Macular ganglion cell layer imaging in preperimetric glaucoma with speckle noise-reduced spectral domain optical coherence tomography.

OBJECTIVE: To visualize the macular ganglion cell layer (GCL) and measure its thickness in normal eyes and eyes with preperimetric glaucoma, using speckle noise-reduced spectral domain optical coherence tomography (SD-OCT). DESIGN: Retrospective consecutive case series. PARTICIPANTS: Thirty-seven eyes of 37 patients with preperimetric glaucoma and 39 normal eyes of 39 volunteers. METHODS: Vertical and horizontal SD-OCT B-scan images were acquired with minimal speckle noise by using eye-tracking to obtain and average 50 B-scans at each identical location of interest. B-scan images were manually analyzed for GCL, retinal nerve fiber layer (RNFL), and inner plexiform layer shapes and thicknesses in the macula. MAIN OUTCOME MEASURES: Macular GCL images and thickness in normal eyes and in eyes with preperimetric glaucoma. RESULTS: The macular GCL was clearly seen on speckle noise-reduced SD-OCT images in normal eyes and eyes with preperimetric glaucoma. In each eye with preperimetric glaucoma, thinning of the macular GCL was visually apparent, particularly on vertical scans. The mean regional macular GCL was most severely thinned in the inferior perifoveal region, where its thickness was <70% of its normal thickness in 30 (81.1%) of the 37 eyes and <50% of its normal thickness in 13 (35.1%) of the 37 eyes. When the sensitivity and specificity for detecting abnormal thinning (outside the lower limit of 99% confidence interval [CI] for the means in the 39 normal eyes) in at least one 0.5-mm segment or sector were compared, the macular GCL on vertical B-scans exhibited higher sensitivity (81.1%) than the other layers on vertical B-scans (99% CI, 5.4%-59.5%; P = 0.00075-0.02100), the macular GCL (99% CI, 40.5%; P = 0.00027) on horizontal B-scans, the other layers (99% CI, 5.4%-48.6%; P<0.00048-0.00400) on horizontal B-scans, and circumpapillary RNFL automatically measured on SD-OCT (54.1%; P = 0.021), and scanning laser polarimetry with variable corneal compensation (24.3%; P = 0.00095). All the macular layers on both the vertical and horizontal B-scans and circumpapillary RNFL thickness exhibited comparable specificity (91.4-100.0%, statistically not different). CONCLUSIONS: Speckle noise-reduced SD-OCT imaging allowed clear visualization and measurement of the macular GCL, which was severely thinned in eyes with preperimetric glaucoma. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Three-dimensional high-speed optical coherence tomography imaging of lamina cribrosa in glaucoma.

OBJECTIVE: To evaluate the appearance of the optic nerve head and lamina cribrosa in patients with glaucoma using spectral/Fourier-domain optical coherence tomography (SD-OCT) and to test for a correlation between lamina cribrosa thickness measured on SD-OCT images and visual field loss. DESIGN: Observational case series. PARTICIPANTS: We evaluated 52 eyes of 30 patients with glaucoma or ocular hypertension. METHODS: The high-speed SD-OCT equipment used was a prototype system developed for 3-dimensional (3D) imaging. It had a sensitivity of 98 decibels (dB), a tissue axial resolution of 4.3 mum, and an acquisition rate of approximately 18,700 axial scans per second. For 3D analyses, a raster scan protocol of 256 x 256 axial scans covering a 2.8 x 2.8 mm disc area was used. Lamina cribrosa thickness was measured on 3D images using 3D image processing software. Correlation between lamina cribrosa thickness and mean deviation (MD) values obtained using static automatic perimetry were tested for statistical significance. MAIN OUTCOME MEASURES: Clarity of lamina cribrosa features, lamina cribrosa thickness, and MD values on static automatic perimetry. RESULTS: On 3D images, the lamina cribrosa appeared clearly as a highly reflective plate that was bowed posteriorly and contained many circular areas of low reflectivity. The dots of low reflectivity visible just beneath the anterior surface of the lamina cribrosa in en face cross-sections corresponded with dots representing lamina pores in color fundus photographs. The mean (+/-1 standard deviation) thickness of the lamina cribrosa was 190.5+/-52.7 mum (range, 80.5-329.0). Spearman rank testing and linear regression analysis showed that lamina cribrosa thickness correlated significantly with MD (Spearman sigma = 0.744; P<0.001; r(2) = 0.493; P<0.001). Different observers performed measurements of the lamina cribrosa thickness in SD-OCT cross-sectional images with high reproducibility (intraclass correlation coefficient = 0.784). CONCLUSIONS: These 3D SD-OCT imaging clearly demonstrated the 3D structure of the lamina cribrosa and allowed measurement of its thickness, which correlated significantly with visual field loss, in living patients with glaucoma. This noninvasive imaging technique should facilitate investigations of structural changes in the optic nerve head lamina cribrosa in eyes with optic nerve damage due to glaucoma. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Retinal sensitivity after intravitreal injection of bevacizumab for the treatment of macular edema secondary to retinal vein occlusion.

PURPOSE: To evaluate the change in macular function after intravitreal injection of bevacizumab for the treatment of macular edema associated with retinal vein occlusion. METHODS: For this interventional case series, 20 eyes of 20 patients with macular edema associated with retinal vein occlusion were treated with an intravitreal injection of bevacizumab. Microperimetry in the macular area was performed with a Micro Perimeter 1 before and at 1, 3, and 6 months after treatment. RESULTS: Improvement in macular function was detected immediately after treatment and lasted for at least 6 months. As measured by the Micro Perimeter 1, mean retinal sensitivities within the central 10 degrees field (4.9 +/- 2.7 dB at baseline) improved to 7.2 +/- 3.1 dB at 1 month, to 7.6 +/- 3.4 dB at 3 months, and to 7.7 +/- 3.9 dB at 6 months (P < 0.001). Of the 20 eyes, a recurrence of macular edema was observed in 14 (70%), but with the use of optical coherence tomography, integrity of the outer aspect of the foveal photoreceptors was detected at 3 months to 6 months in 15 (75%) eyes. CONCLUSION: In eyes with macular edema associated with retinal vein occlusion, improvement in macular function was detected immediately after intravitreal injection of bevacizumab and lasted for at least 6 months.

Comparison of spectral domain optical coherence tomography and color photographic imaging of the optic nerve head in management of glaucoma.

BACKGROUND AND OBJECTIVE: Spectral domain optical coherence tomography (SD-OCT) allows three-dimensional imaging of the optic disc. The objective of this study was to compare optic disc and cup margins between fundus photographs and SD-OCT. PATIENTS AND METHODS: Eighteen eyes with glaucoma were examined by a custom-built SD-OCT OCT fundus images were used to register fundus photographs and SD-OCT volume. RESULTS: Disc margins on fundus photographs corresponded to termination of the highly reflective straight line that represented the retinal pigment epithelium (RPE) or the highly reflective curved line that connected to the RPE on the OCT B-scan images at 99.3% of the positions along the disc edges. Cup margins on fundus photographs corresponded at 73.6% of the positions to the interior border of the hyporeflective regions on the OCT fundus images. CONCLUSIONS: Excellent to fair correspondence in the determination of disc and cup margins between fundus photographs and SD-OCT images was shown.

Evaluation of potential visual acuity in eyes with macular oedema secondary to retinal vein occlusion.

PURPOSE: To evaluate the potential visual acuity (VA) of eyes with macular oedema (MO) associated with retinal vein occlusion (RVO). METHODS: Thirty-one eyes of 31 patients with MO associated with RVO were examined and then treated with an intravitreal injection of bevacizumab. Of these 31 eyes, 22 showed complete resolution of the MO at 1 month after treatment, at which time potential VA was determined; 12 eyes had good function and 10 had poor function at this time. Optical coherence tomography was used to detect the junctions between inner and outer segments of the photoreceptors (IS/OS) as a hallmark of integrity of the outer photoreceptor layer. RESULTS: In the poor function group, pretreatment VA was significantly worse (P = 0.0106) and pretreatment central macular thickness was significantly greater (P = 0.0121). Preservation of the foveal photoreceptor layer before treatment was associated closely with good visual function after resolution of MO, and IS/OS line beneath the fovea was detected more frequently before treatment in eyes with good function (P = 0.0053). CONCLUSIONS: In eyes with MO associated with RVO, when the IS/OS line was detected beneath the fovea, they would be expected to have good vision after resolution of the MO.

Three-dimensional imaging of cystoid macular edema in retinal vein occlusion.

OBJECTIVE: To study the pathomorphologic features of cystoid macular edema (CME) associated with retinal vein occlusion by three-dimensional (3D) optical coherence tomography (OCT) and to study the relationship of the ocular findings to visual function. DESIGN: Observational case series. PARTICIPANTS: Twenty eyes of 20 patients with retinal vein occlusion. METHODS: A prototype 3D OCT system based on Fourier-domain OCT technology was fabricated for patient examination in this study. This system uses a superluminescent diode, which has a center wavelength of 830 nm and a bandwidth of 50 nm, as the light source, resulting in 4.3-microm axial resolution in tissue. Data acquisition rates of approximately 18 700 axial scans per second and a sensitivity of 98 dB were achieved. Three-dimensional imaging was performed by volume rendering based on the 3D data set acquired with a raster scan of 256x256 axial scans. MAIN OUTCOME MEASURES: Images of CME pathologic features obtained by 3D OCT and by Stratus OCT (Carl Zeiss, Dublin, CA). RESULTS: The 3D OCT imaging system generates a realistic 3D image of CME with high resolution. In 16 eyes, 3D OCT showed large foveal cystoid spaces, most of which were accompanied by small cystoid spaces in the parafoveal region. Cystoid spaces were seen often in the inner nuclear layer and outer plexiform layer, but were detected to some extent in all retinal layers. The 3D OCT showed clearly a thin back-reflecting line corresponding to the external limiting membrane (ELM) in 18 eyes; of these, cystoid spaces were located on the inside of the ELM in 7 eyes and appeared to be in contact with the ELM in 9 eyes. In 2 eyes, the ELM line could not be seen clearly beneath the large foveal cystoid spaces. Integrity of the ELM in the foveal region had a direct correlation with visual acuity. CONCLUSIONS: Observation of CME using 3D OCT enabled visualization of its spatial extent in each retinal layer and discernment of its relationship to the ELM. The use of 3D OCT thus may improve the monitoring of CME progression and its response to treatment.

Foveal photoreceptor layer in eyes with persistent cystoid macular edema associated with branch retinal vein occlusion.

PURPOSE: To study the correlation of visual acuity and the foveal photoreceptor layer in eyes with persistent cystoid macular edema associated with branch retinal vein occlusion (BRVO). DESIGN: Retrospective chart review. METHODS: We studied retrospectively the medical records of 42 eyes of 42 patients with persistent cystoid macular edema secondary to BRVO, eyes in which the foveal thickness was greater than 250 microm at final examination. On the vertical image obtained by optical coherence tomography at the final examination, we measured thickness of the foveal photoreceptor layer that was beneath the foveal cystoid spaces. We also assessed status of the junction between inner and outer segments of the photoreceptors (IS/OS) in the fovea. RESULTS: The photoreceptor layer beneath the foveal cystoid spaces was detected as a distinct layer with thickness varying between 33 microm and 124 microm (mean, 71.1 +/- 26.8 microm). Final visual acuity showed no correlation with total foveal thickness (r = 0.336, P = .092). However, it did show a close correlation with thickness of the foveal photoreceptor layer (r = -0.571, P < .0001). Of the 42 eyes, 15 showed a continuous IS/OS line in the fovea. Visual acuity in these eyes with a continuous IS/OS line in the fovea was significantly better than that in eyes with a discontinuous or interrupted IS/OS line (P < .0001). CONCLUSIONS: Both the thickness and the integrity of the foveal photoreceptor layer are associated with visual function in eyes with persistent cystoid macular edema associated with BRVO.

Integrity of foveal photoreceptor layer in central retinal vein occlusion.

PURPOSE: To study the correlation between final visual acuity and integrity of the foveal photoreceptor layer after resolution of macular edema (ME) associated with central retinal vein occlusion (CRVO). METHODS: We studied retrospectively 27 eyes of 27 patients with resolved ME associated with central retinal vein occlusion. On optical coherence tomography, integrity of the foveal photoreceptor layer was studied using the junctions between inner and outer segments of the photoreceptor (IS/OS) line as a hallmark. RESULTS: At the final visit, foveal thickness was decreased to a physiologic level in all eyes. On optical coherence tomography, 14 eyes showed the IS/OS line in the fovea, whereas 13 eyes showed no IS/OS line. In concordance with resolution of the ME, visual acuity had improved significantly by the final visit. However, final visual acuity in eyes without an IS/OS line was significantly poorer than that in eyes with an IS/OS line (P < 0.0001). In addition, integrity of the foveal photoreceptor layer after resolution of the ME had a significant correlation with the initial retinal perfusion status (P = 0.0156) and with initial visual acuity (P = 0.0050). CONCLUSIONS: After resolution of the ME associated with central retinal vein occlusion, visual acuity is closely associated with integrity of the foveal photoreceptor layer.

Three-dimensional imaging of macular inner structures in glaucoma by using spectral-domain optical coherence tomography.

PURPOSE: To profile macular thickness changes in glaucoma by using three-dimensional spectral-domain optical coherence tomography (3D-SD-OCT). METHODS: The study included 30 eyes with suspected glaucoma and preperimetric glaucoma (SGPPG) and 35 healthy eyes. The macular thickness, including those of the total retina, nerve fiber layer (NFL), and combined inner retinal layers (IRLs)-NFL+ganglion cell layer (GCL)+inner plexiform layer (IPL)-was measured by 3D-SD-OCT raster scans in a 6 mm(2) region. The average and sectoral thicknesses were calculated on an Early Treatment of Diabetic Retinopathy Study (ETDRS) chart and a ETDRS chart with a 45° rotation (glaucoma sector chart, GSC). RESULTS: The mean IRL thickness was significantly less in the SGPPG eyes than in the healthy eyes, but the mean total retinal and macular NFL thicknesses were not. In the SGPPG eyes, the IRLs were thinner in the outer macula than in the inner macula, in the inferior hemisphere than in the superior hemisphere, and in the temporal hemisphere than in the nasal hemisphere. The significantly thinned sectors were nearly identical on the GSC but only slightly overlapped on the ETDRS chart. The IRLs in the inferior temporal outer sector (GSC) had the greatest area under the receiver operating characteristic curve, which was significantly greater than those for the IRLs over the entire macula, inferior hemiretinal region, and inferior outer hemicircular region (macular subfields), and that for the circumpapillary NFL in the inferior sectors (P = 0.001-0.036). CONCLUSIONS: Macular IRL thickness measured by using 3D-SD-OCT is useful for profiling macular atrophy in SGPPG.

Serous retinal detachment associated with retinal vein occlusion.

PURPOSE: To study the pathomorphology of serous retinal detachment (RD) associated with retinal vein occlusion by optical coherence tomography (OCT). DESIGN: Retrospective chart review. METHODS: Ninety-one eyes of 91 patients with macular edema associated with retinal vein occlusion had undergone a comprehensive ophthalmologic examination, including measurement by spectral-domain OCT. RESULTS: Eyes with macular edema associated with retinal vein occlusion typically showed foveal cystoid spaces and marked retinal swelling, especially in the outer retina. In addition, 76 eyes (83.5%) showed serous RD involving the fovea, which ranged in thickness from 64 microm to 871 microm (219.2 +/- 161.6 microm). Fifty-two eyes showed a small pointed RD, with a small base. The point of the RD was always located beneath the fovea, where the outer surface of the swollen neurosensory retina seemed to be contracted inward, resulting in development of the pointed RD. Two eyes with no RD at the initial visit developed such a pointed RD during follow-up. In contrast, 24 eyes showed a more dome-shaped RD, with a large base, and in 18 eyes, a pointed RD seen at the initial visit changed into a dome-shaped RD during follow-up. In some cases, small outer retinal discontinuity was seen on the external surface of the swollen neurosensory retina. CONCLUSIONS: In eyes with retinal vein occlusion, a small pointed RD initially developed just beneath the fovea, but subsequently changed into a dome-shaped RD. Based on the findings by OCT, we hypothesize that the foveal architecture, especially that of the Müller cell cone, is involved in the formation of serous RD.

Three-dimensional imaging of the macular retinal nerve fiber layer in glaucoma with spectral-domain optical coherence tomography.

PURPOSE: To investigate the three-dimensional (3D), spectral-domain (SD) optical coherence tomography (3D,SD-OCT) imaging of the macular retinal nerve fiber layer (RNFL) in eyes with glaucoma. METHODS: The study included 38 eyes of 38 patients with glaucoma and 38 normal eyes of 38 volunteers. With a 3D raster scan SD-OCT protocol, 512 × 128 axial scans were acquired over a 6-mm(2) area of the macula. Findings on 3D,SD-OCT images were compared with those on color and red-free fundus photographs and time-domain (TD) OCT. RESULTS: Fourteen (30.4%) more RNFL defects were detected on 3D,SD-OCT images than on color fundus photographs. Of these 14, 12 were detected in 10 (90.9%) of 11 eyes with tessellated fundi (P < 0.0001). On 3D,SD-OCT images, complete loss of the RNFL reflectivity was seen in 63.0% of the RNFL defects and thinning of the RNFL in the rest. On TD-OCT cpRNFL analysis, RNFL defects that appeared on 3D,SD-OCT as a complete loss of RNFL reflectivity were detected more often (P = 0.012) than those that appeared as thinning of the RNFL. Inter-rater agreement was better for RNFL defects on 3D,SD-OCT (0.85) than for those on color (0.62-0.64) or red-free (0.68-0.70) fundus photographs. However, 3D,SD-OCT macular RNFL thickness measurements were substantially reproducible but not as reproducible as macular retinal thickness measurements, and neither was as sensitive as TD-OCT cpRNFL thickness measurements for detecting glaucoma. CONCLUSIONS: 3D,SD-OCT imaging of the macular RNFL is an effective means of detecting macular RNFL defects and their severity in eyes with glaucoma.