Osamu Hieda

Assessment of epithelial integrity and cell viability in epithelial flaps prepared with the epi-LASIK procedure.

PURPOSE: To assess the histological integrity and cell viability in epithelial flaps prepared with epikeratomes. SETTING: Department of Ophthalmology, Kyoto Prefectural University of Medicine and The Baptist Eye Clinic, Kyoto, Japan. METHODS: Epithelial flaps were prepared by epi‐LASIK surgery. After immediate fixation, they were examined by light and electron microscopy. To assess cell viability in fresh epithelial flaps, biostaining experiments were performed using propidium iodide (PI), calcein‐AM, and Hoechst 33342 dye. In addition, some epithelial flaps were organ‐cultured for 24 hours. RESULTS: Light and electron microscopy showed that most of the inspected areas showed nuclei and cytoplasm at significantly reduced density and discontinuity of the basement membrane. Biostaining experiments showed that approximately 90% of the basal cells in epithelial flaps were PI‐positive dead cells; organ cultures showed detachment of basal cells from the epithelial flap after 24 hours of incubation. CONCLUSION: Most basal cells in epithelial flaps prepared with different epikeratome devices were dead.

Comparison of central corneal thickness measurements by Orbscan II and Pentacam after corneal refractive surgery.

PurposeTo compare the accuracy of postoperative pachymetry between Orbscan II (Bausch & Lomb) scanning-slit corneal topography/pachymetry and the Pentacam (Oculus) rotating Scheimpflug camera.MethodsCentral corneal thickness (CCT) was determined in 24 patients (48 eyes) before and after laser in situ keratomileusis (LASIK) or Epipolis LASIK (Epi-LASIK) procedures. All eyes were examined by Orbscan II and Pentacam prior to refractive surgery and at the first, fourth, and twelfth week postoperatively. The residual CCT (RCCT) measured by each instrument was compared to the theoretical RCCT.ResultsOn the first, fourth, and twelfth week after the refractive surgery, the mean RCCT measurements by Orbscan II were 413 ± 72, 435 ± 65, and 440 ± 69 µm, respectively. Those of Pentacam were 434 ± 51, 436 ± 53, and 438 ± 50 µm, respectively. Orbscan II measurements at the postoperative first and fourth week were significantly smaller than the theoretical RCCT (P < 0.01, P < 0.01, paired t test). There was no statistical difference between the theoretical RCCT and the Pentacam measurements at any stage.ConclusionThe Orbscan II measurement values of postoperative corneas tended to be thinner than the theoretical values, but not those of the Pentacam.

Evaluation of intraocular pressure change after laser in situ keratomileusis using the pressure phosphene tonometer

Purpose: To evaluate the applicability of pressure phosphene tonometry in measuring intraocular pressure (IOP) after laser in situ keratomileusis (LASIK). Setting: Baptist Eye Clinic, Kyoto, Japan. Methods: Thirty‐six eyes of 22 consecutive patients who had had LASIK for myopia were enrolled in this prospective comparative study. The mean age of the patients was 32.6 years ± 9.0 (SD). The IOP was measured using the pressure phosphene tonometer (FPT), Goldmann applanation tonometry (GAT), and noncontact tonometry (NCT). The patients themselves took measurements with the FPT before and 1 week after surgery. One‐way analysis of variance followed by a Bonferroni/Dunn multiple comparison post hoc test was administered to compare the preoperative and postoperative measurements with each tonometer. These data were represented graphically using a method described by Bland and Altman. The relationship between each tonometric change and the central corneal thickness (CCT) or keratometry (K) changes after LASIK were evaluated with by Pearson correlation coefficient. Results: Statistically significant differences were found between preoperative and postoperative measurements with GAT and NCT but not with FPT. Preoperative and postoperative FPT readings conformed to the British Standard for reproducibility of a standard test method for IOP estimation. No significant correlation between FPT changes and CCT or K changes was found. Conclusions: Pressure phosphene tonometry measures IOP through the upper eyelid, and changes in corneal shape do not appear to have an effect on the IOP. The IOP measurements with FPT were constant before and after LASIK.

Anterior segment optical coherence tomography findings of acute angle-closure glaucoma in Vogt-Koyanagi-Harada disease

Ultrasound biomicroscopy (UBM) is reported to be useful for the evaluation of the anterior chamber, chamber angle, and ciliary body. However, a UBM examination is diffi cult and invasive for the patient. The new Visante (Carl Zeiss Meditec, Oberkochen, Germany) imaging system using anterior segment optical coherence tomography (AS-OCT) makes it possible to visualize the anterior segment noninvasively to obtain quantitative information. We report a patient with acute angle-closure glaucoma associated with Vogt-Koyanagi-Harada (VKH) disease in whom imaging with AS-OCT was carried out to evaluate the anterior segment.

Measuring of ocular wavefront aberration in large pupils using OPD-scan.

Wavefront analysis using a scanning slit refractometer (the OPD-Scan™) was evaluated in both artificial and human eyes, in comparison with the Hartmann-Shack wavefront sensor (H-S) currently often used. Comparison of different methods and configurations carried out in the artificial eyes yielded basically the same results in moderate refractive error cases. There was a closer match between the RMS (root mean square) wavefront error obtained by OPD-Scan and H-S in the 6 mm pupils than in the 4 mm pupils of the same normal human eyes. Although OPD-Scan employs a different approach in determining aberration, the aberration value is similar to that of H-S, especially in large pupils.

Clinical Outcomes of Phototherapeutic Keratectomy in Eyes With Thiel-Behnke Corneal Dystrophy

PURPOSE To investigate the functional and morphologic midterm outcome of phototherapeutic keratectomy (PTK) for Thiel-Behnke corneal dystrophy diagnosed by gene-mutation analysis. DESIGN Retrospective, single-center clinical study. METHODS Between July 2001 and May 2010, 10 consecutive PTKs were performed in 10 eyes of 5 patients (2 male, 3 female; mean age: 55 ± 13 years) with superficially accentuated opacities caused by Thiel-Behnke corneal dystrophy and were followed up for at least 12 months (range: 12-108 months). Main outcome measures included (1) best-corrected visual acuity (BCVA), (2) uncorrected visual acuity (UCVA), (3) spherical equivalent, and (4) recurrence rate. The probability of recurrence of Thiel-Behnke corneal dystrophy after PTK was calculated using the Kaplan-Meier method for survival analysis. RESULTS The p.Arg555Gln mutation was found within the TGFBI gene in all 5 patients. Average logarithm of minimal angle of resolution (logMAR) BCVA change was -0.55 ± 0.26. Average logarithm UCVA change was -0.54 ± 0.31. In 5 of the 10 eyes, recurrence of central superficial opacification was clinically identified during the follow-up periods, and in 4 of those 5 eyes, the level of the recurrence was so significant that the visual acuity was reduced more than 2 lines. The maximum follow-up period of the 1 eye without significant post-PTK recurrence was 108 months. CONCLUSIONS PTK is a successful therapy for Thiel-Behnke corneal dystrophy, and results in midterm stable visual acuity and corneal transparency. Unlike in Reis-Bücklers corneal dystrophy cases, PTK delays the need for more invasive surgical intervention in Thiel-Behnke corneal dystrophy.

Infectious keratitis caused by fluoroquinolone-resistant Corynebacterium.

Corynebacterium is an aerobically growing, asporogenous, non-partially acid-fast, irregularly shaped gram-positive rod that colonizes the skin and mucous membranes. Since it is frequently isolated from the ocular surface of healthy persons, it is usually recognized as non-pathogenic, even when isolated from eyes with keratitis. However, recent reports indicate the etiologic role of this organism. We report the management of a case of keratitis related to fluoroquinolone-resistant Corynebacterium and discuss the pathogenicity of fluoroquinolone-resistant Corynebacterium.

Nasal and conjunctival screening prior to refractive surgery: an observational and cross-sectional study

Objectives To investigate bacterial flora of clinically healthy conjunctiva and nasal cavity among patients prior to refractive surgery, as well as the characteristics of patients with methicillin-resistant Staphylococcus aureus (MRSA) colonisation. Design Observational and cross-sectional study. Setting A single-centre study in Japan. Participants 120 consecutive patients pre-refractive surgery. Primary and secondary outcome measures methods Samples were obtained from the right conjunctival sac and the nasal cavity of 120 consecutive patients prior to refractive surgery and were then measured for the levels of the minimum inhibitory concentration (MIC) of antibiotics. Patients were interviewed regarding their occupation, family living situation and any personal history of atopic dermatitis, asthma, smoking or contact lens wear. Results Propionibacterium acnes (P. acnes) (32.5%) and Staphylococcus epidermidis (4.2%) were detected from the conjunctival sac. S. epidermidis was the most commonly isolated (68.3%) in the nasal cavity. Of the 30 patients (25.0%) with colonisation by S. aureus, 2 patients, both of whom were healthcare workers with atopic dermatitis, were found to be positive for MRSA in the nasal cavity. A history of contact lens wear, asthma or smoking, as well as patient gender and age, was not associated with MRSA colonisation. Conclusions There were only 2 patients who were colonised with MRSA, both of whom were healthcare workers with atopic dermatitis. P. acnes was predominantly found in the conjunctival sac. Further study is needed to investigate the involvement between nasal and conjunctival flora, and risk factors for infectious complications.

Microincision Hydrophobic Acrylic Aspheric Toric Intraocular Lens for Astigmatism and Cataract Correction.

PURPOSE To evaluate the efficacy and safety of a new acrylic one-piece toric intraocular lens (IOL). METHODS This prospective multicenter clinical trial included 93 eyes of 61 patients that were implanted with a hydrophobic acrylic toric IOL from 2010 to 2012 and followed for 1 year. This IOL uses the platform of a microincision one-piece aspheric IOL, the NY-60 IOL (HOYA, Tokyo, Japan), with three increments in cylindrical power (NHT15, 1.5 diopters [D]; NHT23, 2.25 D; and NHT30, 3.0 D). The inclusion criterion was preoperative corneal astigmatism from 0.75 to 3.00 D. The primary endpoint was uncorrected distance visual acuity (UDVA) of 0.0 logMAR (20/20 Snellen) or better 6 months postoperatively. In addition to UDVA, corrected distance visual acuity (CDVA), residual astigmatism, stability of the IOL alignment, need of realignment, and the rate of Nd:YAG laser capsulotomy were evaluated up to 1 year postoperatively. Errors in astigmatic correction were assessed using Alpins vector analysis. RESULTS The primary endpoint was achieved in 54.8% of eyes. One year postoperatively, the logMAR UDVAs were 0.02 ± 0.13, 0.05 ± 0.17, and 0.09 ± 0.14 with models NHT15, NHT23, and NHT30, which corresponds to 0.96 (19/20 Snellen), 0.89 (18/20 Snellen), and 0.82 (16/20 Snellen), respectively. One year postoperatively, the residual astigmatism was 0.66 ± 0.58 D. In each evaluation, the mean absolute change in the position of the axis mark was between 1.93° and 2.32°. Three eyes required repositioning of the IOL axis and 2 eyes received Nd:YAG laser capsulotomy. The correction error showed an undercorrection with against-the-rule astigmatism and overcorrection with with-the-rule astigmatism. CONCLUSIONS The new one-piece toric IOL provided desirable clinical outcomes and stability in eyes with corneal astigmatism.

The existence of dead cells in donor corneal endothelium preserved with storage media

Aim To investigate the viability of donor corneal endothelial cells (CECs) preserved in storage media by histological examination. Methods Twenty-eight donor corneas were obtained from SightLife Eye Bank (Seattle, Washington), and redundant peripheral portions of those corneas were used for histological examination after removal of the centre corneal graft for transplantation. To assess cell viability in the corneal endothelium, biostaining experiments were performed using propidium iodide, calcein-AM, Hoechst 33 342, annexin V, anti-vimentin antibody and toluidine blue. Results Histological analysis of the endothelium showed that the cytoplasm of dead cells had low-intensity fluorescence and that their nuclei stained red, while almost all living cells had green cytoplasm and blue-stained nuclei. The mean dead cell rate in the 28 donor corneas was 4.9%±3.3% (mean ±SD) (range: 0.6%–10.5%). The propidium iodide-positive cells stained positive for annexin V, negative for vimentin and pale for toluidine blue. After the specimens were incubated in a culture medium, the red nucleus dead cells dropped off from the level of the blue nucleus living cells. Conclusion Our findings showed the existence of dead cells in storage-media-preserved donor corneal endothelium and that they dropped off after incubation, thus suggesting that the decrease of CECs following keratoplasty may be related to the presence of dead cells.