Optical coherence tomography angiography findings of an optic disc melanocytoma in a glaucoma eye.

PURPOSE: To determine the optical coherence tomography angiography (OCTA) characteristics of a case of optic disc melanocytoma (ODM) associated with glaucomatous visual field and retinal nerve fiber layer (RNFL) defects in normal tension glaucoma. METHODS: The left eye of a 37-year-old female patient followed for a stable ODM for 10 years was investigated with OCT, OCTA, fluorescein (FA), and indocyanine green (ICGA) angiography. The ODM was unchanged, but a previously unknown inferotemporal neuroretinal rim loss and inferotemporal and superotemporal wedge shape glaucomatous RNFL thinning were seen with corresponding glaucomatous visual field defects. The intraocular pressure was 12 mmHg without treatment. RESULTS: In the area of the ODM, FA showed minimal vasculature, and week staining in the late phase, while ICGA showed no signal. In contrast, OCTA showed a dense vasculature in both the superficial and deep layers of the melanocytoma, which was clearly separated from the capillaries of the peripapillary retina. OCTA also showed reduced peripapillary perfusion in the areas of the glaucomatous RNFL bundle defects. CONCLUSIONS: In the presented case of a stable ODM and newly detected normal tension glaucoma, OCTA provided more information on perfusion than FA and ICGA which are limited by the heavy pigmentation of the ODM. OCTA also showed a similarly decreased capillary perfusion in both RNFL bundle defects suggesting that the structural damage was related to glaucoma and not compression by ODM. These results suggest that OCTA may be a method preferred over conventional angiography in ODM cases.

Circumpapillary microperimetry to detect glaucoma: a pilot study for sector-based comparison to circumpapillary retinal nerve fiber layer measurement.

PURPOSE: To evaluate and compare the diagnostic performance of circumpapillary microperimetry (MP) sensitivity and circumpapillary retinal nerve fiber layer thickness (cpRNFLT) measured with optical coherence tomography (OCT) for detection of early to moderate open-angle glaucoma. METHODS: Eleven eyes (11 patients) with early or moderate open-angle glaucoma and seven normal eyes (7 subjects) underwent MP (MP-3 microperimeter, NIDEK, Japan) and cpRNFLT measurement (RS-3000 Advance OCT, NIDEK, Japan) using an identical circumpapillary circle and similar measurement sectors. The structure-function relationship and the area under the receiver-operating characteristics curve (AUROC) were investigated for each sector, respectively. RESULTS: Significant differences (P < 0.05) between glaucoma and normal eyes were found for five of the 12 OCT sectors and seven of the 24 MP sectors. High correlation between cpRNFLT and MP sensitivity was found in the inferotemporal area (OCT sector 5) and superotemporal area (OCT sector 1) (r = 0.818, P < 0.001, and r = 0.796, P < 0.001, respectively). The AUROC values in these sectors ranged 0.890-1.000 for cpRNFLT and 0.825-0.981 for MP sensitivity. Overall, the AUROC ranged 0.506-1.000 for sector cpRNFLT and 0.591-0.981 for sector MP sensitivity. CONCLUSIONS: In this pilot study, circumpapillary MP sensitivity and cpRNFLT showed similar diagnostic power. The structure-function relationship was strong for the superotemporal and inferotemporal circumpapillary areas. Our results suggest that circumpapillary MP represents a new aspect of microperimetry in glaucoma. Further studies on larger populations are necessary to clarify whether the current results are confirmed in clinical practice.

Preserved retinal sensitivity in spatial correspondence to an intrachoroidal cavitation area with full thickness retinal defect: a case report.

BACKGROUND: Intrachoroidal cavitation (ICC) in the temporal peripapillary area is a relatively frequent finding in high myopia. However, ICC associated with a full thickness retinal defect rarely observed. We report an unusual case of ICC combined with a full thickness retinal defect in the papillo-macular bundle, in which the spatially corresponding visual field sensitivity was preserved. CASE PRESENTATION: A high myopic and pseudophakic left eye of a 79-year-old Japanese woman was evaluated with swept source optical coherence tomography (SS-OCT) and Humphrey 30-2 visual field testing for moderate glaucoma. The best-corrected visual acuity was 20/20, the axial length was 28.77 mm, the mean deviation -8.94 dB, and the intraocular pressure was 15 mmHg without medication. The horizontal SS-OCT scans showed a wide ICC with a full thickness retinal defect in the papillo-macular area at the outer border of the myopic peripapillary beta zone atrophy. The retina was herniated into the ICC area. While no sensitivity loss was seen in the central visual field corresponding to the full thickness retinal defect, a glaucomatous visual field deterioration spatially corresponding to the glaucomatous disc damage was present. The preserved retinal sensitivity spatially corresponding to the full thickness retinal defect was confirmed with microperimetry. CONCLUSIONS: Our case suggests that retina herniated in peripapillary ICC temporal to the disc may preserve some function despite the presence of a retinal defect.

Effect of high myopia on glaucoma diagnostic parameters measured with optical coherence tomography.

BACKGROUND: We examined the influence of high myopia on conventional spectral-domain optical coherence tomographic parameters and assessed the macular ganglion cell complex thickness to macular outer retinal thickness ratio as a new optical coherence tomography parameter. DESIGN: Prospective cross-sectional study. PARTICIPANTS: Sixty normal and 30 highly myopic eyes (refractive error more than -6 D). METHODS: We used the RTVue-100 to measure macular ganglion cell complex and circumpapillary retinal nerve fibre layer thickness, global loss volume, and focal loss volume and then calculated the ganglion cell complex thickness to macular outer retinal thickness ratio. MAIN OUTCOME MEASURES: Each parameter was compared between the two groups. Using the area under receiver operating characteristics curve, the classification abilities of optical coherence tomography parameters were examined in highly myopic eyes. RESULTS: Between normal and highly myopic eyes, we found significant differences in ganglion cell complex and retinal nerve fibre layer thickness, global loss volume and focal loss volume. The new ratio parameter was not significantly different between groups (55.74% vs. 54.50%). The area under receiver operating characteristics curve was 0.775 (P < 0.01) for retinal nerve fibre layer thickness, 0.721 (P < 0.01) for ganglion cell complex thickness and 0.588 (P > 0.05) for the new ratio parameter. CONCLUSIONS: Although refractive status significantly affected conventional optical coherence tomography parameters, the new ratio parameter may not be influenced by refractive error. Therefore, a normative database for healthy highly myopic eyes may not be necessary if ratio parameter is used.

Relationship between macular ganglion cell complex thickness and macular outer retinal thickness: a spectral-domain optical coherence tomography study.

BACKGROUND: To assess the relationship between macular ganglion cell complex and macular outer retinal thicknesses. DESIGN: Case-control study. PARTICIPANTS: Forty-two normal eyes and 91 eyes with primary open-angle glaucoma were studied. METHODS: Spectral-domain optical coherence tomography (RTVue-100) was used to measure the macular ganglion cell complex and macular outer retinal thickness. Ganglion cell complex to outer retinal thickness ratio was also calculated. MAIN OUTCOME MEASURES: The relationships between the ganglion cell complex and outer retinal thicknesses and between the ganglion cell complex to outer retinal thickness ratio and outer retinal thickness were evaluated. RESULTS: There was a positive correlation between ganglion cell complex and outer retinal thicknesses in the normal group and the glaucoma group (r = 0.53, P < 0.001 and r = 0.42, P < 0.001, respectively). In that respect, there was no correlation between ganglion cell complex to outer retinal thickness ratio and outer retinal thickness in the both groups (r = -0.07, P = 0.657, and r = 0.04, P = 0.677, respectively). The ganglion cell complex to outer retinal thickness ratio was 55.65% in the normal group, 45.07% in the glaucoma group. This difference was statistically significant. CONCLUSIONS: The ganglion cell complex thickness may be affected by outer retinal thickness, and there is individual variation in the outer retinal thickness. Therefore, when determining the ganglion cell complex, it seems necessary to consider the outer retinal thickness as well. We propose the ratio as a suitable parameter to account for individual variations in outer retinal thickness.

Influence of Refractive Error on Circumpapillary Structure-Function Versus Vessel Density-Function Relationships in Open Angle Glaucoma.

PRCIS: In Japanese open angle glaucoma (OAG) eyes correlation of 30-degree visual field mean deviation (MD) and visual field index (VFI) with circumpapillary vessel density is systematically stronger than that with circumpapillary retinal nerve fiber layer thickness (RNFLT), and is preserved in myopia and high myopia. PURPOSE: The purpose of this study was to investigate the influence of refractive error on the relationship between circumpapillary retinal nerve fiber layer thickness (cpRNFLT) and circumpapillary vessel density (cpVD), respectively, and global visual field parameters in Japanese open angle glaucoma (OAG) eyes. MATERIAL AND METHODS: One eye of 81 Japanese OAG patients (spherical equivalent refractive error: +3.0 to -9.0 D) underwent 360-degree cpRNFLT and cpVD measurements with Cirrus HD 5000-AngioPlex optical coherence tomography and 30-2 Humphrey visual field testing for mean deviation (MD) and visual field index (VFI) within 1 month. Correlations were determined for the whole population and each refractive error subgroups, separately: emmetropia/hyperopia (n=24), mild (n=18), moderate (n=20), and high myopia (n=19). RESULTS: For the total population, significant strong to very strong correlations were found between MD, VFI, and both cpRNFLT and cpVD, respectively, with consistently higher r -values for cpVD (highest r -values: 0.532 for cpRNFLT, P <0.001; 0.722 for cpVD, P <0.001). Of the refractive subgroups, statistically significant correlations between cpRNFLT and the visual field parameters were maintained only in the hyperopia/emmetropia and moderate myopia groups. In contrast, statistically significant, strong to very strong correlations between cpVD and both MD and VFI, always exceeding the corresponding r -values found for cpRNFLT were found in all refractive subgroups, with r -values ranging between 0.548 ( P =0.005) and 0.841 ( P <0.001). CONCLUSIONS: Our results suggest that in Japanese OAG eyes the relationship of MD and VFI with cpVD is strong. It is systematically stronger than that with cpRNFLT and preserved in each conventional refractive error category including high myopia.

Effect of Topical Pilocarpine Instilled Before Laser Peripheral Iridotomy on Regional Iris Thickness in Primary Angle Closure Disease: A Swept-Source Anterior Segment Optical Coherence Tomography Pilot Study.

PURPOSE: To determine whether the temporal-superior or the nasal-superior iris area becomes thinner (more optimal) for laser peripheral iridotomy (LPI) after pilocarpine instillation in primary angle closure disease (PACD); and to identify an angle for optimal penetration of the laser beam. PATIENTS AND METHODS: Iris thickness at 2 mm from the iris root in the preset scanning axes was measured using swept-source anterior segment optical coherence tomography before and 60 minutes after the instillation of pilocarpine 2% in one eye of 30 consecutive Japanese PACD patients with thick, dark brown iris. Iris thickness at 1:30 and 10:30 clock hour positions were evaluated in sagittal and oblique directions, resulting sagittal iris thickness (SIT) and minimum iris thickness (MIT) parameters, respectively. RESULTS: Compared to the baseline values, iris thickness decreased significantly (P < .001) in both locations after pilocarpine instillation. Both before and after pilocarpine instillation the temporal-superior iris thickness was significantly smaller than the nasal-superior thickness (P ≤ .001). After pilocarpine instillation, the temporal-superior iris was significantly thinner in an approximately 13° angle direction temporal to the sagittal direction than in the sagittal direction (MIT: 0.322 mm; SIT: 0.346 mm, P < .001). CONCLUSIONS: After pilocarpine instillation, the temporal-superior iris and an approximately 13° angle temporal to the sagittal direction may provide an optimal location and laser beam angle for LPI in PACD eyes.

Myopic Peripapillary Pits with Spatially Corresponding Localized Visual Field Defects: A Progressive Japanese and a Cross-Sectional European Case.

We report 2 peripapillary pit cases, in which the isolated visual field defects spatially correspond to the pit-related retinal nerve fiber layer and optical coherence tomography (OCT) angiography (OCTA) perfusion damage areas. A high myopic eye of a 39-year-old Japanese male patient, and a moderate myopic eye of a 47-years old Caucasian female patient were evaluated with OCT, OCTA, and visual field testing for peripapillary pits and spatially corresponding localized visual field defects. In the Japanese patient a temporal and in the Caucasian patient an inferotemporal peripapillary pit was confirmed, both spatially associated with a myopic peripapillary atrophy area. In both cases, the retinal nerve fibers herniated into the pit. En face OCT and OCTA revealed retinal nerve fiber bundle defects and reduced vessel density in the corresponding areas, both projecting to the pit. The visual field showed localized scotomas spatially corresponding to the nerve fiber bundle/OCTA defects in both patients. The visual field defect was a progressing (extending and deepening) paracentral scotoma in the Japanese patient, and a localized superior paracentral and superior arcuate scotoma in the Caucasian patient. Our cases show that peripapillary pits occurring in both Japanese and white European eyes can cause localized retinal nerve fiber bundle and OCTA damage and visual field defects of which some can worsen during the follow-up. To separate scotomas due to peripapillary pits and glaucoma is therefore of clinical importance and requires special attention from ophthalmologists.

RETeval Portable Electroretinogram Parameters in Different Severity Stages of Glaucoma.

PRéCIS:: Four parameters of the noninvasive, portable RETeval electroretinogram (ERG) system were found to correlate with visual field mean deviation and optical coherence tomography (OCT) thickness parameters, and may therefore be suitable for glaucoma detection. PURPOSE: To investigate the RETeval full-field ERG parameters for accuracy of separating glaucoma and normal eyes, and correlation with glaucoma severity. PATIENTS AND METHODS: Sixty-two eyes of 62 primary open-angle glaucoma patients [visual field mean deviation (MD) range: -0.44 to -31.15 dB] and 39 eyes of 39 healthy controls underwent one RETeval test (photopic negative response protocol), OCT imaging, and Humphrey 30-2 visual field testing. The glaucoma patients were divided into early (MD≥-6dB, n=33) and moderate-to-advanced (MD<-6 dB, n=29) groups. RESULTS: Significant correlations were found between the best-performing 4 RETeval ERG parameters and the glaucoma severity measures (MD and OCT thickness parameters) for all eyes, all glaucoma eyes and the moderate-to-advanced glaucoma eyes [photopic negative response amplitude at 72 ms (PhNR 72) and MD: r=-0.333, -0.414, and -0.485, respectively, P≤0.008; PhNR 72 and average circumpapillary retinal nerve fiber layer thickness; r=-0.429, -0.450, and -0.542, respectively, P≤0.002]. Except for P-ratio, there was no significant difference between the area under the receiver-operating characteristic (AUROC) values of the OCT thickness parameters (range: 0.927 to 0.938) and the 4 best-performing RETeval ERG parameters (range: 0.839 to 0.905) in the early glaucoma versus control separation. For differentiating the control and the moderate-to-advanced glaucoma eyes, the AUROC values of the 4 best-performing RETeval ERG parameters ranged between 0.924 and 0.958, and no significant difference was found between them and those of the OCT parameters. CONCLUSIONS: The noninvasive, portable RETeval full-field ERG device may be useful to detect glaucoma in moderate-to-advanced stages.

Circumpapillary structure-function relationships with microperimetry and spectral domain optical coherence tomography in glaucoma: a pilot study.

PURPOSE: To compare the relationships between circumpapillary microperimetry (MP)-sensitivity measurements and various circumpapillary retinal thickness parameters in healthy and primary open-angle glaucoma (POAG) eyes. METHODS: In 14 eyes of 14 healthy subjects and 22 early-moderate POAG eyes of 22 patients, circumpapillary optical coherence tomography thickness measurements (RS-3000 Advance OCT, NIDEK) of the retinal nerve fiber layer (cpRNFL), total retina (cpTR), and ganglion cell complex (cpGCC) and outer retina (cpOR) and circumpapillary MP-sensitivity measurements (MP-3 microperimeter, NIDEK) were made in 12 sectors of identical circumpapillary circles. The structure-function relationship was investigated in each sector. RESULTS: Statistically significant correlations with circumpapillary MP-sensitivity values were found for cpRNFL in five sectors, cpTR in nine sectors, cpGCC in nine sectors, and cpOR in three sectors. The structure-function relationship was strong (r=0.4-0.69) in three sectors for cpRNFL, in six for cpTR, in four for cpGCC, and in one for cpOR. The relationship was very strong (r>0.7) in one sector for cpRNFL, cpTR, and cpGCC, and in no sectors for cpOR. The very strong relationships all occurred in sector 5 (inferotemporal sector). CONCLUSION: In our pilot study, the circumpapillary structure-function relationship was more extensive for cpTR thickness and cpGCC thickness than for cpRNFL thickness, which suggests that the former parameters may require greater attention in structure-function research into glaucoma.

Circumpapillary ganglion cell complex thickness to diagnose glaucoma: A pilot study.

PURPOSE: The purpose of this study is to evaluate the applicability of a new optical coherence tomography parameter, the circumpapillary ganglion cell complex (cpGCC) thickness for glaucoma diagnostics. SUBJECTS AND METHODS: The RS-3000 Advance SD-OCT (NIDEK, Aichi, Japan) was used to measure global and sector macular GCC (mGCC) thickness, circumpapillary retinal nerve fiber layer (cpRNFL) thickness, cpGCC, and circumpapillary total retina (cpTR) thickness in 1 eye of 48 preperimetric/early perimetric primary open-angle glaucoma patients and 28 healthy Japanese participants. Area under the receiver-operating characteristic (AUROC) curves were used for between-method comparisons. RESULTS: All global and sector parameters except for the nasal sector differed significantly between the patient groups (P ≤ 0.009). The AUROC for global mGCC (0.917) was significantly higher (P < 0.01) than that for global cpRNFL (0.760), global cpGCC (0.828), and global cpTR (0.812). The AUROC values of global and temporal cpGCC were significantly higher than those of the corresponding cpRNFL parameters (P < 0.05). Correlation between the visual field means deviation and each of the global thickness parameters was similar (r: 0.418-0.473, P< 0.001). At >90% specificity, the cpGCC, cpTR, and cpRNFL were able to detect 4%, 10%, and 0% of glaucoma eyes that were not detected by the mGCC thickness. CONCLUSIONS: In Japanese eyes, the diagnostic accuracy of cpGCC is lower than that of mGCC but higher than that of cpRNFL. Our results suggest that the use of cpGCC may not improve glaucoma diagnostics when there is no macular disease but may be of benefit when macular diseases prevent successful mGCC measurements.

Changes in the size of the foveal avascular zone after vitrectomy with internal limiting membrane peeling for a macular hole.

PURPOSE: To determine the size of the foveal avascular zone (FAZ) before and after vitrectomy for a macular hole (MH). STUDY DESIGN: Retrospective case series study. METHODS: Twenty-five eyes of 25 patients with a unilateral MH that had undergone vitrectomy with internal limiting membrane peeling were studied. The unaffected 17 fellow eyes were studied in the same way. En face images of the parafoveal region were obtained by optical coherence tomography angiography, and the images were used to measure the FAZ before and 1 month after the vitrectomy. The relationships between the different FAZ sizes and the ocular parameters were determined by Pearson product moment correlation analysis. RESULTS: Compared with the preoperative superficial FAZ (sFAZ), the postoperative sFAZ was significantly reduced (P < 0.001). The postoperative sFAZ was significantly smaller than that of the fellow eye (P < 0.001). The size of the postoperative sFAZ was significantly correlated with that of the preoperative sFAZ, the postoperative foveal thickness (FT), and the sFAZ of the fellow eyes (r = 0.520, P = 0.008; r = -0.515, P = 0.012; and r = 0.702, P = 0.002, respectively). The size of the postoperative deep FAZ (dFAZ) was significantly correlated with the postoperative FT and the dFAZ of the fellow eyes (r = -0.441, P = 0.035; and r = 0.499, P = 0.049, respectively). However, no significant correlation was found between the size of the postoperative FAZ and the size of the preoperative MH. CONCLUSIONS: MH closure leads to a significant decrease in the size of the FAZ symmetrical to the size of the fellow eye. The size of the postoperative FAZ is influenced by the postoperative FT independently of the size of the MH.

The clinical utility of measuring the macular outer retinal thickness in patients with glaucoma.

PURPOSE: Few optical coherence tomography (OCT) studies have investigated outer retinal thickness including the photoreceptor layer in glaucoma. We measured changes in the macular outer retinal thicknesses using OCT in patients with glaucoma with an average follow-up of 2.9 ± 0.8 years. METHODS: A total of 39 eyes of 39 patients with primary open-angle glaucoma were analyzed. The RTVue-100 was used to measure the macular outer retinal, macular ganglion cell complex, and circumpapillary retinal nerve fiber layer thicknesses, global loss volume, and focal loss volume. Using the paired t test, baseline parameters were compared with those at the last follow-up. RESULTS: The average baseline mean deviation value in the Humphrey Field Analyzer was -2.13 dB. The ganglion cell complex thickness significantly decreased over the follow-up period (baseline thickness, 79.66 ± 7.71 µm; final thickness, 76.79 ± 7.39 µm; p<0.001). There were significant differences between baseline and final visit measurements for circumpapillary retinal nerve fiber layer thickness, global loss volume, and focal loss volume (p<0.001, p<0.001, and p = 0.004, respectively). However, there was no significant change in outer retinal thickness (baseline thickness, 167.56 ± 7.26 µm; final thickness, 167.25 ± 7.93 µm; p = 0.540). CONCLUSIONS: Outer retinal thickness was not altered during the follow-up period. The stability of outer retinal thickness may indicate the reliability of OCT analysis for glaucoma follow-up.

Differences of Intrasession Reproducibility of Circumpapillary Total Retinal Thickness and Circumpapillary Retinal Nerve Fiber Layer Thickness Measurements Made with the RS-3000 Optical Coherence Tomograph.

PURPOSE: To evaluate the intrasession reproducibility of various thickness parameters used to diagnose and follow-up glaucoma, in particular circumpapillary total retinal thickness (cpTR) provided by the RS-3000 optical coherence tomograph (OCT). METHODS: Fifty-three healthy eyes of 28 subjects underwent three consecutive imaging with the RS-3000 Advance OCT (NIDEK, Aichi,Japan) to evaluate the intrasession reproducibility of circumpapillary total retinal thickness (cpTR), circumpapillary retinal nerve fiber layer thickness (cpRNFL), macular ganglion cell complex thickness (mGCC) and macular total retina thickness (mTR) measurements. Intraclass correlation (ICC), coefficient of variation (CV) and reproducibility coefficient (RC) were calculated for each parameter. RESULTS: The ICC and CV values for mean cpTR and cpRNFL were 0.987 and 0.897, and 0.60% and 2.81%, respectively. The RC values for the mean cpTR and cpRNFL were 5.95 µm and 9.04 µm, respectively. For all cpTR parameters the ICC values were higher and both the CV and RC values were lower than those for the corresponding cpRNFL parameters. The ICC and CV values for superior mGCC, inferior mGCC, superior mTR and inferior mTR were 0.983, 0.980, 0.983 and 0.988, and 0.84%, 0.98%, 0.48% and 0.43%, respectively. The RC values for superior mGCC, inferior mGCC, superior mTR and inferior mTR were 2.86 µm, 3.12 µm, 4.41 µm and 4.43 µm, respectively. CONCLUSIONS: Intrasession reproducibility of cpTR, mGCC and mTR measurements made on healthy eyes was high. Repeatability of cpTR measurements was better than that of the corresponding cpRNFL measurements. These results suggest that future clinical investigations addressing detection of glaucoma and glaucomatous progression with the RS-3000 OCT may benefit from focusing on the cpTR parameters.

Influence of axial length on ganglion cell complex (GCC) thickness and on GCC thickness to retinal thickness ratios in young adults.

PURPOSE: The present study was designed to investigate the influence of axial length on macular ganglion cell complex (GCC) thickness and two ratio parameters-the GCC thickness to macular total retinal thickness (G/T) ratio and the GCC thickness to macular outer retinal thickness (G/O) ratio-using spectral-domain optical coherence tomography (OCT). METHODS: In this prospective case series, 74 eyes of 74 healthy Japanese study participants with varying degrees of myopia were recruited. GCC, outer retinal, and total retinal thicknesses were measured with the RTVue-100 system. The G/T and G/O ratios were also calculated. The axial length was determined using the IOLMaster. The correlation between the OCT measurements and axial length was evaluated. RESULTS: The average axial length was 25.05 ± 1.38 mm. The GCC thickness was significantly correlated with axial length (r = -0.384, P = 0.001). The outer retinal thickness and the total retinal thickness were significantly correlated with axial length (r = -0.444, P < 0.001 and r = -0.493, P < 0.001, respectively), but the G/T and G/O ratios were not (r = -0.093, P = 0.428 and r = -0.091, P = 0.440, respectively). CONCLUSIONS: GCC thickness is affected by axial length. Because the prevalence of myopia is high in Japan, when determining the GCC thickness of Japanese individuals, it seems necessary to consider the axial length as well. To take account of individual variation in axial length, we propose the ratio parameters as a suitable parameter.

Comparison of macular ganglion cell complex thickness to total retinal thickness ratio between Hungarian and Japanese eyes.

PURPOSE: To compare macular ganglion cell complex (GCC) thickness to total retinal thickness (G/T) ratio and the potential influence of race, age, macular outer retinal (OR) thickness, refractive error, intraocular pressure (IOP), mean deviation (MD) and disc area on GCC thickness between healthy European Caucasian and Japanese subjects. METHODS: GCC, OR and total retinal thickness were measured with the RTVue-100 Fourier-domain optical coherence tomograph (OCT) in one eye of 102 healthy subjects (52 Hungarian and 50 Japanese) 24-80 years of age. The χ (2) test, analysis of covariance and multiple regression analysis were used. RESULTS: There was no significant difference in average, superior and inferior GCC thickness and G/T ratio between the two ethnic groups (P > 0.05 for all comparisons). In the Japanese eyes, a significant positive relationship between GCC thickness and OR thickness was found (P < 0.001). This was not seen in the Hungarian eyes (P = 0.07). No significant relationship between GCC thickness and age, refractive error, IOP, MD or disc area was found for either group. CONCLUSIONS: GCC thickness and G/T ratio do not differ between healthy Hungarian and Japanese eyes. In contrast, the difference found for the relationship of GCC and OR between Japanese and Hungarian eyes suggests that in the macular retina there are ethnically related differences that need to be considered when any new macular OCT parameter is proposed for the diagnosis of glaucoma.

Ability of optical coherence tomography-determined ganglion cell complex thickness to total retinal thickness ratio to diagnose glaucoma.

PURPOSE: To evaluate the usefulness of the spectral-domain optical coherence tomography (SD OCT)-determined ganglion cell complex thickness to total retinal thickness ratio (G/T ratio) in diagnosing glaucoma. METHODS: A total of 99 eyes with primary open-angle glaucoma and 35 normal eyes were enrolled in the study. SD OCT (RTVue-100) was used to measure the macular ganglion cell complex thickness, total retinal thickness, outer retinal thickness, and circumpapillary retinal nerve fiber layer (RNFL) thickness. A new macular parameter, the G/T ratio, was also calculated. The ability of each parameter to diagnose glaucoma was examined by analyzing the area under the receiver operating characteristics curve (AUROC) and the sensitivity at fixed specificity. RESULTS: The G/T ratio was 36.0 ± 1.5% in normal eyes, 31.8 ± 1.7% in early glaucoma, and 30.2 ± 2.6% in advanced glaucoma. These decreases in the ratio were statistically significant. For the AUROC, the individual SD OCT parameters were 0.982 for the G/T ratio, 0.968 for the macular ganglion cell complex thickness, 0.942 for the RNFL thickness, and 0.841 for the total retinal thickness. The AUROC for the G/T ratio was significantly higher than that seen for the total retinal and RNFL thicknesses (P<0.05). Analyses of the sensitivity at a specificity of >90% indicated that the G/T ratio (sensitivity, 93.94%) was the best diagnostic parameter. CONCLUSIONS: Decreases in the G/T ratio occur during the early stages of glaucoma. When using SD OCT to diagnose glaucoma, the G/T ratio may improve the diagnostic ability of the macular parameter.

Glaucomatous eye macular ganglion cell complex thickness and its relation to temporal circumpapillary retinal nerve fiber layer thickness.

PURPOSE: To clarify the correlation between temporal circumpapillary retinal nerve fiber layer (RNFL) thickness and macular ganglion cell complex (mGCC) thickness in glaucomatous eyes. METHODS: Seventy-seven eyes of 77 subjects were categorized as normal, early glaucoma and moderate-to-advanced (moderate) glaucoma. After the circumpapillary RNFL thickness and mGCC thickness were measured, the temporal mean RNFL and mean mGCC were compared within the three groups. The study also investigated whether there was any correlation between the temporal RNFL and mGCC thicknesses. RESULTS: In the glaucoma groups, significant thinning of the temporal RNFL and mGCC thicknesses was noted. With the exception of the papillomacular bundle (r = -0.078), correlations were seen in each of the early glaucoma mGCC and temporal RNFL sectors (r = 0.38-0.753). Correlations were also noted for the mGCC and all temporal RNFL sectors in the moderate glaucoma group (r = 0.425-0.809). CONCLUSIONS: From the early stage of glaucoma, similar decreases of the mGCC and RNFL occured, and a high correlation existed between the two. Therefore, like RNFL, mGCC can potentially be used to detect the early stages of glaucoma. However, in early glaucoma eyes, the papillomacular bundle of the RNFL may be spared, even though mGCC thinning is present.