Biomedical subjects

F H Stefani

Publications and source records attributed to F H Stefani.

At least 37 records · Page 2Linked to original sources

PubMed1992

Detection of small RB1 gene deletions in retinoblastoma by multiplex PCR and high-resolution gel electrophoresis.

Loss of function of both copies of the RB1 gene is a causal event in the development of retinoblastoma. The predisposition to this tumor can be inherited as an autosomal dominant trait. Direct detection of the genetic defect is important for presymptomatic DNA diagnosis and genetic counseling in families with hereditary retinoblastoma. We have used multiplex polymerase chain reaction and high-resolution polyacrylamide gel electrophoresis to detect RB1 gene deletions as small as one base pair. By using three independent sets of amplification reactions, which cover 26% of the RB1 gene coding region, we identified RB1 gene deletions in the DNA of peripheral blood cells in 3 out of 24 (12.5%) unrelated patients with hereditary retinoblastoma. In one case, formalin-fixed paraffin-embedded tumor material was also used to detect the mutation. Sequencing of the mutated alleles revealed deletions of 1, 3 and 10 base pairs. Each deleted region was flanked by direct repeats.

Amino Acid Sequence↗

PubMed1992

Contractile cells in the human scleral spur.

The scleral spur in 37 human (age 17-87 years) and six cynomolgus monkey eyes (2-4 years) was investigated. Serial meridional and tangential sections were studied with ultrastructural and immunocytochemical methods. The bundles of the ciliary muscle do not enter the scleral spur, but their tendons, which consist of elastic fibres join the elastic fibres in the scleral spur. Within the scleral spur a population of circularly oriented and spindle-shaped cells is found. In contrast to the ciliary muscle cells, the scleral spur cells form no bundles, but are loosely aggregated. They have long cytoplasmic processes and are connected to each other by adherens-type and gap junctions. They stain intensely for alpha-smooth muscle actin, myosin and vimentin. In contrast to the ciliary muscle cells, they do not stain for desmin. Ultrastructurally, the scleral spur cells contain abundant thin (actin) filaments, but do not otherwise show the typical ultrastructural features of ciliary muscle cells. The scleral spur cells do not express a complete basal lamina. They form individual tendinous connections with the elastic fibres in the scleral spur, which are continuous with the elastic fibres of the trabecular meshwork. The scleral spur cells are in close contact with nerve terminals containing small agranular (30-60 nm) and large granular (65-110 nm) vesicles but also with terminals containing small granular (30-60 nm) vesicles which are regarded as typical for adrenergic terminals. We conclude that the scleral spur cells are contractile myofibroblasts. Their contraction might influence the rate of the aqueous outflow.

Adolescent↗

PubMed1992

Progressive loss of cytochrome c oxidase in the human extraocular muscles in ageing--a cytochemical-immunohistochemical study.

Cytochrome c oxidase (complex IV of the respiratory chain) was studied histochemically in autoptic human extraocular muscles (n = 135), revealing randomly distributed single fibers without enzyme activity. The enzyme defect was expressed in all the mitochondria of an involved fiber as evidenced by ultracytochemistry. Succinate dehydrogenase showed normal histochemical reactivity. The defects occurred already in the second decade and were regularly seen from the third decade on. The defect density (defects/mm2) increased from approx. 1/mm2 below the fifth decade to about 4/mm2 in advanced age (P = 0.000). The highest defect density was observed in the levator palpebrae muscle. On the whole, the defect density was about 5-6 times higher in the extraocular muscles than in the limb muscle, diaphragm and heart (Müller-Höcker, 1989, 1990). Immunocytochemical detection of cytochrome c oxidase showed that loss of cytochrome c oxidase activity was due to an almost complete absence of both nuclear and mitochondria subunits of the enzyme. The results document different organ and heterogenic cellular sensitivity to the age-related loss of cytochrome c oxidase. The loss of both mitochondrial and nuclear subunits indicates that nuclear factors are most probably involved in the decline of the respiratory chain function in senescence.

Adolescent↗

PubMed1992

Pyogenic granulomas of the lacrimal sac.

Eight cases of pyogenic granulomas of the lacrimal sac are reported. The clinical symptoms were consistent with chronic dacryocystitis which was unresponsive to previous probing and antibiotics. Extirpation of the sacs was done because of dacryocystocoele, pyocoele, or fistula formation through the skin. Trauma and inflammation were thought to have contributed to the growth of the pyogenic granulomas. The histopathological examination revealed nonspecific granulomas consisting of well vascularised, friable tissue of a myxomatous nature containing an infiltration of lymphocytes, plasma cells, and a few eosinophils. Over the granulomas an epithelial layer of cells is stretched showing no signs of dysplasia or neoplastic growth. The term 'lobular capillary hemangioma' has been suggested to describe lesions morphologically similar to those observed in the study. These masses made up 53.3% of a total of 15 lacrimal sac tumour biopsy specimens examined over a period of 10 years (1979-1989). The few reported cases of primary lacrimal sac tumour of non-epithelial origin suggest that they make up a large minority of the lacrimal sac tumours. A review shows that relatively few of these lesions have been described in recent English literature but these growths are probably not being as consistently reported as primary epithelial tumours.

Adult↗

PubMed1992

Immunoimaging of choroidal melanoma: assessment of its diagnostic accuracy and limitations in 101 cases.

Immunoscintigraphy (IS) was performed on 101 patients with space occupying intraocular lesions including choroidal melanomas (85), choroidal naevi (11), non-melanoma metastases (three), and other melanoma simulating lesions (two). Scintigraphic images with conventional and emission computer tomography techniques were obtained after the intravenous injection of 99mTc-labelled F(ab')2 fragments of monoclonal antibody (MoAb) 225.28S directed against the high molecular weight-melanoma associated antigen (HMW-MAA). Immunohistochemistry was performed on sections of four out of 10 melanoma-containing eyes to confirm MoAb binding. IS demonstrated positive scans in 66 out of 85 choroidal melanomas, offering a sensitivity of 78%. Sensitivity was dependent on the lesion size. True negative results were obtained in 15 out of 16 non-melanoma lesions (specificity 94%). False positive antibody accumulation was found in one patient with a post-traumatic subretinal haemorrhage. Immunohistochemistry demonstrated positive MoAb 225.28S binding in all melanoma sections. In summary IS offered substantial sensitivity and specificity in the differentiation of intraocular lesions, particularly choroidal melanomas, naevi, and metastases. In combination with other diagnostic procedures such as ultrasound echography and fluorescein angiography IS proved to be a valuable method in the diagnosis of choroidal melanoma.

Choroid↗

PubMed1992

Spindleform scleropathy: collagen changes of the sclera. A pathologic report.

To our knowledge, this is the first pathologic report of interscleral collagen bundle changes occurring as well-defined spindleform lesions randomly interspersed within the sclera. The lesions were observed in an otherwise healthy 75-year-old man whose eye was enucleated because of a uveal malignant melanoma. There are few reports in the literature of focal scleral changes of a predominantly acid mucopolysaccharide nature. The entity we observed in this case differs from these reports by its spindleform appearance, random distribution (not overlying the melanoma) and predominantly vicinal glycol nature. Histopathologic, histochemical, and ultrastructural studies revealed that the lesions were not the result of mucoid degeneration of the scleral collagen and not an abnormal collagen structure.

Aged↗

PubMed1992

Quantitative color Doppler imaging in untreated and irradiated choroidal melanoma.

Histological data indicate the importance of tumor vascularization as a determinant of the biological behavior and the response to radiotherapy in choroidal melanoma. Duplex ultrasound and color Doppler imaging, the combination of B-mode ultrasound and pulse-waved Doppler analysis, were used to measure quantitatively neovascular blood flow in 31 patients with choroidal melanoma. Follow-up studies (20 patients) were performed to investigate the change of tumor blood flow in choroidal melanomas after radiotherapy. Blood flow was detected in 30 out of 31 melanomas (size 3.1-17.8 mm) within the tumor and at the tumor base with a mean peak systolic frequency of 1.0 kHz (range 0.3-2.7 kHz), a mean end diastolic frequency of 0.3 kHz (range 0.1-1.0 kHz), and a mean frequency of 0.7 kHz (range 0.2-1.3 kHz). Two and six months after 106Ru/106Rh beta-ray application, 19 patients showed a significant decrease in peak systolic frequency. This occurred with and in advance of the decrease in the tumor size. In one patient, a rising maximum systolic frequency after radiotherapy marked a recurrent tumor growth. Results indicate that the quantitative measurement of tumor blood flow by duplex ultrasound and color Doppler imaging may be a new diagnostic modality for monitoring the effectiveness of radiotherapy in choroidal melanoma.

Adult↗

PubMed1991

Unilateral diplophthalmos.

In a child born of a full-term pregnancy, unilateral diplophthalmos without proboscis was observed along with other craniocervical abnormalities (ipsilateral temporoparietal porencephaly, supernumerary teeth, and cervical cyst). A globe almost normal in shape and size was observed within the left orbit. The upper quadrant of this globe was attached to a smaller, pear-shaped, supernumerary eye containing a small lens, normal vitreous humor, ciliary body structures, avascular retina, choroid, and a rudimentary optic disk. When a two-peaked and enlarging intraocular mass was observed clinically, the eye was enucleated because of suspected neoplasm. The enlarging prominence had been caused by the growing second globe. Our findings indicated that a single primary optic vesicle was formed (globe I with an optic fasciculus), and some unknown damage was caused when this single primary optic vesicle induced the lens formation by contacting the ectoderm. Although the conception and early embryonal life of this child had taken place during a period of increased radiation exposure caused by the explosion of the nuclear plant at Chernobyl, U.S.S.R., in the spring of 1986, it seemed unlikely that the abnormality could have been caused by radioactive fallout in the mountains of Austria.

Abnormalities, Multiple↗

PubMed1991

Second nonocular tumors in cured unilateral retinoblastoma patients.

According to recent data the incidence of second tumors in cured hereditary unilateral retinoblastoma patients is 20% within 10 years, 50% after 20 years and rises to 90% after 30 years. Nonhereditary unilateral retinoblastoma patients have not been regarded as susceptible for second nonocular tumors so far. A case is reported of such a patient having developed a second presacral retroperitoneal tumor after successful treatment of a nonhereditary unilateral retinoblastoma group V without intracranial extension or pulmonary metastases. Consequently all (hereditary and non-hereditary) retinoblastoma patients should receive at least quarterly intensive follow-up examinations after primary ophthalmologic treatment.

Child, Preschool↗

PubMed1991

Medulloepithelioma of the ciliary body.

Neuroepithelial tumors of the ciliary body occur more seldom than retinoblastoma. The congenital form is called medulloepithelioma, the adult-acquired adenoma or adenocarcinoma. Medulloepitheliomas consist of organoid epithelial structures developing anteriorly along surfaces such as the iris. The authors report on a congenital type unusually growing not only anteriorly along the lens, but also posteriorly along the retina's surface causing retinal detachment.

Child↗

PubMed1990

Epithelial tumors of the lacrimal gland: clinico-pathologic correlation and management.

Between 1960 and 1987 29 patients underwent surgery at the Munich University Eye Hospital for benign and malignant tumors of the lacrimal gland. Fifteen tumors were classified as pleomorphic adenomas (three of them with malignant transformation), nine as adenoid cystic carcinomas, two as adenocarcinomas, two as oxyphilic adenomas, and one as oxyphilic adenocarcinoma. The clinico-pathologic correlation of these tumors is described. All age groups were involved in both benign and malignant epithelial gland tumors. A fast growing lesion with bone destruction of the lacrimal fossa in association with pain was found to be highly suspicious of a malignant epithelial tumor. Prior to surgery, inflammatory lesions and lymphomas should be ruled out by clinical history, examination, diagnostic imaging techniques, and, occasionally, by a short course of oral corticosteroids. A diagnostic biopsy prior to tumor excision and a transfrontal surgical approach via craniotomy has a negative impact on the prognosis. Thus it is mandatory to remove epithelial lacrimal gland tumors completely at the time of the initial surgical procedure. Craniotomies facilitate recurrences of lacrimal gland tumors by infiltration into the central nervous system. Lateral orbitotomies using the Krönlein technique are the best surgical approach for successful removal of these unusual tumors.

Adenocarcinoma↗

PubMed1990

[Histopathology of the retina, optic fascicle and lateral geniculate body in chronic, bilateral symmetric ischemic Schnabel's cavernous optic atrophy].

The paper is a unique pathological description of a bilateral, symmetric, anterior, temporal ischemic optic neuropathy with the morphological characteristics of cavernous optic atrophy initially described by Schnabel in glaucomatous eyes. The 80-year-old woman had suffered from cardiac insufficiency and diabetes mellitus for many years. She died from sepsis and circulatory collapse due to ischemic colitis, intestinal perforation, and peritonitis. There was widespread arteriosclerosis but no evidence of giant-cell arteritis. Cell loss was demonstrated in both retinas, the chiasm, and in the central lateral geniculate body. These represent a retrograde, descending and ascending optic atrophy, with transsynaptic degeneration in the LGB. A small craniopharyngioma was found by chance in the infundibulum. Neither clinically nor morphologically were there any signs of glaucoma.

Aged↗

PubMed1990

[Unilateral iritis by cysticercal larva in the anterior chamber].

An 8-year-old girl complained of progressive pain, visual loss and photophobia in her right eye for 1 week. Treatment with local steroids for acute iritis had not been successful. Slitlamp examination revealed a marked cellular and fibrinous inflammatory reaction of the anterior chamber and a whitish, fibrin-like structure on the surface of the iris. There was mild serum eosinophilia and leucocytosis. The suspected organic material was removed surgically. By light and electron microscopy, parts of the wall of a helminthic parasite were discovered, anatomically consistent with the diagnosis of an immature stage of Taenia solium found in cysticercosis. Such cases of intra-ocular parasitosis are described very rarely but might still occur, although there is no history of suspicious typical exposition to parasites. It is important to know that eosinophilia may be insignificant or even absent and that complete surgical removal will be the only successful treatment.

Animals↗

PubMed1990

Intraocular in vivo immunofluorescence. A new technique for visualizing structures of the ocular fundus.

A new noninvasive technique for observing structures in the living eye has been developed: the technique is based on intravenous application of specific antibodies, labeled with fluorescein. The immunologically marked substructures of the fundus of the eye, the only transparent organ in mammals, are photographed directly using high speed film. Combined with a digital image processor to enhance low contrast contours, this technique can be used for diagnostic purposes, as shown in rabbits with experimental toxoplasmic chorioretinitis.

Animals↗

PubMed1990

[Early ocular symptoms in Wegener's granulomatosis].

Wegener's granulomatosis is characterized by necrotizing granulomatous vasculitis that initially occurs in a localized form, disseminates in various degrees and particularly involves the respiratory tract and kidneys. Eye manifestations are common (40 to 60%). Both clinical and histopathological findings are described in eight patients with Wegener's granulomatosis. The initial ocular symptoms included conjunctivitis, episcleritis, scleritis, corneoscleral ulceration, uveitis and ocular proptosis. In one patient histological examination of the orbital tissue was consistent with limited Wegener's granulomatosis 6 years before generalized granulomatous vasculitis confirmed the underlying disease. As new diagnostic and therapeutic modalities (detection of antineutrophil cytoplasmatic autoantibodies and therapy with trimethoprim-sulfamethoxazole) exist, a knowledge of the ocular initial symptoms of Wegener's granulomatosis can have considerable significance.

Adult↗

PubMed1990

[Oculoplastic therapy in generalized nevus verrucosus].

The clinical and histopathological picture of a 27-year-old patient with generalized nevus verrucosus is described. The oculoplastic treatment performed in this patient consisted in lid plasties, surgical excision, cauterization and cryotherapy. The different therapeutic techniques were applied over a period of 2 years. Nearly all papillomatous lesions were removed without impairing lid contour or lid function.

Adult↗

PubMed1989

[Tumor markers in malignant choroid melanoma].

Antibodies against tumor-associated antigens ("tumor markers") can be used for the diagnosis of malignant tumors. Eight different monoclonal antibodies, that can recognize tumor-associated antigens of dermal melanomas, were tested in cryostat sections of uveal melanomas. The uveal melanomas showed antigenic differences (e.g., gangliosides) and common antigens (e.g. high molecular weight melanoma-associated antigen) in comparison to dermal melanomas. The implications of these results for diagnosing and even treating uveal melanomas are discussed.

Alkaline Phosphatase↗

PubMed1989

[Radiation cataract following injection of radium 224].

The Spiess Ra-224 series ist presented. It consists of 900 patients who were repeatedly injected intravenously with known dosages (microCi/kg) of the alpha-particle emitter Ra-224 for the intended treatment of tuberculosis and ankylosing spondylitis between 1943 and 1952/1965. 682 patients had been treated as adults after the age of 20 years, and 218 hat been injected as "juveniles" aged 20 years or younger. All 218 "juvenile" patients except one who had suffered from ankylosing spondylitis, had been injected for tuberculosis. Among the 218 patients 91 have died leaving 127 alive. Of the "juvenile" patients 9 were examined at the Eye Hospital of the Universität München including histopathology of an autopsy eye in one case. Of the 9 patients 8 proved to have some cataracts and 2 appeared morphologically similar to age-related cataract. In 6 patients there was a posterior subcapsular cataract which was a dense round plaque with a clear subcapsular zone of about 0.5 to 0.6 mm. This clear zone corresponds well to newly deposited lens fibres during the period of about 40 years from treatment to examination.

Adolescent↗