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PubMed2006

Neural and optical limits to visual performance in myopia.

We investigated the relative importance of neural and optical limitations to visual performance in myopia. A number of visual performance measures were made on all or subsets of 121 eyes of emmetropic and myopic volunteers aged 17-35 years. These tests included visual measures that are mainly neurally limited (spatial summation out to +/-30 degrees in the horizontal visual field and resolution acuity out to +/-10 degrees in the horizontal visual field) and central ocular aberrations. We found that myopia affected the neurally limited tests, but had little effect on central higher order aberration. The critical area for spatial summation increased in the temporal visual field at 0.03 log units/dioptre of myopia. Resolution acuity decreased at approximately 0.012 log units/dioptre of myopia. Losses of visual function were slightly greater in the temporal than in the nasal visual field. The observed visual deficit in myopia can be explained by either global retinal expansion with some post-receptor loss (e.g. ganglion cell death) or a posterior polar expansion in which the point about which expansion occurs is near the centre of the previously emmetropic globe.

Adolescent↗
PubMed2000

Three-dimensional observations of developing macular holes.

PURPOSE: To describe the morphologic features of idiopathic macular holes and vitreous traction during macular hole evolution. METHODS: We prospectively examined 89 eyes of 82 patients with idiopathic macular holes (stage 1, 15 eyes; stage 2, 16 eyes; stage 3, 50 eyes; stage 4, eight eyes) using optical coherence tomography. In addition to optical coherence tomography, scanning laser ophthalmoscopy was performed in all 15 eyes with stage 1 hole, six of 16 eyes with stage 2, and 19 of 50 eyes with stage 3. RESULTS: In stage 1 eyes, optical coherence tomography revealed retinal split or cystic changes at the fovea in 11 of 15 eyes (73%) and foveal retinal detachment in four eyes (27%). Two eyes with foveal cysts progressed to stage 2, and one developed a stage 3 hole. In one eye with retinal detachment, the detached retina thinned and developed dehiscence. Optical coherence tomography showed a vitreous cortex that was detached in the perifoveal area but attached on the fovea in 11 of the 15 stage 1 eyes. In stage 2 macular holes, retinal tissue extending from the perifoveal retina formed a flap. Scanning laser ophthalmoscopy demonstrated intraretinal radiating striae, which corresponded to a foveal cyst or perifoveal cystic changes. CONCLUSIONS: Macular holes start as retinal splits or foveal cysts in most cases. The anterior wall of the cyst serves as a flap in stage 2 and an operculum in stage 3 holes. Radiating striae correspond to retinal splits or cysts and presumably represent an elevation of Henle fiber. In a few macular holes, foveal detachment is the initial change. The detached retina thins and eventually develops a hole. In both courses, anterior traction of the slightly detached vitreous cortex appears to be a major contributing factor to macular hole formation.

Aged↗
PubMed2000

Tomographic features of early macular hole closure after vitreous surgery.

PURPOSE: To report the optical coherence tomographic features of macular hole closure in the first months after vitreous surgery. METHODS: We studied prospectively the tomographic features of 28 eyes (28 patients) with idiopathic macular holes before and after vitreous surgery by optical coherence tomography. We compared the best-corrected visual acuity levels with the postoperative tomographic features. RESULTS: The 25 eyes with successfully sealed macular holes had one of two tomographic features within 1 month postoperatively: simple closure (normal foveal configuration) in 14 eyes (56%) or a bridge formation at the fovea that mimicked a foveal retinal detachment in 11 eyes (44%). It took an average of 2.0 months (range, 0.8 to 3.5 months) for the bridge tissue to attach to the retinal pigment epithelium. Best-corrected visual acuity quickly improved in the former group; visual improvement began 1 month after attachment of the bridge tissue in the latter group. A closed hole reopened 4 months postoperatively in one eye with a bridge formation. CONCLUSIONS: Idiopathic macular holes have one of two patterns early after surgical closure, simple closure or a bridge formation. Visual improvement starts after the fovea assumes a normal configuration. The bridge formation appears to reflect an early phase and fragile condition in the anatomic closure of macular holes.

Aged↗
PubMed2000

Optical coherence tomography patterns of choroidal osteoma.

PURPOSE: To determine the optical coherence tomographic images that are commonly observed in eyes with choroidal osteoma (choroidal ossification). METHODS: Three patients with choroidal osteoma were examined by optical coherence tomography. RESULTS: We found two optical coherence tomographic patterns in the eyes with choroidal osteoma. First, multiple tracks of high refractivity were present posterior to the tumor lesion. Second, thick and irregular plate-like, high-signal intensity areas were present in the choroid in the region of the tumor. CONCLUSIONS: Optical coherence tomography can be useful in the diagnosis of choroidal osteoma.

Adult↗
PubMed2000

Amsler grid examination and optical coherence tomography of a macular hole caused by accidental Nd:YAG laser injury.

PURPOSE: To compare a macular hole from accidental Nd:YAG laser injury with idiopathic macular holes. METHODS: Case report. In a 24-year-old man with accidental Nd:YAG laser injury, right eye, Amsler grid testing and optical coherence tomography were performed. RESULTS: Nd:YAG laser injury was responsible for a macular hole about 700 microm in diameter. The visual acuity was 20/100. Amsler grid testing displayed a central scotoma with no surrounding distortion. Optical coherence tomography showed a defect in all retinal layers at the macula. CONCLUSION: The scotoma caused by Nd:YAG laser injury is not surrounded by distortion; the hole is produced by the defect of all retinal layers. In contrast, idiopathic macular holes generally produce a pincushion pattern on Amsler grid testing and have no tissue loss.

Accidents, Occupational↗
PubMed2000

Optical coherence tomography of idiopathic macular epiretinal membranes before and after surgery.

PURPOSE: To examine the preoperative and postoperative anatomical features of the macula using optical coherence tomography in patients who underwent surgery for epiretinal membrane and to correlate these features with functional results. METHODS: In a noncomparative interventional series, 62 eyes of 62 consecutive patients operated on for an idiopathic epiretinal membrane were followed up using a standardized protocol. Preoperative and postoperative examination included best-corrected visual acuity using an Early Treatment Diabetic Retinopathy Study chart, biomicroscopy of the fundus with a contact lens, fundus photography with blue and green filters, fluorescein angiography, and optical coherence tomography. RESULTS: Median preoperative visual acuity was 20/60 (range, 20/32 to 20/320). Median postoperative visual acuity was 20/40 (range, 20/20 to 20/160). Fifty-one eyes (82%) obtained visual acuity of 20/50 or better. Preoperatively, all eyes had increased macular thickness (mean, 419 +/- 105 microm; range, 265.5 to 689 microm), with disappearance of the foveal pit. An epiretinal membrane was visible on optical coherence tomography scans in 26 cases (42%). Intraretinal cystic spaces were present in the thickened macular tissue in 15 cases but corresponded to cystoid macular edema on fluorescein angiography in only three. Postoperatively, mean macular thickness decreased to 300 +/- 65 microm (range, 185 to 511 microm) but returned to normal in only three eyes. The foveal pit reappeared in 20 eyes. Preoperatively, visual acuity correlated with macular thickness (r = 0.56, P <.0001), but not postoperatively (r = 0.12, P =.37). CONCLUSION: Macular thickness decreases after epiretinal membrane surgery, but the macular profile rarely returns to normal. However, this does not preclude satisfactory improvement of visual acuity.

Aged↗
PubMed2000

Optical coherence tomography in uveitis patients.

PURPOSE: To evaluate optical coherence tomography in allergy-prone uveitis patients. METHODS: Thirty-four patients (43 eyes) with posterior uveitis (31 eyes) and intermediate uveitis (12 eyes) were evaluated by fluorescein angiography, indocyanine green angiography, and optical coherence tomography. Follow-up examinations used optical coherence tomography in allergy-prone patients. RESULTS: Optical coherence tomography identified epiretinal membranes, which were removed surgically (three eyes); persistent cystoid macular edema, which resolved with cytotoxic treatment (12 eyes); and juxtafoveolar membranes, which were treated by diode laser (six eyes) and excision (two eyes). CONCLUSION: Optical coherence tomography may provide useful information on complications developing in uveitis patients.

Adult↗
PubMed2000

Optical coherence tomograghy to confirm early closure of macular holes.

PURPOSE: To report that optical coherence tomography as early as 24 hours after macular hole surgery shows anatomic configuration of the closed macular holes. METHOD: In a prospective study, seven eyes of seven consecutive patients with stage 3 or 4 idiopathic macular hole underwent surgery. Optical coherence tomography was performed preoperatively and at 24, 48, and 72 hours after the surgery. RESULTS: Optical coherence tomography images could be obtained on four out of the seven eyes at 24 hours after surgery. These images showed anatomic configuration of the closed macular holes. Surgical success was confirmed in all of the eyes when the gas was completely absorbed. CONCLUSION: Optical coherence tomography revealed anatomic configuration of surgically closed macular holes within 24 hours after successful surgery.

Aged↗
PubMed2000

Corneal optical coherence tomography before and immediately after excimer laser photorefractive keratectomy.

PURPOSE: To investigate the representation of the corneal structure with optical coherence tomography before and immediately after excimer laser photorefractive keratectomy. METHODS: Twenty-four eyes of 24 patients with myopia and myopic astigmatism were prospectively studied. The corneal thickness and the corneal profile were assessed with slit-lamp-adapted optical coherence tomography preoperatively and immediately after excimer laser photorefractive keratectomy. RESULTS: The attempted mean spherical equivalent of the refractive corrections was -6.7 +/- 3.6 (mean +/- SD) diopters with a mean calculated stromal ablation depth of 91 +/- 38 microm. The corneal optical coherence tomography was reproducible in all patients, demonstrating a mean decrease of central corneal thickness after epithelial debridement and excimer laser photorefractive keratectomy of 118 +/- 45 microm. The comparison of the calculated stromal ablation depth and the corneal thickness changes determined by corneal optical coherence tomography revealed a significant linear relationship with a correlation coefficient of 0.88 (P <.001). The flattening of the corneal curvature was confirmed in all patients with the optical coherence tomography system and correlated with the attempted refractive correction (r =.82, P <.001). CONCLUSIONS: The slit-lamp-adapted optical coherence tomography system presented in this study allowed noncontact, cross-sectional, and high-resolution imaging of the corneal configuration. This initial clinical evaluation demonstrated that corneal optical coherence tomography could be a promising diagnostic modality to monitor corneal changes of thickness and curvature before and after excimer laser photorefractive keratectomy.

Adult↗
PubMed2000

Tomographic features of a lamellar macular hole formation and a lamellar hole that progressed to a full-thickness macular hole.

PURPOSE: To report optical coherence tomography of a lamellar macular hole and a lamellar macular hole that progressed to a full-thickness macular hole. METHODS: Case Reports. RESULTS: Case 1. In the right eye of a 66-year old man, a lenticular-shaped split was present in the inner neurosensory retina corresponding to the fovea. Three months later, an operculum formed anterior to the fovea where the retina was attenuated. Case 2. In the left eye of a 58-year old woman, a foveal cyst was seen in the inner neurosensory retina and the inner wall of the cyst was elevated, where a slightly detached posterior vitreous cortex was attached. One month later, the inner wall was operculated, leaving a thin foveal bottom. Four months later, the hole progressed to a full-thickness macular hole. CONCLUSION: Lamellar macular hole appears to form when the inner wall of a split or cyst in the neurosensory retina at the fovea is avulsed by vitreous traction.

Aged↗
PubMed2000

Optical coherence tomography of melanocytoma.

PURPOSE: To evaluate the use of optical coherence tomography in differentiating between melanocytoma and choroidal melanoma. METHODS: Case reports. Three consecutive patients with melanocytoma were scanned using optical coherence tomography. RESULTS: Optical coherence tomography showed lesions with a high reflectance signal anteriorly and optical shadowing behind, corresponding to the melanocytomas. The high signal was continuous with the retinal nerve fiber layer, consistent with known growth patterns of melanocytoma. CONCLUSION: Optical coherence tomography may be useful in differentiating melanocytoma from choroidal melanocytic lesions.

Adult↗
PubMed2001

Tomographic findings of foveal hard exudates in diabetic macular edema.

PURPOSE: To report the intraretinal location of foveal hard exudates after vitrectomy to treat diabetic macular edema and to evaluate the visual outcome. METHODS: In a prospective study, the tomographic features of 11 eyes (8 patients) with diabetic macular edema were evaluated with optical coherence tomography after vitrectomy. The intraretinal location of hard exudates at the fovea (anatomic foveola) and the relationship with visual acuity were investigated. RESULTS: With optical coherence tomography, hard exudates were observed as highly reflective spots in the cross-sectional images. In six of 11 eyes (54.5%), the hard exudates were in the inner portion of the neurosensory retina; the final best-corrected visual acuity averaged 20/70 in the six eyes. In the remaining five eyes (45.5%), hard exudates were deposited not only in the neurosensory retina but also in the subretinal space. In optical coherence tomographic images, subretinal hard exudates were observed as highly reflective plaques, which were slightly elevated over the retinal pigment epithelium. The five eyes developed a serous retinal detachment at the fovea before or after vitrectomy. Subretinal hard exudates bridged the detached neurosensory retina and the retinal pigment epithelium in two eyes. The average final visual acuity level in the five eyes was 20/300. The visual outcome was significantly worse in five eyes with subretinal hard exudates than in six eyes with an intraretinal one (P <.05, Wilcoxon rank sum tests). CONCLUSIONS: If serous retinal detachment develops before or after vitrectomy for diabetic macular edema, hard exudates tend to accumulate not only in the neurosensory retina but also in the subretinal space. The visual prognosis is worse in cases of subretinal exudation.

Aged↗
PubMed2000

Optical coherence tomographic features of idiopathic submacular choroidal neovascularization.

PURPOSE: To clarify the morphologic features of idiopathic submacular choroidal neovascularization using optical coherence tomography. METHODS: Using optical coherence tomography, we prospectively examined 17 consecutive eyes (17 patients; eight men, nine women; mean age +/- SD, 36.0 +/- 9.3 years) with idiopathic submacular choroidal neovascularization. During the follow-up period (mean +/- SD, 7.5 +/- 3.8 months), we repeated optical coherence tomography in 15 eyes; optical coherence tomography was performed only at the initial examination in two eyes that underwent submacular surgery. RESULTS: Choroidal neovascularization was observed in the subsensory retinal space anterior to the retinal pigment epithelium as a highly or moderately reflective mass, which protruded from the retinal pigment epithelium in 13 of 17 eyes (protruding type). In four eyes, choroidal neovascularization was a highly reflective fusiform mass at the level of the retinal pigment epithelium and choriocapillaris (fusiform type). During the follow-up period, choroidal neovascularization regressed and the protruding mass became a highly reflective fusiform mass in 10 of 11 eyes with the protruding type that underwent repeated examination. In three of the 10 eyes, during 5 to 10 months from initial examination, the choroidal neovascularization was exacerbated and it again protruded into the subsensory retinal space anterior to the retinal pigment epithelium. Four eyes with the fusiform type remained the same throughout the follow-up period. The overlying retina was thickened and had low reflectivity in all 17 eyes at the initial examination. Optical coherence tomography identified subretinal fluid in only 11 of the 13 eyes with protruding type choroidal neovascularization. CONCLUSIONS: Optical coherence tomography confirmed subsensory retinal location of idiopathic submacular choroidal neovascularization anterior to the retinal pigment epithelium. Protruding choroidal neovascularization transforms to fusiform tissue at the level of the retinal pigment epithelium during the process of regression. Sensory retinal edema was always associated with choroidal neovascularization.

Adult↗
PubMed2001

Perimetric sensitivity and retinal thickness in eyes with macular edema resulting from branch retinal vein occlusion.

PURPOSE: To document and study the relationship between perimetric sensitivity and retinal thickness at the foveal and parafoveal points in eyes with macular edema associated with branch retinal vein occlusion. METHODS: A prospective study was performed using the central 10-2 Humphrey perimetry program and optical coherence tomography. Seventeen eyes with branch retinal vein occlusion were eligible showing macular edema without macular nonperfusion or massive retinal hemorrhage. RESULTS: The sensitivity and retinal thickness were significantly correlated at the fovea (r = -0.629, P =.006) as well as 1 (r = -0.656, P <.0001) and 3 (r = -0.885, P <.0001) degrees apart from the fovea. The visual acuity that is expressed as a logarithm of the minimum angle of resolution (LogMAR) also correlated with retinal thickness (r = 0.591, P =.011). CONCLUSION: The increased retinal thickness resulting from macular edema is closely correlated with retinal sensitivity as measured by automated static perimetry both at the fovea and parafovea. Measuring the retinal thickness using optical coherence tomography may be useful in monitoring macular edema in eyes with branch retinal vein occlusion.

Adult↗
PubMed2001

Serous retinal detachment and cystoid macular edema in hypotony maculopathy.

PURPOSE: To report the foveal structural findings of hypotony maculopathy imaged with optical coherence tomography. METHODS: Case report of a 39-year-old white woman with a 20 year history of uveitis, who underwent pars plana vitrectomy and pars plana Baerveldt implant for intractable glaucoma. Four months postoperatively, decreased vision and hypotony maculopathy ensued. Optical coherence tomographic (OCT) images were taken horizontally through the macula. RESULTS: OCT demonstrated large intraretinal cysts, serous macular detachment, and choroidal folds, which resolved upon resolution of hypotony. CONCLUSION: Cystic macular changes and serous macular detachment can be prominent features of hypotony maculopathy.

Adult↗
PubMed2001

Vitreoretinal traction maculopathy caused by retinal diseases.

PURPOSE: To study the morphological findings of vitreoretinal traction maculopathy caused by retinal vascular diseases and their changes after vitrectomy. METHODS: Optical coherence tomographic images of 13 eyes of 12 cases were evaluated before and after vitrectomy. RESULTS: The tractional force appeared to be mainly tangential with a possible anterior vector in 11 eyes, and mainly in the anterior direction in 2 eyes. After surgery, the increased foveal thickness decreased markedly in all eyes, and visual acuity improved in 8 eyes. CONCLUSION: Preoperative optical coherence tomographic examination can reveal the fine structure of vitreoretinal separations and adherences caused by retinal vascular diseases. These observations permitted better surgical planning and results.

Adult↗
PubMed2001

Macular traction detachment and diabetic macular edema associated with posterior hyaloidal traction.

PURPOSE: To review the clinical, photographic, fluorescein angiographic, and optical coherence tomographic findings in patients with the diabetic macular traction and edema (DMTE) associated with posterior hyaloidal traction (PHT). METHODS: We performed a prospective review of nine eyes of nine patients with diabetic macular edema (DME) and PHT on clinical examination. The patients had a comprehensive ophthalmic history and examination, color photographs, fluorescein angiography, and optical coherence tomography (OCT). RESULTS: All patients had diabetic retinopathy and DME. Of the nine eyes, eight patients had previous focal or grid photocoagulation. All nine eyes had a thickened, taut, glistening posterior hyaloid on clinical biomicroscopic examination with no posterior vitreous separation. Fluorescein angiography was performed on seven eyes, and all had early hyperfluorescence with deep, diffuse, late leakage in the macular area consistent with DMTE associated with PHT. Optical coherence tomography scans of the macular region revealed retinal thickening in all eyes with a mean retinal thickness of 556.9 +/- 114.7 microns. In addition, eight of the nine eyes had a shallow macular traction detachment associated with PHT. CONCLUSION: Eyes with DME associated with PHT may have a shallow, subclinical, macular detachment. Optical coherence tomography may be useful in evaluating patients with DME to see if a macular detachment is present.

Aged↗
PubMed2001

Optical coherence tomography evaluation of idiopathic macular hole treatment by gas-assisted posterior vitreous detachment.

PURPOSE: To report a case of idiopathic macular hole, with vitreoretinal traction confirmed by optical coherence tomography that was successfully treated by a single intravitreous perfluoropropane (C(3)F(8)) gas bubble injection. METHODS: Case report. A 65-year-old patient with idiopathic macular hole (stage 2, one eye) received an intravitreous gas injection and was prospectively followed with optical coherence tomography. RESULTS: A complete posterior vitreous detachment was achieved within 6 weeks after gas injection. Visual acuity improved from 20/80 to 20/25 by 10 months of follow-up. Optical coherence tomography disclosed vitreoretinal traction release and macular hole closure. No complications were related to the procedure. CONCLUSION: This simple procedure can assist a complete posterior vitreous detachment with relief of the hyaloid-foveolar traction, facilitating macular hole closure.

Aged↗