Anjum F. Koreishi

Photoreceptor Layer Thinning over Drusen in Eyes with Age-Related Macular Degeneration Imaged In Vivo with Spectral-Domain Optical Coherence Tomography

PURPOSE Detect changes in the neurosensory retina using spectral-domain optical coherence tomography (SD OCT) imaging over drusen in age-related macular degeneration (AMD). Quantitative imaging biomarkers may aid in defining risk of disease progression. DESIGN Cross-sectional, case-control study evaluating SD OCT testing in AMD. PARTICIPANTS AND CONTROLS Seventeen eyes of 12 subjects with nonneovascular AMD and drusen and 17 eyes of 10 age-matched control subjects. METHODS Spectral-domain OCT imaging across the fovea in the study eye with multiple 10- to 12-mm scans of 1000 A scans each. MAIN OUTCOME MEASURES In summed SD OCT scans, the height of individual retinal layers either over drusen or at corresponding locations in the control eye and qualitative changes in retinal layers over drusen. Secondary measures included photoreceptor layer (PRL) area, inner retinal area, and retinal pigment epithelium (RPE)/drusen area. RESULTS The PRL was thinned over 97% of drusen, average PRL thickness was reduced by 27.5% over drusen compared with over a similar location in controls, and the finding of a difference was valid and significant (P=0.004). Photoreceptor outer segments were absent over at least 1 druse in 47% of eyes. Despite thinning of the PRL, inner retinal thickness remained unchanged. We observed 2 types of hyperreflective abnormalities in the neurosensory retina over drusen. Distinct hyperreflective speckled patterns occurred over drusen in 41% of AMD eyes and never in control eyes. A prominent hyperreflective haze was present in the photoreceptor nuclear layer over drusen in 67% of AMD eyes and more subtly in the photoreceptor nuclear layer in 18% of control eyes (no drusen). CONCLUSIONS With SD OCT as used in this study, we can easily detect and measure changes in PRL over drusen. Decreased PRL thickness over drusen suggests a degenerative process, with cell loss leading to decreased visual function. The hyperreflective foci overlying drusen are likely to represent progression of disease RPE cell migration into the retina and possible photoreceptor degeneration or glial scar formation. A longitudinal study using SD OCT to examine and measure the neurosensory retina over drusen will resolve the timeline of degenerative changes relative to druse formation.

Drusen Ultrastructure Imaging with Spectral Domain Optical Coherence Tomography in Age-related Macular Degeneration

PURPOSE To categorize drusen ultrastructure in age-related macular degeneration (AMD) using spectral domain optical coherence tomography (SDOCT) and correlate the tomographic and photographic drusen appearances. DESIGN Prospective case series. PARTICIPANTS Thirty-one eyes of 31 patients with non-neovascular AMD. METHODS Subjects with drusen and a clinical diagnosis of AMD were enrolled in an SDOCT imaging study from August of 2005 to May of 2007. Foveal linear scans were acquired, and the image data were processed for analysis. Drusen were scored by 4 morphologic categories: shape, predominant internal reflectivity, homogeneity, and presence of overlying hyper-reflective foci. The prevalences of each morphologic pattern and combinations of morphologic patterns observed were calculated. The photographic appearance of each druse was compared with the tomographic classification. Interobserver and intraobserver agreement analysis was performed. MAIN OUTCOME MEASURES Prevalence of morphologic parameters using SDOCT. RESULTS Twenty-one eyes of 21 patients had SDOCT B-scans of adequate quality for analysis. On the basis of the above morphologic categories, 17 different drusen patterns were found in 120 total drusen. The most common was convex, homogeneous, with medium internal reflectivity, and without overlying hyper-reflective foci, present in 17 of 21 eyes (81%). Of the 16 eyes (76%) with nonhomogeneous drusen, 5 had a distinct hyper-reflective core. Hyper-reflective foci overlying drusen were in 7 eyes (33%). Although half of the photographically soft-indistinct drusen were convex with medium internal reflectivity and homogeneous without overlying hyper-reflective foci, the other half had significant variability in their tomographic appearance. Both interobserver and intraobserver agreement in drusen grading were high. Readers agreed the most when grading drusen shape and reflectivity, whereas the least agreement was for drusen homogeneity. CONCLUSIONS Drusen ultrastructure can be imaged with SDOCT and characterized with a simple grading system. Photographic appearance may predict some but not all tomographic appearances. Trained observers have a high level of agreement with this grading system. These in vivo morphologic characteristics imaged with SDOCT may be distinct subclasses of drusen types, may relate closely to ultrastructural drusen elements identified in cadaveric eyes, and may be useful imaging biomarkers for disease severity or risk of progression. This will require validation from further studies.

Spectral Domain Optical Coherence Tomography Imaging of Geographic Atrophy Margins

OBJECTIVE To test in vivo whether spectral domain optical coherence tomography (SD-OCT) provides adequate resolution for reproducible measurement of photoreceptor (PR) layer at the margins of geographic atrophy (GA), and if it delineates the relationship between PR layer and retinal pigment epithelium at the margins of GA. DESIGN Prospective consecutive case series. PARTICIPANTS Patients with GA secondary to nonneovascular age-related macular degeneration (AMD) identified during routine follow-up at Duke Eye Center between January 3, 2006, and June 3, 2007, and who consented to participate in this study. METHODS We used SD-OCT to image eyes. Multiple B-scans from each eye were saved and independently graded by 2 graders and the following locations were marked: (1) site where PR thickness began to decline below its baseline, (2) site where PR layer disappeared, and (3) site of the GA margin. These data were processed to calculate the locations of PR losses relative to GA margins and were categorized as (A) bridging across GA margins, (B) entirely within GA margins, or (C) entirely outside GA margins. MAIN OUTCOME MEASURES Location of PR loss (bridging across GA margins, entirely within GA margins, or entirely outside GA margins) was calculated. Distances from the GA margin were measured for beginning and ending of PR loss. Interobserver agreement was determined for categories of PR loss as well as locations of PR loss relative to the GA margin. RESULTS We analyzed 500 unique scans. The PR loss occurred most frequently bridging across the GA margin (65% scans), second most frequently entirely inside the GA margin (29% scans), and least frequently entirely outside the GA margin (6% scans). Loss of PR started an average of 61 microm (standard deviation [SD] +/- 235) outside the GA margin, ended an average of 311+/-273 microm inside the GA margin, and spanned an average of 372+/-179 microm. CONCLUSIONS Relative to GA margins in non-neovascular AMD with GA, SD-OCT provides adequate resolution for quantifying PR loss. It may also serve as a means of tracking disease progression in future interventional trials. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

Abnormal Foveal Morphology in Ocular Albinism Imaged With Spectral-Domain Optical Coherence Tomography

OBJECTIVES To evaluate the spectrum of foveal architecture in pediatric albinism and to assess the utility of spectral-domain optical coherence tomography (OCT) in ocular imaging of children with nystagmus. METHODS Spectral-domain OCT imaging was performed on study subjects in 3 groups: subjects with ocular albinism (OA) or suspected OA with foveal hypoplasia, with nystagmus, and with or without iris transillumination; a subject with oculocutaneous albinism and Hermansky-Pudlak syndrome; and control subjects. Dense volumetric scans of each fovea were captured using standard and handheld spectral-domain OCT devices. Images were postprocessed and scored for the presence and configuration of each retinal layer across the fovea. RESULTS High-quality spectral-domain OCT images obtained from each subject revealed a range of abnormalities in subjects with OA or suspected OA and the subject with oculocutaneous albinism and Hermansky-Pudlak syndrome: persistence of an abnormal, highly reflective band across the fovea, multiple inner retinal layers normally absent at the center of the fovea, and loss of the normally thickened photoreceptor nuclear layer at the fovea when compared with that in control subjects. The optic nerve was elevated in multiple eyes of subjects with OA or suspected OA and the subject with oculocutaneous albinism and Hermansky-Pudlak syndrome. CONCLUSIONS A spectrum of foveal morphological abnormalities is seen in subjects with OA or suspected OA, which in some cases contrasted with previous studies using time-domain OCT. These OCT findings clarify the morphology of foveal hypoplasia seen clinically. This imaging modality may be useful in evaluating children.

Developing SDOCT to assess donor human eyes prior to tissue sectioning for research

BackgroundTo compare spectral domain optical coherence tomography (SDOCT) cross-sectional images of human central retina obtained from donor eyes with and without age-related macular degeneration (AMD) to corresponding histopathology from light micrographs. To establish the utility of SDOCT for localizing pathology in the posterior eyecup, for identifying ocular disease in donor eyes, or for directing subsequent sectioning of retinal lesions for research.MethodsSeven consecutive human donor eyes were selected based on age. The eyes, with the anterior segment removed, were imaged by SDOCT with a focusing aspheric lens. Four eyes were from donors with a clinical history of AMD, and three were from age-matched donors with no history of AMD. Histopathological correlation of morphological changes detected in three eyes by SDOCT was obtained for comparison to step serial-sectioned light microscopy images of the formalin-fixed, paraffin-embedded retina. A simplified imaging setup was tested on an enucleated porcine eye for comparison.ResultsAMD pathology was detected and localized in four eyes by SDOCT. The SDOCT images correlated with the histopathology observed by light microscopy in each sectioned eye. Pathologies included a subfoveal neovascular lesion with subretinal fluid, peripapillary neovascularization, epiretinal membrane, foveal cyst, choroidal folds, and drusen. Similar imaging was possible with the simplified setup.ConclusionsSDOCT imaging identified retinal disease of the posterior eyecup in human donor eyes. Pathology detected with SDOCT was verified by light microscopy in three eyes, supporting the utility of SDOCT as a screening tool for research.

Chronic postoperative endophthalmitis after cataract surgery secondary to vancomycin-resistant Ochrobactrum anthropi: case report and literature review

BackgroundThe aim of this study was to report an unusual case of chronic postoperative endophthalmitis following cataract surgery, secondary to Ochrobactrum anthropi that was found to be resistant to vancomycin.FindingsAnterior chamber paracentesis cultures grew gram negative bacilli Ochrobactrum anthropi. The patient was treated with a series of intracameral injections of moxifloxacin, with adjuvant oral moxifloxacin. Posterior sub-Tenon and oral corticosteroids were used to treat cystoid macular edema. Explantation of the intraocular lens (IOL)-capsular bag complex was avoided.ConclusionsChronic postoperative endophthalmitis is a rare entity, often due to indolent pathogens that sequester in the capsular bag. Aggressive surgical intervention may be avoided with the use of adequate intraocular antibiotic, provided that the offending organism demonstrates appropriate antibiotic susceptibilities.

Poststreptococcal syndrome presenting as posterior scleritis in a child

Posterior scleritis in children is very rare. In contrast to the adult form, pediatric posterior scleritis has not previously been associated with any systemic disorder. We describe a case of an 11-year-old girl who presented with left eye pain and redness and was found to have posterior scleritis on ultrasonography. Her laboratory work-up revealed a highly elevated antistreptolysin O titer; the rest of her serologic and radiologic evaluation was unremarkable. She was diagnosed with presumed poststreptococcal posterior scleritis and improved with a slow taper of oral steroids.

Visualization of Photoreceptors in Birdshot Chorioretinopathy Using Adaptive Optics Scanning Laser Ophthalmoscopy: A Pilot Study

Abstract Purpose: Adaptive optics scanning laser ophthalmoscopy (AOSLO) allows en face visualization of specific layers of the retina. This pilot study evaluated the ability of AOSLO to visualize photoreceptor integrity in patients with birdshot chorioretinopathy (BCR). Method: A total of 16 consecutive patients with HLA-A29+ BCR were imaged using the prototype Apaeros retinal imaging system. Images of high quality were aligned with infrared reflectance photos and correlated with spectral domain optical coherence tomography (SD-OCT). Results: Images of four eyes of three patients were of sufficient quality to allow posterior pole montage and point-to-point correlation with SD-OCT. Areas of photoreceptor disruption on SD-OCT were seen as patchy areas of loss on AOSLO, whereas areas of intact interdigitation zone and inner segment/outer segment junction correlated with normal appearing photoreceptors on AOSLO. Conclusions: Using AOSLO, we found one instance of subclinical photoreceptor disruption not seen on SD-OCT. Ultimately, there are unique challenges associated with imaging BCR patients using AOSLO.