Alcohol-assisted debridement in PRK with intraoperative mitomycin C.

PURPOSE: To compare corneal stromal and endothelial cells after photorefractive keratectomy with intraoperative mitomycin C in alcohol-assisted versus mechanical epithelial debridement using confocal microscopy. METHODS: This prospective randomized comparative study was performed on 88 eyes (44 patients) with myopia up to -6.00 diopters. The right eye of each patient was randomly assigned to either mechanical or alcohol-assisted groups, and the left eye was assigned to the alternate group. Confocal microscopy was performed preoperatively and at 3 months postoperatively. The main outcome measures were epithelial thickness; number of keratocytes in the anterior, mid-, and posterior stroma; and characteristics of the central corneal endothelial cells in terms of density, mean cell area, and polymegathism and hexagonality. RESULTS: Three months after surgery, no statistically significant difference was noted between the study groups in terms of epithelial thickness. We also found no statistically significant difference in central corneal endothelial cells regarding cell density, mean cell area, hexagonality, or polymegathism. Compared with baseline values, the density of mid- and posterior stromal keratocytes showed no significant change in either group, whereas it decreased significantly in the anterior stroma in both groups 3 months after surgery. CONCLUSIONS: We found that the adverse effects of photorefractive keratectomy with mitomycin C on central corneal endothelial cells were comparable between the mechanical and alcohol-assisted epithelial debridement groups and the significant decrease in postoperative keratocyte density in anterior stroma was comparable between the two groups. The choice of their application could be left to the discretion of the ophthalmologist.

Erythropoietin levels in aqueous humor of patients with glaucoma.

PURPOSE: To compare the aqueous concentration of erythropoietin (EPO) in eyes with primary open-angle (POAG), pseudoexfoliative (PXFG), and neovascular (NVG) glaucoma with age-matched eyes with cataracts, and to correlate its concentration with other factors including age, gender, intraocular pressure (IOP), type of glaucoma, and severity of glaucoma. METHODS: In this prospective non-randomized comparative study, a total of 26 eyes with cataracts (control group) and 92 glaucomatous eyes (POAG, 40 eyes; PXFG, 26 eyes; NVG, 26 eyes) were enrolled. Aqueous samples (0.1 to 0.2 ml) were obtained during phacoemulsification, trabeculectomy, phacotrabeculectomy, or Ahmed valve glaucoma implants. The aqueous concentration of EPO was measured using an enzyme-linked immunosorbent assay. RESULTS: The mean±SEM aqueous level of EPO was statistically significantly higher in eyes with glaucoma (56.7±9.3 mIU/ml) compared to the control group (0.8±0.51 mIU/ml; p<0.001). Eyes with NVG had the highest aqueous level of EPO. Aqueous EPO concentrations remained considerably elevated even in eyes with controlled IOP in all three types of glaucoma. Eyes with PXFG displayed the greatest change in aqueous EPO concentration proportionate to the IOP level. In simple regression analysis, IOP, mean deviation, and the type of glaucoma were the factors that had a statistically significantly positive correlation with the aqueous level of EPO (p=0.011 and <0.001, respectively). Only the type of glaucoma remained statistically significant in the multiple regression analysis (adjusted R(2)=0.278). CONCLUSIONS: Compared to the control group, the aqueous humor EPO concentration is increased in eyes with POAG, PXFG, and NVG, both with and without controlled IOP. The aqueous level of EPO was more proportionate to the level of IOP in eyes with PXFG compared to eyes with POAG and NVG.

Finite element analysis of blunt foreign body impact on the cornea after PRK and LASIK.

PURPOSE: To investigate the effect of blunt foreign body impact on a human cornea after photorefractive keratectomy (PRK) and LASIK using a simulation model. METHODS: Computational simulations were performed using a finite element analysis program (LS-Dyna, Livermore Software Technology Corp). The blunt foreign body was set to impact at the center of the corneal surface models (after PRK and LASIK) with thicknesses of 500, 450, 400, 350, and 300 µm. Corneal rupture was assumed to occur at a peak stress of 9.45 MPa and at a strain of 18%. The foreign body projectile was blunt in shape, made from aluminum, contained plastic-kinematic properties, and had a density of 2700 kg/m(3). RESULTS: The projectile was launched at the center of the cornea with velocities ranging from 20 to 60 m/s. The threshold of impact velocities creating rupture in corneal thicknesses of 500, 450, 400, 350, and 300 µm were 33, 32.8, 30.7, 27.9, and 22.8 m/s, respectively, in the PRK model. In the LASIK model, the thresholds creating rupture in the stromal bed of the corneas with thicknesses of 500, 450, 400, 350, and 300 µm were 40, 38.1, 35.6, 31.5, and 26.7 m/s, respectively. The 110-µm corneal flap in the LASIK model ruptured at all velocities. CONCLUSIONS: Ruptures occurred at lower velocities in the PRK cornea model than in the corneal stromal bed of the LASIK model following blunt foreign body impact.

Is post-trabeculectomy serous choroidal detachment a risk factor for failure in the long term.

BACKGROUND: To investigate the long-term effect of serous choroidal detachment on the success of trabeculectomy in glaucoma patients. METHODS: In this case-control study, 17 patients who underwent trabeculectomy and developed choroidal detachment, and completed at least 3 years of follow-up were included. The controls were matched based on age, sex, preoperative intraocular pressure, and glaucoma type, and lack of choroidal detachment. Surgical success was defined based on two definitions of 5 < IOP < 16 and 20% reduction from the baseline and no need for further glaucoma surgery and all the same but 5 < IOP < 22. RESULTS: The mean estimated duration of survival ±SD was 2.73 ± 0.35 years (CI 95% 2.1, 3.4), which was significantly shorter than 3.98 ± 0.38 years (CI 95% 3.3, 4.7) in the control group. (LogRank = 5.03 p = 0.02). Cumulative probability of success was 76.5%, 52.9%, 29.4%, 17.6%, and 11.8% in year 1, 2, 3, 4, and 5 in the case group, respectively. Corresponding values were 88.2%, 82.4%, 68.6%, 58.8%, and 47.1%. In the control group, respectively. At baseline, average IOP was 22.3 ± 2.7 and 23.8 ± 8.3 mmHg in the case and control groups, respectively (p = 0.17). Mean IOP was significantly higher in the case group than in the control group in years 2, 3, 4, and 5. CONCLUSION: Serous choroidal detachment affects the long-term surgical success of trabeculectomy, especially in patients with advanced glaucoma when lower target pressure is required.

Comparison of 2 surgical techniques in phacotrabeculectomy: 1 site versus 2 sites.

PURPOSE: To compare 1-site and 2-site phacotrabeculectomies with regard to visual acuity, intraocular pressure (IOP) control, antiglaucoma medication requirements, and postoperative complications. METHODS: In a randomized controlled trial, 169 eyes with coexisting visually significant cataract and glaucoma were randomly allocated into 2 groups: eyes that had a trabeculectomy in a superior quadrant combined with phacoemulsification through the same incision (1-site group; n=85) or those with a separate, temporal, clear corneal incision for phacoemulsification (2-site group; n=84). Postoperative evaluation, including visual acuity, intraocular pressure (IOP), glaucoma medication requirements, and surgical complications, was for up to 18 months. RESULTS: After 18 months, there was no significant difference between the 2 groups with respect to visual acuity and antiglaucoma medication requirements. There was a 0.6 to 1.4 mmHg difference in mean IOP, with the 2-site technique demonstrating statistically significant advantage over the 1-site technique in some follow-up visits with nonparametric analysis; however, the difference cannot be clinically significant. Success rates (IOP<21 mmHg with the maximum use of medication) of 1-site and 2-site groups were 85.9% and 92.8%, respectively, which was not statistically significant (p=0.153). Nevertheless, the incidence of failure in the 1-site group was almost twice that of the 2-site group (12 vs 6). Postoperative complications were comparable in both groups. CONCLUSIONS: Results for 18-month follow-ups of 1-site and 2-site phacotrabeculectomies were comparable in terms of visual acuity, antiglaucoma medication requirements, and postoperative complications. While lowering of IOP was more pronounced in the 2-site group, this was not clinically significant.

Comparative Assessment of Tear Function Tests, Tear Osmolarity, and Conjunctival Impression Cytology between Patients with Pterygium and Healthy Eyes.

PURPOSE: To compare histologic abnormalities of tear film and tear osmolarity between normal eyes and eyes with pterygium. METHODS: This was a prospective, hospital-based, case-control study involving 95 patients (65 men, 30 women) with unilateral pterygium. The tear meniscus height (TMH), Schirmer's test-1 (SCH-1) score, Rose Bengal staining (RBS) score, tear film breakup time (TBUT), tear osmolarity (TO), and conjunctival impression cytology (CIC) were assessed in both eyes. The Chi-square and Student's t-tests were used to compare the results between the two groups. P values <0.05 were considered statistically significant. RESULTS: The mean patient age was 50.9 years, with the largest age group being the 45-55 year-old bracket across both genders. Most patients (82.1%) had nasal pterygium, and 80% were involved in outside activities. The mean assessment values in the case and control groups were as follows: TMH, 0.21 vs. 0.24 mm; SCH-1, 13.2 vs. 17.8 mm; RBS, 4.38 vs. 2.51 points; TBUT, 8.7 vs. 13.2 seconds; TO, 306 vs. 299 mOsm/L (P < 0.001 in all cases). The proportions of abnormal assessment values in the case and control groups were as follows: TMH, 82.1% vs. 3.16%; SCH-1, 20% vs. 2.1%; RBS, 30.53% vs. 4.22%; TBUT, 61.05% vs. 6.3%; TO, 10.52% vs. 1.05%; CIC, 33.7% vs. 7.37% (P < 0.05 for all comparisons). CONCLUSION: This study showed that the quantity and quality of tear film, as well as the number of goblet cells, decreased, but the tear osmolarity increased in eyes with pterygium. Furthermore, the TMH, RBS results, TBUT, and CIC have more precise state of the patient's tear condition with the disease of the pterygium.

Corneal endothelial cell injury induced by mitomycin-C in photorefractive keratectomy: nonrandomized controlled trial.

PURPOSE: To evaluate the effect of intraoperative use of mitomycin-C (MMC) on the corneal endothelium during excimer laser photorefractive keratectomy (PRK). SETTING: Vanak Eye Surgery Center, Tehran, Iran. METHODS: This nonrandomized trial comprised 81 patients (162 eyes) with bilateral low to moderate myopia and adequate corneal thickness to allow PRK (estimated postoperative residual stromal thickness >350 microm without considering epithelial thickness). The indication for intraoperative application of MMC 0.02% (0.2 mg/mL) was an ablation depth of 75 microm or more. Patients were divided into 3 groups: bilateral (both eyes treated with MMC), unilateral (only 1 eye treated with MMC), and untreated (no eye treated with MMC). Visual acuity, refraction, endothelial cell density (ECD), and corneal thickness were measured preoperatively as well as 1 week and 1, 3, and 6 months postoperatively. RESULTS: Overall, 76 eyes were treated with MMC. Eyes treated with MMC and untreated eyes were comparable in postoperative visual acuity and refraction. Preoperative to postoperative changes in ECD were statistically significantly greater in the treated eyes (-14.8%) than in untreated eyes (-5.1%) 6 months after PRK (P<.001). Longer MMC contact time (P<.001) and male sex (P= .04) were the only factors independently associated with greater endothelial cell loss. CONCLUSIONS: The prophylactic use of diluted intraoperative MMC 0.02% solution caused corneal endothelial cell loss. The rate of cell loss was correlated with the duration of MMC exposure.

Visual acuity, endothelial cell density and polymegathism after iris-fixated lens implantation.

PURPOSE: The purpose of this study was to evaluate the visual acuity as well as endothelial cell density (ECD) and polymegathism after iris-fixated lens (Artiflex® AC 401) implantation for correction of moderate to high myopia. PATIENTS AND METHODS: In this retrospective cross-sectional study, 55 eyes from 29 patients undergoing iris-fixated lens implantation for correction of myopia (-5.00 to -15.00 D) from 2007 to 2014 were evaluated. Uncorrected visual acuity, best spectacle-corrected visual acuity, refraction, ECD and polymegathism (coefficient of variation [CV] in the sizes of endothelial cells) were measured preoperatively and 6 months postoperatively. RESULTS: In the sixth month of follow-up, the uncorrected vision acuity was 20/25 or better in 81.5% of the eyes. The best-corrected visual acuity was 20/30 or better in 96.3% of the eyes, and more than 92% of the eyes had a refraction score of ±1 D from the target refraction. The mean corneal ECD of patients before surgery was 2,803±339 cells/mm2, which changed to 2,744±369 cells/mm2 six months after surgery (p=0.142). CV in the sizes of endothelial cells before the surgery was 25.7%±7.1% and six months after surgery it was 25.9%±5.4% (p=0.857). CONCLUSION: Artiflex iris-fixated lens implantation is a suitable and predictable method for correction of moderate to high myopia. There was no statistically significant change in ECD and polymegathism (CV in the sizes of endothelial cells) after 6 months of follow-up.

Vitamin B12 Deficiency as a Cause of Neurotrophic Keratopathy.

INTRODUCTION: Neurotrophic keratitis is a rare degenerative corneal disease caused by an impairment of trigeminal corneal innervation, leading to a decrease or absence of corneal sensation. Here, we present a case of neurotrophic keratopathy caused by B12 deficiency in a 34 years old man who had a progressive decrease in visual acuity and corneal involvement since 3 months before being referred to our ophthalmology clinic. RESULT AND DISCUSSION: Based on our clinical findings and with the diagnosis of B12 deficiency we started B12 treatment for the patient. After 3 weeks the patient showed a dramatic response with corneal sensation reversal, an increase of visual acuity, improved neurotrophic keratopathy and significantly improved neurological findings. To the best of our knowledge, there is no report regarding vitamin B12 deficiency induced keratopathy and this is the first report that describes this aspect of vitamin B12 deficiency.

Screening for MIR184 Mutations in Iranian Patients with Keratoconus.

PURPOSE: To investigate whether microRNA (MIR)-184 mutations make a substantial contribution to keratoconus (KCN) among affected Iranian patients. METHODS: A total of 47 Iranian KCN patients, diagnosed based on family history, clinical examinations using slit lamp biomicroscopy, refraction and corneal topography were enrolled in this study. The pri-miR-184 encoding gene obtained from the DNAs of all participants was amplified using polymerase chain reaction and subsequently sequenced by the Sanger dideoxynucleotide protocol. The sequences were compared to MIR184 reference sequence in order to identify sequence variations. The potential effects of a single variation observed on RNA structure was predicted. RESULTS: Only one sequence variation, +39G >T, was observed within the pri-miR-184 encoding sequence in one proband. The patient's KCN-affected sister harbored the same variation. The variation was not novel and was recently shown to be present at similar frequencies among large cohorts of KCN patients and control individuals. CONCLUSION: Mutations in MIR-184 are not a major cause of keratoconus among Iranian patients. The pri-miR-184 sequence needs to be screened in larger cohorts in order to establish whether mutations in the gene are present at low frequencies among Iranian patients.

Refractive Outcomes, Contrast Sensitivity, HOAs, and Patient Satisfaction in Moderate Myopia: Wavefront-Optimized Versus Tissue-Saving PRK.

PURPOSE: To compare refractive outcomes, contrast sensitivity, higher-order aberrations (HOAs), and patient satisfaction after photorefractive keratectomy for correction of moderate myopia with two methods: tissue saving versus wavefront optimized. METHODS: In this prospective, comparative study, 152 eyes (80 patients) with moderate myopia with and without astigmatism were randomly divided into two groups: the tissue-saving group (Technolas 217z Zyoptix laser; Bausch & Lomb, Rochester, NY) (76 eyes of 39 patients) or the wavefront-optimized group (WaveLight Allegretto Wave Eye-Q laser; Alcon Laboratories, Inc., Fort Worth, TX) (76 eyes of 41 patients). Preoperative and 3-month postoperative refractive outcomes, contrast sensitivity, HOAs, and patient satisfaction were compared between the two groups. RESULTS: The mean spherical equivalent was -4.50 ± 1.02 diopters. No statistically significant differences were detected between the groups in terms of uncorrected and corrected distance visual acuity and spherical equivalent preoperatively and 3 months postoperatively. No statistically significant differences were seen in the amount of preoperative to postoperative contrast sensitivity changes between the two groups in photopic and mesopic conditions. HOAs and Q factor increased in both groups postoperatively (P = .001), with the tissue-saving method causing more increases in HOAs (P = .007) and Q factor (P = .039). Patient satisfaction was comparable between both groups. CONCLUSIONS: Both platforms were effective in correcting moderate myopia with or without astigmatism. No difference in refractive outcome, contrast sensitivity changes, and patient satisfaction between the groups was observed. Postoperatively, the tissue-saving method caused a higher increase in HOAs and Q factor compared to the wavefront-optimized method, which could be due to larger optical zone sizes in the tissue-saving group.

Customized Clinical Practice Guidelines for Management of Adult Cataract in Iran.

PURPOSE: To customize clinical practice guidelines (CPGs) for cataract management in the Iranian population. METHODS: First, four CPGs (American Academy of Ophthalmology 2006 and 2011, Royal College of Ophthalmologists 2010, and Canadian Ophthalmological Society 2008) were selected from a number of available CPGs in the literature for cataract management. All recommendations of these guidelines, together with their references, were studied. Each recommendation was summarized in 4 tables. The first table showed the recommendation itself in clinical question components format along with its level of evidence. The second table contained structured abstracts of supporting articles related to the clinical question with their levels of evidence. The third table included the customized recommendation of the internal group respecting its clinical advantage, cost, and complications. In the fourth table, the internal group their recommendations from 1 to 9 based on the customizing capability of the recommendation (applicability, acceptability, external validity). Finally, customized recommendations were sent one month prior to a consensus session to faculty members of all universities across the country asking for their comments on recommendations. RESULTS: The agreed recommendations were accepted as conclusive while those with no agreement were discussed at the consensus session. Finally, all customized recommendations were codified as 80 recommendations along with their sources and levels of evidence for the Iranian population. CONCLUSION: Customization of CPGs for management of adult cataract for the Iranian population seems to be useful for standardization of referral, diagnosis and treatment of patients.

Central Corneal Thickness in Highly Myopic Eyes: Inter-device Agreement of Ultrasonic Pachymetry, Pentacam and Orbscan II Before and After Photorefractive Keratectomy.

PURPOSE: To determine inter-device agreement for central corneal thickness (CCT) measurement among ultrasound pachymetry, rotating Scheimpflug imaging (Pentacam, Oculus, Wetzlar, Germany), and scanning slit corneal topography (Orbscan II, Bausch & Lomb, Rochester, NY, USA) in highly myopic eyes before and after photorefractive keratectomy (PRK). METHODS: This prospective comparative study included 61 eyes of 32 patients with high myopia who underwent PRK. Six month postoperative CCT values were compared to preoperative values in 27 patients (51 eyes) who completed the follow up period. To determine the level of agreement, Pentacam and Orbscan II readings were compared to ultrasonic pachymetry measurements as the gold standard method. RESULTS: Mean CCT measurements with ultrasound, Pentacam, and Orbscan II before PRK were 557µm, 556µm, and 564µm, respectively; and 451µm, 447µm, and 438µm 6 months after surgery in the same order. Preoperatively, the 95% limits of agreement (LoA) with ultrasound measurements were -20µm to 17µm for Pentacam and -21µm to 33µm for Orbscan II. Six months postoperatively, the 95% LoA were -30µm to 23µm for Pentacam and -69µm to 43µm for Orbscan II. CONCLUSION: Preoperatively, CCT measurements were higher with Orbscan II as compared to ultrasound. Postoperatively, both Pentacam and Orbscan II measurements were lower than those obtained with ultrasound, but Pentacam had better agreement. The use of ultrasound, as the gold standard method, or Pentacam both appear to be preferable over Orbscan II among patients with high myopia.

Orthoptic Changes following Photorefractive Keratectomy.

PURPOSE: To report orthoptic changes after photorefractive keratectomy (PRK). METHODS: This interventional case series included 297 eyes of 150 patients scheduled for PRK. Complete ophthalmologic evaluations focusing on orthoptic examinations were performed before and 3 months after PRK. RESULTS: Before PRK, 2 (1.3%) patients had esotropia which remained unchanged; 3 (2%) patients had far exotropia which improved after the procedure. Of 12 cases (8%) with initial exotropia at near, 3 (2%) cases became orthophoric, however 6 patients (4%) developed new near exotropia. A significant reduction in convergence and divergence amplitudes (P < 0.001) and a significant increase in near point of convergence (NPC) (P < 0.006) were noticed after PRK. A reduction ≥ 10 PD in convergence amplitude and ≥ 5 PD in divergence amplitude occurred in 10 and 5 patients, respectively. Four patients had initial NPC > 10 cm which remained unchanged after surgery. Out of 9 (6%) patients with baseline stereopsis > 60 seconds of arc, 2 (1.33%) showed an improvement in stereopsis following PRK. No patient developed diplopia postoperatively. CONCLUSION: Preexisting strabismus may improve or remain unchanged after PRK, and new deviations can develop following the procedure. A decrease in fusional amplitudes, an increase in NPC, and an improvement in stereopsis may also occur after PRK. Preoperative evaluation of orthoptic status for detection of baseline abnormalities and identification of susceptible patients seem advisable.

Corneal endothelial cell changes after Ahmed valve and Molteno glaucoma implants.

BACKGROUND AND OBJECTIVE: Changes in corneal endothelial cell (CEC) indices 24 months after Ahmed valve (New World Medical, Inc., Rancho Cucamonga, CA) and single-plate Molteno implants (Molteno Ophthalmic Limited, Dunedin, New Zealand) were evaluated. PATIENTS AND METHODS: This cohort included Ahmed valve (29 eyes) or single-plate Molteno (28 eyes) implants. Preoperative and postoperative central CEC indices were compared. Main outcome measure was endothelial cell count. RESULTS: Twenty-four months postoperatively, no difference in visual acuity improvement or decrease in antiglaucoma medications was observed between groups. The Molteno group showed better postoperative intraocular pressure control (P < .001). An 11.52% (Ahmed) and 12.37% (Molteno) reduction in CEC density (cells/mm(2)) and 3.78 (Ahmed) and 2.48 (Molteno) increase in CEC area (mm(2)) was observed, but no significant between-group difference in CEC density and area or corneal thickness. CONCLUSION: Twenty-four months after Ahmed valve or Molteno implant, statistically significant quantitative (cell density) and minor qualitative (cell area) changes in central CEC were observed. Both groups appeared to have similar CEC damage.

Visual outcome and contrast sensitivity after photorefractive keratectomy in low to moderate myopia: wavefront-optimized versus conventional methods.

PURPOSE: To compare visual outcomes and contrast sensitivity after wavefront-optimized or conventional photorefractive keratectomy (PRK) in myopic patients with or without astigmatism. SETTING: Vanak Eye Surgery Center, Tehran, Iran. DESIGN: Comparative case series. METHODS: Patients with low to moderate myopia with or without astigmatism were allocated into 2 groups. The study group was treated with wavefront-optimized PRK (Allegretto Wave Eye-Q software version 2.020 default treatment) and the control group, with conventional PRK (Technolas 217z). In all cases, treatments were bilateral and performed with the same device. Baseline and 3-month postoperative measures were uncorrected and corrected distance visual acuities, manifest refraction, and contrast sensitivity. RESULTS: Each group comprised 66 eyes. The mean preoperative spherical equivalent refraction improved from -2.99 diopters (D) ± 1.02 (SD) preoperatively to -0.08 ± 0.26 D 3 months postoperatively in the study group and from -2.66 ± 0.95 D to 0.01 ± 0.30 D, respectively, in the control group. In both groups, the postoperative mesopic and photopic contrast sensitivity decreased significantly at most spatial frequencies. The postoperative decrease in contrast sensitivity in both groups was comparable except at spatial frequencies of 3 cycles per degree (cpd) under mesopic conditions and 12 cpd under photopic conditions, frequencies at which the control group had a greater reduction. CONCLUSIONS: Visual acuity and refractive error outcomes were similar in both treatment groups. After 3 months, mesopic and photopic contrast sensitivity were significantly decreased in both groups; the reduction in the 2 groups was almost comparable. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Ahmed glaucoma valve and single-plate Molteno implants in treatment of refractory glaucoma: a comparative study.

PURPOSE: To report 2-year follow-up data after Ahmed valve implantation (New World Medical, Inc) and Molteno single-plate implantation surgical treatment of refractory glaucoma. DESIGN: Prospective, randomized, comparative study. METHODS: Patients with refractory glaucoma, defined as uncontrolled intraocular pressure (IOP) of more than 21 mm Hg despite maximal antiglaucoma medication, previously failed nonseton surgical treatment, or a combination thereof were included. Ninety-two patients were allocated randomly to each of the study groups and underwent implantation of either the Ahmed valve implant (model FP7; 184 mm(2) surface area) or Molteno single-plate implant (134 mm(2) surface area) and were followed up for 24 months. Main outcome measures were IOP and surgical success rate. Other outcome measures were changes in visual acuity, number of ant-glaucoma medications, mean deviation of visual field, and rate of intraoperative and postoperative complications. RESULTS: Those who successfully completed the trial (28 in the Molteno group and 29 in the Ahmed group) achieved significantly less IOP and fewer glaucoma medications, but worse visual acuity 24 months after surgery. The Molteno group, compared with the Ahmed group, achieved significantly lower IOPs after the early postoperative period until the end of the study. Both groups reasonably maintained visual field during the follow-up. The rate of surgical failure was comparable in both groups. Median survival time was 24 months for both groups. There were no devastating intraoperative or postoperative complications in either group. CONCLUSIONS: Both Ahmed and Molteno implants successfully preserved visual field, although IOP control was more pronounced in the Molteno implant group.

A comparison of corneal endothelial cell changes after 1-site and 2-site phacotrabeculectomy.

PURPOSE: To compare the corneal endothelial cell (CEC) changes that occurred after phacotrabeculectomy performed at 1 or 2 sites. DESIGN: A historical cohort study. METHODS: The records of patients who had 1-site (n = 61) or 2-site (n = 52) limbus-based phacotrabeculectomy over a 4-year period (2002-2005) at 1 eye surgery center (Vanak Eye Surgery Center, Tehran, Iran) by a single surgeon were reviewed, and postoperative CEC indices were measured. Preoperative CEC indices, performed for a then-ongoing trial, were compared with postoperative measurements of the last follow-ups. The main outcome measure was endothelial cell count. RESULTS: The median follow-up time was 12 months (range 9-24 months). There was no difference between the operations in improving visual acuity, lowering intraocular pressure, and decreasing the number of antiglaucoma medications required. However, 2-site surgery was associated with significantly more expansion in the CEC area (P < 0.001). On multivariate analysis, longer follow-up, 2-site surgery, and grade 4 cataract density were independently associated with more CEC loss, and longer follow-up, 2-site surgery, and steroid-induced glaucoma were associated with CEC area expansion. Postoperative complications were not markedly different between the 2 groups. CONCLUSIONS: In both groups, the longer the follow-up time was, the higher the CEC loss and the CEC area expansion were. One-site surgery seems to cause less CEC damage than the 2-site operation during the median follow-up time of 1 year.