Toshinori Masaki

In Vivo Laser Confocal Microscopy after Descemet's Membrane Endothelial Keratoplasty

OBJECTIVE To investigate the in vivo corneal changes in patients with bullous keratopathy who underwent Descemets membrane endothelial keratoplasty (DMEK) with the use of in vivo laser confocal microscopy. DESIGN Single-center, retrospective clinical study. PARTICIPANTS Five eyes of 4 patients (3 men, 1 women; mean age, 61.3 ± 9.6 years) with bullous keratopathy who had undergone successful DMEK were enrolled in this study. TESTING In vivo laser confocal microscopy was performed before and 1, 3, and 6 months after DMEK. MAIN OUTCOME MEASURES Selected confocal images of corneal layers were evaluated qualitatively and quantitatively for the degree of haze and the density of deposits. Subepithelial haze, donor-recipient interface haze, donor-recipient interface particles, and host stromal needle-shaped materials were graded on a scale of 4 categories (grade 0 = none, grade 1 = mild, grade 2 = moderate, grade 3 = severe) at each time point. Time trends of the outcomes were graphically displayed and evaluated with Mantel-Haenszel trend test. RESULTS The following were observed preoperatively in all patients: slight corneal epithelial edema, moderate subepithelial haze, keratocytes in a honeycomb pattern, and tiny needle-shaped materials in the stroma. After DMEK, moderate subepithelial haze persisted during the follow-up period. Needle-shaped materials had a tendency to decrease after DMEK. Most notably, donor-recipient interface haze and donor-recipient interface particles were barely noticeable after DMEK as early as 1 month postoperatively. CONCLUSIONS In vivo laser confocal microscopy can identify subclinical corneal abnormalities after DMEK, such as subepithelial haze, host stromal needle-shaped materials, and minimum donor-recipient interface haze/particles. These abnormalities seemed subtle compared with Descemet stripping automated endothelial keratoplasty; this may explain the superior postoperative visual acuity after DMEK. Further studies with this technology in a large number of patients and long-term follow-up are needed to fully understand the long-term corneal changes after DMEK. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Evaluation of internationally shipped prestripped donor tissue for descemet membrane endothelial keratoplasty by vital dye staining.

Purpose: The aim of this study was to evaluate endothelial cell damage of internationally shipped prestripped donor tissue for Descemet membrane endothelial keratoplasty (DMEK) using vital dye staining. Methods: Six internationally shipped prestripped DMEK donors were stained with trypan blue and were subsequently photographed before they were cut with a trephine. Quantitative analysis assessment of endothelial damage of the donor graft area (8.0 mm in diameter) was performed using Adobe Photoshop CS6 Extended software. Seven internationally shipped precut Descemet stripping automated endothelial keratoplasty (DSAEK) donors were used as controls. Results: No statistical differences were noted between prestripped DMEK donors and precut DSAEK donors in mean donor age (67.7 vs. 56.4 years, P = 0.222), mean donor endothelial cell density (2687.3 vs. 2894.6 cells, P = 0.353), and death-to-preservation time (405.3 vs. 558.4 minutes, P = 0.173). However, the mean time of death-to-experiment time in DMEK donors was significantly longer than that of DSAEK donors (8.7 vs. 6.6 days, P = 0.031). Mean endothelial cell damage of prestripped DMEK donors was as low as 0.3%. However, DMEK donor endothelial damage (0.3%) was significantly higher compared with that of precut DSAEK donor tissue (0.01%, P = 0.029). Conclusions: Although endothelial damage of internationally shipped prestripped donor tissue for DMEK was higher than that of precut DSAEK donor, it was extremely low. Further evaluation using another vital dye and clinical studies may be needed to confirm this study.

Surgical therapies for corneal perforations: 10 years of cases in a tertiary referral hospital

Purpose To report surgical therapies for corneal perforations in a tertiary referral hospital. Methods Thirty-one eyes of 31 patients (aged 62.4±18.3 years) with surgically treated corneal perforations from January 2002 to July 2013 were included in this study. Demographic data such as cause of corneal perforation, surgical procedures, and visual outcomes were retrospectively analyzed. Results The causes of corneal perforation (n=31) were divided into infectious (n=8, 26%) and noninfectious (n=23, 74%) categories. Infectious causes included fungal ulcer, herpetic stromal necrotizing keratitis, and bacterial ulcer. The causes of noninfectious keratopathy included corneal melting after removal of a metal foreign body, severe dry eye, lagophthalmos, canaliculitis, the oral anticancer drug S-1, keratoconus, rheumatoid arthritis, neurotrophic ulcer, atopic keratoconjunctivitis, and unknown causes. Initial surgical procedures included central large corneal graft (n=17), small corneal graft (n=7), and amniotic membrane transplantation (n=7). In two cases the perforation could not be sealed during the first surgical treatment and required subsequent procedures. All infectious keratitis required central large penetrating keratoplasty to obtain anatomical cure. In contrast, several surgical options were used for the treatment of noninfectious keratitis. After surgical treatment, anatomical cure was obtained in all cases. Mean postoperative best corrected visual acuity was better at 6 months (logMAR 1.3) than preoperatively (logMAR 1.8). Conclusion Surgical therapies for corneal perforations in our hospital included central large lamellar/penetrating keratoplasty, small peripheral patch graft, and amniotic membrane transplantation. All treatments were effective. Corneal perforation due to the oral anticancer drug S-1 is newly reported.

the use of endoillumination probe-assisted Descemet membrane endothelial keratoplasty for bullous keratopathy secondary to argon laser iridotomy

Purpose To report the first case of Descemet membrane endothelial keratoplasty (DMEK) for bullous keratopathy (BK) secondary to argon laser iridotomy (ALI). Patient A 71-year-old woman presented with decreased visual acuity in her right eye due to BK secondary to ALI that was performed 10 years prior. Results Phacosurgery was performed first, followed by successful DMEK 4 months later. A DMEK shooter was used for donor insertion, which allowed for a stable anterior chamber during donor insertion, even when the anterior chamber was quite shallow. Also, removal of edematous epithelial cells and endoillumination probe-assisted DMEK was quite useful to visualize DMEK graft on the background of the dark brown iris seen in Asian eyes. The patient’s best corrected visual acuity rapidly increased from 20/200 to 25/20 after 1 month, with complete resolution of corneal edema. Conclusion We reported the first successful DMEK case for BK secondary to ALI. The use of a DMEK shooter for donor insertion and endoillumination assistance to visualize the DMEK graft was a useful technique for BK secondary to ALI.

Endothelial keratoplasty with infant donor tissue

Here we report a case of endothelial keratoplasty with infant donor tissue obtained after brain death. A 52-year-old man with endothelial dysfunction of unknown cause in the right eye underwent non-Descemet stripping automated endothelial keratoplasty (nDSAEK) with tissue from an infant donor (2 years). Intraoperative and postoperative complications were recorded. Best corrected visual acuity and donor central endothelial cell density were recorded preoperatively and postoperatively. Infant donor tissue preparation with a microkeratome set at 300 μm was successful; the donor tissue was extremely elastic and soft compared with adult tissue. The central endothelial cell density of the infant donor tissue was as high as 4,291 cells/mm2. No complications were observed during donor tissue (8.0 mm in diameter) insertion with the double-glide technique (Busin glide with intraocular lens sheet glide) or any of the other procedures. Best corrected visual acuity improved from 1.7 logMAR (logarithm of the minimum angle of resolution; 0.02 decimal visual acuity) preoperatively to 0.2 logMAR (0.6) after 6 months and 0.1 logMAR (0.8) after 1 year. The central endothelial cell density after 6 months was 4,098 cells/mm2 (representing a 4.5% cell loss from preoperative donor cell measurements), and the central endothelial cell density after 1 year was 4,032 cells/mm2 (6.0% decrease). Infant donor tissue may be preferably used for DSAEK/nDASEK, since it may not be suitable for penetrating keratoplasty or Descemet membrane endothelial keratoplasty.

Rationale for performing penetrating keratoplasty rather than DSAEK in patients with bullous keratopathy in Japan.

BACKGROUND AND OBJECTIVE To analyze the rationale for performing penetrating keratoplasty (PK) rather than Descemets stripping automated endothelial keratoplasty (DSAEK) in patients with bullous keratopathy (BK) in Japan. PATIENTS AND METHODS A total of 136 eyes of 130 patients with consecutive BK were enrolled. Patients treated by DSAEK were categorized as the DSAEK group. The remaining patients were considered unsuitable for DSAEK due to the presence of risk factors, and were treated by PK (PK group). In both groups, the number of the patients and the causes of BK were analyzed. Also, specifically in the PK group, the reasons for not performing DSAEK were analyzed. RESULTS The causes of BK differed significantly between the two groups (P < .001). Risk factors considered unsuitable for DSAEK include significant stromal scarring, iris abnormalities, and lens abnormalities. CONCLUSION For successful DSAEK, risk factors and contraindications should be carefully evaluated before surgery.

A 10-year review of underlying diseases for endothelial keratoplasty (DSAEK/DMEK) in a tertiary referral hospital in Japan

Purpose To report a 10-year review of endothelial keratoplasty (EK) procedures, Descemet’s stripping automated endothelial keratoplasty (DSAEK) and Descemet’s membrane endothelial keratoplasty (DMEK), and underlying diseases at a tertiary referral hospital in Japan. Study design A single-center, retrospective case series. Methods We retrospectively reviewed all medical records of bullous keratopathy (BK) surgically treated by EK (DSAEK/DMEK) at Kanazawa University Hospital from January 2007 to December 2016. Changes or modifications to the annual number of EK procedures and underlying diseases were analyzed. Results During this period, 320 EK procedures (DSAEK: 288 cases, DMEK: 32 cases) were performed on 250 patients. Total annual EKs gradually increased from 19 to 45 cases between 2007 and 2016. The annual number of DSAEKs was stable, although the proportion of DSAEKs to other procedures decreased significantly as re-DSAEKs and DMEKs increased. BK after argon laser iridotomy (ALI) was the leading cause in 2007, followed by Fuchs’ endothelial dystrophy (FED) and failed penetrating keratoplasty. In 2016, BK after trabeculectomy (TLE) was most prevalent, followed by failed DSAEK, failed penetrating keratoplasty, and pseudophakic BK. The decreased ALI and FED, and increased BK after TLE and failed DSAEK were statistically significant. Conclusion The distribution of EK procedures (DSAEK/DMEK) and underlying diseases changed over 10 years at a tertiary referral hospital in Japan. The proportion of re-DSAEK and DMEK increased among all EK procedures. Most significantly, among the underlying diseases, decreased ALI and FED and increased TLE and failed DSAEK were observed. Extended multicenter analysis may further elucidate the changes in EK procedures and the causes of BK in Japan.

Development of a Donor Tissue Holding Technique for Descemet’s Membrane Endothelial Keratoplasty Using a 25-Gauge Graft Manipulator

Purpose: To report a modified surgical technique called the “donor tissue holding technique for Descemet’s membrane endothelial keratoplasty (DMEK)” using a newly developed 25-gauge graft manipulator. Methods: Six consecutive patients exhibiting endothelial dysfunction were enrolled and treated by DMEK. In brief, after insertion of a DMEK donor into the anterior chamber, the edge of the roll was grasped using a graft manipulator and this grasp was maintained throughout the centering and opening of the roll (holding technique). The following parameters were evaluated in comparison to the previous 10 consecutive DMEK cases in which the no touch technique was used: time of graft unfolding, incidence of intra-/postoperative complications, and best spectacle-corrected visual acuity (BCVA) and endothelial cell density (ECD) 6 months after the procedure. Results: In both technique groups, neither intra- nor postoperative complications were noted in any case. No differences were observed between the two groups in postoperative BCVA (p = 0.88). Also, no differences were observed between the two groups in postoperative ECD (holding technique group: 2,108.3 cells/mm2, no touch technique group: 1,491.7 cells/mm2) (p = 0.08) Most notably, the time of graft unfolding prior to filling with air was significantly reduced in the holding technique group (305.5 s) compared to that of the no touch technique group (1,310.0 s; p = 0.01). Conclusions: This donor tissue holding technique enabled rapid and safe DMEK in a reproducible manner, even in Asian eyes with shallow anterior chambers with high vitreous pressure.

In vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta

Objective To report the in vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta (OI) with special attention to the abnormality of Bowman’s layer and sub-Bowman’s fibrous structures (K-structures). Patients and methods Two patients (67-year-old male and his 26-year-old son) with OI type I were included in this study. Slit lamp biomicroscopic and in vivo laser confocal microscopic examinations were performed for both patients. Central corneal thickness and central endothelial cell density were also measured. Results Although the corneas looked clear with normal endothelial density for both eyes in both patients, they were quite thin (386 μm oculus dexter (OD) (the right eye) and 384 μm oculus sinister (OS) (the left eye) in the father and 430 μm OD and 425 μm OS in the son). In both patients, slit lamp biomicroscopic and in vivo laser confocal microscopic examination showed similar results. Anterior corneal mosaics produced by rubbing the eyelid under fluorescein were completely absent in both eyes. In vivo laser confocal microscopy revealed an absent or atrophic Bowman’s layer; a trace of a presumed Bowman’s layer and/or basement membrane was barely visible with high intensity. Additionally, K-structures were completely absent in both eyes. Conclusion The absence of K-structures and fluorescein anterior corneal mosaics strongly suggested an abnormality of Bowman’s layer in these OI patients.