Biomedical subjects

A Hassenstein

Publications and source records attributed to A Hassenstein.

11 recordsLinked to original sources

PubMed2005

[OCT in epiretinal gliosis].

Biomorphometric studies using optical coherence tomography (OCT) in patients with epiretinal membranes reveal a highly reflective membrane, a significant foveal thickening, loss of the foveal depression, and the presence of intraretinal cysts. Epiretinal membranes are more frequently totally adherent than separated with focal points of adherence. Visual acuity correlates with foveal thickness prior to and 6 months after vitrectomy and surgical removal of epiretinal membranes. Foveal thickening regresses postoperatively, but normal values are seldom reached. Marked foveal thickening, nonexistent foveal depression, and extensive cyst formation are supposed to correlate with a rather poor visual outcome. OCT plays a pivotal role in the differential diagnosis of pseudomacular hole in epiretinal membranes and of full-thickness macular hole. In addition to biomicroscopy and fluorescein angiography, OCT images provide valuable information for a structural assessment of the macula, especially in evaluating the postoperative course of macular surgery.

Epiretinal Membrane↗

PubMed2004

[Optical coherence tomography in optic pit and associated maculopathy].

BACKGROUND: Of patients with an optic pit 30% develop an associated maculopathy of unknown origin. We report on 8 patients with an optic pit and associated maculopathy evaluated by optical coherence tomography (OCT) for detection of structural retinal changes and indications for the pathogenesis. PATIENTS AND METHODS: A total of 8 patients (mean age 25 years) suffering from an optic pit and associated maculopathy were evaluated by biomicroscopy, fluorescein angiography (FLA) and OCT and the results were compared. RESULTS: Visual acuity was on average 0.5 (0.05-0.8). Funduscopy revealed a macular elevation. In clinically suspected 'pseudo' macular hole, OCT revealed foveal schisis. OCT demonstrated a retinal detachment with a typical convex schisis of the outer retinal layer (n=6), and three patients showed a neurosensory detachment with (n=2) and without (n=1) intraretinal cystoid formation. CONCLUSION: The typical macular schisis pattern in OCT in optic pit with serous maculopathy helps to differentiate this condition from other macular elevations.

Adolescent↗

PubMed2004

[OCT in macular holes].

The traditional Gass classification of macular holes can now be supplemented by additional and more detailed morphologic information obtained with optical coherence tomography (OCT). The perifoveal vitreous detachment and subsequent anterior foveal traction is considered to be the primary pathomechanism of macular hole formation. In cases of persistent traction on the fovea it may lead to foveal dehiscence. A possible explanation for intraretinal cyst formation may be secondary vitreous body fluid accumulation within the retina. A classification of macular holes based on additional information from OCT images is possible. Thus, OCT is a valuable tool for differential diagnosis of a pseudo macular hole versus macular hole, precise stage classification, therapy decision making process, outcome control after macular surgery, and prognosis prediction.

Diagnosis, Differential↗

PubMed2003

[Testing central retinal function with multifocal electroretinography before and after photodynamic therapy].

BACKGROUND: Photodynamic therapy (PDT) is applied for certain forms of choroidal neovascular membrane (CNV). The aim of this study was to investigate the effect of PDT on central retinal function as assessed by multifocal electroretinography (ERG). METHODS: 24 patients (25 eyes) with CNV (>50% classic 12 eyes) or occult (9 eyes) in age related macular degeneration (AMD) and CNV with pathological myopia (4 eyes) were treated by PDT using Verteporfin((R)). Before and a median of 6 weeks after therapy, central retinal function was examined using multifocal ERG (RetiScan, 61 hexagons, first-order response). RESULTS: In the area of treatment,we found a tendency of the amplitude of the first positive deflection (P1) to decrease and of the implicit time to increase, but both effects were not statistically significant. These alterations were more pronounced in eyes with occult CNV and in myopia-related CNV. Amplitude reduction and implicit time prolongation could also be found in the areas represented by the multifocal ERG but not treated. There was no significant correlation between change in visual acuity after PDT and amplitude of the multifocal ERG. CONCLUSION: The effects of PDT on retinal function seem to be moderate as assessed by multifocal ERG. An inherent problem of this investigation was the recruitment of nontreated patients as controls. Future goals are investigations of patients with repeated PDT and of long-term alterations in multifocal ERG after PDT.

Adult↗

PubMed2001

[Subretinal granuloma, retinal vasculitis and keratouveitis with secondary open-angle glaucoma in schistosomiasis].

BACKGROUND: More than 250 million people in Africa and Asia currently suffer from schistosomiasis, however, ocular manifestations of this disease are rare in Germany. PATIENT AND FOLLOW-UP: We present the case of a 32-year-old patient from Gambia who had been resident in Germany for 3 years and suffered from a painful persistent diarrhoea, fever and a reduction of visual acuity (R > L). On admission, the patient reported a schistosomiasis in 1994, which was diagnosed by a skin test and was not adequately treated because of the side-effects of praziquantel. Vision was OD-0.75 sph 0.8, OS sc 1.0, IOD OD 31, OS 18 mmHg. Biomicroscopy: R > L fatty retrocorneal precipitates, especially in the lower circumference (ARLT), large inflammatory cells and Tyndall ++, vitreous with large inflammatory cells, Fundus: OD at 11 o'clock large subretinal granuloma in the periphery. Serum lysozyme was elevated (22.2 mg/l, normal range 10-17 mg/l), a syphilis stage II-III (TPHA 1:5000, VDRL neg.) and an IgG-antibody titre for Schistosoma mansoni of > 30 micrograms/ml was detected by enzyme immunoassay. In the faeces and urine no schistosoma eggs were found. Before the specific treatment for schistosomiasis could be initiated, the patient left the hospital because of reduced ocular pain due to the corticosteroids and fear of the side-effects of the treatment. DISCUSSION: In patients who present a subretinal granuloma and report a painful persistent diarrhoea, schistosomiasis, which is one of the most frequent tropical diseases should be considered, even if they have been living in central Europe for several years. Although the disease cannot become established due to the lack of specific hosts in this area, a curative treatment should be enforced in order to prevent late manifestations of chronic inflammatory organ manifestations.

Adult↗

PubMed2001

[Optical coherence tomography in geographic atrophy--a clinicopathologic correlation].

BACKGROUND: Optical coherence tomography was used for the examination of patients with geographic atrophy in different stages of age-related macular degeneration. Always compared with biomicroscopy and fluorescein angiography [4,7,8,10]. PATIENTS AND METHODS: 37 patients with geographic atrophy (n = 55 eyes) out of 150 with AMD (n = 169 eyes) were examined. The results of biomicroscopy, fluorescein angiography, optical coherence tomography and histological knowledge in age-related macular degeneration were studied. RESULTS: Fluorescein angiography always identified geographic atrophy and in 13.5% the findings additionally were similar to an occult choroidal neovascularisation with circular hyperpigmentation. Geographic atrophy shows a significant thinning of the neurosensory retina of 135 microns as an average in optical coherence tomography (p < 0.0005) which did not correlate to visual acuity. Typically an enhanced vertically sharp demarcated reflectivity of the choroid is found because of the lacking pigment epithelium. 43% of the geographic atrophies were identified by optical coherence tomography. 3 out of 55 eyes (5%) in optical coherence tomography only show macular holes additionally to geographic atrophy. CONCLUSION: A typical pattern of reflectivity is found by optical coherence tomography with enhanced reflectivity of the choroid because of lacking pigment epithelium and significant thinning of the fovea. Atypical macular holes moreover are found in 5% neither appearing in biomicroscopy nor in fluorescein angiography. An occult choroidal neovascularisation can be differentiated by optical coherence tomography from geographic atrophy because there is no spindle-like thickening of the pigment epithelium and no enhanced choroidal reflectivity. In borderline cases optical coherence tomography may be helpful and therapeutically decisive in differentiating geographic atrophy and occult choroidal neovascularisation and in detecting atypical macular holes.

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↗

PubMed1999

[r-tPA in keratoplasty à chaud. Report of 50 patients].

BACKGROUND: Fibrinolytic treatment using recombinant plasminogen activator (r-tPA) has been reported in cataract surgery; however, reports are lacking with respect to complex surgical interventions including keratoplasty because of anterior segment infections. PATIENTS AND METHODS: This report deals with a prospective study comprising 50 patients (50 eyes) suffering from a serpent ulcer treated by keratoplasty à chaud. r-tPA (25 micrograms) was instilled intracamerally at the end of surgery in 25 eyes. RESULTS: The 25 eyes treated with r-tPA were subsequently less inflamed than the control population (decrease in inflammatory cells 1.5 days vs 7 days, fibrin reaction 1x vs 12x), had highly significantly better visual acuity and there was significantly reduced inpatient hospitalization (median 9.9 vs 19.3 days). No hemorrhages were observed in either population; medically treated infection recurrences (S. aureus, C. tropicalis, acanthameba) were observed in 3 and primary graft failure or rejection in both populations 3x. CONCLUSIONS: This study showed that perioperative application of r-tPA had a beneficial effect. This therapeutic avenue should be further evaluated in a randomized, double-masked multicenter study.

Adolescent↗

PubMed1999

Tapioca melanomas of the iris: immunohistology and report on two cases.

BACKGROUND: Tapioca-like tumors are rare, and their benign or malignant nature is obscure without histological work-up. We report on the clinical and histological features of different types of tumors in two patients. CASE REPORT: Two patients aged 17 and 45 years presented with brownish iris masses increasing in size. Full-thickness en bloc excision of melanocytic tumors (5.5 mm and 7.0 mm in diameter) was carried out. Histological work-up revealed a nevus cell nevus in the young patient and an epithelioid malignant melanoma in the middle-aged patient evolving from the ciliary body. Staining for HMB-45 was marked in both tumors, for S-100 low in the nevus and marked in the melanoma, and for p53 negative in the nevus and positive in the melanoma. Ki67 stains were negative. CONCLUSION: We propose that excision of anteriorly located pigmented tumors that increase in size is indicated in order to determine whether they are benign or malignant. In these case reports, tapioca-like tumors include a benign and a malignant entity. To our knowledge, a nevus cell nevus presenting as a tapioca-like tumor has not previously been described. Curative surgery and histological and immunohistological evaluation are required to characterize the malignant potential of these tumors and the prognosis.

Adolescent↗

PubMed1998

[Intraocular pseudotumor in an AIDS patient. Block excision, differential diagnosis, histology].

BACKGROUND: Intraocular pseudotumors are a rare event in Aids patients and often pose diagnostic problems. CASE REPORT: A 37-year-old patient who had had HIV seroconversion for 7 years was seen to developed progressively growing, multiple, disseminated, subretinal lesions OD > OS, accompanied by exudative retinal detachment and iritis. Since all etiological laboratory diagnostic efforts to detect an infectious, noninfectious and neoplastic systemic lesion failed, a diagnostic and curative therapeutic chorioretinal excisional biopsy specimen of the largest of the tumors (3 x 3 x 2 mm) was taken. The histological work-up demonstrated granulation tissue similar to an intraocular pseudotumor without signs of infection, malignancy or reactive lymphoid hyperplasia. This finding resulted in systemic corticosteroid treatment with complete resolution of the lesions in both eyes and no recurrences. CONCLUSIONS: An invasive diagnostic procedure in patients suffering from lesions of unknown cause resulting in the institution of an appropriate medical treatment may be beneficial for the integrity and vision of the respective eye.

Adult↗

PubMed1998

Limitations of imaging choroidal tumors in vivo by optical coherence tomography.

BACKGROUND: Optical coherence tomography (OCT) produces two-dimensional cross-sectional images with a longitudinal resolution of 10 microns. Its capacity for imaging retinal structure has been shown in a variety of diseases. There are no reports on its capacity and limitations in imaging choriocapillary and choroidal structures. METHODS: Twenty-two patients with the diagnosis of malignant melanoma of the choroid were submitted to OCT. We used a prototype and a commercial device, both with an 850-nm superluminescent diode with a band-width of 30 nm (reported longitudinal resolution 10 microns). The images were evaluated for retinal thickness, changes in retinal pigment epithelium, subretinal fluid accumulation and changes in choriocapillary or choroidal reflectivity. RESULTS: Retinal edema and detachment found on biomicroscopic examination for fluorescein angiography was detected by OCT in all such cases. In 2 of 22 cases small retinal detachments were detected only by OCT. Tumor extension through the retinal pigment epithelium was not seen in this series, either by biomicroscopy or by OCT. The pattern of choroidal or choriocapillary reflectivity was nonspecifically lower than that of normal choroid, but did not yield any additional information about tumor histology. When normal retina was present, the OCT appearance of a malignant melanoma resembled that of normal choroid. CONCLUSION: OCT may provide information about the retinal structure overlying prominent tumors and the extent of adjacent retinal detachment. In its present state of development, OCT is of little value in the differential diagnosis of choroidal tumors. Its potential value for the follow-up of shallow tumors needs further investigation.

Adult↗