The comparative histologic effects of subthreshold 532- and 810-nm diode micropulse laser on the retina.

PURPOSE: Therapeutic retinal laser photocoagulation can damage the neurosensory retina and cause iatrogenic visual impairment. Subthreshold micropulse photocoagulation may decrease this risk by selective tissue treatment. The aim of this study was to compare subthreshold 810-nm diode micropulse laser and subthreshold 532-nm micropulse laser on the retina by histologic examination and differential protein expression. METHODS: Fourteen Dutch-belted rabbits received subthreshold 810-nm diode micropulse laser photocoagulation in their right eye and subthreshold 532-nm micropulse laser photocoagulation in their left eye. Histology and immunohistochemical detection of stromal cell-derived factor-1 (SDF-1), ß-actin, vascular endothelial growth factor (VEGF), glial fibrillary acidic protein (GFAP), and insulin-like growth factor 1 (IGF-1) were analyzed 12 hours, 3 days, 14 days, and 28 days post-laser photocoagulation. RESULTS: Histologically, all time points produced a similar degree of retinal disruption in both wavelengths. Immunohistochemically, SDF-1 expression was greatest at the 12-hour time point and decreased thereafter. SDF-1, VEGF, and ß-actin up-regulation was detected at early time points in both the 810- and 532-nm micropulse laser-treated animals. CONCLUSIONS: Subthreshold micropulse retinal laser photocoagulation caused equivalent histologic changes from both 532- and 810-nm diode lasers. Differential protein expression was not evident between the different laser conditions.

High-resolution Fourier-domain optical coherence tomography of choroidal neovascular membranes associated with age-related macular degeneration.

PURPOSE: To investigate the use of high-resolution Fourier-domain optical coherence tomography (Fd-OCT) to image choroidal neovascular membranes (CNVMs) associated with exudative age-related macular degeneration (eAMD). METHODS: An Fd-OCT instrument with axial resolution of 4 to 4.5 microm and transverse resolution of 10 to 15 microm was used to image 21 eyes (19 subjects) with newly diagnosed eAMD. A raster series of 100 B-scans separated by 60 microm was used to study the growth pattern of CNVM and associated morphologic changes. CNVM size was determined using 250 to 300 serial virtual C-scans of reconstructed three-dimensional macular volume. RESULTS: A highly reflective subretinal and/or subretinal pigment epithelial (RPE) lesion that co-localized with the CNVM seen on fluorescein angiography was detected in all eyes by Fd-OCT. Although a combined subretinal and sub-RPE growth pattern of various degrees was noted in 15 (71%) eyes, a statistically significant difference in the distribution of growth pattern was noted when classic CNVM was compared with occult CNVM (chi(2) = 10.4, df = 2, P < 0.005). Classic lesions had >90% subretinal growth pattern, whereas occult lesions had a more variable growth pattern. Angiographic CNVM size correlated with size on Fd-OCT but correlation was better for classic CNVM (classic, r = 0.99, P < 0.0001; nonclassic, r = 0.78, P < 0.001). CONCLUSIONS: Fd-OCT is a promising potential alternative modality to visualize CNVM with AMD. Angiographic lesion size and type correlated with growth pattern and size of CNVM on Fd-OCT, with correlation being stronger for classic lesions.

Microcystoid maculopathy associated with tamoxifen use diagnosed by high-resolution fourier-domain optical coherence tomography.

PURPOSE: To describe a case of microcystoid maculopathy diagnosed by high-resolution Fourier-domain optical coherence tomography (Fd-OCT) in a patient treated with tamoxifen who had previously unexplained vision loss. METHODS: Report of a case of a 66-year-old woman treated with tamoxifen for 4 years who had progressive unexplained vision loss in the left eye for 2 years. RESULTS: Visual acuity was 20/25 in the right eye and 20/70 in the left eye. Findings of funduscopy and fluorescein angiography were unremarkable except for minimal pigment alteration in the macula in the left eye. Stratus OCT showed possible microcystoid changes in the fovea in both eyes. Fd-OCT revealed scattered intraretinal microcystoid changes and patches of focal loss of photoreceptors in the macula in both eyes with foveal involvement in the left eye. Full-field electroretinogram was normal. Multifocal electroretinogram showed some decreased response in the peripheral macula and borderline low foveal response in both eyes. CONCLUSION: Microcystoid maculopathy associated with tamoxifen use can be diagnosed by Fd-OCT in a normal appearing fundus. It can present as unexplained vision loss.

Neuroretinitis associated with serologies positive for bartonella henselae and borrelia burgdorferi.

PURPOSE: To describe a patient with neuroretinitis with features of both cat-scratch disease and Lyme disease who had serologies positive for both Bartonella henselae and Borrelia burgdorferi. METHODS: Case report of a single individual undergoing diagnostic testing and treatment for neuroretinitis. RESULTS: A 47-year-old woman developed acute painless loss of vision and was found to have neuroretinitis. Diagnostic workup yielded serologies positive for both B. henselae and B. burgdorferi. The patient was treated with oral antibiotics for coverage of both etiologies, and her condition improved. CONCLUSION: Serologies positive for both B. henselae and B. burgdorferi can be obtained in the workup of neuroretinitis. Clinicians should be aware and use clinical judgment in guiding their diagnosis and treatment of neuroretinitis.

High resolution Fourier-domain optical coherence tomography of retinal angiomatous proliferation.

PURPOSE: To study the anatomic details of retinal angiomatous proliferation (RAP) in patients with age-related macular degeneration (AMD) using high-resolution Fourier-domain optical coherence tomography (Fd-OCT) and its three-dimensional reconstructions. METHODS: A Fd-OCT instrument was used to image five patients clinically diagnosed with RAP. A series of 100 raster-scanned B-scans centered over the macula was registered and rendered as a three-dimensional volume. These retinal structures were analyzed for anatomic details of the RAP lesions. RESULTS: The RAP lesion could be identified within the retina on Fd-OCT in all five cases. Fd-OCT images of the first four cases revealed areas of intraretinal neovascularization (IRN) in the deep retina adjacent to a pigment epithelial detachment (PED). There was neovascular proliferation anteriorly and posteriorly through a break in the retinal pigment epithelium (RPE). In three of the four cases, Bruch membrane remained intact. There was no identifiable choroidal neovascularization (CNV). The fifth case had both subretinal and sub-RPE neovascular membranes without a PED. CONCLUSION: Fd-OCT provides unprecedented in vivo detail of the anatomy of RAP lesions that nearly resembles histologic specimens. This study suggests that the initial neovascular process in RAP can originate either within the retina or in the sub-RPE space.

Vitrectomy for stage 1 macular holes identified by optical coherence tomography.

BACKGROUND AND OBJECTIVE: To describe a series of patients with decreased vision secondary to stage 1 macular hole confirmed by optical coherence tomography (OCT) that failed to spontaneously resolve with observation. To determine whether current surgical techniques can prevent progression to a full-thickness macular hole and lead to improved visual acuity. PATIENTS AND METHODS: Retrospective, comparative case series presenting patient demographics, duration of symptoms, timing of surgery, preoperative and postoperative vision, and clinical outcome based on examination and OCT. RESULTS: Five eyes of five patients with stage 1 macular holes identified on OCT required surgical repair. All eyes showed anatomic closure and lack of progression to a full-thickness hole confirmed by OCT after one procedure. Mean preoperative visual acuity was 20/102 (range, 20/50 to 20/200) and mean postoperative visual acuity was 20/52 (range, 20/25 to 20/200). Average improvement for all five eyes was 3 Snellen lines, with four of the five (80%) improving 5 lines each. CONCLUSION: In symptomatic eyes with stage 1 macular holes that fail to spontaneously resolve with observation, vitrectomy with intraocular gas tamponade may prevent progression to a full-thickness hole and lead to improved visual acuity.