Correlation between cognitive impairment and retinal neural loss assessed by swept-source optical coherence tomography in patients with mild cognitive impairment.

INTRODUCTION: We compared peripapillary retinal nerve fiber layer and macular thickness measurements in patients with mild cognitive impairment (MCI) and control subjects using swept-source optical coherence tomography (SS-OCT). We also assessed the relationship between SS-OCT measurements and the severity of cognitive impairment. METHODS: Peripapillary retinal nerve fiber layer and macular thickness were measured in 23 patients and 24 control subjects using SS-OCT. Cognitive status was assessed using the Mini-Mental State Examination, the Montreal Cognitive Assessment, and the Pfeffer Questionnaire. RESULTS: Most inner retinal layer thickness parameters were significantly smaller in patients with MCI, especially macular ganglion cell complex thickness measurements. Mini-Mental State Examination and Montreal Cognitive Assessment findings were significantly correlated with most macular thickness parameters. DISCUSSION: The SS-OCT-measured inner retinal layers of patients with MCI displayed thinning, especially in the central macular area. SS-OCT technology can provide useful information on ocular involvement patterns and holds promise as an ocular biomarker in this patient population.

Evaluation of inner retinal layers in eyes with temporal hemianopic visual loss from chiasmal compression using optical coherence tomography.

PURPOSE: We measured macular inner retinal layer thicknesses using frequency-domain optical coherence tomography (fd-OCT) and correlated these measures with visual field (VF) in eyes with temporal hemianopia from chiasmal compression and band atrophy (BA) of the optic nerve. METHODS: Macular fd-OCT scans and VFs were obtained from 33 eyes of 33 patients with temporal hemianopia and 36 control eyes. The macular retinal nerve fiber layer (mRNFL), combined retinal ganglion cell and inner plexiform layers (RGCL+), and the inner nuclear layer (INL) were segmented. Measurements were averaged for each macula quadrant. Scans were assessed qualitatively for microcysts in the INL. The VF was estimated from the central 16 test points. The two groups were compared. Correlations between VF and OCT measurements were assessed. RESULTS: The mRNFL, RGCL+, and total retinal (TR) macular thickness measurements were significantly smaller in BA eyes than controls. In the nasal quadrants, INL measurements were significantly greater in BA eyes than controls. The mRNFL and RGCL+ measurements had greater discrimination ability than TR measurements in the temporal quadrants. A significant correlation was found between most OCT parameters and their corresponding VF parameters. The strongest association was observed between RNFL and RGCL+ thickness, and VF loss in the corresponding area. The INL microcysts were found in seven eyes with BA, but not in controls. CONCLUSIONS: Band atrophy leads to mRNFL and RGCL+ thinning, and INL thickening, and mRNFL and RGCL+ measurements are correlated strongly with VF loss. Segmented macular thickness measurements may be useful for quantifying neuronal loss in chiasmal compression.

Relationship between optical coherence tomography, pattern electroretinogram and automated perimetry in eyes with temporal hemianopia from chiasmal compression.

PURPOSE: To evaluate the relationship between pattern electroretinogram (PERG) amplitude, macular and retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT), and visual field (VF) loss on standard automated perimetry (SAP) in eyes with temporal hemianopia from chiasmal compression. METHODS: Forty-one eyes from 41 patients with permanent temporal VF defects from chiasmal compression and 41 healthy subjects underwent transient full-field and hemifield (temporal or nasal) stimulation PERG, SAP and time domain-OCT macular and RNFL thickness measurements. Comparisons were made using Student's t-test. Deviation from normal VF sensitivity for the central 18 degrees of VF was expressed in 1/Lambert units. Correlations between measurements were verified by linear regression analysis. RESULTS: PERG and OCT measurements were significantly lower in eyes with temporal hemianopia than in normal eyes. A significant correlation was found between VF sensitivity loss and full-field or nasal, but not temporal, hemifield PERG amplitude. Likewise a significant correlation was found between VF sensitivity loss and most OCT parameters. No significant correlation was observed between OCT and PERG parameters, except for nasal hemifield amplitude. A significant correlation was observed between several macular and RNFL thickness parameters. CONCLUSIONS: In patients with chiasmal compression, PERG amplitude and OCT thickness measurements were significant related to VF loss, but not to each other. OCT and PERG quantify neuronal loss differently, but both technologies are useful in understanding structure-function relationship in patients with chiasmal compression. (ClinicalTrials.gov number, NCT00553761).

Comparison of Fourier-domain and time-domain optical coherence tomography in the detection of band atrophy of the optic nerve.

PURPOSE: To compare the ability of Fourier-domain (FD) optical coherence tomography (3D OCT-1000; Topcon, Tokyo, Japan) and time-domain (TD) OCT (Stratus; Carl Zeiss Meditec Inc, Dublin, California, USA) to detect axonal loss in eyes with band atrophy (BA) of the optic nerve. DESIGN: Cross-sectional study. METHODS: Thirty-six eyes from 36 patients with BA and temporal visual field (VF) defect from chiasmal compression and 36 normal eyes were studied. Subjects were submitted to standard automated perimetry and macular and retinal nerve fiber layer (RNFL) measurements were taken using 3D OCT-1000 and Stratus OCT. Receiver operating characteristic (ROC) curves were calculated for each parameter. Spearman correlation coefficients were obtained to evaluate the relationship between RNFL and macular thickness parameters and severity of VF loss. Measurements from the two devices were compared. RESULTS: Regardless of OCT device, all RNFL and macular thickness parameters were significantly lower in eyes with BA compared with normal eyes, but no statistically significant difference was found with regard to the area under the ROC curve. Structure-function relationships were also similar for the two devices. In both groups, RNFL and macular thickness measurements were generally and in some cases significantly smaller with 3D OCT-1000 than with Stratus OCT. CONCLUSIONS: The introduction of FD technology did not lead to better discrimination ability for detecting BA of the optic nerve compared with TD technology when using the software currently provided by the manufacturer. 3D OCT-1000 FD OCT RNFL and macular measurements were generally smaller than TD Stratus OCT measurements. Investigators should be aware of this fact when comparing measurements obtained with these two devices.