Background: This study aims to compare the effect of conventional corneal collagen cross-linking (CXL) with accelerated corneal collagen cross-linking in treatment of keratoconus. Design: A comparative interventional study was employed. Participants: Participants were consecutive cases of progressive keratoconus receiving either conventional (3 mW/cm(2) irradiance for 30 min) or accelerated CXL (9 mW/cm(2) irradiance for 10 min). Methods: Clinical and topographic parameters were compared between the two groups. Postoperative corneal stromal demarcation line was measured using anterior segment optical coherence tomography. Main Outcome Measures: Clinical and topographic parameters such as corrected distant visual acuity (CDVA), maximum keratometry (Kmax), mean keratometry (Kmean), demarcation line depth were gathered from medical records. Results: There were a total of 26 eyes with an average follow up of 13.9 +/- 6.3 months. Fourteen eyes received conventional CXL, and 12 eyes had accelerated CXL. In the conventional CXL group, CDVA improved significantly (P = 0.021). There was also a significant reduction in Kmax (P = 0.003) and Kmean (P = 0.002). In the accelerated CXL group, no significant changes were found in CDVA (P = 0.395), Kmax (P = 0.388) and Kmean (P = 0.952) postoperatively. A significantly greater reduction in Kmax and Kmean were seen in conventional CXL compared to its accelerated counterpart (P = 0.001 and 0.015, respectively). The demarcation line was deeper in eyes with conventional CXL (P = 0.013), and the depth correlated significantly with the change in Kmean (r = -0.432, P = 0.045). Conclusion: Conventional and accelerated CXL are effective in stabilizing keratoconus progression after a mean of 12 months. Patients undergoing conventional CXL showed clinical improvement with greater corneal flattening, which correlated with a deeper corneal stromal demarcation line. This current study is the first to report such correlation.
Background To investigate the safety and efficacy of the Catalys (Optimedica, Santa Clara, CA, USA) femtosecond laser-assisted cataract surgery system compared with conventional phacoemulsification cataract extraction. Design Prospective, consecutive, parallel cohort study. Participants The first 200 eyes undergoing conventional cataract surgery to the first 200 eyes undergoing femtosecond laser-assisted cataract surgery between April and July 2012. Methods Femtosecond laser-assisted cataract surgery involved anterior capsulotomy and lens fragmentation based on optical coherence tomography-guided treatment mapping. Conventional cataract surgery involved manual continuous curvilinear capsulorhexis. Both procedures were completed by standard phacoemulsification and insertion of an intraocular lens. Main Outcome Measures Effective phacoemulsification time and intraoperative complication rates. Results Patient demographics were similar between both groups. There was no statistically significant difference in intraoperative complications between femtosecond laser-assisted cataract surgery and conventional surgery. There was one posterior capsule rupture in both groups (0.5%; not significant). One hundred per cent of cases treated with the femtosecond laser had a complete capsulotomy. Vacuum time decreased with experience. Effective phacoemulsification time was reduced by 70% in the femtosecond group (P<0.0001). Twenty-six cases in the femtosecond group versus one case in the conventional group had 0 effective phacoemulsification time (P<0.0001). Conclusion Femtosecond laser-assisted cataract surgery appears to be as safe as conventional cataract surgery in the short term and results in significantly lower effective phacoemulsification time. Although it may allow for greater efficiency and decreased postoperative complications, further research is needed into long-term safety aspects such as corneal endothelial cell loss.
BackgroundTo evaluate and classify image artefacts in optical coherence tomography (OCT) angiography (OCTA) of the choroid in a group of patients with macular diseases. DesignRetrospective observational study. ParticipantsFive patients with age-related macular degeneration, three with central serous retinopathy, one with polypoidal choroidal vasculopathy and one with multiple evanescent white dot syndrome. MethodsOCTA and OCT reflectivity (OCTR) maps were reviewed along with their fluorescein angiography and indocyanine green angiography. Sixty OCTA images (20 outer retina, 20 Sattler and 20 Haller layers) were graded for image artefacts by two examiners independently. Main Outcome MeasuresOCTA artefacts and their correlation with OCTR maps, angiography and OCT B-scans. ResultsArtefacts (frequency) were classified into (i) motion (70-100%), (ii) fringe washout (100%), (iii) decorrelation projection (0-20%), (iv) masking and unmasking (50-65%) and (v) stromal decorrelation signal (100%). Motion artefact in OCTA is characterized by horizontal dark lines or bands not apparent on OCTR map. Fringe washout creates signal void within choroidal vessels because of fast blood flow. Decorrelation projection from retinal vasculature and choroidal new vessels above the Bruch's membrane are seen within the choroidal OCTA image. Masking and unmasking artefacts occur in regions of pigment epithelial detachment and atrophy. Decorrelation signals can also be seen in the choroidal stroma. ConclusionsOur classification system of artefact in choroidal OCTA establishes a common terminology for clinical interpretation. This is important in enhancing our understanding of the principles of OCTA acquisition, and it also serves as a bench mark for reading centres.
BackgroundTo examine the association of diabetes and diabetic retinopathy (DR) with retinal ganglion cell (RGC) loss. DesignObservational case-control study. ParticipantsType 2 diabetes cases and age-gender matched controls without diabetes. MethodsSpectral-domain optical coherence tomography (OCT) parameters of RGCs were calculated after automated segmentation of macular scans. DR severity was graded on fundus photographs using the modified Airlie House Classification system. Generalized estimating equation was used to compare OCT parameters between cases and controls, adjusted for covariates. Main Outcome MeasuresAverage ganglion cell-inner plexiform layer (GC-IPL) and average retinal nerve fibre layer (RNFL) thicknesses. ResultsWe analyzed 227 cases and 227 controls. The mean age (years) of cases was 58.3 and controls was 58.1 (P=0.13). Among cases, 101 had none, 25 had mild and 101 had moderate or severe DR. Compared with controls, GC-IPL and RNFL were thinner in all cases [mean difference (95% confidence interval [CI]): GC-IPL -4.49 mu m (-2.92; -6.06), RNFL -0.93 mu m (-0.09; -1.85)], including cases with no DR [mean difference (95% CI), GC-IPL -4.37 mu m (-2.72; -6.02), RNFL -1.06 mu m (-0.10; -2.02)]. Cases with any DR had thinner GC-IPL than controls [mean difference (95% CI): GC-IPL -4.81 mu m (-2.12; -7.50)]. Among cases, subjects with moderate or severe DR had thinner GC-IPL than subjects with no DR [mean difference (95% CI): GC-IPL -2.07 mu m (-0.08; -4.07)]. ConclusionsRGC loss is present in subjects with diabetes and no DR, and is progressive in moderate or severe DR. RGC neuronal damage in diabetes and DR can be clinically detected using OCT.
ImportanceAsian Indians are the fastest growing migration groups in the world. Studies evaluating the impact of migration on disease outcomes in this population are rare. BackgroundWe describe the methodology of the Singapore Indian Eye Study-2 (SINDI-2) aimed to evaluate the impact of migration status on diabetic retinopathy and other major age-related eye diseases in Asian Indians living in an urban environment. DesignPopulation-based cohort study. ParticipantsA total of 2200 adults had participated in baseline SINDI (2007-2009, mean age [range]=57.8 [42.7-84.1]years) and SINDI-2 (2013-2015, 56.5 [48.4-90.2]years). MethodsParticipants were classified as first generation' if they were Indian residents born outside of Singapore and as second-generation' immigrants (59.7% in SINDI vs. 63.6% in SINDI-2) if they were born in Singapore. Main Outcome MeasuresResponse rate, participant characteristics and prevalence of systemic diseases were stratified by migration status. ResultsOf the 2914 eligible SINDI participants invited to participate, 2200 participated in SINDI-2 (response rate of 75.2%). In both SINDI and SINDI-2, compared with first-generation immigrants, second-generation immigrants were younger, less likely to have income <1000 SGD, had lower levels of pulse pressure, higher levels of high-density lipoprotein cholesterol, had lower prevalence of hypertension and chronic kidney disease and had higher prevalence of current smoking and obesity (all P<0.05). Conclusions and RelevanceIn both SINDI and SINDI-2, second-generation immigrants had lower prevalence of cardiovascular risk factors except smoking and obesity compared with first-generation immigrants. The final report will confirm if these differences between generations are evident with regard to eye diseases.
BackgroundTo assess the chorioretinal thickness changes using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the association between these structural changes and cognitive impairment in Alzheimer's disease (AD). DesignProspective, cross-sectional study ParticipantsThirty-one eyes of 31 consecutive patients with AD and 30 eyes of 30 cognitively healthy age-matched control subjects were recruited MethodsSD-OCT (RTVue-100) was used to measure the macular ganglion cell complex thickness (mGCC), outer retinal thickness (ORL), and the choroidal thickness (CT). Cognitive function was evaluated by Mini-Mental State examination (MMSE) on the same day of the optical examination. Main Outcome MeasuresChorioretinal thickness. ResultsThe mGCC average, mGCC superior and mGCC inferior thicknesses of the AD group were significantly thinner than those of the controls (all, P0.05). ConclusionsPatients with AD had chorioretinal structural alterations. Retinal structural alterations were seen only in the inner layers. The reduction in mGCC thickness parameters were related to the severity of cognitive impairment in AD.
BackgroundThe aim of the study was to determine plasma nitric oxide (NO) and lipid peroxide (LPO) levels in diabetic retinopathy and its association with severity of disease. DesignProspective observational study. ParticipantsA total of 60 consecutive cases and 20 healthy controls were included. MethodsSeverity of retinopathy was graded according to early treatment diabetic retinopathy study (ETDRS) classification. Photoreceptor inner segment ellipsoid band (ISel) disruption and retinal pigment epithelium (RPE) alteration were graded using spectral domain optical coherence tomography. Data were statistically analyzed. Main Outcome MeasuresPlasma thiobarbituric acid reactive substances, NO assay and reduced glutathione (GSH) were measured using standard protocol. ResultsIncreased severity of diabetic retinopathy was significantly associated with increase in plasma levels of LPO (P<0.05), NO (P<0.001) and decrease in plasma levels of GSH (P<0.0001), ISel disruption (P<0.001) and RPE topographic alteration (P<0.01). ConclusionIncreased plasma NO levels are associated with increased severity of diabetic retinopathy. For the first time, it has been demonstrated that increased plasma LPO, NO and decreased GSH levels are associated with in vivo structural changes in inner segment ellipsoid and RPE.
BackgroundTo evaluate outcomes of Trabectome on pigmentary glaucoma (PG) patients compared to matched controls with primary open angle glaucoma (POAG). DesignProspective comparison study ParticipantsA total of 101 POAG cases were matched with 101 PG cases. MethodsData of the patients diagnosed with PG or POAG was obtained from Trabectome Study Group Database. A one-to-one exact matching was performed between POAG and pigmentary cases based on type of surgery, baseline IOP and baseline number of glaucoma medications. IOP and number of glaucoma medications were compared between groups by Wilcoxon test. Success was defined as IOP21mmHg, at least 20% IOP reduction from baseline for two consecutive visits after 3months and no secondary surgery. Main Outcome MeasuresSuccess rate after Trabectome surgery in PG patients. ResultsBaseline IOP for PG is 24.47.7mmHg and 24.2 +/- 7.5mmHg for POAG (P=1.0), while baseline number of glaucoma medications was 2.8 +/- 1.2mmHg for PG and 2.8 +/- 1.2mmHg for POAG (P=1.0). Postoperative IOP values at 12months were 17.1 +/- 5.0 for PG cases and 15.9 +/- 4.2mmHg for POAG cases. Postoperative number of glaucoma medications at 12month was 2.1 +/- 1.4 in PG cases and 2.4 +/- 1.3 in POAG cases. There was no statistically significant difference between groups in IOP or number of medications at any time point. Survival rate at 12months was 92% and 86% in PG and POAG, respectively (P=0.47). Six PG cases and nine POAG cases required secondary surgery. Conclusion Trabectome provides similar outcomes to PG patients and POAG patients.
ImportanceThis novel endpoint tracks functional vision changes in patients with inherited retinal dystrophies (IRDs) over time. BackgroundThe aims of the study were to determine whether a multi-luminance mobility test (MLMT) can detect functional vision changes over time in subjects with IRDs and to assess natural history and potential effects of investigational agents. DesignThis is a prospective, observational study. ParticipantsSixty-two subjects were enrolled. Sixty (29 normal sighted and 31 visually impaired) were eligible; 54 (28 visually impaired and 26 normal-sighted) completed all testing visits. MethodsSubjects navigated MLMT courses three times over 1year. At each visit, subjects completed testing using individual eyes, and both eyes, at up to nine standardized, increasing luminance levels (range 1 to 400lux). Accuracy and speed were evaluated and compared with visual acuity (VA), visual field (VF) and a visual function questionnaire. Main Outcome MeasuresAccuracy and speed of normal and visually impaired subjects on MLMT, and reliability and content validity of MLMT were the main outcome measures. ResultsMLMT distinguished normal-sighted from visually impaired subjects. All control subjects passed all MLMT attempts at all tested light levels. Visually impaired subjects' performance varied widely; some declined over 1year. Performance declined markedly below certain VA and VF thresholds. Concordance on performance on two baseline visits was high: correlations for accuracy were 94% and 98% for lowest common and highest common lux levels. Conclusions and RelevanceMLMT differentiated visually impaired from control populations and, in visually impaired subjects, identified a range of performances; and tracked performance declines over time, consistent with these progressive conditions.
ImportanceThe XEN-45 implant, a hydrophilic collagen implant which drains aqueous to the subconjunctival space, has not been investigated in the context of uveitic glaucoma. BackgroundTo determine the safety and efficacy of the XEN-45 collagen implant in eyes with uveitic glaucoma. DesignExploratory prospective case series. Participantspatients with medically uncontrolled uveitic glaucoma. MethodsTwenty-four consecutive patients (mean agestandard deviation [SD]=45.318.1years) were implanted with the XEN-45 implant. Main Outcome MeasuresThe primary outcome measure was intraocular pressure (IOP) reduction at 12months as compared to baseline. Secondary outcome measures included ocular hypotensive medication use at 12months, the requirement for further glaucoma surgery and failure. Intraoperative and postoperative complications were documented. ResultsThe baseline mean +/- SD IOP was 30.5 +/- 9.8mmHg and the mean +/- SD number of glaucoma medications required was 3.3 +/- 0.8. In 20 eyes (83.3%) in whom conventional glaucoma surgery was originally perceived to be inevitable, further surgery was not required after XEN-45 implantation. The mean IOP was reduced by 60.2% from baseline to 12.2 +/- 3.1mmHg and mean medication usage was reduced to 0.4 +/- 0.9 at 12months (both P<0.001). One patient had hypotony persisting beyond 2 months that required surgical revision and one patient developed blebitis. The 12-month cumulative Kaplan-Meier survival probability was 79.2%. Conclusions and RelevanceThe XEN-45 implant is effective for the treatment of patients with medically uncontrolled uveitic glaucoma. Potentially sight-threatening complications, including bleb-related ocular infection and persistent hypotony, may occur.
BackgroundTo date, our understanding of the biochemical composition of the living human vitreous relies on extrapolations from animal or human post-mortem studies. MethodsThis was a cross-sectional study of vitreous samples from 27 individuals scheduled for retinal surgery within a tertiary hospital. From each vitreous sample, the concentrations of sodium, potassium, chloride, calcium, magnesium, glucose, lactate, - hydroxybutyrate, copper, zinc, selenium, iron, ferritin and transferrin and osmolality were measured. Perioperative serum samples were also obtained for comparison. ResultsThe following vitreous meanstandard deviation (95% confidence interval of the mean) was observed for each analyte: sodium, 146.7 +/- 3.3 (145.4-148.0) mmol/L; potassium, 5.73 +/- 0.86 (5.39-6.08) mmol/L; chloride, 121.6 +/- 2.6 (120.6-122.7) mmol/L; calcium, 1.128 +/- 0.518 (0.923-1.333) mmol/L; magnesium, 0.900 +/- 0.158 (0.838-0.962) mmol/L; glucose, 2.97 +/- 0.98 (2.58-3.36) mmol/L; lactate, 3.97 +/- 1.09 (3.54-4.40) mmol/L; osmolality, 289.5 +/- 6.9 (286.6-292.5) mOsm/kg; BOHB, 0.0937 +/- 0.0472 (0.0750-0.1124) mmol/L; copper, 0.519 +/- 0.269 (0.412-0.625) mu mol/L; zinc, 1.95 +/- 1.09 (1.52-2.38) mu mol/L; selenium, 0.1035 +/- 0.0276 (0.0923-0.1146) mu mol/L; iron, 3.11 +/- 1.40 (2.56-3.66) mu mol/L; ferritin, 19.5 +/- 10.3 (15.5-23.6) mu g/L; transferrin, 0.0878 +/- 0.0526 (0.0670-0.1086) g/L. Vitreous biochemistry was not significantly different between male and female participants. Vitreous biochemistry was significantly different between non-diabetic and diabetic participants. Vitreous biochemistry was significantly different from the vitreous substitute BSS Plus (Alcon, USA). The vitreous extracted from living humans was markedly different from the commonly reported reference values obtained from animal studies. ConclusionsThe current data provide hitherto unavailable information about the biochemical composition of the living human vitreous.
ImportanceQuality of vision after multifocal intraocular lens (IOLs) implantation in relation to patient satisfaction. It is important to include the evaluation of visual quality and patient satisfaction in clinical practice. BackgroundTo evaluate and compare quality of life and patient satisfaction after implantation of three types of diffractive-refractive and apodized-diffractive bifocal and trifocal multifocal IOLs. DesignComparative, prospective, case series and randomized. ParticipantsHundred and four eyes of 52 patients. MethodsThree multifocal IOLs: AT LISA 809 M (Carl Zeiss Meditec) (AT LISA group, 38 eyes), AT LISAtri 839MP (Carl Zeiss Meditec) (AT LISAtri group, 32 eyes), and ReSTOR SN6AD1 (Alcon) (ReSTOR group, 34 eyes) were implanted after cataract surgery. Main Outcome MeasuresContrast sensitivity, photopic phenomena, patient satisfaction and quality of life criteria were evaluated. ResultsPatient of 88% were satisfied with near and intermediate visual outcomes. Better distance-corrected intermediate visual acuity at 90 cm was detected for AT LISA tri group (P = 0.154). Conclusions and RelevanceContrast sensitivity outcomes and patient satisfaction remained high in the trifocal group when compared to the bifocal IOL groups.
The term aneurysmal type 1 neovascularization is derived from terminology, which is established in the literature but has fallen out of use. We believe that aneurysmal type 1 neovascularization accurately describes the lesions which define the entity known as polypoidal choroidal vasculopathy (PCV). Over the last three decades, the clinical spectrum of PCV has expanded to recognize the occurrence of the aneurysmal (polypoidal) lesions in different contexts, resulting in a complex and unwieldy taxonomy based sometimes on circumstantial findings rather than mechanistic considerations. Advances in multimodal imaging provides increasingly convincing evidence that the lesions which define various forms of PCV are indeed vascular and arise from type 1 neovascular networks. The understanding of PCV as type 1 neovascularization with aneurysms renews focus on the question as to why some patients with type 1 neovascularization develop aneurysms while others do not. Conceptual themes and potential for further study are discussed.
BackgroundThe aim of this study was to compare the efficacy and safety of micropulse and continuous wave diode transscleral cyclophotocoagulation in refractory glaucoma. DesignRandomized, comparative, exploratory study in a tertiary hospital setting. ParticipantsPatients with refractory, end-stage glaucoma. MethodsForty-eight patients were randomized to either treatment. The intraocular pressure, visual acuity, number of medicines and repeat treatment were monitored for 18 months. Complications that include visual acuity decline, prolonged anterior chamber inflammation, phthisis bulbi, scleral thinning and ocular pain were noted. Main Outcome MeasureIntraocular pressure between 6 and 21mmHg and at least a 30% reduction with or without anti-glaucoma medications after 18 months. ResultsA successful primary outcome was achieved in 75% of patients who underwent micropulse cyclophotocoagulation and 29% of patients who received continuous wave cyclophotocoagulation after 12 months (P<0.01). At 18 months, successful outcome was 52% and 30% (P=0.13), respectively. The mean intraocular pressure was reduced by 45% in both groups (P=0.70) from a baseline of 36.5mmHg and 35.0mmHg (P=0.50) after 17.51.6 months (range 16-19) follow up. No significant difference in retreatment rates or number of intraocular pressure lowering medications was noted. The ocular complication rate was higher in continuous wave treated eyes (P=0.01). ConclusionDiode transscleral cyclophotocoagulation in both micropulse and continuous modes was effective in lowering intraocular pressure. The micropulse mode provided a more consistent and predictable effect in lowering intraocular pressure with minimal ocular complications.
Background: To compare the reduction of intraocular pressure (IOP) and glaucoma medications following selective laser trabeculoplasty (SLT) versus standalone placement of the Hydrus microstent, a microinvasive glaucoma surgery device. Design: Prospective interventional case-series. University practice. Participants: Fifty six eyes (56 patients) with uncontrolled primary open-angle glaucoma. Methods: Patients received either SLT (n = 25) or Hydrus implantation (n = 31) in two centres. Patients were evaluated at baseline and 1, 7 days, 1, 3, 6 and 12 months after surgery. Main Outcome Measures: Intraocular pressure and number of glaucoma medications variations intergroups and intra-groups. Results: There were no significant differences at baseline between groups, but the mean deviation was worse in the Hydrus group (-8.43 +/- 6.84 dB, confidence limits (CL) -2.8/-3.3 vs. -3.04 +/- 0.65dB, CL -6/-10.8; P < 0.001). After 12 months, there was a significant decrease in IOP and medications in the Hydrus group compared with baseline values. In the SLT group, only the decrease in IOP was significant. There was 3-fold greater reduction in medication use in the Hydrus group compared with SLT (-1.4 +/- 0.97 vs. -0.5 +/- 1.05, P = 0.001). 47% of patients were medication free at 12 months in the Hydrus group (4% in the SLT group). No complications were recorded in the SLT group. In the Hydrus group, three patients experienced a temporary reduction of visual acuity post-operatively, and two patients had post-operative IOP spikes that resolved within one week. Conclusions: Both SLT and Hydrus implantation reduced IOP without serious adverse events. Hydrus implantation led to a significant and further reduction in medication dependence at 12 months.
ImportanceThis study represents a novel comparison of recently introduced intraocular lens power calculation formulas. BackgroundTo compare current new generation formulas for calculating the intraocular lens power for a standard cohort of patients undergoing cataract and lens replacement surgery in a private group practice in Australia. DesignRetrospective case series comparison. ParticipantsPostoperative results from 400 consecutive patients undergoing implantation of an SN60WF intraocular lens post cataract removal by 12 surgeons were used. MethodsRefractive outcomes were compared with expected targets to determine the predicted refractive outcomes using the Hill-radial basis function, Barrett Universal II and readily available third or fourth generation intraocular lens power calculation formulas. Main Outcome MeasureMean absolute predicted error. ResultsThe mean absolute predicted difference ranged from 0.30 to 0.34D. There was no overall significant difference in the predicted difference or variance between formulas. All formulas achieved greater than 78.3% of eyes within 0.5D of intended refraction. The Hill-radial basis function and Barrett formulas provided the lowest mean numerical error compared with existing formulas in short and long eyes, respectively. The Barrett Universal II formula had the lowest percentage of refractive surprises (>1D from predicted error) across all axial lengths. Conclusions and RelevanceAcceptable outcomes can be achieved with optical biometry, consistent surgical technique and use of current intraocular lens power calculation formulas. The Barrett Universal II formula may provide the lowest risk of refractive surprise compared with other intraocular lens power calculation formulas.
Importance The contribution of the microvascular supply to the pathogenesis of Leber's hereditary optic neuropathy (LHON) is poorly understood. Background We aimed at measuring the peripapillary capillary vessel density (VD) using optical coherence tomography angiography (OCT-A) at different stages of LHON. Design Prospective, cross-sectional, multicenter, observational study. Participants Twenty-two LHON patients divided in four groups: unaffected mutation carriers (LHON-u); early sub-acute stage (LHON-e); late sub-acute stage (LHON-l); chronic stage (LHON-ch). Methods OCT-A scans centred on the optic disc were obtained by spectral domain OCT system. Main Outcome Measures VD, retinal nerve fibre layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL) thickness were compared between groups. Results Significant VD changes were detected in every sector (P < 0.0001). In LHON-e, the VD was reduced in the temporal sector compared with LHON-u and in the temporal and inferotemporal sectors compared with controls. In LHON-l, VD was reduced in whole, temporal, superotemporal and inferotemporal sectors compared with LHON-u and controls. In LHON-ch, the VD was reduced in all sectors compared to the other groups. An asynchronous pattern emerged in the temporal sector with VD changes occurring earlier than RNFL thickness changes and together with GC-IPL thinning. Conclusions and Relevance Significant peripapillary miscrovascular changes were detected over the different stages of LHON. Studying the vascular network separately from fibres revealed that microvascular changes in the temporal sector preceded the changes of RNFL and mirrored the GC-IPL changes. Measurements of the peripapillary vascular network may become a useful biomarker to monitor the disease process, evaluate therapeutic efficacy and elucidate pathophysiology.
Background: The main objective of this study was to test Argus II subjects on three real-world functional vision tasks. Design: The study was designed to be randomized and prospective. Testing was conducted in a hospital/research laboratory setting at the various participating centres. Participants: Twenty eight Argus II subjects, all profoundly blind, participated in this study. Methods: Subjects were tested on the three real-world functional vision tasks: Sock Sorting, Sidewalk Tracking and Walking Direction Discrimination task Main Outcome Measures: For the Sock Sorting task, percentage correct was computed based on how accurately subjects sorted the piles on a cloth-covered table and on a bare table. In the Sidewalk Tracking task, an 'out of bounds' count was recorded, signifying how often the subject veered away from the test course. During the Walking Direction Discrimination task, subjects were tested on the number of times they correctly identified the direction of testers walking across their field of view. Results: The mean percentage correct OFF versus ON for the Sock Sorting task was found to be significantly different for both testing conditions (t-test, P<0.01). On the Sidewalk Tracking task, subjects performed significantly better with the system ON than they did with the system OFF (t-test, P<0.05). Eighteen (18) of 27 subjects (67%) performed above chance with the system ON, and 6 (22%) did so with system OFF on the Walking Direction Discrimination task. Conclusions: Argus II subjects performed better on all three tasks with their systems ON than they did with their systems OFF.
ImportanceThere is a paucity of evidence analysing the treatment of cyclodialysis clefts. BackgroundWe describe outcomes following the treatment of this rare condition at six centres internationally. DesignRetrospective case series. ParticipantsThirty-six patients with a cyclodialysis cleft from 2003 to 2017 were recruited. MethodsClefts were treated with cycloplegic agents, laser therapy and/or surgery. Main Outcome MeasuresPostoperative best recorded visual acuity (BRVA), intraocular pressure (IOP) and the rate of cleft closure. ResultsThe mean age was 4517years and 29 (80.6%) patients were male. One eye (2.8%) received only medical therapy, 5 (13.9%) received laser, 14 (38.9%) underwent surgery after laser failure and 16 (44.4%) eyes received exclusively surgery. Over 80% of eyes had a BRVA improvement of more than two lines. Closure was attained in 30 eyes (93.8%; n=32), with postoperative stabilized IOP12mmHg in 29 eyes (80.6%; n=36) and postoperative BRVA 20/50 in 20 eyes (58.8%; n=34). Improved postoperative BRVA was related to better preoperative BRVA (P =0.006) and preoperative IOP4mmHg (P =0.03). There was no significant difference between treatment approach for IOP12mmHg (P =0.85) or postoperative BRVA 20/50 (P =0.80). Only two eyes at last follow-up required IOP lowering medication. Conclusions and RelevanceThere was a high closure rate with most eyes eventually requiring surgery. Clinically significant improvements in BRVA were found in most eyes. Improved postoperative BRVA was significantly related to better preoperative BRVA and IOP.