Comparison of Bleb Morphology following PRESERFLO® MicroShunt and Trabeculectomy Using Anterior Segment OCT.

Trabeculectomy has traditionally been upheld as the gold standard in glaucoma surgery, but recent advancements, including the PRESERFLO® MicroShunt, have introduced less invasive techniques to mitigate complications and reduce intraocular pressure (IOP). The examination of bleb morphology post-filtering surgery is critical for modulating wound healing and ensuring long-term success. While previous evaluations of PRESERFLO-generated blebs have relied on data from trabeculectomy blebs, the differing surgical techniques used in PRESERFLO and trabeculectomy surgeries suggest potential variations in bleb morphologies. This study conducted a comparative analysis of blebs resulting from PRESERFLO and trabeculectomy procedures. Retrospective descriptive assessments using the Jenaer Bleb Grading System were performed, along with quantitative evaluation using eight-dimensional parameters utilizing anterior segment OCT. We included 93 eyes (57 following PRESERFLO, 36 following trabeculectomy). In the descriptive assessment, PRESERFLO-generated blebs exhibited fewer conjunctival cysts (3.5% vs. 22.2%, p = 0.007) and cavernous changes (10.5% vs. 30.5%, p = 0.021) compared to trabeculectomy. Quantitatively, overall bleb dimensions were comparable (maximal bleb height, width, and length, p > 0.05 for all). However, PRESERFLO blebs displayed a shallower (0.52 ± 0.24 vs. 0.67 ± 0.3 mm, p = 0.017) yet longer (4.12 ± 1.54 vs. 3.23 ± 1.64 mm, p = 0.024) episcleral lake. A thicker bleb wall (1.52 ± 0.46 vs. 1.10 ± 0.37 mm, p < 0.001) along with more posteriorly positioned blebs (distance to limbus = 6.16 ± 1.36 vs. 4.87 ± 1.34 mm, p < 0.001) were observed following PRESERFLO. This study illuminates the nuanced morphological differences between PRESERFLO and trabeculectomy blebs. Understanding these distinctions is vital, empowering clinicians to make informed postoperative decisions and avoid misinterpretation of bleb morphology.

Factors Correlated With Mid-Term Morphology of Functional Blebs Following Implantation of Preserflo MicroShunt Using AS-OCT.

Purpose: Evaluating bleb morphology is crucial after glaucoma filtering surgery. Advances in anterior segment optical coherence tomography (AS-OCT) allow for objective assessment. While various parameters differentiate functional from failed blebs, limited information exists regarding variations within functional blebs. This study aimed to identify factors influencing morphology of functional blebs following implantation of Preserflo MicroShunt. Methods: Eyes with functional blebs after Preserflo were retrospectively included. Age, gender, lens status, preoperative intraocular pressure (pre-IOP) and number of glaucoma medications were documented along with biometric measurements as axial length (AL), white-to-white distance, and anterior chamber depth. Postoperative data included time elapsed since surgery (TaS) and postoperative IOP (post-IOP). Bleb dimensions were measured using AS-OCT including maximal bleb height (MBH), width, length (MBL), bleb wall thickness (BWT), and bleb distance to limbus (DtL) along with dimensions of episcleral lake (maximal height, width [MLW], and length). Linear regression models were applied to correlate these parameters with bleb dimensions. Results: Included were 50 eyes from 50 patients. Mean IOP decreased from 25.3 ± 10.0 to 11.9 ± 3.0 mm Hg after 278.5 ± 221.9 days after surgery. MBH correlated negatively with age (unstandardized coefficients [uSC] = -0.012) and TaS (uSC = -0.001, P = 0.008 for both). BWT correlated negatively with age (uSC = -0.013, P = 0.02), MBL with AL (uSC = -0.566, P = 0.01) and MLW with pre-IOP (uSC = -0.073, P = 0.02). DtL exhibited a positive correlation with post-IOP (uCS = 0.136, P = 0.02). Conclusions: Morphology of functional blebs might be influenced by multiple factors such as age, TaS, AL, and pre- and post-IOP. Translational Relevance: Age, time after surgery, axial length, and preoperative and postoperative IOP could affect the morphology of a functional bleb; hence, these factors should be taken into consideration when making treatment decisions.

A Comparative Analysis of Morphology and Dimensions of Functional Blebs following PRESERFLO-Microshunt and XEN-Gel-Stent, a Study Using Anterior Segment OCT.

Evaluation of bleb morphology is a vital part of successful filtration glaucoma surgery. The PRESERFLO-MicroShunt (PRESERFLO) and XEN-Gel-Stent (XEN) are drainage devices implanted using different surgical approaches (ab externo and ab interno, respectively), potentially resulting in distinct bleb morphology. Understanding these morphological differences is essential for postoperative care. In this study, we retrospectively examined functioning blebs following PRESERFLO and XEN implantation using high-resolution anterior segment OCT imaging. Qualitative assessment utilizing the Jenaer Bleb Grading System and quantitative assessment measuring 12 parameters representing bleb dimensions were conducted, and the results were compared between the two groups. A total of 80 eyes from 80 patients were included (41 after PRESERFLO, 39 after XEN). Functioning blebs following PRESERFLO exhibited a higher frequency of hyperreflective tenon changes compared to XEN (31.7% vs. 10.3%, respectively, p = 0.02) and a lower frequency of cavernous changes (17.1% vs. 35.9%, p = 0.05). Additionally, PRESERFLO blebs showed a higher frequency of visible episcleral lakes (92.7% vs. 30.8%, p < 0.001). Furthermore, PRESERFLO blebs demonstrated larger height (2.13 ± 0.5 vs. 1.85 ± 0.6 mm, p = 0.03), width (10.31 ± 2.3 vs. 9.1 ± 2.3 mm, p = 0.02), length (9.13 ± 1.8 vs. 8.24 ± 1.9 mm, p = 0.04), posterior location relative to the limbus (6.21 ± 1.2 vs. 5.21 ± 1.8 mm, p = 0.005), and a thicker bleb wall (1.60 ± 0.5 vs. 1.1 ± 0.4 mm, p = 0.004). Functioning blebs following PRESERFLO and XEN displayed morphological distinctions, likely attributed to variations in surgical techniques (ab externo vs. ab interno) and stent dimensions. These morphological differences should be taken into consideration when evaluating blebs, as they could impact assessments of bleb functionality and influence decisions regarding postoperative interventions.

Results of open bleb revision as management of primary bleb failure following XEN 45 gel stent and Preserflo™ Microshunt.

PURPOSE: The success of filtering surgery as in XEN-Gel-Stent (XEN) and Preserflo-Microshunt (PF) depends mainly on a functioning bleb. Primary bleb failure (PBF) is not uncommon and can be treated with needling or open bleb revision (OBR). The aim of the study is to compare surgical outcomes of OBR after XEN and PF. METHODS: Eyes which received OBR as management of PBF following implantation of XEN or PF were retrospectively included. Intraocular pressure (IOP), number of IOP lowering medications (NoM), and success rates (SR) were compared between groups. Complete and qualified success were defined as IOP ≤18mmHg and a reduction of >20%, without and with medications, respectively. RESULTS: 29 eyes after XEN and 23 eyes after PF were included. Six months following OBR, IOP reduced from 24.2±4.7 to 13.5±4.6 after XEN and from 27.3±8.7 to 15.9±5.8mmHg after PF (both p<0.001). NoM did not change (0.7±1.3 to 0.4±0.8 after XEN and 1.2±1.3 to 1.0±1.5 after PF, p>0.05 for both). Complete SR were higher after XEN than after PF (58.6% vs. 30.4%, p=0.04). Complications were mild and managed mainly conservatively. Additional glaucoma surgery was needed in 17% and 30% of eyes after XEN and PF, respectively (p=0.26). CONCLUSION: Although OBR was effective as management of PBF following XEN and PF, SR were higher after XEN than after PF along with comparable safety profile. The change of the surgical approach from ab interno during XEN-Implantation to ab externo during OBR seems to enhance SR compared to PF, where both interventions are done ab externo.

Symptomatic familial primary iris cysts at the pupillary margin in three consecutive generations: A case series.

Case series purpose: Iris cysts are uncommon lesions, most of them are iris pigment epithelial (IPE) cysts which typically manifest in adults as unilateral single cysts, are typically asymptomatic and rarely require treatment. The most frequent location of IPE cysts is the iris periphery and the iridociliary sulcus, whereas pupillary cysts are rare. This observational case series aims to describe a unique occurrence of bilateral pupillary IPE cysts in three consecutive generations of a single family. Observations: The series describes eight patients of a single family with no consanguineous marriage. All patients have IPE cysts with remarkable abnormally-shaped pupils. The patients were examined at the slit-lamp and imaged with anterior segment optical coherence tomography. Three brothers (14, 19 and 28 years old) were symptomatic and suffered from hemeralopia and reduced visual acuity. ND-YAG laser was successful in relieving the symptoms in the two younger brothers. No recurrence or refill of the cysts occurred after laser application and no intra- or ppostoperative complications were observed during a 9-month follow-up. The older family members showed spontaneously shrunken IPE cysts. Conclusions and Importance: IPE cysts are considered idiopathic with an unclear origin. The rare familial incidence of the cysts suggests an autosomal dominant heredity pattern. Many theories were proposed to explain the origin of cysts and none is conclusive. Their principal clinical significance is their similarity to pigmented iris tumors, but they might also cause visual symptoms. Treatment modalities vary from less invasive chemical compounds and ND: YAG laser application to more invasive surgical procedures with disparate efficacy and safety. In the case of multiple cysts, examination of other family members is worthy even when asymptomatic and cardiac consultation of affected patients is warranted as IPE cysts may proclaim a coexisting cardiovascular abnormality, such as familial aortic dissection.

[Bleb morphology using optical coherence tomography : After primary implantation of XEN gel stent and open conjunctival revision]. / Morphologie des Sickerkissens mittels optischer Kohärenztomographie : Nach primärer Implantation von XEN-Gel-Stent und offener Bindehautrevision.

BACKGROUND: The implantation of a XEN gel stent is an innovative method for filtration surgery using an ab interno approach. The morphological evaluation of the resulting bleb is decisive for surgical success. Bleb revision is frequently needed after XEN implantation and might affect the bleb morphology. Aim of this study was to examine bleb morphology using anterior segment OCT (AS-OCT) and analyze the morphological differences of blebs after primary XEN implantation and after bleb revision. MATERIAL AND METHODS: Included were eyes that underwent XEN implantation (Pr-X) or bleb revision after XEN (Re­X group). An AS-OCT of blebs was performed and images were classified using a novel classification system (the Jenaer bleb grading system, JBGS). Frequency of different tomographic patterns (M) and their correlation with intraocular pressure (IOP) were analyzed. RESULTS AND DISCUSSION: A total of 69 eyes (40 in the Pr­X and 29 in the Re­X groups) were included. At the conjunctival level, the most common M in both groups was subconjunctival spaces (M-C2) followed by intraconjunctival cysts (C1) and no conjunctival changes (C0). No differences of frequencies between the two groups or of IOP between the three Ms were seen. At the tenon level, the most commonly seen Ms in the Pr­X group were hyporeflective and cavernous changes (M-T2, T3) followed by no changes (M0) and hyperflective changes (T1). In the Re­X group, the M­T1 and T2 were most commonly seen followed by T3 and T0. The M­T2 and T3 in the Pr­X group and the M­T1 and T2 in the Re­X group correlated with lower IOP. An episcleral lake (M-ES1) was seen significantly less frequently in the Pr­X group compared with Re­X group where it correlated with lower IOP CONCLUSION: The hyperreflective changes at the tenon level and the presence of an episcleral lake were seen more frequently following bleb revision compared with primary XEN implantation and correlated with lower IOP. The interpretation of bleb morphology using AS-OCT should only be done considering the surgical approach used.

Novel Bleb Classification Following Ab Interno Implantation of Gel-Stent Using Anterior Segment Optical Coherence Tomography.

PRCIS: A novel qualitative tomographical classification for bleb after implantation of XEN-Gel-Stent using ab interno approach is presented. Association of anatomic patterns to intraocular pressure (IOP) and success rates (SR) illustrates that anterior segment optical coherence tomography can be useful tool in clinical guidance. PURPOSE: To present a novel classification of bleb resulting from ab interno implantation of XEN-Gel-Stent and report association of tomographical patterns with IOP and SR. MATERIALS AND METHODS: A cross-sectional 1-armed study of patients receiving XEN-Gel-Stent. Tomographical changes in the bleb area were studied using swept-source optical coherence tomography in an early (d 29-90 postsurgery) and late (starting from d 91 postsurgery) phase. Frequency of patterns and their association with IOP and SR (defined as IOP<18 mmHg without medications) were studied. RESULTS: One hundred eleven examinations of 49 blebs (49 patients) were included. Three tomographical patterns at conjunctival, 4 at tenons capsule, and 2 at episcleral level were characterized. Most frequent conjunctival pattern was subconjunctival spaces (56.3% and 53.2% in the early and late phase, respectively) and associated with lower IOP (13.0±6.0 mmHg) and higher SR (89%) but only in the early phase compared with other conjunctival patterns ( P <0.05). At tenons capsule level, the hyporeflective pattern was most frequent (50% and 51.9% in early and late phase) followed by the cavernous pattern. Both patterns associated with lower IOP and higher SR compared with hyper-reflective or loss of tenon changes ( P <0.005). Most blebs showed no episcleral lake (87.5% and 89.9% in early and late phase). No difference of IOP and SR was noted compared with those showing an episcleral lake. CONCLUSION: A practical and clinically relevant novel classification system is proposed to tomographically describe and classify blebs after implantation of XEN-Gel-Stent. Certain patterns were associated with lower IOP and higher SR.

Changes of retinal oxygen saturation during treatment of diabetic macular edema with a pre-defined regimen of aflibercept: a prospective study.

PURPOSE: To study the effect of anti-VEGF therapy for diabetic macular edema (DME) on retinal oxygen saturation (O2S) and its correlation with functional and anatomical changes of retinal tissue. METHODS: An interventional prospective single group study. Included were 10 eyes of 10 patients with visually significant DME which received a fixed regimen of intravitreal aflibercept every 4 weeks for 5 months, followed by 3 injections every 8 weeks, and were controlled monthly. Visual acuity (VA), central retinal thickness (CRT), arterial (aO2S), venous (vO2S) and arterio-venous difference (AVdO2S) retinal oxygen saturation were noted monthly. Changes after 5th (V6) injection and on last follow-up (V12) were studied. Correlations of different parameters were analyzed. RESULTS: The aO2S did not change whereas vO2S decreased (62.2 ± 9.4 pre-op to 57.2 ± 10.5 on V6, p = 0.03). This remained unchanged at 59.4 ± 13.2 on V12 (p = 0.2) and was accompanied by an increase of AVdO2S (40.8 ± 8.3 pre-op to 44.8 ± 10.6, p = 0.03 on V6) which was followed by a non-significant decrease to 41.8 ± 11.3 on V12 (p = 0.06). We found no correlation between BCVA and aO2S. However, mild correlation between BCVA and both vO2S and AVdO2S (r = -0.2 p = 0.035 and r = 0.185 p = 0.05 respectively) was found. No correlation was found between CRT and aO2S, vO2S, or AVdO2S. CONCLUSIONS: During DME treatment with fixed regimen of intravitreal aflibercept over 11 months, we observed a reduction of vO2S and increase of AVdO2S which correlated with BCVA but not CRT. This could be explained by increasing consumption of O2S in the central retina and, possibly, by re-perfusion process.

Partial descemetorhexis for delayed Descemet membrane detachment following penetrating keratoplasty, suggestion of a pathomechanism.

PURPOSE: to report a case of delayed Descemet membrane detachment (DMD) 45 years after penetrating keratoplasty (PK) for keratoconus and its management with a partial descemetorhexis after failed air/gas descemetopexy. A pathomechanism of DMD is proposed based on the anatomic appearance of the DMD and the success of descemetorhexis. OBSERVATIONS: a 60-year old male presented with acute corneal edema of his left eye 45 years after successful PK for keratoconus. Anterior segment ocular coherence tomography (AS-OCT) revealed a wide area of DMD without a visible tear. Reattachment was tried using air and gas descemetopexy with only temporary success. A partial descemetorhexis was then performed just centrally to the graft-host interface and only in the detached area followed by injection of gas bubble. Complete reattachment of Descemet membrane (DM) on the 1st post-operative day was achieved. This anatomical success was maintained 3 months post-surgery and accompanied by decrease of central corneal thickness, however with uncomplete restoration of visual acuity. CONCLUSION: delayed DMD following KP for keratoconus should be differentiated from acute graft rejection. It could be a result of Descemet tear, but in some cases and despite careful observation of AS-OCT no tear could be seen. In such cases, a tractional detachment of DM might be the underlying pathomechanism and descemetorhexis could help manage it. This new surgical approach might help avoid a re-keratoplasty. IMPORTANCE: This is the first case report describing success of partial descemetorhexis as a surgical management option for delayed DMD and suggesting a pathogenesis based on this success. This might help avoid re-keratoplasty as a management of this rare complication.

Correlation of the Retinal Parapapillary Perfusion and the Retinal Vessel Oxygen Saturation in Glaucoma Patients.

Purpose: Reduced perfusion of the retinal parapapillary tissue is well documented in glaucoma patients. Whether or not this is a cause or result of the disease is however unknown. Studying the correlation of this perfusion and the retinal vascular oxygen saturation (O2S) could give clues to the retinal O2 consumption/demand and provide an answer to this question. Methods: Seventeen eyes of 17 healthy controls and 32 eyes of 32 patients with primary open angle glaucoma were prospectively recruited. Global and sectoral nerve fiber layer (NFL) thickness was measured with optical coherence tomography (OCT); parapapillary OCT-angiography was performed and quantified into vascular density (VD) and perfusion density (PD). Retinal vascular O2S was measured. Results: Global and sectoral NFL thickness, VD, PD (except for temporal sector of VD), and arteriovenous difference of O2S (AV-D) were lower in glaucomatous eyes compared with controls (P < 0.05 for all). A significant inverse correlation of venous O2S with global VD (r = -0.37, P = 0.04) and PD (r = -0.37, P = 0.04) and a direct correlation of the AV-D with global VD (r = 0.50, P = 0.004) and PD (r = 0.49, P = 0.004) were observed. In sector analysis, the strongest correlation of AV-D with VD and PD was seen in inferior (VD: r = 0.52, P = 0.001; PD: r = 0.55, P = 0.002) and superior (VD: r = 0.454, P = 0.009; PD: r = 0.46, P = 0.008) segments. Conclusions: In glaucomatous eyes, there exists a direct correlation of the AV-D to the VD and PD with the strongest correlation being in superior and inferior segments where typically tissue loss occurs. This could possibly be explained by the loss of tissue being followed by the reduced density.

Coat's like vasculopathy in leber congenital amaurosis secondary to homozygous mutations in CRB1: a case report and discussion of the management options.

BACKGROUND: Mutations in the CRB1 gene are associated with variable phenotypes of severe retinal dystrophies, and retinal dystrophies resulting from CRB1 mutations may be accompanied by specific fundus features such as coat's like vasculopathy in retinitis pigmentosa patients. This is the first report of the occurrence of coat's like vasculopathy in a patient diagnosed with Leber congenital amaurosis caused by a CRB1 mutation. CASE PRESENTATION: An 18-year old Syrian female patient presented with bilateral gradual loss of vision since early childhood, with recent deterioration in her left eye. She appeared to have an asymmetric bilateral coat's like vasculopathy which was more severe in the left eye. The diagnosis of Leber congenital amaurosis was suggested, and a genetic CRB1 sequencing for the patient and her two younger siblings, who also had severe vision loss, was done, upon which the diagnosis of Leber congenital amaurosis associated with exudative retinal detachment due to coat's like vasculopathy was made. Treatment with panretinal photocoagulation was attempted in the worse left eye, but with no improvement. As the disease suddenly progressed in both eyes, pars plana vitrectomy with endolaser and silicone oil tamponade was performed in the better right eye which led to anatomical stabilization of the case without improvement in the visual acuity. CONCLUSION: Leber congenital amaurosis is reported to be associated with multiple systemic and ocular findings, none of which is coat's like vasculopathy. CRB1 gene mutations are associated with remarkable retinal findings in patients with retinitis pigmentosa and other fundus dystrophies. In this unique case we are reporting the incidence of coat's like vasculopathy in a patient diagnosed with Leber congenital amaurosis caused by CRB1 gene mutation, and its management. CRB1 mutant patients should be followed up closely as sudden progression can have permanent poor outcomes and as early management is vital in such cases.