Biomedical subjects

J P Hoops

Publications and source records attributed to J P Hoops.

8 recordsLinked to original sources

PubMed2004

Retinal vascular abnormalities in CADASIL.

To assess retinal vascular alterations in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, the authors examined 10 affected individuals with ophthalmologic evaluation including fluorescence angiography. Findings included bilateral peripapillary arteriolar sheathing (30%), arteriolar narrowing (80%), and arteriovenous nicking (90%). No retinal infarcts, vascular occlusions, exudation, or hypoperfusion of affected vessels were found.

Adult↗

PubMed2001

[3-D ultrasound. Initial experiences in various eye diseases].

BACKGROUND: Studies have confirmed three-dimensional (3-D) ultrasound as a practical diagnostic tool in examining the eye and orbit and suggest its routine clinical use. MATERIALS AND METHODS: 3-D ultrasound was prospectively performed in 46 patients (46 eyes) with various ocular diseases. In six large choroidal melanomas the tumor volume were measured by 3-D ultrasound and compared to that measured by MRI and to that calculated by a theoretical formula. To assess the reproducibility of volumetry by 3-D ultrasound the volumes of such three intraocular tumors were measured ten times using ten different virtual sectioning planes and a section thickness of 0.5 mm and/or 1.0 mm. RESULTS: 3-D ultrasound allows the precise assessment of complex three-dimensional structures. Choroidal melanoma volumes measured by 3-D ultrasound, MRI, and theoretical calculation were in the same range. CONCLUSION: Intraocular tumor volume can be measured well by 3-D ultrasound,which may be of clinical importance in follow-up examinations.

Choroid Neoplasms↗

PubMed2001

Preoperative evaluation of limbal dermoids using high-resolution biomicroscopy.

BACKGROUND: Only a few case reports have described the ultrasound biomicroscopic features of limbal dermoids. It remains unclear whether examination by ultrasound biomicroscopy (UBM) can detect the corneal depth of penetration which would improve planning of surgery. METHODS: Eight consecutive patients [two female, six male, 1-24 years old (median 8.5 years)] examined by UBM (Zeiss-Humphrey, 50 MHz) were retrospectively studied. Five of the dermoids were excised without corneal grafting and histopathological evaluation was obtained. RESULTS: Seven out of eight dermoids were located in the temporal lower quadrant. A Goldenhar syndrome was known in three cases. In all cases but one, UBM showed a more reflective and predominantly homogeneous lesion compared with the unaffected corneal stroma, so that the lateral margins of the lesion could be clearly identified. Incomplete stromal penetration of the dermoid was noticed in four cases; one eye showed a corneal full thickness dermoid. An intraocular protrusion was seen in one eye. Two more cases remained unclear because of reduced compliance. Descemet's membrane beneath the dermoid could not be visualized in most cases (seven out of eight) because of strong sound attenuation inside the lesion. Histopathological evaluation of five cases revealed the typical signs of a limbal dermoid. CONCLUSION: UBM improves the preoperative evaluation of limbal dermoids. Subtle examination technique for the depth of corneal penetration is required because of the strong sound attenuation in this tissue, reducing the visibility of deep corneal structures.

Adolescent↗

PubMed2000

[Stereotaxic precision irradiation of large uveal melanomas with the gamma knife].

BACKGROUND: We report our experience with stereotactic radiosurgery using the Gamma-knife in large uveal melanoma unsuitable for brachytherapy (Ru106). PATIENTS AND METHODS: We treated 35 patients (16 male, 19 female; age: median 59 years (95% Confidence interval (CI): 31-84 years; 18 right eyes, 17 left eyes). 7 tumors were located juxtapapillary, 16 tumors were located in the mid-periphery and 12 tumors were located in the ciliary body, The localization and/or the dimension of the tumors did not allow for radiation brachytherapy (Ru106). All patients underwent regular clinical, echographical and neuroradiological follow-up examinations. RESULTS: The follow-up time was median 12 months (95% CI: 4-20 months). A local tumor control defined as either continuous tumor regression or stopping of tumor progression was achieved in 34 (97%) of the 35 treated patients within the observation period. The eye of one patient was enucleated due to tumor regrowth. Maximum apical tumor height according to standardized A-scan before treatment was median 9.1 mm (95% CI: 3.2-13.9 mm) and after treatment median 6.4 mm (95% CI: 2.1 bis 11.9 mm). The difference was statistically highly significant (p < 0.001, one-tailed paired t-test). CONCLUSIONS: Our results in 35 patients indicate that radiosurgery using the Gamma-knife is beneficial in retaining the eyes of patients with large uveal melanomas that are not suitable for brachytherapy (Ru106).

Adult↗

PubMed2000

[Bilateral retinal microangiopathy in interferon therapy of malignant melanoma of the skin].

BACKGROUND: Interferon associated retinopathy has been described mainly by Japanese working groups as a complication of systemic interferon therapy for various diseases. In Europe, only few reports exist, especially regarding interferon therapy for dermal malignant melanoma. PATIENT: We report a 58-year-old female patient with symptomatic, bilateral microangiopathy caused by interferon for metastatic dermal malignant melanoma. Multiple bilateral cotton wool spots caused visual field defects and unilateral decreased visual acuity. The retinal changes were reversible when stopping interferon therapy. CONCLUSION: Interferon-associated microangiopathy occurs as a complication of interferon therapy independently of the treated systemic disease. Rarely, retinopathy becomes symptomatic as reported in this case. Symptoms were fully, clinical signs were partially reversible. A regular ophthalmologic monitoring of all patients receiving interferon therapy is recommended. Monitoring aims to detecting vision-threatening retinal changes in a reversible phase.

Female↗

PubMed1999

In vivo imaging of the human zonular apparatus with high-resolution ultrasound biomicroscopy.

BACKGROUND: To investigate the potential of high-resolution ultrasound biomicroscopy (UBM) for studying the zonular apparatus of human beings in vivo. METHODS: Using transducer frequencies of 34 MHz and 50 MHz, criteria were developed to identify transcorneal and transscleral sections that allowed reproducible identification of the different fiber groups of the zonular architecture. For that purpose, 10 volunteers between the ages of 14 and 41 years underwent high-resolution ultrasound biomicroscopy under conditions of consensual far- and near-accommodation. The online video recordings of the respective UBM investigations were afterwards analyzed image by image. Good visibility of zonular fibers was obtained when the ultrasound wave propagation comprised an angle close to 90 degrees with the fiber orientation and when the oscillations of the UBM scan had a strict radial orientation towards the limbus and avoided, simultaneously, the ciliary processes. RESULTS: In all the volunteers, high-resolution ultrasound biomicroscopy imaged the zonular fiber groups known from histology. In addition, it detected fibers that do not follow the course of the inner ciliary body surface but take a direct route from the ora serrata to the lens. It also demonstrated that fibers that seem to change direction at crossings with other fibers. Under conditions of near-accommodation, the zonular fibers showed signs of relaxation. CONCLUSIONS: High-resolution ultrasound biomicroscopy seems well suited for in vivo investigations of the zonular apparatus and of accommodation in man. The results support the fundamental features of the Helmholtz theory on accommodation.

Accommodation, Ocular↗

PubMed1998

[Choroid neovascularization in age-related macular degeneration. Correlation of histological and fluorescence angiography findings].

BACKGROUND: Recent studies have raised confusion about the fluorescein angiographical and histopathological correlation of CNV. MATERIAL AND METHODS: The preoperative fluorescein angiograms of four patients with subfoveal CNV due to ARMD extracted by pars plana vitrectomy were classified as wellor ill-defined CNV and were correlated to the histopathologically (in serial sections) verrified CNV-location (subneuroretinal (= type II according to Gass) versus sub-RPE (type I according to Gass)). RESULTS: The locations of all four CNV could be classified by histopathological landmarks as there were RPE, BLD/drusen, and inner Bruchs membrane. Angiographically welldefined membranes were type II membranes according to Gass, whereas the ill-defined membrane represented type I. The CNV with well- and ill-defined borders consisted of type II and type I parts according to Gass. CONCLUSION: We find subneuroretinal locations of the well-defined CNV examined (type II membranes according to Gass). Correspondingly, ill-defined CNV or ill-defined parts of a CNV seem to be beneath the RPE (type I). The correlation of fluorescein angiography and histopathology should be studied in greater numbers of well- and ill-defined CNV.

Bruch Membrane↗

PubMed1997

[Dural carotid-cavernous sinus fistulas: clinical aspects, diagnosis and therapeutic intervention].

BACKGROUND: Carotid cavernous fistulas are cerebral artenovenous shunts which may present with ocular or orbital signs. Direct fistulas are distinguished from dural shunts with respect to the anatomical situation. PATIENTS: We report on two patients with spontaneous dural carotid cavernous fistulas with multiple feeding vessels. Both patients required endovascular embolization. RESULTS: Therapy was successful in both patients. We present an overview of the clinical picture, the diagnostic procedure, the differential diagnosis and the therapeutic possibilities in this clinical entity. CONCLUSION: Both patients prove the importance of an immediate differential diagnostical classification so that a specific neuroradiological diagnostic can be ensured. Today's advanced endovascular technology offers therapeutic options with less risk for the patient than in recent years.

Arteriovenous Fistula↗