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Ophthalmology | 2013

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

Akira Kobayashi; Hideaki Yokogawa; Natsuko Yamazaki; Toshinori Masaki; Kazuhisa Sugiyama

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.


Cornea | 2015

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

Akira Kobayashi; Noriaki Murata; Hideaki Yokogawa; Natsuko Yamazaki; Toshinori Masaki; Kazuhisa Sugiyama

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.


Clinical Ophthalmology | 2014

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

Hideaki Yokogawa; Akira Kobayashi; Natsuko Yamazaki; Toshinori Masaki; Kazuhisa Sugiyama

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.


Clinical Ophthalmology | 2012

Bowman’s layer encystment in cases of persistent Acanthamoeba keratitis

Hideaki Yokogawa; Akira Kobayashi; Natsuko Yamazaki; Yasuhisa Ishibashi; Yosaburo Oikawa; Masaharu Tokoro; Kazuhisa Sugiyama

Background The purpose of this study was to report Acanthamoeba encystment in Bowman’s layer in Japanese cases of persistent Acanthamoeba keratitis (AK). Methods Laser confocal microscopic images of the cornea were obtained in vivo from 18 consecutive eyes from 17 confirmed AK patients. Retrospectively, 14 cases treated over 4 months were categorized as a nonpersistent group and three cases that required prolonged therapy for more than 6 months were categorized as a persistent group. Clinical outcomes based on final best-corrected visual acuity were retrospectively analyzed, and selected confocal images were evaluated qualitatively for abnormal findings. Results The final best-corrected visual acuity was significantly lower (P < 0.01) for patients in the persistent group compared with that in the nonpersistent group. At the initial visit, in vivo confocal microscopy demonstrated Acanthamoeba cysts exclusively in the epithelial layer in both the nonpersistent group (80%) and the persistent group (100%). At a subsequent follow-up visit, numerous Acanthamoeba cysts were observed in the epithelial cell layer and in Bowman’s layer in all patients with persistent AK, but Acanthamoeba cysts were undetectable in all cases with nonpersistent AK tested. Conclusion Invasion of cysts into Bowman’s layer was characteristically observed in patients with persistence of AK. This finding suggests that invasion of Acanthamoeba cysts into Bowman’s layer may be a useful predictor for a persistent clinical course.


Clinical Ophthalmology | 2015

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

Akira Kobayashi; Hideaki Yokogawa; Natsuko Yamazaki; Toshinori Masaki; Kazuhisa Sugiyama

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.


Clinical Ophthalmology | 2014

Endothelial keratoplasty with infant donor tissue

Akira Kobayashi; Hideaki Yokogawa; Natsuko Yamazaki; Toshinori Masaki; Kazuhisa Sugiyama

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.


Japanese Journal of Ophthalmology | 2013

Identification of cytomegalovirus and human herpesvirus-6 DNA in a patient with corneal endotheliitis

Hideaki Yokogawa; Akira Kobayashi; Natsuko Yamazaki; Kazuhisa Sugiyama

PurposeTo report the case of a patient with unilateral corneal endotheliitis in which both cytomegalovirus (CMV) and human herpesvirus-6 (HHV6) DNA was identified in the aqueous humor.CaseA 67-year-old man with corneal endotheliitis OD was referred to us for decreased visual acuity. Local corneal stromal edema, pigmented keratic precipitates, a coin-shaped lesion and minimal anterior chamber reaction were observed by slit-lamp biomicroscopy. Cells with owl’s eye appearance in the endothelial cell layer were observed by in vivo laser confocal microscopy. The patient had rheumatoid arthritis, which was treated by oral prednisolone and intravenous abatacept. Polymerase chain reaction analysis of aqueous humor samples detected both CMV and HHV6 DNA, but not other HHVs. Treatment with topical ganciclovir and systemic valganciclovir resulted in a clear cornea.ConclusionsA patient with corneal endotheliitis had both CMV and HHV6 DNA identified in the aqueous humor. Although both viruses were identified in this case, clinical manifestations resembled CMV corneal endotheliitis, and it was unclear whether HHV6 could affect the clinical course. Systemic abatacept and corticosteroid therapy might play a positive role in cases with both CMV and HHV6 DNA in this corneal endotheliitis.


Ophthalmology | 2013

In vivo laser confocal microscopy findings of radial keratoneuritis in patients with early stage Acanthamoeba keratitis.

Akira Kobayashi; Hideaki Yokogawa; Natsuko Yamazaki; Yasuhisa Ishibashi; Yosaburo Oikawa; Masaharu Tokoro; Kazuhisa Sugiyama

OBJECTIVE To investigate in vivo corneal changes of keratoneuritis in early stage Acanthamoeba keratitis (AK) using in vivo laser confocal microscopy. DESIGN Single-center, prospective, clinical study. PARTICIPANTS Thirteen eyes (12 patients; 5 men and 7 women; mean age ± standard deviation, 22.3 ± 4.2 years) with keratoneuritis resulting from early stage AK were included in this study. TESTING In vivo laser confocal microscopy was performed, paying special attention to keratoneuritis. MAIN OUTCOME MEASURES Selected confocal images of corneal layers were evaluated qualitatively for shape and degree of light reflection of abnormal cells and deposits. RESULTS In all patients, Acanthamoeba cysts were observed clearly in the basal epithelial cell layer as highly reflective round particles with a diameter of 10 to 20 μm. Bowmans layer infiltration of Acanthamoeba cysts was observed in only 1 case, and no cases showed stromal or nerve infiltration of Acanthamoeba cysts. In the stroma, all cases showed highly reflective activated keratocytes forming a honeycomb pattern; these changes were significant around the keratoneuritis. Infiltration of inflammatory cells, possibly polymorphonuclear cells, was observed along with keratocyte bodies in all cases. Numerous highly reflective spindle-shaped materials were observed around the keratoneuritis. Most notably, highly reflective patchy lesions were observed around the keratoneuritis in 11 cases (84.6%). Inflammatory cells also were observed in the endothelial cell layer in 4 cases (30.8%). CONCLUSIONS In vivo laser confocal microscopy identified consistent corneal abnormalities around keratoneuritis in early stage AK patients, of which highly reflective patchy lesions may be characteristic of keratoneuritis. Further morphologic studies of corneas with early stage AK in a larger number of patients may elucidate the clinical significance of radial keratoneuritis and may help us to understand the interaction between Acanthamoeba organisms and host corneal cells or nerves.


Clinical Ophthalmology | 2013

Clinical features of single and repeated globe rupture after penetrating keratoplasty.

Noriaki Murata; Hideaki Yokogawa; Akira Kobayashi; Natsuko Yamazaki; Kazuhisa Sugiyama

Background In this paper, we report our experience of the clinical features of single and repeated globe rupture after penetrating keratoplasty. Methods We undertook a retrospective analysis of single and repeated globe ruptures following keratoplasty in eight eyes from seven consecutive patients referred to Kanazawa University Hospital over a 10-year period from January 2002 to March 2012. We analyzed their ophthalmic and demographic data, including age at time of globe rupture, incidence, time interval between keratoplasty and globe rupture, cause of rupture, complicated ocular damage, and visual outcome after surgical repair. Results Five patients (71.4%) experienced a single globe rupture and two patients (28.6%) experienced repeated globe ruptures. Patient age at the time of globe rupture was 75.4 ± 6.8 (range 67–83) years. Four of the patients were men and three were women. During the 10-year study period, the incidence of globe rupture following penetrating keratoplasty was 2.8%. The time interval between penetrating keratoplasty and globe rupture was 101 ± 92 months (range 7 months to 23 years). The most common cause of globe rupture in older patients was a fall (n = 5, 79.8 ± 3.7 years, all older than 67 years). Final best-corrected visual acuity was >20/200 in three eyes (37.5%). In all except one eye, globe rupture involved the graft-host junction; in the remaining eye, the rupture occurred after disruption of the extracapsular cataract extraction wound by blunt trauma. Conclusion Preventative measures should be taken to avoid single and repeated ocular trauma following penetrating keratoplasty.


Cornea | 2014

In vivo imaging of coin-shaped lesions in cytomegalovirus corneal endotheliitis by anterior segment optical coherence tomography.

Hideaki Yokogawa; Akira Kobayashi; Natsuko Yamazaki; Kazuhisa Sugiyama

Purpose: The aim of this study was to investigate in vivo corneal changes of coin-shaped lesions in cytomegalovirus corneal endotheliitis using anterior segment optical coherence tomography (AS-OCT). Methods: Two eyes of 2 patients (69- and 71-year-old men), with polymerase chain reaction–proven CMV corneal endotheliitis presenting coin-shaped lesions, were included in this study. AS-OCT examination was performed on the initial visit and at follow-up visits by paying special attention to the coin-shaped lesions. Selected AS-OCT images of the cornea were evaluated qualitatively for changes in the shape and degree of light reflection. Results: In both cases, coin-shaped lesions were observed at the corneal endothelial surface as clusters of fine precipitates using slit-lamp biomicroscopy. Using AS-OCT, high-resolution images of the putative coin-shaped lesions were successfully obtained in both patients as an irregularly thickened highly reflective endothelial cell layer. After anti-CMV treatment, the coin-shaped lesions were resolved as assessed by slit-lamp biomicroscopy and AS-OCT in both patients. Conclusions: High-resolution AS-OCT provides novel and detailed visual information of coin-shaped lesions in patients with CMV corneal endotheliitis. Visualization of coin-shaped lesions by AS-OCT may be a useful adjunct to the diagnosis and follow-up of CMV corneal endotheliitis.

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Yosaburo Oikawa

Kanazawa Medical University

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Naoko Tachi

Aichi Medical University

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