Impact of Age on Scleral Buckling Surgery for Rhegmatogenous Retinal Detachment

PURPOSE: The purpose of this study is to investigate new prognostic factors in associated with primary anatomical failure after scleral buckling (SB) for uncomplicated rhegmatogenous retinal detachment (RRD). METHODS: The medical records of patients with uncomplicated RRD treated with SB were retrospectively reviewed. Eyes with known prognostic factors for RRD, such as fovea-on, proliferative vitreoretinopathy, pseudophakia, aphakia, multiple breaks, or media opacity, were excluded. Analysis was performed to find correlations between anatomical success and various parameters, including age. RESULTS: This study analyzed 127 eyes. Binary logistic regression analysis revealed that older age (≥35) was the sole independent prognostic factor (odds ratio, 3.5; p = 0.022). Older age was correlated with worse preoperative visual acuity (p < 0.001), shorter symptom duration (p < 0.001), presence of a large tear (p < 0.001), subretinal fluid drainage (p < 0.001), postoperative macular complications (p = 0.048), and greater visual improvement (p = 0.003). CONCLUSIONS: Older age (≥35) was an independent prognostic factor for primary anatomical failure in SB for uncomplicated RRD. The distinguished features of RRD between older and younger patients suggest that vitreous liquefaction and posterior vitreous detachment are important features associated with variation in surgical outcomes.

Prognostic Factors of Anatomical Success in Scleral Buckling for High Myopic Rhegmatogenous Retinal Detachment

PURPOSE: To assess the prognostic factors associated with anatomical success of scleral buckle (SB) for rhegmatogenous retinal detachment (RRD) in high myopia patients. METHODS: The medical records of RRD in highly myopic eyes treated with SB from January 2009 to December 2013 were reviewed retrospectively. Cases with history of intraocular surgery including phacoemulsification and vitrectomy were excluded. Correlations between anatomical success and the parameters of age, sex, preoperative visual acuity, axial length, presence of large tear, presence of horseshoe tear, the number of tears, involved fovea, and extent of detachment were analyzed. RESULTS: This study included 80 eyes of 80 patients. Average age and axial length were 32.3 ± 13.4 and 26.753 ± 0.961 mm, respectively. Sixty-nine eyes (86.3%) were reattached following primary surgery. Univariate analysis revealed that age (p = 0.011), presence of large tear (p = 0.002), and presence of horseshoe tear (p = 0.044) were correlated with anatomical success after SB. Based on multivariate logistic regression analysis, age was the sole independent prognostic factor (odds ratio = 1.086, 95% confidence interval = 1.022~1.154, p = 0.004). CONCLUSIONS: A younger age is associated with a higher rate of primary anatomical success of SB for RRD in highly myopic eyes. In young, highly myopic patients with RRD, SB should be considered as the primary procedure.

The Effectiveness of Pediatric Blood Culture Bottle in Endophthalmitis

PURPOSE: To investigate the effectiveness of the pediatric blood culture bottle for vitreous sample culture in endophthalmitis patients. METHODS: All consecutive cases with clinically suspected endophthalmitis treated and cultured in our institution between January 2009 and June 2013 were included in the study. Vitreous samples were obtained by vitreous needle aspiration (tap), anterior chamber aspiration, or mechanized vitreous biopsy (vitrectomy). The samples obtained using the conventional method until August 2011 were classified as group I. Since August 2011, the BacT/Alert PF pediatric blood culture bottle (bioMerieux, Marcy l'Etoile, France) was used for culture in group II. We investigated age, gender, biopsy method, cause of infection, use of antibiotics, bacterial culture, and culture positive rate. RESULTS: Thirty-three cases were included in group I and 17 cases in group II. There was no significant difference in age, gender, sampling technique, cause of infection, and use of antibiotics between the 2 groups. The culture positive rate in group II (60.7%) was significantly higher than group I (33.3%, p = 0.032). In group II, Enterococcus feacalis was the most common pathogen (8 eyes). In group I, Streptococcus pneumoniae and Pseudomonas aeruginosa were confirmed in 3 cases. CONCLUSIONS: The pediatric blood culture bottle can be used successfully in the examination of clinically suspected endophthalmitis. The method showed higher culture positive rate compared with the conventional method. This technique is simple and maintaining a supply of fresh agar media is not necessary.

Myopic Shift and Cataract Change after Lens Sparing Vitrectomy in Patients with Idiopathic Epiretinal Membrane in Their 5th and 6th Decade

PURPOSE: To determine the myopic shift and cataract change after lens sparing vitrectomy (LSV) in patients with idiopathic epiretinal membrane (ERM) in their 5th and 6th decade of life. METHODS: The medical records of patients undergoing LSV for idiopathic ERM from 2008 to 2012 were reviewed. Patients with previous intraocular surgery, preoperative significant cataract, under 40 or over 60 years of age and a follow-up period of less than 6 months were excluded. The change in refractive errors, visual acuity, and cataract grade were evaluated for 6 months after LSV as well as the correlation between myopic shift and cataract change at 6 months after LSV. RESULTS: Twenty-eight eyes were included in this study. The cataract status worsened by 1.07 levels, myopia progressed by 3.13 diopters (p < 0.001), and uncorrected visual acuity (log MAR) decreased from 0.73 to 0.98 (p = 0.022) at 6 months after LSV. Additional cataract surgery was performed in 22 eyes (78.6%) at 13.6 months on average during the follow-up period (average 16.9 months). In 6 eyes (21.4%) having myopic change below 1.0 diopters, crystalline lens was preserved for 36 months after vitrectomy. Conversely, 22 eyes (78.6%) with myopic change over 1.5 diopters required cataract surgery. Therefore, myopic change over 1.5 diopters could be a major postoperative change predicting the necessity for cataract surgery (p < 0.001). CONCLUSIONS: LSV for ERM caused a significant myopic shift and cataract changes in patients in their 5th and 6th decade of life and additional cataract surgery was required in 78.6% of patients within 3 years after vitrectomy. The myopic shift over 1.5 diopters at 6 months after vitrectomy could be a major postoperative change predicting the necessity for cataract surgery.

Internal Limiting Membrane Peeling Using 0.025% Brilliant Blue G During Vitrectomy

PURPOSE: To evaluate 0.025% brilliant blue G (BBG) for staining the internal limiting membrane (ILM) during vitrectomy. METHODS: In a retrospective, non-comparative clinical case series, we analyzed consecutive 111 patients who underwent pars plana vitrectomy and removal of the ILM after staining using BBG solution. BBG was dissolved and diluted with balanced salt solution at a concentration of 0.025% and then sterilized by filtering through a 0.22 microm millipore filter. The prepared BBG solution was injected into the vitreous cavity over the macula after removal of the vitreous and excessive solution was removed immediately. RESULTS: The ILM was successfully removed without use of additional adjuvant in all cases. Mean best corrected visual acuity (log MAR) was significantly improved from 0.80 +/- 0.44 at baseline to 0.40 +/- 0.39 at 6 months postoperatively (p < 0.001). One case each of endophthalmitis and diabetic papillopathy developed. The relationship when using BBG solution was not identified as complications were not observed in the other patients who underwent vitrectomy using the same BBG solution on the same day. One idiopathic epiretinal membrane patient had visual acuity loss more than 2 lines. During the follow-up period, other complications suspected to be associated with the use of BBG solution were not observed. CONCLUSIONS: A BBG solution (0.025%) was effective in staining the ILM for removal. Complications associated with the use of BBG solution were not observed.

Myopic Shift and Cataract Change after Lens Sparing Vitrectomy in Patients with Idiopathic Epiretinal Membrane in Their 5th and 6th Decade

PURPOSE: To determine the myopic shift and cataract change after lens sparing vitrectomy (LSV) in patients with idiopathic epiretinal membrane (ERM) in their 5th and 6th decade of life. METHODS: The medical records of patients undergoing LSV for idiopathic ERM from 2008 to 2012 were reviewed. Patients with previous intraocular surgery, preoperative significant cataract, under 40 or over 60 years of age and a follow-up period of less than 6 months were excluded. The change in refractive errors, visual acuity, and cataract grade were evaluated for 6 months after LSV as well as the correlation between myopic shift and cataract change at 6 months after LSV. RESULTS: Twenty-eight eyes were included in this study. The cataract status worsened by 1.07 levels, myopia progressed by 3.13 diopters (p < 0.001), and uncorrected visual acuity (log MAR) decreased from 0.73 to 0.98 (p = 0.022) at 6 months after LSV. Additional cataract surgery was performed in 22 eyes (78.6%) at 13.6 months on average during the follow-up period (average 16.9 months). In 6 eyes (21.4%) having myopic change below 1.0 diopters, crystalline lens was preserved for 36 months after vitrectomy. Conversely, 22 eyes (78.6%) with myopic change over 1.5 diopters required cataract surgery. Therefore, myopic change over 1.5 diopters could be a major postoperative change predicting the necessity for cataract surgery (p < 0.001). CONCLUSIONS: LSV for ERM caused a significant myopic shift and cataract changes in patients in their 5th and 6th decade of life and additional cataract surgery was required in 78.6% of patients within 3 years after vitrectomy. The myopic shift over 1.5 diopters at 6 months after vitrectomy could be a major postoperative change predicting the necessity for cataract surgery.

Internal Limiting Membrane Peeling Using 0.025% Brilliant Blue G During Vitrectomy

PURPOSE: To evaluate 0.025% brilliant blue G (BBG) for staining the internal limiting membrane (ILM) during vitrectomy. METHODS: In a retrospective, non-comparative clinical case series, we analyzed consecutive 111 patients who underwent pars plana vitrectomy and removal of the ILM after staining using BBG solution. BBG was dissolved and diluted with balanced salt solution at a concentration of 0.025% and then sterilized by filtering through a 0.22 microm millipore filter. The prepared BBG solution was injected into the vitreous cavity over the macula after removal of the vitreous and excessive solution was removed immediately. RESULTS: The ILM was successfully removed without use of additional adjuvant in all cases. Mean best corrected visual acuity (log MAR) was significantly improved from 0.80 +/- 0.44 at baseline to 0.40 +/- 0.39 at 6 months postoperatively (p < 0.001). One case each of endophthalmitis and diabetic papillopathy developed. The relationship when using BBG solution was not identified as complications were not observed in the other patients who underwent vitrectomy using the same BBG solution on the same day. One idiopathic epiretinal membrane patient had visual acuity loss more than 2 lines. During the follow-up period, other complications suspected to be associated with the use of BBG solution were not observed. CONCLUSIONS: A BBG solution (0.025%) was effective in staining the ILM for removal. Complications associated with the use of BBG solution were not observed.

Early Capsular Block Syndrome after Phacoemulsification with Posterior Chamber IOL Insertion Combined with Vitrectomy

PURPOSE: To report early capsular block syndrome (CBS) after phacoemulsification with posterior chamber intraocular lens (IOL) insertion combined with vitrectomy. METHODS: Medical records of 622 eyes of 589 patients who had combined phacoemulsification, IOL implantation and vitrectomy between March 2009 and December 2011 were retrospectively reviewed. Among patients with CBS occurring within 1 month of surgery, the patient's baseline characteristics, type of IOL and ophthalmic viscoelastic devices were analyzed. RESULTS: Nine patients (1.45%) developed CBS with typical capsular bag distension. All CBS occurred within 2 weeks after the surgery. Hydrophilic, large optics and no angulation between optic and haptic were related with the occurrence of CBS. Nd:YAG laser capsulotomy (5 eyes), and surgical capsulectomy (2 eyes) resolved CBS successfully. In 2 eyes with gas tamponade, CBS resolved without intervention with the absorption of gas. CONCLUSIONS: CBS may develop after phacoemulsification with PC IOL insertion combined with vitrectomy and/or vitreous tamponade. Hydrophilic material, large optics and no angulation were risk factors of capsular block by enhancing adhesion between the capsulorrhexis and the optic.

Risk Factors of Retinal Detachment after Acute Retinal Necrosis

PURPOSE: Retinal detachment (RD) complicated in acute retinal necrosis (ARN) is difficult to be treated and a main cause of blindness. The factors associated with RD in ARN were investigated. METHODS: Patients with ARN who were diagnosed and treated from Jan, 2008 to Dec, 2012 were reviewed retrospectively. The eyes were classified into the group I without RD, and the group II with RD. Early vitrectomy, history of ARN in the other eye, extent of necrosis, symptom duration and intravitreal injection of anti-viral drug were evaluated. RESULTS: Of 22 eyes of 20 patients, 11 eyes were included in each group. Symptom duration of 8.0 days in the group I was shorter than 15.8 days in the group II (p = 0.005). There were no macular involvement at initial exam in the group I and 5 eyes (45%) in the group II (p = 0.017). Five eyes (45%) in the group I and 0 eye (0%) in the group II had history of ARN in the other eye (p = 0.017). Six eyes (55%) in the group I and 1 eye (9%) in the group II underwent early vitrectomy (p = 0.031). Age, baseline visual acuity, and intravitreal injection of antiviral agent were not related to RD (p = 0.294-0.699). CONCLUSIONS: Broader necrosis and longer symptoms duration were related to occurrence of RD. Correlation of Lower risk of RD with ARN history in the other eye would result from earlier diagnosis and treatment. Early vitrectomy seems to be effective to prevent RD in ARN.

Inflammatory Cytokines in the Vitreous of Rabbits after Photocoagulation Using Pattern Scanning and Conventional Laser

PURPOSE: To compare concentration of cytokines in the vitreous of rabbit eyes after photocoagulation using a short-pulse pattern scanning laser (PASCAL) or a conventional laser. METHODS: Laser photocoagulation was performed using PASCAL (duration 0.02 seconds) in the right eyes and a conventional laser (duration 0.1 seconds) in the left eyes of 13 pigmented rabbits. To obtain ophthalmoscopically similar mild burns, power was adjusted during the photocoagulation. The rabbits were sacrificed at 1, 3 or 7 days after photocoagulation to investigate histological changes. Levels of interleukins (IL)-1beta, IL-6, IL-8 and tumor necrosis factor (TNF)-alpha in the vitreous humors of ten rabbits were measured using enzyme-linked immunosorbent assay before treatment and at 1, 3 and 7 days after photocoagulation. RESULTS: Histological changes were comparable between the two groups. IL-1beta and TNF-alpha were not detectable. IL-6 did not change significantly. IL-8 increased at day 3 and day 7, but no significant difference was observed between the two groups (p>0.05). CONCLUSIONS: When ophthalmoscopically similar mild burn intensity was achieved, conventional and PASCAL treatments of rabbit eyes caused no difference in intravitreal concentration of inflammatory cytokines.

Lens-Save Versus Phacoemulsification with Intraocular Lens Implantation in Primary Vitrectomy for Phakic Rhegmatogenous Retinal Detachment

PURPOSE: To compare lens-save and simultaneous phacoemulsification with intraocular lens implantation in primary vitrectomy for phakic rhegmatogenous retinal detachment (RRD). METHODS: A retrospective comparative analysis of 54 consecutive eyes from 54 phakic RRD patients who underwent vitrectomy with a minimum of 12 months of follow-up was performed. The patients were divided into the vitrectomy group and the combined group (patients who underwent vitrectomy with concurrent cataract surgery). The main outcome measures were the best corrected visual acuity (BCVA), anatomical success rate, complications and cataract status according to LOCSIII grading. RESULTS: Baseline characteristics were similar in both groups, except for age and cataract status. The mean age was 46.9 year in the vitrectomy group (n = 20) and 60.5 years in the combined group (n = 34) (p < 0.001). The postoperative BCVA (log MAR) improved from 1.27 and 1.30 at baseline to 0.45 and 0.28 at 12 months (p < 0.05), respectively, which was not a significant difference between the 2 groups. In the vitrectomy group, cataract status was changed from 1.8 at baseline to 2.5 at 12 months (p = 0.001). Two patients (11.1%) had an additional cataract surgery performed. The primary anatomical success rate was 90.0% in the vitrectomy group and 94.1% in the combined group. CONCLUSIONS: The vitrectomy group and combined group had similar results in the repair of phakic RRD. Although postoperative cataract progression was noted, lens should be saved in vitrectomy for young patients, as significant cataract is uncommon.

Bilateral Acute Myopia and Angle-Closure Due to Ciliochoroidal Effusion in Vogt-Koyanagi-Harada Syndrome

PURPOSE: To report a case of bilateral acute myopia and angle-closure with ciliochoroidal detachment in Vogt-Koyanagi-Harada (VKH) syndrome. CASE SUMMARY: A 43-year-old Korean woman diagnosed with VKH syndrome underwent intravenous methylprednisolone steroid pulse treatment. After oral medication was given for 2 days, the anterior chambers became shallow in both eyes. Intraocular pressure (IOP) increased to 25 mm Hg in the right eye and 23 mm Hg in the left eye. Subretinal fluid increased and visual acuity decreased with myopic shift in both eyes. IOP did not decrease despite maximum tolerated medical therapy. Ultrasound biomicroscopy (UBM) revealed that ciliochoroidal effusion caused forward displacement of the lens-iris diaphragm, which resulted in anterior chamber shallowing and angle closure in both eyes. The patient was treated with cycloplegic eyedrops and intravenous steroid pulse therapy. After intravenous steroid pulse treatment was given for 2 days, the anterior chambers became deep in both eyes. IOP reduced to 13 mm Hg and 14 mm Hg in the right and left eye respectively. Visual acuity increased with normalization of myopic shift. UBM revealed that the ciliochoroidal effusion had resolved in both eyes.

Histopathologic Features of Triamcinolone Deposits in Refractory Steroid-Induced Glaucoma after Subtenon Triamcinolone Injection

PURPOSE: To report the removal of subtenon triamcinolone precipitates in patients with refractory steroid-induced glaucoma following subtenon triamcinolone injection. CASE SUMMARY: A 72-year-old male patient with diabetic retinopathy had cystoid macular edema in the right eye. The patient received a posterior subtenon injection of triamcinolone acetonide and developed intractable glaucoma one month after the injection in the right eye. Corticosteroid-deposit was excised three month after the injection. The intraocular pressure decreased to normal within one month after surgery and remained normal for seven months after surgery. A 42-year-old man with bilateral chronic recurrent anterior uveitis received a posterior subtenon triamcinolone acetonide injection in both eyes. The patient developed refractory steroid-induced glaucoma one month after the injection in the right eye. Corticosteroid-deposit was excised six months after the injection in the right eye. The patient's intraocular pressure decreased to normal within two weeks after surgery and remained normal. Light microscopy showed a fibrous capsule encapsulating an amorphous whitish material. The excised specimen with polarized light showed birefringence of triamcinolone crystals within an encapsulated cyst. CONCLUSIONS: Removal of subtenon triamcinolone acetonide precipitate may facilitate the management of patients developing increased intraocular pressure unresponsive to maximum tolerable medical therapy and should be considered before performing glaucoma filtration surgery.

Clinical Outcomes of the Surgical Management with Dislocated Posterior Chamber Intraocular Lens

PURPOSE: To evaluate the clinical outcomes of the surgical treatment in patients with dislocation of an intraocular lens (IOL). METHODS: The present study investigated the postoperative naked visual acuity, corrected visual acuity, astigmatism, and postoperative complications in patients with a minimum follow-up of 1 month after the surgical treatment of a dislocated posterior chamber IOL. RESULTS: The study included 48 eyes of 48 patients (32 males and 16 females) with an age ranging from 33 to 76 years with a mean of 56.7 years at initial visit. The mean time interval from cataract extraction and IOL implantation to dislocation of IOL was 4.9 years. The IOL was exchanged in 13 eyes and was repositioned in 35 eyes. The IOL was repositioned without tying in 11 eyes, by scleral fixation with tying inside the eye in 10 eyes, and by scleral fixation with tying outside the eyeball in 14 eyes. The mean naked visual acuity improved from 1.21 +/- 0.70 to 0.70 +/- 0.48 (p = 0.001) and the best corrected visual acuity improved significantly from 0.82 +/- 0.68 to 0.35 +/- 0.30 (p = 0.002). Among the repositioned IOLs managed by IOL repositioning using scleral fixation with tying inside the eye, 4 eyes re-dislocated. These eyes were re-treated for a second time with IOL repositioning and scleral fixation with tying outside the eye. CONCLUSIONS: Surgical management of dislocated IOLs resulted in significant improvement of visual acuity. Scleral fixation with tying inside the eye had a high risk of re-dislocation because of the difficulty in tightly securing the knot.

Bell's Phenomenon during Screening Examination for Retinopathy of Prematurity

PURPOSE: Bell's phenomenon (BP), which may disturb screening examinations for retinopathy of prematurity (ROP), is known to present infrequently in premature babies. Stress associated with the examinations can influence expression of BP. The authors of the present study evaluated BP during examinations for ROP. METHODS: The present study included 102 eyes of 51 premature babies. Expression of BP was assessed at 3 steps of the examination in the following order: after insertion of a speculum, after illumination of an indirect ophthalmoscope and after scleral depression. The relationship between the expression of BP and the gestational age at the examination was analyzed in each step of the examination. RESULTS: The frequency of BP after the speculum insertion and the illumination was 77% to 92% in infants 32 weeks of age or younger, and decreased significantly to 16% to 57% in infants 42 weeks of age or older (p < 0.005). BP after the scleral depression had no significant association with the gestational age. Frequency of BP increased significantly as the steps of the examination proceeded (p < 0.01). CONCLUSIONS: BP was frequent in premature infants during ROP examination in spite of neurological immaturity. The examiner should take BP into consideration, which frequently occurs in younger infants.

Retinal Dot Hemorrhage and Internal Limiting Membrane Injury during Epiretinal Membrane Peeling

PURPOSE: To evaluate the relationship between retinal dot hemorrhage that occurred during membrane peeling (MP) and the damage to the internal limiting membrane (ILM) at idiopathic epiretinal membrane (ERM). METHODS: The authors of the present study retrospectively reviewed 50 eyes of 50 consecutive patients who underwent vitrectomy with MP for idiopathic ERM. For all the patients, the ILM was stained with indocyanine green following MP. ILM damage was evaluated using microscopy during the operation. Tissue was examined by light and electron microscopy. Whether or not retinal hemorrhage occurred during the MP and the location of the hemorrhage were also investigated. RESULTS: During the MP for idiopathic ERM, ILM damage was observed in 43 (86%) of 50 eyes, and some defects of the ILM due to simultaneous removal with the ERM were observed in 37 (74%) of 50 eyes. Retinal dot hemorrhage occurred during the MP in 32 eyes (64%) and did not occur in 18 eyes (36%). In 32 eyes with retinal hemorrhage, ILM damage was observed in 30 eyes (94%). Large or small defects of the ILM due to simultaneous removal with the ERM were observed in 27 of 30 eyes, and ILM tear was observed in 3 eyes. The hemorrhage occurred in 2 eyes without gross ILM damage during the MP. Among 18 eyes without retinal hemorrhage, large or small defects of the ILM due to simultaneous removal with the ERM were observed in 10 eyes (56%). ILM tear was observed in 2 eyes, ILM detachment was observed in 1 eye, while ILM remained intact in 5 eyes (28%). The number of eyes where both ERM and ILM were peeled simultaneously was significantly higher in the cases with retinal hemorrhage (p = 0.047). Cases of hemorrhage in Gass grade 2 were statistically higher than that in Gass grade 1 (p = 0.015). OCT type of ERM did not have significant correlation with retinal hemorrhage or ILM damage during the MP. CONCLUSIONS: During the MP for idiopathic ERM, ILM damage was observed in 86% of patients, and some defects of the ILM due to simultaneous removal with ERM were observed in 74% of patients. It is highly suggestive that ILM is damaged at the hemorrhage site if retinal dot hemorrhage occurred during the MP for idiopathic ERM.

Posterior Subtenon Triamcinolone Acetonide Injection for Refractory Diabetic Macular Edema in Vitrectomized Eye

PURPOSE: To evaluate the effect of posterior subtenon injection of triamcinolone acetonide (TA) in patients with refractory diabetic macular edema (DME) after vitrectomy. METHODS: Seventeen vitrectomized eyes in 16 patients with DME underwent a posterior subtenon injection of TA (40 mg/1.0 ml) and were followed-up for more than six months. Visual acuity (VA, logMAR) and central subfield macular thickness (CSMT, microm) according to optical coherent tomography were assessed at baseline and 1, 3, and 6 months after an injection of TA. RESULTS: The patients included four men and 12 women with an average age of 56.9 years. VA improved significantly from 0.70 +/- 0.33 (mean +/- SD) before injection to 0.56 +/- 0.24 one month and 0.54 +/- 0.21 three months after an injection of TA. Visual acuity at six months was 0.61 +/- 0.24 and had no significance (p = 0.17). CSMT decreased significantly from 469 +/- 145 before injection to 323 +/- 58, 343 +/- 100, and 389 +/- 156 one, three, and six months after an injection of TA, respectively. CONCLUSIONS: Posterior subtenon injection of TA is effective in the short-term for improving VA and CMT in patients with refractory diabetic macular edema after vitrectomy.

Visual Field Defect Developed after Internal Limiting Membrane Peeling in a Patient with Epiretinal Membrane

PURPOSE: To report a case of visual field defect developed after internal limiting membrane (ILM) peeling in a patient with macular epiretinal membrane (ERM). CASE SUMMARY: A 33-year-old female without a history of specific diseases presented with a gradually decreased visual acuity in the right eye for 3 years. The patient was diagnosed as having macular ERM and underwent vitrectomy. During ILM peeling, retinal hemorrhage occurred in the superior region of macula, which spontaneously disappeared 2 weeks after surgery. Transmission electron microscopy showed Muller cell end feet with damaged appearance adherent to the ILM. At 3 months after surgery, the patient developed retinal nerve fiber layer (RNFL) defect in the area where the spot retinal hemorrhage had occurred. Optical coherence tomography showed focal RNFL thinning in the superotemporal region. The automated perimetry revealed corresponding inferior nasal step and scotomas in the right eye. Intraocular pressure was normal throughout the follow-up period and there was no evidence of glaucomatous optic disc change. CONCLUSIONS: The results obtained from the patient in the present study indicated that visual field defect may be the result of a mechanical damage to the RNFL during ILM peeling.

Ultrastructure of the Internal Limiting Membrane Removed During Macular Hole and Diabetic Macular Edema Surgery

PURPOSE: To evaluate retinal damage following internal limiting membrane (ILM) peeling in macular hole and diabetic macular edema (DME) surgeries. METHODS: Forty-five eyes with macular holes and thirty-five eyes with DME underwent pars plana vitrectomy with ILM peeling. The structures of the ILM were investigated using transmission electron microscopy, and the grades of retinal tissue damage were analyzed. We additionally observed the clinicopathologic association of retinal damage with the development of retinal hemorrhage during ILM peeling and that seen with indocyanine green (ICG) staining. RESULTS: In all specimens, cellular fragments were observed on the retinal side of the ILM in both macular hole and DME patients. The thickness of the ILM in DME significantly increased (3.13+/-1.12 micrometer compared with that in patients with macular holes (2.41+/-0.77 micrometer, p=0.002). The frequency of minute retinal bleeding during ILM peeling was higher in macular hole patients (46.7%) than in those with diabetic macular edema (22.9%m p=0.028). Twenty-two eyes of 45 macular hole patients (48.9%) and 16 eyes of 35 DME patients (45.7%) had relative retinal damage. Overall, ILM performed in eyes which had minute bleeding during the peeling had more retinal damage (62.1%) than did those without hemorrhage (39.2%, p=0.049). ICG staining did not appear to influence retinal damage (p=0.81). CONCLUSIONS: ILM peeling can cause minor, but demonstrable, damage of the adjacent retina.

Ultrastructural Investigation of the Retinal Changes in Diabetic Rat (OLETF)

PURPOSE: To compare retinal ultra-structures of diabetic rats (OLETF, Otsuka Long-Evans Tokushima Fatty) with those of agematched non-diabetic rats (LETO, Long-Evans Tokushima Otsuka) using transmission electron micrography (TEM). METHODS: The body weights and blood sugar levels of the OLETF rats and LETO rats (n=5) were measured at 10 and 50 weeks of age. Using a TEM, we compared the ultra-structural changes between the retinas of the 50-week-old OLETF and LETO rats. We analyzed the sizes of the pericytes and the thicknesses of the retinal capillary basement membranes between the two groups. Comparisons were made using a Scion Image(R). RESULTS: The mean body weight and blood sugar levels of the 50-week-old OLETF rats were significantly higher than those of the LETO rats (p(R)0.05). The thicknesses of the retinal capillary basement membranes in the outer plexiform layer and the size of pericytes were significantly increased in the OLETF rats at 50 weeks of age (p<0.05). The number of nuclei in the inner nuclear layer and the outer nuclear layer (photoreceptor cell nuclei) significantly decreased (p<0.05). However, the height of the RPE cells and basal in-foldings showed no significant differences between the OLETF and LETO rats. CONCLUSIONS: The retinal changes in the OLETF rats were observed relatively early at 50 weeks of age. These changes are similar to those seen in human diabetic retinopathy. Change in the capillaries is one feature of early retinal change. OLETF rats may be a useful animal model in NIDDM to examine diabetic retinal changes.