Incidence Of Cataract Formation Research Articles

18F-FDG PET/CT Did Not Increase the Risk of Cataract Occurrence in Oncology Patients: A Nationwide Population-Based Cohort Study.

This study aimed to evaluate the risk of cataract formation associated with radiation exposure from 18F-FDG PET/CT in oncology patients, using data from Taiwan’s National Health Insurance Research Database. The exposed group (Group E) consisted of oncology patients receiving 18F-FDG PET/CT within the first year of a cancer diagnosis. The comparison group (Group C) included subjects who had never been exposed to 18F-FDG PET/CT radiation and were propensity score-matched by date of enrolment, age, sex, cancer type, associated comorbidities, and CT utilization. Multiple Cox proportional hazard regression analysis was used to estimate the hazard ratio (HR) of cataract risk due to radiation exposure, while adjusting for potential confounding factors. A total of 703 patients and 1406 matched subjects were in Groups E and C, respectively. The incidence of cataract formation was not significantly higher among subjects in Group E (adjusted HR = 1.264; 95% confidence interval [CI] = 0.845–1.891). Our results revealed that 18F-FDG PET/CT was not a significant risk factor for developing cataracts in oncology patients.

Scleral buckling versus vitrectomy for young japanese patients with rhegmatogenous retinal detachment in the era of microincision surgery: real-world evidence from a multicentre study in Japan.

To evaluate real-world evidence for young Japanese patients with rhegmatogenous retinal detachment (RRD) by retrospectively examining surgical procedures and clinical outcomes in the Japan Clinical Retina Study group. This was a multicentre retrospective study of the medical records of 562 young patients (384 males and 178 females; mean age: 33.0±11.8years) who had been diagnosed with RRD and who underwent surgical procedures in participating centres during the period between April 2013 and August 2016. The selected surgeries were scleral buckling (SB) for 295 eyes (49.7%) and pars plana vitrectomy (PPV) for 262 eyes (44.1%). Between the two surgical procedures, there was no significant difference in the primary anatomical reattachment rate (PARR, SB=92.2%, PPV=93.9%); improvements in vision were noted in both groups. The incidences of proliferative vitreoretinopathy and cataract formation within 1year of PPV were 2.3% (p=0.0047) and 6.5% (p=0.0005), whereas they were 0% and 1.0% in the SB group, respectively. Scleral buckling (SB) and PPV were chosen with almost equal frequency for young patients with RRD. Clinical outcomes for SB and PPV exhibited a similar PARR. The incidence of cataract formation after PPV may constitute an important limitation of the procedure.

Risk Factors for Cataract Formation after Implantable Collamer Lens Implantation: Over a Mean 7.5-Year Follow-Up Period

Purpose: To determine the risk factors and incidence of cataract formation over a long-term mean follow-up of 7.5 years after type V4 implantable collamer lens (ICL) implantation. Methods: We analyzed the preoperative, 3-month postoperative, 3-year postoperative, and last follow-up data of 228 eyes (118 patients) with mean preoperative spherical equivalent of -12.7 D and minimum postoperative follow-up of 3 years. Additionally, we determined the risk factors for cataract formation and calculated the 10.3 year cumulative cataract formation rate and 10.3 year cumulative cataract surgery rate using a survival curve. Results: After type V4 ICL implantation with minimum follow-up of 3 years, the calculated 10.3 year cumulative cataract formation rate was 20% and actual cataracts developed in 34 eyes (14.9%). The 10.3 year cumulative cataract surgery rate was 12% based on a survival curve and actual cataract surgery was performed in 12 eyes (5.3%). The risk factors for cataract formation were age (odds ratio [OR] = 1.10, p = 0.00), preoperative spherical equivalent (OR = 0.90, p = 0.00), crystalline lens thickness (OR = 9.54, p = 0.00), axial length (OR = 1.33, p = 0.00), 3 months postoperative vault (OR = 0.50, p = 0.03), and existence of peripheral touch between ICL optic margin and crystalline lens at last follow-up (OR = 7.84, p = 0.00). Conclusions: We suggest one of the main risk factors for cataract formation after ICL implantation is decreased central vault and peripheral touch between ICL optic margin and crystalline lens. J Korean Ophthalmol Soc 2015;56(6):835-846

Large-Diameter Penetrating Keratoplasty: Indications and Outcomes

To report the indications and outcomes of patients who underwent large-diameter penetrating keratoplasty (LDPK) for the management of peripheral corneal disease. A retrospective chart review and data analysis of patients who underwent LDPK was performed. A retrospective chart review of 35 eyes of 32 patients undergoing LDPK between May 2000 and December 2006 at the Cincinnati Eye Institute/University of Cincinnati was completed. Corneal grafts 8.75 mm or larger were designated as large grafts. Graft diameter ranged from 8.75 mm to 10.0 mm. Indications for cornea transplantation included keratoconus (19), pellucid marginal degeneration (two), keratoconus and pellucid marginal degeneration (five), Fuchs endothelial dystrophy (one), corneal stromal scar (one), postradial keratotomy irregular astigmatism (two), and repeat penetrating keratoplasty (five). No evidence of preoperative stromal neovascularization was seen in any eye. Five of 35 eyes had experienced one previous graft failure. Minimum follow up was 12 months (range, 12-91 months) with a mean follow up of 29.8 months. Preoperative best-corrected visual acuity was 20/100 (range, 20/25 to hand movements), and postoperative best-corrected visual acuity was 20/32 (range, 20/20-20/125). Postoperatively, 43% of patients had 20/40 or better uncorrected visual acuity. Average postoperative manifest cylinder was +2.19 D (range, none to +4.75 D) with 77% of patients having less than +3.00 D of cylinder. The postoperative immunosuppression regimen included topical corticosteroid and topical cyclosporine 0.05%. The incidence of cataract formation in our study was 14.2%. The incidence of secondary glaucoma was 8.8%. Cornea graft rejection was noted in six of 35 eyes with resolution in 4/6. Repeat cornea transplant was required in one of six eyes for severe infectious keratitis, and one of six eyes was lost to follow up. At last follow up, 33 of 35 original grafts were clear with one graft lost to follow up and one eye requiring repeat keratoplasty. No graft rejection was experienced by any patient with a history of prior graft failure. LDPK may result in less postoperative astigmatism without an increased risk of graft failure if managed correctly postoperatively. Topical cyclosporine 0.05% may be a useful adjunct to decrease the incidence of graft rejection and failure. Ophthalmologists performing penetrating keratoplasty should consider a LDPK to reduce postoperative astigmatism and improve visual acuity outcomes in their patients.

Can an Intraoperative Bevacizumab Injection Prevent Recurrent Postvitrectomy Diabetic Vitreous Hemorrhage?

To evaluate the recurrence of vitreous hemorrhage (VH) in patients treated with intravitreal bevacizumab (IVB) injection (2.5 mg/0.1 mL) intraoperatively at the end of vitrectomy for treatment of diabetic nonclearing VH. A prospective pilot study of 30 eyes of 28 consecutive diabetic patients who underwent pars plana vitrectomy and IVB injection intraoperatively at the end of vitrectomy was performed. The amount of VH was graded with slit lamp biomicroscopy by three masked retinal specialists from grade 0 to grade 3. Main outcome measures were rate of recurrence of the VH, improvement in visual acuity, incidence of cataract formation, and postoperative complications through a follow-up of 6 months. The percentage of severe recurrent VH with no fundus details (grade 3) was 7%, 13%, 27%, and 30%, respectively, at 7 days and 1-, 3-, and 6-month follow-up. At 6-month followup, the best-corrected visual acuity improved from 1.00 to 0.4 logMAR (p=0.01) in 21 out of 30 eyes (70%). Nine out 20 (40%) phakic patients developed cataract during the follow-up period, and 7 (31%) of them underwent cataract surgery. The study suggests that intravitreal bevacizumab injection cannot prevent rebleeding in eyes undergoing pars plana vitrectomy for treatment of diabetic vitreous hemorrhage.

Estrogen Protects against Radiation-Induced Cataractogenesis

Cataractogenesis is a complication of radiotherapy when the eye is included in the treatment field. Low doses of densely ionizing space radiation may also result in an increased risk of cataracts in astronauts. We previously reported that estrogen (17-beta-estradiol), when administered to ovariectomized rats commencing 1 week before gamma irradiation of the eye and continuously thereafter, results in a significant increase in the rate and incidence of cataract formation and a decreased latent period compared to an ovariectomized control group. We therefore concluded that estrogen accelerates progression of radiation-induced opacification. We now show that estrogen, if administered continuously, but commencing after irradiation, protects against radiation cataractogenesis. Both the rate of progression and incidence of cataracts were greatly reduced in ovariectomized rats that received estrogen treatment after irradiation compared to ovariectomized rats. As in our previous study, estradiol administered 1 week prior to irradiation at the time of ovariectomy and throughout the period of observation produced an enhanced rate of cataract progression. Estrogen administered for only 1 week prior to irradiation had no effect on the rate of progression but resulted in a slight reduction in the incidence. We conclude that estrogen may enhance or protect against radiation cataractogenesis, depending on when it is administered relative to the time of irradiation, and may differentially modulate the initiation and progression phases of cataractogenesis. These data have important implications for astronauts and radiotherapy patients.

Can a preoperative bevacizumab injection prevent recurrent postvitrectomy diabetic vitreous haemorrhage?

To evaluate the recurrence rate of vitreous haemorrhage (VH) in patients treated with one intravitreal bevacizumab (IVB) injection (2.5 mg/0.1 ml) before planned pars plana vitrectomy for treatment of diabetic non-clearing VH. Prospective pilot study of 32 eyes of 31 consecutive diabetic patients who underwent IVB injection within 1 week before surgery for persistent VH in the presence of active proliferative diabetic retinopathy. Three masked retinal specialists graded the amount of VH from grade 0 to grade 3 with slit-lamp biomicroscopy. Main outcome measures were the rate of recurrence of the VH, improvement in visual acuity, incidence of cataract formation, and postoperative complications through a follow-up of 6 months. The percentage of severe recurrent VH with no fundus details (grade 3) was 3% at 1 week follow-up and 3, 6, and 6% respectively at 1-, 3-, and 6-month follow-up. The mean best-corrected visual acuity (BCVA) improved from 1.6 (1/60) to 0.40 (6/15) logMAR (P=0.02) in 29 out of 32 eyes (91%). In all, 12 out of 22 (54%) phakic eyes developed cataract during the follow-up period, and 10 (31%) of them underwent cataract surgery. Our study suggests that IVB injection few days before planned surgery seems to be efficacious and safe as an adjuvant treatment to prevent rebleeding in eyes undergoing pars plana vitrectomy for treatment of diabetic vitreous haemorrhage. IVB facilitates the surgery and reduces the need for extensive delamination and segmentation, decreasing the possibility of significant early active postoperative VH.

INTRAVITREAL TRIAMCINOLONE ACETONIDE INJECTION AT THE END OF VITRECTOMY FOR DIABETIC VITREOUS HEMORRHAGE

To evaluate the clinical outcome and complications of intravitreal injections of triamcinolone acetonide in patients undergoing pars plana vitrectomy for treatment of diabetic nonclearing vitreous hemorrhage. This prospective, randomized clinical trial study included 72 consecutive patients (72 eyes) who underwent pars plana vitrectomy for treatment of diabetic nonclearing vitreous hemorrhage. 38 patients received an intravitreal injection of 4 mg (0.1 cc) of triamcinolone acetonide at the end of surgery. Main outcome measures were rate of recurrent early vitreous hemorrhage, reoperation, intraocular pressure, visual acuity, and incidence of cataract formation. Mean follow-up time was 6 months. Rate of early rebleeding and reoperation were lower in patients taking intravitreal triamcinolone (P = 0.003 and 0.03, respectively). Visual acuity 6 months after operation was better in study group (P < 0.001). Mean intraocular pressure was higher 1 day and 1 week after procedure in study group compared with control group (P < 0.001 and 0.002, respectively); however, in other times its differences were not significant. No significant difference in rate of nuclear sclerosis and cortical cataract formation and other complication was noted between the two groups. However, there was a significantly increased rate of posterior subcapsular progression in a dose dependent manner in the study group versus control (P = 0.011). The present clinical study suggests that intravitreal injection of triamcinolone acetonide is effective in the prevention of rebleeding in eyes undergoing pars plana vitrectomy for treatment of diabetic vitreous hemorrhage.

Metaanalysis of cataract development after phakic intraocular lens surgery

We performed a systematic literature review to determine the incidence of and predisposing factors for cataract after phakic intraocular lens (pIOL) implantation. Of the 6338 eyes reported, 4.35% were noted to have new-onset or preexisting progressive cataract. The incidence of cataract formation was 1.29%, 1.11%, and 9.60% with anterior chamber, iris-fixated, and posterior chamber (PC) pIOLs, respectively. In the PC pIOL group, early cataract formation was related to surgical trauma and late-onset cataract was related to IOL-crystalline lens contact. Analysis of cataract progression in eyes with preexisting cataract showed a progression rate of 29.5% after pIOL surgery. These results suggest that cataract formation is most likely to occur after PC pIOL implantation. Patients with preexisting progressive cataract should be informed about the possibility of cataract progression and possible need for cataract surgery after pIOL implantation. Cataract surgical intervention resulted in restoration of visual acuity.

25-gauge, sutureless vitrectomy and standard 20-gauge pars plana vitrectomy in idiopathic epiretinal membrane surgery: a comparative pilot study

The aim of the study was to evaluate the safety and functional outcome of a small incision, sutureless vitrectomy in the treatment of idiopathic epiretinal membranes (ERM) compared with a standard 20-gauge vitrectomy system. Forty-six consecutive patients with idiopathic ERM were recruited for this study and prospectively evaluated. In group 1 (n=26) we used a transconjunctival sutureless 25-gauge vitrectomy system (TSV), patients in group 2 (n=20) were operated on using a standard 20-gauge vitrectomy system. The ERM was removed and the internal limiting membrane (ILM) was peeled in all eyes. Surgery-related complications, operating time, intraoperative balanced salt solution (BSS) consumption, postoperative discomfort, postoperative intraocular inflammation, lens opacification, and long-term visual outcome are reported and compared. No surgery-related complications were observed in either group. Operating time was shorter in group 1 compared with group 2 (mean 15.6 and 29.6 min respectively). Intraoperative amount of BSS consumption was less in group 1 (mean 28 ml in group 1 and 42 ml in group 2). Postoperative discomfort and intraocular inflammation were significantly reduced in the 25-gauge group. In the 20-gauge group cataract formation requiring surgery was observed in two eyes. Visual acuity improved significantly in both groups. The 25-gauge group improved on average by more lines of vision and the improvement in vision was more rapid. The TSV system is a safe and efficient surgical technique for ERM surgery. Operating time is significantly reduced, minimizing surgery-induced trauma, and reducing postoperative intraocular inflammation and the patients' discomfort. The incidence of cataract formation may be less using TSV. Postoperative recovery is accelerated.

Effect of Estrogen on Radiation-Induced Cataractogenesis

Cataractogenesis is a widely reported late effect that is observed in patients receiving total-body irradiation (TBI) prior to bone marrow transplantation or radiotherapy for ocular or head and neck cancers. Recent studies indicate that estrogens may protect against age-related and drug-induced cataracts. Moreover, other reports suggest that estrogen possesses antioxidant properties. Since the effect of estrogen on radiation cataractogenesis is unknown, we wished to determine whether estrogen modulates radiation-induced opacification of the lens. Intact or ovariectomized Sprague-Dawley rats were treated with either 17-beta-estradiol or an empty silastic capsule. The right orbit was then irradiated with either 10 or 15 Gy of (60)Co gamma rays using a Leksell Gamma Knife, and lenses were examined at various times postirradiation with a slit lamp or evaluated for light transmission. We found that for ovariectomized rats irradiated with 15 Gy, the lens opacity and the incidence of cataract formation in the estradiol-treated group were significantly increased compared to the control group at the end of the 25-week period of observation. Cataract incidence was also high in irradiated eyes of ovary-intact animals at 25 weeks postirradiation but was greatly reduced in the ovariectomized control group, with less than half of irradiated eyes showing evidence of cataractogenesis. Thus, after irradiation with 15 Gy of gamma rays, estrogen increased the incidence of cataract formation. We also observed that although the incidence of cataract formation in rats irradiated with 10 Gy and receiving continuous estrogen treatment was not altered compared to rats in the control group that did not receive estrogen, the latent period for posterior subcapsular cataract formation decreased and the severity of the anterior cataract increased. Taken together, our data suggest that estrogen accelerates progression of radiation-induced opacification.

Dose-effect relationship for cataract induction after single-dose total body irradiation and bone marrow transplantation for acute leukemia

Purpose : To determine a dose-effect relationship for cataract induction, the tissue-specific parameter, α/β, and the rate of repair of sublethal damage, μ value, in the linear-quadratic formula have to be known. To obtain these parameters for the human eye lens, a large series of patients treated with different doses and dose rates is required. The data of patients with acute leukemia treated with single-dose total body irradiation (STBI) and bone marrow transplantation (BMT) collected by the European Group for Blood and Marrow Transplantation were analyzed. Methods and Materials : The data of 495 patients who underwent BMT for acute leukemia, who had STBI as part of their conditioning regimen, were analyzed using the linear-quadratic concept. The end point was the incidence of cataract formation after BMT. Of the analyzed patients, 175 were registered as having cataracts. Biologic effective doses (BEDs) for different sets of values for α/β and μ were calculated for each patient. With Cox regression analysis, using the overall chi-square test as the parameter evaluating the goodness of fit, α/β and μ values were found. Risk factors for cataract induction were the BED of the applied TBI regimen, allogeneic BMT, steroid therapy for >14 weeks, and heparin administration. To avoid the influence of steroid therapy and heparin on cataract induction, patients who received steroid or heparin treatment were excluded, leaving only the BED as a risk factor. Next, the most likely set of α/β and μ values was obtained. With this set, the cataract-free survival rates were calculated for specific BED intervals, according to the Kaplan-Meier method. From these calculations, cataract incidences were obtained as function of the BED at 120 months after STBI. Results : The use of BED instead of the TBI dose enabled the incidence of cataract formation to be predicted in a reasonably consistent way. With Cox regression analysis for all STBI data, a maximal chi-square value was obtained for α/β = 1.75 Gy and μ = 0.75 h −1. When Cox regression analysis was applied for patients who had no steroid treatment after BMT, a maximal chi-square value was obtained for α/β = 1 Gy and μ = 0.6 h −1. Cox regression analysis was repeated using the data of patients who had not received posttransplant steroid treatment and also no heparin administration; we found α/β = 0.75 Gy and μ = 0.65 h −1. An increased cataract incidence was observed after steroid treatment of >14 weeks and heparin administration. Conclusion : The α/β value of 0.75 Gy and a μ value of 0.65 h −1 found for the eye lens are characteristic for late-responding tissues. The incidence of cataract formation can now be quantified, taking into account the values calculated for α/β and μ, TBI dose, and dose rate. Also, the reduction in cataract incidence as a result of lens dose reduction by eye shielding can be estimated.

The use of explant lens culture to assess cataractogenic potential.

Explanted cultures of crystalline lenses have been used to investigate mechanisms of xenobiotic-induced cataract formation. However, very few studies have utilized mechanistic information to predict the cataractogenic potential of structurally diverse xenobiotics. The present investigation outlines how visual assessment of lens clarity, biochemical endpoints of toxicity, and mechanisms of lenticular opacity formation can be used to select compounds with a lower probability of causing cataract formation in vivo. The rat lens explant culture system has been used to screen thiazolidinediones against ciglitazone for their direct cataractogenic potential in vitro. The two compounds that were selected as development candidates (englitazone and darglitazone) did not produce cataracts in rats exposed daily for 3 months. The culture system has also been used to illustrate that the lens is capable of metabolizing compounds to reactive intermediates. In this example, the toxicity of S-(1,2-dichlorovinyl)-L-cysteine (DCVC), a model cataractogen, was attenuated by inhibiting lenticular cysteine conjugate beta-lyase metabolism using aminooxyacetic acid. Finally, this model was used retrospectively to investigate the cataractogenic potential of CJ-12,918 and CJ-13,454 in rats. These compounds showed differences in the incidence of cataract formation in vivo based on differences in hepatic metabolism and penetration of parent drug and metabolites into the lens. The rank order of cataractogenic potential in vitro correlated better with in vivo results when an induced S9 microsomal fraction was added to the culture media. However, the model did not correctly predict the cataractogenic potential of ZD2138, a structurally similar compound. These studies illustrate the use of explant culture to assess mechanisms of cataract formation and outline its use and limitations for predicting cataractogenic potential in vivo.

Acquired cataracts after argon laser photocoagulation for retinopathy of prematurity

Purpose : Our purpose was to determine the incidence of cataract after argon laser photocoagulation of the retina in infants with retinopathy of prematurity (ROP). Methods : We reviewed medical records of 189 consecutive infants undergoing argon laser photocoagulation for acute ROP between 1993 and 1996. Birth weight, estimated gestational age at birth, chronologic and postconceptional ages at the time of treatment, ROP outcome, and the postoperative occurrence of cataract were recorded. Results : A total of 374 eyes in 189 infants were treated for threshold ROP. Mean birth weight was 916 gm (range 480 to 2500 gm), mean postconception age at birth was 26.4 weeks (range 23.5 to 34 weeks), and mean postconception age at surgery was 36.2 weeks (range 33 to 47 weeks). A favorable anatomic outcome occurred in 90% of eyes. However, severe macular traction, macular fold, or retinal detachment developed in 10% of eyes. A total of four eyes (1%) had cataracts. Laser-induced cataracts were diagnosed in only two eyes. A third eye had a posterior subcapsular cataract that may or may not have resulted from the laser treatment. In a fourth patient a unilateral punctate opacity judged to be visually insignificant was noted at surgery but it was not progressive. All patients who had cataracts had a persistent tunica vasculosa lentis; however, there was no statistically significant difference in the incidence of cataract formation in eyes with persistent tunica vasculosa lentis compared with eyes without it ( p = 0.057). Conclusion : Argon laser photocoagulation remains an effective alternative to transscleral cryotherapy in the treatment of threshold ROP. The incidence of cataract formation is approximately 1% and may be more likely to occur when persistent hyaloidal vessels are present on the lens.

Incidence of cataracts in rhesus monkeys treated with whole-body irradiation.

The incidence of cataract formation was investigated in rhesus monkeys exposed to different doses of whole-body irradiation. Application of 850-900 rad (8.5-9 Gy) caused cataracts in 17% of the monkeys within 3 years after treatment; after 10 to 15 years, incidence increased to 100%. "Young" lenses showed a significantly lower incidence than "adult" lenses, although no differences in the stage of cataractogenesis could be demonstrated. Sex differences did not play a role in incidence and severity of cataracts. Lower doses (400 rad or 4 Gy) did not cause cataracts. In view of the close similarity between monkeys and humans, these results indicate that a single dose of 850-900 rad, sometimes employed in the treatment of acute myeloid leukemia in children, carries a strong risk of cataract development.

Lens Opacification in Mice Exposed to 14-MeV Neutrons

The induction of lens opacification in mice exposed to 14-MeV neutrons was evaluated by counting the number of opacities observed in the posterior region of the lens using a slit-lamp microscope. The incidence of cataract formation in the anterior region of the lens was also observed. Serial observations were carried out from 3 up to 25 months after irradiation. Male hybrid mice (C54B1 X C3H), 75 days old at the time of the exposure, have been used. A linear progression of opacities was observed with age at a rate depending on the dose. By comparison with 250-kVp X rays the RBE was found to increase, with decreasing dose, from 9 to 21. The incidence of opacification in the anterior region of the lens gives an RBE value of 8. Split-dose irradiations were carried out with an interval of 24 hr between doses. There was very little difference in the number of opacities observed after single or fractionated neutron doses of approximately the same total amount. In contrast, fractionation of the X-ray dose reduced the effectiveness of the irradiation.