Sachi Kojima

Filtering blebs using 3-dimensional anterior segment optical coherence tomography: A prospective investigation

IMPORTANCE Posttrabeculectomy changes in bleb parameters measured using 3-dimensional (3-D) anterior-segment optical coherence tomography (OCT) remain uncharacterized and might be related to postsurgical intraocular-pressure (IOP) control. OBJECTIVE To evaluate time-dependent posttrabeculectomy changes in filtering bleb parameters using 3-D anterior-segment OCT. DESIGN, SETTING, AND PARTICIPANTS This prospective observational study was conducted at Kumamoto University Hospital, Kumamoto, Japan. Patients with open-angle glaucoma who underwent uncombined fornix-based trabeculectomy at Kumamoto University Hospital between January 1, 2012, and October 31, 2012, were included. Twenty-nine eyes were enrolled, 23 of which were followed up for 1 year without additional glaucoma surgical procedures; 3 required additional glaucoma surgery. INTERVENTIONS Imaging filtering blebs using 3-D anterior-segment OCT. MAIN OUTCOMES AND MEASURES The primary end points were changes in bleb parameters including the position and width of the filtration openings on the scleral flap, the total bleb height, fluid-filled cavity height, bleb wall thickness, and bleb wall intensity, which were measured using 3-D anterior-segment OCT. The secondary end points were postsurgical IOP measured 0.5, 3, 6, and 12 months after trabeculectomy, and the effects of aqueous cytokine levels on the bleb parameters. RESULTS We observed increased total bleb height (0.82 to 1.25 mm; difference: 95% CI, 0.10 to 0.75; P = .01), bleb wall thickness (0.46 to 0.61 mm; difference: 95% CI, 0.02 to 0.28; P = .03), and distance from the top of the scleral flap to the filtration opening (1.69 to 2.16 mm; difference: 95% CI, 0.28 to 0.70; P < .001), as well as decreased width of the filtration opening (2.08 to 1.12 mm; difference: 95% CI, -1.75 to -0.49; P = .002) between 0.5 and 12 months posttrabeculectomy. The filtration openings tended to close from the fornix side of the scleral flap during the wound healing process. Moreover, the width of the filtration opening at 0.5 months posttrabeculectomy correlated with the IOP at 12 months (P = .02). The aqueous humor level of monocyte chemoattractant protein-1 was correlated with the width of the filtration opening at 3 and 6 months posttrabeculectomy. CONCLUSIONS AND RELEVANCE The width of the filtration opening at 0.5 months posttrabeculectomy correlated with the IOP at 12 months. The width of the filtration opening at the early stage may be a prognostic factor for long-term IOP control. Large-scale studies with longer follow-up periods are required.

Epithelial mesenchymal transition-like phenomenon in trabecular meshwork cells

The trabecular meshwork (TM) is a major component of the conventional outflow pathway and the excess extracellular matrix (ECM), and fibrosis in the TM causes increased outflow resistance. In this study, we first investigated the effects of several ECM components in the induction of an epithelial mesenchymal transition (EMT)-like phenomenon in TM cells. TM cells were isolated from cynomolgus monkeys (Macaca fascicularis). The cells were cultured in ECM-coated dishes and then subjected to both western blot analysis and immunocytochemistry to measure the levels of EMT-associated markers. Cell motility was assessed using wound healing and chemotaxis assays. We found that type I collagen, fibronectin and laminin induced the dissociation of cell-cell contact and elongation of actin stress fibers in the cultured monkey TM cells. In addition, following the same stimulation of the ECM, the expression of mesenchymal markers, such as fibronectin and α-smooth muscle actin, and the phosphorylation of Smad2 increased in the TM cells. Our results showed the significant acceleration of TM cellular motility following stimulation with type I collagen, fibronectin and laminin. These phenomena were inhibited by the c-Jun N-terminal kinase (JNK) inhibitor SP600125. In addition, siRNA against paxillin was transfected to evaluate the association between paxillin and the EMT-like phenomenon. The knockdown of paxillin expression by transfection with siRNA blocked the EMT-like alteration of the cellular characteristics and chemotaxis toward transforming growth factor-β2 in the cultured TM cells. Our results showed that the ECM-JNK-paxillin pathway induced an EMT-like phenomenon in TM cells, resulting in the abundant expression of fibronectin and activation of motility in TM cells. This EMT-like phenomenon could result in aberrant conditions in the aqueous outflow pathway in glaucomatous eyes.

Filtration bleb revision guided by 3-dimensional anterior segment optical coherence tomography.

Objective:To elucidate the usefulness of 3-dimensional anterior segment optical coherence tomography (3D AS-OCT) for bleb revision after trabeculectomy. Design:Case series. Participants:Two patients who underwent trabeculectomy and subsequent bleb revision. Methods:Three-dimensional AS-OCT and intraoperative observation. Main Outcome Measures:AS-OCT and intraoperative observation were analyzed to identify the filtration openings on the scleral flap margin and leaking points. Results:In 1 case with a leaking bleb, 3D AS-OCT examinations suggested the presence of numerous internal ostia (filtration openings). With 3D AS-OCT guidance, we carefully removed the leaking bleb with peripheral scar tissue. Histopathologic findings showed the presence of a thin bleb wall in the limbal conjunctiva corresponding to the point of aqueous leakage. In another case of an overhanging bleb, 3D AS-OCT examination revealed a thin bleb wall and multiloculated cystic structures. Histopathologic findings showed the presence of a thin region in the conjunctival epithelium in which connective tissue did not support the conjunctival epithelium, which seemed to correspond to the point at which oozing occurred. Conclusions:Three-dimensional AS-OCT enables evaluation of the internal morphology of filtration blebs and is useful for preoperative guidance for bleb revision.

Risk factors for hyphema after trabeculectomy with mitomycin C.

Purpose:To determine the risk factors for hyphema after trabeculectomy with mitomycin C (MMC). Patients and Methods:In total, 420 patients (420 eyes) with glaucoma who underwent trabeculectomy with MMC between June 1, 2005 and December 31, 2010 at Kumamoto University Hospital, Japan, were retrospectively evaluated. Hyphema after trabeculectomy was defined as the niveau formed by bleeding in the anterior chamber. Logistic multivariable analysis was applied to determine the risk factors for hyphema. Results:Of the 420 patients, 104 (24.8%) had hyphema. Neovascular glaucoma [NVG; odds ratio (OR)=2.404; P=0.0017] and anticoagulant or antiplatelet medication at trabeculectomy (OR=2.143; P=0.0274) were significant risk factors for hyphema. Of the 108 NVG patients, 43 (39.8%) had hyphema after trabeculectomy with MMC. In the subgroup analysis of NVG patients, neovascularization in the anterior chamber angle at trabeculectomy (OR=5.7886; P=0.0163) and anticoagulant or antiplatelet medication at trabeculectomy (OR=3.3325; P=0.0450) were risk factors for hyphema, whereas preoperative intravitreal bevacizumab injection significantly reduced the hyphema risk (OR=0.3568; P=0.0275). Conclusions:The risk factors for hyphema after trabeculectomy with MMC are independently associated with NVG and anticoagulant or antiplatelet medication. Neovascularization in the anterior chamber at trabeculectomy and anticoagulant or antiplatelet medication enhance the risk of hyphema developing in NVG patients, whereas preoperative injection of intravitreal bevacizumab reduces the likelihood.

Risk factors for choroidal detachment after trabeculectomy with mitomycin C.

Purpose To evaluate the risk factors for choroidal detachment after trabeculectomy with mitomycin C (MMC). Materials and methods We retrospectively evaluated 420 patients (420 eyes) with glaucoma who underwent trabeculectomy with MMC between June 1, 2005 and December 31, 2010 at Kumamoto University Hospital, Japan. Choroidal detachment after trabeculectomy was defined as a solid-appearing elevation of the retina and choroid. Logistic multivariable analysis was applied to determine the risk factors for choroidal detachment. The following factors were assessed: gender, age, subtypes of glaucoma, eye laterality, history of previous cataract surgery, preoperative intraocular pressure (IOP; mean of three Goldmann applanation readings recorded on different days), postoperative IOP (mean of seven Goldmann applanation readings recorded on 7 consecutive days after trabeculectomy), and postoperative laser suture lysis. Results Of the 420 patients, 79 (18.8%) revealed choroidal detachments. The mean period between trabeculectomy and choroidal detachment was 6.1 ± 3.6 days. The mean IOP at the time of the choroidal detachment was 5.5 ± 3.6 mmHg. Age (odds ratio [OR] = 1.028/year, P = 0.0068) and postoperative IOP (OR = 0.887/mmHg, P < 0.0001) were risk factors for choroidal detachment after trabeculectomy. The subgroup analysis for eyes with open angle glaucoma (201 patients) revealed that age (OR = 1.060/year, P = 0.0040) and postoperative IOP (OR = 0.898/mmHg, P = 0.0110) were significant risk factors for choroidal detachment after trabeculectomy with MMC. Conclusion Among glaucoma patients, older age and lower postoperative IOP are risk factors for choroidal detachment after trabeculectomy with MMC. In eyes with open angle glaucoma, older age and lower postoperative IOP are risk factors for choroidal detachment after trabeculectomy with MMC.

Intravital imaging of the cellular dynamics of LysM-positive cells in a murine corneal suture model

Background Corneal suturing is a surgical procedure used in patients with corneal trauma or transplants. It was reported that endogenous neutrophils are brightly labelled in gene-targeted mice expressing enhanced green fluorescent protein (eGFP) under the control of the endogenous lysozyme M promoter (LysM-eGFP mice). Methods We applied intravital imaging methods to analyse in vivo the dynamics of LysM-positive granulocytes (neutrophils) in LysM-eGFP mice with corneal sutures and examined their role in the elicitation of neutrophil infiltration. Results We found that in the presuturing state, neutrophils strongly positive for LysM were located in the periphery of the corneal stromal layer; none were present in the centre of the cornea. After introducing a corneal suture, neutrophils accumulated in limbal vessels and then migrated to the corneal side and the conjunctival side, suggesting that they derived from limbal vessels. Thereafter they accumulated towards the central corneal area, arriving at the suture about 7 h after its placement. Although corneal sutures may elicit the continuous infiltration of neutrophils, their number was markedly decreased by day 1 after suture removal and continued to decrease thereafter. Conclusions Our results showed that corneal sutures may elicit the continuous infiltration of neutrophils.

Heatstroke in patients with Parkinson’s disease

We present two Parkinson’s disease (PD) patients, who experienced heatstroke. Both patients manifested central nervous system dysfunction with elevated core temperature. Despite adequate lowering of the body temperature, multiorgan-dysfunction syndrome including encephalopathy, rhabdomyolysis, acute renal failure, acute respiratory failure, and disseminated intravascular coagulopathy was noted in one patient, leading to permanent neurologic damage. Because the ensuing multiorgan dysfunction could determine the functional prognosis in heatstroke patients, it is important to provide information about the prevention of heatstroke to patients, who are isolated or are severely disabled in the advanced stages of PD.

Tear fluid signs associated with filtration blebs, as demonstrated by three-dimensional anterior segment optical coherence tomography

Purpose To determine the clinical features of tear fluid signs associated with filtration blebs via three-dimensional anterior segment optical coherence tomography (3D AS-OCT). Methods In total, 152 eyes (130 patients) with glaucoma that underwent trabeculectomy with mitomycin C were evaluated retrospectively. We investigated tear fluid signs associated with filtration blebs, using 3D AS-OCT with custom software, and compared the findings of lower tear meniscus. We also analyzed postoperative intraocular pressure and the bleb parameters of filtration blebs between eyes with and without tear fluid signs. Results We found tear fluid signs associated with filtration blebs in 45 (30%) of 152 eyes. The mean postoperative intraocular pressure of the eyes with the tear fluid sign in a filtration bleb was significantly lower than that in eyes without the tear fluid sign (P<0.001). Blebs with tear fluid signs have more frequent identifiable filtration openings, greater total height, increased fluid-filled cavity height, and less wall intensity compared with blebs without these signs. Conclusion We identified tear fluid signs in AS-OCT images on or along filtration blebs that depended on bleb morphology. The occurrence of these signs may be related to the presence of functional blebs, which may thereby control postoperative intraocular pressure.

Fornix-based versus limbal-based conjunctival flaps in trabeculectomy with mitomycin C in high-risk patients

Purpose To compare the surgical outcomes of limbal-based and fornix-based trabeculectomy in eyes with a history of ocular incisional surgery. Methods Twenty-six eyes underwent limbal-based trabeculectomy (group LB), and were condition matched with 26 eyes that received fornix-based trabeculectomy (group FB). Surgical failure was recorded retrospectively if the intraocular pressure value was either ≥21, ≥18, and ≥15 mmHg (conditions A, B, and C, respectively) or <4 mmHg or if the patient required additional glaucoma surgery. Kaplan–Meier survival curve analysis was used to assess surgical failure. Results For condition A, the 2 year surgical success probabilities were 75.0% and 63.9% in groups FB and LB, respectively (P=0.124). The corresponding values were 55.0% and 61.7% (P=0.638) in condition B, and 55.0% and 57.0% (P=0.454) in condition C. The rates of bleb leakage, hypotony, choroidal detachment, and bleb-related infection were 11.5%, 26.9%, 50.0%, and 7.7% in group LB, respectively. The corresponding values in group FB were 30.8%, 23.1%, 46.2%, and 0.0%, which were not statistically different between the two groups. Conclusion No significant differences in surgical outcomes were observed between limbal-based and fornix-based trabeculectomy for patients with a history of incisional ocular surgeries.

Visualization of Intravital Immune Cell Dynamics After Conjunctival Surgery Using Multiphoton Microscopy.

PURPOSE To visualize intravital immune cell dynamics in the subconjunctival tissue during the wound-healing process using multiphoton microscopy. METHODS Gene-targeted mice expressing enhanced green fluorescent protein under the control of the endogenous lysozyme M promoter (LysM-eGFP mice) were anesthetized with isoflurane, and injured by a 10-0 nylon conjunctival suture. Vessels were visualized by intravenous injection of 70 kDa rhodamine-conjugated dextran. Using a multiphoton microscope, the three-dimensional images of the subconjunctival tissue were acquired every minute for 20 minutes before and 0.5, 3, 6, and 72 hours after injury. Raw imaging data were processed for four-dimensional images and analyzed for the number and the velocity of the LysM-eGFP-positive cells using Imaris software. RESULTS The intravital LysM-eGFP-positive cells and the red-labeled vessels were successfully visualized using a multiphoton microscope. The conjunctival and scleral collagen fibers were detected as secondary harmonic generation signals, which were colored blue. Compared with mice without injury, the number of LysM-eGFP-positive cells in the subconjunctival tissue after conjunctival surgery increased in a time-dependent manner. The cell velocities significantly increased until 3 hours after surgery (5.9 ± 3.2 μm/min; P < 0.0001) and the elevated level was sustained until 72 hours after injury (5.9 ± 3.3 μm/min). CONCLUSION This is the first report to visualize and evaluate intravital cellular dynamics during inflammation in the subconjunctival tissue using multiphoton microscopy. This technique may be a useful tool to characterize the molecular mechanisms of the wound-healing process after various ocular injuries, such as glaucoma surgery.