The microbiomes of the eyelid and buccal area of patients with uveitic glaucoma.

BACKGROUND: The microbiome could trigger inflammation leading to epigenetic changes and is involved in the pathophysiology of eye diseases; however, its effect on uveitic glaucoma (UG) has not been fully investigated. This study analysed the differences in eyelid and buccal microbiomes in patients with UG using next-generation sequencing. METHODS: The eyelid and buccal specimens of 34 UG and 25 control patients were collected. The taxonomic composition of the microbiome was obtained via 16S ribosomal DNA sequencing. Diversity and differential gene expression analyses (DEG) determined taxon differences between the microbiomes of UG and control groups. RESULTS: In both the eyelid and buccal microbiomes, alpha-diversity was lower in UG patients than controls, while beta-diversity in patients with UG was higher than in controls. DEG analysis of the eyelid microbiome revealed various taxa differences, including enrichment of Paenibacillus and Dermacoccus (p-value, 1.31e-6 and 1.55e-7, respectively) and depletion of Morganella and Lactococcus (p-value, 6.26e-12 and 2.55e-6, respectively) in patients with UG. In the buccal microbiome, taxa such as Lactococcus was significantly depleted (p-value, 1.31e-17), whereas Faecalibacterium was enriched in patients with UG (p-value, 6.12e-8). CONCLUSIONS: The eyelid and buccal microbiomes in patients with UG differ from controls, which raises concerns surrounding environmental influences on the pathogenesis of UG. The reduced Lactococcus in the eyelid and buccal area suggest that microbiota dysbiosis is associated with UG.

Management of XEN Gel Stent Exposure with Conjunctival Erosion via Rotational Conjunctival Flap and Amniotic Membrane Transplantation-A Case Report.

Background: Despite its proven effectiveness and safety profile, the XEN gel stent (Allergan Inc., CA, USA) for minimally invasive glaucoma surgery (MIGS) has a probability of postoperative complications, including postoperative hypotony, hyphema, stent migration, stent obstruction, bleb fibrosis, and fibrin formation. In particular, the use of adjunctive Mitomycin-C (MMC) might be associated with bleb-related complications, including conjunctival erosion, XEN gel stent exposure, and blebitis. However, there are few studies on XEN gel stent exposure and its management. We describe a case of XEN gel stent exposure with conjunctival erosion 18 months postoperatively, which resolved effectively after combination treatment with a rotational conjunctival flap and amniotic membrane transplantation. Case presentation: A 74-year-old Korean male patient with diabetes and hypertension underwent uncomplicated ab interno XEN gel stent implantation with a subconjunctival injection of 0.1 cc of 0.02% MMC and presented with low intraocular pressure (IOP) with a well-functioning filtering bleb. Periocular pain and tearing developed 18 months after the initial operation, with mild deterioration of visual acuity to 20/100. Despite conservative medical treatment, the conjunctival erosion was not relieved. Anterior segment optical coherence tomography (AS-OCT) revealed an exposed XEN gel stent with conjunctival erosion. We performed bleb revision surgery using a rotational conjunctival flap and amniotic membrane transplantation. Slit-lamp examination and AS-OCT showed a well-formed moderate bleb without leakage, and IOP continued to be well controlled (14 mm Hg with latanoprost) until six months after bleb revision. Conclusions: This case report highlights the importance of careful examination, including slit-lamp examination, the Seidel test, and AS-OCT, to identify accurate anatomical positioning and to monitor ocular surface changes after XEN gel stent implantation with MMC or 5-FU. Combination treatment (rotational conjunctival flap and amniotic membrane transplantation) may be relatively safe for persistent XEN gel stent exposure.

Differences in the eyelid and buccal microbiome of glaucoma patients receiving long-term administration of prostaglandin analog drops.

PURPOSE: To investigate the differences in the eyelid and buccal microbiomes between patients receiving long-term prostaglandin analogs for open-angle glaucoma (PG-OAG) and naïve-OAG patients by using metagenomics. METHODS: Eyelid and buccal samples were collected from 30 PG-OAG and 32 naïve-OAG patients. The taxonomic composition of the microbiome was obtained via 16S rRNA gene sequencing, operational taxonomic unit analysis, and diversity analysis. Differential gene expression analysis (DEG) and Bland-Altman (MA) plots were used to determine taxon differences between the microbiomes of PG-OAG and naïve-OAG patients. RESULTS: The eyelid microbiome showed marginally significant differences, while the alpha-diversity of the buccal microbiome showed significant differences between PG-OAG and naïve-OAG patients. However, the beta-diversity of both eyelid and buccal microbiomes was higher in PG-OAG patients than in naïve-OAG patients. The MA plot showed cluster differences in the eyelid microbiome. DEG analysis of the eyelid microbiome revealed various taxa differences, including enrichment of Azomonas, Pseudomonas, and Granulicatella in PG-OAG patients over naïve-OAG patients, as well as significant depletion of Delftia and Rothia. In the buccal microbiome in PG-OAG patients, taxa such as Rikenella and Stenotrophomonas were significantly enriched. CONCLUSION: Our findings suggest that the eyelid microbiome differs between PG-OAG and naïve-OAG patients, raising concerns regarding the eyelid environment in patients receiving these drugs. The overexpressed microbiome in the eyelid area suggests that microbiota may change after the administration of glaucoma medications in OAG.

Effects of refractive power on quantification using ultra-widefield retinal imaging.

BACKGROUND: Ultra-widefiled (UWF) retinal images include significant distortion when they are projected onto a two-dimensional surface for viewing. Therefore, many clinical studies that require quantitative analysis of fundus images have used stereographic projection algorithm, three-dimensional fundus image was mapped to a two-dimensional stereographic plane by projecting all relevant pixels onto a plane through the equator of the eye. However, even with this impressive algorithm, refractive error itself might affect the size and quality of images theoretically. The purpose of this study is to investigate the effects of refractive power on retinal area measurements (quantification) using UWF retinal imaging (Optos California; Dunfermline, Scotland, UK). METHODS: A prospective, interventional study comprised 50 healthy eyes. UWF images were acquired first without the use of a soft contact lens (CL) and then repeated with six CLs (+ 9D, +6D, +3D, -3D, -6D, and - 9D). Using stereographically projected UWF images, the optic disc was outlined by 15-17 points and quantified in metric units. We divided the subjects into three groups according to axial length: Groups A (22-24 mm), B (24-26 mm), and C (≥ 26 mm). The primary outcome was percentage change before and after use of the CLs. Secondary outcome was proportion of subjects with magnification effects, maximal changes > 10 %. RESULTS: The study population was 6, 28, and 16 eyes in each group. Overall changes for the measured area were not significantly different in the whole study population. Group C had a larger proportion of magnification effects compared to Groups A and B (50.0 %, 0 %, and 3.6 %, P = 0.020). Measured area with plus lenses was significantly higher in Group C (P < 0.001). CONCLUSIONS: The use of CLs might affect quantification of eyes with long axial length when using UWF images. Ophthalmologists should consider refractive error when measuring area in long eyes.

COMPARISON OF THE LAMINA CRIBROSA THICKNESS OF PATIENTS WITH UNILATERAL BRANCH RETINAL VEIN OCCLUSION AND HEALTHY SUBJECTS.

PURPOSE: To compare the lamina cribrosa (LC) thickness of healthy subjects and patients with unilateral branch retinal vein occlusion (BRVO), and to determine possible correlations between the LC thickness and the BRVO subtypes. METHODS: This prospective, cross-sectional study included a total of 46 patients with naive, untreated, unilateral BRVO and 31 healthy control subjects. The occlusion site was divided into two BRVO types: arteriovenous crossing BRVO (AV-BRVO) and optic nerve BRVO (ON-BRVO). The optic nerve head was scanned using enhanced-depth imaging with the Spectralis optical coherence tomography system. RESULTS: The mean LC thickness of both eyes in patients with BRVO was thinner than that of eyes (274.0 µm) of the healthy subjects (both, P < 0.001). Although the LC thickness of the BRVO-affected eyes was slightly thinner than that of the fellow eyes (237.0 µm vs. 241.4 µm, respectively), there was no statistically significant difference. In addition, there were no significant differences in the LC thicknesses of both eyes according to the site of occlusion. CONCLUSION: A thinner LC was observed in both eyes of unilateral BRVO patients compared with those of healthy subjects. This finding suggests that thin LC may contribute to the pathogenesis of BRVO as a local mechanical factor in addition to systemic factors.

Short-term in vivo morphological changes of amniotic membrane after fibrin glue-assisted pterygium surgery on anterior segment optical coherence tomography: a case presentation.

BACKGROUND: The evaluations of morphological changes of amniotic membrane (AM), even after successful AM transplantation surgery without complications, may be difficult. Moreover, there was no report regarding morphological changes after fibrin glue-assisted AM transplantation with pterygium excision. Here, we highlight and describe the use of spectral domain optical coherence tomography (OCT) for the evaluation of the morphological features of amniotic membrane (AM) and of associated in vivo structural changes after fibrin glue-assisted pterygium surgery. CASE PRESENTATION: All three patients underwent cryo-preserved AM transplantation using the permanent inlay technique (epithelial side up) with fibrin glue. In vivo morphological changes of AMs were evaluated using a spectral domain OCT equipped with an anterior segment imaging module (RTVue-100, Optovue, Inc., Fremont, CA, USA). Anterior segment OCT examinations demonstrated morphological changes, that is, re-absorption of fibrin glue or subconjunctival hemorrhage, migration of epithelium, and integration of AM into sclera, of AMs over first postoperative months. CONCLUSIONS: Anterior segment OCT might provide additional structural information, including quantitative and qualitative data, on AMs after pterygium surgery as compared with conventional slit-lamp examination.

Acute angle-closure glaucoma in a highly myopic patient secondary to Weill-Marchesani syndrome: histopathologic lens features.

The authors describe a case of acute angle-closure glaucoma in a highly myopic patient secondary to Weill-Marchesani syndrome (WMS) and histopathologic features of his lens. A 37-year-old male patient visited our clinic for ocular pain with elevated intraocular pressure (19/57 mmHg). The slit-lamp examination showed an inferiorly subluxated lens in the right eye, and anterior dislocated microspherophakia with corneolenticular contact in the left eye. The physical examination showed brachydactyly and relatively short stature. To control the IOP and to improve visual acuity, lens extraction, anterior vitrectomy, and scleral-sutured IOL implantation surgery were performed. To the best of our knowledge, this is the first histopathologic report of bilateral lens in a Korean patient with WMS. The pathologic specimens showed epithelial cell changes, hyaloid degeneration, and subcapsular cortical fiber changes. The authors attributed these changes to physical and mechanical factors because the lens is highly mobile and often comes in contact with the iris.

Penetrating ocular trauma associated with blank cartridge.

BACKGROUND: Blank cartridge guns are generally regarded as being harmless and relative safe. However recent published articles demonstrated that the gas pressure from the exploding propellant of blank cartridge is powerful enough to penetrate the thoracic wall, abdominal muscle, small intestine and the skull. And there has been a limited number of case reports of ocular trauma associated with blank cartridge injury. In addition, no report on case with split extraocular muscle injury with traumatic cataract and penetrating corneoscleral wound associated with blank cartridge has been previously documented. This report describes the case of patient who sustained penetrating ocular injury with extraocular muscle injury by a close-distance blank cartridge that required surgical intervention. CASE PRESENTATION: A 20-year-old man sustained a penetrating globe injury in the right eye while cleaning a blank cartridge pistol. His uncorrected visual acuity at presentation was hand motion and he had a flame burn of his right upper and lower lid with multiple missile wounds. On slit-lamp examination, there was a 12-mm laceration of conjunctiva along the 9 o'clock position with two pinhole-like penetrating injuries of cornea and sclera. There was also a 3-mm corneal laceration between 9 o'clock and 12 o'clock and the exposed lateral rectus muscle was split. Severe Descemet's membrane folding with stromal edema was observed, and numerous yellow, powder-like foreign bodies were impacted in the cornea. Layered anterior chamber bleeding with traumatic cataract was also noted. Transverse view of ultrasonography showed hyperechoic foreign bodies with mild reduplication echoes and shadowing. However, a computed tomographic scan using thin section did not reveal a radiopaque foreign body within the right globe. CONCLUSION: To our best knowledge, this is the first case report of split extraocular muscle injury with traumatic cataract and penetrating ocular injury caused by blank cartridge injury. Intraocular foreign bodies undetectable by CT were identified by B-scan ultrasonography in our patient. This case highlights the importance of additional ultrasonography when evaluating severe ocular trauma. And ophthalmologists should consider the possibility of penetrating injury caused by blank ammunition.

Recurrent symptomatic intraocular pressure spikes during hemodialysis in a patient with unilateral anterior uveitis.

BACKGROUND: The relationship between intraocular pressure (IOP) changes and hemodialysis has been evaluated for several decades. However, no report on an IOP rise in uveitis patients during hemodialysis has been previously documented. This report describes the case of an uveitis patient with repetitive IOP spikes associated with severe ocular pain during hemodialysis sessions, which resolved after glaucoma filtering surgery. CASE PRESENTATION: A 47-year-old male with diabetes and hypertension had complained of recurrent ocular pain in the left eye during hemodialysis sessions. A slit-lamp examination showed diffuse corneal epithelial edema with several white keratic precipitates and inflammatory cells (Grade 3+) in the anterior chamber of the left eye. No visible neovascularization or synechiae were visible on the iris or angle. Topical glaucoma eye-drops and intravenous mannitol before hemodialysis did not prevent subsequent painful IOP spikes in the left eye. At the end of hemodialysis, IOP averaged ~40 mmHg. After trabeculectomy with mitomycin C in the left eye, his IOP stabilized in the low-teens (range, 10-14 mmHg) and no painful IOP spikes occurred during hemodialysis over the first postoperative year. CONCLUSION: We present a case of recurrent painful IOP spikes during hemodialysis in a patient with unilateral anterior uveitis unresponsive to conventional medical treatment prior to hemodialysis. To our knowledge, this is the first case report of repetitive symptomatic IOP rise during hemodialysis in an uveitic glaucoma patient. This case highlights the importance of the awareness of the possibility that IOP may rise intolerably during hemodialysis in uveitis patients with a compromised outflow facility.

Five-Year Outcomes of Single Trabecular Microbypass Stent (iStent®) Implantation with Phacoemulsification in Korean Patients.

INTRODUCTION: This study reports the long-term intraocular pressure (IOP)-lowering efficacy and safety of a single trabecular microbypass stent (iStent®; Glaukos Corp., San Clemente, CA, USA) for medically controlled open-angle glaucoma in Korean patients. METHODS: This retrospective observational study included 42 eyes of 35 patients with primary open-angle glaucoma (POAG). All subjects underwent single first-generation iStent® implantation with phacoemulsification by a single surgeon with 5 years follow-up. The primary outcomes were changes in IOP and the number of antiglaucoma medications compared to the preoperative values. The secondary outcome was the proportion of eyes with IOP ≤ 18 mmHg without medication, ≤ 15 mmHg without medication, and ≤ 18 mmHg with or without medication. Adverse events and need for secondary glaucoma surgery were also recorded. RESULTS: The mean IOP decreased from 15.8 ± 2.8 to 13.8 ± 1.7 mmHg and the mean number of medications was reduced from 2.24 ± 1.18 to 0.83 ± 1.12, respectively, at year 5. At 3 and 5 years, 80.6% and 78.6% of eyes, respectively, were receiving fewer medications than preoperative numbers. In contrast, only 50% of eyes on four preoperative medications showed medication reductions at 5 years. At years 3 and 5, 61.3% and 53.5% of eyes achieved IOP ≤ 18 mmHg without medication, whereas 90.3% and 89.3% of eyes achieved ≤ 18 mmHg regardless of medication use, respectively. Four eyes required additional glaucoma surgery (two Ahmed glaucoma valve implantations, one trabeculectomy, and one XEN 45 Gel Stent implantation), and all were receiving four preoperative antiglaucoma medications. Transient IOP elevation (14.3%) was the most common complication, followed by five hyphema, one stent obstruction, one stent malposition, and one severe anterior chamber reaction. CONCLUSION: This study demonstrated a good safety profile and sustained IOP reduction after the implantation of a single trabecular microbypass stent (iStent®) with phacoemulsification in Korean patients. The majority of subjects with POAG showed a relatively good response; however, eyes receiving a higher number of medications preoperatively (especially four medications) had difficulty achieving a low target IOP.

Bleb Analysis Using Anterior Segment Optical Coherence Tomography and Surgical Predictors of XEN Gel Stent.

PURPOSE: To determine the early predictors of surgical success 6 months after XEN surgery among clinical parameters, including anterior segment optical coherence tomography (AS-OCT). METHODS: A total of 31 eyes with medically uncontrolled primary open-angle glaucoma or pseudoexfoliation glaucoma was enrolled retrospectively. Using AS-OCT, XEN tip location was categorized into intraconjunctival, intratenon, or uviform at day 1 and blebs were classified into no or low, high sparse, high thick, cystic, or mixed walls at month 6. Using slit-lamp photography, blebs were classified into no or low, localized avascular, diffuse avascular, localized vascular, or diffuse vascular blebs at month 6. Surgical success was defined as an intraocular pressure (IOP) of less than 14 mm Hg. RESULTS: Intraconjunctival and intratenon locations of the tip mostly created a high sparse wall, whereas the uviform type mostly created no or low wall and no or low bleb. The uviform type was linked to pseudoexfoliation glaucoma. A high sparse wall and diffuse avascular bleb showed a lower mean IOP than a high thick wall and localized vascular bleb. In the multivariate analysis, female sex and IOP at week 1 were early predictors of surgical success (8.45 times and 33.1% per 1 mm Hg-decrease, respectively). CONCLUSIONS: Bleb evaluation using AS-OCT is valuable to correlate tip location and bleb morphology with clinical profiles, considering that a lower early postoperative IOP is linked to surgical success. TRANSLATIONAL RELEVANCE: Bleb analysis using AS-OCT on day 1 could help to predict bleb morphology after 6 months, which is important to maintain the functioning bleb in the longer term.

Matrix Metalloproteinases and Glaucoma.

Matrix metalloproteinases (MMPs) are enzymes that decompose extracellular matrix (ECM) proteins. MMPs are thought to play important roles in cellular processes, such as cell proliferation, differentiation, angiogenesis, migration, apoptosis, and host defense. MMPs are distributed in almost all intraocular tissues and are involved in physiological and pathological mechanisms of the eye. MMPs are also associated with glaucoma, a progressive neurodegenerative disease of the eyes. MMP activity affects intraocular pressure control and apoptosis of retinal ganglion cells, which are the pathological mechanisms of glaucoma. It also affects the risk of glaucoma development based on genetic pleomorphism. In addition, MMPs may affect the treatment outcomes of glaucoma, including the success rate of surgical treatment and side effects on the ocular surface due to glaucoma medications. This review discusses the various relationships between MMP and glaucoma.

Differences in the eyelid and buccal microbiome between open-angle glaucoma and uveitic glaucoma.

PURPOSE: Microbiomes have immunoregulatory functions and may be involved in the pathophysiology of eye diseases. However, the effects of microbiomes on uveitic glaucoma (UG) and open-angle glaucoma (OAG) have not been sufficiently investigated. This study analysed differences in eyelid and buccal microbiomes between UG and OAG using metagenomic technology. METHODS: Eyelid and buccal specimens were collected from 34 UG and 62 OAG patients. The taxonomic composition of the microbiome was determined via 16S rRNA gene sequencing, operational taxonomic unit analysis and diversity analysis. Differential gene expression analysis (DEG) and principal component analyses (PCoA) determined taxon differences between the microbiomes of the UG and OAG patients. Subgroup analysis according to age and baseline IOP was performed. RESULTS: There was no significant difference in alpha-diversity between the microbiomes of UG and OAG patients. Further, PCoA revealed no differences in eyelid microbiome between the UG and OAG groups, but significant differences were found in buccal microbiome between the groups, especially in a subgroup of OAG patients with normal IOP. DEG analysis of the eyelid microbiome revealed various taxa differences, including the enrichment of Rhodococcus in UG samples over OAG samples. Taxa such as Lactobacillus and Proteus were significantly depleted (q-value = 9.98e-6 and q-value = 1.38 × 10-4 , respectively) in the buccal microbiome of UG patients, whereas Enterococcus was enriched (q-value = 5.26e-5 ). CONCLUSIONS: This study showed that the buccal microbiome in UG differs from that in OAG; reduced Lactobacillus was observed in UG. These results suggest that apart than OAG, microbiome composition may be a factor in the pathogenesis of UG.

Combined argon laser peripheral iridoplasty and Nd: YAG laser shock wave therapy for recurrent XEN gel stent obstruction due to iris incarceration: A case report.

INTRODUCTION: Despite its proven effectiveness and safety profile, the XEN Gel Stent (Allergan Inc., CA, USA) has a small lumen and is therefore likely to become occluded by fibrin, a blood clot, or even the iris. However, few studies have investigated XEN-iris occlusion and how to manage this condition. We describe the first case report of recurrent XEN gel stent obstruction by iris incarceration, which was resolved following a combined treatment with argon laser peripheral iridoplasty (ALPI) and low-energy neodymium-doped yttrium aluminum garnet (Nd: YAG) laser shock wave treatment. PATIENT INFORMATION: A 74-year-old Korean male underwent uncomplicated XEN gel stent implantation and presented with low intraocular pressure (IOP) with a well-functioning filtering bleb during the first postoperative week. On postoperative day 10, the XEN lumen was occluded by the iris and demonstrated an IOP spike of 33 mmHg. Despite the use of pilocarpine, the iris incarceration persisted. Therefore, surgery to reposition the XEN stent was attempted using a gonio-prism and intraocular forceps. After the first revision surgery, the IOP and stent position were stable for 2 weeks. However, recurrent partial obstruction of the stent by the iris, pigment dispersion into the intraluminal space, and an elevated IOP of 24 mmHg were observed later. DIAGNOSIS: Recurrent XEN gel stent occlusion by the iris and intraluminal pigment dispersion. INTERVENTIONS: Combined ALPI and low energy Nd: YAG laser shock wave therapy. OUTCOMES: IOP dropped from 24 mmHg to 10 mmHg immediately and continued to be well-controlled until 3 months later (range: 8-12 mmHg). CONCLUSIONS: To the best of our knowledge, this is the first case report of the efficacy of combined laser treatment for relieving recurrent XEN implant occlusion by the iris. This combination laser treatment might be a relatively safe rescue treatment to restore the patency of a XEN gel stent occluded by the iris, even in cases with recurrent XEN stent obstruction after surgical repositioning.

Clinical Outcomes After Second-Generation Trabecular Microbypass Stents (iStent inject®) with Phacoemulsification in Korean Patients.

INTRODUCTION: To evaluate the intraocular pressure (IOP)-lowering effect of second-generation trabecular microbypass stents (iStent® inject) with cataract extraction (combination group) and compare refractive changes in the combination group and the control (phacoemulsification only) group. METHODS: This retrospective case-control study included 36 eyes with cataract and medically controlled open-angle glaucoma with IOP < 21 mmHg and 100 nonglaucomatous eyes with cataract. Data were collected preoperatively and for 6 months postoperatively. Data included IOP, number of glaucoma medications, corrected distance visual acuity, and mean absolute error (MAE) from target refraction, and astigmatic vector analysis. Surgical success for the combination group was defined according to three criteria: (A) IOP < 15 mmHg without medication, (B) IOP < 18 mmHg without medication, and (C) IOP < 18 mmHg with or without medication. RESULTS: In the combination group, mean IOP was reduced from 15.1 ± 2.9 mmHg to 12.5 ± 2.0 mmHg, and the mean number of medications decreased from 1.9 ± 1.0 to 0.4 ± 0.8 at postoperative 6 months (both P < 0.001). Surgical success rates were 77.8%, 83.3%, and 97.2% at 6 months by criteria A, B, and C, respectively. Mean IOP was reduced from 14.3 ± 2.7 mmHg to 13.1 ± 2.1 mmHg at 1 month in the control group (P < 0.001). The MAE was 0.33 ± 0.26 D, and 83.3% of eyes had spherical equivalent difference within 0.50 D in the combination group (0.38 ± 0.33 D and 76.0% in the control group; P = 0.309 and P = 0.363, respectively). Preoperative and postoperative centroid values were 0.51 D @ 1° and 0.66 D @ 178°, respectively (0.23 D @ 176° and 0.66 D @ 1° in the control group). There were no statistical differences between the two groups with respect to preoperative and postoperative mean absolute values (P = 0.154 and P = 0.322, respectively). CONCLUSIONS: On the basis of our results using Korean real-world interim experience, iStent® inject with cataract extraction has favorable IOP-lowering effects and minimally impacts refractive outcomes.

Recanalization of XEN-45 gel stent occlusion with cortical material after phaco-XEN surgery using Nd: YAG laser treatment: A case report.

INTRODUCTION: The XEN Gel Stent (Allergan Inc., CA, USA) has been widely used in minimally invasive glaucoma surgery to lower intraocular pressure considering reasonable efficacy and safety profiles. However, the XEN gel stent could be occluded by fibrin, blood clots, or the iris due to its small lumen design for preventing postoperative hypotony. To date, only a few studies have assessed XEN occlusion after combined phacoemulsification with XEN gel implantation and how to manage this condition. We describe the first case report of XEN gel stent obstruction by cortical material, demonstrated by anterior segment optical coherence tomography (AS-OCT), which resolved effectively after low-energy neodymium-doped yttrium aluminum garnet (Nd: YAG) laser shock wave treatment. PATIENT INFORMATION: A 76-year-old Korean male patient underwent uncomplicated phaco-XEN-gel stent implantation and presented with low intraocular pressure (IOP) with a well-functioning filtering bleb during the first postoperative 4 days. On postoperative day 5, the XEN lumen was occluded by the cortical material, with an intraocular pressure elevation of 28 mm Hg. Slit-lamp examination revealed that cortical material was causing a block into the internal ostium of the XEN gel implant. AS-OCT examination also demonstrated the presence of hyper-reflective materials at the intraluminal portion and peritubular portion around the internal ostium of the XEN gel implant. DIAGNOSIS: XEN gel stent occlusion with cortical material after Phaco-XEN surgery. INTERVENTIONS: Low-energy Nd: YAG laser shock wave treatment. OUTCOMES: The IOP dropped from 28 mm Hg to 8 mm Hg immediately after treatment. Transient hypotony and a slightly shallow anterior chamber were noted over the 3 days after YAG laser treatment. The IOP continued to be well-controlled until 3 months later (range; 6 - 12 mm Hg). CONCLUSIONS: To the best of our knowledge, this is the first case report on the efficacy of Nd: YAG laser treatment for recanalization of XEN implant occluded by the cortex. Moreover, AS-OCT could provide additional clinical information for recanalization of the XEN gel stent.

Evaluation of ocular surface disease in elderly patients with glaucoma: expression of matrix metalloproteinase-9 in tears.

PURPOSE: To evaluate the symptoms and signs of ocular surface disease (OSD) and tear-film matrix metalloproteinase-9 (MMP-9) overexpression using point-of-care testing (InflammaDry test) in patients with primary open-angle glaucoma (POAG). METHODS: This prospective, case-control study included 67 patients diagnosed with POAG and 47 healthy control subjects. The OSD assessment included Schirmer-I test, the Oxford corneal stain scale, tear breakup time (TBUT), and the five-item dry eye questionnaire (DEQ-5). Measurement of extracellular MMP-9 level was performed using the InflammaDry test. The OSD parameters and MMP-9 expression levels were compared between the POAG group and the control group. Additional subgroup analysis in POAG group was performed according to number of topical glaucoma medications (Bottle 1, 2, or 3 medications). RESULTS: There were significant differences between the control and POAG groups for all OSD parameters. MMP-9 overexpression was observed in 71.6% of POAG group, whereas only 31.9% of control group showed MMP-9 overexpression. The subgroup analysis revealed that DEQ-5, Oxford stain score, Schirmer-I, and MMP-9 overexpression demonstrated no significant difference among the three groups. Abnormal TBUT (≤5 s) was observed in 37.5%, 59.1%, and 76.2% for each subgroup according to number of bottles (1, 2, and 3), and strong MMP-9 overexpression were also detected in 25.0%, 40.9%, and 61.9%, respectively (P = 0.032, P = 0.043). CONCLUSIONS: The use of preservative-containing medications may affect the ocular surface in patients with POAG. Graded measurement of tear-film MMP-9 could provide more information on OSD and might be a more useful marker for inflammation than then conventional results obtained by using an MMP-9 kit.

Analysis of oral microbiome in glaucoma patients using machine learning prediction models.

Purpose: The microbiome is considered an environmental factor that contributes to the progression of several neurodegenerative diseases. However, the association between microbiome and glaucoma remains unclear. This study investigated the features of the oral microbiome in patients with glaucoma and analyzed the microbiome biomarker candidates using a machine learning approach to predict the severity of glaucoma. Methods: The taxonomic composition of the oral microbiome was obtained using 16S rRNA gene sequencing, operational taxonomic unit analysis, and diversity analysis. The differentially expressed gene (DEG) analysis was performed to determine the taxonomic differences between the microbiomes of patients with glaucoma and the control participants. Multinomial logistic regression and association rule mining analysis using machine learning were performed to identify the microbiome biomarker related to glaucoma severity. Results: DEG analysis of the oral microbiome of patients with glaucoma revealed significant depletion of Lactococcus (P = 3.71e-31), whereas Faecalibacterium was enriched (P = 9.19e-14). The candidate rules generated from the oral microbiome, including Lactococcus, showed 96% accuracy for association with glaucoma. Conclusions: Our findings indicate microbiome biomarkers for glaucoma severity with high accuracy. The relatively low oral Lactococcus in the glaucoma population suggests that microbial dysbiosis could play an important role in the pathophysiology of glaucoma.

Clinical outcomes of trabecular microbypass stent (iStent) implantation in medically controlled open-angle glaucoma in the Korean population.

To evaluate the safety and efficacy [intraocular pressure (IOP)-lowering effect and medication use] of a single trabecular microbypass stent (iStent; Glaukos Corp, San Clemente, CA) for medically controlled open-angle glaucoma.This retrospective case series included 42 eyes of 34 patients with medically controlled open-angle glaucoma with IOP less than 21 mm Hg. Clinical outcomes analyzed were IOP, medication use, corrected distance visual acuity (CDVA), and surgical complications. Surgical success was defined according to 4 criteria: IOP < 21 mm Hg without medication; IOP < 18 mm Hg without medication; IOP < 15 mm Hg without medications; and IOP < 18 mm Hg with or without medication. Patients were followed for a minimum of 6 months postoperatively.Mean IOP was reduced from 15.8 ±â€Š2.8 mm Hg to 14.5 ±â€Š2.8 mm Hg (P < .001), while mean number of medications decreased from 2.2 ±â€Š1.2 to 0.8 ±â€Š1.1 at final visit (P < .001). Surgical success rates were 78.6%, 61.9%, 57.1%, and 97.6% at 6 months and 78.6%, 59.5%, 52.4%, and 95.2% at final visits according to criteria A, B, C, and D. Meanwhile, 59.5% of patients were medication-free at their final visit. The relative risk of surgical failure by Criteria B and C was 4.337 (95% confidence interval: 1.799-10.454) and 3.717 (95% confidence interval: 1.516-9.116) times greater in the higher-medication group (3 or more preoperative medications), respectively. CDVA was significantly improved from 0.41 ±â€Š0.10 to 0.09 ±â€Š0.07 LogMAR in the combined phacoemulsification and iStent implantation group (P < .001). There was no case whose vision was threatened (vision loss of 2 or more lines) or who showed severe complications after surgery.Single trabecular microbypass stent implantation was effective in reducing IOP and medication usage in patients with open-angle glaucoma with a low preoperative IOP. Our results imply that it is more difficult to achieve low target IOP control in eyes with higher numbers of preoperative medications.

Delayed-Onset Retrobulbar Hemorrhage and Glaucoma Drainage Device Extrusion in a Patient on Anticoagulation: A Case Report.

Both retrobulbar hemorrhage and plate extrusion are uncommon complications after implantation of a glaucoma drainage device (GDD). There are no published reports on extrusion of an Ahmed glaucoma valve after delayed-onset retrobulbar hemorrhage in Korea. Herein, we report a case of spontaneous extrusion of a GDD after delayed-onset retrobulbar hemorrhage in a patient on anticoagulation. The case was a 72-year-old man with open-angle glaucoma and proliferative diabetic retinopathy, as well as systemic hypertension, atrial fibrillation, congestive heart failure due to coronary heart disease, and chronic kidney disease, who underwent combined Ahmed glaucoma valve implantation and cataract extraction surgery in his right eye. The body remained in position with control of intraocular pressure for 2 months. On day 67 (5 days post-coronary artery bypass surgery), he complained of decreased visual acuity, periorbital swelling, bloody discharge, and limited extraocular movement. One month later, the body was extruded with a scleral flap tear. Therefore, delayed-onset retrobulbar hemorrhage should be kept in mind in patients on anticoagulants after insertion of a GDD.