Search

Purpose To investigate the regeneration of the cone outer segments in eyes after surgery for fovea-off rhegmatogenous retinal detachment with an adaptive optics (AO) fundus camera and to correlate these findings with the findings of optical coherence tomography (OCT). Design Retrospective, observational case series. Methods Medical charts of 21 eyes of 21 patients who had undergone surgery for fovea-off rhegmatogenous retinal detachment were retrospectively studied. Cone mosaic images were obtained with an AO fundus camera. Cone packing density at 2 degrees from the fovea within the previously detached area was measured 6 and 12 months after surgery. Retinal thicknesses between the interdigitation zone and the retinal pigment epithelium (IZ-RPE) and between the ellipsoid zone and the retinal pigment epithelium (EZ-RPE) were measured in OCT images. Results Cone density 12 months after surgery was significantly increased from that at 6 months ( P = .001), but was still significantly lower than that of normal fellow eyes ( P P = .045, P = .033, respectively), and these values were not significantly different from those of normal fellow eyes. Multivariate analysis showed that cone density at 12 months was significantly associated with IZ-RPE thickness ( P = .002), and increases in cone packing density were significantly associated with increases in IZ-RPE thickness ( P = .001). Conclusions Recovery of cone packing density measured by AO was associated with structural recovery of the outer retina observed in OCT, suggesting regeneration of the photoreceptor outer segment after surgery.

Purpose To investigate whether the photoreceptor layer status of the detached retina, which has the potential to plug the macular hole (MH), can predict postoperative visual acuity (VA). Design Retrospective, consecutive, observational case series. Methods A consecutive series of 48 eyes in 48 patients with surgically closed MHs were recruited into the study. Spectral-domain optical coherence tomography (SD OCT) images were obtained preoperatively and postoperatively. Length gaps between photoreceptor layers and the preoperative diameter of the basal MH in the detached part of the retina was calculated for the photoreceptor outer segment (OS) and the external limiting membrane (ELM). The postoperative photoreceptor layer status at the fovea, including continuity of the ELM line, inner segment ellipsoid line (ISe), and cone outer segment tip (COST) line, was categorized by graders. Results The preoperative OS gap length and ELM gap length correlated significantly with postoperative VA. A larger OS or ELM gap length was associated with a more severe postoperative photoreceptor layer status. Eyes with a moderately reflective lesion had a significantly longer OS gap length and ELM gap length, significantly worse postoperative VA, and more severe photoreceptor layer status than did eyes without such a moderately reflective lesion. Eyes with a better postoperative COST status had significantly better postoperative VA ( P = .0465). Conclusions OS and ELM gap length, which represent the degree of insufficiency of MH plugging, was strongly correlated with postoperative VA; moreover, these preoperative parameters were associated with the postoperative photoreceptor layer status, including glial cell proliferation.

To report photoreceptor restoration and visual outcomes after vitrectomy for retinal detachment.Retrospective, observational case series.We prospectively studied the tomographic features of reattached retinas in 20 eyes with a macula-off rhegmatogenous retinal detachment using spectral-domain optical coherence tomography 1, 3, and 6 months after 3-port vitrectomy with SF(6) gas tamponade. All eyes were examined more than 3 months after surgery.The optical coherence tomography foveal findings were classified as a disrupted inner segment and outer segment (IS/OS) line, a residual foveal detachment, and a continuous IS/OS line. A disrupted IS/OS line was seen in 11 eyes (55%) at 1 month and in 8 eyes (40%) at 3 months, a foveal detachment was seen in 8 eyes (40%) at 1 month and in 7 eyes (35%) at 3 months, and a continuous IS/OS line was seen in 1 eye (5%) at 1 month and in 5 eyes (25%) at 3 months. In 18 eyes followed up for 6 months, optical coherence tomography showed a disrupted IS/OS line in 3 eyes (17%), a foveal detachment in 6 eyes (33%), and a continuous IS/OS line in 9 eyes (50%). The mean best-corrected visual acuities at 1 and 6 months were 0.26 and 0.16 with a disrupted IS/OS line, 0.60 and 0.95 with a foveal detachment, and 0.8 and 0.95 with a continuous IS/OS line. The mean best-corrected visual acuity was significantly (P.0001) lower with a disrupted IS/OS line compared with the other formations at 6 months.The IS/OS line at the fovea recovered gradually after surgery. The postoperative visual acuity was correlated with a restored IS/OS line.

Purpose To investigate the correlation between visual field (VF) defects in diseases of the acute zonal occult outer retinopathy (AZOOR)-complex and their spectral-domain optical coherence tomographic (OCT) findings. Design Observational case series. Methods Patients with AZOOR, multiple evanescent white dot syndrome (MEWDS), and multifocal choroiditis and panuveitis (MCP) examined in a private practice retinal referral center had threshold VF testing and spectral-domain OCT examination performed using a device capable of obtaining a block of 128 B-scans in a 6 × 6-mm region centered on the optic nerve and macula. The areas of defects in the boundary between the inner segments (IS) and the outer segments (OS) of the photoreceptors, termed the IS/OS boundary, were compared with the VF defects measured. Results There were 18 evaluable eyes among one patient with MEWDS, two with AZOOR, and seven with MCP. In the 14 eyes with blind spot enlargement, corresponding IS/OS boundary defects were found in the four eyes peripapillary region, while no IS/OS boundary defects were found in the five eyes without blind spot enlargement. IS/OS boundary defects were seen over chorioretinal scars and areas of neovascularization and no widespread defects were seen elsewhere in the fundus. The IS/OS boundary defects showed improvement, as did the blind spot enlargement, spontaneously in the patient with MEWDS and after treatment with immunosuppression in the patients with AZOOR. Conclusion The spectral-domain OCT finding of IS/OS boundary defects, implicating photoreceptor OS perturbation, appears to explain the blind spot enlargement in patients with AZOOR-complex diseases. These defects are not necessarily permanent.

Purpose To investigate photoreceptor segment morphologic changes at the detached retina in central serous chorioretinopathy (CSC). Design Observational case series. Methods We measured and compared the distance between the internal limiting membrane (ILM) and the external limiting membrane (ELM), between the ELM and the photoreceptor inner and outer segment junction (IS/OS) at the central fovea, and the length of the longest outer segment in 20 consecutive CSC eyes and 10 normal eyes on Fourier domain optical coherence tomography (FD-OCT) images. We evaluated the correlation between the length of the outer segment and age, best-corrected visual acuity (BCVA), and symptom duration in CSC eyes and the correlation between retinal thickness from the ILM to ELM and the other parameters. Results The median distance between the ILM and ELM was 75 μm in the CSC eyes and was significantly ( P = .0001) shorter than the median 135 μm in normal eyes. The median distance between the ELM and IS/OS was 35 μm in normal eyes and CSC eyes. The median longest outer segment length in CSC eyes was 90 μm and was significantly ( P = .01) longer than the 60 μm in normal eyes. The outer segment length was not or weakly correlated with age ( r s = 0.38), BCVA ( r s = 0.09), or symptom duration ( r s = 0.19). The distance between the ILM and ELM was weakly correlated with age ( r s = 0.34), BCVA ( r s = 0.34), or symptom duration ( r s = 0.28). Conclusions FD-OCT showed elongation of photoreceptor outer segments and decreased thickness of the outer nuclear layer in CSC.

Purpose To report an image analysis algorithm that was developed to provide quantitative thickness measurement of retinal layers on optical coherence tomography (OCT) images. Design Prospective cross-sectional study. Methods Imaging was performed with an OCT3 commercial instrument in 10 visually normal healthy subjects. A dedicated software algorithm was developed to process the raw OCT images and detect the depth location of peaks from intensity profiles. Quantitative thickness measurements of three retinal layers, in addition to total retinal thickness, were derived. Total retinal thickness measurements obtained by the algorithm were compared with measurements provided by the standard OCT3 software. Results The total retinal thickness profile demonstrated foveal depression, corresponding to normal anatomy, with a thickness range of 160 to 291 μm. Retinal thickness measured by the algorithm and by the standard OCT3 software were highly correlated ( R = 0.98). The inner retinal thickness profile predictably demonstrated a minimum thickness at the fovea, ranging between 58 to 217 μm along the 6-mm scan. The outer retinal thickness profile displayed a maximum thickness at the fovea, ranging between 66 to 107 μm along the 6-mm scan. The photoreceptor outer segment thickness profile was relatively constant along the 6-mm scan through the fovea, ranging between 42 to 50 μm. The intrasubject variabilities of the inner retina, outer retina, and photoreceptor outer segment thickness was 14, 10, and 6 μm, respectively. Conclusions Thickness measurements of retinal layers derived from OCT images have potential value for objectively documenting disease-related retinal thickness abnormalities and monitoring progressive changes over time.

Purpose To investigate the characteristics of subretinal exudation and consequent morphologic changes in acute central serous chorioretinopathy (CSC) using spectral-domain optical coherence tomography (OCT). Design Prospective, observational, cross-sectional case series. Methods Patients with CSC with symptom duration of fewer than 3 months underwent visual acuity measurement, fundus observation and spectral-domain OCT examinations and then were evaluated for subretinal exudation and other changes. Results A total of 123 patients (123 eyes) were included, all showing various retinal pigment epithelium (RPE) abnormalities on OCT. OCT also showed subretinal exudation (65 eyes, 52.8%); retinal dipping (14 eyes, 11.4%); and photoreceptor layer defects (88 eyes, 71.5%). Without exception, the locations of these pathologic changes were closely related to the abnormal sites in the RPE. Those with subretinal exudation showed shorter durations of symptoms, whereas those with photoreceptor layer defects showed longer durations. In most eyes with retinal dipping, exudation connected it to RPE abnormalities. The defects of the photoreceptor layer, which involved the photoreceptor outer segment in 68 eyes, the photoreceptor inner segment in 20 eyes, and the outer nuclear layer as well, were likely to be the consequence of retinal dipping. Conclusions OCT findings suggested that in eyes with acute CSC subretinal exudation, which indicated fibrin leakage through the RPE defects, might cause retinal dipping, thus leading to photoreceptor layer defects, and that spectral-domain OCT could provide a better understanding of the pathologic changes in acute CSC.

Purpose To determine the origin of fundus autofluorescence (AF) patterns in central serous chorioretinopathy (CSC). Design Retrospective, observational case series. Methods We retrospectively studied 30 consecutive eyes of 30 patients with primary CSC using AF and spectral-domain optical coherence tomography (SD-OCT). We measured the AF using the Heidelberg Retina Angiograph with a 488-nm excitation light and a 500-nm cutoff barrier filter and compared the AF patterns with ophthalmoscopy and SD-OCT. Results We observed a patchy increased AF in the macular area in 22 eyes (73%), in which the length of the photoreceptor outer segment at the central fovea tended to be longer than the other eyes ( P = .06). The punctate increased AF corresponded to the ophthalmoscopic precipitates in 17 eyes with precipitates. AF significantly ( P = .017) decreased in eyes with a prominent serous retinal detachment (SRD). Eight eyes (27%) had increased AF in the inferior SRD. Conclusions The patchy increased AF appears to originate from elongated photoreceptor outer segments in the detached retina. The autofluorescent fluorophores from the photoreceptor outer segments may be concentrated in precipitates or have settled into the inferior SRD.

Purpose To evaluate restoration of the photoreceptor outer segment and visual outcomes in closed macular holes. Design Retrospective case series. Methods We retrospectively observed the reparative process of macular holes in 28 eyes one, three, and six months postoperatively using spectral-domain optical coherence tomography. We evaluated the reflective line at the junction between the photoreceptor inner and outer segment (IS/OS) and the best-corrected visual acuity (BCVA). Results The outer photoreceptor layer showed a foveal detachment, a disrupted IS/OS line, or both one month postoperatively. No eye had a continuous IS/OS line. These abnormalities were gradually restored at various levels. At six months, nine eyes had a normal outer photoreceptor layer, four eyes outer foveal defects with a continuous IS/OS line, 12 eyes a disrupted IS/OS line, and three eyes outer foveal defects with a disrupted IS/OS line. The mean BCVAs were significantly ( P = .017) lower in groups with a disrupted IS/OS line compared to groups with a continuous IS/OS line with or without outer foveal defects. Conclusions Macular hole closure is attained by bridge formation (foveal detachment) and the IS/OS line heals in varying degrees. The visual outcomes were significantly better in eyes with a continuous IS/OS line than in those with a disrupted IS/OS line.

tomography for evaluation of macular pathologic features in uveitis. Am J Ophthalmol 2008;145:1018–1022. 2. Leung CK, Cheung CY, Weinreb RN, et al. Comparison of macular thickness measurements between time-domain and spectral-domain optical coherence tomography. Invest Ophthalmol Vis Sci. Forthcoming. 3. Forooghian F, Cukras C, Meyerle CB, Chew EY, Wong WT. Evaluation of time-domain and spectral-domain optical coherence tomography in the measurement of diabetic macular edema. Invest Ophthalmol Vis Sci. Forthcoming. 4. Costa RA, Calucci D, Skaf M, et al. Optical coherence tomography 3: Automatic delineation of the outer neural retinal boundary and its influence on retinal thickness measurements. Invest Ophthalmol Vis Sci 2004;45:2399–2406. 5. Matsumoto H, Kishi S, Otani T, Sato T. Elongation of photoreceptor outer segment in central serous chorioretinopathy. Am J Ophthalmol 2008;145:162–168.

Retinitis pigmentosa (RP) refers to a heterogeneous group of genetic retinal disorders that primarily affect the rod and cone photoreceptors and the retinal pigment epithelium (RPE). Its prevalence in the United States is roughly 1/4000.1–4 RP is a slowly progressive disease, and typically affects the rods before the cones, although this is not always the case. RP can be an isolated finding, or it can be associated with other systemic conditions. Several genes have been found to be associated with RP, and it can be inherited as an X-linked, autosomal dominant, or autosomal recessive condition. Cases of RP with no known family history, referred to as RP simplex, can also occur. Diagnosis of RP is usually based on characteristic findings in clinical history and examination. Typical findings include disease onset in young adulthood, nyctalopia, peripheral vision loss, RPE disruption in the form of atrophy and “bone spicules,” disk pallor, retinal vessel attenuation, and characteristic electroretinogram (ERG) appearance showing diffuse photoreceptor disease. RP can predispose patients to cystoid macular edema (CME), epiretinal membranes (ERM), posterior subcapsular cataracts, and pigmented flecks and syneresis of the anterior vitreous.1–4 RP encompasses a heterogeneous group of disorders; therefore, clinical findings vary widely from patient to patient. An abundance of histopathologic studies examining a variety of different subtypes of RP at various stages of the disease are in publication.4 The earliest histopathologic change in all forms of RP is shortening of both the rod and cone photoreceptor outer segments. As the disease progresses, loss of rod photoreceptors usually occurs first in the mid-periphery and then extends toward the macula. Cone photoreceptor loss occurs later.4–7 After photoreceptor death, RPE cells migrate inward toward the retinal blood vessels, creating the characteristic spiculated appearance on fundus examination.8,9 Secondary changes of inner retinal neurons and retinal glia also have also been documented.4 Optical coherence tomography (OCT) is a new and well-recognized method of determining in vivo retinal architecture. OCT has been used in diagnosing and following a number of different diseases, and has proven particularly useful and accurate in measuring retinal thickness.10–16 Several OCT studies of RP are reported, most of which show the capability of OCT to recognize and follow CME in RP patients. 17–20 However, visualizing and quantifying microstructural changes within the photoreceptor and RPE layers is difficult using standard resolution OCT, capable of ~ 10 μm axial resolution. As these are the layers involved in RP, imaging them may be useful in diagnosing and classifying different subtypes of the disease. A new generation of ultra-high resolution optical coherence tomography (UHR-OCT) technology that significantly improves axial image resolution has recently been developed.21 Using a state of the art femtosecond laser as the light source for OCT imaging, this new technology achieves an axial image resolution of ~3 μm in the human eye. The enhanced imaging capability of UHR-OCT improves visualization of intraretinal layers such as the ganglion cell layer, photoreceptor layers, and retinal pigment epithelium.21–23 UHR-OCT has been used clinically to quantify transverse photoreceptor damage in Stargardt disease.24 The current study demonstrates UHR-OCT images from a series of patients with the diagnosis of RP or related diseases. The images were compared with those taken from a series of normal eyes. Central foveal thickness (CFT) and foveal photoreceptor outer segment/pigment epithelium thickness (FOSPET) were defined, measured, and compared between the two groups. CFT and FOSPET in RP patients were also correlated with visual acuity. Both measurements include the thickness of the photoreceptor outer segments.

We studied an eye from a 73-year-old man with a sporadic type of retinal cone degeneration and choroidal melanoma. Histologic and ultrastructural studies of the nasal retina unaffected by the choroidal melanoma showed alterations at the outer retina predominantly involving the photoreceptors and retinal pigment epithelium. A wide spectrum of pathologic changes were observed, ranging from near normal retina showing only photoreceptor outer segment disease (distortion and kinking) to grossly pathologic regions where photoreceptor cell bodies were sparse and their outer segments absent. The retinal pigment epithelium in minimally affected regions of the retina showed an increased proportion of the melanin complement of the cell within complex granules. In severe disease, many cells showed only giant complex granules with no free melanin. Retinal pigment epithelial cell migration and relocation around blood vessels was also noted in severe disease.

We studied both eyes of a 66-year-old man with retinal degeneration and oat cell carcinoma of the bronchus. Retinal degeneration was most marked peripheral to the parafovea where photoreceptor cells and their outer segments were absent. Within the parafovea, photoreceptor cells remained but rod outer segments were absent and cone outer segments were fragmented and disorganized. The retinal pigment epithelium contained many immature melanin granules within melanolysosomes, suggesting abnormal melanin synthesis and resorption. We suggest that a pharmacologically active substance resembling a hormone produced by the tumor increased melanin synthesis in the pigment epithelium and that the increased melanin content in these cells compromised their ability to phagocytose and maintain normal turnover of photoreceptor outer segments. We believe these changes led to photoreceptor outer segment loss and subsequent degeneration of the photoreceptor cells.