Optic Disc Measurements Research Articles

Retinal nerve fiber layer thickness and radial peripapillary capillaries density in myopic adults with optical coherence tomography angiography

PurposeTo evaluate retinal nerve fiber layer thickness (RNFLT) and radial peripapillary capillaries (RPC) density in adults with different degrees of myopia using optical coherence tomography angiography (OCTA) and explore their relationship with ocular factors, such as axial length (AL) and disc area.MethodsA total of 188 subjects were included in this cross-sectional study. The eyes were divided into four groups according to AL. OCTA was used for the assessment of RNFLT, RPC density, and other optic disc measurements, such as disc area. One-way analysis of variance was performed to compare differences between four groups, and P value < 0.01 was considered significant.ResultsThe RNFLT was significantly thinner in high myopia (HM) group at inferior nasal (IN) quadrant (P = 0.004) than low myopia (LM) group, but thicker at temporal inferior (TI) quadrant (P = 0.006). The RPC density of nasal superior (NS) quadrant, nasal inferior (NI) quadrant, and inferior nasal (IN) quadrant significantly decreased as AL increasing. By simple linear regression analysis, the inside disc RPC (iRPC) density tended to be correlated significantly with AL (0.3997%/mm, P < 0.0001). Peripapillary RPC (pRPC) density was in significant correlation with AL (-0.2791%/mm, P = 0.0045), and peripapillary RNFLT (pRNFLT) was in significant correlation with disc area (0.2774%/mm2, P = 0.0001).ConclusionRNFLT and RPC density were closely associated with AL and disc area. They might be new indexes in assessing and detecting myopia development via OCTA.

Detecting Visual Field Worsening From Optic Nerve Head and Macular Optical Coherence Tomography Thickness Measurements.

Compare the use of optic disc and macular optical coherence tomography measurements to predict glaucomatous visual field (VF) worsening. Machine learning and statistical models were trained on 924 eyes (924 patients) with circumpapillary retinal nerve fiber layer (cp-RNFL) or ganglion cell inner plexiform layer (GC-IPL) thickness measurements. The probability of 24-2 VF worsening was predicted using both trend-based and event-based progression definitions of VF worsening. Additionally, the cp-RNFL and GC-IPL predictions were combined to produce a combined prediction. A held-out test set of 617 eyes was used to calculate the area under the curve (AUC) to compare cp-RNFL, GC-IPL, and combined predictions. The AUCs for cp-RNFL, GC-IPL, and combined predictions with the statistical and machine learning models were 0.72, 0.69, 0.73, and 0.78, 0.75, 0.81, respectively, when using trend-based analysis as ground truth. The differences in performance between the cp-RNFL, GC-IPL, and combined predictions were not statistically significant. AUCs were highest in glaucoma suspects using cp-RNFL predictions and highest in moderate/advanced glaucoma using GC-IPL predictions. The AUCs for the statistical and machine learning models were 0.63, 0.68, 0.69, and 0.72, 0.69, 0.73, respectively, when using event-based analysis. AUCs decreased with increasing disease severity for all predictions. cp-RNFL and GC-IPL similarly predicted VF worsening overall, but cp-RNFL performed best in early glaucoma stages and GC-IPL in later stages. Combining both did not enhance detection significantly. cp-RNFL best predicted trend-based 24-2 VF progression in early-stage disease, while GC-IPL best predicted progression in late-stage disease. Combining both features led to minimal improvement in predicting progression.

Individual vs simultaneous macular and optic disc measurements with spectral domain optical coherence tomography in glaucoma and healthy eyes

We assessed the repeatability and agreement of ganglion cell complex (GCC) in the macular area and the peripapillary retinal nerve fiber layer (ppRNFL) with individual and combined macula and disc scans. The macular GCC and ppRNFL thicknesses from 34 control eyes and 43 eyes with glaucoma were measured with the Canon Optical Coherence Tomography (OCT) HS-100. Two repeated measurements were performed with both scan modes. The repeatability limit (Rlim) and agreement analysis were performed. The individual scan showed better repeatability than the combined scan in both groups. However, the differences in the Rlim for the GCC in most sectors were lower than 3 μm (axial resolution of the OCT), and this was larger than 3 μm for most of the ppRNFL sectors. The mean differences in the thickness between both scan modes for the GCC and ppRNFL measurements were less than 3 and 6 μm, respectively. The interval of the limits of agreement was about 10 μm in some sectors for the GCC, and about 40 and 60 μm in some sectors in controls and glaucoma eyes, respectively. Both scan modes showed good repeatability in both groups. The agreement results suggest that the scan modes cannot be used interchangeably.

Optic Nerve Head Morphology is Associated with the Initial Location of Structural Progression in Early Open-Angle Glaucoma.

To investigate the effects of clinical variables on the temporal relationship between macular ganglion cell-inner plexiform layer (mGCIPL) loss and peripapillary retinal nerve fiber layer (pRNFL) loss in glaucoma. Glaucoma eyes with a small cup-to-disc ratio tend to show retinal nerve fiber layer progression earlier than ganglion cell-inner plexiform layer progression. This retrospective observational study used medical records of patients diagnosed with open-angle glaucoma. Structural change was determined using guided progression analysis software of Cirrus optical coherence tomography. Based on the time of detection of pRNFL and mGCIPL changes, eyes showing progressive layer loss were categorized into the pRNFL-first and mGCIPL-first groups. The association between sites of layer thinning and clinical variables such as major retinal arterial angles and several optic disc measurements including disc area, average cup-to-disc ratio (CDR), and vertical CDR were analyzed. A total of 282 eyes were included in the study, of which 104 showed structural progression either in the mGCIPL or pRNFL. Out of these, 49 eyes showed first progression in pRNFL, while 37 eyes showed first progression in mGCIPL. The minimum mGCIPL thickness, pRNFL thickness, average CDR, vertical CDR, and location of progression were significantly different between the two groups (P=0.041, P=0.034, P=0.015, P<0.001, and P<0.001, respectively). In multivariate analysis, average CDR and vertical CDR were significantly associated with the progression site (P=0.033 and P=0.006, respectively). The structural changes in the inferoinferior area and the superior vulnerability zone were significantly associated with RNFL-first progression (P<0.001 for both). The location of layer loss and CDR are related to the layer where loss is first detected (either pRNFL or mGCIPL) in open-angle glaucoma.

Optical Coherence Tomography Angiography for the Differentiation of Glaucoma from Pituitary Macroadenoma Related Optic Disc Measurements

ABSTRACT Objective To determine the potential of optical coherence tomography (OCT) and OCT angiography (OCTA) to distinguish between glaucoma and pituitary macroadenoma by optic disc appearance. Methods This prospective case-control study comprised 31 patients: 23 with glaucoma (18 male, 5 female) and 8 with pituitary macroadenoma and chiasmatic compression (3 male, 5 female). The corresponding mean ages were 72.8 years (range 58–90) and 60.7 years (range 43–73). All participants underwent complete ophthalmological examination, spectral domain OCT and OCTA, and visual field testing. Clinical, imaging, and visual field results were compared between the groups. Results On OCT analysis, the glaucoma group had relatively lower peripapillary retinal nerve fiber layer (RNFL) thickness (65.79 ± 15.46, 86.0 ± 11.37, respectively, P = .002) and lower rim area (1.00 ± 0.22 mm2 and 1.2 ± 0.15 mm2, respectively, P = .005). On OCTA, peripapillary vessel density was significantly lower in all quadrants in the glaucoma group. The significance of these between-group differences was maintained when patients were stratified by visual field mean deviation. Conclusions This is the first comparative analysis of optic disc morphology between glaucoma and pituitary macroadenoma using combined OCT and OCTA. The results yielded lower peripapillary RNFL thickness, lower rim area, and lower peripapillary vessel density in the glaucoma group. These parameters may aid in the initial differentiation between these two optic neuropathies.

Optic disc, macula and ganglion cell layer measurements obtained with optical coherence tomography in patients with thyroid disorder

Purpose: The aim of this study was to compare retinal nerve layer thickness, central macula thickness and ganglion cell layer measurements using optical coherence tomography (OCT) between thyroid patients and age- and sex-matched healthy controls.&#x0D; Materials and Methods: Eighty eyes of 80 patients in the thyroid patient group and 48 eyes of 48 patients in the control group were included in the study. After evaluating the exclusion criteria, visual acuity, anterior segment biomicroscopy, intraocular pressure, fundoscopy and spectral field optic coherence tomography (SF-OCT) imaging tests were performed on all patients included in the study. These data have been recorded. Central macular thickness (CMT), retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) measurements were evaluated by statistical methods for both groups.&#x0D; Results: There was no statistically significant difference between the demographic data of the groups included in the study. IOP measurements were found to be statistically significantly higher in the patient group compared to the control group. CMT values were 258.2±16.1 µm in the patient group and 273.1±23.8 µm in the control group, and statistically significant differences were observed between the groups. &#x0D; Conclusion: The findings supports that changes in the optic nerve and macula develop before vision loss in TO patients compared to the healthy control group. We can follow TO patients more objectively and reliably and make treatment planning more accurately by adding OCT, which is a noninvasive test, to our clinical practice, since structural changes develop before functional deterioration in TO patients.

Optic Disc Measurements in Children by Optical Coherence Tomography.

This study showed the distribution of optic disc indices in a population-based sample of Iranian children in detail. Refractive errors and biometric components are among the ocular factors that are related to these indices. To determine the normative value of optic nerve indices in children and their association with ocular and demographic factors. A cross-sectional study was conducted in 2018. Biometry was done using the Allegro Biograph, and macular indices were measured by OCT imaging. After applying the exclusion criteria, 9051 eyes of 4784 children were analyzed. The mean±SD and 95% confidence intervals (in parentheses) of vertical cup-to-disc ratio, average cup-to-disc ratio, rim area, disc area, and cup volume were 0.45±0.15(0.45-0.46) mm, 0.43±0.14 (0.42-0.43) mm, 1.46±0.25 (1.45-1.47) mm 2 , 1.92±0.35 (1.91-1.93) mm 2 , and 0.14±0.14 (0.14-0.15) mm 3 , respectively. Vertical cup-to-disc ratio and average cup-to-disc ratio had a positive association with intraocular pressure (IOP) (both βs=0.003), and a negative association with retinal nerve fiber layer thickness (both βs=-0.001), central corneal thickness (CCT) (both βs=-0.001), anterior chamber depth (β=-0.025 and β=-0.027, respectively), lens thickness (β=-0.034 and β=-0.032, respectively), and mean keratometry (MK) (both βs=-0.015). The average cup-to-disc ratio had a positive association with height (β=0.001). Rim area had a negative association with increased age (β=-0.008), axial length (β=-0.065), IOP (β=-0.009), and MK (β=-0.014) and a positive association with macular volume (β=0.021), retinal nerve fiber layer thickness (β=0.004), and CCT (β=0.001). Disc area had a positive association with macular volume (β=0.031) and a negative association with female sex (β=-0.037), axial length (β=-0.087), anterior chamber depth (β=-0.112), lens thickness (β=-0.059), and MK (β=-0.048). The results of generalized estimating equations showed that cup volume was smaller in girls (β=-0.009), and had a positive association with height (β=0.001), IOP (β=0.003) and negative association with CCT (β=-0.0001) and MK (β=-0.012). The results provided the normative values of optic disc indices in children. Demographic factors, biometric components, IOP, SBP, and retinal parameters had a significant association with optic disc indices.

Optical coherence tomography reveals retinal thinning in schizophrenia spectrum disorders

BackgroundSchizophrenia spectrum disorders (SSDs) are presumed to be associated with retinal thinning. However, evidence is lacking as to whether these retinal alterations reflect a disease-specific process or are rather a consequence of comorbid diseases or concomitant microvascular impairment.MethodsThe study included 126 eyes of 65 patients with SSDs and 143 eyes of 72 healthy controls. We examined macula and optic disc measures by optical coherence tomography (OCT) and OCT angiography (OCT-A). Additive mixed models were used to assess the impact of SSDs on retinal thickness and perfusion and to explore the association of retinal and clinical disease-related parameters by controlling for several ocular and systemic covariates (age, sex, spherical equivalent, intraocular pressure, body mass index, diabetes, hypertension, smoking status, and OCT signal strength).ResultsOCT revealed significantly lower parafoveal macular, macular ganglion cell–inner plexiform layer (GCIPL), and macular retinal nerve fiber layer (RNFL) thickness and thinner mean and superior peripapillary RNFL in SSDs. In contrast, the applied OCT-A investigations, which included macular and peripapillary perfusion density, macular vessel density, and size of the foveal avascular zone, did not reveal any significant between-group differences. Finally, a longer duration of illness and higher chlorpromazine equivalent doses were associated with lower parafoveal macular and macular RNFL thickness.ConclusionsThis study strengthens the evidence for disease-related retinal thinning in SSDs.

Graph deep network for optic disc and optic cup segmentation for glaucoma disease using retinal imaging.

The fundus imaging method of eye screening detects eye diseases by segmenting the optic disc (OD) and optic cup (OC). OD and OC are still challenging to segment accurately. This work proposes three-layer graph-based deep architecture with an enhanced fusion method for OD and OC segmentation. CNN encoder-decoder architecture, extended graph network, and approximation via fusion-based rule are explored for connecting local and global information. A graph-based model is developed for combining local and overall knowledge. By extending feature masking, regularization of repetitive features with fusion for combining channels has been done. The performance of the proposed network is evaluated through the analysis of different metric parameters such as dice similarity coefficient (DSC), intersection of union (IOU), accuracy, specificity, sensitivity. Experimental verification of this methodology has been done using the four benchmarks publicly available datasets DRISHTI-GS, RIM-ONE for OD, and OC segmentation. In addition, DRIONS-DB and HRF fundus imaging datasets were analyzed for optimizing the model's performance based on OD segmentation. DSC metric of methodology achieved 0.97 and 0.96 for DRISHTI-GS and RIM-ONE, respectively. Similarly, IOU measures for DRISHTI-GS and RIM-ONE datasets were 0.96 and 0.93, respectively, for OD measurement. For OC segmentation, DSC and IOU were measured as 0.93 and 0.90 respectively for DRISHTI-GS and 0.83 and 0.82 for RIM-ONE data. The proposed technique improved value of metrics with most of the existing methods in terms of DSC and IOU of the results metric of the experiments for OD and OC segmentation.

Optic Nerve Head Morphology in Adults Born Extreme, Very, and Moderate Preterm With and Without Retinopathy of Prematurity: Results From the Gutenberg Prematurity Eye Study

This study aimed to investigate associations of prematurity and associated factors with optic disc morphology in adulthood as long-term effects. Retrospective cohort study. The Gutenberg Prematurity Eye Study (GPES) is a retrospective cohort study with a prospective ophthalmologic examination of adults (age 18-52 years) in Germany. In every participant, photography of optic discs was performed with a nonmydriatic fundus camera, and optic disc measurements were done manually. The vertical cup-to-disc ratio (VCDR), optic disc area, and torted and tilted discs were assessed and exploratively compared between individuals with retinopathy of prematurity (ROP) with treatment, an ROP group without treatment and groups of individuals of different gestational ages (GAs) without ROP (GA ≤ 28 weeks, GA 29-32 weeks, GA 33-36 weeks, and GA ≥ 37 weeks [control group]). The present analysis included 743 eyes of 393 individuals born preterm and full-term (aged 28.4 ± 8.6 years, 223 females). The VCDR was significantly larger in subjects with a GA ≤28 weeks without ROP compared to the full-term control group (GA ≥37 weeks) (P=.002). Subjects with ROP without treatment also had a larger VCDR (P=.001), whereas those with ROP treatment showed a smaller VCDR than the full-term control group (P=.02). In addition, individuals with ROP treatment were more likely to have a torted disc than the full-term control group (P=.006). The present study provides evidence that individuals born extremely preterm have increased VCDR in adulthood. Furthermore, these results indicate that fetal origins affect optic disc morphology until adulthood, which might predispose the affected individual to degenerative optic nerve head diseases or being incorrectly diagnosed to glaucoma.

The relationship between carotid intima-media thickness and microvascular changes in retinal zones and optic disc in patients with type 1 diabetes mellitus.

The aim of this study was to detect early retinal vascular changes with optical coherence tomography angiography (OCTA) in type 1 diabetes mellitus (T1DM) patients without diabetic retinopathy and to evaluate the correlation of the results with carotid intima-media thickness (IMT). This is a case-control and cross-sectional study. This study included 38 adult patients with T1DM, and 38 age and gender-matched healthy controls. Retinal and optic disc (OD) measurements were taken using OCTA. The carotid artery IMT of each patient was measured using Doppler ultrasonography. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density, foveal avascular zone (FAZ), non-flow area (NFA) and foveal density (FD) were analysed in the fovea centred 6 × 6 mm macular area. The superficial capillary plexus and DCP were also scanned centred on the peripapillary region. The correlations between OCTA measurements and carotid IMT, duration of DM and haemoglobin A1c levels in patients with T1DM were evaluated. The mean values for carotid IMT were significantly higher in diabetic patients than in controls (p < 0.001). The mean values for vessel density SCP, DCP and OD were significantly lower in the diabetic group (p < 0.05). There were correlations between the carotid IMT and duration of T1DM and the evaluated parameters of OCTA. Microvascular changes in the SCP and DCP in patients with T1DM without DR offer important data. OCTA can be used to detect early microvascular changes in patients with T1DM without DR. In addition, a relationship was found between SCP vascular dropout and carotid IMT.

Response to Letter to the Editor: Optic Disc Measures in Obstructive Sleep Apnea: A Community-based Study of Middle-aged and Older Adults.

Response to Letter to the Editor: Optic Disc Measures in Obstructive Sleep Apnea: A Community-based Study of Middle-aged and Older Adults.

Letter to the Editor: Optic Disc Measures in Obstructive Sleep Apnea: A Community-based Study of Middle-aged and Older Adults.

Letter to the Editor: Optic Disc Measures in Obstructive Sleep Apnea: A Community-based Study of Middle-aged and Older Adults.

Evaluation of microvascular changes in retinal zones and optic disc in pediatric patients with type 1 diabetes mellitus.

The objective of this study was to evaluate the vascular parameters of the retinal zones and the optic disc (OD) with the use of optical coherence tomography angiography (OCTA) in pediatric patients with type 1 diabetes mellitus (T1DM). This study enrolled 60 patients with T1DM without clinically detectable diabetic retinopathy (DR), along with 59 age-, gender-, and pubertal stage-matched controls. The ages of the participants in both groups were < 18 years. Retinal and OD measurements were carried out with OCTA. Foveal avascular zone (FAZ) area, non-flow area (NFA), FAZ perimeter (PERIM), acircularity index of FAZ (AI, the rate of the perimeter of FAZ and the perimeter of a circle with equal area), foveal density (FD), superficial (SCP), and the deep capillary plexus (DCP) were analyzed in the macular region. SCP and DCP were also scanned centered on the OD. Correlations between the OCTA parameters with duration of DM, glycated hemoglobin (HbA1c) levels, and microalbuminuria were evaluated among patients with T1DM. The mean values for NFA were significantly higher and mean FD were significantly lower in the diabetic group compared with the controls (p = 0.02 and p = 0.01, respectively). The mean values for SCP and DCP were significantly lower in diabetic group (p < 0.05). The mean values for capillary density in the OD were also significantly lower in diabetic group (p < 0.05). There were correlations between the duration of T1DM, HbA1c levels and microalbuminuria, and the investigated parameters of OCTA. The presence of microvascular changes in both retinal zones and the OD in children with T1DM without retinopathy is an important data. OCTA can be used for the early detection of DR in children.

Retinal, choroidal and optic disc analysis in patients with Graves' disease with or without orbitopathy.

To compare optic disc, retinal and choroidal measurements in patients with Graves' disease with or without orbitopathy, and healthy controls. Optical coherence tomography and Heidelberg retinal tomography were performed in 40 patients with Graves' orbitopathy (GO), 40 subjects with Graves's disease (GD) with no sign of orbitopathy and 40 healthy controls. Degree of exophthalmos, ocular alignment, clinical activity score (CAS), choroidal thickness, retinal thickness, ganglion cell layer (GCL) thickness, disc area, cup area, rim area, cup/disc area ratio, linear cup/disc ratio and mean peripapillary retinal nerve fibre layer thickness were analysed. GO patients and healthy controls significantly differ regarding mean central retinal thickness (275 ± 19µm and 285 ± 20µm, P = 0.017); mean central GCL thickness (14.87 ± 3.0µm and 17.92 ± 5.02µm, P = 0.001); mean disc area (2.00 ± 0.44mm2 and 1.72 ± 0.37mm2, P = 0.003); mean cup area (0.53 ± 0.52mm2 and 0.31 ± 0.20mm2, P = 0.003); cup/disc area ratio (0.22 ± 0.10 and 0.17 ± 0.08, P = 0.010); and linear cup/disc ratio (0.47 ± 0.15 and 0.40 ± 0.13, respectively, P = 0.011). No difference was found between patients without orbitopathy and healthy controls. No significant difference was found regarding the choroidal thickness between the three groups. There was no statistically significant relationship between retinal thickness, ganglion cell layer thickness, mean disc area, mean cup area, cup/disc area ratio, linear cup/disc ratio, CAS, exophthalmometric value and ocular alignment. GO patients showed significant changes in foveal and GCL thickness, and optic nerve head morphology suggesting a possible influence of the orbital inflammatory process.

Recognition of Cardiovascular Diseases through Retinal Images Using Optic Cup to Optic Disc Ratio

In the versatile advanced world, diseases due to the cardiovascular disease (CVD) play a major role in human health disorders event leads to death. CVD deaths accounts for 80% in males and 75% in females. Cardiovascular diseases are the leading cause of death globally. By 2030, over 23 million people will die from CVD every year. Up to 90% of cardiovascular disease may be preventable if they are properly recognized and correct treatment should be given at the earlier stage. This paper undergoes one of the key factors to find CVD is through retinal vessels, the processes involved in those measurements could predict the presence of diseases. The main function that is involved in the retinal vessels is the extraction of information present inside the tissues which is used in the case of recognition and treatment towards cardiovascular diseases such as stroke, blood pressure, hyper tension, glaucoma etc. The retinal image taken is filtered and then segmented. Their result is used for arteries and vein classification through the support vector machine (SVM). By detecting the optic cup and optic disc measurement, cup-to-disc ratio (CDR) is calculated here. By using artificial neural networks (ANN), the presence of CVD is recognized and their parameters are measured. Hence, the presence of CVD is recognized through the retinal images are detected in this paper.

Optic Disc Measures in Obstructive Sleep Apnea: A Community-based Study of Middle-aged and Older Adults.

Previous findings on the link between OSA and increased glaucoma risk have been inconsistent. In a community-based study of middle-aged and older adults, we explored for differences in optic disc measures that may resemble preclinical glaucomatous changes in relation to OSA status and severity. A total of 865 participants (46 to 67 y; 45% male) underwent an at-home sleep study during which their apnea-hypopnea index (AHI) and sleep oxygen saturation level were measured. Participants were determined to have no OSA (AHI<5 events/h), mild (AHI 5 to 15), moderate (AHI 16 to 30), or severe OSA (AHI>30). At a 6-year follow-up visit, the optic discs of both eyes were imaged using spectral domain optic coherence tomography to measure the Bruch membrane opening-minimum rim widths and RNFL thicknesses. On the basis of the AHI, 411 participants (48%) had OSA, of whom 92 (11% of total sample) and 26 (3%) had moderate and severe OSA, respectively. In the multivariate analysis, participants with severe OSA had thinner RNFL superotemporally than those without OSA or with mild OSA (P<0.001 and 0.001, respectively). In addition, superotemporal RNFL was inversely associated with AHI (P=0.004) and sleep time with oxygen saturation level <90% (P=0.005). There was no association between OSA measures and Bruch membrane opening-minimum rim widths. Our findings do not provide strong evidence of a link between measures of OSA and the optic disc. However, the association between increased OSA severity and thinner superotemporal RNFL has been reported consistently in previous studies and thus warrants further evaluation.

Inner retinal thickness and optic disc measurements in obese children and adolescents.

This study aimed to evaluate optic nerve head parameters and inner retinal layer thicknesses in obese children and adolescents. Forty-one eyes of 41 pediatric obese participants and 41 eyes of 41 age- and sex-matched healthy controls were included in this study. Body mass index was calculated, based on sex and age, using body weight and height measurements. Blood lipid values (i.e., cholesterol, low-density lipoprotein, high-density lipoprotein, and triglyceride) were measured in obese participants. Optical coherence tomography was used to examine optic nerve head parameters, including rim area, disc area, cup-to-disc ratio, and cup volume, as well as the thicknesses of retinal nerve fiber layers and macular ganglion cell-inner plexiform layers. Optic disc parameters were similar in obese and healthy children (p>0.05). The percentage of binocular retinal nerve fiber layer thickness symmetry was significantly different between obese and control groups (p=0.003). Compared to the control group, participants in the obese group exhibited thinner retinal nerve fiber layers in the superior quadrants (p=0.04) and thinner ganglion cell-inner plexiform layers in the superior-temporal sectors (p=0.04). There were no statistically significant correlations between the ocular parameters and lipid blood test values assessed in this study (p>0.05). Body mass index was significantly negatively correlated with the mean retinal nerve fiber layer thickness (r=-0.33, p=0.03) in the obese group. There was no significant correlation between intraocular pressure and body mass index (r=0.05, p=0.74). Compared to healthy children, obese children had greater binocular retinal nerve fiber layer thickness asymmetry and thinner retinal nerve fiber and ganglion cell-inner plexiform layers in several sectors. Blood lipid levels were not associated with retinal thickness or optic disc parameters in obese children.

Evaluation of Mobile Electronic Devices in Detecting Optic Disc and Visual Field Parameters in Patients with Glaucoma at a Tertiary Hospital in Northeastern Tanzania

Background: Glaucoma is a serious public health problem since it causes visual impairment impacting social, mental and physical health of an individual. Diagnosis and management of glaucoma continue to be a challenge due to few qualified personnel and high cost of the equipment. The use of portable Eye Examination Kit such as Smartphone and tablets can be used in glaucoma screening for taking high-resolution fundus photos for optic disc and visual field parameters, respectively. This study was conducted to evaluate the applicability of mobile electronic device to detect optic disc and visual field parameters for glaucoma in a resource limited setting. Objective: To evaluate the applicability of mobile electronic devices to detect optic disc and visual field parameters for glaucoma. Methodology: Across-sectional study was conducted at KCMC Eye department from October 2018 to June 2019. Study included 140 participants attending eye clinic of which 67 had glaucoma and 73 without glaucoma. Clinical and socio-demographic data were collected using a structured questionnaire and analysed using Stata 15. Glaucoma examination was made on the right eye and photo comparison made between those with and without glaucoma. PEEK Smartphone fundus photo examination was compared with the gold standard machine (Slit Lamp Biomicroscopy), Amsler grid chart installed on a tablet (Microsoft surface, internal storage 256 GB, 2013) and contrast sensitivity compared with Humphrey field analyser (i series, model 740117434, Carl Zeiss Meditec). Results: The kappa (k) agreement between Slit lump biomicroscopy fundus view image and PEEK Smartphone concerning the optic disc measurement was 0.92 with sensitivity and specificity of 90.32% (95% CI: 80.12 - 96.37) and 93.59% (95% CI: 85.67 - 97.89) with a p < 0.001 respectively. An agreement between Amsler grid and Humphrey Field Analyser was 0.67 with sensitivity of 33.33% (95% CI: 20.76 - 47.92) and specificity of 86.52% (95% CI: 77.63 - 92.83) with a p < 0.005. An agreement for contrast sensitivity and Humphrey Field Analyser was 0.51 with sensitivity of 48.91% (95% CI: 38.3 - 59.56) and specificity of 54.17% (95% CI: 39.17 - 68.63) and p value of 0.729. Conclusion: PEEK Smartphone fundus image specificity was almost in perfect agreement compared with Amsler grid and Contrast sensitivity. The PEEK Smartphone fundus view optic disc parameter for vertical cup to disc ratio has a potential to enhance detection of glaucoma and thus improve its management in resource-limited settings.

Prediction of Glaucoma Progression with Structural Parameters: Comparison of Optical Coherence Tomography and Clinical Disc Parameters

To test the hypothesis that baseline optical coherence tomography (OCT) measures predict visual field (VF) progression in a cohort of patients with suspected or established glaucoma and to compare their performance to semiquantitative optic disc measures. This was an observational cohort study. The setting of this study was an academic institution. The study population included 171 eyes of 95 patients with good-quality baseline retinal nerve fiber layer (RNFL) and macular OCT images and disc photographs with >2 years of follow-up and ≥5 VFs. The observation procedures were baseline macular and RNFL OCT measures and cup-to-disc ratio and disc damage likelihood score. The main outcome measure was prediction of glaucomatous VF deterioration according to trend and event analyses. Median (interquartile range) baseline mean deviation and follow-up were -2.9 (-6.4 to -1.1) dB and 54 (44-65) months, respectively. Seventeen and 25 eyes progressed by final visit based on pointwise event analysis and trend analysis of visual field index (VFI), respectively. Thinner central corneal thickness (P=.005), female gender (P= .015), and thinner average peripapillary RNFL (P= .001) predicted VF progression on proportional hazard models. Thinner RNFL at baseline (P= .006) or thinner average ganglion cell-inner plexiform layer (P= .028) along with higher baseline VFI (P= .018 and .048, respectively) predicted VFI progression. Neither optic disc measures predicted VF progression in any of the explored models. Baseline structural OCT measures predicted subsequent VF progression in contrast to semi-quantitative optic disc measures. OCT-based structural measures should be included in prognostic models of glaucomatous VF deterioration.