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M W Ulbig

Publications and source records attributed to M W Ulbig.

At least 19 recordsLinked to original sources
PubMed2002

Macular hole size as a prognostic factor in macular hole surgery.

BACKGROUND/AIM: In 1991 there was a series of successful closures of a macular hole after vitrectomy and membrane peeling. Today this technique has become a standard procedure. The aim of this study was to evaluate the role of optical coherence tomography in diagnosing and staging, as well as in predicting, the functional and anatomical outcome after macular hole surgery. METHOD: In a prospective study 94 consecutive patients (20 male, 74 female) with a mean age of 67.6 (SD 6.0) years and a macular hole stage II (n = 8), III (n = 72), and IV (n = 14) according to the classification by Gass were examined with optical coherence tomography (OCT) before pars plana vitrectomy. Macular hole diameters were determined at the level of the retinal pigment epithelium (base diameter) and at the minimal extent of the hole (minimum diameter). Calculated hole form factor (HFF) was correlated with the postoperative anatomical success rate and best corrected visual acuity. The duration of symptoms was correlated with base and minimum diameter of the macular hole. RESULTS: In eyes without anatomical closure of the macular hole after one surgical approach (13/94) the base diameter (p1) and the minimum diameter (p2) were significantly larger than in cases with immediate postsurgical closure (p1 = 0.003; p2 = 0.028). There was a significant negative correlation between both the base and the minimum diameter of the hole and the postoperative visual function (p1 = 0.016; p2 = 0.002). In all patients with HFF >0.9 the macular hole was closed following one surgical procedure, whereas in eyes with HFF <0.5 anatomical success rate was 67%. Better postoperative visual outcome correlated with higher HFF (p = 0.050). There was no significant correlation between the duration of symptoms and base or minimum diameters (p1 = 0.053; p2 = 0.164), respectively. CONCLUSION: Preoperative measurement of macular hole size with OCT can provide a prognostic factor for postoperative visual outcome and anatomical success rate of macular hole surgery. The duration of symptoms did not correlate with the diameters measured. Base and minimum diameters especially seem to be of predictive value in macular hole surgery.

Aged↗
PubMed2001

Indocyanine green selectively stains the internal limiting membrane.

PURPOSE: To demonstrate whether indocyanine green stains the inner limiting membrane of the retina or residual vitreous cortex. METHODS: We report on the intraoperative staining patterns of the vitreomacular interface in 10 eyes of 10 consecutive patients who underwent vitrectomy with indocyanine green staining for macular hole formation and diffuse diabetic macular edema. RESULTS: In five eyes of five patients with macular holes, indocyanine green staining of the macula after posterior vitreous detachment resulted in an immediate visibility of a discernable membrane that was not previously seen. In five eyes of five patients with diffuse diabetic macular edema and adherent cortical vitreous, indocyanine green failed to stain the vitreomacular interface. After peeling off the residual vitreous cortex, however, a discernable membrane could be identified using indocyanine green dye again. Light and transmission electron microscopy revealed the inner limiting membrane as the membrane that had been stained and removed in all specimens. CONCLUSION: Indocyanine green selectively stains the inner limiting membrane. Staining of the vitreomacular interface using indocyanine green as a vital dye enables the surgeon to distinguish between the residual vitreous cortex and the inner limiting membrane, and it allows safer and easier removal of the inner limiting membrane.

Basement Membrane↗
PubMed2001

Indocyanine green-assisted peeling of the internal limiting membrane may cause retinal damage.

PURPOSE: To demonstrate possible retinal damage caused by indocyanine green dye for staining of the internal limiting membrane in surgery for idiopathic macular hole. METHODS: Consecutive interventional case series. We report on the ultrastructural findings of the internal limiting membrane in 10 eyes of 10 patients. RESULTS: All specimens revealed not only the internal limiting membrane, but also some small amounts of retinal elements, such as the plasma membrane of Müller cells and other undetermined structures. This indicates a cleavage plane not exactly at the inner undulating aspect of the internal limiting membrane but within the innermost retinal layers. CONCLUSION: Dilutions of indocyanine green as recommended in the literature may alter the structure of the retina to some degree. Possible factors responsible for this inadvertent action may include (1) concentration, (2) osmolarity pH, (3) time of tissue contact, and (4) mechanical factors from more forceful traction during peeling. Although functional consequences of these findings remain unclear as yet, factors that may induce damage to the innermost retina should be elucidated.

Basement Membrane↗
PubMed2001

Central retinal artery occlusion in association with an aneurysm of the internal carotid artery.

PURPOSE: To report an unusual case of central retinal artery occlusion in a 41-year-old woman. DESIGN: Interventional case report. METHODS: A 41-year-old woman presented with sudden and painless decrease of visual acuity of the left eye. Indirect ophthalmoscopy revealed the typical fundus findings of a central retinal artery occlusion. The fovea was spared by a cilioretinal arteriole. RESULTS: Cerebral angiography showed an aneurysm of the left internal carotid artery, measuring approximately 1.7 x 1.5 x 1.7 cm. The aneurysm was located in close proximity to the ophthalmic branch. CONCLUSION: Aneurysm of the intracranial arteries should be included in the differential diagnosis of central retinal artery occlusion in young patients.

Adult↗
PubMed2001

[Diagnosis and differential diagnosis of the combined hamartoma of the retina and retinal pigment epithelium].

BACKGROUND: The combined hamartoma of the retina and the retinal pigment epithelium (CHR-RPE) is an important differential diagnosis of retinal and choroidal diseases with variable degrees of pigmentation. PATIENTS: The clinical picture and typical fluorescence angiography findings of two adult patients who were first diagnosed to have a combined hamartoma of the retina and retinal pigment epithelium are presented. The referral diagnosis macular pucker and malignant melanoma of the choroid, respectively, are discussed regarding severe therapeutic interventions such as pars plana vitrectomy with membrane peeling (macular pucker), and radiotherapy, or enucleation (malignant melanoma of the choroid) as well as other important differentials. RESULTS: The combined hamartoma of the retina and the retinal pigment epithelium is a benign congenital, mostly unilateral retinal lesion. The presenting symptom is a painless, unilateral, often silent loss of vision. Histologically, three cell populations can be identified: glial, vascular, and pigmented cells. Variations in composition of these three cell types are responsible for the heterogeneous clinical picture and thus diagnostic challenges. The greyish retinal tumor located peripapillary in most cases with varying degrees of pigmentation and surrounding vascular tortuosity can result in secondary changes at the vitreoretinal interface with deterioration of vision. Combined fluorescein-/indocyaningreen angiography and ultrasound are crucial for diagnostic evaluation. Documentation and regular clinical follow-up examinations are essential for successful management of this disorder. CONCLUSION: Recognition of this rare clinical entity is crucial for administering the appropriate therapy.

Adult↗
PubMed2001

Central corneal thickness measurement with a retinal optical coherence tomography device versus standard ultrasonic pachymetry.

PURPOSE: To demonstrate the capability of a standard, commercially available optical coherence tomography device (originally designed to measure retinal thickness) to image the human cornea in vivo and to measure central corneal thickness (CCT) in normal and edematous corneas. The intrapatient precision and interpatient variability of this novel application was compared to standard ultrasonic pachymetry. Also, the correlation of both methods was investigated. METHODS: CCT measurements using optical coherence tomography (OCT) and ultrasonic pachymetry (PACH) were obtained in 36 normal eyes and 16 eyes with corneal edema. RESULTS: Direct in vivo imaging of the cornea and measurements of CCT by OCT could be performed in all eyes. In normal subjects, CCT(OCT) was 530+/-32 microm and CCT(PACH) was 581+/-34 microm. The two methods showed a highly significant correlation with a standardized regression coefficient of 0.988. The difference between both methods was constant over the range of CCT (mean difference, 49.4+/-5.9 microm). The mean intrapatient SD of CCT measurements was 4.90 microm and 4.96 microm for OCT and PACH, respectively. In patients with corneal edema, mean CCT(OCT) was 601+/-59 microm, and mean CCT(PACH) was 667+/-68 microm. The difference between the two techniques increased slightly with increasing corneal edema (mean difference, 66.9+/-10.9 microm). CONCLUSION: Imaging of the human cornea can be performed by a standard retinal OCT device, and OCT measurement of CCT shows excellent correlation to values obtained by PACH, giving similar readings separated by a constant difference. In corneal edema, the difference between the two methods is additionally increased, but continues to demonstrate excellent consistency.

Adult↗
PubMed2001

Comparison of foveal thickness measured with the retinal thickness analyzer and optical coherence tomography.

PURPOSE: To assess and compare the reliability and reproducibility of retinal thickness measurements for the retinal thickness analyzer (RTA) and optical coherence tomography (OCT) in normal and edematous retina. METHODS: The authors measured the foveal thickness of 21 normal eyes and 9 eyes with macular edema with both methods in random order. With the RTA, the fovea was measured 10 times; with the OCT, six scans (one horizontal and five vertical cross-sections) of the fovea were obtained. RESULTS: Mean foveal thickness of normal eyes measured 153 microm with OCT and 181 microm with RTA (median for both methods 150 microm). Coefficients of variation (CV) within the same subjects were 10% (OCT) and 9% (RTA) reducing to 9% (OCT) and 7% (RTA) when scans were repeated only five times for both methods. The RTA, however, yielded an interpatient CV of 33% (OCT 17%), which was caused by several falsely high readings in normal individuals. In eyes with retinal thickening the OCT measured a mean of 324 microm with 15% intra- and 58% interpatient CV. The RTA yielded a mean of 403 microm with CV of 18% and 73%, respectively. CONCLUSION: Both methods yield reproducible measurements of foveal thickness in normal individuals and individuals with macular edema. However, falsely high measurements may occur with the RTA, reducing its reliability as compared to the OCT.

Anthropometry↗
PubMed2000

[Imaging of vitreoretinal adhesions in the partner eye of patients with penetrating macular foramina in optical coherence tomography].

BACKGROUND: Vitreoretinal adhesions play a crucial role in the development of a macular hole. To visualize vitreoretinal adhesion we used optical coherence tomography to investigate fellow eyes of patients with macular holes. METHODS: In a prospective study we scanned the retina in 188 patients with a macular hole stage III or IV (Gass classification). The foveal shape and vitreous were classified into grades. RESULTS: Of the 188 patients 45% showed no vitreous reflex, 45% a partial vitreous detachment with foveolar adhesions, and 10% a vitreous detachment with complete separation from the fovea. While eyes with normal foveolar shape displayed partial vitreous detachment in 33%, this figure rose to 66% in eyes with a macular hole stage I. CONCLUSION: Diffuse thickening of the fovea is followed by an intraretinal split and formation of a cyst. The shape of the foveolar adhesion suggests that continuing anteroposterior vitreal traction leads to a retinal break and formation of a full-thickness macular hole.

Aged↗
PubMed2000

[Multifactorial analysis of therapeutic outcome of pseudophakic retinal detachment surgery].

BACKGROUND: Pseudophakic retinal detachment is one of the most severe complications after cataract surgery and is a common cause of permanently reduced visual acuity. We evaluated parameters predicting reduced functional outcome by a model of stepwise regression analysis. PATIENTS AND METHODS: A series of 102 consecutive patients with pseudophakic retinal detachment were analyzed for various parameters regarding cataract surgery, retinal surgery, and retinal detachment features. First, univariate analysis determined the correlations with reduced functional outcome. Secondly, a stepwise regression model analyzed statistically significant variables for their predictive value of a reduced visual outcome. RESULTS: The overall reattachment rate was 99%. In 69% of the patients there was an improvement of more than two lines at the end of the follow-up period. The most predictive factors for reduced functional outcome were the need for a silicone oil tamponade and the visual acuity prior to retinal detachment surgery. When silicone oil tamponade was not needed, the requirement of more than two retinal surgeries was the most predictive factor for reduced visual outcome. CONCLUSION: In our series the strongest predictive factors for a reduced functional outcome were the necessity of silicone oil, reduced visual acuity at the time of retinal detachment, and the requirement of more than two retinal surgeries. These findings suggest that first-line procedures should not be necessarily minimally invasive measurements but rather procedures that result in a stably attached retina in the first instance without permanent silicone oil tamponade, even if this first operation consists of an extended pars plana vitrectomy.

Adult↗