Inferotemporal Ganglion Cell-inner Plexiform Layer Thickness Research Articles

EVALUATION OF MACULAR GANGLION CELL COMPLEX USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IN GLAUCOMA SUSPECT PATIENTS AND TO CORRELATE IT WITH NORMAL POPULATION

PURPOSE:. To evaluate macular ganglion cell complex in glaucoma suspect patients and normal population RESULTS The difference between values of neuroretinal rim thickness,rim area,disc area,average CDR,vertical CDR and cup volume among glaucoma suspect and normal (controls) was found to be statistically significant (p value<0.001). The difference between values of superior,nasal,inferior,temporal and average RNFL thickness among glaucoma suspect and normal (controls) was found to be statistically significant(p value<0.001). The difference between values of superotemporal, superior, superonasal, inferonasal, inferior, inferotemporal, average and minimum GCIPL (Ganglion cell Inner plexiform layer) thickness in µm, as estimated on OCT macula, was found to be statistically significant among glaucoma suspect patients and normal (controls) (p value <0.001). Upon applying Spearman’s rho correlation coefficient test in glaucoma suspect patients for GCIPL thickness and RNFL thickness, statistically significant correlation was found between Inferior RNFL thickness with Inferotemporal GCIPL thickness(p value 0.029) and Temporal RNFL thickness with Inferotemporal GCIPL thickness .(p values 0.006). Upon applying Spearman’s rho correlation coefficient test in normal (controls) for GCIPL thickness and RNFL thickness,statistically significant correlation was found between Superior RNFL thickness with Superior GCIPL thickness(p value 0.038), Superior RNFL thickness with Superonasal GCIPL thickness (p values 0.012 ), and Average RNFL thickness with Average GCIPL thickness (p value 0.033) CONCLUSION: In our study we found there is statistically significant reduction in thickness in all measured quadrants of Macular GCIPL and RNFL in glaucoma suspect patients compared to normal. Also, a statistically significant correlation was found between Inferior RNFL thickness with Inferotemporal GCIPL thickness and Temporal RNFL thickness with Inferotemporal GCIPL thickness in glaucoma suspect patients,suggesting good diagnostic ability of inferotemporal macular GCIPL thickness.

Diagnostic ability of macular nerve fiber layer thickness measured by swept-source optical coherence tomography in preperimetric glaucoma.

We evaluated the diagnostic ability of macula retinal nerve fiber layer (mRNFL) thickness in preperimetric glaucoma (PPG) patients. This prospective study included 83 patients with PPG and 83 age- and refractive error-matched normal control subjects. PPG was defined as a localized RNFL defect corresponding to glaucomatous optic disc changes with a normal visual field test. We used spectral-domain (SD) optical coherence tomography (OCT) to measure the circumpapillary RNFL (cpRNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness. Swept-source (SS) OCT was used to measure cpRNFL thickness, macular ganglion cell layer + inner plexiform layer (IPL) thickness (GCL+), and macular ganglion cell layer + IPL+ mRNFL thickness (GCL++). The mRNFL thickness was defined as GCL++ minus GCL+. To evaluate the diagnostic power of each parameter, the area under the receiver operating characteristics curve (AUROC) was analyzed to differentiate PPG from the normal groups. Using SD-OCT, all GCIPL parameters and most cpRNFL parameters, except at the nasal and temporal quadrant, were significantly lower in PPG versus normal controls. PPG eyes had significantly smaller values than normal controls for all cpRNFL and GCL parameters measured by SS-OCT, except mRNFL at the superonasal area. The inferotemporal GCL++ had the largest AUROC value (0.904), followed by inferotemporal GCL+ (0.882), inferotemporal GCIPL thickness (0.871), inferior GCL++ (0.866), inferior cpRNFL thickness by SS-OCT (0.846), inferior cpRNFL thickness by SD-OCT (0.841), and inferotemporal mRNFL thickness (0.840). The diagnostic performance was comparable between inferotemporal mRNFL thickness and the best measures of GCL (inferotemporal GCL++, p = 0.098) and cpRNFL (inferior cpRNFL thickness by SS-OCT, p = 0.546). The diagnostic ability of mRNFL thickness was comparable to that of the best measures of cpRNFL and GCL analysis for eyes with PPG. Therefore, mRNFL thickness could be a new parameter to detect early structural changes in PPG.

Ganglion Cell-inner Plexiform Layer Thickness Measured by Cirrus High-definition Optical Coherence Tomography Enhances Glaucoma Diagnosis in Patients with Moderate or High Myopia

Objective: To assess the diagnostic ability of Cirrus high-definition optical coherence tomography (HD-OCT) parameters in patients with moderate or high myopia for detecting glaucoma, and to compare the thickness of the macular ganglion cell-inner plexiform layer (GC-IPL) in glaucomatous and normal eyes in both types of myopia.Materials and Methods: This prospective study enrolled moderately (spherical equivalent -3.00 to -6.00 diopters) and highly (spherical equivalent ≤ -6.00 diopters) myopic patients without (controls) and with (study) glaucoma. Cirrus HD-OCT was used to determine the thickness of the peripapillary retinal nerve fiber layer (RNFL) and the GC-IPL. The area under the receiver operating characteristic curve was analyzed to evaluate the glaucoma detection capability of each Cirrus HD-OCT parameter.Results: Seventy eyes (31 moderate myopia, 39 high myopia) were included. The parameters with the best diagnostic ability were minimum GC-IPL, inferior RNFL and average RNFL thickness in moderately myopic eyes, and average RNFL, inferior RNFL and inferotemporal GC-IPL thickness in highly myopic eyes. All parameters were thinner in glaucomatous than in normal eyes in both groups.Conclusion: Although macular GC-IPL thickness demonstrated high ability to detect glaucoma in patients with moderate or high myopia, it should be used in combination with other structural imaging and functional assessments for diagnosing glaucoma.

SD-OCT parameters and visual field defect in chiasmal compression and the diagnostic value of neural network model.

To evaluate the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GCIPL) measurements using spectral domain optical coherence tomography (SD-OCT) in patients with chiasmal compression and analyze the diagnostic value of a neural network model. Forty-seven patients with chiasmal compressive disorder were recruited and divided into two groups depending on the visual field defect (perimetric; group 1 and preperimetric; group 2). Fifty-seven normal subjects were also recruited (group 3). Peripapillary RNFL and macular GCIPL were analyzed in each group. A multilayer perceptron was trained using a training dataset and derived a neural network model. The diagnostic performances were compared using the area under the receiver operating curve (AUROC) between each parameters and neural network model. All macular GCIPL parameters, except inferotemporal GCIPL thickness, were thinner in group 1 than in group 2 and group 3, with barely any difference between group 2 and group 3 parameter values. The diagnostic power of the neural network model, minimum GCIPL, and inferonasal GCIPL were superior when compared with other parameters; the diagnostic values of these three parameters are not significantly different in discriminating the patients and normal control. However, the neural network exhibited the best diagnostic power in distinguishing group 2 and group 3. Macular GCIPL was reduced in chiasmal compression patients with visual field defect which was not evident in the preperimetric state. Neural network model showed superior diagnostic value in discriminating the preperimetric patients from normal control. The results suggest that neural networks may be helpful in the early diagnosis of chiasmal compression.

Comparisons of ganglion cell-inner plexiform layer loss patterns and its diagnostic performance between normal tension glaucoma and primary open angle glaucoma: a detailed, severity-based study.

To evaluate the patterns of macular ganglion cell-inner plexiform layer (GCIPL) loss in normal tension glaucoma (NTG) and primary open angle glaucoma (POAG) in a detailed, disease severity-matched way; and to assess the diagnostic capabilities of GCIPL thickness parameters in discriminating NTG or POAG from normal subjects. A total of 157 eyes of 157 subjects, including 57 normal eyes, 51 eyes with POAG and 49 eyes with NTG were enrolled and strictly matched in age, refraction, and disease severity between POAG and NTG groups. The average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal GCIPL thickness, and the average, superior, temporal, inferior, and nasal retinal nerve fiber layer (RNFL) thickness were obtained by Cirrus optical coherence tomography (OCT). The diagnostic capabilities of OCT parameters were assessed by area under receiver operating characteristic (AUROC) curves. Among all the OCT thickness parameters, no statistical significant difference between NTG group and POAG group was found (all P>0.05). In discriminating NTG or POAG from normal subjects, the average and inferior RNFL thickness, and the minimum GCIPL thickness had better diagnostic capabilities. There was no significant difference in AUROC curve between the best GCIPL thickness parameter (minimum GCIPL) and the best RNFL thickness parameter in discriminating NTG (inferior RNFL; P=0.076) and indiscriminating POAG (average RNFL; P=0.913) from normal eyes. Localized GCIPL loss, especially in the inferior and inferotemporal sectors, is more common in NTG than in POAG. Among all the GCIPL thickness parameters, the minimum GCIPL thickness has the best diagnostic performance in differentiating NTG or POAG from normal subjects, which is comparable to that of the average and inferior RNFL thickness.

Comparison of glaucoma diagnostic ability of ganglion cell-inner plexiform layer according to the range around the fovea

BackgroundTo compare the glaucoma diagnostic ability of the ganglion cell-inner plexiform layer (GCIPL) thickness depending on the range around the fovea using wide-angle, swept-source optical coherence tomography (SS-OCT).MethodsWe compared the glaucoma diagnostic utility of GCIPL parameters across multiple regions while centered on the fovea. In a wide-angle scan, the GCIPL for each 1-mm2 grid square of a 12 × 9 mm2 scan resulted in 108 data points. With respect to the range of the GCIPL measurements around the macula, the wide-angle scan images were classified into three zones. Zone 1 was defined as a narrow area; zone 2 was defined as a mid-sized area; and zone 3 was defined as a wide area. We recorded the quadrant GCIPL thickness, average, and minimum quadrant GCIPL within each zone. The areas under the receiver operating characteristic (AUROCs) curves were calculated to evaluate the glaucoma diagnostic utility.ResultsSixty-one eyes with glaucoma and 59 normal eyes were assessed. The minimum and average GCIPL measurements in zones 1–3 in eyes with glaucoma were significantly lower than those in normal eyes (P < 0.001). The AUROCs for the minimum and inferotemporal GCIPL in zone 1 and the inferotemporal GCIPL thickness in zone 2 were greater than 0.9 (0.945, 0.931, and 0.918, respectively).ConclusionsWide-angle scanning using SS-OCT will contribute to improvements in the detection of glaucomatous damage. The minimum and inferotemporal GCIPL in zone 1 may be more useful for detecting glaucoma than those in the conventional area.

Diagnostic ability of macular ganglion cell asymmetry in Preperimetric Glaucoma

BackgroundTo evaluate the diagnostic ability of macular ganglion cell asymmetry to diagnose preperimetric glaucoma (PPG), using Cirrus spectral domain optical coherence tomography (OCT).MethodsThis prospective study included 67 eyes of 67 patients with PPG and 67 eyes of 67 age- and refractive error-matched controls. We measured circumpapillary RNFL (cpRNFL) thickness, macular ganglion cell-inner plexiform layer (GCIPL) thickness and optic nerve head (ONH) parameters using OCT. Macular ganglion cell asymmetries were expressed as absolute difference and ratios between inferior hemisphere and superior hemisphere, inferotemporal (IT) and superotemporal (ST), IT and superonasal (SN), IT and inferonasal (IN), ST and IN as well as temporal and nasal. An asymmetry index was assigned by taking the absolute value of log10 of the ratio. The area under the receiver operating characteristics curve (AUROC), partial AUROC (pAUROC) ≥ specificities 90 and 95%, cutoff values and sensitivities at specificities 90 and 95% was analyzed.ResultsParameters with largest AUROCs were IT GCIPL thickness (0.784), average RNFL thickness (0.767), and average C/D (0.746). For macular asymmetry parameters, log IT/SN index had the largest AUROC (0.734), followed by log IT/IN index (0.725), and absolute difference of IT−SN GCIPL thickness (0.715). Performance was comparable between the best measures of asymmetry analysis (log IT/SN index) and those of cpRNFL, GCIPL, and ONH parameters (all P > 0.05). The IT/SN asymmetry index not only had the largest pAUROC based on the pAUROCs ≥90 and 95% specificity (0.044 and 0.019) but also had the highest diagnostic sensitivity at 90 and 95% specificities (52.2 and 46.3%).ConclusionsGCIPL asymmetry measurements have diagnostic ability comparable to cpRNFL, GCIPL, and ONH analysis for PPG. The best macular ganglion cell asymmetry parameter was IT/SN asymmetry index, which could be a new parameter to detect early structural changes in PPG.

Diagnostic Abilities of the Optical Microangiography Parameters of the 3×3 mm and 6×6 mm Macular Scans in Glaucoma.

To evaluate the diagnostic abilities of macular vessel length and perfusion densities measured with optical microangiography (OMAG) over a 3×3 mm and a 6×6 mm region, and to compare these with macular ganglion cell-inner plexiform layer (GCIPL) thickness in eyes with primary open-angle glaucoma (POAG). In a cross-sectional study, 96 eyes of 57 control subjects and 88 eyes of 57 POAG patients underwent macular imaging with optical coherence tomography. Area under receiver operating characteristic curves (AUC) and sensitivities at 90% specificity of OMAG and GCIPL parameters were evaluated. Most OMAG parameters of the 3×3 mm macular scan and all inner sector parameters of the 6×6 mm scan were similar (P>0.05) in the POAG and control eyes. All outer sector OMAG parameters of the 6×6 mm scan were significantly less (P<0.05) in the POAG eyes. AUC and sensitivity at 90% specificity of the best parameter of the 3×3 mm OMAG scan (inner temporal vessel length density; 0.65% and 26%, respectively) were statistically similar (P>0.05) to that of the 6×6 mm scan (outer inferior vessel length density; 0.72% and 30%, respectively). AUC and sensitivity of the best GCIPL thickness parameter (inferotemporal GCIPL thickness, 0.84% and 67%) were significantly better (P<0.05) than that of the vessel length densities. The outer sector measurements of the 6×6 mm macular OMAG scans seem to be better than the inner sector measurements in diagnosing glaucoma. The GCIPL thickness measurements were significantly better than all macular OMAG parameters in diagnosing glaucoma.

Vertical Macular Asymmetry Measures Derived From SD-OCT for Detection of Early Glaucoma

PurposeTo test the hypothesis that vertical asymmetry in macular ganglion cell/inner plexiform layer (GCIPL) thickness can improve detection of early glaucoma.MethodsSixty-nine normal eyes and 101 glaucoma eyes had macular imaging with spectral-domain optical coherence tomography (OCT; 200 × 200 cube). The resulting GCIPL thickness matrix was grouped into a 20 × 20 superpixel array and superior superpixels were compared to their inferior counterparts. A global asymmetry index (AI) was defined as the grand mean of the asymmetry ratios. To measure local asymmetry, the corresponding thickness measurements of three rows above and below the horizontal raphe were compared individually and in combinations. Global and local AIs were compared to the best-performing GCIPL thickness parameters with area under the receiver operating curves (AUC) and sensitivity/specificities.ResultsAge or axial length did not influence AIs in normal subjects (P ≥ 0.08). Global and local AIs were significantly higher in the glaucoma group compared to normal eyes. Minimum (AUC = 0.962, 95% confidence interval [CI]: 0.936–0.989) and inferotemporal thickness (AUC = 0.944, 95% CI: 0.910–0.977; P = 0.122) performed best for detection of early glaucoma. The AUC for global AI was 0.851 (95% CI: 0.792–0.909) compared to 0.916 (95% CI: 0.874–0.958) for the best local AI. Combining minimum or inferotemporal GCIPL thickness and the best local AI led to higher partial AUCs (0.088 and 0.085, 90% specificity, P = 0.120 and 0.130, respectively) than GCIPL thickness measures.ConclusionsMacular vertical thickness asymmetry measures did not perform better than sectoral or minimum GCIPL thickness for detection of early glaucoma. Combining local asymmetry parameters with the best sectoral GCIPL thickness measures enhanced this task.

Reproducibility of macular ganglion cell\u2013inner plexiform layer thickness in normal eyes determined by two different OCT scanning protocols

BackgroundTo investigate the reproducibility of macular ganglion cell-inner plexiform layer (GCIPL) thickness measurement in normal eyes determined by different operators and two different raster scanning protocols of Cirrus high-definition optical coherence tomography (HD-OCT).MethodsOne hundred and two eyes of 102 normal subjects were scanned three times using Cirrus HD-OCT with Macular Cube 512 × 128 protocol by two operators, respectively. Three extra scans were obtained using Macular Cube 200 × 200 protocol. The average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal GCIPL thickness was measured. The reproducibility of the measurements was evaluated with intraclass correlation coefficients (ICC) and coefficients of variation (CoV).ResultsThe intra-operator ICCs of macular GCIPL thickness were >0.875; and the inter-operator ICCs were 0.882 to 0.991. The intra-protocol ICCs of Macular Cube 512 × 128 and 200 × 200 protocol were 0.953 to 0.987 and 0.953 to 0.991, respectively; and the inter-protocol ICCs were 0.876 to 0.991. All CoVs were <1.5%.ConclusionsCirrus HD-OCT can measure macular GCIPL thickness in normal eyes with excellent reproducibility. The measurements determined by Macular Cube 512 × 128 and 200 × 200 protocol were highly consistent and both protocols were eligible for macular GCIPL thickness measurement.

Diagnostic Value of Ganglion Cell-Inner Plexiform Layer Thickness in Glaucoma With Superior or Inferior Visual Hemifield Defects.

To determine the diagnostic value of the ganglion cell-inner plexiform layer (GCIPL) thickness in glaucomatous eyes with superior or inferior visual hemifield defects. Eighty-five patients with glaucoma (42 isolated superior hemifield defects and 43 isolated inferior hemifield defects) and 46 normal subjects were enrolled. All patients underwent Cirrus high-definition optical coherence tomography and standard automated perimetry. The area under the receiver operating characteristic curve (AUC) was calculated to determine the diagnostic ability of the GCIPL and peripapillary retinal nerve fiber layer (pRNFL). In the superior hemifield defect glaucoma group, the best parameters for discriminating normal eyes from glaucomatous eyes were the inferotemporal GCIPL thickness (0.942), inferior quadrant RNFL thickness (0.974), and 7 o'clock sector RNFL thickness (0.999). For diagnosing inferior hemifield defect glaucoma, the AUCs of all GCIPL parameters (0.331 to 0.702) were significantly lower than that of the superior quadrant RNFL thickness (0.866, P<0.05). The diagnostic ability of GCIPL parameters was similar to that of the pRNFL parameters in superior hemifield defect glaucoma. However, the diagnostic performance of the GCIPL parameters was significantly inferior to those of the pRNFL parameters in eyes with inferior hemifield defect glaucoma.

Reproducibility of macular ganglion cell-inner plexiform layer measurements using spectral-domain optical coherence tomography

Objective To evaluate the repeatability and reproducibility of macular ganglion cell-inner plexiform layer (GCIPL) thickness measurement using spectral-domain optical coherence tomography (Cirrus HD-OCT).Method One hundred and eight eyes of 54 normal subjects (26 males and 28 females) between 19 and 75 years of age [mean age (46.2± 16.5) years] were included.Each eye underwent macular scanning using Cirrus HD-OCT Macular Cube 512 × 128 protocol by two operators.Three scans of each eye were obtained by each operator.For the right eye of each subject,three extra scans were obtained using Macular Cube 200 × 200 protocol by one operator.The average,minimum,superotemporal,superior,superonasal,inferonasal,inferior,and inferotemporal GCIPL thickness was analyzed and the repeatability of GCIPL thickness measurement was evaluated with intra-operator,inter-operator,intra-protocol,and inter-protocol intraclass correlation coefficients (ICC).Ten extra scans were obtained from the left eyes of 10 randomly selected subjects for reproducibility assessment with coefficients of variation (CV).Results The intra-operator ICC of macular GCIPL measurement using Macular Cube 512 × 128 protocol by two operators were 0.959-0.995 and 0.954-0.997,respectively; and the inter-operator ICC were 0.944-0.993.All intra-and inter operator ICC were ＞0.800 with the highest and lowest records of the average and minimum GCIPL thickness,respectively.The intra-protocol ICC of Macular Cube 512 × 128 protocol and Macular Cube 200× 200 protocol were 0.986-0.996 and 0.927-0.997,respectively; and the inter-protocol ICC were 0.966 0.994.All intra-and inter-protocol ICC were ＞0.800.CV of GCIPL thickness measurement using MacularCube 512×128 protocol were (0.70±0.31)％ (1.35±0.86)％.Conclusion Cirrus HDOCT can measure macular GCIPL thickness in normal eyes with excellent repeatability and reproducibility. Key words: Macula lutea/anatomy & histology; Retinal ganglion cells; Tomography, optical coherence; Reproducibility of results

Comparative Study of Macular Ganglion Cell–Inner Plexiform Layer and Peripapillary Retinal Nerve Fiber Layer Measurement: Structure–Function Analysis

We explored and compared the relationships between the visual field (VF) sensitivities assessed by standard automated perimetry (SAP), and the ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses as measured by Cirrus high-definition optical coherence tomography (HD-OCT) in glaucomatous eyes. We enrolled 213 eyes of 213 patients with glaucoma. The thicknesses of the average/sectoral GCIPL and pRNFL were measured by Cirrus HD-OCT. The mean sensitivity (MS) of 24-2 SAP was recorded on decibel and 1/L scales. The topographic relationships between structure and function were investigated. Statistically significant correlations between the corresponding VF sensitivity and the macular GCIPL thickness were found in all GCIPL sectors. Among six GCIPL sectors, the strongest association was observed between superonasal center MS and inferotemporal GCIPL thickness. In comparative analysis, the association between the central cluster MS and average GCIPL thickness was significantly stronger than that of temporal pRNFL thickness using the decibel scale (P < 0.001). The association between regional VF sensitivities, and the inferior hemifield and inferior GCIPL thicknesses were significantly stronger than those of the corresponding pRNFL thickness using the decibel scale (P = 0.001 and 0.007). The average and sectoral GCIPL thicknesses determined by Cirrus HD-OCT were associated significantly with global and regional VF sensitivity in patients with glaucoma. The macular GCIPL thickness values may provide more valuable information than temporal pRNFL thickness values for understanding the structure-function relationships of the macular region.