PURPOSE: To investigate structure-function associations between contrast sensitivity (CS) and widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vascular metrics across stages of non-proliferative (NPDR) and proliferative diabetic retinopathy (PDR), without diabetic macular oedema. METHODS: Prospective cross-sectional study in 140 eyes of 99 patients: 33 mild NPDR, 24 moderate/severe NPDR, 15 PDR, 33 diabetic without DR (DMnoDR) and 46 control eyes. Mixed-effects multivariable regression models to evaluate associations between quantitative contrast sensitivity function (Adaptive Sensory Technology) and vessel density (VD) and vessel skeletonised density (VSD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) on same-day imaging with WF SS-OCTA (Plex Elite 9000, Carl Zeiss Meditec). RESULTS: Standardised ß coefficients for area under the logarithm of contrast sensitivity function curve (AULCSF) versus visual acuity (VA) at 3×3 mm scans: SCP VSD (ß=0.32, p<0.001 vs -0.18, p=0.044), DCP VSD (ß=0.30, p<0.001 vs -0.21, p=0.02), SCP VD (ß=0.25, p=0.004 vs -0.13, p=0.129), DCP VD (ß=0.26, p=0.003 vs -0.19, p=0.034). AULCSF was significantly reduced in mild NPDR (ß=-0.28, p<0.001) and DMnoDR (ß=-0.19, p=0.005) versus controls, while VA was not significantly different. AULCSF performed better than VA in differentiating between controls and DMnoDR (0.69 vs 0.50), controls and mild NPDR (0.76 vs 0.61) and controls and moderate/severe NPDR (0.89 vs 0.73). CONCLUSIONS: DR-induced microvascular changes on OCTA are associated with larger changes on CS than in VA. CS is affected earlier than VA in the course of DR and performed better in discriminating between controls, DMnoDR and across DR stages.
BACKGROUND AND OBJECTIVE: Our objective was to assess baseline widefield swept-source optical coherence tomography angiography (WF SSOCTA) microvascular metrics as predictors for the number of anti-vascular endothelial growth factor (VEGF) injections and visual acuity (VA) at 12-months follow-up in patients with retinal vein occlusion (RVO). PATIENTS AND METHODS: This was a prospective study including 49 RVO eyes from 49 patients who had not received an anti-VEGF injection for at least 3 months prior to imaging. Microvascular metrics from 6×6-mm and 12×12-mm angiograms were assessed using linear regression models, adjusting for age. RESULTS: Reductions in the vessel density (VD) and vessel skeletonized density (VSD) vascular metrics were associated both with a higher number of anti-VEGF injections at all follow-up time points and reduced VA 12 months after imaging in all RVO eyes. CONCLUSIONS: WF SS-OCTA VD and VSD micro-vascular metrics at baseline can prognosticate VA and number of anti-VEGF injections required at 3, 6, and 12 months in RVO eyes. [Ophthalmic Surg Lasers Imaging Retina 2024;55:xx-xx.].
PURPOSE: To investigate the impact of anti-VEGF therapy on vascular metrics in eyes with macular edema secondary to central retinal vein occlusion (CRVO) using wider field swept-source OCT angiography (WF SS-OCTA). METHODS: We included 23 eyes with macular edema associated with non-ischemic CRVO from 22 patients treated with anti-VEGF therapy (median number of injections: 5 [2-9]). Changes in vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ) parameters were measured using WF SS-OCTA. Visual acuity (VA) and central subfield thickness (CST) were also measured. RESULTS: Median CST decreased significantly from 369 µm (305-531) to 267 µm (243-300, p < 0.001). VD and VSD parameters in 12 × 12 mm images showed significant reductions. For instance, VSD in the whole retina decreased from a median of 13.37 (11.22-13.74) to 11.29 (9.36-12.97, p = 0.013). Additionally, a significant increase in FAZ circularity was found, suggesting improved microvascular integrity. Significant inverse correlations were found between the number of anti-VEGF injections and all VSD and VD parameters on the 12 × 12 mm images (p < 0.05). Notably, the reductions in VSD and VD on 12 × 12 mm angiograms in the deep capillary plexus (DCP) after each injection significantly correlated with increased logMAR VA (worse VA). CONCLUSION: Anti-VEGF therapy in CRVO patients not only mitigates macular edema but also alters the overall microvascular morphology and functionality as revealed by WF SS-OCTA.
BACKGROUND AND OBJECTIVE: We sought to establish normative quantitative contrast sensitivity function (qCSF) values in healthy adult eyes and investigate the effect of age on qCSF. PATIENTS AND METHODS: Healthy eyes underwent qCSF testing (adaptive sensory technology) and Snellen's visual acuity (VA). Descriptive statistics and mixed-effects multivariable linear regressions were evaluated. RESULTS: A total of 334 eyes (290 patients) with median age 61 years (range 21 to 88) had qCSF values as follows: area under the log contrast sensitivity function curve: 1.18; contrast acuity: 1.32; contrast sensitivity (CS) at 1 cycle per degree (cpd): 1.32; CS at 1.5 cpd: 1.37; CS at 3 cpd: 1.38; CS at 6 cpd: 1.20; CS at 12 cpd: 0.69; CS at 18 cpd: 0.22. Linear reductions in qCSF values per decade of age ranged from -0.02 to -0.07 vs 0.01 for visual acuity (VA). Age had a greater effect on the majority of qCSF values than VA (beta standardized regression coefficient ranged from -0.309 to -0.141 for qCSF values vs 0.177 for VA). CONCLUSIONS: We herein establish a normative database for qCSF and quantify the effect of age on qCSF values, adding evidence towards the validation of qCSF as a clinical endpoint. [Ophthalmic Surg Lasers Imaging Retina 2024;55:212-219.].
Aging , Contrast Sensitivity , Visual Acuity , Humans , Contrast Sensitivity/physiology , Adult , Female , Male , Middle Aged , Visual Acuity/physiology , Aged , Young Adult , Aged, 80 and over , Aging/physiology , Healthy Volunteers , Reference Values , Databases, Factual
PURPOSE: To investigate associations between contrast sensitivity (CS) and vascular metrics on wide-field swept-source optical coherence tomography angiography (WF-SS-OCTA) in patients with retinal vein occlusion (RVO). METHODS: This prospectively recruited, cross-sectional observational study included RVO patients who underwent quantitative CS function (qCSF) testing and WF-SS-OCTA using 3 × 3, 6 × 6, and 12 × 12 mm angiograms on the same day. The study measured several qCSF outcomes and WF-SS-OCTA vascular metrics, including vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ). The data were analyzed using multivariable regression analysis controlling for age and central subfield thickness (CST). RESULTS: A total of 43 RVO eyes of 43 patients and 30 fellow eyes were included. In RVO eyes, multiple vascular metrics were associated with CS outcomes but not visual acuity (VA). On 12 × 12 images, CS thresholds at 1 cpd, 1.5 cpd, and 3 cpd were significantly associated with VD and VSD, but VA was not. When comparing standardized regression coefficients, we found that vascular metrics had a larger effect size on CS than on VA. For instance, the standardized beta coefficient for FAZ area and CS at 6 cpd (ß* = - 0.46, p = 0.007) was larger than logMAR VA (ß* = 0.40, p = 0.011). CONCLUSION: Microvascular changes on WF-SS-OCTA in RVO had a larger effect size on CS than VA. This suggests CS may better reflect the microvascular changes of RVO compared to VA. qCSF-measured CS might be a valuable adjunct functional metric in evaluating RVO patients.
Macula Lutea , Retinal Vein Occlusion , Humans , Contrast Sensitivity , Retinal Vein Occlusion/diagnosis , Tomography, Optical Coherence , Cross-Sectional Studies , Angiography
Purpose: Visual prognosis and treatment burden for macular neovascularization (MNV) can differ between myopic macular degeneration (MMD) and age-related macular degeneration (AMD). We describe and compare MNV associated with MMD and AMD using swept-source (SS)-OCTA. Patients and Methods: Adult patients with documented MNV associated with MMD or AMD were consecutively recruited. Qualitative and quantitative features were assessed from 6x6mm angiograms, including the MNV area and vessel density (VD). Descriptive statistics and linear regression analyses were carried out. Results: Out of 75 enrolled eyes with diagnosed MNV (30 MMD-MNV and 45 AMD-MNV; mean age 55±19 and 75±8 years, respectively), 44 eyes had discernible MNV (11 MMD-MNV and 33 AMD-MNV) on SS-OCTA at the time of the study and were included in the analysis. The MMD-MNV group exhibited a three-fold smaller sized MNV (p=0.001), lower greatest linear dimension (p=0.009) and greatest vascular caliber (p<0.001) compared to AMD-MNVs, and had a higher prevalence of tree-in-bud pattern. Eyes with AMD showed a higher prevalence of type 1 MNVs with medusa pattern. There was no difference in the location of the MNV, shape's regularity, margins, presence of core vessel, capillary fringe, peripheral loops, or perilesional dark halo (p>0.05) between both conditions. After adjustment, decreased MNV area and increased VD were associated with the tree-in-bud pattern, whereas the diagnosis did not significantly influence those parameters. Conclusion: While larger studies are warranted, this study is the first to describe and compare MMD-MNV and AMD-MNV using SS-OCTA, providing relevant clinical insight on MNV secondary to MMD and AMD. These findings also further validate OCTA as a powerful tool to detect and characterize MNV non-invasively.
BACKGROUND/AIMS: We sought to evaluate widefield swept-source optical coherence tomography angiography (WF SS-OCTA) among eyes with concomitant age-related macular degeneration (AMD) and diabetes mellitus or diabetic retinopathy (DM/DR). METHODS: This cross-sectional, comparative study consisted of three study groups: eyes with (1) AMD and DM/DR, (2) AMD alone and (3) DM/DR alone. WF SS-OCTA (3×3, 6×6 and 12×12 mm) images were captured. Vascular metrics included foveal avascular zone (FAZ), vessel density (VD) and vessel skeletonised density (VSD). Mixed-effects multivariable regression models adjusted for age were performed by cohort and subgroup based on AMD and DR stages. RESULTS: Our cohort included 287 eyes from 186 patients with an average age of 64±14.0 years old. Results revealed significantly reduced vascular metrics in concomitant AMD and DM/DR eyes (N=68) compared with AMD-only eyes (N=71) on all angiograms but not compared with DM/DR-only eyes (N=148). For example, when compared with AMD-only eyes, AMD and DM/DR eyes had significantly reduced VD (ß=-0.03, p=0.016) and VSD (ß=-1.09, p=0.022) on 12×12 mm angiograms, increased FAZ perimeter (ß=0.51, p=0.025) and FAZ area (ß=0.11, p=0.015) on 6×6 mm angiogram, and reductions in all VD and VSD metrics on 3×3 and 6×6 mm angiograms. However, only 3×3 mm angiogram FAZ metrics were significantly different when comparing DM/DR eyes with concomitant AMD and DM/DR eyes. CONCLUSION: WF SS-OCTA revealed significant reductions in retinal microvasculature metrics in AMD and DM/DR eyes compared with AMD-only eyes but not compared with DM/DR-only eyes.
Three-Dimensional (3D) heads-up visualization systems have significantly advanced vitreoretinal surgery, providing enhanced detail and improved ergonomics. This review discusses the application of 3D systems in vitreoretinal surgery, their use in various procedures, their combination with other imaging modalities, and the role of this technology in medical education and telementoring. Furthermore, the review highlights the benefits of 3D systems, such as improved ergonomics, reduced phototoxicity, enhanced depth of field, and the use of color filters. Potential challenges, including the learning curve and additional costs, are also addressed. The review concludes by exploring promising future applications, including teleophthalmology for remote assistance and specialist availability expansion, virtual reality integration for global clinical education, and the combination of remotely robotic-guided surgery with artificial intelligence for precise, efficient surgical procedures. This comprehensive review offers insights into the current state and future potential of 3D heads-up visualization systems in vitreoretinal surgery, underscoring the transformative impact of this technology on ophthalmology.
BACKGROUND: With the SARS-CoV-2 pandemic (COVID-19), data on central and peripheral nervous system involvement, including those causing cranial nerve 6 (CN6) palsy, have been limited to case reports. To extract clinically relevant features of COVID-19-related CN6 palsy, we report on a recurrent pediatric case and analysis of reported cases associated with infection or immunization. METHODS: A PubMed search revealed 18 cases of isolated CN6 palsy in addition to the index case (n = 19). Clinical characteristics, workup, and temporal associations between systemic symptoms onset or vaccination, symptoms onset, and resolution were compiled and analyzed. RESULTS: The median age of CN6 onset was 43 years (interquartile range [IQR]: 28-52). Sixteen cases (84.2%) were associated with COVID-19 illness and 3 (15.8%) were associated with COVID-19 vaccination. Four cases (23.5%) had positive neuroimaging findings. The median latency from first COVID-19 symptoms or vaccination to onset of CN6 palsy was 6 days (IQR: 2.3-16), and the median time from onset to resolution was 30 days (IQR: 14-60). Latency to onset of CN6 palsy was significantly and directly associated with time to resolution (R2 = 0.401, P = 0.010). Patients who had a positive SARS-CoV-2 antibody test had significantly longer days from symptoms to onset (6.0 vs 24.5, P = 0.030), and patients with a positive SARS-CoV-2 polymerase chain reaction test had a significantly shorter time to resolution (17.50 vs 90, P = 0.042). CONCLUSIONS: Isolated CN6 palsy from COVID-19 is rare, can occur in infants as young as 7 months, and can be recurrent. Longer latency from systemic symptoms onset portends greater recovery times, and this relationship may reflect multiple mechanisms by which COVID-19 (and/or an immune response thereto) causes cranial neuropathies with direct clinical relevance.
PURPOSE: To evaluate the relationship between contrast sensitivity (CS) and widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vascular metrics in diabetic macular edema (DME) was the purpose. METHODS: This prospectively enrolled cross-sectional observational study included 61 eyes of 48 patients that were tested with the quantitative CS function (qCSF) test on the same day as imaging with WF SS-OCTA (PLEX® Elite 9000, Carl Zeiss Meditec) 3 × 3, 6 × 6, and 12 × 12 mm scans. Outcomes included visual acuity (VA) and multiple qCSF metrics. Vascular metrics included vessel density (VD) and vessel skeletonized density (VSD) in the superficial (SCP) and deep capillary plexus (DCP) and whole retina (WR) and foveal avascular zone (FAZ) parameters. Mixed effects multivariable linear regression models controlling for age, lens status, and diabetic retinopathy stage were performed. Standardized beta coefficients were calculated by refitting the standardized data. RESULTS: SS-OCTA metrics had a significant association with CS and VA. The effect size of OCTA metrics was larger on CS compared to VA. For example, the standardized beta coefficients for VSD and CS at 3 cpd (ßSCP = 0.76, ßDCP = 0.71, ßWR = 0.72, p < 0.001) were larger than those for VA (ßSCP = - 0.55, p < 0.001; ßDCP = - 0.43, p = 0.004; ßWR = - 0.50, p < 0.001). On 6 × 6 mm images, AULCSF, CS at 3 cpd, and CS at 6 cpd were significantly associated with VD and VSD in all three slab types (SCP, DCP, and WR), while VA was not. CONCLUSION: Structure-function associations in patients with DME leveraging the qCSF device suggest microvascular changes on WF SS-OCTA are associated with larger changes in contrast sensitivity than VA.
Purpose: To evaluate the association between contrast sensitivity (CS) and central subfield thickness (CST) in diabetic macular edema (DME). Methods: This prospectively recruited, cross-sectional study included eyes with DME evaluated from November 2018 to March 2021. CST was measured using spectral-domain optical coherence tomography on the same day as CS testing. Only eyes with center-involving DME (CST >305 µm for women; >320 µm for men) were included. CS was evaluated using the quantitative CS function (qCSF) test. Outcomes included visual acuity (VA) and the following qCSF metrics: area under the log CS function, contrast acuity (CA), and CS thresholds at 1 to 18 cycles per degree (cpd). Pearson correlation and mixed-effects regression analyses were performed. Results: The cohort included 52 eyes of 43 patients. Pearson correlation analysis showed a stronger association between CST and CS thresholds at 6 cpd (r = -0.422, P = 0.002) than CST and VA (r = 0.293, P = 0.035). Mixed-effects univariate and multivariate regression analyses showed significant associations between CST and CA (ß = -0.001, P = .030), CS at 6 cpd (ß = -0.002, P = .008), and CS at 12 cpd (ß = -0.001, P = .049) but no significant associations between CST and VA. Among the visual function metrics, the effect size of CST was largest on CS at 6 cpd (ßStandardized = -0.37, P = .008). Conclusions: In patients with DME, CS may be more strongly associated with CST than VA. Including CS as an adjunct visual function outcome measure in eyes with DME may prove clinically valuable.
Purpose: To evaluate the safety, efficacy, and efficiency of the Ngenuity 3-dimensional (3D) heads-up display (HUD) visualization system for primary rhegmatogenous retinal detachment (RRD) repair at a large academic medical center in the United States. Methods: This retrospective review comprised consecutive patients aged 18 years or older who had primary RRD repair (pars plana vitrectomy [PPV] alone or combined PPV and scleral buckle) performed by the same fellowship-trained vitreoretinal surgeon using the 3D visualization system and a traditional standard operating microscope (SOM) at Massachusetts Eye and Ear from June 2017 to December 2021. The minimum follow-up was 90 days. Results: The 3D HUD group comprised 50 eyes of 47 patients and the SOM group, 138 eyes of 136 patients. There were no between-group differences in single surgery anatomic success rates at 3 months (98% HUD vs 99% SOM; P = 1.00) or at the last follow-up (94% HUD vs 98% SOM; P = .40). The rate of postoperative proliferative vitreoretinopathy was similar between the 2 groups (3 months: 3% HUD vs 5% SOM, P = .94; last follow-up, 2% HUD vs 3% SOM, P = .93). There was no difference in the mean duration of surgery (57.4 ± 28.9 minutes HUD vs 59.4 ± 29.9 minutes SOM; P = .68). Conclusions: Anatomic and functional outcomes, in addition to surgical efficiency, of noncomplex primary RRD repair with a 3D HUD system were similar to those of surgery performed with an SOM.
BACKGROUND: Aicardi syndrome is a neurodevelopmental disorder characterized by a triad of partial or complete agenesis of the corpus callosum, infantile spasms, and pathognomonic chorioretinal lacunae. METHODS: Examination, multimodal imaging, and genetic testing were used to guide diagnosis. RESULTS: We report a case of a pediatric patient who was initially diagnosed with refractory infantile spasms. The patient was unresponsive to conventional antiepileptic therapy, and genetic testing with whole exome and mitochondrial genome sequencing could not identify the underlying cause, so vigabatrin was initiated. The ophthalmic examination under anesthesia for vigabatrin toxicity screening revealed chorioretinal atrophy in the retinal periphery of both eyes, with two 3-disc diameter chorioretinal lacunae superotemporal and inferonasal to the optic nerve in the left eye. Given the neuroimaging findings of corpus callosum hypoplasia with polymicrogyria and ocular findings, the patient was diagnosed with Aicardi syndrome. Genetic testing revealed a novel duplication event at the Xp22 locus. CONCLUSIONS: Aicardi syndrome, albeit a rare condition, should always be considered in the differential diagnosis when investigating a female child with refractory seizures in early childhood. Genetic testing may help further our understanding of AIS and the search for a genetic etiology.
Aicardi Syndrome , Spasms, Infantile , Child, Preschool , Female , Humans , Child , Aicardi Syndrome/diagnosis , Aicardi Syndrome/genetics , Spasms, Infantile/diagnosis , Spasms, Infantile/genetics , Vigabatrin , Retina , Anticonvulsants , Short Stature Homeobox Protein
PURPOSE: Data from healthy eyes is needed to interpret optical coherence tomography angiography (OCTA) findings. However, very little normative data is available for wide-field swept-source OCTA (WF SS-OCTA), particularly 12 × 12-mm and disc-centered angiograms. Therefore, we aim to report quantitative metrics in a large sample of control eyes. METHODS: In this cross-sectional observational study, 482 eyes of 375 healthy adults were imaged on the 100 kHz Zeiss PLEX® Elite 9000 using protocols centered on the fovea (3 × 3, 6 × 6, and 12 × 12-mm) and optic disc (6 × 6 and 12 × 12-mm) between December 2018 and January 2022. The ARI Network (Zeiss Portal v5.4) was used to calculate vessel density (VD) and vessel skeletonized density (VSD) in the superficial capillary plexus, deep capillary plexus, and whole retina, as well as foveal avascular zone (FAZ) parameters. Mixed-effect multiple linear regression models were used for statistical analysis. RESULTS: The subjects' median age was 55 (38-63) years, and 201 (53.6%) were female. Greater age and worse best-corrected visual acuity (BCVA) were associated with significantly lower VD and VSD (p < 0.05). VD and VSD differed based on race and cataract status, but not sex, on some scan protocols (p < 0.05). FAZ circularity decreased with age, and FAZ dimensions differed based on race and ethnicity in certain scan protocols. CONCLUSIONS: We report a large database of parafoveal and peripapillary vascular metrics in several angiogram sizes. In referencing these values, researchers must consider characteristics such as age, race, and BCVA, but will have a valuable point of comparison for OCTA measurements in pathologic settings.
Retinal Vessels , Tomography, Optical Coherence , Humans , Adult , Female , Middle Aged , Male , Fluorescein Angiography/methods , Retinal Vessels/pathology , Tomography, Optical Coherence/methods , Cross-Sectional Studies , Benchmarking , Visual Acuity
Immune recovery uveitis (IRU) is an ocular form of immune reconstitution inflammatory syndrome, which is rare in the pediatric population. We report a case of IRU in an 11-year-old girl with a history of cytomegalovirus (CMV) retinitis in the setting of acute leukemia, who developed uveitis, vitritis, retinitis, and vasculitis during immune reconstitution. She was found to have negative CMV antigenemia, and the disease occurred during concurrent systemic antiviral therapy. Anterior chamber tap confirmed the absence of the CMV in the eye, and recurrent blood samples continued to reveal absent CMV viral particles systemically while her lymphocyte count was steadily increasing. The patient responded to oral steroids, leading to resolution of active retinitis. Tapering the steroids caused a mild reactivation of the ocular immune response.
Cytomegalovirus Retinitis , Leukemia , Uveitis , Female , Humans , Child , Cytomegalovirus Retinitis/drug therapy , CD4 Lymphocyte Count , Uveitis/drug therapy , Antiviral Agents/therapeutic use , Vitreous Body , Leukemia/complications , Leukemia/drug therapy
PURPOSE: To investigate structure-function associations between retinal thickness, visual acuity (VA), and contrast sensitivity (CS), using the quantitative contrast sensitivity function (qCSF) method in patients with idiopathic epiretinal membrane (ERM). METHODS: Retrospective, cross-sectional observational study. Patients with a diagnosis of idiopathic ERM were included. Patients underwent complete ophthalmic examination, spectral-domain optical coherence tomography imaging (SD-OCT) (SPECTRALIS® Heidelberg), and CS testing using the qCSF method. Outcomes included area under the log CSF (AULCSF), contrast acuity (CA), and CS thresholds at 1, 1.5, 3, 6, 12, and 18 cycles per degree (cpd). RESULTS: A total of 102 eyes of 79 patients were included. Comparing standardized regression coefficients, retinal thickness in most ETDRS sectors was associated with larger reductions in AULCSF, CA, and CS thresholds at 3 and 6 cpd than those in logMAR VA. These differences in effect on VA and CS metrics were more pronounced in the central subfield and inner ETDRS sectors. Among the retinal layers, increased INL thickness had the most detrimental effect on visual function, being significantly associated with reductions in logMAR VA, AULCSF, CA, and CS thresholds at 3 and 6 cpd (all p < .01), as well as at 1.5 and 12 cpd (p < .05). CONCLUSION: Retinal thickness seems to be associated with larger reductions in contrast sensitivity than VA in patients with ERM. Measured with the qCSF method, contrast sensitivity may serve as a valuable adjunct visual function metric for patients with ERM.
Epiretinal Membrane , Humans , Epiretinal Membrane/diagnosis , Contrast Sensitivity , Retrospective Studies , Cross-Sectional Studies , Retina
Purpose: The guarded light pipe is a recently described alternative endoillumination technique to chandelier illumination. We sought to compare the outcomes of scleral buckling (SB) under indirect ophthalmoscopy (ID) to heads-up three-dimensional visualization with a guarded light pipe (3DGLP). Methods: A retrospective comparative study was performed, including 47 eyes that underwent SB for rhegmatogenous retinal detachment (RRD) repair with either traditional ID (n = 31) or 3DGLP (n = 16). Results: The single surgery anatomic success rate was 87.0% in the ID group and 87.5% in the 3DGLP group. The final anatomic success rate was 100% in both groups. The median (interquartile range) post-operative logMAR was 0.10 (0.0-0.20) in the ID group and 0.08 (0.02-0.69) in the 3DGLP group (p = 0.51). The median operative time was 107 (94-123) minutes in the ID group and 100 (90-111) minutes in the 3DGLP group (p = 0.25). Among eyes that underwent subretinal fluid drainage, the operative time was significantly longer in the ID group compared to the 3DGLP group, 113 (100-135) minutes vs 93 (85-111) minutes (p = 0.035). There were no post-operative complications in the ID group and one complication of self-resolving vitreous hemorrhage associated with a malfunctioning cryoprobe in the 3DGLP group (p = 0.34). There were no cases of post-operative cataract progression in either group. Conclusion: Compared to traditional SB, 3DGLP improves ergonomics and educational value with similar anatomical, visual, intra and post-operative outcomes and may result in shorter operative time in cases requiring subretinal fluid drainage.
BACKGROUND/OBJECTIVES: Optical coherence tomography (OCT) uses low coherence interferometry to obtain depth-resolved tissue reflectivity profiles (M-mode) and transverse beam scanning to create images of two-dimensional tissue morphology (B-mode). Endoscopic OCT imaging probes typically employ proximal or distal mechanical beam scanning mechanisms that increase cost, complexity, and size. Here, we demonstrate in the gastrointestinal (GI) tracts of unsedated human patients, that a passive, single-fiber probe can be used to guide device placement, conduct device-tissue physical contact sensing, and obtain two-dimensional OCT images via M-to-B-mode conversion. MATERIALS AND METHODS: We designed and developed ultrasmall, manually scannable, side- and forward-viewing single fiber-optic probes that can capture M-mode OCT data. Side-viewing M-mode OCT probes were incorporated into brush biopsy devices designed to harvest the microbiome and forward-viewing M-mode OCT probes were integrated into devices that measure intestinal potential difference (IPD). The M-mode OCT probe-coupled devices were utilized in the GI tract in six unsedated patients in vivo. M-mode data were converted into B-mode images using an M-to-B-mode conversion algorithm. The effectiveness of physical contact sensing by the M-mode OCT probes was assessed by comparing the variances of the IPD values when the probe was in physical contact with the tissue versus when it was not. The capacity of forward- and side-viewing M-mode OCT probes to produce high-quality B-mode images was compared by computing the percentages of the M-to-B-mode images that showed close contact between the probe and the luminal surface. Passively scanned M-to-B-mode images were qualitatively compared to B-mode images obtained by mechanical scanning OCT tethered capsule endomicroscopy (TCE) imaging devices. RESULTS: The incorporation of M-mode OCT probes in these nonendoscopic GI devices safely and effectively enabled M-mode OCT imaging, facilitating real-time device placement guidance and contact sensing in vivo. Results showed that M-mode OCT contact sensing improved the variance of IPD measurements threefold and side-viewing probes increased M-to-B-mode image visibility by 10%. Images of the esophagus, stomach, and duodenum generated by the passively scanned probes and M-to-B-mode conversion were qualitatively superior to B-mode images obtained by mechanically scanning OCT TCE devices. CONCLUSION: These results show that passive, single optical fiber OCT probes can be effectively utilized for nonendoscopic device placement guidance, device contact sensing, and two-dimensional morphologic imaging in the human GI tract in vivo. Due to their small size, lower cost, and reduced complexity, these M-mode OCT probes may provide an easier avenue for the incorporation of OCT functionality into endoscopic/nonendoscopic devices.
Fiber Optic Technology , Tomography, Optical Coherence , Biopsy , Endoscopes , Endoscopy , Humans
