Corneal biomechanics in normal Saudi individuals.

PURPOSE: The aim of this study was to determine and relate corneal biomechanical metrics with demographic, tomographic and refractive data in healthy Saudi people. DESIGN: Prospective, cross-sectional, observational study. PARTICIPANTS: The study included 215 normal Saudi adult individuals. METHODS: Corneal hysteresis (CH) and corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated intraocular pressure (IOPcc) were measured by ocular response analyzer. The central keratometry (CK), central corneal thickness (CCT), and anterior chamber depth (ACD) were measured using Pentacam system. The spherical equivalent of refraction (SER) was obtained by an Auto-refractometer. RESULTS: The mean CH was 11.16 ± 2.11, CRF was 11.07 ± 2.31 and IOP was 15.12 ± 3.5. Mean CK, ACD, CH and CRF were distinct among gender with the significant P values of 0.05, 0.006, 0.020, and 0.047 respectively. CRF was negatively correlated with ACD (r = -0.146, P = 0.032). A positive correlation was found between CRF and SER (r = 0.176, P = 0.010), CCT (r = 0.447, p = 0.000) and CH (r = 0.878 and p = 0.000). CH was negatively correlated with IOPcc (-0.433, p = 0.000). A positive correlation was found between CH and ACD (r = -0.14, p = 0.044), SER (r = 0.617, p = 0.014), CCT (r = 0.412, p = 0.000) and IOPg (r = 0.183, p = 0.007). CONCLUSION: This study demonstrated a distinct difference among gender values of corneal hysteresis and corneal resistance factor being higher in female Saudi subjects. CH and CRF values were higher in Saudi subjects than values in other populations. This may suggest the presence of ethnic differences in ocular parameters and support the importance of establishing population norms for corneal biomechanical parameters.

Boston keratoprosthesis - Clinical outcomes with wider geographic use and expanding indications - A systematic review.

Over 2 decades of research, several design modifications, and improvements in post-operative management have made Boston keratoprosthesis (B-KPro) a viable option for patients with corneal blindness for whom traditional keratoplasty procedure has a very low probability of success. In this systematic review, we examined the indications, visual outcomes, complications and retention rate of the literature published in the past 10 years (2005-2014). While most of the studies report smaller datasets (typically <50 eyes), some of the recent multicenter studies have reported large datasets (up to 300 eyes). Most of the literature is published from the US; however, last few years have witnessed some papers reporting the successful use of B-Kpro from developing countries or arid climatic conditions (such as the Kingdom of Saudi Arabia). Due to differences in the causes of corneal blindness in different geographic regions, newer indications for B-Kpro are emerging (e.g. trachoma). Additionally, improving clinical outcomes and increasing surgeon confidence have also expanded indications to include cases of unilateral visual impairment and paediatric age. We observed that there is growing body of evidence of successful clinical use of B-KPro; however, financial challenges, lack of trained surgeons, shortage of donor corneas must be overcome to improve accessibility of B-KPro.

Urrets-Zavalia syndrome after implantable Collamer lens placement.

We describe the case of a healthy 28-year-old woman who underwent implantation of a posterior chamber, phakic, toric, implantable Collamer lens (ICL) in both eyes for correction of bilateral high myopia with astigmatism. On the first postoperative day the patient developed increased intraocular pressure (IOP) and a fixed, mid-dilated pupil in her left eye. The elevated IOP was corrected within 3 days by medical treatment. However, the pupil remained mid-dilated and nonreactive to both light and accommodative effort during 2 months of follow-up; there was no reaction to pilocarpine (0.125% or 4%) eyedrops. The patient was diagnosed with Urrets-Zavalia syndrome (UZS), which has been reported in association with ICL implantation only once previously.

Retention of the Boston keratoprosthesis type 1: multicenter study results.

OBJECTIVE: To report the retention rate of the Boston keratoprosthesis type 1 and to identify risk factors for keratoprosthesis loss. DESIGN: Cohort study. PARTICIPANTS: A total of 300 eyes of 300 patients who underwent implantation of the Boston keratoprosthesis type I device between January 2003 and July 2008 by 19 surgeons at 18 medical centers. METHODS: Forms reporting preoperative, intraoperative, and postoperative parameters were prospectively collected and subsequently analyzed at a central data collection site. MAIN OUTCOME MEASURES: Keratoprosthesis retention. RESULTS: A total cumulative number of 422 life-years of device implantation are included in this analysis. The average duration of follow-up was 17.1 ± 14.8 months, with a range of 1 week to >6.1 years. Ninety-three percent of the 300 Boston keratoprosthesis implants were retained at their last follow-up, corresponding to a retention time of 396 patient-years or 1.42 years/keratoprosthesis. The probability of retention after 1 year and 2 years was 94% and 89%, respectively. During the study period, 21 (7%) eyes failed to retain the device; the reasons for keratoprosthesis loss include sterile keratolysis (9), fungal infections (8), dense retroprosthetic membranes (3), and bacterial endophthalmitis (1). Multivariate analysis demonstrated 3 independent risk factors for keratoprosthesis loss: autoimmune cause (hazard ratio [HR], 11.94; 95% confidence interval [CI], 3.31-43.11), ocular surface exposure requiring a concomitant tarsorrhaphy (HR, 3.43; 95% CI, 1.05-11.22), and number of prior failed penetrating keratoplasties (HR, 1.64; 95% CI, 1.18-2.28). CONCLUSIONS: The Boston keratoprosthesis type 1 seems to be a viable option for eyes that are not candidates for penetrating keratoplasty (PK). Ocular surface disease due to an autoimmune cause demonstrated the lowest retention rate. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Initial experience with Descemet stripping automated endothelial keratoplasty in Saudi Arabia.

PURPOSE: To analyze the visual results of Descemet stripping automated endothelial keratoplasty (DSAEK) in the first consecutive 10 cases. MATERIALS AND METHODS: Retrospective, non-randomized, non-comparative interventional case series. Ten eyes of 10 patients with endothelial dysfunctions of different etiology, scheduled for DSEAK, were included in this study. Indications, operative problems, and postoperative complications were noted. Best-corrected visual acuity, refractive and keratometric astigmatism, and central corneal thickness were analyzed for each patient after a minimum follow-up of 10 months. RESULTS: In a median follow-up of 12 months (range 10-16 months), visual outcomes were satisfactory. Preoperative diagnosis included five eyes of psuedophakic bullous keratopathy and two eyes of repeated failed corneal grafts and one bullous keratopathy secondary to anterior chamber phakic IOL implantation. Two eyes with Fuchs dystrophy and cataract had combined DSAEK and phacoemulsification and IOL implantation. One patient had known glaucomatous optic nerve precluding vision better than 20/150. Of the remaining nine patients, four eyes had BSCVA of 20/40 or better by postoperative 6 months (3 by 3 months). The average pachymetry was 646.9 µm. One patient had total graft dislocation and one needed trabeculectomy. None of the patients developed graft rejection or graft failure. None of patients needed to convert to penetrating keratoplasty. CONCLUSION: DSAEK is safe and effective procedure in patients with endothelial dysfunctions with encouraging surgical and visual outcomes.

Risk factors for the development of retroprosthetic membranes with Boston keratoprosthesis type 1: multicenter study results.

OBJECTIVE: The purpose of this study was to identify possible risk factors for retroprosthetic membrane (RPM) development in a large, multicenter cohort of patients receiving a Boston type 1 keratoprosthesis. DESIGN: Cohort study. PARTICIPANTS: The final analysis included 265 eyes of 265 patients who underwent implantation of a Boston keratoprosthesis type I device between January 2003 and July 2008 by 1 of 19 surgeons at 18 medical centers. METHODS: Forms reporting preoperative, intraoperative, and postoperative parameters were prospectively collected and subsequently analyzed at a central data collection site. MAIN OUTCOME MEASURES: The primary outcome was the presence or absence of an RPM during the follow-up period. RESULTS: The average age of patients was 63.3±19.1 years, 48.5% of the patients were female, and 52.5% of procedures were performed on the right eye. The mean follow-up time was 17.8±14.9 months. The majority (85.4%; n = 222) had undergone an average of 2.2±1.2 (range, 1-8) penetrating keratoplasties before keratoprosthesis implantation, and 38 eyes (14.6%) received a primary keratoprosthesis. The overall RPM formation rate was 31.7% (n = 84). The most significant risk factor for RPM development was infectious keratitis (as a surgical indication for keratoprosthesis surgery itself), resulting in a rate of RPM formation of 70.6%. As an independent risk factor, the hazard ratio (HR) of RPM development in these eyes was 3.20 (95% confidence interval, 1.66-6.17). Aniridia was also an independent risk factor for RPM development (HR, 3.13; 95% confidence interval, 1.10-8.89). CONCLUSIONS: Formation of RPM is a common complication of keratoprosthesis surgery, occurring in approximately one-third of cases. Eyes at the highest risk of RPM development are those receiving corneal replacement for infectious keratitis and aniridia.

Short-term visual outcomes of Boston keratoprosthesis type I in saudi arabia.

PURPOSE: To evaluate the visual outcomes, complications and retention of threadless type I Boston keratoprosthesis (KPro) in Saudi Arabia. MATERIALS AND METHODS: Retrospective analysis of four eyes of four patients (one female and three males; age range: 48 to 72 years) who underwent Boston type I threadless KPro implantation between January and December 2009. RESULTS: In the median follow-up of 11 months (range 6 to 14 months), visual outcomes were satisfactory. Preoperative diagnosis included two patients of post-trachoma dense vascularized corneal scarring, one patient of corneal alkali burn and one patient of repeated failed corneal grafts. All patients demonstrated significant improvement in vision; with pre-operative visual acuity of hand movements (HM), counting fingers and HM improved to best corrected visual acuity (BCVA) of 20/200, 20/60, 20/50 and 20/30 on their last follow-up visits respectively. None of the patients developed glaucoma as a result of the procedure. No retro-prosthetic membrane developed till the last follow-up visit. One of the four patients had a corneal melt (due to severe dryness associated with trachoma) 6 months after the KPro implantation and underwent a successful KPro revision. Despite the relatively poor prognosis expected in alkali burn eye, the patient attained the maximum BCVA (20/30) of the four eye series on the last follow-up visit at six months. CONCLUSION: In consistent with the earlier reports from other parts of the world, all the 4 eyes had a significant increase in vision after Boston type I KPro implantation. However, patients require close lifelong follow-up to manage any complications.

Healed corneal ulcer with keloid formation.

We are reporting a 34-year-old Arabic white female patient who presented with a white mass covering her left cornea following multiple ocular surgeries and healed corneal ulcer. The lesion obscured further view of the iris, pupil and lens. The patient underwent penetrating keratoplasty and the histopathologic study of the left corneal button showed epithelial hyperplasia, absent Bowman's layer and subepithelial fibrovascular proliferation. The histopathologic appearance was suggestive of a corneal keloid which was supported by further ultrastructural study. The corneal graft remained clear 6 months after surgery and the patient was satisfied with the visual outcome. Penetrating keratoplasty may be an effective surgical option for corneal keloids in young adult patients.

Spontaneous corneal perforation in ocular rosacea.

Rosacea is a dermatologic condition that affects the midfacial region. Ocular rosacea is most frequently diagnosed when cutaneous signs and symptoms are also present. Ocular manifestations are essentially confined to the eyelids and ocular surface. Ocular involvement ranges from minor irritation, dryness, and blurry vision to potentially severe ocular surface disruption including corneal ulcers, vascularization and rarely perforation. We present a 49-year-old Saudi Arabian female with the diagnosis of rosacea who presented with a peripheral corneal performation. The perforation was successfully managed by surgical repair, oral doxycycline and topical steroid. The final best corrected visual acuity was 20/30 after treatment. Early referral to an ophthalmologist and careful long-term follow-up are recommended.

Conjunctival nevi: Clinical and histopathologic features in a Saudi population.

BACKGROUND AND OBJECTIVE: Conjunctival nevi are benign lesions with wide variation in clinical and histopathological features. The differentiation between benign nevi and other pigmented lesions is essential. The aim of our study was to identify the distribution of the histopathologic types of conjunctival nevi among the Saudi population and to provide the basic knowledge needed for proper clinical diagnosis. PATIENTS AND METHODS: This retrospective study of surgically excised benign conjunctival nevi was conducted at a tertiary care eye hospital from 1995 to 2006. Clinical data was collected from medical records and the histopathologic features reviewed by a single pathologist. RESULTS: A total 105 conjunctival nevi were included from 104 consecutive patients (mean age, 26 years, 54 males and 50 females). The anatomical location was the bulbar conjunctiva in 83%, juxtalimbal in 12%, caruncle in 4% and palpebral in 1%. The lesion was removed for cosmetic reasons in 38% while 8% of the lesions were removed to rule out malignancy. The compound nevus was the commonest (72%) in all age groups, followed by subepithelial nevus (24%) and finally junctional nevus (3%). CONCLUSIONS: The distribution of the histopathologic types of this tumor in our population matches the pattern in other areas of the world with the compound nevus being the commonest lesion. However, fewer lesions among our patients are removed to rule out malignancy.

Repositioning free laser in situ keratomileusis flaps.

We describe a protocol for adequate repositioning of free laser in situ keratomileusis (LASIK) corneal flaps created by a Moria M2 microkeratome even in the absence of fiduciary marks. In an enucleated porcine globe, a free flap was created by initially placing a longitudinal incision at the proposed hinge site followed by activating the forward pass of the automated microkeratome. A protocol was devised based on placement of a positioning dot on the free flap before the flap is retrieved from the microkeratome head. Preplaced surgical landmarks were used as a guide to determine the correct alignment of the free flap. Adequate orientation of the free flap to the stromal bed was achieved in 9 porcine eyes using the positioning dot method. The technique is applicable to the Moria M2 microkeratome only and must be validated for other types of keratomes.

Topical bevacizumab in the treatment of corneal neovascularization: results of a prospective, open-label, noncomparative study.

OBJECTIVE: To study the safety and efficacy of topical bevacizumab in the treatment of corneal neovascularization (NV). DESIGN: In a prospective, open-label, noncomparative study, 10 eyes from 10 patients with stable corneal NV were treated with topical bevacizumab, 1.0%, for 3 weeks and followed up for up to 24 weeks. MAIN OUTCOME MEASURES: The primary safety variables were the occurrence of ocular and systemic adverse events throughout the course of the study. The primary efficacy variables were neovascular area, the area of the corneal vessels themselves; vessel caliber, the mean diameter of the corneal vessels; and invasion area, the fraction of the total corneal area covered by the vessels. RESULTS: From baseline visit to the last follow-up visit, mean reductions were 47.1% (standard deviation [SD], 36.7%) for neovascular area, 54.1% (SD, 28.1%) for vessel caliber, and 12.2% (SD, 42.0%) for invasion area. The decreases in neovascular area and vessel caliber were statistically significant (P= .001 and P< .001, respectively). However, changes in invasion area did not achieve statistical significance (P= .19). Visual acuity and central corneal thickness showed no significant changes. Topical bevacizumab was well tolerated with no adverse events. CONCLUSIONS: Short-term topical bevacizumab therapy reduces the severity of corneal NV without local or systemic adverse effects. APPLICATION TO CLINICAL PRACTICE: Topical bevacizumab provides an alternative therapy in the treatment of stable corneal NV. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00559936.