Comparative posterior corneal profile of keratoconus hydrops versus Haab's striae in congenital glaucoma

Keratoconus eyes develop corneal decompensation more often compared to eyes with primary congenital glaucoma (PCG) following Descemet's membrane (DM) tear. This study was conducted to compare the posterior corneal morphology in areas with DM breaks with regards to DM and pre-Descemet's layer (PDL) between the two. In this cross-sectional comparative study, anterior segment optical coherence tomography (AS-OCT) scans of the posterior cornea of advanced keratoconus eyes with hydrops ( n = 12), PCG eyes with Haab's striae ( n = 15), and healthy control eyes ( n = 14) were compared for DM-PDL morphology. These were further corroborated by the histopathology of corneal buttons from keratoconus ( n = 14) and PCG ( n = 13) cases obtained following penetrating keratoplasty and compared with controls (enucleated retinoblastoma globes, n = 6) on light microscopy and collagen IV immunostaining. AS-OCT showed a thicker median DM/PDL complex in PCG (80 µm) versus keratoconus eyes (36 µm, P = 0.01; Kruskal-Wallis test). The median height and length of detached DM-PDL were significantly more in keratoconus versus PCG (145 μm, 1766.1 ± 1320.6 μm vs. 26.5 μm, 453.3 ± 303.2 μm, respectively, P = 0.012; Kruskal-Wallis test). Type-1 DM/PDL detachment (seen as a characteristic taut chord) in keratoconus (90%) was the most common morphological pattern versus intracameral twin protuberance (92%) following DM breaks in PCG. Histopathology confirmed thicker DM in PCG (median: 63.4 μm) versus keratoconus eyes (median: 33.2 µm) or controls (27.1 μm) ( P = 0.001; Kruskal-Wallis test). Greater height/length of DM/PDL detachment compounded by poor healing response (lower DM/PDL thickness) probably causes more frequent corneal decompensation in keratoconus eyes when compared to PCG eyes following DM tears.

Expression and Impact of Fibronectin, Tenascin-C, Osteopontin, and Type XIV Collagen in Fuchs Endothelial Corneal Dystrophy

Purpose

Fuchs endothelial corneal dystrophy (FECD) is characterized by Descemet's membrane (DM) abnormalities, namely an increased thickness and a progressive appearance of guttae and fibrillar membranes. The goal of this study was to identify abnormal extracellular matrix (ECM) proteins expressed in FECD DMs and to evaluate their impact on cell adhesion and migration.

Methods

Gene expression profiles from in vitro (GSE112039) and ex vivo (GSE74123) healthy and FECD corneal endothelial cells were analyzed to identify deregulated matrisome genes. Healthy and end-stage FECD DMs were fixed and analyzed for guttae size and height. Immunostaining of fibronectin, tenascin-C, osteopontin, and type XIV collagen was performed on ex vivo specimens, as well as on tissue-engineered corneal endothelium reconstructed using healthy and FECD cells. An analysis of ECM protein expression according to guttae and fibrillar membrane was performed using immunofluorescent staining and phase contrast microscopy. Finally, cell adhesion was evaluated on fibronectin, tenascin-C, and osteopontin, and cell migration was studied on fibronectin and tenascin-C.

Results

SPP1 (osteopontin), FN1 (fibronectin), and TNC (tenascin-C) genes were upregulated in FECD ex vivo cells, and SSP1 was upregulated in both in vitro and ex vivo FECD conditions. Osteopontin, fibronectin, tenascin-C, and type XIV collagen were expressed in FECD specimens, with differences in their location. Corneal endothelial cell adhesion was not significantly affected by fibronectin or tenascin-C but was decreased by osteopontin. The combination of fibronectin and tenascin-C significantly increased cell migration.

Conclusions

This study highlights new abnormal ECM components in FECD, suggests a certain chronology in their deposition, and demonstrates their impact on cell behavior.

Corneal Guttae After Descemet Membrane Endothelial Keratoplasty

PURPOSE

The aim of this study was to report on the occurrence of corneal guttae after Descemet membrane endothelial keratoplasty (DMEK).

METHODS

In this retrospective case series, 13 eyes of 13 patients who underwent DMEK at 2 tertiary referral centers between 2007 and 2021 (average available follow-up 73 ± 52 months, range 18-174 months) and showed corneal guttae during postoperative examinations were included. Eye bank images were retrospectively reviewed.

RESULTS

Occurrence of guttae was observed by specular microscopy in 13 eyes. In 11 cases, presence of guttae was confirmed by confocal microscopy and in 1 case by histology. Five eyes showed an increase in guttae density during the postoperative course. Surgery indications were Fuchs endothelial corneal dystrophy (n = 11), pseudophakic bullous keratopathy (n = 1), and DMEK graft failure after allograft rejection (n = 1); the latter eye had shown no signs of guttae after primary DMEK. Two eyes with guttae required a repeat DMEK due to graft failure. At the last available follow-up, all 11 remaining eyes had clear corneas and 10 eyes had a best-corrected visual acuity of ≥0.9 (decimal). During donor cornea processing in the eye bank, no guttae were observed on the donor tissue.

CONCLUSIONS

Corneal guttae can occur after DMEK including in eyes operated for indications other than Fuchs endothelial corneal dystrophy and most likely guttae were present on the donor graft but were not detectable by routine slit-lamp and light microscopy evaluation in the eye bank. Postoperative guttae density varies among patients and especially small isolated guttae do not seem to affect clinical outcomes.

Factors associated with endothelial cell density loss post Descemet membrane endothelial keratoplasty for bullous keratopathy in Asia

PURPOSE

To investigate the factors associated with endothelial survival after Descemet's membrane endothelial keratoplasty (DMEK) in eyes of Asian patients with bullous keratopathy (BK).

METHODS

In this retrospective, consecutive interventional case series, 72 eyes of 72 patients who underwent DMEK were evaluated. Best corrected visual acuity (BCVA) and corneal endothelial cell density (ECD) were assessed at 12 months postoperatively. Multiple regression analysis was performed to assess parameters such as age, sex, axial length, preoperative visual acuity, re-bubbling, the ratio of graft to cornea area, iris damage scores, types of filling gases, air or SF6 volume in the anterior chamber (AC) on postoperative day 1, and ECD loss rates at 12 months postoperatively.

RESULTS

BCVA improved significantly at 12 months after DMEK (P < .001). The rate of ECD loss at 12 months after DMEK was 54.4 ± 16.1%. Multiple linear regression analysis showed that a larger ratio of graft to corneal area (P = 0.0061) and higher donor ECD (P = 0.042) were the primary factors for a lower ECD loss rate at 12 months after DMEK.

CONCLUSION

A relatively larger graft size compared to the host cornea and more donor ECD might help endothelial survival in patients with BK. Moreover, for such patients, the surgeon should attempt to use a relatively larger graft size when performing DMEK, particularly in Asian eyes.

The Corneal Basement Membranes and Stromal Fibrosis

Purpose

The purpose of this review was to provide detailed insights into the pathophysiology of myofibroblast-mediated fibrosis (scarring or late haze) after corneal injury, surgery, or infection.

Method

Literature review.

Results

The epithelium and epithelial basement membrane (EBM) and/or endothelium and Descemet's basement membrane (BM) are commonly disrupted after corneal injuries, surgeries, and infections. Regeneration of these critical regulatory structures relies on the coordinated production of BM components, including laminins, nidogens, perlecan, and collagen type IV by epithelial, endothelial, and keratocyte cells. Whether a cornea, or an area in the cornea, heals with transparency or fibrosis may be determined by whether there is injury to one or both corneal basement membranes (EBM and/or Descemet's BM) and delayed or defective regeneration or replacement of the BM. These opaque myofibroblasts, and the disordered extracellular matrix these cells produce, persist in the stroma until the EBM and/or Descemet's BM is regenerated or replaced.

Conclusions

Corneal stromal fibrosis (also termed "stromal scarring" or "late haze") occurs as a consequence of BM injury and defective regeneration in both the anterior (EBM) and posterior (Descemet's BM) cornea. The resolution of fibrosis and return of stromal transparency depends on reestablished BM structure and function. It is hypothesized that defective regeneration of the EBM or Descemet's BM allows key profibrotic growth factors, including transforming growth factor beta-1 (TGF-β1) and TGF-β2, to penetrate the stroma at sustained levels necessary to drive the development and maintenance of mature opacity-producing myofibroblasts from myofibroblast precursors cells, and studies suggest that perlecan and collagen type IV are the critical components in EBM and Descemet's BM that bind TGF-β1, TGF-β2, platelet-derived growth factor, and possibly other growth factors, and regulate their bioavailability and function during homeostasis and corneal wound healing.

Proteomic analysis of corneal endothelial cell-descemet membrane tissues reveals influence of insulin dependence and disease severity in type 2 diabetes mellitus

The objective of this study was to characterize the proteome of the corneal endothelial cell layer and its basement membrane (Descemet membrane) in humans with various severities of type II diabetes mellitus compared to controls, and identify differentially expressed proteins across a range of diabetic disease severities that may influence corneal endothelial cell health. Endothelium-Descemet membrane complex tissues were peeled from transplant suitable donor corneas. Protein fractions were isolated from each sample and subjected to multidimensional liquid chromatography and tandem mass spectrometry. Peptide spectra were matched to the human proteome, assigned gene ontology, and grouped into protein signaling pathways unique to each of the disease states. We identified an average of 12,472 unique proteins in each of the endothelium-Descemet membrane complex tissue samples. There were 2,409 differentially expressed protein isoforms that included previously known risk factors for type II diabetes mellitus related to metabolic processes, oxidative stress, and inflammation. Gene ontology analysis demonstrated that diabetes progression has many protein footprints related to metabolic processes, binding, and catalysis. The most represented pathways involved in diabetes progression included mitochondrial dysfunction, cell-cell junction structure, and protein synthesis regulation. This proteomic dataset identifies novel corneal endothelial cell and Descemet membrane protein expression in various stages of diabetic disease. These findings give insight into the mechanisms involved in diabetes progression relevant to the corneal endothelium and its basement membrane, prioritize new pathways for therapeutic targeting, and provide insight into potential biomarkers for determining the health of this tissue.

Late-onset descemet membrane detachment and corneal decompensation after laser peripheral iridotomy: A case report

RATIONALE

The incidence of cornea disorders after laser peripheral iridotomy (LPI) is extremely low. However, cornea Descemet membrane detachment (DMD) combined with corneal decompensation after LPI could still occur.

PATIENT CONCERNS

A 69-year-old Chinese woman presented with persistent widespread corneal edema and inferior bullous lesions in her right eye for half a year. She had undergone LPI in both eyes 10 years ago for a prophylactic treatment. The patient received a detailed examination of vivo corneal confocal microscopy and sept-source optical coherence tomography (SS-OCT).

DIAGNOSES

It was a late-onset DMD that has a positional relationship with LPI, combined with corneal decompensation.

INTERVENTION

Treatment was only supportive with artificial tears and soft contact lenses.

OUTCOMES

This patient declined to accept keratoplasty because of financial difficulties.

LESSONS

Laser peripheral iridotomy may cause spontaneous, late-onset DMD and corneal decompensation. Ophthalmologists should be aware of this potential complication and proceed carefully. A careful examination of cornea especially around the LPI before keratoplasty seems to be necessary to circumvent other complication.

Factors Associated With Early Graft Detachment in Primary Descemet Membrane Endothelial Keratoplasty

PURPOSE

To evaluate the risk factors for early graft detachment in Descemet membrane endothelial keratoplasty (DMEK).

DESIGN

Case-control study.

METHODS

Participants: A total of 173 donor corneas and 173 eyes of the patients following DMEK or DMEK in combination with phacoemulsification and intraocular lens implantation were included.

INTERVENTION

Pre-stripped DMEK grafts were transplanted using pull-through technique. At the end of surgery, the anterior chamber was filled with air, which was removed 3 hours later only if pupillary block was suspected. Rebubbling was performed in all cases with graft detachment, independently of its extension, as documented by means of anterior segment optical coherence tomography. The donor characteristics were collected from the eye bank database and matched with the recipient database.

MAIN OUTCOME MEASURES

Donor and recipient characteristics affecting graft detachment using univariate and multivariate analysis.

RESULTS

The combination of DMEK with cataract removal and IOL implantation (odds ratio [OR] = 5.31, 95% confidence interval [CI] 2.03-13.86, P < .002) and air fill of ≤75% of anterior chamber height at 2-3 hours postoperatively (OR = 2.66, 95% CI 1.12-6.34, P = .027) were found to be independent risk factors for postoperative graft detachment.

CONCLUSIONS

Cataract removal at the time of DMEK is a risk factor for early graft detachment and therefore sequential surgery may be preferred over combined surgery in an attempt at minimizing rebubbling. Air level in the anterior chamber should be monitored and maintained above 75% in the early hours following surgery.

Effect of vital dyes on human corneal endothelium and elasticity of Descemet's membrane

The purpose of this study was to evaluate the effects of vital dyes on human Descemet's membranes (DMs) and endothelia. DMs of 25 human cadaveric corneas with research consent were treated with dyes routinely used in Descemet membrane endothelial keratoplasty (DMEK), 0.05% Trypan blue (TB) or a combination of 0.15% Trypan blue, 0.025% Brilliant blue and 4% Polyethylene glycol (commercial name Membrane Blue Dual; MB). The effects of these two dyes on (i) endothelial cell viability, (ii) DM mechanical properties as assessed by atomic force microscopy, and iii) qualitative DM dye retention were tested for two varying exposure times (one or four minutes). No significant differences in cell toxicity were observed between treatments with TB and MB at the two different exposure times (P = 0.21). Further, both dyes led to a significant increase in DM stiffness: exposure to TB and MB for one minute increased the apparent elastic modulus of the DM by 11.2% (P = 8*10⁻³) and 17.7%, respectively (P = 4*10⁻⁶). A four-minute exposure led to an increase of 8.6% for TB (P = 0.004) and 13.6% for MB (P = 0.03). Finally, at 25 minutes, the dye retention of the DM was considerably better for MB compared to TB. Taken together, a one-minute exposure to MB was found to improve DM visibility compared to TB, with a significant increase in DM stiffness and without detrimental effects on endothelial cell viability. The use of MB could therefore improve (i) visibility of the DM scroll, and (ii) intraoperative unfolding, enhancing the probability of successful DMEK surgery.

The Effect of Eye Patching on Clear Corneal Incision Architecture in Phacoemulsification: A Randomized Controlled Trial

PURPOSE

To investigate the effects of postoperative eye patching on clear corneal incision architecture in phacoemulsification.

DESIGN

A single-center, randomized controlled trial.

METHODS

A total of 132 patients with uncomplicated phacoemulsification were randomly allocated to the intervention or control group. The intervention group received postoperative eye patching for approximately 18 hours, whereas the control group received eye shield. The clear corneal incision architecture was examined postoperatively at 2 hours, 1 day, and 7 days after surgery using optical coherence tomography.

RESULTS

Epithelial gaping was significantly reduced on postoperative day 1 in the intervention group (52.4%) compared with control (74.2%) (P = 0.01). No differences were found for other architectural defects. Descemet membrane detachment was associated with lower intraocular pressure on postoperative day 7 (P = 0.02). Presence of underlying diabetes mellitus did not seem to influence architectural defects.

CONCLUSIONS

Postoperative eye patching facilitated epithelial healing and reduced the occurrence of epithelial gaping on postoperative day 1. It may play a role in protecting and improving corneal wounds during the critical immediate postoperative period.

Graft detachment and rebubbling rate in Descemet membrane endothelial keratoplasty

Descemet membrane endothelial keratoplasty (DMEK) is a selective replacement of dysfunctional endothelium with healthy donor Descemet membrane and endothelium. Although the donor preparation and surgical methods still remain a challenge, DMEK is gaining popularity in terms of early rehabilitation and visual outcomes. New and improved donor preparation techniques like prestripped DMEK tissues are being taken up rapidly because of less manipulation that is required in the surgical theatre. Donor graft delivery in the recipient eye has also been improved because of new products like prestripped and preloaded membranes. As DMEK is at its budding stage, only early outcomes have been known so far. Early graft detachment, rebubbling rates, and primary failures are still being studied in DMEK. As there are different techniques that are currently used for preparation and injection of the graft, it becomes difficult to judge the results based on specific inclusion and exclusion criteria. Graft detachment and rebubbling rates have been a huge challenge both during the surgery and also while reporting postoperative data. We highlight the importance of defining graft detachment and rebubbling rates and their surgical relevance, which may also have an impact on graft preparation and insertion techniques.

Late onset Descemet's membrane detachment 20 years after penetrating keratoplasty

This paper reports a case of spontaneous Descemet's Membrane (DM ) detachment 20-years after penetrating keratoplasty (PK). The patient presented with acute onset blurred vision in the right eye associated with mild ocular discomfort. There was no prior history of trauma. The patient had undergone PK in the right eye 20 years back. Detailed ophthalmic examination showed best corrected visual acuity of hand movements close to face in the right eye and 20/80 in the left eye. The right eye showed diffuse graft edema but no congestion, epithelial defect, or loss of continuity of graft-host junction to suggest a traumatic etiology. Anterior segment optical coherence tomography showed DM break with a detachment in the right eye, which was treated with an intracameral C3F8 injection. DM break with detachment post-PK has been very sparsely reported in literature and is an important differential to remember when faced with an edematous graft, in addition to the diagnosis of graft rejection or failure.

[Descemetectomy : An alternative to transplantation?]

Due to rising demand worldwide it is becoming increasingly more difficult to satisfy the needs for human corneal transplants. At this point transplantation is the only possible cure for endothelial diseases, such as Fuchs endothelial dystrophy. In this article we present descemetectomy, a circumscribed removal of Descemet's membrane (DMx) without subsequent transplantation, as new possible treatment option on the basis of a clinical case.

Eye bank prepared versus surgeon cut endothelial graft tissue for Descemet membrane endothelial keratoplasty: An observational study

The purpose of this article is to examine outcomes of Descemet membrane endothelial keratoplasty (DMEK) performed with cornea bank (CB) prestripped tissue and surgeon stripped tissue (SST).This retrospective study examined subjects who underwent DMEK with CB or surgeon prepared tissue for Fuchs endothelial corneal dystrophy. Best-corrected visual acuity (BCVA), corneal thickness, endothelial cell count (ECC), and complications were examined before and throughout a 6-month postoperative period.Eleven CB and 22 SST subjects were included. Six months after surgery, BCVA was 20/20 or better in 36.4% of CB and 22.7% of SST subjects (P = .43). Median logMAR BCVA was 0.10 (0.00-0.20, 20/25) in group CB and 0.10 (0.10-0.30, 20/25) in group SST. Median preoperative corneal thickness was 614.0 μm (577.5-662.0 μm) and 658.0 μm (606.0-689.0 μm) in CB and SST subjects, respectively (P = .37). Six months after surgery, median corneal thickness was lower in the CB group (571.0 μm [478.0-592.0 μm]), than in the SST group (576.0 μm [531.0-607.0 μm], P = .02). At 6 months, median ECC was 1500.0 cell/mm (1321.5-2049.0 cell/mm, 41% decrease) in group CB and 1403.0 cell/mm (972.5-2010.7 cell/mm, 46% decrease) in group SST (P = .70). Rebubbling was required in 5 CB (45.5%) and 15 SST (68.2%) subjects (P = .39).Fuchs' dystrophy patients have good anatomic and functional DMEK results. Similar outcomes and complication rates occurred with eye bank and surgeon prepared donor tissue.

Endothelium-in versus endothelium-out for Descemet membrane endothelial keratoplasty graft preparation and implantation

PURPOSE

To evaluate the difference between endothelium-in and endothelium-out for Descemet membrane endothelial keratoplasty (DMEK) preparation and implantation using injection method.

METHODS

The study was a randomized, comparative, institutional, laboratory investigation. Eighteen human donor corneas were included. A total of 9.5 mm DMEK grafts were stripped and restored on the corneal base with a hinge and preserved in the deswelling medium. The grafts were detached from the hinge and either manually tri-folded with the endothelium on the inside, or allowed to spontaneously roll in phosphate-buffered saline (PBS) with endothelium outwards. The corneas were mounted on an artificial anterior chamber (AAC) and four incisions made using a 15° eye knife for the side ports and slit knife to create a 3.0 mm incision for delivery of the graft into the AAC. The grafts with endothelium-in (endo-in) were pulled into a cartridge, whereas those with endothelium-out (endo-out) were aspirated using a modified Jones tube. Both were delivered using an injection method. Central and peripheral endothelial cell density (pre- and post-delivery and after removal), time of preparation and unfolding were measured.

RESULTS

Endothelial cell loss postimplantation was 10.53% (±2.82) with endo-in (n = 9) compared to 7.56% (±14.74) with endo-out (n = 9) (p > 0.05). Preparation and unfolding time was 4.43 min (±3.43) and 0.96 min (±1.10) for endo-in compared to 1.68 min (±0.57) and 4.92 min (±4.21) for endo-out. A statistical significance between endo-in and endo-out for loading (p = 0.04) and unfolding (p = 0.023) time was observed.

CONCLUSIONS

Descemet membrane endothelial keratoplasty tissues can be tri-folded (endo-in) with no significantly less cell loss as compared to endo-out. Spontaneous unfolding of endo-in may reduce overall time and surgical manipulation.

Anterior Segment Optical Coherence Tomography Imaging of Haab Striae

The authors present a case series demonstrating the anterior segment optical coherence tomography (AS-OCT) findings of Haab striae in three patients with congenital glaucoma. The use of AS-OCT in the assessment of Haab striae in pediatric glaucoma is novel, previously undescribed, and possibly allows differentiation between acute and chronic corneal changes.

Perfluoropropane (C3F8) injection for Descemet's membrane detachment in cataract surgery

BACKGROUND

Descemet's membrane (DM) detachment is an important cause of surgery related corneal edema that may lead to corneal decompensations and marked reduction in visual acuity if not identified and treated promptly. We prescent a case of postoperative Descemet's membrane detachment that occurred after complicated manual small incisional cataract surgery. Descemetopexy in post-cataract surgery descemet's membrane detachment has not yet been reported in Nepal.

CASE

A 45 year old female underwent manual small incision cataract surgery of the right eye. Intraoperatively, there was descemet's membrane detachment so: anterior chamber tamponade with air was done. She was discharged with a visual acuity of 6/24. But on the eighth postoperative day, her visual acuity had decreased to 1/60 in right eye with corneal edema, detached descemet's membrane and descemet's folds. Hence was re-admitted for repositioning of descemet's membrane with C3F8 (14% gas mixed with air). The procedure successfully reattached the descemet's membrane. Corneal edema regressed and the gas bubble resolved after 15th day of the surgery. Patient's visual right acuity was 6/36 in right eye and the intraocular pressure was 12mmhg.

CONCLUSION

DM detachment should not be taken lightly because of the potential for grave visual outcome. One needs to examine carefully, as the signs of DM detachment can be subtle and may be masked by corneal edema. During the past few years, intracameral injection with perfluoropropane (C3F8) gas has also gained increasing acceptance as an efficient and effective treatment option for Descemet's membrane detachments.

Histopathologic and optical coherence tomography observation after descemet's stripping endothelial keratoplasty in rabbits

OBJECTIVES

To study the histopathologic and optical coherence tomography changes after Descemet's Stripping Endothelial Keratoplasty in rabbits.

MATERIALS AND METHODS

Descemet's Stripping Endothelial Keratoplasty was performed in 14 rabbit eyes and descemetorhexis was performed in 10 rabbits, as control. Histopathologic examination and anterior-segment optical coherence tomography were conducted in the Descemet's Stripping Endothelial Keratoplasty group at 1, 2, 4, and 8 weeks. For the control group, histopathologic examination was performed before surgery and at 1, 2, 4, and 8 weeks after surgery.

RESULTS

In the Descemet's Stripping Endothelial Keratoplasty group, corneas cleared completely within 2 weeks of surgery. Moreover, in most cases, the retained Descemet's membrane was present at the peripheral donor-host interface. The retrocorneal fibrocellular membrane also was seen in the peripheral Descemet's membrane stripped area without donor coverage. Anterior-segment optical coherence tomography revealed that the stroma deturgesed most rapidly between weeks 1 and 2.

CONCLUSIONS

Retained Descemet's membrane was not the cause for graft dislocation and the retrocorneal fibrocellular membrane may be a kind of protective reaction to denuded endothelium.

Phenotype and genotype analysis in patients with macular corneal dystrophy

AIM

The aim of this study was to analyse corneal morphological organisation and identify mutations in the carbohydrate sulfotransferase 6 gene (CHST6) in patients with macular corneal dystrophy originating in a Polish population.

METHODS

Macular corneal dystrophy was diagnosed in 24 patients based on the slit-lamp exam, confocal microscopy, 1310 nm time domain and 840 nm spectral domain optical coherence tomography. 10 corneal buttons obtained from penetrating keratoplasty were processed for light microscopy. Genetic analysis of the CHST6 gene was performed, followed by a study of the sequencing results.

RESULTS

Highly reflective, diffuse corneal deposits and a general increase in reflectivity were revealed with optical coherence tomography and confocal microscopy. The deposits extended from the Bowman layer to the Descemet membrane and correlated with the Alcian blue-positive granular-filamentous material into and around the stromal keratocytes confirmed by structural analysis of the corneal buttons. The genetic analysis of the blood samples identified the following mutations and single nucleotide polymorphisms: novel P64L (heterozygous), Y110C (homozygous), R162G and L200R, and M1L (heterozygous and homozygous).

CONCLUSIONS

Genetic mutation heterogeneity was revealed. No phenotype heterogeneity was revealed among patients with in vivo corneal morphology assessment or histological analysis.

[Urgent therapeutic penetrating autokeratoplasty for a purulent corneal ulcer in the only functional eye]

The article presents a case of severe purulent corneal ulcer in the only functional eye of a young patient with Frank-Kamenetsky glaucoma and high-degree myopia. Combination therapy was ineffective and the patient developed a descemetocele. Due to the absence of cadaver corneas and small size of the only available conserved Alloplant cornea, the contralateral cornea (of the blind eye, which was enucleated under general anesthesia) was used for urgent therapeutic penetrating autokeratoplasty. Postoperative period was complicated with ocular hypertension, which was surgically resolved. To overcome the critical situation around keratoplasty, with results from Russian regulation gaps, the authors suggest creating interregional eye banks in large cities that would provide sampling, conservation and storage control of donor material in accordance with the existing legislation.

[Descemet's stripping automated endothelial keratoplasty for endothelial failure after penetrating keratoplasty]

PURPOSE

To evaluate the outcome of Descemet's stripping automated endothelial keratoplasty (DSAEK) in eyes with endothelial failure after penetrating keratoplasty (PK).

SUBJECTS AND METHODS

DSAEK was performed on 13 eyes of 13 patients with failed PK. Their mean age was 73.2 years. Evaluation of visual acuity, subjective astigmatism, corneal endothelial cell density, and complications was performed.

RESULTS

In four eyes, PK was performed after previous surgery for hypometropia by Sato's anterior-posterior radial keratotomy. Mean followup time was 20.3 +/- 8.6 months. Mean logarithmic minimum angle of resolution (logMAR) visual acuity was 1.92 before DSAEK and 0.89 at final follow-up. Mean subjective astigmatism was 5.10 +/- 3.09D before surgery and 7.25 +/- 4.16 D at 6 months postoperatively. Mean corneal endothelial cell density at 6, 12, 24 months after DSAEK was 42.8%, 51.3%, 72.1%, respectively. Regarding postoperative complications, air was reinjected in four eyes, persistent epithelial defect and rejection occurred in one eye each, and PK was repeated in three eyes.

CONCLUSION

DSAEK rapidly improved visual acuity after failed PK, but some eyes required repeat PK. Eligibility criteria for DSAEK after failed PK should be established.

The 7-year cumulative incidence of cornea guttata and morphological changes in the corneal endothelium in the Reykjavik Eye Study

PURPOSE

To examine the corneal endothelium and establish the 7-year cumulative incidence of cornea guttata (CG).

METHODS

Population-based prospective cohort study with 573 participants (third wave of the Reykjavik Eye Study (RES) in 2008). Four hundred and thirty-seven subjects had either right or left eyes available for analysis after excluding confounding eye conditions. The baseline for eyes at risk for developing CG is the second wave of the RES in 2001. Participants underwent specular microscopy and a standardized eye examination.

RESULTS

The cumulative 7-year incidence of CG in either eye was estimated as a 95% confidence interval for the expected value for both genders combined (15-23%), for males (8-18%) and for females (19-29%). In right eye only, the 7-year cumulative incidence for both genders combined was estimated to be 6-11%. For genders combined and for males only, the data indicated no correlation between 7-year cumulated incidence and age at baseline. In women, however, the change of 7-year incidence for CG in at least one eye appeared to be correlated to age at baseline. Reduction of endothelial cell density for corneas with CG at baseline was found [CI (0.95)-132 ± 94].

CONCLUSION

The cumulative 7-year incidence of primary central CG for a middle-aged and older Caucasian population without history of potentially confounding eye disease has been established. Women tend to have higher incidence if onset occurs at middle age. If CG is present, the cell density and the cell size variation decrease within a 7-year period.

Suture pull-through insertion techniques for Descemet stripping automated endothelial keratoplasty in Chinese phakic eyes: outcomes and complications

Purpose

To investigate the outcomes and complications of suture pull-through insertion techniques for Descemet stripping automated endothelial keratoplasty (DSAEK) in Chinese phakic eyes.

Patients and Methods

Retrospective case series. Included in the study were all Chinese patients with phakic eyes who underwent DSAEK at Peking University Third Hospital from August 2008 to August 2011. All ocular diseases of the patients were recorded. Distance visual acuity (DVA), near visual acuity (NVA), intraocular pressure (IOP), anterior chamber depth (ACD), central corneal thickness (CCT), and corneal endothelial cell density (ECD) were compared prior to and 12 months after DSAEK. The DSAEK success rate, endothelial cell loss (ECL), complications, and prognosis were analyzed. All patients had at least 12 months of follow up.

Results

Twenty-one eyes of 16 patients were included (11 males and 5 females). Ages ranged from 2 to 47 years with an average age of 29.8 years. The average follow up was 15.4 months (ranging from 12 to 36 months). Diagnoses included 7 eyes (4 patients) with corneal endothelial dystrophy and 14 eyes (12 patients) with bullous keratopathy. Presurgical DVA and NVA (LogMAR) were 1.7±0.7 and 1.2±0.4; postsurgical DVA and NVA were 0.8±0.6 and 0.7±0.5; Z = −3.517, −2.764; P<0.001 and P = 0.006 respectively. Presurgical IOP was 15.8±3.7 mm Hg; postsurgical IOP was 15.2±2.6 mm Hg; Z = −0.505, P = 0.614. Presurgical ACD was 3.00±0.74 mm; postsurgical ACD was 2.72±0.59 mm; Z = −0.524, P = 0.600. Donor ECD was 2992±163 cells/mm², ECD was 1836±412 cells/mm² with a 12-month postsurgical ECL of 39%. Success rate was 86%. Surgery complications included pupillary block-induced hypertension in 5 eyes (24%), graft detachment in 3 eyes (14%), and graft dislocation in 1 eye (5%).

Conclusions

DSAEK on Chinese phakic eyes can significantly improve DVA and NVA by preserving the patient’s own crystalline lens. DSAEK is an optional surgery for patients who need to preserve accommodative function. More attention should be given to postsurgical pupillary block-induced hypertension.

Anatomic and visual outcomes of descemetopexy in post-cataract surgery descemet's membrane detachment

OBJECTIVE

To study the anatomic and visual outcomes of descemetopexy in Descemet's membrane detachment (DMD) after cataract surgery.

DESIGN

Retrospective case series.

PARTICIPANTS

Clinical notes of 60 patients who underwent DMD after cataract surgery between 2007 and 2011.

METHODS

Descemetopexy was performed with air or 14% isoexpansile perfluoropropane (C3F8).

MAIN OUTCOME MEASURES

Anatomical (reattachment rates) and functional results (best-corrected visual acuity) were studied. Secondary outcome measures were assessment of surgical complications and association of various factors with final visual outcome.

RESULTS

The mean age of the patients was 64.3 ± 8.3 years, and the male:female ratio was 21:39. At 1 month, the mean logarithm of the minimum angle of resolution (logMAR) interval visual acuity (IVA) improved from 1.27 ± 0.8 to 0.42 ± 0.49 (P < 0.001). Five patients (8.3%) obtained 20/20 vision, and 37 of 60 patients (61.6%) achieved IVA of ≥ 20/40. Ninety-five percent (57/60) of patients had successful reattachment of the Descemet's membrane (DM) after the intervention. Multiple linear regression analysis showed that patients with a cataract score of 5 (estimate = 0.38; P=0.014), with a cataract score of 4 with compromised visibility due to a corneal opacity (estimate = 0.45; P=0.039), and prolonged duration between cataract surgery and descemetopexy (estimate = 0.012; P=0.007) were associated with a significantly poorer final visual outcome. No association of final visual outcome was observed with age; sex; eye treated; cataract scores 2, 3, and 4; preoperative visual acuity; and involvement of the visual axis (P > 0.5). The eyes in which air was used for descemetopexy (estimate = -0.2; P=0.009) had statistically significantly better final visual outcomes. Three patients (5%) had treatment failures and required subsequent endothelial transplantation. Pupillary block was observed in the early postoperative period in 7 patients (11.66%) in whom C3F8 had been used and was not seen with air (P=0.02).

CONCLUSIONS

This study suggests that DMD after cataract surgery can be treated effectively and good visual outcomes can be expected if the patient is treated in time with anterior chamber injection of gas. Air has advantages of better efficacy than C3F8 without the risk of pupillary block and thus should be preferred.

[Posterior lamellar keratoplasty with DSEK technique and use of the Tan EndoGlide - short-term results]

PURPOSE

To present the differences in surgical technique of DSEK (Descemet's Stripping Endothelial Keratoplasty) with the use of Tan EndoGlide (Coronet, UK) and Busin Glide (Moria, FR). Short-term results will also be presented,

MATERIAL AND METHODS

DSEK was performed in 24 eyes, in 8 cases the surgery was combined with cataract phacoemulsification and lOL implantation. Surgery course and 6 months postoperative results of first 12 eyes performed with the use of Tan EndoGlide were compared with 12 consecutive eyes preformed with Busin Glide.

RESULTS

Tan EndoGlide provided much more stable anterior chamber, donor tissue unfolding process was better controlled but the incision was wider incision. Surgically induced mean refractory cylinder 6. months after the surgery was 1.56 - 1.15 Dsph in Tan EndoGlide group and 1.18 +/- 1.10 Dsph in Busin Glide group (P <0.05). The endothelial cell loss was 20.5% and 21.12% respectively (P>0.05). Mean CDVA was 0.65+/- 0.27 and 0.63 +/- 0.25, respectively (P>0,05). Statistically significant differences in intra- and post-operative complications between both groups were not found.

CONCLUSIONS

The Tan EndoGlide used during posterior lamellar keratoplasty with DSEK technique is a good alternative to currently used methods. It provides better stabilization of the anterior chamber, however its use is linked with higher postoperative astigmatism in comparison with Busin Glide. The visual outcomes and endothelial cell loss 6 months after the surgery were similar in both groups.

Hyperglycemia-induced abnormalities in rat and human corneas: the potential of second harmonic generation microscopy

Background

Second Harmonic Generation (SHG) microscopy recently appeared as an efficient optical imaging technique to probe unstained collagen-rich tissues like cornea. Moreover, corneal remodeling occurs in many diseases and precise characterization requires overcoming the limitations of conventional techniques. In this work, we focus on diabetes, which affects hundreds of million people worldwide and most often leads to diabetic retinopathy, with no early diagnostic tool. This study then aims to establish the potential of SHG microscopy for in situ detection and characterization of hyperglycemia-induced abnormalities in the Descemet’s membrane, in the posterior cornea.

Methodology/Principal Findings

We studied corneas from age-matched control and Goto-Kakizaki rats, a spontaneous model of type 2 diabetes, and corneas from human donors with type 2 diabetes and without any diabetes. SHG imaging was compared to confocal microscopy, to histology characterization using conventional staining and transmitted light microscopy and to transmission electron microscopy. SHG imaging revealed collagen deposits in the Descemet’s membrane of unstained corneas in a unique way compared to these gold standard techniques in ophthalmology. It provided background-free images of the three-dimensional interwoven distribution of the collagen deposits, with improved contrast compared to confocal microscopy. It also provided structural capability in intact corneas because of its high specificity to fibrillar collagen, with substantially larger field of view than transmission electron microscopy. Moreover, in vivo SHG imaging was demonstrated in Goto-Kakizaki rats.

Conclusions/Significance

Our study shows unambiguously the high potential of SHG microscopy for three-dimensional characterization of structural abnormalities in unstained corneas. Furthermore, our demonstration of in vivo SHG imaging opens the way to long-term dynamical studies. This method should be easily generalized to other structural remodeling of the cornea and SHG microscopy should prove to be invaluable for in vivo corneal pathological studies.

[Laser discission of a host descemet membrane after endothelial keratoplasty]

A case of YAG-laser discission of a hazy host descemet membrane left in anterior chamber after endothelial keratoplasty is presented.

Comparison of the effect of torsional and microburst longitudinal ultrasound on clear corneal incisions during phacoemulsification

PURPOSE

To compare incision integrity after clear corneal microcoaxial phacoemulsification using longitudinal and torsional ultrasound (US).

SETTING

Iladevi Cataract & IOL Research Centre, Ahmedabad, India.

DESIGN

Prospective randomized experimental clinical trial.

METHODS

Part 1 comprised an experimental study of rabbit eyes. Group 1 received longitudinal US. Group 2 received torsional US. The right eye of each rabbit served as a control. Samples were processed for histomorphology and collagen I denaturation by immunofluorescence. Part 2 comprised a clinical trial of patients. Group 1 received torsional US. Group 2 received longitudinal US. At the end of surgery, trypan blue 0.0125% was instilled. After 2 minutes, 0.1 mL of aqueous was aspirated and its optical density measured.

RESULTS

In part 1, incision histomorphology was comparable in both modalities. Collagen denaturation tests (immunofluorescence, dot blot analysis) showed no irregularity in collagen arrangement in either group. In Group 2, Descemet membrane was detached and endothelial cells were minimal at the roof of the incision. In part 2, trypan blue ingress into the anterior chamber was significantly greater in Group 1 than in Group 2 (mean 3.40 + 0.6 log units versus and 3.77 + 0.82 log units) (P<.007).

CONCLUSIONS

Incision histomorphology in the torsional group showed minimal Descemet membrane detachment and minimal endothelial cell loss at the roof of the incision. Minimal ingress of trypan blue into the anterior chamber was observed with torsional US, indicating better wound integrity than with longitudinal US.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Surgical repair of scrolled descemet's membrane detachment with intracameral injection of 1.8% sodium hyaluronate

We report the case of a 76-year-old woman with scrolled Descemet's membrane detachment (DMD) that was successfully treated by an intracameral injection of 1.8% sodium hyaluronate. During phacoemulsification cataract surgery, an undulating DMD involving the central cornea was observed and air tamponade into the anterior chamber was performed. The patient underwent surgical repair 2 weeks after the unsuccessful intracameral air injection. To increase the tamponade pressure and surface tension on the scrolled flap, viscoelastic material was injected into the air-filled anterior chamber. Corneal edema started subsiding clinically after the injection of sodium hyaluronate. Descemetopexy with sodium hyaluronate can successfully repair scrolled DMD and injection of viscoelastic material into the air-filled anterior chamber facilitates unfolding of the scrolled flap of DMD.

[Hemorrhagic Descemet's membrane detachment after viscocanalostomy]

INTRODUCTION

Viscocanalostomy is an option in the surgical treatment of glaucoma. This non-penetrating technique favours aqueous drainage through the Schlemm channel while avoiding filtering blebs and their related pathologies. Complications associated to this surgery are unusual, one of which is Decemet's membrane detachment (DMD) CLINICAL CASE: A 64 year-old female diagnosed with open-angle chronic glaucoma, whose had undergone a viscocanalostomy of the left eye. In the immediate postoperative period we noticed a hemorrhagic DMD in the lower temporal quadrant. After adopting a wait and see attitude, we did not find improvement 15 days after surgery and corneal edema was established with vision decrease. We proceeded to a surgical reapplication by means of Descemet's membrane micropuncture and SF6 injection into the anterior chamber and achieving an anatomical and functional improvement

DISCUSSION

We believe that the intrusion of viscoelastic material into the supradescemetic was a consequence of the high-pressure during the high-density hyaluronate injection. Hemorrhagic DMD management is mainly determined by its location, size and evolution. In our case, the posterior endothelial micropuncture and descematopexy by means of 20% SF6 injection into the anterior chamber was useful in resolving this complication.

Early changes in clear cornea incision after phacoemulsification: an anterior segment optical coherence tomography study

PURPOSE

We aimed to investigate the ultrastructures of clear corneal incisions 24 hours after phacoemulsification using anterior segment optical coherence tomography (AS-OCT).

METHODS

Sixty eyes of 60 patients scheduled for cataract surgery were randomly selected. All eyes underwent the same phacoemulsification procedure carried out by one experienced surgeon. Two-plane temporal clear corneal tunnel incisions were performed. The same types of intraocular lens and implant system were used in all patients. Images of the ultrastructures of the corneal incisions were taken using AS-OCT before and 1 day after surgery.

RESULTS

Corneal thickness increased at the incision site after surgery in all eyes (p < 0.001). Epithelial bulla in the incision region was seen in two eyes (3%). Gaping at the internal aspect of the corneal wound was seen in 42 eyes (70%). Eyes with gaping had thicker localized cornea (p = 0.002). Descemet's membrane detachment was seen in 49 eyes (82%); this seemed to be associated with lower preoperative intraocular pressure (p = 0.01).

CONCLUSIONS

 Anterior segment OCT provides sensitive and detailed measurements of the ultrastructures in clear corneal incision.

The histology of graft adhesion in descemet stripping with endothelial keratoplasty

PURPOSE

To describe the histologic findings of full-thickness corneas from penetrating keratoplasty (PK) in 10 patients with a prior history of Descemet stripping with endothelial keratoplasty.

DESIGN

Retrospective review of the histopathology of 10 PK specimens.

METHODS

We reviewed histologic sections stained with hematoxylin and eosin, periodic acid-Schiff, and colloidal iron stains from 10 PK specimens, which had been trisected and submitted in their entirety. Clinical data were abstracted from the medical record.

RESULTS

The interface between host and graft in most cases was barely perceptible with minimal changes in the degree of tissue eosinophilia, a subtle increase in keratocyte cellularity focally, or the presence of melanin granules within keratocytes. Residual host Descemet membrane (DM) was found in 8 of the 10 cases, most often at the edges of the graft. In no case did the presence of DM appear to hinder graft adhesion.

CONCLUSION

The adhesion of Descemet stripping with endothelial keratoplasty grafts is not associated with significant scarring or keratocyte proliferation. Contrary to previous assumptions, retained DM did not appear to hinder graft adhesion, raising the possibility that removal of DM may be unnecessary for endothelial transplantation.

A Rare Ocular Complication of Mumps: Kerato-Uveitis

PURPOSE

To report a child who developed kerato-uveitis associated with mumps infection.

METHODS

A prospective study of a child who was observed at the Department of Ophthalmology, Marmara University, Faculty of Medicine, during spring 2003.

RESULTS

An 11-year-old male patient noticed decreased vision in his left eye. His right eye was completely normal. Visual acuity was perception of hand movements in the left eye. Ocular examination revealed ciliary injection and diffuse hyperemia of the conjunctiva, interstitial keratitis characterized by prominent stromal infiltrates and edema, folds in the Descemet's membrane, and microcystic epithelial edema in his left eye. The patient had been diagnosed as having mumps 10 days previously by a pediatrician. Complete recovery of the keratitis occurred on the 10th day of topical steroid treatment.

CONCLUSIONS

Keratitis and/or iritis are rare complications of mumps. Corneal involvement is characterized by unilateral and painless interstitial keratitis that may cause a significant decrease in vision. Keratitis resolves with treatment and does not have any sequelae.

ORIGINAL ARTICLE Posterior Intracorneal Opacities in Patients with HIV Infection

PURPOSE

To describe a keratopathy in patients with the human immunodeficiency virus (HIV) infection.

METHODS

Retrospective review of ophthalmic and medical records, including laboratory evaluations, of seven patients with HIV infection and posterior intracorneal opacities.

RESULTS

Each patient had a bilateral peripheral keratopathy located at the level of the Descemet membrane that was unassociated with intraocular inflammation. All patients were receiving highly active antiretroviral therapy (HAART). All patients had elevations in their CD4+ T-lymphocyte counts due to HAART prior to presenting with the corneal opacities. Five of the seven patients had elevated serum cholesterol, triglycerides, or both. Best-corrected visual acuity was 20/25 or better in six of the seven patients at the time of diagnosis, and vision remained stable through the follow-up period in all patients (median follow-up: 25 months; range: 14-82 months). The corneal opacities remained unchanged in all seven over the follow-up period.

CONCLUSION

These patients have a bilateral keratopathy that appears to be non-progressive and has no effect on visual acuity.

Late corneal opacities in the syndrome of interstitial keratitis and vestibulo-auditory symptoms

Progressive clouding of the cornea may be a delayed complication of the interstitial keratitis-vestibuloauditory syndrome. Two illustrative cases are presented. The first case illustrates progressive opacification about aberrant vessels in the deep stroma presenting a characteristic dendritiform pattern. The second case shows that the opacification is due, in this case at least, to formation of connective tissue with inclusion of lipid crystals and fat along with the blood vessels. Descemet's membrane is also thickened several fold.

Descemet stripping automated endothelial keratoplasty in a 2-year-old child

Endothelial transplantation in the form of Descemet stripping endothelial keratoplasty (DSEK) or Descemet stripping automated endothelial keratoplasty (DSAEK) has rapidly become a popular, if not the preferred, method of treating endothelial failure. Although the need to perform corneal transplantation in children with endothelial dysfunction is relatively rare, this situation does arise, and in children still in the amblyogenic age group, rapid recovery from an essentially refractive-neutral corneal procedure carries significant advantages. We describe the use of DSAEK in a 2-year-old child who exhibited irreversible corneal edema from endothelial damage secondary to complicated cataract surgery. The rapid recovery and lack of induced astigmatism from DSAEK allowed for prompt institution of amblyopia therapy.

[Management in Descemet's membrane detachment after cataract surgery--case report]

Descemet's membrane detachment (DMD) is a rare, but serious complication of cataract surgery. It can cause permanent corneal edema that results in severe visual loss. Small detachments resolve with topical medical therapy within few weeks to few months. Larger detachments usually require surgical intervention. We present a case report of a patient with Descemet's membrane detachment that occurred one day after complicated phacoemulsification cataract surgery. At 3 months after surgery visual acuity was 3/50 and persistent corneal edema was observed. Anterior chamber tamponade with air under topical anesthesia successfully reattached Descement's membrane. The corneal edema regressed and the gas bubble resolved by the fifth day after surgery. Patient's left visual acuity was 5/12. The intraocluar pressure was 17 mmHg. We believe this method is safe, effective and results in fast visual acuity improvement.