This is to certify that the dissertation entitled, “A STUDY ON CLINICALOUTCOMES OF LASERPHOTOCOAGULATION FOR PREMATURERETINOPATHY” submitted by Dr.MALATHI.V.K, in partial fulfillment for the award of the degree of Master of Surgery in Ophthalmology by The Tamil nadu Dr.M.G.R.Medical University, Chennai is a bonafide record of the work done by her in the Regional Institute of Ophthalmology, Government Ophthalmic Hospital, Egmore, Chennai, during the academic year 2010-2013.
Despite of the advent of anti-VEGFs in treatment of DR, laserphotocoagulation still plays a vital role in management of DR and will continue to be a pivotal component for the next several years. 19 In the multicentre randomized clinical trial by the DRCR network it had been shown that over a two year period, focal/grid photocoagulation was more effective and had fewer side effects than 1-mg or 4-mg doses of preservative-free intravitreal triamcinolone for most patients with DME. The study supported the fact of focal/grid laserphotocoagulation being effective in the treatment of DME. 20 The results of the RESTORE study by Mitchell et al. 21 advocate a combined modality of treatment for DME in the form of ranibizumab with laserphotocoagulation. Excellent to good eyesight was reported by 50% of the patients who had taken a combined treatment (determined by the individual NEI VFQ-25 question pertaining to patient’s perception of eyesight post-treatment). The present study shows that laserphotocoagulation has a distinct role in maintaining a stable visual acuity in patients with DR. Improvement in CS is the maximum after focal laser in CSME due to the subsidence of macular edema. Majority of the patients demonstrate no change in the self reported visual disability after laser treatment (60.4%) while only a few patients experienced a worsening (3.8%).
characteristics (deferred treatment) developed. Methods A Markov model with a 30-year time horizon was developed, in which patients presenting with moderate NPDR could progress through all stages of DR (severe NPDR>early PDR>HR-PDR>severe PDR) to severe vision loss and blindness (and to death). A National Health Service and personal social services perspective was adopted. Transition probabilities were mainly derived from the Early Treatment Diabetic RetinopathyStudy. Health state utilities, costs and complications were based on information from the literature, supplemented by expert opinion. Costs and outcomes were discounted at 3.5%. Both deterministic and probabilistic sensitivity analyses were conducted. Results Administering PRP at the severe NPDR stage could be more effective and less costly than waiting until HR-PDR developed. Sensitivity analyses gave similar results, with early treatment continuing to dominate deferred treatment. The probabilistic sensitivity analysis suggests that at willingness-to-pay threshold of £20 – £30 000 per quality-adjusted life year, the probability of early treatment being cost-effective is 60%.
Treatment recommendations for the management of Asian patients with DME are largely based on studies performed outside the region, with limited data generated from the Asian population. 5 Recent evidence-based recommendations developed speci ﬁ cally for Asian coun- tries highlight the need to enhance physician understand- ing of the importance of early intensive treatment to help optimize patient outcomes. 5 While many Asian ophthal- mologists still consider laserphotocoagulation treatment as the mainstay treatment option, the latest recommenda- tions suggest early and intensive anti – VEGF therapy as a ﬁ rst-line treatment for patients with center-involving DME with vision loss. In the present study, comparable outcomes observed in the IVT-AFL 2q8 versus 2q4 groups may indicate that initial therapy for the ﬁ rst 5 months followed by a reduced frequency of treatment is feasible without compromising ef ﬁ cacy. The latest recommendations for clinical management of DME in Asia state that the choice of anti – VEGF agent treatment depends on baseline visual acuity. 5 Treatment guidelines highlight the Protocol T study, which demonstrated that in patients with poor baseline visual acuity who may present late, IVT-AFL may offer better results compared with alternative anti – VEGF treatment over 1 year. 9 Furthermore, a previous study conducted in Asia demon- strated that IVT-AFL was an ef ﬁ cacious treatment option for DME in Asian patients who were refractory to mono- clonal antibody-based anti – VEGF therapy. 10 The safety outcomes from the current study were consistent with the known safety pro ﬁ le of IVT-AFL in DME. 6 – 8 TEAEs were mild in intensity for most patients in the IVT-AFL groups. There were no cardiovascular events or deaths, which have previously been identi ﬁ ed as potentially associated with anti – VEGF therapy in patients with DME. 5
This study was performed to evaluate the functional and anatomic outcomes of focal macular laserphotocoagulation in eyes with non-center involved macular edema (non-CI ME). Forty-nine eyes of 43 patients with non-CI ME were included. Focal macular laserphotocoagulation was conducted on twenty- nine eyes of 25 patients, while 20 eyes of 18 patients with non-CI ME were followed without treatment and served as the control group. Data relating to best corrected visual acuity (BCVA; Early Treatment Diabetic RetinopathyStudy) and central subfield thickness (CST), inner zone thickness (IZT), outer zone thickness (OZT), and total macular volume (TMV) as determined by optical coherence tomography (OCT) were collected and compared between the groups. At 12 months, VA decreased by a mean of 0.4 letters in the treatment group and 3.3 letters in the control group (p=0.03). Gain in VA ≥5 letters was noted in 6 (21%) of the eyes in the treatment group versus 1 (5%) eye in the control group (p=0.12). At 12 months, average IZT decreased by 22.6 microns in the treatment group and increased by 10.9 microns in the control group (p<0.001). The treatment group revealed significant reduction in CST, average OZT, and TMV as compared to the control group at 12 months (all p<0.05).Generally, focal laserphotocoagulation may have more favourable visual outcomes in this specific group of diabetic patients than does observation. In addition, focal laser treatment provided better outcomes with improvement in OCT parameters as compared to the control group.
The donor twin may become severely anaemic; urine output diminishes, growth falters and their amniotic sac empties and shrinks (oligohydramnios). Such a fetus may ultimately become adhered to the membranes (“stuck twin”). Should it survive to birth, his or her lungs may not have developed adequately. At birth, a donor may appear small, malnourished and pale. In contrast, the recipient is at risk of blood volume overload. This fetus attempts to compensate by increasing urine output. Excessive urine production then distends their amniotic sac (polyhydramnios). At birth the recipient may appear large, swollen and red. Accumulation of amniotic fluid may cause uterine contractions, with pressure on the uterus and cervix triggering premature labour or pre- cipitating preterm premature rupture of the membranes.
A literature search was undertaken for cost-effective- ness studies of the use of PRP and/or anti-VEGF medication for patients with moderate or severe NPDR. However, we could not identify any appropriate studies. 5 Therefore, we developed a de novo Markov model in Microsoft Excel to assess the cost-effectiveness of early versus delayed PRP. The different clinical pathways for patients were obtained from information from the Early Treatment Diabetic RetinopathyStudy (ETDRS) 6 and from expert opinion. 5 The model starts with a hypothetical cohort of 1000 patients with diabetes with a starting age of 50 years presenting with moderate NPDR at an ophthalmology clinic. Fifty years was chosen for the starting age, as this was the mean age of patients with DR. 5 As DR is a bilateral disease, we have assumed that the model is a two-eye model and that the severity level is the same in each eye. The model assumes that people can progress through all
Spontaneous regression occurred in 69 babies (71.13%). Diode red 810 nanometer wavelength laser was used at strength of 250 milliwatts for 150 milliseconds and number of shots varied from 1500 to 2000 depending upon the area extent of retina involvement. Babies (8.24%) those diagnosed as aggressive posterior retinopathy of prematurity (APROP) were first treated with intravitreal anti Vascular endothelial growth factor(VEGF) Bevacizumab to reduce the dilatation and tortuosity of vessels at posterior pole followed by laserphotocoagulation after 1 week . Here the number of shots required was higher (ranging from 2500 to 3500 shots) than for any stage of ROP requiring treatment. Two babies (2.06%) with stage 4 plus disease underwent vitreoretinal surgery. The laser photocoagulated babies and babies who had undergone vitreoretinal surgery were followed first after 2 weeks and then at monthly intervals. All the laser photocoagulated babies showed signs of regression of ROP in subsequent visits and the disease became stable in babies who underwent surgery. The final outcomes of these babies were still under study as they are prone for complications of ROP like refractive error, amblyopia, glaucoma and retinal detachment which may develop later.
A total of 16 eyes of 15 subjects were enrolled for this pro- spective study. The mean age of patients was 42.2 ± 9.9 years with 12 males and three females. Mean duration of symp- toms was 11.45 ± 16.6 months (range 3 months to 4 years). Clinical characteristics of study subjects are shown in Table 1. The most common location of a leak in relation to the fovea was superonasal (15 leaks, 34%), inferonasal (13 leaks, 29%), superotemporal (10 leaks, 23%) and inferotemporal (7 leaks, 14%). Mean pretreatment BCVA and posttreatment BCVA at 2 months was 0.28 logMAR (71 ETDRS [Early Treatment Diabetic RetinopathyStudy] letter score, approxi- mately 20/40) and 0.17 logMAR (76.5 ETDRS letters score, approximately 20/30), respectively (P = 0.171).
In patients with diabetes, high blood HbA1c suggests poor blood sugar control, which might threaten tissue viability, which in turn theoretically makes the RNFL vulnerable to external insults, such as laser. However, this vulnerability did not translate into further damage to RNFL thickness post-laser treatment in our study. Poor diabetic control, as defined by HbA1c level, did not increase the risk of further RNFL changes immediately post-PRP. Interestingly, this association has never been highlighted in other studies and we believe that this should be further evaluated with more specific outcomes.
The Xinhua hospital has a major referral neonatal in- tensive care unit for premature infants with varying levels of ROP. Medical records of consecutive patients admitted for ROP screening between January 2012 and June 2016 were reviewed. Exclusion criteria were pres- ence of other associated pediatric retinopathies and sus- pected familial exudative vitreoretinopathy in preterm infants who showed a disease course not consistent with ROP or had a family history. A total of 1694 records with a diagnosis of ROP were identified. Thirty-three eyes of 17 infants received primary treatment for type 1 ROP after PMA of 40 weeks and 16 of these were followed up for > 6 months. Two infants who were diag- nosed with stage 4 or 5 ROP in one eye before treatment were excluded, as they were scheduled for a more ag- gressive treatment plan to monitor the lateral eye with
In the P100 latency analysis, one of the most diagnostic visual evoked potential parameters, P100 wave latency changes showed an increasing trend after laser therapy in the study groups so that after ﬁ rst, second and third laser therapy sessions, an approximate increase of 2.7%, 2.6% and 3.3% of the corresponding wave in latency was occurred, respectively. Also, the evaluation of the ampli- tudes and latencies of P100 component of PRVEP test in the pre-treatment and 1.5 months after the ﬁ nal treatment showed that the lower difference between the pre-treat- ment and the 1.5-month post-treatment period in the latency compared to the amplitude parameter. In fact, the amplitudes as well as latency following PRP recovered, but there was greater recovery with latency. This can be because of that in the clinical practice, latency delay and interocular differences in latency of the P100 wave are seen as more sensitive and reliable indicators of dysfunc- tion in the visual pathway than amplitude changes. 13
neovascularization process. We noticed clinical progression of neovascularization in one eye (10%) in the STM group. Although the eye with SNPDR developed a hemorrhage, no clinically detectable new lesions were seen, and even though we have treated this as a progression as per the definition in our study, we feel that, owing to lack of wide-field imaging, a neovascular complex in the far periphery could have been missed at diagnosis as well at further follow-ups or it could have been induced by posterior vitreous detachment. While resolution of neovascularization is the conventional treatment goal of panretinal laser for PDR, arrest and regression is the norm, and complete disappearance is rare with conventional photocoagulation and long-term anti-VEGF suppressive treatment. Echoing the findings of Luttrull et al, 8 eliminating
study population were SNPDR in 23(46%), VSNPDR in 16(32%) and PDR in 11(22%). The post laser ETDRS grading in the LE showed regression of hemorrhages and neovascularisation constituting MNPDR in 18(36%), SNPDR in 21(42%), VSNPDR in 7(14%) and PDR in 4(8%). There was paucity of studies available in the literature mentioning the pre and post laser ETDRS grading in both right and left eyes. The mean ETDRS score in the RE pre laser, post laser 1 st week and post laser 6 months were 67.60, 60.20 and 67.10 respectively. The P value between pre laser and post laser 1 st week was 0.00 which was statistically significant. The P value between pre laser and post laser 6 months was 0.32 which was not statistically significant. Thus the patients had initial decrease in BCVA in the 1 st week following laser which becomes stable following 6 months after treatment.
Diabetes mellitus (DM) is a global epidemic with significant morbidity. Diabetic retinopathy (DR) & Diabetic macular edema (DME) are the specific microvascular complication of DM and affects 1 in 3 persons with DM. DR/DME remains a
Two general approaches for laser treatment of RAM were described: (1) direct application of laser to RAM surface  and (2) indirect treatment of surrounding neuroepithelium  (with or without coagulation of feeder and draining vessels ). Although direct treat- ment appears to have a more obvious pathophysiological rationale, this approach may be complicated by disrup- tion of RAM wall in the case of excessive thermal damage . On the one hand, with conventional laser photoco- agulation there is no clear boundaries between the direct and indirect approach because the accuracy of the treat- ment is limited by the human factor (both operator- and patient-associated). On the other hand, the excessive thermal damage may be associated with the risk of sub- sequent rupture of the RAM wall . In our study, the most important factor determining the total laser energy was the number of laser burns applied. Since the higher than for conventional laser hit rate in treatment microa- neurysms was already demonstrated for NAVILAS , we concluded that decreased number of laser burns in RAM treatment reflects the higher accuracy of the navi- gated procedure. Therefore, the navigated approach lim- its the zone of laser application exclusively to the RAM
Imai and Iijima 19,20 reported a dramatic reduction in the amplitude and a delay in the implicit time of rabbit eyes 1 day after PRP with a partial recovery of amplitude 4 weeks after treatment. The present study demonstrated partial recovery of the amplitudes and the latencies 6 weeks after the ﬁ nal treatment. Capoferri et al 5 performed ERGs in 16 patients with PDR prior to PRP, in the interval between laser sessions, within 36 hrs of the ﬁ nal session and 4 months later. The analysis of the results showed a signi ﬁ cant decrease in the peak amplitudes of both a- and b-waves in photopic and dark-adapted conditions that occurred as early as between treatment sessions and remained depressed at 4-month follow-up. The lack of recovery in Capoferri et al ’ s study 5 contrasts with the present ﬁ ndings which demonstrated partial recovery of retinal function 6 weeks after completion of PRP. Considering pathophysiology of the PRP, not only func- tional tissue loss would be occurring, but also the burning RPE and retina is associated with cytokine release and subsequent in ﬂ ammation cascades. Hence, in ﬂ ammation and retinal tissue loss are two main components of treat- ment-related ERG drops. Retinal tissue loss is an irrever- sible process; however, the in ﬂ ammation would be resolved over the time which results in improved ERG parameters 6 weeks (in this study) after completion of PRP. It must be noted that glycemic control may affect the ERG parameters; in this study, glycemic status variable was controlled indirectly, by consideration of the stage of diabetic retinopathy through DRSS. One possible explana- tion for lack of recovery in Capoferri et al ’ s study 5 may be uncontrolled glycemic status and/or post-laser in ﬂ amma- tion which might affect ERG changes after the completion of PRP.
The parameters under study were compared by applying Z test i.e., test based on normal distribution, since the sample size was large (n>30). The results were obtained using SPPS 11 version package. The data collected were analysed on the basis of descriptive statistics, mean and standard deviation. The graphs and diagrams were also used to represent the data. Microsoft word and excel had been used to generate graphs and tables.
PRP was performed using Pattern Scan Laser (PASCAL) photocoagulator (OptiMedia, Santa Clara, California, USA) and Volk QuadrAspheric fundus contact lens (Volk Optical Inc. Mentor, OH, USA). The duration was 20 ms for each spot with a spot size of 200 micrometers and spa- cing of 0.75 using a 2 × 2 or 3 × 3 grid pattern. The power range was 200 to 1000 milliWatt, adjusted as needed until retinal whitening was seen for each burn.
In our study, during the 24-h period following the ROP examination, 93.3% (56/60) of infants did not have a sig- nificant systemic or ocular complication. Three times repetition of instillation of phenylephrine 2.5% and tro- picamide 0.5% combination can be considered effective and safe for ROP examinations of premature infants hospitalized in the intensive care unit. Infants with add- itional diseases, such as RDS, should be monitored more carefully after the ROP examination. Efforts should be made to ensure adequate mydriasis to prevent stress resulting from time consuming examinations. The use of tropicamide in place of cyclopentolate may be consid- ered in mydriatic regimens because the duration of ac- tion of tropicamide begins earlier and ends sooner than cyclopentolate. Nurses should be instructed to wipe off the excessive drops which spill out of the eye after instil- ling as the absorption from the eyelid skin can lead to periocular blanching and systemic complications .