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Background: A case of exudative macroaneurysms in unilateral Eales' disease is reported. 'Eales disease' is an idiopathic bilateral occlusive periphlebitis with neovascularisation and mostly presents with vitreous hemorrhage., Case: A 30 year old male presented with diminution of vision in left eye (6/36) for 1 month. Slit Lamp examination of both eyes revealed normal anterior segment. Fundus examination of left eye with + 90 D lens revealed reddish lesions at the macula with surrounding circinate exudation. On peripheral examination hemorrhages were seen along with vasculitis in the superotemporal quadrant.The right eye fundus was normal.All laboratory investigations were found within normal limits., Conclusion: Eales' disease is mostly a bilateral condition but this case is rare as there is uniocular involvement with exudative macroaneurysms.Laser therapy was instituted which was effective in management of this condition with restoration of normal visual acuity.There was no relapse on follow up for 2 years., (© NEPjOPH.)

The development of anti-vascular endothelial growth factor (VEGF) molecules has expanded the range of available treatment options for many ocular diseases, including neovascular glaucoma (NVG). A number of studies have explored the use of anti-VEGF agents as stand-alone or adjunctive treatment for NVG. Although no large, prospective, randomized trials have been performed to date, the growing body of knowledge suggests that anti-VEGF agents are effective at reversing iris and angle neovascularization and lowering intraocular pressure in patients with NVG. Response to a single injection is typically temporary; therefore, laser or incisional surgery is still necessary in most cases. Future research is needed to determine the optimal agent, dose, route of administration, and timing of treatment either as monotherapy or coupled with other medical and/or surgical interventions.

Background: The progression of laser technology in neurosurgery has been limited by the poor maneuverability of traditional line-of-sight carbon dioxide (CO2) lasers and the propensity of other laser energies to cause collateral thermal injury to adjacent neural structures. The advent of a dielectric omnidirectional reflector and the subsequent development of phototonic bandgap fibers (PBF) have transformed the CO2 laser into a low-profile instrument with considerable dexterity and many potential new neurosurgical applications., Case Description: A 48-year-old woman presented with a large mass in the left lateral ventricle that was first diagnosed>20 years ago. The patient was asymptomatic until 1 month before presentation, when she began to experience progressive memory loss and neurocognitive decline., Results: The hand-held CO2 laser was used to debulk the tumor. The CO2 laser vaporized neoplastic cellular material and simultaneously cauterized microvascular structures., Conclusions: The CO2 laser was exceptionally useful in the resection of this long-standing and extremely calcified, yet vascular mass. A review of the evolution of laser technology applications in neurosurgery is presented, with a specific focus on the innovations that led to the development of the new PBF CO2 laser. This new technology may be advantageous in tumor surgery, particularly in the resection of long-standing calcified and vascular tumors that are not amendable to traditional surgical techniques., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: To investigate the possible roles of retinal photoreceptors in macular oedema and retinal angiogenesis with particular reference to the mode of action of laser therapy., Methods: (i) Studies in rats made hypoxic for 2 h by administering an oxygen/nitrogen mixture of reduced oxygen content, and growth factors determined by RT-PCR, western blotting, and immunohistochemistry. Assessment of blood-retinal barrier integrity using fluorescent and electron-dense tracers. (ii) Studies in pigs with one retina made hypoxic by selective embolisation of the retinal capillary circulation with fluorescent microspheres. (iii) Assessment of laser therapy in selected cases of retinal neovascularisation indicating a role for photoreceptors., Results: In the hypoxic retina, angiogenic and vascular permeability factors such as vascular endothelial growth factor (VEGF), nitric oxide synthases (NOSs), and insulin-like growth factor-1 are upregulated in retinal astrocytes and Müller cells but are also present in large amount in the photoreceptors. Hypoxia-inducible factor-1 (HIF-1) is upregulated in retinal glial cells but not in the photoreceptors, suggesting that growth factors in the photoreceptors may not have been generated there. The tracer dye, rhodium isothiocyanate, leaking from an abnormally permeable inner blood-retinal barrier in the hypoxic retina accumulates in the photoreceptors., Conclusions: The results indicate that laser treatment of macular oedema or retinal neovascularisation may obtain its effect not only by improving oxygen availability in the inner retina, but also by reducing the load of angiogenic/permeability factors that accumulate in the photoreceptors in hypoxic/ischaemic conditions.

Objective: To describe the comparative impact of current and preventive treatments on incidence of choroidal neovascularization (CNV) and severe vision loss in patients with bilateral soft drusen (BSD)., Design: Stochastic model., Setting: US population., Patients: Prevalence cohort of white patients 43 years or older with BSD., Interventions: Application of prophylaxis of 10% to 50% efficacy to 1 or both eyes of patients with BSD, application of laser photocoagulation to eligible CNV lesions, or both., Main Outcome Measures: Proportion of patients with BSD after 10 years with unilateral and bilateral CNV and resultant unilateral and bilateral vision loss to visual acuity of 20/200 or worse., Results: The natural history of patients with BSD generated by the model shows that 12.40% of these patients develop either unilateral or bilateral CNV within 10 years of their entry into the BSD prevalence cohort. Bilateral disease occurs in 3.86% of patients with BSD within 10 years. The proportion of patients with BSD becoming legally blind from CNV within 10 years is 2.54% if no treatment is performed. Current laser treatment for CNV decreases the proportion with legal blindness within 10 years to 2.24%. The addition of a preventive treatment of 10% efficacy applied bilaterally to the current laser treatment regimen decreases the proportion with legal blindness to 1.86%; a 25% effective preventive treatment decreases it to 1.34%. Comparatively, preventive treatment of 10% and 25% efficacy given to the fellow eye only after the first eye has developed CNV decreases the proportion of legally blind patients at 10 years only to 2.06% and 1.77%, respectively. All outcomes vary with sex and age at entry into the BSD cohort., Conclusions: Patients with BSD face a 12.40% risk of developing CNV within 10 years. The addition of even a modest (10% effective) bilateral preventive treatment to the current regimen for CNV would more than double the prevention of legal blindness in the BSD population relative to current laser treatment; a preventive treatment of 33% efficacy more than halves the rate of legal blindness caused by CNV. Preventive treatment given to the fellow eye only after the first develops CNV has substantially less impact.

Background: Lacquer cracks are breaks in the retinal pigment epithelial-Bruch's membrane-choriocapillaris complex and are manifestations of pathologic myopia. Progressive posterior segment elongation, uveal scleral thinning, and retinal pigment epithelial degeneration are thought to create a predisposition for crack formation in these eyes. In turn, choroidal neovascularization (CNV) may develop within the cracks to produce disciform scarring of the macula. This study examined lacquer cracks as a possible consequence of laser photocoagulation of CNV., Methods: From the files of two retinal referral practices, five patients were located in whom lacquer cracks developed or expanded after laser photocoagulation for macular CNV in pathologic myopia. The mean age of the patients was 54.8 years. Four patients were treated with krypton red laser and one with an argon laser. Laser settings were available for only one of the patients., Results: After laser photocoagulation, lacquer cracks were noted to expand in one or two directions from the laser scar between 10 days and 3 months of the treatment. The cracks also served as a pathway for progressive or recurrent neovascularization., Conclusions: Although lacquer cracks occur spontaneously in pathologic myopia, expansion, elongation, or simple development of a crack may occur as a result of laser photocoagulation of CNV. The new cracks also serve as a potential risk for recurrent neovascularization. This potential adverse complication should be considered in the management of CNV in pathologic myopia with laser treatment.

Purpose: To determine the effectiveness of Nd:YAG laser membranectomy for reopening blocked glaucoma tube shunts and maintaining the patency over time., Methods: We reviewed retrospectively the records of 13 patients (13 eyes) who, during the period January 1990 through June 1996, underwent Nd:YAG laser membranectomy in an attempt to reopen a blocked glaucoma tube shunt. Intraocular pressure and tube patency were evaluated at each follow-up visit., Results: Nd:YAG laser membranectomy effectively opened the blocked glaucoma tube shunts in 11 (84.6%) of 13 eyes. Two tubes could not be reopened. Reblockage occurred in seven eyes (53.8%) within the first 11 weeks; four tubes (30.8%) remained patent through follow-up periods of 39, 82, 106, and 169 weeks. Postlaser complications were moderate anterior chamber reaction in four eyes (30.8%), hyphema in two eyes (15.4%), corneal edema in two eyes (15.4%), pressure spike in one eye (7.7%), and shallow anterior chamber in one eye (7.7%)., Conclusions: Nd:YAG laser membranectomy is effective in reopening blocked glaucoma tube shunts but is associated with a relatively high rate of subsequent reblockage in the initially successful cases.

Purpose: To treat a patient who had a choroidal neovascular membrane after laser-induced chorioretinal anastomosis for nonischemic central retinal vein occlusion., Methods: A 70-year-old man underwent successful formation of a chorioretinal anastomosis for nonischemic central retinal vein occlusion. He subsequently developed a choroidal neovascular membrane at the site of the chorioretinal anastomosis., Results: The choroidal neovascular membrane at the site of the chorioretinal anastomosis was treated successfully with argon laser photocoagulation. The anastomosis remained functional., Conclusion: We recommend that patients who have undergone laser-induced chorioretinal anastomosis for nonischemic central retinal vein occlusion be followed up closely for choroidal neovascular membrane formation.

Objective: To determine whether argon green laser (AGL) or krypton red laser (KRL) is superior for the treatment of well-defined extrafoveal choroidal neovascularization (CNV) in patients with age-related macular degeneration (AMD) after 3 years of follow-up., Design: Multicentre randomized clinical trial., Setting: University-based referral practices in Canada., Participants: Among 210 patients selected by ophthalmologists at 13 participating centres there were 191 eligible patients aged 50 years or more with angiographically proven CNV whose posterior edge was 200 to 2500 microns from the foveal avascular zone. Other inclusion criteria included the presence of drusen in either eye, a best corrected visual acuity in the study eye of at least 35 letters on the Early Treatment Diabetic Retinopathy Study chart (equivalent of 20/200 or better on the Snellen chart) and no prior photocoagulation in the study eye. The patients were randomly assigned to receive either AGL (96 patients) or KRL (95 patients) treatment., Interventions: Treatment with 200-microns spots of 0.2 to 0.5 seconds' exposure to produce a homogeneous grey white lesion that completely covered the CNV., Outcome Measures: Change from baseline in visual acuity at 1, 2 and 3 years (primary measure), development of persistent or recurrent CNV (secondary measure)., Results: There were no significant differences between the treatment groups in drop-out rates. No significant differences were found between the two groups in loss of visual acuity or angiographic evidence of persistent or recurrent CNV., Conclusion: KRL is no better than AGL in preserving vision and preventing loss of visual acuity in patients with AMD with well-defined extrafoveal CNV followed for 3 years.

The introduction of laser photocoagulation for the treatment of macular disease has enabled many patients to retain visual acuity and retard additional deterioration of vision. Treatable maculopathy can occur as the result of choroidal neovascular development, idiopathic central serous choroidopathy, and retinal vascular disease. Variations in the treatment of these maculopathies include type of laser used, spot size, duration of treatment, burn pattern, and intensity of the burn. The cause of the maculopathy determines the type of laser photocoagulation that is most appropriate. While some forms of treatment leave characteristic scars, others leave hardly a trace. Use of fluorescein angiography, and in some cases indocyanine green angiography, is essential in the determination of the appropriate laser treatment modality.

The aim of this study was to compare the efficacy of various dye laser wavelengths in different forms of retinopathies. The study material consisted of 292 eyes of 210 diabetic retinopathy patients treated with dye laser photocoagulation between 1990 and 1992. All the patients were followed for at least 6 months after photocoagulation. Non-proliferative changes (maculopathy and/or preproliferative retinopathy) were present in 135 (46.3%) and proliferative retinopathy in 157 (53.7%) of the eyes undergoing photocoagulation. Of the 157 eyes with proliferative retinopathy, 60 (20.5%) had disc neovascularization, 71 (24.3%) had retinal neovascularization and 26 (8.9%) had retinitis proliferans. Yellow dye laser (580 nm) was applied in 92 (31.5%) eyes, red dye laser (630 nm) in 120 (41.1%) eyes and both yellow and red dye lasers in 80 (27.4%) eyes. There was no significant difference between the different wavelength groups with regard to visual acuity changes before and after treatment (p < 0.01). Overall, the visual acuity was maintained in 56.2% and improved in 25.0% of the eyes. After panretinal photocoagulation, disc neovascularization regressed partially or completely in 47 (78.3%) of the eyes. There was no significant difference among the various laser wavelengths with regard to treatment efficacy judged by the disappearance or regression of disc neovascularization (p < 0.01). All retinal neovascularizations regressed completely with laser treatment, but in 7 eyes (9.9%) new retinal neovascularizations in previously untreated areas developed. Dye laser has not resulted in any complications. It requires lower power settings compared to argon laser and thus facilitates photocoagulation. Another advantage of dye laser is the ability to use yellow and red wavelengths sequentially.

In contrast to focal laser treatment of large subfoveal neovascular membranes, perifoveal laser treatment sparing the central avascular zone can partially retain central macular function in some cases. The anatomical and functional outcome of this technique was analysed in 26 patients with large subfoveal neovascular membranes (0.6 to 3.0 disc diameter) secondary to age-related macular degeneration (24 cases) or presumed ocular histoplasmosis syndrome (two cases). Patients were followed for six to 39 months. Out of 26 patients 21 had a stable dry scar at the last follow-up examination. Central fixation was retained postoperatively in nine out of 13 patients with central fixation prior to laser treatment. Visual acuity was maintained or improved in 19 out of 26 treated eyes. Statpack analysis (Humphrey Field Analyser) of the long-term results of patients with central fixation indicated an increase in the depth of their relative central scotoma not only immediately after laser treatment but also in the first and second postoperative years. This increasing depth of central scotoma subsequently led to a shift of central fixation to a paracentral area in four out of nine patients six to nine months after treatment. Indocyanine-green angiography showed remaining subfoveal choroidal vasculature corresponding to the area of central fixation, as found in fundus microperimetry by scanning laser ophthalmoscope. Perifoveal laser treatment seems to be effective in maintaining some initial macular function for a limited time in selected patients suffering from subfoveal neovascular membranes.

The authors report four patients who were treated with krypton red laser photocoagulation for neovascular membrane in the papillomacular bundle. In each patient, from 1 to 7 days following photocoagulation, there was a transient delay in filling of the choroid in a localized area beyond the treatment site. No patient suffered permanent visual loss as a result of this complication. Each patient regained normal choroidal filling (except for the treatment site) within two to four weeks. This angiographic observation may be explained by the increased uptake of the krypton red wavelength in the deep choroid.

During the past 2 years, 44 patients (71 eyes) had pan-retinal photocoagulation by argon gas laser for proliferative diabetic retinopathy. All except 9 eyes benefitted from the treatment, peripheral and disc vessels showing regression. Many of the patients needed, or will need, further laser treatment. The main complications of treatment were slight or moderate constriction of the visual field, poor night vision and macular oedema.

Established neovascular glaucoma in the presence of clear media can be treated by panphotocoagulation followed by drainage surgery. Three cases are described, and the advantages of this procedure as opposed to others available are discussed. Photocoagulation must be performed early before the development of opaque ocular media obscures the retina.

A 78-year-old man with perifoveal subretinal neovascularization originally treated with krypton red laser was re-treated. An attempt was made to produce a "chalky white" burn at the site of the neovascular frond. Immediately after a burn, a brisk choroidal haemorrhage followed, apparently from a ruptured choroidal vessel. Bleeding occurred subretinally and into the vitreous, blinding the patient. While the krypton red laser carries advantages over the argon laser in the treatment of subretinal neovascular fronds, this case indicates that hard burns with the krypton laser carry a risk of massive subretinal haemorrhage.

The Ocular Histoplasmosis Study (OHS) is a multicenter controlled clinical trial designed to determine whether argon laser photocoagulation is useful in preventing severe visual acuity loss in eyes with choroidal neovascular membranes (NVMs) 200 to 2,500 microns from the center of the foveal avascular zone and evidence of ocular histoplasmosis. Eligible patients were assigned to photocoagulation (n = 124) or to observation only (n = 121) groups. Recruitment of patients who have extrafoveal NVMs for the OHS has been terminated because more untreated eyes than treated eyes had experienced severe visual acuity loss. At the most recent follow-up visit (median follow-up, 18 months), 34.2% (39/114) of untreated eyes v 9.4% (11/117) of treated eyes had lost six or more lines of visual acuity from the baseline level. The superiority of argon laser photocoagulation was evident in all subgroups and at every point in follow-up time, indicating that patients who meet the eligibility criteria will benefit from treatment. Follow-up of all patients continues in order to assess long-term results of treatment.

We simulated the treatment of recurrent choroidal neovascular membranes (CNVM) by applying two courses of laser treatment to monkey retinas. Argon green, argon blue-green, and krypton red lasers (KRLs) were used in juxtafoveal, papillomacular bundle, and nonmacular areas. The effects were examined clinically and histopathologically. Results of once-treated control eyes were consistent with those of previous studies. Repeat treatment, however, resulted in full-thickness retinal destruction or necrosis with all laser modalities and in all fundus locations. These results are consistent with the absorptive characteristics of xanthophyll and melanin and suggest only limited advantages to the KRL when treatment of recurrent CNVM is performed in a previously treated area of the fundus. However, treatment of recurrent CNVM is still probably most successful with a KRL, because recurrent CNVM is usually at a border of a photocoagulation scar, where the retina is still untreated, and because histologic studies have demonstrated inner retinal sparing with a KRL in juxtafoveal areas.

Fifteen consecutive eyes with central retinal vein occlusion (CRVO) and extensive capillary non-perfusion were treated by panretinal photocoagulation using argon laser. Of these eyes six had chronic glaucoma and one had acute angle-closure glaucoma when first seen. One developed neovascular glaucoma before treatment. After photocoagulation iris new vessels appeared in two eyes with pre-existing glaucoma. In one case the new vessels later regressed without further treatment. The prevalence of neovascular glaucoma was considerably less than has been reported in untreated eyes with ischaemic-type CRVO. Poor dilatation of the pupil due to pre-existing glaucoma, cataract and/or massive retinal oedema put a limit on the extent of treatment.

Relative merits of different laser wavelengths for macular photocoagulation are analyzed in terms of light scattering and light absorption in hemoglobin, melanin, and macular xanthophyll. Disadvantages of inner retinal damage in the macula caused by the blue-green argon photocoagulators in standard clinical use are discussed, along with advantages of argon green and krypton yellow light. Results of treatment of subretinal neovascularization in disciform macular degeneration are presented. A repetitive treatment, close follow-up protocol was employed with the objectives of closing neovasculature and preserving central visual field. In 74 successive patients treated with monochromatic argon green radiation, neovasculature was closed in 93%, central visual field loss was reduced or stabilized in 76%, and visual acuity was improved or stabilized in 70%. Results were analyzed in terms of location and size of the neovascular membrane, and it was found that best results were obtained with neovascularization farther than 600 microns from the foveola and smaller than 2 mm2. In 17 patients with neovascular membranes more than 600 microns from the foveola, neovasculature was closed in 100%, central visual field loss was reduced or stabilized in 94%, and visual acuity was improved or stabilized in 88%. Similar results were obtained with monochromatic krypton yellow radiation.

The authors reviewed four cases of iatrogenic subretinal neovascularization after focal argon green photocoagulation for clinically significant diabetic macular edema. An inappropriate combination of small spot size with a high-power setting is the common feature in each case of iatrogenic subretinal neovascularization. Close follow-up with fluorescein angiography is used to identify iatrogenic subretinal neovascularization at an early, treatable stage. All four patients responded favorably to laser photocoagulation of the subretinal neovascular membrane.

In a retrospective study, 2688 eyes treated with xenon arc photocoagulation which would have qualified for inclusion in the Diabetic Retinopathy Study (DRS) were reviewed in the format of the DRS. When comparable risk groups were compared, the results of treatment were even more favorable than reported in the DRS without the severe complications attributed to xenon treatment in the DRS. A critical analysis of the DRS gives clues for the greater amount of visual loss found with xenon than argon in the DRS. Since these complications may be avoidable in some cases, and since xenon has been shown to be at least as effective as argon, it should continue to be used in the treatment of proliferative diabetic retinopathy.

Nearly 90% of severe visual loss among patients with senile macular degeneration can be ascribed to the neovascular form of the disease. The Senile Macular Degeneration Study demonstrated that argon laser photocoagulation can reduce the risk of severe visual loss by more than 60% among patients with choroidal new vessel membranes 200 microns or greater from the center of the foveal avascular zone (FAZ). The Krypton Photocoagulation Study, also supported by the National Eye Institute, is evaluating whether krypton red laser photocoagulation can reduce the risk of visual loss in SMD patients with new vessels within 200 microns of the center of the FAZ.

The use of krypton red laser photocoagulation (KRLPC) to treat subretinal neovascular membranes (SRNVM) is increasing. The complications of this treatment in a large series of patients have not been reported. Over a 15-month period, 195 patients had KRLPC to SRNVM of the following etiologies: senile macular degeneration (151), presumed ocular histoplasmosis (33), miscellaneous (11). Fourteen patients had the following complications attributable to KRLPC: choroidal hemorrhage (9), retinal pigment epithelial tears (3), choroidal ischemia (1) and choroidal folds (1). The visually significant complication rate was 3.6%. Proper patient selection and treatment technique may decrease the risk of complications.

During the past 18 months, 23 cases of advanced neovascular glaucoma, unresponsive to medical therapy, have been treated by a trabeculostomy procedure using a carbon dioxide laser. This procedure entails surgical entry into the anterior chamber from beneath either a conjunctival or a scleral flap in such a way as to completely cauterize any neovascular tissue in the iridocorneal angle and to permit adequate drainage of the aqueous fluid from the anterior chamber to the periocular space. The average intraocular pressure, prior to carbon dioxide laser trabeculostomy was 54 mm Hg and these pressures were lowered below 18 mm Hg in over 57% of the cases followed for longer than six months post-laser therapy. Treatment was considered a failure in 26% of the cases where the intraocular pressure was not lowered substantially, and 17% of the treated eyes sustained a pressure decrease to within the 25 to 35 mm Hg range. Carbon dioxide laser trabeculostomy or trabeculo-sclerostomy provides a new method of lowering the intraocular pressure in severe cases of neovascular glaucoma without the hazard of intraocular hemorrhage, common with other filtration procedures. These procedures have proved satisfactory in alleviating the high pressures of neovascular glaucoma in a relatively large proportion of the patients treated. If the eye is grossly hyperemic and irritated because of the high intraocular pressure and the deteriorated condition of the eye, it is suggested that the carbon dioxide laser trabeculostomy procedure with a scleral flap be performed with an implanted seton as the procedure of choice. If the eye is relatively quiet and has some visual reserve but an exceedingly high and intractable intraocular pressure, it is advisable to use either the carbon dioxide laser trabeculostomy procedure or the carbon dioxide laser trabeculo-sclerostomy operation as described. These procedures are being further refined, but the results of this investigation suggest that these procedures can be utilized judiciously, and should prove useful, particularly in those eyes with advanced neovascular glaucoma with useful vision still remaining.

The destruction of senile neovascular membranes in the central avascular region of the macula using argon laser is difficult and associated with complications. Yellow pigment in this region absorbs the blue component of the conventional argon laser radiation. In this study, we compared laser of different wavelenghts: red krypton and green argon. Light and electron microscopic studies on non-human primates were performed at one hour and three weeks following laser burns. With the red krypton laser maximum damage was seen at the level of choriocapillaris and the choroïd, although the pigment epithelium was also destroyed. With the green argon laser the maximum absorption occurred at the level of the pigment epithelium. A clinical and angiographic study showed that the destruction of juxtafoveal neovascular membranes by both these lasers was possible after one or several treatment sessions. After an average follow-up period of 45 months, visual acuity was stable or improved in 10 out 17 eyes treated with the green argon laser and in 27 out of 53 eyes treated with the red krypton laser. Our results suggest that the red krypton laser offers a better alternative for the treatment of neovascular membranes located near the foveola since less unnecessary damage is induced. Outside the xanthophyllic area there is no major difference between the different wavelengths.

Eight patients with active extrafoveal choroidal neovascular membranes related to angioid streaks were studied. One eye of each of four patients was treated with argon laser. Two patients received bilateral treatment. Four patients received multiple treatments at different times for recurrence of neovascular membranes. Two patients were not treated. The visual acuity of the treated eyes remained the same or improved posttreatment, with one exception. The majority of untreated eyes lost vision. The vast majority of the treated eyes showed a marked improvement in central visual field posttreatment, whereas the untreated eyes remained the same or lost considerably more central visual field. In one to four years after treatment, recurrences of the neovascular membranes occurred in four of the treated eyes demonstrating that these cases must be followed indefinitely. Carefully selected cases appear to benefit from complete obliteration of choroidal neovascularization by argon laser photocoagulation.

Clinical research utilizing the yellow, orange, and red wavelengths of the dye laser (Rhodamine 6G and MD-631) appears to have considerable promise and may demonstrate that the liquid organic dye laser is the laser of choice for photocoagulation of many types of ocular defects. The effectiveness of the dye laser as a photocoagulation source is due to the trans-spectral availability of relatively high output power wavelengths. Therefore, a target tissue can be selectively coagulated with minimal laser energy transmitted through the refractive media and minimal damage to nearby normal tissues. The dye laser, as a photocoagulation system, should prove valuable in the therapy of many ocular diseases.

A retrospective study was conducted covering a total of 229 patients with choroidal neovascularizations in age-related maculopathy. Of these patients, 81 had been treated by photocoagulation and 148 had been followed up without treatment. After four years' follow-up of statistically comparable groups the photocoagulation group showed significantly better results than the control group with regard to both final visual acuity (p = 0.01) as well as changes between initial and final visual acuity (p = 0.03). This therapeutic effect of photocoagulation treatment in extrafoveolar choroidal neovascularization was only observed in patients followed up for a maximum of six years (p = 007), while in patients who had been followed up for longer periods of time similar visual results between the coagulation and control groups were found (p = 0.4).

The visual outcome of 20 eyes of 20 patients with peripapillary subretinal neovascular membranes (SRNVM) treated with krypton red laser photocoagulation (KRLP) was studied. Complete obliteration of the SRNVM was achieved in all eyes in the study. In 18 of 20 patients, the visual acuity improved or remained the same during an average follow-up of 9.9 months. There were no treatment-related complications. The efficacy of KRLP in the management of patients with peripapillary SRNVM is discussed.

Between 1982 and 1985, cataract extraction was performed on 144 eyes of 122 diabetics, and the early and late complications of the operation were recorded. There was seldom any intraoperative hemorrhaging or any postoperative anterior chamber hemorrhaging. On the first day after the operation, increased IOP was measured more frequently in diabetic patients than in those without diabetes. Diabetic retinopathy deteriorated in 12 eyes, while hemorrhaging glaucomas occurred in 5 eyes.

The authors present a randomized study of 27 eyes affected by pathological myopia with macular subretinal neovascularization which were treated with a tunable dye laser. The effectiveness of three different wavelengths (577, 590 and 620 nm) in the direct treatment of subretinal neovascularizations was evaluated in 3 groups of 9 patients each. Statistical analysis of both visual and anatomical results did not show significant differences among the three wavelengths used.

Fifty eyes of patients with proliferative diabetic retinopathy were followed at frequent intervals to determine the rapidity and stability of retinopathy risk factor regression after argon laser panretinal photocoagulation. Retinopathy risk factors regress rapidly after laser photocoagulation. The incidence of eyes at high risk for severe visual loss (eyes with 3 or more retinopathy risk factors) decreased from 100% prior to treatment to 28% three weeks after treatment. The early response to treatment was a good prognostic indicator of longer term results. Seventy-two percent of eyes which improved from a high- to a low-risk category by three weeks continued to remain at low risk at six months. Sixty-four percent of eyes which failed to improve to a low-risk category by three weeks continued to remain at high risk at six months. The early response to laser panretinal ablation may be used to predict longer-term results.