Short-term Outcomes and Prognostic Factors of iStent in the Republic of Korea

Purpose@#To evaluate the intraocular pressure (IOP) reduction, success rate and prognostic factors after trabecular micro-bypassstent implantation in patients with open-angle glaucoma. @*Methods@#We retrospectively reviewed 33 eyes of 33 patients with open-angle glaucoma who were followed-up for more than6 months after trabecular micro-bypass stent implantation. The success of surgery was defined as an IOP ≤ 21 mmHg and anIOP reduction ≥ 20% from baseline, regardless of whether glaucoma medication was used. @*Results@#During the follow-up at 6 months after trabecular micro-bypass stent implantation, the IOP was significantly decreasedfrom 23.70 ± 6.26 mmHg before surgery to 18.03 ± 4.64 mmHg after 6 months, and the glaucoma medication was significantlydecreased from 3.73 ± 0.67 before surgery to 3.43 ± 0.67 after 6 months (p < 0.001 and p = 0.027, respectively). The successrate at 6 months was 33.7 ± 5.5% in patients with only trabecular micro-bypass stent implantation. Using multiple regressionanalyses of the risk factors, age was associated with success rate (odds ratio, 1.076; 95% confidence interval, 0.996-1.164;p = 0.045). @*Conclusions@#In patients in the Republic of Korea, trabecular micro-bypass stent implantation was an effective surgery for IOPreduction, and showed a better surgical success rate in younger patients.

Bilateral Acute Angle Closure Attack and Choroidal Detachment in Patient with Acquired Immune Deficiency Syndrome

PURPOSE: To report a case of simultaneous bilateral acute angle closure attack combined with bilateral choroidal detachment in a patient with acquired immune deficiency syndrome (AIDS).CASE SUMMARY: A 63-year-old male who had a history of several months of diarrhea, abdominal pain, and weight loss visited the emergency room with sudden bilateral blurred vision accompanied with headache, periocular pain, nausea, and vomiting. His visual acuity was finger counting in both eyes and the intraocular pressure (IOP) was 49/44 mmHg (right/left). The anterior chamber depth was three times the corneal thickness in the center and less than 1/4 of the corneal thickness in the periphery in both eyes. Maximum medical therapy had no effect and emergency cataract surgery combined with vitrectomy was performed on the right eye. During surgery, severe choroidal detachment was noted. One day after surgery, choroidal detachment was also found in the left eye and emergency cataract surgery with suprachoroidal fluid drainage was performed. Approximately 1 month after surgery, choroidal detachment of both eyes regressed without systemic therapy. The IOP was 14/7 mmHg (right/left) with a visual acuity of 0.32/0.4 (right/left). The blood test performed in the emergency room showed a positive result for AIDS and the patient started medical therapy.CONCLUSIONS: In patients with AIDS, bilateral simultaneous acute angle closure attack combined with choroidal detachment may rarely develop. Although choroidal effusion can regress spontaneously, combined suprachoroidal fluid drainage is recommended when a surgical intervention is required.

The Shortest Radius of Curvature of Bruch's Membrane in Macular Optical Coherence Tomography

PURPOSE: To develop software to measure the shortest radius in curvature of Bruch's membrane from optical coherence tomography (OCT), and then to apply it to various types of eyes. METHODS: Macular OCT images consisting of 12 images of 9 mm radial scans were studied. The horizontal to vertical pixel ratios were changed to 1:1, and Bruch's membrane was marked automatically on each image. Software to measure the radius of Bruch's membrane curvature was developed. The shortest radius on each image was defined as r (mm) and the average r of 12 images was defined as R (mm). The reciprocal of R was multiplied by the constant, 337.5, which was defined as the posterior staphyloma (PS) index. RESULTS: The OCT images of five eyes were analyzed by the software, which could calculate the curvature of Bruch's membrane automatically. The PS indices were 12.7, 23.7, and 66.4 in eyes without refractive error (Case I), in the high myopic group without posterior staphyloma (Case II), and in the high myopic group with posterior staphyloma (Case V), respectively. The PS index gradually increased according to aging in a 37-year-old patient (Case IV) with mild staphyloma from 34.6 to 39.5 over 4 years. CONCLUSIONS: PS index is a novel parameter to reflect the level of posterior staphyloma, but further studies are needed to apply it to clinical patients.

Vascular Displacement in Idiopathic Macular Hole after Single-layered Inverted Internal Limiting Membrane Flap Surgery

PURPOSE: To compare vascular displacement in the macula after surgical closure of idiopathic macular hole (MH) after single-layered inverted internal limiting membrane (ILM) flap technique and conventional ILM removal. METHODS: This retrospective study included patients who underwent either vitrectomy and ILM removal only or vitrectomy with single-layered inverted ILM flap for idiopathic MH larger than 400 µm from 2012 to 2015. A customized program compared the positions of the retinal vessels in the macula between preoperative and postoperative photographs. En face images of 6 × 6 mm optical coherence tomography volume scans were registered to calculate the scale. Retinal vessel displacement was measured as a vector value by comparing its location in 16 sectors of a grid partitioned into eight sectors in two rings (inner, 2 to 4 mm; outer, 4 to 6 mm). The distance and angle of displacement were calculated as an average vector and were compared between the two groups for whole sectors, inner ring, outer ring, and for each sector. RESULTS: Twenty patients were included in the ILM flap group and 22 in the ILM removal group. There were no statistical differences between the groups for baseline characteristics. The average displacement in the ILM flap group and the ILM removal group was 56.6 µm at −3.4° and 64.9 µm at −2.7°, respectively, for the whole sectors (p = 0.900), 76.1 µm at −1.1° and 87.3 µm at −0.9° for the inner ring (p = 0.980), and 37.4 µm at −8.2° and 42.7 µm at −6.3° for the outer ring (p = 0.314). There was no statistical difference in the displacement of each of the sectors. CONCLUSIONS: Postoperative topographic changes showed no significant differences between the ILM flap and the ILM removal group for idiopathic MH. The single-layered ILM flap technique did not appear to cause additional displacement of the retinal vessels in the macula.

Diagnostic Accuracies of Bruch Membrane Opening-minimum Rim Width and Retinal Nerve Fiber Layer Thickness in Glaucoma

PURPOSE: To compare the diagnostic capability of Bruch membrane opening-minimum rim width (BMO-MRW) and peripapillary retinal nerve fiber layer (RNFL) thickness for the detection of primary open angle glaucoma. METHODS: Spectral-domain optical coherence tomography (SD-OCT) with 24 radial and 1 peripapillary B-scans centered on the Bruch membrane opening (BMO) was performed. Two SD-OCT parameters were computed globally and sectorally: (1) BMO-MRW, the minimum distance between BMO and internal limiting membrane; and (2) peripapillary retinal nerve fiber layer (RNFL) thickness. The diagnostic performance of BMO-MRW and RNFL thickness were compared with receiver operating characteristic (ROC) analysis globally and sectorally. Areas under the ROC (AUC) were calculated and compared. RESULTS: One hundred fourteen eyes (52 healthy, 62 glaucomatous) of 114 participants were included. In global analyses, the performance of BMO-MRW was similar to that of RNFL thickness (AUC 0.95 [95% confidence interval {CI}, 0.91-0.99], and 0.95 [95% CI, 0.91-0.99], respectively, p=0.93). In sectoral analyses, the pair-wise comparison among the ROC curves showed no statistical difference for all sectors except for the superotemporal, superonasal, and nasal sectors, which had significantly larger AUCs in BMO-MRW compared to RNFL thickness (p=0.03, p<0.001, and p=0.03, respectively). The parameter with the largest AUC was the inferotemporal sector for both BMO-MRW and RNFL thickness (AUC 0.98 [95% CI, 0.96-1.00], and 0.98 [95% CI, 0.96-1.00], respectively, p=0.99). CONCLUSIONS: Global BMO-MRW performed as well as global RNFL thickness for detection of glaucoma. In superotemporal, superonasal and nasal sectors, regional BMO-MRW performed better than regional RNFL thickness.

Intravitreal Bevacizumab and Subsequent Trabeculectomy with Mitomycin C for Neovascular Glaucoma with Previous Sutureless Vitrectomy

PURPOSE: To evaluate the efficacy of intravitreal bevacizumab and subsequent trabeculectomy with mitomycin C (MMC) for neovascular glaucoma (NVG) in eyes that underwent previous 23-gauge transconjunctival sutureless vitrectomy (TSV). METHODS: This was a retrospective, comparative, and consecutive case series study. We reviewed the medical records of patients with NVG who underwent trabeculectomy with MMC after intravitreal bevacizumab (1.25 mg/0.05 mL) injection and compared the surgical outcomes according to 23-gauge TSV history. Surgical success was defined as an intraocular pressure (IOP) of ≥6 mm Hg and ≤21 mm Hg without additional glaucoma surgery or loss of light perception. The main outcome measures were postoperative IOP control, visual acuity, and complications. RESULTS: A total of 27 patients (27 eyes) were included; 12 patients with 23-gauge TSV history (TSV group) and 15 patients without vitrectomy history (nonvitrectomized group). The cumulative probability of success after trabeculectomy with MMC was 82.5% and 73.3% after one year for the TSV group and the nonvitrectomized group, respectively (p = 0.523). Mean IOP decreased from 37.3 ± 9.0 mm Hg preoperatively to 12.8 ± 6.2 mmHg at the final visit in the TSV group (p = 0.002). Mean IOP decreased from 40.3 ± 9.7 mm Hg preoperatively to 17.8 ± 11.7 mm Hg at the final visit in the nonvitrectomized group (p = 0.001). Preoperative and final IOP were not significantly different between the two groups. Complications were comparable between the groups. CONCLUSIONS: Intravitreal bevacizumab injection and subsequent trabeculectomy with MMC is an effective method for controlling IOP in patients with NVG associated with sutureless vitrectomy.

Intravitreal Bevacizumab and Subsequent Trabeculectomy with Mitomycin C for Neovascular Glaucoma with Previous Sutureless Vitrectomy

PURPOSE: To evaluate the efficacy of intravitreal bevacizumab and subsequent trabeculectomy with mitomycin C (MMC) for neovascular glaucoma (NVG) in eyes that underwent previous 23-gauge transconjunctival sutureless vitrectomy (TSV). METHODS: This was a retrospective, comparative, and consecutive case series study. We reviewed the medical records of patients with NVG who underwent trabeculectomy with MMC after intravitreal bevacizumab (1.25 mg/0.05 mL) injection and compared the surgical outcomes according to 23-gauge TSV history. Surgical success was defined as an intraocular pressure (IOP) of ≥6 mm Hg and ≤21 mm Hg without additional glaucoma surgery or loss of light perception. The main outcome measures were postoperative IOP control, visual acuity, and complications. RESULTS: A total of 27 patients (27 eyes) were included; 12 patients with 23-gauge TSV history (TSV group) and 15 patients without vitrectomy history (nonvitrectomized group). The cumulative probability of success after trabeculectomy with MMC was 82.5% and 73.3% after one year for the TSV group and the nonvitrectomized group, respectively (p = 0.523). Mean IOP decreased from 37.3 ± 9.0 mm Hg preoperatively to 12.8 ± 6.2 mmHg at the final visit in the TSV group (p = 0.002). Mean IOP decreased from 40.3 ± 9.7 mm Hg preoperatively to 17.8 ± 11.7 mm Hg at the final visit in the nonvitrectomized group (p = 0.001). Preoperative and final IOP were not significantly different between the two groups. Complications were comparable between the groups. CONCLUSIONS: Intravitreal bevacizumab injection and subsequent trabeculectomy with MMC is an effective method for controlling IOP in patients with NVG associated with sutureless vitrectomy.

The Clinical Efficacy of the Haigis Formula Using A-Scan Contact Ultrasound Biometry

PURPOSE: To investigate the accuracy of the Haigis formula compared to other formulas using contact ultrasound biometry. METHODS: This study was performed on 94 patients (114 eyes) who underwent cataract surgery in our hospital. Axial length (AXL) and anterior chamber depth (ACD) were measured using both A-scan and intraocular lens (IOL) Master(R). Patients were divided into three groups based on AXL; Group I (AXL or = 25.5 mm). Before cataract surgery, predicted refraction was calculated using the Haigis, SRK/T, Hoffer Q, and Holladay 1 formulas using both A-scan and IOL Master(R) measurements. Mean absolute error (MAE) were analyzed at one month after surgery using the various IOL formulas. RESULTS: Using contact ultrasound biometry, in Group I, MAE of Haigis was 0.80 +/- 0.67 D and was significantly lower than that using SRK/T. In Group II, the Haigis MAE was 0.72 +/- 0.55 D and was significantly lower than the results of all other formulas. In Group III, the Haigis MAE was 0.76 +/- 1.13 D and not significantly different from the results of other formulas. Comparing MAE of A-scan to IOL Master(R), the Haigis formula showed 0.16 D higher error that decreased when the AXL was close to the normal range. CONCLUSIONS: Using contact ultrasound biometry, the Haigis formula provided the best predictability of postoperative refractive outcome compared to other formulas in eyes with normal axial length.

The Clinical Efficacy of the Haigis Formula Using A-Scan Contact Ultrasound Biometry

PURPOSE: To investigate the accuracy of the Haigis formula compared to other formulas using contact ultrasound biometry. METHODS: This study was performed on 94 patients (114 eyes) who underwent cataract surgery in our hospital. Axial length (AXL) and anterior chamber depth (ACD) were measured using both A-scan and intraocular lens (IOL) Master(R). Patients were divided into three groups based on AXL; Group I (AXL or = 25.5 mm). Before cataract surgery, predicted refraction was calculated using the Haigis, SRK/T, Hoffer Q, and Holladay 1 formulas using both A-scan and IOL Master(R) measurements. Mean absolute error (MAE) were analyzed at one month after surgery using the various IOL formulas. RESULTS: Using contact ultrasound biometry, in Group I, MAE of Haigis was 0.80 +/- 0.67 D and was significantly lower than that using SRK/T. In Group II, the Haigis MAE was 0.72 +/- 0.55 D and was significantly lower than the results of all other formulas. In Group III, the Haigis MAE was 0.76 +/- 1.13 D and not significantly different from the results of other formulas. Comparing MAE of A-scan to IOL Master(R), the Haigis formula showed 0.16 D higher error that decreased when the AXL was close to the normal range. CONCLUSIONS: Using contact ultrasound biometry, the Haigis formula provided the best predictability of postoperative refractive outcome compared to other formulas in eyes with normal axial length.