Clear Cornea Research Articles

Vent Incisions to Facilitate Peripheral Unfolding of the DMEK Graft.

To present the results of 15 cases in which a modified technique of Descemet membrane endothelial keratoplasty (DMEK) with vent incisions was used to assist unfolding of tight peripheral inward folds. This is a retrospective case series of 15 consecutive eyes that underwent a modified vent incision technique for DMEK. Six oblique, small-size (1 mm) vent incisions parallel to the limbus and 3.5 mm from the center were performed after descemetorhexis. The graft was opened with standard no-touch techniques and was partially attached to the stroma with air injection. Then, in cases with remaining tight inward folds despite gentle corneal tapping, jets of balanced salt solution were pulsed through the vent incisions directed at the peripheral folds to achieve complete unfolding. Descemet membrane endothelial keratoplasty was performed in 2 phakic eyes (14%) and 13 pseudophakic eyes (86%). Six cases (40%) required fluid injection through the vent incisions: 3 corresponded to grafts from younger donors (54, 41, and 29 years old), and 3 had a 9.0-mm-sized graft. Complete graft unfolding was successfully achieved in 14 cases (93%), and in 1 case (7%), peripheral folds remained because of spontaneous bleeding in the anterior chamber. A clear cornea was achieved in all cases, and there were no postoperative complications associated with the vent incisions. This technique provides a different DMEK no-touch approach that could be used in challenging cases of graft unfolding such as young donors and/or large-sized grafts. It may also avoid excessive unfolding times and direct manipulation that are related to higher endothelial cell loss.

Descemet's membrane endothelial keratoplasty for treatment of patients with corneal endothelial decompensation

Objective: To evaluate the clinical outcomes of Descemet's membrane endothelial keratoplasty (DMEK) for treatment of patients with corneal endothelial decompensation in China. Methods: Interventional case series. Ten patients (10 eyes) with the diagnosis of corneal endothelial decompensation received DMEK during July 2016 and September 2016 in Zhongshan Ophthalmic Center. Descemet's membrane of the donor tissue was carefully stripped from the underlying stroma manually and cut with a 7.75- or 8.0-mm-diameter donor punch. After stained with 0.06% typan blue, the donor disc loaded on an inserter was gently inserted into the anterior chamber of the recipient. When the rolled graft was unfolded, air was carefully injected into the anterior chamber underneath the graft, so that the graft attached to the stroma of the recipient. All patients were followed up for 3-6 months. The best spectacle corrected visual acuity, the status of donor disc, corneal thickness and corneal endothelial cell density were documented and analyzed. Results: At 1 day after surgery, 1 donor disc presented a rolled edge, and repeated DMEK surgery was performed for this patient. The remaining 9 donor discs presented in place well. At 1 month after surgery, 7 donor discs were found to well attach to the back surface of the recipient stroma with normal corneal posterior surface using anterior segment optical coherence tomography. The average corneal thickness reduced to (620±67) μm from preoperative (680±78.3) μm (t=2.677, P=0.025). At 3 months after surgery, 6 patients achieved clear corneas with best spectacle corrected visual acuity ranging from 0.4 to 0.8. The endothelial cell density was 1 342.3±436.5 (872 to 1 933) cells/mm(2) in the patients with clear corneas. The average corneal thickness reduced to (612±70) μm (t=2.971, P=0.016). Conclusions: DMEK could improve visual acuity for corneal endothelial decompensation, but there were more technical difficulties in Chinese eyes. (Chin J Ophthalmol, 2017, 53: 534-539).

ANTERIOR IRIS ENCLAVATION OF A BLACK INTRAOCULAR LENS FOR LEUKOCORIA

A 32-year-old black woman was evaluated due to the cosmetic appearance of her blind left eye, with exotropia and leukocoria, which were interfering with her professional, social and personal life. The eye showed a clear cornea, quiet anterior chamber, normal iris and a white pupillary reflex due to white cataract and fibrotic retinal detachment. The Artisan® pupil occluder was enclavated retropupillary, keeping the cataract intact. After incision suture, strabismus was corrected. Despite the uneventful immediate post-operative course, two weeks after surgery the patient presented with posterior dislocation of the pupil occluder by release of one of the haptics, which induced cataract subluxation. Intracapsular cataract extraction was performed and the pupil occluder was repositioned anterior to the iris. At one year follow-up the eye remains quiet. The exotropia was corrected and the pupil occluder is well centered with an excellent cosmetic appearance. The patient is extremely satisfied with the result.

Assessment of Corneal Densitometry in Rheumatoid Arthritis Patients.

Objectives:To evaluate corneal densitometry and anterior segment parameters of rheumatoid arthritis (RA) patients and compare these results with those of age-matched healthy control subjects.Materials and Methods:Anterior segment parameters and corneal densitometry of patients with RA and healthy control subjects were assessed by Scheimpflug corneal topography. For densitometry analysis, the 12-mm diameter area of the cornea was subdivided into four concentric radial zones and anterior, central, and posterior layers based on corneal depth. Right eyes of subjects were used for statistical analysis.Results:Twenty-three consecutive patients with RA and 22 healthy control subjects were included in the study. There was no significant difference with regard to age (p=0.487) or gender (p=0.514). When anterior segment parameters of both groups were compared, no significant difference was found (p>0.05). Total corneal densitometry values were statistically higher in the RA group (p=0.030). In addition, when subdivisions of the cornea were evaluated, higher densitometry values were found in the RA group in 0-2 and 2-6 mm radial zones both in the anterior and total depth (p=0.001, p=0.003 for the 0-2 mm zone and p=0.002, p=0.009 for the 2-6 mm zone). Corneal densitometry measurement was not correlated with central corneal thickness or simulated keratometry value in RA patients or healthy control subjects.Conclusion:The corneal densitometry values were higher in RA patients when compared to healthy control subjects, even if they had clinically clear corneas. Corneal densitometry as an objective measure of corneal clarity warrants further studies in order to ascertain its clinical relevance in RA patients.

SUTURELESS CLEAR CORNEAL ULTRASONIC FRAGMENTATION FOR RETAINED LENS FRAGMENTS

To describe the safety and efficacy of removing posteriorly dislocated lens fragments with the use of intravitreal ultrasonic fragmentation through a limbal, clear cornea self-sealing incision. Patients presenting with posteriorly luxated nuclei were enrolled in this prospective case series. Preoperative examination included evaluation of the corneal endothelium by means of specular microscopy. A 3-port 25+ pars plana vitrectomy was initially performed. Following vitrectomy, sclerotomies were sealed using scleral plugs and a limbal/clear corneal incision was performed for the insertion of the fragmatome probe. The incision was slightly larger (1 mm) than the diameter of the fragmatome probe (20 gauge = 0.81 mm) to avoid wound overheating. At the end of the procedure, an appropriate intraocular lens either sulcus-fixated or angle-supported was implanted. Primary outcome measures were mean postoperative best-corrected visual acuity, intraoperative or postoperative complications, and intraoperative challenging features. In all eyes, fragmentation was completed successfully with a mean total ultrasound time of 113.4 seconds. Nucleus density was ≥3 in all cases (mean ± SD = 3.8 ± 0.4). Intraoperative challenges included viewing difficulties because of corneal distortion, fragment turbulence, and leakage through the limbal incision potentially compromising fundus visualization. There was statistically nonsignificant reduction in endothelial cell density ranging between 1932 ± 187 cells per square millimeter preoperatively to 1789 ± 213 cells per square millimeter at the first month postoperatively (P = 0.79). Clear corneal, sutureless ultrasonic fragmentation seems to be a novel, safe, and efficient method for the removal of hard posteriorly dislocated lens fragments, sparing the need for a 20-gauge scleral port.

Clinical results of non-Descemet stripping endothelial keratoplasty.

To investigate the impact of non-Descemet stripping endothelial keratoplasty (non-DSEK) on graft rejection rate, and its overall procedural effectiveness in patients. Non-DSEK was performed on 65 eyes of 64 patients, and the procedural outcomes, including rejection episodes, failure and dislocation of the grafts, best corrected visual acuity (BCVA), endothelial cell density (ECD), and other complications, were analyzed retrospectively. Of the 65 eyes, 63 recovered from bullous keratopathy with a clear cornea. The mean follow-up time was 26.4mo (range, 6-84mo). The mean BCVA improved from 1.70 logMAR preoperatively to 0.54 logMAR at 3mo, 0.46 logMAR at 6mo, and 0.37 logMAR at 1y after surgery. The postoperative donor ECD of the 25 patients who successfully underwent specular microscopic examination was 1918±534 cells/mm2 (range, 637 to 3056 cells/mm2), and the mean endothelial cell loss was 41.9% at 24mo postoperatively. One eye developed secondary glaucoma and required regrafting via penetrating keratoplasty (PKP). Another eye had postoperative graft failure due to rejection at 26mo. Postoperative graft dislocation occurred in eight eyes. All of the eight dislocated grafts were reattached using air reinjection. Immunological graft rejection of the donor graft rarely occurs in non-DSEK. Therefore, non-DSEK is a safe, concise, and effective alternative to restore corneal decompensation when the Descemet membrane is disease-free.

Subclinical Herpes Simplex Virus Type 1 Infections Provide Site-Specific Resistance to an Unrelated Pathogen.

HSV-1 infections of the cornea range in severity from minor transient discomfort to the blinding disease herpes stromal keratitis, yet most patients experience a single episode of epithelial keratitis followed by re-establishment of a clear cornea. We asked whether a single transient episode of HSV-1 epithelial keratitis causes long-term changes in the corneal microenvironment that influence immune responses to subsequent corneal infection or trauma. We showed that C57BL/6 mouse corneas infected with HSV-1 KOS, which induces transient herpes epithelial keratitis without herpes stromal keratitis sequelae, possessed a significant leukocytic infiltrate composed primarily of CD4+ T cells and macrophages along with elevated chemokines and cytokines that persisted without loss of corneal clarity (subclinical inflammation). Chemokine and cytokine expression was CD4+ T cell dependent, in that their production was significantly reduced by systemic CD4+ T cell depletion starting before infection, although short-term (3-d) local CD4+ T cell depletion postinfection did not influence chemokine levels in cornea. Corneas with subclinical inflammation developed significantly greater trauma-induced inflammation when they were recipients of syngeneic corneal transplants but also exhibited significantly increased resistance to infections by unrelated pathogens, such as pseudorabies virus. The resistance to pseudorabies virus was CD4+ T cell dependent, because it was eliminated by local CD4+ T cell depletion from the cornea. We conclude that transient HSV-1 corneal infections cause long-term alterations of the corneal microenvironment that provide CD4-dependent innate resistance to subsequent infections by antigenically unrelated pathogens.

Corneal profile in primary congenital glaucoma.

To investigate biomechanical and ultrastructural corneal parameters and ocular biometrics in the affected eyes of patients with unilateral primary congenital glaucoma (PCG) as compared to unaffected fellow eyes and age-matched healthy controls. A total of 12 patients with treated unilateral PCG and 10 normal subjects were evaluated. LENSTAR was performed to determine biometric parameters; the ocular response analyser was employed to determine biomechanical properties and slit-scanning confocal microscopy was used for evaluation of corneal ultrastucture. Axial length was significantly higher and mean keratometry in affected eyes was significantly flatter in affected eyes as compared to fellow eyes and normal controls (p<0.05), and a negative correlation was present between axial length and mean keratometry (p<0.05). Mean aqueous depth and anterior chamber depth were increased in affected eyes as compared to fellow eyes and normal controls (p<0.05). There was no significant difference in central corneal thickness (CCT) among affected eyes, fellow eyes and normal controls. Corneal hysteresis (CH) was significantly reduced in affected eyes (p<0.05) and corneal resistance factor (CRF) was also reduced in the affected eyes as compared to fellow eyes and normal controls, although not statistically significant. Mean endothelial cell density was reduced in the affected eyes compared to fellow eyes and normal controls (p<0.05). Corneal biometrics, biomechanical parameters and ultrastructural features are altered in eyes affected with PCG despite clinically normal and clear corneas. These findings should be considered in the preoperative assessment of intraocular or corneal surgery in these patients.

Endothelial keratoplasty for Fuchs dystrophy

We report the case of a 69-year-old female with Fuchs endothelial dystrophy and posterior chamber in-the-bag intraocular lens, whom we treated with DMEK surgical technique. We encountered difficulties both during obtaining the endothelium from the young donor and during the intraocular unrolling and its application on the stroma. We evaluated both preoperative and postoperative the following parameters: visual acuity, slit lamp, and optical coherence tomography appearance of the cornea, corneal thickness, intraocular pressure, endothelial cell density. In all postoperative assessments, the endothelium was attached to the host's stroma, with small peripheral, inferior folding area. Short-term results were favorable with a clear cornea and significant improvement in visual acuity obtained in the first 3 months of postoperative follow-up. Abbreviation: BCVA = best-corrected visual acuity, RE = right eye, LE = left eye, OCT = optical coherence tomography, DMEK = Descemet membrane endothelial keratoplasty.

Postoperative posterior capsular striae and the posterior capsular opacification in patients implanted with two types of intraocular lens material.

Aim:To evaluate the incidence of postoperative posterior capsular striae (PCS) and its influence on posterior capsular opacification (PCO) in patients implanted with two types of lens material.Setting:Tertiary eye care center in central rural India.Study Design:A prospective, observational, nonrandomized study.Materials and Methods:The study included 1247 patients having age-related cataract scheduled for removal by phacoemulsification technique and implantation of hydrophilic or hydrophobic intraocular lens (IOL). Demographic profile, nuclear grading, axial length, and IOL power were noted. Details of PCS were noted on the 1st postoperative day in patients with clear cornea. Postoperative follow-up was ensured to study the status of PCS and development of PCO.Results:The overall incidence of PCS was 19.8% (247 out of 1247 eyes). Out of 1247 patients, 641 patients (51.4%) had hydrophilic IOL implantation and 201 eyes had PCS (31.4%) and 606 patients (48.6%) had hydrophobic IOL implantation and 46 eyes had PCS (7.6%), P = 0.04. Three and more striae were seen in 119 eyes (119/641, 18.6%) in hydrophilic group and 4 eyes (4/606, 0.66%) in hydrophobic group. Sixty-two eyes (62/201, 30.9%) in hydrophilic group with multiple PCS were reported with persistent striae after 6 months of surgery. Two eyes in hydrophobic group had persistent striae even after 3 years of follow-up. Evaluation of PCO score of the hydrophilic group was 0.6 whereas of the hydrophobic group was 0.1 (P = 0.04). Ten patients of the hydrophilic group only required neodymium-doped yttrium aluminum garnet (ND: YAG) laser capsulotomy.Conclusion:The incidence of PCS was higher in hydrophilic than hydrophobic IOLs. Multiple PCS persisting in patients beyond 6 months after operation should be followed up for early development of PCO, particularly in patients implanted with hydrophilic IOL.

Patient satisfaction after femtosecond-assisted intracorneal ring segment implantation in the treatment of keratoconus

Purpose The aim of this article is to evaluate patient satisfaction after femtosecond-assisted intracorneal ring segment (ICRS) implantation in the treatment of keratoconus.Patients and methods The study was carried out in two private eye centers and Department of Ophthalmology at Alexandria University. This study is a retrospective type. The study included 30 keratoconus patients with moderate to severe keratoconus and clear central cornea. All patients underwent KeraRings ICRS implantation. All patients answered a specially designed questionnaire to evaluate their visual function and satisfaction within a period of 6 months to 1 year postoperatively. The correlations between questionnaire scores and the clinical parameters were studied.Results The clarity of vision in general was good for 50% of the cases, acceptable for 26.7%, and bad for 16.7%. Regarding night vision, 40% of the patients complained of bad night vision; while for 46.7% of the patients it was acceptable. Additionally, the analysis revealed that regarding ‘reading’ 73.4% of patients were satisfied. Sixty percent of the patients were satisfied with their far vision, postoperatively. Ninety-three percent and 90% of the patients complained of glare and haloes, respectively; 12 patients complained of fluctuation of vision. Significant correlations were those of SEQ (spherical equivalent of manifest refraction) and Kmax at the sixth month with general satisfaction with P value less than 0.001 and 0.013, respectively. Conclusively 70% of the patients were satisfied after ICRS implantation.Conclusion Most patients (70%) are generally satisfied after ICRS implantation for the treatment of keratoconus. However, night vision disturbance, glare and haloes are the main complaints for a large number of them (about 90%).

Minimally Invasive Surgery for the Removal of Posterior Intraocular Foreign Bodies.

This is a prospective clinical assay that included six patients who were diagnosed with penetrating corneal injury, traumatic cataract, and posterior segment intraocular foreign body (IOFB). Following anterior segment repair and extraction of traumatic cataract by clear cornea phacoemulsification, a standard 25-gauge transconjunctival pars plana vitrectomy was performed to find and release the IOFB. With active suction using a 25-gauge silicone tipped cannula, the foreign body was retrieved and safely placed in the anterior chamber. After stabilization of the anterior chamber with viscoelastic injection, IOFB extraction through the main phaco incision was easily performed, followed by placement of an intraocular lens. Of the six patients, 66.6% showed a significant improvement of visual acuity. No complications associated directly with the surgical procedure occurred. Our surgical technique is a safe alternative for handling and removing a posterior IOFB. There was no need for a scleral incision.

Http://jmsronline.com/archive-article/management-of-hyperglycemia-in-diabetics-with-cardiovascular-disease

Purpose: To present a case of systemic sclerosis with asymmetrical skin involvement, decreased tear production not responding to topical cyclosporine therapy and corneal edema in one eye. Methods: An 84 years old female diagnosed with scleroderma two years ago presented with history of decreased vision in the left eye of 10 days duration. Results: She had generalised tight skin which was more on the left side. The skin of the face including the eyelids was tight. Her best corrected visual acuity was 20/30, N6 in the right eye and in the left eye, it was 20/200. The Schirmer’s test without anaesthesia revealed a value of 3 mm in the right eye and 1 mm in the left eye. Anterior segment evaluation showed clear cornea with no guttata in the right eye. In the left eye, there was stromal oedema involving inferior half of the cornea with superficial blood vessels inferiorly. Both the corneas showed central superficial punctuate keratopathy. Anterior segment optical coherence tomography showed normal cornea in the right eye, whereas in the left eye there was hyper-reflectivity at the level of Descemet’s membrane suggestive of increased fibrosis and the corneal thickness was more. Conclusions: Systemic sclerosis can present with asymmetrical skin involvement, decreased tear production not responding to topical cyclosporine therapy and corneal edema in one eye. Further studies are warranted to develop treatment strategies of managing corneal edema in systemic sclerosis. Keywords: systemic sclerosis (SSc); scleroderma; secondary Sjogren’s syndrome; corneal oedema; anterior segment optical coherence tomography

Femtosecond Laser–Assisted Descemetorhexis

To explore the feasibility of femtosecond laser-assisted descemetorhexis (DR) to facilitate Descemet membrane endothelial keratoplasty (DMEK) surgery. Six pseudophakic patients suffering from Fuchs' endothelial dystrophy underwent femtosecond laser-assisted DMEK surgery. DR was performed using the LenSx femtosecond laser, followed by manual removal of the Descemet membrane. Optical coherence tomography images were used to measure DR parameters. Patients were followed up for 1 month to examine best corrected visual acuity, endothelial cell loss, flap detachment, and structure of the anterior chamber of the eye. The diameter of the DR approximated the intended diameter closely [mean error of 34 μm (0.45%) and 54 μm (0.67%) in the x- and y-diameter, respectively] and did not require manual correction. The median visual acuity increased from 0.4 logMAR (range 0.6-0.4 logMAR) preoperative to 0.2 logMAR (range 0-0.4 logMAR) postoperative. The median endothelial cell loss was 22% (range 7%-34%). No clinically significant flap detachments were noted. All patients had clear corneas after surgery, and no side effects or damage to structures of the anterior chamber were noted. Femtosecond laser-assisted DR is a safe and precise method for facilitating DMEK surgery.

Rupture of Descemet's membrane associated with forceps delivery

PurposeIn modern medicine forceps‐induced birth trauma to the eye is a rare clinical event. Forceps injury to the cornea occurs during complicated forceps delivery. The break in Descemet's membrane is the most common complication.MethodsInterventional case report showing the rupture of Descemet's membrane due to a complicated forceps delivery.ResultsA 2 days‐old boy was referred for severe and diffuse corneal edema. Medical history was significant for forceps delivery. On examination, he was found to have a rupture of the Descemet's membrane. Conservative treatment and application of hypersomolar solution was decided. Corneal edema was resolved in three months. Actually the cornea remained clear but persists a residual corneal astigmatism of 6D.ConclusionsThe application of the forceps can cause accidental rupture of the cornea at the level of the Descemet's membrane. The edema resolves spontaneously within a few weeks or months eventually leaving the visible edges of the break and a clear cornea. Rupture of Descemet's membrane is not presented as an Ophtalmologic urgency but it′s crucial to follow these patients because failure to intervene leads to amblyopia or ‘lazy eye’.

Ab Interno Trabeculectomy With the Trabectome as a Valuable Therapeutic Option for Failed Filtering Blebs.

Uncontrolled intraocular pressure (IOP) after glaucoma filtration surgery is a challenging problem in the management of glaucoma patients. The Trabectome is a device for selective electroablation of the trabecular meshwork through a clear cornea incision without affecting the conjunctiva. Minimally invasive glaucoma surgery using the Trabectome is safe and effective as primary glaucoma surgery. Here we investigate the results of ab interno trabeculectomy with the Trabectome for IOP control in patients with a failed filtering bleb. A total of 60 eyes of 60 consecutive patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PXG) were enrolled in this single center observational study. Trabectome surgery was performed alone or in combination with phacoemulsification by 2 experienced surgeons. IOP readings and number of IOP lowering medication as primary outcome parameters were taken by an independent examiner. Intraoperative and postoperative medication were recorded systematically. Mean IOP before surgery was 24.5±3.5 mm Hg and decreased to 15.7±3.4 (-36%) after mean follow-up of 415 days. The number of necessary IOP lowering medication dropped from 2.1±1.3 to 1.8±1.2 (14% reduction from baseline). A total of 25% (n=15) of cases reported here needed additional surgery after 517 days (range: 6 to 1563 d). No major complications were observed. After mean follow-up, we found a qualified success rate for PXG of 87% and 50% for POAG as revealed by the Kaplan-Meier analysis according to the definitions for success in advanced glaucoma cases according to the World Glaucoma Association (40% reduction from baseline IOP and maximum IOP of 15 mm Hg). Trabectome surgery for uncontrolled IOP after trabeculectomy is safe and effective especially in PXG patients. Given the demanding subgroup of patients studied here, it is not surprising that success rates are lower compared with previous studies investigating the Trabectome for primary glaucoma surgery. The number of necessary IOP lowering medication drops at first, but seems to reach preoperative values after 20 months of follow-up. Trabectome surgery should be considered as a valuable escape procedure for patients with failed filtering blebs and uncontrolled IOP.

Characterizing Contact Lens-Related Corneal Infiltrates: A Pilot Study.

Purpose:To document the time course and resolution of contact lens–related corneal infiltrative events (CIEs) comparing slit-lamp images with anterior segment ocular coherence tomography (AS-OCT) images.Methods:Six silicone hydrogel (SiHy) soft contact lens (SCL) wearers presenting with newly diagnosed symptomatic CIEs were monitored with slit-lamp images, detailed drawings, and AS-OCT until the resolution of the CIE. A final follow-up visit was completed 4 weeks after CIE resolution to determine whether scar formation was present. Positive controls were 2 SiHy SCL wearers with established (inactive) corneal scars, and negative controls were 2 SiHy SCL wearers with clear corneas. High- and low-contrast logMAR visual acuities were measured, and subjective symptom questionnaires were completed at all visits.Results:Clinical signs, vision, and symptoms improved in tandem with the resolution of the CIEs as measured by imaging methods. Calibrated measures of infiltrate width from a slit-lamp biomicroscope appear to be similar to calibrated images from AS-OCT.Conclusions:Although further studies are needed to develop standardized procedures, AS-OCT can be a useful tool to characterize the development, progression, and resolution of corneal infiltrates as an objective measure of resolution and scar formation.

Connection of histological corneal endothelial cell count with endothelial cell density before penetrating keratoplasty.

Corneal endothelial cell density and the integrity of the monolayer are essential for maintenance of a clear cornea. In 1992, Williams et al. introduced a method to estimate the endothelial cell density in histopathologic examination. It would enable an evaluation of the corneal host endothelium, even if preoperative measurement was not possible. The goal of this study is to evaluate the accuracy of the Williams equation in corneal buttons obtained from penetrating keratoplasties. High power field (HPF) photographs and histological endothelial cell counts were made from the corneal endothelial cells of each corneal histopathological cross-section. We then compared the calculated endothelial cell density using the Williams equation with the preoperative measured endothelial cell density. A bivariate regression analysis of the histological HPF cell counts and the preoperative endothelial cell density count was also performed. The equation of Williams et al. overestimates the endothelial density in all of our patients. Linear regression showed a strong relation between the central histological HPF count and the preoperative endothelial cell density. The regression formula for the endothelial cell density is 59.66 + (272.447 × HPF count); p < 0.001, R 2 = 0.901. This study confirms the relation between the corneal endothelial cell density, measured with specular microscopy, and the histopathological endothelial cell count in a HPF. However, the equation of Williams et al. provides an overestimation of the endothelial cell density. To proper utilize the histopathological endothelial cell count, a calibration of the equation coefficients in the local setting is necessary to prevent systematic errors.

Standard manual capsulorhexis / Ultrasound phacoemulsification compared to femtosecond laser-assisted capsulorhexis and lens fragmentation in clear cornea small incision cataract surgery.

BackgroundFemtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures. We decided to perform a comparative study to standard manual incision phacoemulsification surgery.MethodsThis is a single-center, single-intervention, and prospective comparative data evaluation of 133 consecutive cases subjected to cataract surgery. Group-A (Phaco), manual capsulorhexis & ultrasound phacoemulsification (n = 66); Group-B femtosecond-laser assisted capsulorhexis and lens fragmentation (n = 67), employing the LenSx laser (Alcon Surgical, Ft. Worth, TX). All cases were evaluated for refraction, visual acuity, keratometry, tomography, pachymetry, endothelial cell counts, intraocular pressure, and type of intraocular lens (IOL) implanted. The groups were matched for age, gender, pre-operative vision metrics, and cataract grade, and were followed up to 1 year.ResultsIn group-A post-operative uncorrected distance visual acuity (UDVA) was 20/20 or better in 61.5 % and 20/25 or better in 78.5 % of the eyes. The femtosecond laser group-B had improved outcomes (p = 0.075 and p = 0.042, respectively): post-operative UDVA was 20/20 or better in 62.7 % of the eyes and 20/25 or better in 85.1 %.Linear regression scatterplots of achieved versus attempted spherical equivalent had excellent regression coefficients (r2 = 0.983 in group-A and 0.979 in group-B). There were 75.2 % cases in group-A and 80.6 % in group-B (p = 0.8732) within ±0.50 D of targeted refractive equivalent. Slight trend of under-correction was noted in group-A. Average residual manifest cylinder in the toric subgroup-A was -0.50 D (95 % Limit-of-Agreement (LoA) = -0.78 D), and in toric subgroup-B -0.45 D (LoA = -0.45 D).ConclusionsMean spherical equivalent refraction and visual acuity are comparable with laser cataract surgery compared with manual capsulorhexis & ultrasound phacoemulsification. Improved astigmatism correction may be among the benefits of femtosecond laser–assisted cataract surgery. Transient corneal edema may be a first day transient disadvantage in femtosecond laser–assisted cataract surgery.

Long-Term Follow-Up of Amniotic Membrane Graft for the Treatment of Symblepharon in a Patient With Recessive Dystrophic Epidermolysis Bullosa

To report a case of symblepharon due to epidermolysis bullosa (EB), surgical treatment, and follow-up to 14 years. A 17-year-old white female with recessive dystrophic EB presented with decreased vision due to extensive symblepharon OU. There was opacification and neovascularization of the cornea OU with limited motility. The symblepharon was surgically lysed, anterior lamellar keratectomy performed, and amniotic membrane graft transplanted to the cornea and palpebral conjunctiva, first in the OS and subsequently in the OD. Visual acuity improved from counting fingers to 20/40 in the OS and from 20/200 to 20/70 in the OD at 2 months and 6 weeks postoperatively, respectively, with minimal symblepharon, mild corneal scarring, neovascularization, and haze of OU. She recovered full ductions, but noted diplopia and had a 35 prism diopter exotropia. Symblepharon resolved after 6 months, and alignment improved to 4 prism diopter exophoria. At 14 years follow-up, visual acuity was 20/20 in the OD and 20/30 in the OS, with clear cornea, maintained on fluorometholone 0.1% one drop OU at bedtime. Surgical symblepharolysis, superficial lamellar keratectomy, and amniotic membrane graft transplantation were effective for our patient with recessive dystrophic EB. Her postoperative exotropia resolved over time with monitoring and convergence exercises.