Intraoperative challenges and management of fibrovascular membrane with tractional retinoschisis in proliferative diabetic retinopathy.

BACKGROUND: In severe Proliferative Diabetic Retinopathy (PDR), fibrovascular membrane (FVM) causes macular tractional retinal detachment (MTRD) which threatens vision and eventually leads to blindness. Here we present a case of separation between the inner and outer retina in tractional retinoschisis, induced during intraoperative FVM delamination. CASE PRESENTATION: A 68-year-old woman presented with PDR in the right eye, characterized by a combined FVM and retinal detachment, for which a vitrectomy was performed. Multiple holes, large retinal detachment extending to all quadrants, and white-lined blood vessels with FVM were found during the procedure. When membrane delamination was performed, it strayed into the space between the inner and outer retinal layers without being noticed due to retinoschisis and multiple retinal holes. After removing the FVM and detaching the separated inner retina, fluid-gas and photocoagulation were performed. Retinal reattachment was successfully achieved after surgery, and the postoperative visual acuity was improved and maintained for 26 months postoperatively. CONCLUSIONS: When tractional retinoschisis due to FVM is combined with retinal holes in tractional retinal detachment (TRD), care must be taken to prevent delamination from straying into retinoschisis during separation.

Real-time corneal thickness changes during phacoemulsification cataract surgery.

PURPOSE: To observe the changes in corneal thickness during phacoemulsification cataract surgery and to analyze the influencing factors. METHODS: One hundred two patients (102 eyes) with cataracts undergoing phacoemulsification cataract surgery at Shandong Eye Hospital between July and October 2021 were included. Intraoperative OCT was applied to capture real-time images preoperatively, before and after ultrasonic emulsification, at the end of irrigation aspiration and the end of surgery. Then, the corneal thickness at the above time points was measured using Photoshop software. RESULTS: The corneal thickness of 102 cataract patients was 511.79 ± 31.46 µm before operation and 512.71 ± 31.51 µm at the beginning of phacoemulsification, which increased by 0.91 ± 1.48 µm (0.2%). At the end of ultrasonic emulsification, the corneal thickness was 521.58 ± 32.75 µm and 8.87 ± 8.71 µm (1.7%) thicker than that before the procedure. After irrigation aspiration, the corneal thickness reached 528.09 ± 33.87 µm, which increased by 6.52 ± 6.38 µm (1.3%) compared with that of the previous step. At the end of the operation, the corneal thickness was 539.19 ± 33.88 µm, 11.09 ± 10.92 µm, and 27.37 ± 13.64 µm thicker than that of the previous step and the preoperative thickness, respectively, with an overall increase of 5.3%. The differences were statistically significant at all time points (all P < 0.001). Correlation analysis showed that postoperative corneal thickness changes were correlated with age, cataract lens nuclear grade, actual phacoemulsification time (APT), effective phacoemulsification time (EPT), average phacoemulsification energy (APE), total surgery time (TST), cell density (CD), maximum cell area (MAX), and cell area standard deviation (SD) (all P < 0.05), while the changes in thickness were not correlated with gender, cell area coefficient of variation (CV), percentage of hexagonal cells (6A), average cell area (AVE), or minimum cell area (MIN) (all P > 0.05). CONCLUSIONS: During phacoemulsification cataract surgery, corneal thickness gradually increases in real time with the increase of perfusion pressure and intraocular manipulation time. The real-time magnitude of intraoperative corneal thickness change is closely related to lens nucleus hardness, corneal endothelial cell density, ultrasound energy, and time for emulsification.

[Intraoperative optical coherence tomography in vitreoretinal surgery]. / Intraoperatsionnaya opticheskaya kogerentnaya tomografiya v vitreoretinal'noi khirurgii.

This article reviews literature on the use of intraoperative optical coherence tomography (iOCT) in vitreoretinal surgery, describes the historical aspects of the development of this technology from portable devices to optical coherence tomographs integrated into the surgical microscope, considers the advantages, limitations and disadvantages of this technology, which are now becoming obvious due to the accumulated experience. The review also explores the prospects for the development of iOCT and possible ways to solve its problems. In addition, the review presents and systematizes clinical findings that can be revealed with iOCT in such diseases as rhegmatogenous retinal detachment, complications of proliferative diabetic retinopathy, macular pathology, etc.

Intraoperative optical coherence tomography guided corneal sweeping for removal of remnant Interface fluid during ultra-thin Descemet stripping automated endothelial keratoplasty.

BACKGROUND: Remnant interface fluid following Descemet stripping automated endothelial keratoplasty (DSAEK) is associated with postoperative detachments. The aim of this study was to assess outcomes of intraoperative optical coherence tomography (iOCT) guided meticulous peripheral corneal sweeping for removal of interface fluid during ultra-thin (UT) DSAEK. METHODS: This retrospective study included all eyes underwent iOCT guided UT-DSAEK from October 2016 to February 2018 at the Hanusch Hospital, Vienna, Austria. Peripheral meticulous corneal sweeping was performed to remove excess fluid. Central graft thickness (CGT) was measured prior to surgery, after graft bubbling and after corneal sweeping. Remnant interface fluid rates were compared between eyes that underwent rebubbling and those that did not. RESULTS: Overall, 28 eyes of 28 patients with a mean age of 73.9 ± 10.0 years were included. An iOCT guided meticulous peripheral sweeping was performed in 89.3% (n = 25) of the cases. Following 84% (n = 21) of the peripheral sweeping performed, remnant fluid was no longer identified. Following peripheral sweeping the interface fluid height was reduced from 17.31 ± 15.96 µm to 3.46 ± 9.52 µm (p < 0.001) and CGT was reduced by 7% (p < 0.001). Rebubbling was performed in 17.9% (n = 5) of the cases. The rebubbling group had a greater proportion of patients that had remnant fluid identified with iOCT at the end of surgery despite meticulous peripheral sweeping (60.0% versus 4.4%, p = 0.01). CONCLUSION: The iOCT identified subclinical remnant fluid in nearly 90% of UT-DSAEK cases. An iOCT guided peripheral corneal sweeping led to resolution of interface fluid in a majority of cases. Eyes with persistent remnant fluid despite peripheral corneal sweeping are more likely to require subsequent rebubbling.

Effect of Iatrogenic Traction during Macular Peeling Surgery on Postoperative Microperimetry.

INTRODUCTION: Vitrectomy with peeling of epiretinal membrane (ERM) and internal limiting membrane offers the chance for improvement of metamorphopsia and visual acuity. Microscope integrated intraoperative optical coherence tomography (iOCT) enables real-time imaging of retinal alterations during peeling, such as intraoperative transient retinal thickening owing to tractional forces during peeling. The aim of our study was to measure the amounts of transient retinal thickening due to tractional forces during membrane peeling, as documented with iOCT, and to analyze possible effects on postoperative retinal function. METHODS: This prospective, monocenter study included patients scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic ERM. During peeling, an iOCT device (ReScan700, Carl Zeiss Meditec AG) with continuous OCT-assistance during the peeling procedure, and video documentation of the peeling procedure, was used for the assessment of intraoperative transient retinal thickening owing to tractional forces during peeling. Directly before and 3 months after surgery, macular-OCT scans and microperimetry were performed. RESULTS: Twenty-five eyes of 25 patients were included in the study. Microperimetry could be performed in all patients, while iOCT documentation could be analyzed in 22 patients. Transient retinal thickening owing to tractional forces during peeling could be observed in 14 patients (64%), with a median thickening to 143% of the normal (preoperative) retinal thickness at that location (IQR 132-163). Six patients (24%) developed new deep microscotomata as seen in microperimetry 3 months after surgery, among them were 2 patients who also had transient retinal thickening during peeling. CONCLUSION: New deep microscotomata developed only in a minority of patients with transient retinal thickening owing to tractional forces during peeling.

One-Year Anatomical and Functional Outcomes of the Argus II Implantation in Korean Patients with Late-Stage Retinitis Pigmentosa: A Prospective Case Series Study.

PURPOSE: To report the anatomical and functional outcomes of Argus II retinal prosthesis implantation in Korean patients. METHODS: We included 5 consecutive patients with end-stage retinitis pigmentosa (RP) who underwent Argus II retinal prosthesis implantation and were followed for at least 12 months. The transcorneal electrical evoked response was utilized for patient selection. We used intraoperative optical coherence tomography (OCT) for optimal placement of the array and provided specialized vision rehabilitation training. A morphological evaluation using SD-OCT and a functional evaluation using computer-based visual function tests, a letter-reading ability test, and the Functional Low-Vision Observer Rated Assessment (FLORA) were conducted. RESULTS: Postoperatively, the array was completely apposed to the retinal surface in all eyes, except for one eye which had a preexisting macular concavity. Fibrosis-like tissues of ≥50-µm thickness developed at the interface in 2 eyes. All of the patients showed improvement in computer-based visual function tests and could read ETDRS letters at a distance of 50 cm. Three patients could read Korean words. FLORA was improved in all patients, mainly in tasks of visual mobility, daily activities, and social interactions. CONCLUSIONS: Along with good anatomical outcomes and specialized rehabilitation practices, recipients of the Argus II implant showed profound improvements in functional vision and mobility.

Macular hole edge morphology predicts restoration of postoperative retinal microstructure and functional outcome.

BACKGROUND: To investigate the ability of intraoperative optical coherence tomography (iOCT) during macular hole (MH) surgery to image different hole edge configurations and predict the restoration of retinal microstructure and visual outcomes. METHODS: This retrospective case series study included 53 MH patients. One eye each was assessed with iOCT during vitrectomy after internal limiting membrane (ILM) peeling. The MHs were categorized into three groups according to the morphology of the hole edge. The Hole-Door group had vertical pillars of tissue that projected into the vitreous cavity after ILM peeling. The Foveal Flap group had a preoperative foveal flap that adhered to the hole edge after ILM peeling, and the Negative group had neither a hole-door nor a foveal flap. At 6 months after surgery, the retinal microstructure restoration and visual outcomes were compared among the groups. RESULTS: All eyes had MH closure, and the postoperative best corrected visual acuity (BCVA) was significantly improved compared with the preoperative BCVA (P < 0.001). The Hole-Door group (n = 15) and Foveal Flap group (n = 14) had significantly better final visual acuity and postoperative restoration of the external limiting membrane (ELM) than the Negative group (n = 24) (P = 0.002, P = 0.012). For the group in which the MH diameter (MHD) was ≤400 µm (n = 25), there were no significant differences in ELM restoration, ellipsoid zone (EZ) restoration, or BCVA among the three groups (P = 0.516, P = 0.179, and P = 0.179 respectively). For the MHD > 400-µm group (n = 28, the Hole-Door group and Foveal Flap group had significantly better final visual acuity and restoration of ELM than the Negative group (P = 0.013, P = 0.005). CONCLUSIONS: The novel use of iOCT during MH surgery confirmed the presence of hole edges configured as door-holes, foveal flaps, or neither. The data acquired by iOCT can provide useful predictive information for postoperative restoration of the retinal microstructure and visual outcome of MH, especially large ones.

Feasibility and Safety of Intraoperative Optical Coherence Tomography-Guided Short-Term Posturing Prescription after Macular Hole Surgery.

PURPOSE: To assess closure rate and visual outcome of a court of patients with macular hole (MH) who underwent surgical repair with intraoperative optical coherence tomography (iOCT)-confirmed MH closure and short-term postoperative face-down posturing (FDP). Secondary aim was to assess the correlation between iOCT and postoperative OCT at day 1. METHODS: Retrospective clinical study conducted in the Miulli Hospital Acquaviva delle Fonti (Italy), enrolling patients with idiopathic MH who underwent 25-G pars plana vitrectomy plus internal limiting membrane peeling. During surgery, closure of MH was confirmed by iOCT and short-term FDP (12-24 h, until day-1 visit) was prescribed. All patients had measurement of best-corrected visual acuity (BCVA) and spectral domain-OCT before the surgery and during follow-up (at 1 day, 1 month, 3 months). RESULTS: Twenty-nine eyes of 29 patients (14 males, 62.1%) were enrolled in the study. MH mean size was 451.7 ± 139.7 µm and baseline BCVA was 0.77 ± 0.26 logarithm of the minimum angle of resolution (LogMAR). MH was confirmed to be closed in 100% of patients intraoperatively (iOCT) and at OCT during early follow-up (1-3 days). Mean time of FDP was 18 ± 2.6 h. At 3 months, MH closure rate was 93%; 2 eyes -underwent secondary MH repair surgery. Final BCVA was 0.39 ± 0.22 LogMAR (p < 0.0001). CONCLUSION: iOCT-based confirmation of MH closure could be a safe and useful tool for prescribing short-term FDP after surgery, with high closure rate and no additional complication. The execution of an OCT in the immediate postoperative days could be potentially unnecessary.

Effect of Subfoveal and Extrafoveal Hyporeflective Zones due to Iatrogenic Traction during Membrane Peeling for Epiretinal Membranes on Postoperative Outcomes.

PURPOSE: The aim of our study using an intraoperative optical coherence tomography (iOCT) device was to assess the rate of neurosensory elevation with resulting subfoveal and extrafoveal hyporeflective zones during membrane peeling and to evaluate a possible influence on postoperative outcomes. PROCEDURES: This study included patients scheduled for pars plana vitrectomy with membrane peeling due to idiopathic epiretinal membrane. All patients underwent 23-G pars plana vitrectomy with iOCT-guided membrane peeling and were scheduled for follow-up examinations at 1 day, 5 days, and 3 months after surgery. RESULTS: Among the 171 patients included, subfoveal and extrafoveal hyporeflective zones could be detected in 12 patients (7%). Follow-up at 3 months after surgery was available for 149 patients with a median improvement in best corrected visual acuity of +2 lines (IQR: +1 to +4 lines). There were no significant differences in outcomes between patients with and those without subfoveal/extrafoveal hyporeflective zones concerning visual acuity, macular thickness, occurrence of intraretinal cystoid changes, and postoperative hyporeflective zones. CONCLUSIONS: No significant differences in postoperative outcomes were observed between patients with and those without subfoveal/extrafoveal hyporeflective zones.

Intraoperative Optical Coherence Tomography-Guided Membrane Peeling for Surgery of Macular Pucker: Advantages and Limitations.

PURPOSE: Epiretinal membranes (ERMs) are a disorder leading to progressive vision loss and metamorphopsia. The gold standard in therapy is vitrectomy with membrane peeling. The aim of this study was to assess whether the use of intraoperative optical coherence tomography (iOCT), which allows tomographic visualization of the membrane during peeling, enables peeling without staining. METHODS: This prospective study included 30 eyes of 30 patients with idiopathic ERMs scheduled for surgery. Pars plana vitrectomy with iOCT was performed in all cases, whereas staining of ERMs was only performed if needed. Internal limiting membrane (ILM) peeling was performed in case of wrinkled retinal surface after peeling of ERMs. RESULTS: In 63% (n = 19) eyes the ERM could be peeled successfully without use of staining. Nevertheless, in 89% (n = 17) of patients having had ERM peeling without dye, staining of the ILM was performed afterwards for peeling the ILM. Best corrected visual acuity improved in 80% (n = 24) and remained unchanged in 7% (n = 2) 3 months after surgery. There were no significant differences in postoperative results between patients with and without staining for ERM peeling. CONCLUSIONS: Use of iOCT helps to complete ERM peeling in a majority of cases without use of a chromovitrectomy dye, but as iOCT fails to visualize the ILM, chromovitrectomy still facilitates macular surgery in a majority of cases.

Alterations of Foveal Architecture during Vitrectomy for Myopic Retinoschisis Identified by Intraoperative Optical Coherence Tomography.

PURPOSE: To determine the changes in the foveal architecture before and after internal limiting membrane (ILM) peeling with and without fovea-sparing ILM peeling (FSIP) during vitrectomy for high myopic retinoschisis by intraoperative optical coherence tomography (iOCT). METHODS: Qualitative assessments were made of the alterations of the retinal architecture imaged by iOCT following complete ILM peeling (peeled group) or fovea-sparing ILM peeling (FSIP group). A microscope-integrated real-time iOCT device was used to analyze the retinal architectures. The alterations included a worsening of the retinoschisis, development of a foveal detachment, and development of a full thickness macular hole. The changes in the retinal architecture, clinical characteristics, and outcomes were compared between the 2 groups. RESULTS: The medical records of 15 eyes of 15 patients were studied. Complete ILM peeling was performed on 9 of 15 eyes, and 8 of the 9 eyes (89%) showed a worsening of the retinal architectures following the ILM peeling. FSIP was performed on 6 of the 15 eyes, and none of these eyes developed any retinal architectural changes in the iOCT images. The mean postoperative best-corrected visual acuity (BCVA) in eyes that underwent FSIP (20/38) was significantly better than that of preoperative BCVA (20/128; p < 0.05), although the differences in the preoperative BCVA (20/87) and postoperative BCVA (20/55) in the cases that underwent complete ILM peeling were not significant. CONCLUSIONS: The lack of alterations of the foveal architecture and significant improvements in the BCVA after FSIP indicate that FSIP peeling should be considered for eyes with retinoschisis. We recommend that iOCT be used to monitor the retinal architecture during intraocular surgery involving the retina.

Intraoperative changes in corneal structure during excimer laser phototherapeutic keratectomy (PTK) assessed by intraoperative optical coherence tomography.

PURPOSE: Excimer laser phototherapeutic keratectomy (PTK) is a safe treatment for superficial corneal opacities, e.g., in corneal dystrophies or degenerations. Nevertheless, no standardized treatment protocols are available and intraoperative monitoring was not possible, so far. Here we evaluate the potential benefits of the intraoperative assessment by microscope-integrated intraoperative optical coherence tomography (MI-OCT) of corneal optical properties during PTK. METHODS: Retrospective study of eight patients (one male, seven females; age range, 43-80 years, mean = 66.1 years) using an 840-nm microscope-integrated spectral-domain OCT (iOCT; OptoMedical Technologies, Luebeck, Germany adapted to HS Hi-R Neo 900A, Haag Streit Surgical, Wedel, Germany). Images were acquired before and after corneal abrasion and after PTK. For PTK, a SCHWIND Amaris 750S excimer laser (SCHWIND eye-tech-solutions GmbH und KO. KG) was used. Parameters assessed were the central corneal thickness (CCT), changes in central depth-dependent corneal tissue intensity (TI), and corneal surface roughness (SR) in cross-sectional images of the cornea. RESULTS: Intraoperative monitoring using microscope-integrated OCT was possible in all patients at all time points. TI of the anterior corneal stroma decreased significantly (p = 0.037) after PTK (T1 = 15.1 ± 3.6, T2 = 15.0 ± 3.84, T3 = 13.7 ± 3.38), but not after corneal abrasion alone, indicating increased transparency caused by excimer laser PTK. CCT was significantly lower after corneal abrasion (p = 0.017), but not after PTK (T1 = 630.4 ± 70 µm, T2 = 544.1 ± 59.4 µm, T3 = 558.3 ± 52.5 µm. SR significantly decreased (p = 0.043) after PTK (T1 = 614.4 ± 37.5 pixels, T2 = 634.4 ± 35.6 pixels, T3 = 611.0 ± 40.3 pixels). CONCLUSIONS: Intraoperative OCT allows real-time imaging during PTK and the assessment of corneal optical transparency and its surface roughness. It has to be clarified in larger studies if these parameters correlate with later postoperative visual outcomes.

Outcomes of microscope-integrated intraoperative optical coherence tomography-guided center-sparing internal limiting membrane peeling for myopic traction maculopathy: a novel technique.

PURPOSE: To evaluate the outcomes of pars plana vitrectomy (PPV) with microscope-integrated intraoperative optical coherence tomography (I-OCT)-guided traction removal and center-sparing internal limiting membrane (cs-ILM) peeling. METHODS: Nine eyes with myopic traction maculopathy as diagnosed on SD-OCT underwent PPV with I-OCT-guided cs-ILM peeling and were evaluated prospectively for resolution of central macular thickness (CMT) and improvement in best-corrected visual acuity (BCVA), and complications, if any, were noted. All patients were followed up for more than 9 months. RESULTS: Resolution of the macular retinoschisis was seen in all nine eyes on SD-OCT. At 36 weeks, there was a significant improvement in mean BCVA from the preoperative BCVA (P = 0.0089) along with a reduction in the CMT from 569.77 ± 263.19 to 166.0 ± 43.91 um (P = 0.0039). None of the eyes showed worsening of BCVA or development of full-thickness macular hole in the intraoperative or follow-up period. CONCLUSION: PPV with I-OCT-guided cs-ILM peeling helps in complete removal of traction, resolution of retinoschisis and good functional recovery with low intraoperative and postoperative complications.

Intraoperative optical coherence tomography (RESCAN® 700) for detecting iris incarceration and iridocorneal adhesion during keratoplasty.

There is no report focusing on the visualization of the iris incarceration or the iridocorneal adhesion during keratoplasty by use of microscope-integrated intraoperative optical coherence tomography (MIOCT). The purpose of this study is to report the usefulness of MIOCT for detecting iris incarceration and iridocorneal adhesions during penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK). MIOCT system was applied both in a patient who underwent PK for corneal leukoma and in a patient who underwent DALK for keratoconus. During the surgeries, we obtained cross-sectional images around the host-graft interface by operating the foot switch of microscope without discontinuing the surgical procedure. Intraoperative MIOCT findings and postoperative outcomes were examined. An iris incarceration at the host-graft interface was visualized during surgery after corneal suture in PK, which allowed surgeons to return the iris to its original position instantly. In DALK, misdirected air into the posterior chamber could also be seen at the end of the DALK. This iridocorneal adhesion was resolved by fluid injection through paracentesis. Secondary glaucoma and graft rejection have not occurred postoperatively in both cases. The MIOCT system provides advantages such as prevention of secondary glaucoma and rejection following PK and DALK.

Intraoperative optical coherence tomography in descemet stripping automated endothelial keratoplasty: pilot experiences.

PURPOSE: To assess the added value of intraoperative optical coherence tomography (iOCT) in evaluating graft adhesion and graft interface in patients undergoing descemet's stripping automated endothelial keratoplasty (DSAEK). METHODS: This is a prospective single-center case series comprising 8 eyes of 8 patients consecutively scheduled for DSAEK surgery. iOCT imaging was performed after insertion of the graft, after pressurizing the eye, and at the end of surgery (three images per surgery). At each stage of surgery, corneal thickness and the widest gap between the recipient and the graft (i.e., maximal interface width) were measured using an image processing tool. Follow-up measurements were taken at 1 day, 3 and 6 months, post-operatively. RESULTS: Imaging was performed in 21 of 24 scheduled imaging intervals, and required little to no additional surgical time. At the end of surgery, iOCT showed persisting interfaces in six cases. One case showed a full graft detachment necessitating surgical intervention. CONCLUSION: Real-time iOCT is a safe, efficient, and useful tool in assessing graft adherence in DSAEK surgery. With adequate analysis software, iOCT has the potential to be a paradigm-shifting development in posterior lamellar surgery and could aid the clinician in further lowering the rates of graft dislocation after DSAEK.

Intraoperative optical coherence tomography-guided deep anterior lamellar keratoplasty.

Gauging stromal dissection depth is crucial to successfully perform deep anterior lamellar keratoplasty (DALK) surgery. Intraoperative optical coherence tomography (iOCT) offers a promising tool to aid DALK surgery but visualization of surgical maneuvers is impaired due to artifacts from metallic instruments. We describe a novel surgical technique utilizing suture-assisted iOCT guidance that facilitates clear visualization of corneal dissection planes during DALK. A stromal dissection tunnel is performed with a Fogla probe and its depth is subsequently identified by threading a 1 cm segment of 8-0 nylon into the tunnel. In contrast to the Fogla probe, the 8-0 nylon is conspicuously highlighted on iOCT. If the tunnel is too superficial, a separate, deeper stromal tunnel can be created and visualized again with the 8-0 nylon suture and iOCT. This iterative process facilitates a deep stromal dissection, increasing the probability of successful big-bubble formation and Descemet baring DALK surgery. This technique was utilized for a successful big-bubble DALK in a patient with severe keratoconus.

Microstructural morphology and visual acuity outcome in eyes with epiretinal membrane before, during, and after membrane peeling in intraoperative optical coherence tomography assisted macular surgery.

AIM: To measure the difference of intraoperative central macular thickness (CMT) before, during, and after membrane peeling and investigate the influence of intraoperative macular stretching on postoperative best corrected visual acuity (BCVA) outcome and postoperative CMT development. METHODS: A total of 59 eyes of 59 patients who underwent vitreoretinal surgery for epiretinal membrane was analyzed. Videos with intraoperative optical coherence tomography (OCT) were recorded. Difference of intraoperative CMT before, during, and after peeling was measured. Pre- and postoperatively obtained BCVA and spectral-domain OCT images were analyzed. RESULTS: Mean age of the patients was 70±8.13y (range 46-86y). Mean baseline BCVA was 0.49±0.27 logMAR (range 0.1-1.3). Three and six months postoperatively the mean BCVA was 0.36±0.25 (P=0.01 vs baseline) and 0.38±0.35 (P=0.08 vs baseline) logMAR respectively. Mean stretch of the macula during surgery was 29% from baseline (range 2%-159%). Intraoperative findings of macular stretching did not correlate with visual acuity outcome within 6mo after surgery (r=-0.06, P=0.72). However, extent of macular stretching during surgery significantly correlated with less reduction of CMT at the fovea centralis (r=-0.43, P<0.01) and 1 mm nasal and temporal from the fovea (r=-0.37, P=0.02 and r=-0.50, P<0.01 respectively) 3mo postoperatively. CONCLUSION: The extent of retinal stretching during membrane peeling may predict the development of postoperative central retinal thickness, though there is no correlation with visual acuity development within the first 6mo postoperatively.

Clinical and diagnostic imaging profile of three anterior segment dysgenesis disorders presenting with infantile corneal opacities.

PURPOSE: To describe three anterior segment dysgenesis disorders with infantile corneal opacities, namely, congenital hereditary endothelial dystrophy (CHED), primary congenital glaucoma (PCG), and Peters anomaly (PA) in terms of clinical characteristics, histopathology, genetic association, and diagnostic imaging profiles using imaging modalities such as ultrasound biomicroscopy (UBM) and microscope-integrated intraoperative optical coherence tomography (i-OCT). MATERIALS AND METHODS: Seventy-four eyes with 22 eyes of CHED, 28 eyes of PA, and 24 eyes of PCG were clinically evaluated and underwent imaging using UBM and i-OCT. Corneal buttons of 16 operated patients underwent histopathological analysis, while genetic analysis was done in 23 patients using whole-exome sequencing. RESULTS: Corneal diameters (CD) and UBM parameters like anterior chamber depth (ACD), iris thickness (IT), and ciliary body (CB) thickness revealed a statistically significant difference between the three categories. In PA, 9 eyes had a third rare phenotype with only a posterior corneal defect with no iris adhesions. Genetic mutations were seen in all tested patients with CHED, in 83.3% of patients with PCG, and in 80% of patients with the third type of PA. i-OCT helped in the characterization of corneal opacity, identification of posterior corneal defects, iridocorneal adhesions, and contour of Descemet's membrane. CONCLUSION: Overlapping phenotypes of the above disorders cause a diagnostic dilemma and parameters like CDs, UBM ACD, IT, and CB thickness help differentiate between them. i-OCT can help in classifying the diseases in a high resolution, non-contact manner, and can better delineate corneal characteristics. The rare third type of PA phenotype may have a genetic association.

Intraoperative Optical Coherence Tomography in Idiopathic Macular Epiretinal Membrane Surgery.

Objective: To evaluate the feasibility and practicability of intraoperative optical coherence tomography (IOCT) in the surgery of idiopathic macular epiretinal membrane (IMM) without internal limiting membrane staining in all patients. Methods: Patients were selected from July 2018 to June 2020, and 32 patients (32 eyes) with IMM were operated with the use of IOCT. All patients underwent standard 23g vitrectomy. The internal limiting membrane was peeled off if there were obvious retinal folds. Intraoperative and postoperative complications, macular microstructural changes, and integrity of the detached membranes were recorded. The preoperative and postoperative best corrected visual acuity were compared. Results: The macular epiretinal membrane was completely removed in 75% (24 eyes) patients without internal limiting membrane staining, and in 15.6% (5 eyes) patients with combined internal limiting membrane stripping. The "starting point" of macular epiretinal membrane stripping was found in 75% (24 eyes), and the time required to find the best starting point ranged from 28s to 140s (mean 66 ± 15s). At 3 months after operation, 96.8% of the patients had stable or improved BCVA (p < 0.05). The central macular thickness of the affected eyes decreased significantly at 1 and 3 months after operation (p < 0.05). Conclusion: IOCT can significantly reduce the use of internal limiting membrane staining in idiopathic macular epiretinal membrane surgery, and it is safe, feasible and practical in idiopathic macular epiretinal membrane surgery without internal limiting membrane staining in all patients.

Integrated Intraoperative Optical Coherence Tomography during Scleral Pass in Strabismus Surgery.

We describe a novel application of integrated intraoperative OCT (iiOCT) to strabismus surgery during the scleral pass and demonstrate it to be a useful tool. A number of complications can arise from inappropriate scleral pass depth during strabismus surgery, leading to an increased risk of unwanted complications including endophthalmitis, retinal detachment, and a lost or slipped muscle. Our study demonstrated that the use of iiOCT provides easy to interpret, real-time feedback to the strabismus surgeon and may translate to safer, more consistent scleral suturing during strabismus surgery and strabismus surgical training. .