CENTRAL RETINAL ARTERY OCCLUSION WITH CILIORETINAL ARTERY SPARING AFTER LASER-ASSISTED IN SITU KERATOMILEUSIS.

PURPOSE: To report a central retinal artery occlusion with cilioretinal artery sparing in a 48-year-old woman after laser-assisted in situ keratomileusis surgery. METHODS: Case history and clinical examination including best-corrected visual acuity, serum markers, slit-lamp biomicroscopy, indirect ophthalmoscopy, fundus photography, fluorescein angiography, and optical coherence tomography. RESULTS: A 48-year-old woman underwent routine laser-assisted in situ keratomileusis surgery in both eyes. On postoperative Day 1, vision was 20/20 in both eyes with full visual fields by confrontation. Eight hours after being examined, she reported photopsias and a new visual field defect in the right eye . Visual acuity was 20/40, pinhole 20/20 in the right eye, with restriction of visual field by confrontation. Dilated fundus examination revealed retinal whitening in all quadrants with sparing of the fovea along the distribution of a perfused cilioretinal artery. Optical coherence tomography showed an intact foveal depression with inner retinal layer hyperreflectivity outside the region of the perfused cilioretinal artery. Fluorescein angiography revealed sectoral nonperfusion of the posterior pole with macular sparing along the patent cilioretinal artery. Hypercoagulable workup, carotid imaging, and magnetic resonance imaging of the brain were unremarkable. CONCLUSION: This is the first report of a central retinal artery occlusion with cilioretinal artery sparing occurring on postoperative Day 1 after laser-assisted in situ keratomileusis surgery.

Glass intraocular foreign body removal with a nitinol stone basket.

PURPOSE: Glass intraocular foreign bodies (IOFBs) complicate up to 14% of all IOFB cases and require specialized instruments for removal. We present a case of ocular trauma with two large glass IOFBs removed using a nitinol stone basket (NSB) designed for kidney stone extraction in the ureter and calyces. OBSERVATIONS: An adult male suffered a restrained motor vehicle accident. Radiographic computed tomography identified a 9-mm polygonal IOFB within the posterior segment of the right eye. A staged procedure was performed with repair of the ruptured globe followed by 23-gauge pars plana vitrectomy, pars plana lensectomy, and removal of the IOFBs using a NSB. CONCLUSION: At post-operative month one, visual acuity was correctable to 20/60. The retina remained attached and the patient was recovering without complication. IMPORTANCE: Large glass IOFBs are poorly gripped by standard ophthalmic forceps due to their smooth surface, large size, and irregular shape. The NSB is an effective instrument for controlled removal of glass IOFBs. Further customized design may adapt this device for additional intraocular procedures.

Assessment of Global and Local Alterations in Retinal Layer Thickness in Ins2 (Akita) Diabetic Mice by Spectral Domain Optical Coherence Tomography.

PURPOSE/AIM: The Ins2 (Akita) mouse is a spontaneous diabetic mouse model with a heterozygous mutation in the insulin 2 gene that results in sustained hyperglycemia. The purpose of the study was to assess global and local retinal layer thickness alterations in Akita mice by analysis of spectral domain optical coherence tomography (SD-OCT) images. MATERIALS AND METHODS: SD-OCT imaging was performed in Akita and wild-type mice at 12 and 24 weeks of age. Inner retinal thickness (IRT), outer retinal thickness (ORT), total retinal thickness (TRT), and photoreceptor outer segment length (OSL) were measured. Mean global thickness values were compared between Akita and wild-type mice. Local thickness variations in Akita mice were assessed based on normative values in wild-type mice. RESULTS: Akita mice had higher blood glucose levels and lower body weights (p < 0.001). On average, IRT, ORT, and TRT were approximately 2% lower in Akita mice than in wild-type mice (p ≤ 0.02). In Akita mice, the percent difference between retinal areas with thickness below and above normative values for IRT, ORT, and TRT was 22%, 32%, and 38%, respectively. CONCLUSIONS: These findings support the use of the Akita mouse model to study the retinal neurodegenerative effects of hyperglycemia.

Enface Thickness Mapping and Reflectance Imaging of Retinal Layers in Diabetic Retinopathy.

PURPOSE: To present a method for image segmentation and generation of enface thickness maps and reflectance images of retinal layers in healthy and diabetic retinopathy (DR) subjects. METHODS: High density spectral domain optical coherence tomography (SDOCT) images were acquired in 10 healthy and 4 DR subjects. Customized image analysis software identified 5 retinal cell layer interfaces and generated thickness maps and reflectance images of the total retina (TR), inner retina (IR), outer retina (OR), and the inner segment ellipsoid (ISe) band. Thickness maps in DR subjects were compared to those of healthy subjects by generating deviation maps which displayed retinal locations with thickness below, within, and above the normal 95% confidence interval. RESULTS: In healthy subjects, TR and IR thickness maps displayed the foveal depression and increased thickness in the parafoveal region. OR and ISe thickness maps showed increased thickness at the fovea, consistent with normal retinal anatomy. In DR subjects, thickening and thinning in localized regions were demonstrated on TR, IR, OR, and ISe thickness maps, corresponding to retinal edema and atrophy, respectively. TR and OR reflectance images showed reduced reflectivity in regions of increased thickness. Hard exudates appeared as hyper-reflective spots in IR reflectance images and casted shadows on the deeper OR and ISe reflectance images. The ISe reflectance image clearly showed the presence of focal laser scars. CONCLUSIONS: Enface thickness mapping and reflectance imaging of retinal layers is a potentially useful method for quantifying the spatial and axial extent of pathologies due to DR.

Hemorrhagic Retinopathy after Spondylosis Surgery and Seizure.

PURPOSE: To report bilateral hemorrhagic retinopathy in an adult female subject after lumbar spinal surgery and seizure. CASE REPORT: A 38-year-old woman presented with bilateral blurry vision and spots in the visual field. The patient had lumbar spondylosis surgery that was complicated by a dural tear with persistent cerebrospinal fluid leak. Visual symptoms started immediately after witnessed seizure-like activity. At presentation, visual acuity was 20/100 and 20/25 in the right and left eye, respectively. Dilated fundus examination demonstrated bilateral hemorrhagic retinopathy with subhyaloid, intraretinal, and subretinal involvement. At 4-month follow-up, visual acuity improved to 20/60 and 20/20 in the right and left eye, respectively. Dilated fundus examination and fundus photography showed resolution of retinal hemorrhages in both eyes. CONCLUSIONS: The first case of bilateral hemorrhagic retinopathy after lumbar spondylosis surgery and witnessed seizure in an adult was reported. Ophthalmic examination may be warranted after episodes of seizure in adults.

Comparison of primary open angle glaucoma patients in rural and urban Ghana.

PURPOSE: To compare the clinical features of glaucoma patients who present at a rural hospital in North Eastern Ghana and an urban hospital in the capital city of Accra. METHODS: This is a multi-center retrospective case series involving records of newly diagnosed glaucoma patients with emphasis on primary open angle glaucoma (POAG). Information collected included basic demographic data, intraocular pressures and optic disc measurements. RESULTS: A total of 949 patients (437 rural; 512 urban; 1868 eyes) were included. Rural vs. urban comparisons, respectively: mean age, 53.2 ± 16.3 vs. 54.5 ± 16.4 years; male: female ratio, 3:2 vs. 1:1; POAG, 78.1% vs. 50.6%; POAG suspect, 10.3% vs. 41.9%; IOP, 39.2 ± 7.1 vs. 31.8 ± 7.3 mmHg; bilateral blindness, 34.1% vs. 17.5%; uniocular blindness, 52.2% vs. 32.9%. Females at the rural hospital were twice as likely to present blind in at least one eye (OR 2.04, CI 1.36 - 3.07, p < 0.001). CONCLUSIONS: Patients with POAG at the rural hospital present with more advanced disease characteristics.

Morphometric analysis of aqueous humor outflow structures with spectral-domain optical coherence tomography.

PURPOSE: To describe morphometric details of the human aqueous humor (AH) outflow microvasculature visualized with 360-degree virtual castings during active AH outflow in cadaver eyes and to compare these structures with corrosion casting studies. METHODS: The conventional AH outflow pathways of donor eyes (n = 7) and eyes in vivo (n = 3) were imaged with spectral-domain optical coherence tomography (SD-OCT) and wide-bandwidth superluminescent diode array during active AH outflow. Digital image contrast was adjusted to isolate AH microvasculature, and images were viewed in a 3D viewer. Additional eyes (n = 3) were perfused with mock AH containing fluorescent tracer microspheres to compare microvasculature patterns. RESULTS: Observations revealed components of the conventional outflow pathway from Schlemm's canal (SC) to the superficial intrascleral venous plexus (ISVP). The superficial ISVP in both our study and corrosion casts were composed of interconnected venules (10-50 µm) forming a hexagonal meshwork. Larger radial arcades (50-100 µm) drained the region nearest SC and converged with larger tortuous vessels (>100 µm). A 360-degree virtual casting closely approximated corrosion casting studies. Tracer studies corroborated our findings. Tracer decorated several larger vessels (50-100 µm) extending posteriorly from the limbus in both raw and contrast-enhanced fluorescence images. Smaller tracer-labeled vessels (30-40 µm) were seen branching between larger vessels and exhibited a similar hexagonal network pattern. CONCLUSIONS: SD-OCT is capable of detailed morphometric analysis of the conventional outflow pathway in vivo or ex vivo with details comparable to corrosion casting techniques.

Comparison of moderate and advanced glaucoma patients in Ghana.

PURPOSE: To compare moderate and advanced glaucoma patients in Ghana. METHODS: A retrospective cross-sectional study of 164 patients with primary open-angle glaucoma (POAG) were separated into moderate and advanced glaucoma groups. Definitions of moderate and advanced POAG were derived from International Geographical and Epidemiologic Ophthalmology criteria and included clinical assessment of optic disc atrophy and Humphrey automated perimetry. Data were collected at the patient's first visit prior to initiation of therapy. Eligible POAG patients included those ≥30 years old with reliable Humphrey visual field (HVF) results, no past POAG diagnosis, treatment, or evidence of a secondary cause for glaucoma. Main outcome measures included comparisons of intraocular pressure (IOP), cup-to-disk ratio (CDR), best corrected visual acuity (VA), age, Humphrey mean deviation (MD), and pattern standard deviation (PSD). RESULTS: Of 164 charts reviewed, 90 (54.9%) advanced and 74 (45.1%) moderate POAG patients were compared. Mean age was 59.36 versus 55.53 years, respectively. Significant differences in IOP, CDR, CDR asymmetry, and HVF results were described. IOP > 30 mmHg was associated with CDR > 0.7 and MD greater than -12 dB in both eyes. CONCLUSION: Significant differences were found between IOP, CDR, MD and PSD values. HVF is predictive of pretreated IOP, CDR, and severity of POAG and it is strongly encouraged as part of the standard glaucoma work up in all Ghanaian patients.