Journal of Current Ophthalmology
Volume:22 Issue: 4, 2010 Dec

Glaucoma following penetrating keratoplasty (PK) continues to be a serious problem that may ultimately become sight threatening. Knowledge of the risk factors for development of glaucoma following PK, such as preexisting glaucoma, pseudophakia, aphakia, and previous PK, can limit the occurrence and improve the outcome of the keratoplasty. The management of postkeratoplasty (Post-PK) glaucoma remains controversial with a wide range of treatment modalities available, including newer classes of drugs, laser therapy, filtering surgery with mitomycin C, and implantation of glaucoma drainage devices (GDDs), as well as various cycloablative treatment modalities, including cyclocryotherapy and cyclophotocoagulation (CPC) with noncontact and contact neodymium: yttrium-aluminum-garnet (Nd:YAG) laser, a semiconductor diode, and endoscopic cyclophotocoagulation (ECP). A literature search was conducted on the Medline database using the search terms glaucoma, PK, trabeculectomy, GDDs, cyclocryotherapy, Nd:YAG CPC, diode laser CPC, and ECP for the 35-year period between 1975 and 2010. Several articles that were not found by Medline search were cited in the references of other articles. Articles were included because of their subject relevance or were excluded so as to avoid redundancy. Abstracts written in English of non-English-language articles were also reviewed.

To compare the outcomes of coaxial microincision phacoemulsification with that of conventional coaxial phacoemulsification SETTING: Department of Ophthalmology, Farabi and Noor Eye Hospitals, Tehran, Iran In a prospective study, 74 eyes of 74 patients with cataract were randomly selected to have cataract extraction using 1 of 2 techniques: coaxial microincision phacoemulsification through a 2.2 mm incision (37 eyes) or conventional coaxial phacoemulsification through a 2.8 mm incision (37 eyes) and foldable intraocular lens (IOL) (SA60; Alcon) implantation. Intraoperative parameters were effective phacoemulsification time (EPT), surgical time, and total volume of balanced salt solution (BSS) used. Assessed ocular biometrics included corneal topography, to evaluate surgically induced astigmatism (SIA), as well as corneal thickness and endothelial cell count (ECC). Using vectorial analysis the amount of SIA was 0.04±0.34 diopter (D) at 126.7 degrees in the 2.8 mm group and 0.07±0.49 D at 11.8 degrees in the 2.2 mm group, at one month postoperatively. At 3 months, the SIA was 0.06±0.41 D at 134.7 degrees and 0.10±0.62 at 161.4 degrees in the 2.8 mm and 2.2 mm groups, respectively. Although coaxial microincision cataract surgery (MICS) was a safe and effective technique there were no clinical or statistically significant differences between 2 techniques in minimizing the effect of incision size on SIA.

To evaluate the biomechanical changes of cornea after intracorneal ring segment (ICRS) implantation in keratoconic eyes In this study, 1 or 2 ICRS were inserted in 17 keratoconic eyes. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), refraction, and keratometry were evaluated preoperatively and 1 and 3 months after surgery. Corneal hysteresis (CH) and corneal resistance factor (CRF) were also measured preoperatively and postoperatively with ocular response analyzer (ORA). ICRS was inserted in 17 keratoconic eyes (12 patients). Mean UCVA significantly increased from 0.72±0.37 logMAR to 0.54±0.27 logMAR (P=0.027) and 0.46±0.30 logMAR (P=0.01) 1 and 3 months after surgery, respectively. Mean BSCVA increased from 0.41±0.29 logMAR to 0.32± 0.26 logMAR at the end of the 1st month and 0.32±0.27 logMAR at the end of 3rd month postoperatively. These changes were not significant. Spherical equivalent (SE) significantly decreased from -5.64±3.21 Diopter (D) to -3.36±2.74 D (P=0.009) 1 month and -3.51±2.04 D (P=0.002) at the 3 months after surgery. Mean keratometry also significantly decreased from 49.82±4.33 D to 48.10±3.64 D (P=0.010) and 47.40±3.47 D (P=0.003) at 1- and 3- month follow-ups, respectively. Mean CH was 7.48±1.65 mmHg and mean CRF was 5.98±2.06 mmHg, preoperatively. At 1-month follow-up, their values were 7.13±1.56 mmHg and 5.74±1.60 mmHg, respectively. At 3-month follow-up, their values were 7.20±1.23 mmHg and 5.80±1.72 mmHg, respectively. The CH and CRF changes at 1- and 3-month follow-ups were not significant. After ICRS insertion in keratoconic eyes, no significant changes were observed in mean values measured with the ORA at 1- and 3-month follow-ups.

To compare the outcome of surgery and postoperative complications between using manually dissected cornea in Descemet’s stripping with endothelial keratoplasty (DSEK) and using eye bank automated precut cornea in Descemet’s stripping with automated endothelial keratoplasty (DSAEK) Forty eyes with indication of endothelial keratoplasty (EK) were included in this randomized prospective clinical trial. The eyes were randomly divided into two groups. Donor cornea in one group was dissected with curved blade by the surgeon, while precut cornea from eye bank was used in other group. All surgeries were performed in one center by three surgeons, authors of the article. Patients were followed for 3 months. Baseline parameters and demographic features were not significantly different between the two groups. The most common indication of EK in both groups was pseudophakic bullous keratopathy (PBK) (60%). Endothelial cell loss in DSEK and DSAEK were 51.59% and 50.70%, respectively after 3 months follow-up (P=0.947). Best spectacle-corrected visual acuity (BSCVA) and intraocular pressure (IOP) after surgery and postoperative complications were not significantly different in both groups. Prevalence and intensity of interface opacity was significantly lower in DSAEK group after surgery. BSCVA equal or more than 20/100 was detected in 85% and 75% individuals in DSAEK and DSEK groups, respectively. In conclusion, three months postoperative outcomes of EK were similar in the two groups of precut DSAEK and manually dissected DSEK. Smooth and uniform layer in precut DSAEK leads to lower interface opacity in patients.

To evaluate the correlation of central corneal thickness (CCT) with refractive error and keratometry in a group of patients eligible for laser keratorefractive surgery, which may serve as a bias in studies on intraocular pressure (IOP) measurement In a cross sectional observational study, the right eyes of 340 patients who underwent laser keratorefractive surgery during the year 2006 were included. The CCT was measured with ultrasound pachymetry. The refractive error, including sphere, cylinder, and spherical equivalent (SE), based on cycloplegic refraction. Keratometry (K) readings were derived from topography printouts. The correlation between refractive indices and CCT was investigated in all cases and also in refractive subgroups. The mean±SD age of the patients was 28.7±7.7 years, ranging from 18 to 55 years. Seventy percent of the patients were female. The mean cycloplegic SE and CCT were -3.2±2.3 diopters (D) and 549.5±33.6 µm, respectively. A borderline negative correlation between age and CCT was observed (r=-0.1, P=0.05). None of the other parameters including gender, amount of refractive error (Sphere, cylinder and axis), and K-readings showed any significant correlation with CCT (P>0.05) in the whole group or different subgroups. In this refractive surgery population, refractive indices did not show any significant correlation with CCT. This suggests that the correlation between CCT and IOP which has been found by other investigations in similar populations is in accordance to our findings.

To investigate the validity of Pentacam derived parameters like corneal volume distribution and percentage increase in volume in differentiation of mild to moderate keratoconus from normal corneas Forty eyes with mild to moderate keratoconus and 200 normal eyes were studied by Pentacam. Corneal volume was calculated within diameters from 1.0 to 7.0 mm with 0.5 mm steps centered on the thinnest point to create the corneal volume distribution. The percentage increase in volume was calculated for each position of the corneal volume distribution from their first value. Statistical analysis was done using the Mann-Whitney test to compare mean levels of two groups and the Wilcoxon test for two consecutive measurements. Statistically significant differences were observed between the keratoconic and normal corneas (P<0.01) in all positions of corneal volume distribution and in the percentage increase in volume. The differences between the curves of the two groups were more significant in 3 mm diameter and further. There are significant difference between corneal volume distribution and percentage increase in volume in keratoconic and normal corneas and could serve as valid indices to diagnose mild and moderate forms of keratoconus.

The aim of this study is to measure the endogenous cortisol levels in the patients with central serous chorioretinopathy (CSCR) and also, evaluate the short-term effect of oral ketoconazole in the treatment of both acute and chronic CSCR. In this prospective interventional case series 12 patients with acute CSCR and 7 patients with chronic CSCR (Including one patient with bilateral chronic disease) were treated with oral ketoconazole 200 mg two times per day. Measurement of best corrected visual acuity (BCVA), macular thickness [Using optical coherence tomography (OCT)], and 24-hour urinary cortisol levels were done before and after one month of treatment. Abnormal elevated levels of 24-hour urinary cortisol were identified in 50% of cases at presentation and it reduced after treatment (P=0.03). In acute CSCR patients, pretreatment mean logMAR BCVA was 0.3±0.2 and improved to 0.1±0.1 after treatment (P=0.005). Also central macular thickness was significantly reduced after treatment (P=0.001). Complete or partial improvement in central macular thickness and BCVA were happened in four from eight eyes with chronic CSCR. Oral ketoconazole (400 mg/day) may be a noninvasive and safe therapeutic option for patients with acute CSCR and may alter the clinical course of some patients with chronic disease.

The aim of this study was to evaluate the effect of adjuvant treatments on contrast sensitivity in patients with clinically significant macular edema (CSME) treated with macular photocoagulation (MPC). Forty eight eyes from 30 patients with non-proliferative diabetic retinopathy (NPDR) and CSME were included in a prospective randomized clinical trial between August 2008 and October 2009. They randomly assigned in sham injection, intravitreal bevacizumab (IVB) injection (1.25 mg/0.05 cc) and intravitreal triamcinolone (IVT) injection (2 mg/0.05 cc) groups. MPC was done within 1 month for them. Detailed fundus examination, ocular coherence tomography, and determination of best corrected visual acuity (BCVA) and contrast sensitivity which were repeated after 3 and 6 months are reported. A total of 48 eyes from 30 patients were enrolled. CSME resolved in 32 (66.6%) of 48 eyes 3 months after MPC. Despite no statistical significant difference in visual acuity (VA) among groups, contrast sensitivity in IVB group was significantly higher than sham group in 4.8 cycles per degree (cpd) (P=0.03). Also contrast sensitivity in IVT group was significantly higher than sham group in 4.8 cpd (P=0.03) and 12 cpd (P=0.03). Six months after MPC, 37 eyes (77.08%) had resolved CSME. There was no significant difference in VA among groups but contrast sensitivity at 4.8 cpd in IVT group was significantly higher than sham group (P=0.005). There was no significant difference between the other groups. Three months after MPC, IVT combined with MPC and IVB combined with MPC had better effect on contrast sensitivity comparing MPC alone. Six months after MPC, IVT combined with MPC was associated with greater beneficial effects on contrast sensitivity than MPC alone.

To offer a semi-automatic algorithm to determine the area of angiographic hyperfluorescence The proposed algorithm included wavelet filter, histogram equalization and modified Otsu thresholding. Hyperfluorescent area of 30 angiographic images obtained from patients with leaking choroidal neovascularization (CNV) and diabetic retinopathy were evaluated and the results were compared with those obtained by an expert ophthalmologist. The best wavelet filter was determined. Quantitative assessment of the hyperfluorescent area showed a mean error of 0.12±0.59 square millimeters. There was no significant difference between algorithm-measured and ophthalmologist-measured area. The proposed algorithm may be used to accurately measure area of hyperfluorescence.

To report a case of retained silicone tube Case report : We report a case of 48-year-old Iranian lady who referred to the department of otolaryngology with 18 years history of epiphora and intermittent mucopurulant discharge from the left lacrimal canaliculi. She had external dacryocystorhinostomy (DCR) with silicon stenting for epiphora 18 years ago but epiphora had continued after surgery. Preoperative irrigation test revealed partial obstruction and in diagnostic nasal endoscopy the previous rhinostomy site was patent. She was operated with revision endoscopic DCR approach and an impacted 15 millimeters piece of silicon tube was removed from lacrimal sac. This case should alert surgeons to the possibility of foreign bodies as a cause of persistent epiphora after DCR surgery.

To report an association of ligneous conjunctivitis (LC) and congenital hydrocephalus Case report : The patient was a 3.5-year-old boy with a history of long standing conjunctivitis with copious ocular discharge and photophobia, waxing and waning for some time. He also had suffered from occlusive congenital hydrocephalus that required placement of a ventriculoperitoneal shunt. Conjunctivitis did not respond to topical medications and recurred after several excisions. Finally an intralesional methylprednisolone injection was performed. Significant resolution of the lesions was observed after one week and after one year, LC was relatively controlled and there was no need for more excisions. In patients with recurrent recalcitrant pseudomembrane, this treatment shortens the treatment period, evokes rapid visual rehabilitation and obviates the need for the future excisions. Also, this report reemphasizes the association of LC and congenital hydrocephalus, which maybe ignored.

read the recent publication on contrast sensitivity, color vision and visual acuity with a great interest.1 Heravian et al. concluded that “The findings also suggest that the appropriate combination of existing tests may be a useful method of improving screening accuracy in diabetic patients1”. I agree that the combination might be a good way to increase the sensitivity of screening. However, it is questionable whether this proposed combination a really good alternative choice. The use of many investigations might increase sensitivity but reduce specificity. This means increased false diagnosis. Although good agreement can be observed the problem in the case with disagreement might be expected. Finally, “Does the slightly increased sensitivity is cost effective for funding?” is the question for discussion.