to perform, save operative time, and reduce the risk of peroperative hypotony following removal of instruments or the infusion cannula. The technique reduces postoperative inflammation, suture-related problems including astigmatism, and allows more rapid rehabilitation.
64 citations
TL;DR: It is suggested that Nd:YAG laser iridotomy may pose a long-term hazard to the corneal endothelium and significant endothelial cell loss in the 1-year follow-up is demonstrated.
Abstract: ■ BACKGROUND AND OBJECTIVE: This study examined the long-term effect of neodynium:YAG (Nd:YAG) laser iridotomy on the corneal endothelium. ■ PATIENTS AND METHODS: A prospective study was designed. Patients with narrow and occludable angles or fellow eye of acute angle closure glaucoma attack were treated with Nd:YAG laser iridotomy. For one year, 31 eyes of 21 patients underwent complete follow-up. Corneal endothelial specular microscopy was performed before and after laser iridotomy at 1, 3, 6, and 12 months. ■ RESULTS: The decrease of endothelial cell density after YAG laser iridotomy was statistically significant at 1 month (P = 0.036), 6 months (P = 0.004), and 12 months (P = 0.000), respectively. The decrease was not statistically significant at 3 months (P = 0.467). Linear regression analysis indicated no statistical correlation between the percentage change in endothelial cell density and the total energy used during the treatment (1 month: P = 0.08, 3 months: P = 0.3, 6 months: P = 0.9, 12 months: P = 0.2). ■ CONCLUSION: This study demonstrated significant endothelial cell loss in the 1-year follow-up. The result suggested that Nd:YAG laser iridotomy may pose a long-term hazard to the corneal endothelium.
57 citations
TL;DR: A 70-year-old Asian female with narrow angles underwent ultrasound biomicroscopy (UBM) darkroom provocative testing and the angle was narrow under light conditions and occluded in the dark, except for the inferior quadrant where the angles were wide and the iris concave.
Abstract: A 70-year-old Asian female with narrow angles underwent ultrasound biomicroscopy (UBM) darkroom provocative testing The angle was narrow under light conditions and occluded in the dark, except for the inferior quadrant where the angle was wide and the iris concave This was reproducible in four quadrants with the use of a small UBM eye cup but not the large one A small eye cup can indent the cornea, resulting in artifactitious angle widenening Care must be taken when using the small eye cup not to press on the cornea
56 citations
TL;DR: OCT is a useful tool for evaluating and documenting CSME both before and after focal/grid laser photocoagulation in clinically significant macular edema secondary to diabetes.
Abstract: BACKGROUND AND OBJECTIVE: To demonstrate the utility of optical coherence tomography (OCT) for documenting an early response to laser photocoagulation in clinically significant macular edema (CSME) secondary to diabetes. PATIENTS AND METHODS: Five eyes of four patients were selected for review based on the diagnosis of CSME. All eyes had a clinical diagnosis of CSME based on slit lamp biomicroscopy. All eyes underwent focal/grid laser photocoagulation to areas of retinal thickening detected by OCT and clinical exam. Pre and post-treatment optical coherence tomograms were obtained for all patients. RESULTS: All eyes selected for review had an early positive response to focal laser photocoagulation. OCT was useful for demonstrating areas of retinal thickening prior to laser treatment. Serial macular maps demonstrated the resolution of retinal thickening after laser photocoagulation in all eyes. CONCLUSION: OCT is a useful tool for evaluating and documenting CSME both before and after focal/grid laser photocoagulation. OCT is capable of detecting an early positive response to photocoagulation for macular edema.
56 citations
TL;DR: In this retrospective case series with relatively short follow-ups, AGV implantation with mitomycin C in refractory glaucoma appears to be effective without increased complication rates.
Abstract: ■ OBJECTIVE: To study the surgical outcome and complications of Ahmed glaucoma valve (AGV) implantation with mitomycin C (MMC) in refractory glaucoma. ■ PATIENTS AND METHODS: The authors retrospectively reviewed the records of 40 eyes in 37 consecutive patients who underwent combined AGV with MMC (0.4 mg/mL; 5 minutes). All patients had a minimum of 6 months of follow-up. Outcome measures were best corrected visual acuity, intraocular pressure (IOP), the number of medications, success rates, and the incidence of complications. ■ RESULTS: The Kaplan-Meier life table analysis revealed that the probabilities of surgical success based on our success criteria at 1 year and 2 years postoperatively were 80% and 77%, respectively. Postoperative IOP was significantly lower at all follow-up intervals. At the final visit fewer glaucoma medications were used (2.5 vs 0.7, preoperative vs postoperative). The most frequent complication was hypotony (17%). ■ CONCLUSION: In this retrospective case series with relatively short follow-ups, AGV implantation with mitomycin C in refractory glaucoma appears to be effective without increased complication rates.
TL;DR: The use of infrared OCT allows penetration of the sclera, thus, providing complete visualization of the anterior chamber angle and limited demonstration of the ciliary body, and may represent an interesting noninvasive alternative to ultrasound biomicroscopy.
Abstract: BACKGROUND AND OBJECTIVE: To evaluate the potentials of optical coherence tomagraphy (OCT) using long wavelength to penetrate highly scattering tissues of the eye and visualize the anterior chamber angle and the ciliary body. METHODS: OCT images were generated by an experimental prototype in enucleated porcine eyes using as light source a superluminiscent diode with a wavelength of 1310 nm and a scan frequency of 60 Hz. The number of lateral scans was variable in a range from 100 to 400. RESULTS: Infrared OCT was able to penetrate the sclera. The anterior chamber angle could be visualized completely and the ciliary body could be identified. However, it was not possible to penetrate the highly reflective iris pigment epithelium. CONCLUSION: The use of infrared OCT allows penetration of the sclera, thus, providing complete visualization of the anterior chamber angle and limited demonstration of the ciliary body. Because of its higher resolution, it may represent an interesting non-invasive alternative to ultrasound biomicroscopy.
TL;DR: A 47-year-old male suffered from an alkali injury complicated with corneal melting and perforation in the left eye with vision 20/25 six months after the operation and the combined use of an amniotic membrane and tissue adhesive is a promising method in the treatment.
Abstract: We report a new method combining the use of an amniotic membrane and cyanocrylate tissue adhesive to seal a corneal perforation. A 47-year-old male suffered from an alkali injury complicated with corneal melting and perforation in the left eye. We placed an amniotic membrane of optimal size in the anterior chamber directly under the corneal perforation lesion. The cyanocrylate tissue adhesive was then applied over the perforation site and sealed successfully. Three weeks later, the tissue adhesive had dislodged. The amniotic membrane had sealed the perforated lesion and was well adhered to the surrounding corneal tissue with complete epithelial covering. Vision was 20/25 six months after the operation. The combined use of an amniotic membrane and tissue adhesive is a promising method in the treatment of corneal perforation.
TL;DR: The abnormal vessel associated with IPCV is supposed to be choroidal neovascularization with polypoidal dilatations at the terminals between Bruch's membrane and RPE.
Abstract: BACKGROUND AND OBJECTIVE: To identify the histological level of abnormal vessels associated with idiopathic polypoidal choroidal vasculopathy (IPCV), we examined IPCV with Optical Coherence Tomography (OCT). PATIENTS AND METHODS: Fourteen patients diagnosed with IPCV were examined with Indocyanine green (ICG) angiography and OCT. RESULTS: ICG angiography demonstrated branching vascular networks with polypoidal dilatations at the terminals beneath the retinal pigment epithelium (RPE). OCT showed dome-like elevation of the RPE, and moderate reflex or nodular appearance were seen beneath the RPE. CONCLUSION: The abnormal vessel associated with IPCV is supposed to be choroidal neovascularization with polypoidal dilatations at the terminals between Bruch's membrane and RPE. We consider that this disease is a peculiar form of age-related macular degeneration.
TL;DR: This study suggests the possible association between retinal detachment and LASIK procedure in patients with myopia and Clinicians should be aware of retinal pathology predisposing toretinal detachment in patients undergoing LASik.
Abstract: ■ OBJECTIVE: To report the clinical characteristics, surgical management and outcome of retinal detachment following laser in situ keratomileusis (LASIK) in myopic patients. ■ PATIENTS AND METHODS: Retrospective review of 10 eyes of 10 myopic patients with retinal detachment who had previously undergone LASIK surgery were analyzed. Included in the study were 7 males and 3 females, aged 22 to 68 years (35.2±2.8). ■ RESULTS: Mean spherical equivalent refraction was -10.51±3.90 D (ranging from -6.37 D to -17.00 D) before surgery. The time interval between the LASIK procedure and the development of retinal detachment varied from two months to nine months (5.2±2.78 months). The number of retinal breaks was one in 7 patients, two in 2 patients and three in 1 patient. The type of retinal breaks included 7 patients with horse shoe tears, 1 patient with a retinal hole, 1 patient with a giant retinal tear, and 1 patient with retinal dialysis. Retinal breaks were located anterior to the equator in 9 patients and posterior to the equator in 1 patient. Retinal reattachment was achieved with one operation in 8 eyes (80%) and the remaining 2 eyes required a second surgery for the reattachment of the retina. ■ CONCLUSION: This study suggests the possible association between retinal detachment and LASIK procedure in patients with myopia. Clinicians should be aware of retinal pathology predisposing to retinal detachment in patients undergoing LASIK.
TL;DR: OCT appears to be a useful tool in the diagnosis and management of diabetic macular edema and in the monitoring of the morphological changes after vitrectomy.
Abstract: BACKGROUND AND OBJECTIVE: To assess the role of optical coherence tomography (OCT) in the evaluation and follow-up after vitrectomy for diabetic macular edema. MATERIALS AND METHODS: The 18 eyes of 12 patients affected by presumed diabetic vitreous-induced macular edema underwent biomicroscopy with a Goldmann contact lens, fluorescein angiography, and OCT. RESULTS: OCT revealed two patterns of edema. The first group (15 eyes) was characterized by widespread thickening of the neurosensory retina with an increased nonhomogeneous reflectivity of the inner retinal layers; cystoid-like spaces of absent or reduced reflectivity in the neurosensory retina were also present. In the second group (3 eyes), a cystoid macular edema with a dome-shaped foveal profile because of a markedly increased retinal thickness in the foveal region was observed. The disappearance of the physiologic foveal profile was always seen. Biomicroscopy revealed an increased reflex of the inner limiting membrane in the first group and minimal alterations in the second one. Four patients (7 eyes) underwent vitrectomy with posterior hyaloid removal. In 5 eyes, the patients experienced a visual improvement greater than two Snellen lines. The restoration of the normal foveal profile and the reduction of the retinal thickness on the OCT were evident in all cases one month after surgery. CONCLUSION: OCT appears to be a useful tool in the diagnosis and management of diabetic macular edema and in the monitoring of the morphological changes after vitrectomy.
TL;DR: Retinal vein cannulation may offer a new treatment option for patients with central retinal vein occlusion and a modest improvement in visual acuity was demonstrated in 4 of the 8 eyes.
Abstract: Vitreous surgery with retinal vein cannulation and injection of tissue plasminogen activator was performed in 8 eyes of 8 patients with longstanding visual loss secondary to central retinal vein occlusion. A modest improvement in visual acuity was demonstrated in 4 of the 8 eyes, and 3 of the 8 eyes maintained the preoperative vision. Retinal vein cannulation may offer a new treatment option for patients with central retinal vein occlusion.
TL;DR: The preliminary study suggests that IL-6, IL-8, and NO might be dominant contributing factors in the occurrence of the inflammation postoperatively.
Abstract: OBJECTIVE: To determine the levels of nitric oxide (NO) and cytokines such as interleukin 1-beta (IL-1beta), interleukin 6 (IL-6), interleukin 8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha) on vitreous humor following retinal laser photocoagulation. MATERIALS AND METHODS: The rabbits were divided into 3 groups of 4 animals (8 eyes) each. Twelve pigmented rabbit eyes underwent modified grid pattern photocoagulation with a power of 240 mW (group I); 300 mW (group II); and 360 mW (group III). The eyes received 200 burns using a spot size of 200 micro, and duration of 0.2 s. Vitreous humor samples were collected from each eye preoperatively and at 24 and 72 hours after the laser. RESULTS: When compared to preoperative levels, IL-6 levels were increased in all groups; IL-1beta levels were increased significantly only in group III. IL-8 levels were high in groups II and III only at 72 hours (P <0.05). TNFalpha levels were elevated significantly in group II and III only at 24 hours (P <0.05). NO levels were significantly higher than preoperative values in all groups at all times. CONCLUSION: Our results support that especially IL-6, IL-8, and NO levels increase significantly following laser photocoagulation. This preliminary study suggests that IL-6, IL-8, and NO might be dominant contributing factors in the occurrence of the inflammation postoperatively.
TL;DR: The results indicate that uncomplicated cataract surgery does not influence retinal thickness immediately postoperatively in eyes without ocular pathologies.
Abstract: BACKGROUND AND OBJECTIVE: To evaluate changes in retinal thickness immediately after cataract surgery. PATIENTS AND METHODS: Retinal thickness before and 0.5 hours after uneventful cataract surgery was determined in 10 patients at 15 different points at the posterior pole by optical coherence tomography (OCT). RESULTS: The mean retinal thickness at the posterior pole was 251 microm (+/-30 microm) before cataract surgery and 249 microm (+/-25 microm) after cataract surgery. No statistical difference between pre- and postoperatively values could be evaluated (P = 0.8). CONCLUSIONS: The results indicate that uncomplicated cataract surgery does not influence retinal thickness immediately postoperatively in eyes without ocular pathologies.
TL;DR: Infrared diode laser TTT provides a useful modality in the treatment of retinal capillary hemangiomas, and may be particularly favorable for peripapillary lesions because of its relatively nondestructive characteristics.
Abstract: Retinal capillary hemangiomas are a common manifestation of von Hippel-Lindau disease. We report the treatment of a peripapillary retinal capillary hemangioma in the left eye of a 30-year-old woman with this condition, using infrared diode laser transpupillary thermotherapy (TTT). The hemangioma was evaluated before and after treatment by ophthalmoscopy, fundus fluorescein angiography, and Doppler ultrasonography. Infrared diode laser TTT was delivered over 3 sessions during a period of 22 weeks, resulting in an improvement in visual acuity from counting fingers to 6/24 and a marked decrease in exudates surrounding the hemangioma. Doppler ultrasonography demonstrated a decrease in intralesional blood flow from 7 cm per second to less than 3 cm per second, together with a decrease in the size of the lesion. Infrared diode laser TTT provides a useful modality in the treatment of retinal capillary hemangiomas, and may be particularly favorable for peripapillary lesions because of its relatively nondestructive characteristics.
TL;DR: Vitrectomy is worthy of consideration when macular edemas are prolonged in patients of CRVO and optical coherence tomography is a useful instrument for management and treatment of Macular edema.
Abstract: PURPOSE AND OBJECTIVE To report retina tomography after vitrectomy for macular edema in central retinal vein occlusion (CRVO). PATIENTS AND METHODS Five patients with macular edema caused by CRVO were examined using optical coherence tomography (OCT) through their clinical courses. RESULTS The retinal thickness through the fixation was reduced in all 5 eyes. Preoperatively, the retina thickness at the foveola was more than 500 microm in three eyes and more than 1000 microm in 2 eyes. The retina thickness was reduced to 311+80 microm within two weeks on average. Visual acuity was improved by two or more lines in 3 of 5 eyes. CONCLUSION Vitrectomy is worthy of consideration when macular edemas are prolonged in patients of CRVO. OCT is a useful instrument for management and treatment of macular edema.
TL;DR: In patients with temporal side retinal detachment only, segmental scleral buckling provides adequate treatment for stage 4 ROP.
Abstract: ■ BACKGROUND AND OBJECTIVE: Both vitrectomy and scleral buckling have been used to treat patients with stage 4 retinopathy of prematurity (ROP). The standard procedure of scleral buckling for treatment of stage 4 ROP is encircling scleral buckling. The effectiveness of segmental scleral buckling is still unclear. The purpose of this study was to analyze the surgical results of patients with stage 4 retinopathy of prematurity treated with either encircling or segmental scleral buckling. ■ PATIENTS AND METHODS: We retrospectively analyzed the anatomic outcomes of 23 eyes (18 infants) with stage 4 A or B ROP treated with scleral buckling. Segmental buckling was used to treat 15 eyes with detachment limited to the temporal side of the retina, while 9 eyes with detachment involving both the nasal and temporal sides were treated with encircling scleral buckling. ■ RESULTS: Macular reattachment during a mean follow-up periord of 34 months (range: 2 weeks to 9 years) was accomplished in 11 (79%) of the 14 eyes treated with segmental scleral buckling and 4 (44%) of the 9 eyes that received encircling scleral buckling. There were no intraoperative complications recorded. None of the eyes that achieved macular reattachment developed recurrent macular detachment during the follow-up period. ■ CONCLUSIONS: Scleral buckling appears to be effective for treatment of stage 4 ROP. In patients with temporal side retinal detachment only, segmental scleral buckling provides adequate treatment for stage 4 ROP.
TL;DR: This new laser trabeculoplasty has shown reasonable efficacy and safety on a limited number of eyes over a one year duration.
Abstract: ■ BACKGROUND AND OBJECTIVE: To investigate clinical efficacy and safety of a new laser treatment of open angle glaucoma that targets pigmented cells in the trabecular meshwork for disruption. ■ MATERIALS AND METHODS: The 16 eyes of chronic open angle glaucoma patients were treated in the method similar to argon laser trabeculoplasty using Q-switched, frquency-doubled Nd:YAG laser (523 nm). The treatment results were followed and analyzed for a one-year period. ■ RESULTS: Mean intraocular pressure reduction of 3.81 mm Hg (15%) at 3 months, 3.94 mm Hg (16.1%) at 6 months, and 4.93 mm Hg (20.2%) at 12 months from the baseline were obtained. Slightly greater reductions were seen in the responder group that consisted of eyes showing 3 mm Hg or greater reduction. Adverse reactions were minimal and not significant. ■ CONCLUSION: This new laser trabeculoplasty has shown reasonable efficacy and safety on a limited number of eyes over a one year duration.
TL;DR: Procedures that combine PPV for MH with cataract extraction and lens implantation decrease the need for future ophthalmic surgery, allow for clearer intraoperative visualization, and facilitate visual rehabilitation.
Abstract: ■ BACKGROUND AND OBJECTIVE: To evaluate the safety and efficacy of cataract extraction and lens implantation at the time of pars plana vitrectomy (PPV) for macular hole (MH) repair. ■ MATERIALS AND METHODS: A retrospective study was conducted of 21 eyes that had PPV for MH combined with cataract extraction and lens implantation. Visual acuities (VA) were followed and complications noted. ■ RESULTS: Of 21 eyes, successful anatomic closure was achieved in 16 (76.2%), and 13 (62.0%) improved in VA by at least 2 Snellen lines. Few complications occurred. ■ CONCLUSION: Procedures that combine PPV for MH with cataract extraction and lens implantation decrease the need for future ophthalmic surgery, allow for clearer intraoperative visualization, and facilitate visual rehabilitation. This combined procedure is a relatively safe and effective alternative to separate pars plana and cataract surgeries.
TL;DR: The disparity between the standard OCT image format and proportion-corrected images emphasizes the need for quantitative rather than qualitative evaluation of retinal dimensions and internal reflectance.
Abstract: BACKGROUND AND OBJECTIVE: The commercially available optical coherence tomography (OCT) scanner displays images in a pre-set window regardless of the projected scan length on the retinal surface. The aim of this study was to demonstrate the true dimensions of proportion-corrected OCT images and the additional information present in grayscale images. MATERIALS AND METHODS: OCT raw data were exported to an IBM-compatible PC and processed to show grayscale and proportion-corrected images using an automated software of our own design. RESULTS: Eyes with cystoid macular edema and retinal pigment detachment were analyzed. Grayscale images showed a finer gradation of signal reflectance. Scan lengths of 2, 4, 6, and 8 mm on the retinal surface showed different qualitative appearances using proportion-corrected software from the printed or on-screen images. CONCLUSIONS: Grayscale OCT images can be used to demonstrate additional information not present in false-color images. The disparity between the standard OCT image format and proportion-corrected images emphasizes the need for quantitative rather than qualitative evaluation of retinal dimensions and internal reflectance.
TL;DR: A case of combined harmartoma of the retina and retinal pigment epithelium in a 6-year-old child is reported as the presenting sign of neurofibromatosis-1, and she continues to be observed for further systemic manifestations of this disease.
Abstract: The authors report a case of combined harmartoma of the retina and retinal pigment epithelium in a 6-year-old child as the presenting sign of neurofibromatosis-1. The patient was followed closely for three years but received no treatment. Observation over these years revealed no significant change in the patient's visual acuity. A referral to the University of California San Francisco (UCSF) Neurofibromatosis Clinic resulted in a diagnosis of neurofibromatosis (NF)-1, and she continues to be observed for further systemic manifestations of this disease. Combined hamartoma of the retina and retinal pigment epithelimicrom, a rare and benign tumor, can be easily mistaken for malignant processes such as retinoblastoma or choroidal melanoma. Ophthalmologists should also be aware of the association with neurofibromatosis and consider this diagnosis when such retinal findings are observed in a child.
TL;DR: LASIK procedure seems to be an effective technique to correct refractive error after successful penetrating keratoplasty, and best corrected visual acuity for all patients.
Abstract: ■ OBJECTIVE: Refractive errors may invalidate the good results of penetrating keratoplasty (PK). The Authors evaluate the effectiveness of excimer laser in situ keratomileusis (LASIK) in the correction of refractive error after PK. ■ MATERIALS AND METHODS: Four patients, a 26-year-old woman, a 54-year-old man, a 19-year-old man, and a 51-year-old woman, showed refractive errors: -11 = -4.5 x 85°; -8, -4.5 = -11 x 95°; and -4.5 = -4 x = 120°, with a clear graft at least 20 months after penetrating keratoplasty secondary to keratoconus. However, they underwent the LASIK procedure with a nasal-hinged flap of 160 μm. No sutures were placed. ■ RESULTS: At follow-up, 24, 18, 12, and 12 months, respectively, the graft remained clear and the endothelial cells were unchanged. The uncorrected visual acuities were 20/50, 20/25, 20/50, and 20/25, respectively with an unchanged best corrected visual acuity (20/20) for all patients. No significant complications were observed. ■ CONCLUSIONS: LASIK procedure seems to be an effective technique to correct refractive error after successful penetrating keratoplasty.
TL;DR: Irregular astigmatism, particularly decentration component, increases significantly after trabeculectomy, but returns to the preoperative level 12 months after surgery.
Abstract: ■ OBJECTIVE: To examine irregular astigmatism following trabeculectomy using Fourier analysis of videokeratography data. ■ PATIENTS AND METHODS: Forty eyes of 40 glaucoma patients, undergoing primary trabeculectomy, underwent videokeratographic examinations preoperatively, and at 2 weeks and 1, 3, 6, and 12 months postoperatively. The dioptric data of the central cornea were decomposed into spherical, regular astigmatic, and irregular astigmatic (decentration and higher-order irregularity) components using Fourier analysis. ■ RESULTS: The mean spherical equivalent did not change throughout the observation period. The regular astigmatic component from 2 weeks to 6 months postoperatively was greater than the preoperative diopter, but the increase was not significant. In contrast, the decentration component increased significantly after surgery, but returned to the preoperative level by 12 months. The higher-order irregularity component also presented a transient increase postoperatively. ■ CONCLUSIONS: Irregular astigmatism, particularly decentration component, increases significantly after trabeculectomy, but returns to the preoperative level 12 months after surgery.
TL;DR: Laser photocoagulation in those diabetic eyes with diffuse diabetic macular edema and proliferative diabetic retinopathy can be completed in less number of treatment sessions with this method, compared to conventional treatment techniques.
Abstract: ■ PURPOSE: To determine the effectiveness of combined macular modified grid and peripheral panretinal photocoagulation in diabetic eyes with both macular edema and proliferative retinopathy. ■ MATERIAL AND METHODS: We evaluated 52 eyes with diffuse diabetic macular edema and proliferative diabetic retinopathy. Treatment was performed in two sessions consisting of initial modified grid to the macula and panretinal photocoagulation to the inferior half of the peripheral retina, followed 2 to 4 weeks later by panretinal photocoagulation to the superior half. ■ RESULTS: At one year, visual acuity was improved in 8%, stable in 79%, and worse in 13%. At two years, visual acuity was improved in 4%, stable in 72%, and worse in 24%. Macular edema resolved in 43 of 46 eyes (93%), and proliferative retinopathy was reduced in 25 of 29 eyes (86%) at last examination. ■ CONCLUSION: Combined macular modified grid and peripheral panretinal photocoagulation is an effective treatment approach in diabetic eyes with both macular edema and proliferative retinopathy. Laser photocoagulation in those diabetic eyes with diffuse diabetic macular edema and proliferative diabetic retinopathy can be completed in less number of treatment sessions with this method, compared to conventional treatment techniques.
TL;DR: One drop of 0.2% brimonidine instilled 1 hour preoperatively and immediately after capsulotomy was found to be efficacious and safe in preventing IOP elevations that frequently follow Nd:YAG laser posterior Capsulotomy.
Abstract: ■ BACKGROUND AND OBJECTIVE: To determine the prophylactic effect of 0.2% brimonidine in reducing the elevated intraocular pressure (IOP) in patients undergoing Nd:YAG laser posterior capsulotomy. ■ PATIENTS AND METHODS: The 81 patients (81 eyes), who underwent Nd:YAG laser posterior capsulotomy, were allocated to two treatment groups. One drop of 0.2% brimonidine or vehicle was instilled 1 hour preoperatively and one drop immediately after capsulotomy. IOPs were measured preoperatively and 1, 2, 3, and 24 hours postoperatively. ■ RESULTS: Intraocular pressure decreased from the baseline in the brimonidine group by the third postoperative hour (P<0.05), while the vehicle group exhibited an increase. Intraocular pressure elevations of 5 mm Hg or greater occurred in 7.3% (3/41) in the brimonidine group compared to 20.0% (8/40) in the vehicle group. IOP elevations of 10 mm Hg or greater occurred in 2.4% (1/41) in the brimonidine group compared to 7.5% (3/40) in the vehicle group. ■ CONCLUSIONS: One drop of 0.2% brimonidine instilled 1 hour preoperatively and immediately after capsulotomy was found to be efficacious and safe in preventing IOP elevations that frequently follow Nd:YAG laser posterior capsulotomy.