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R Rochels

Publications and source records attributed to R Rochels.

At least 19 recordsLinked to original sources
PubMed2001

[The efferent lacrimal ducts of the human. Morphological and biochemical studies].

PURPOSE: Infections occur frequently in the region of the efferent tear ducts. Exact knowledge of the anatomical structure and of cellular defense mechanisms is necessary to understand the pathological processes. This study analyzed the efferent tear ducts with regard to physiological function and possible defense mechanism against infections. MATERIALS AND METHODS: We used histological, immunohistochemical and electronmicroscopic techniques to investigate the lacrimal systems from 31 body donors aged 54-88 years. RESULTS: The efferent tear ducts are lined by a double-layered epithelium resting on a broad basement membrane. These cells contain many lipid droplets and secretory vacuoles in their apical part. Inside the epithelium cells are arranged partly in cell groups forming mucous glands, which morphologically resemble goblet cells of the tarsus palpebrae. The secretory products of these cells contain various carbohydrates including sialic acid. Lymphocytes and macrophages are found in the submucosa partly penetrating the epithelium. CONCLUSIONS: Lipids and mucins of epithelial and goblet cells form a specialized protective layer on the epithelium of the tear ducts which enables easy drainage of tear fluid into the inferior meatus of the nose. Together with immunocompetent cells the protective layer prevents invasion of pathogenetic agents.

Aged↗
PubMed2001

Current concepts in the classification, diagnosis and treatment of hemangiomas and vascular malformations of the head and neck.

There are many different classifications of vascular anomalies. As the correct classification of the vascular lesion has a direct influence on therapy it is difficult to decide which treatment should be considered as the treatment of choice. Based on an extensive review of the literature and personal experience of the treatment of more than 200 patients with hemangiomas or vascular malformations of the head and neck, a clinical classification is described that allows vascular lesions to be categorized in order to plan purposeful treatment. In general, hemangiomas represent the main group of vascular lesions in infancy and childhood. They are usually apparent a few weeks after birth and are characterized by an initially rapid growth of epithelial cells, followed by spontaneous involution. Hemangiomas should be differentiated from vascular malformations that are present at birth but may not be evident clinically. Spontaneous involution of vascular malformations has never been reported, whereas laser therapy can induce involution of hemangiomas at an early stage in a majority of cases. In certain situations steroids or surgical removal may seem to be the appropriate therapy of choice. In contrast, vascular malformations have to be treated according to their histopathology and location, as well as their hemodynamic features as shown radiographically with angiography. The accurate diagnosis of vascular anomalies is essential for further treatment, as shown by clinical experience at the University of Marburg.

Arteriovenous Malformations↗
PubMed2000

Molecular genetics of Meesmann's corneal dystrophy: ancestral and novel mutations in keratin 12 (K12) and complete sequence of the human KRT12 gene.

Recently, we identified the first mutations in corneal keratins K3 and K12 in families with Meesmann's corneal dystrophy (MCD). Here, we sequenced all regions of the human K12 gene, to enable mutation detection for all exons using genomic DNA as a template. The human K12 genomic sequence spans 5919 bp and consists of eight exons. A microsatellite dinucleotide repeat was identified within intron 3, which was highly polymorphic and which we developed for use in genotype analysis. In addition, two mutations in the helix initiation motif of K12 were found in families with MCD. A novel mutation was detected in an American kindred, 410T-->C, which predicts the amino acid substitution M129T. In a German family, mutation 428G-->C was identified, predicting amino acid change R135T. The latter mutation was identical to that which we identified in the original kindred described by Meesmann. Using the intragenic microsatellite polymorphism in K12 and additional flanking markers, we were able to show that this family shares a common haplotype with the original Meesmann kindred. These results strongly imply that R135T represents an ancestral mutation in the German population. Both mutations occur in the highly conserved helix initiation motif of the K12 polypeptide. A total of eight mutations have now been reported in the K12 gene.

Corneal Dystrophies, Hereditary↗
PubMed2000

[Mutations in the keratin gene as a cause of Meesman-Wilke corneal dystrophy and autosomal dominant skin cornification disorders].

BACKGROUND: Meesmann's corneal dystrophy (OMIM 122,100) is a rare autosomal dominant disorder of the corneal epithelium. It manifests in early childhood and affects both eyes. The disease is characterized by variable patterned dot-like corneal opacities and intraepithelial vesicles, which can be seen by slit-lamp examination and retro-illumination. Further signs include punctate erosions, lacrimation, photophobia, and blepharospasm. Vision is usually only slightly diminished. By histology, the corneal epithelium is irregularly thickened. It shows vacuolated epithelial cells and intraepithelial formation of vesicles. By electron microscopy fibrogranular aggregates are seen in the cytoplasm of epithelial cells. RESULTS: Linkage analyses in descendants of the family described by Meesmann and Wilke and other affected kinships showed that the putative genetic defect locates within the keratin type I gene cluster on chromosome 17 (17q12-21). Molecular genetic analyses in more than ten affected families showed that mutations in the cornea-specific keratin genes K3 and K12 represent the causative genetic defects of the disease phenotype. CONCLUSION: Comparative studies in autosomal dominant skin disorders of cornification suggest that the mutations identified in patients with Meesmann's corneal dystrophy exert dominant negative effects on keratin filament assembly. Disturbed filament formation results in intracellular keratin clumping, identifiable as fibrogranular aggregates. As a result the mechanical resilience of the affected cells and the epithelial tissue appears markedly reduced. Whether abnormalities of functionally related structural proteins, e.g. desmosomal components, could result in a phenotype similar to Meesmann and Wilke's corneal dystrophy remains to be seen.

Child↗
PubMed2000

[Differential diagnosis of sinugenic enophthalmos].

BACKGROUND: Spontaneous enophthalmos without recent trauma is a rare condition. Its origin is difficult to evaluate. METHOD: Specific properties of this symptom complex are presented based on a literature review and on case reports. Possible connections between enophthalmos and paranasal sinus diseases as well as differential diagnoses are analysed. PATIENTS: 1. 31 year old female patient with right spontaneous enophthalmos and no history of trauma. CT-imaging disclosed tissue formation in the maxillary sinus, partially destroyed medial orbital wall and floor, descended orbital contents following Caldwell-Luc procedure several years previously. After endonasal surgery of ethmoidal and maxillary sinus with removal of a large cyst good functional and cosmetical result. 2. 25 year old male patient complaining of pain in the periorbital region, presenting with left enophthalmos and superonasal deviation of the eyeball. MRI and CT revealed a tumor in the orbital floor region with total destruction of the roof of the maxillary sinus. Removal of the tumor by a combined lateral rhinotomy and subciliary approach. DIAGNOSIS: Leiomyoma. Orbital reconstruction with PDS-sheet. Postoperatively, improved globe position and motility. No recurrence during three year follow-up. CONCLUSION: When evaluating the causes of enophthalmos, chronic diseases of the paranasal sinuses or their walls must be considered. Surgical therapy is promising.

Adult↗
PubMed2000

A novel keratin 12 mutation in a German kindred with Meesmann's corneal dystrophy.

AIM: To study a kindred with Meesmann's corneal dystrophy (MCD) to determine if a mutation within the cornea specific K3 or K12 genes is responsible for the disease phenotype. METHODS: Slit lamp examination of the cornea in four members of the kindred was carried out to confirm the diagnosis of MCD. The region encoding the helix initiation motif (HIM) of the K12 polypeptide was polymerase chain reaction (PCR) amplified from genomic DNA derived from affected individuals in the kindred. PCR products generated were subjected to direct automated sequencing. Restriction enzyme analysis employing Ban I was used to confirm the presence of the mutation in affected individuals of the family. RESULTS: Sequencing of the K12 gene in an affected individual from the family revealed a novel heterozygous missense mutation (413A-->C), predicting the substitution of a proline for a glutamine at codon 130 (Q130P) in the HIM of the K12 protein. The mutation was excluded from 50 normal, unaffected individuals by restriction enyzme analysis and was therefore unlikely to be a common polymorphism. CONCLUSION: A novel missense mutation in the K12 gene leads to MCD in a German kindred. Missense mutations have now been identified within the region encoding the helix initiation motif of the K12 protein in eight of 11 MCD kindreds analysed at the molecular level.

Corneal Dystrophies, Hereditary↗
PubMed1999

Primary orbital leiomyoma and leiomyosarcoma.

A case of an extremely rare primary orbital leiomyoma in a 25-year-old male patient is presented who had a lifelong history of deviation of the left eye globe with slight enophthalmos and reduced motility. Because of pain and increasing deviation of the eye the tumor was totally resected. On histologic examination the tumor showed ossification which is extremely rare so that a calcifying fibroma had to be ruled out. In immunohistochemistry, however, this tumor stained with smooth muscle antigen. Less than 2% of cells stained positive for Ki-S1, a proliferation marker. The second case is a rare primary orbital leiomyosarcoma in an 84-year-old female patient that showed massive growth. After exenteration histologic examination showed a dedifferentiated highly malignant soft tissue tumor which expressed desmin and smooth muscle actin but was negative for myoglobin, S-100 and HMB-45.

Adult↗
PubMed1998

Functional anatomy of the human efferent tear ducts: a new theory of tear outflow mechanism.

BACKGROUND: The mechanism of lacrimal drainage under physiological conditions is controversial. The aim of this study was to analyze the three-dimensional architecture of human efferent tear ducts from functional and clinical points of view. A new theory of tear outflow is discussed. METHODS: Thirty-two prepared lacrimal systems of adults were examined by histological, immunohistochemical and scanning electron microscopic techniques. RESULTS: The wall of the lacrimal sac is made up of collagen bundles, elastic and reticular fibers arranged in a helical pattern. Wide luminal vascular plexus are embedded in this helical system and connected to the cavernous tissue of the inferior turbinate in the region of Hasner's valve. Immunohistochemical analysis showed evidence of type I and type III collagen as well as chondroitin 4- and 6-sulfate. CONCLUSION: With blinking, the lacrimal part of the orbicularis muscle contracts. The fornix of the sac moves in a cranial-lateral direction. Thus the lacrimal sac distends and may be "wrung out" due to its medial attachment and helically arranged fibrillar structures. The vascular plexus may play an important role in the absorption and drainage of lacrimal fluid.

Aged↗
PubMed1998

Functional anatomy of human lacrimal duct epithelium.

Resorption of tear fluid in the lacrimal ducts has hitherto been controversial; one reason for this has been insufficient knowledge of the anatomical structure and function of the lacrimal duct epithelium. The present study analyzes the structure of lacrimal duct epithelium by means of histological, histochemical, immunohistochemical and electronmicroscopical methods and draws a conclusion about its physiological function regarding its role in immunodeficiency. Investigations were performed on 31 lacrimal systems of 17 male and 14 female individuals (aged 54-88 years). Lacrimal ducts are surrounded by a wide-ranging cavernous system, which is embedded in an osseous canal between the maxilla and the lacrimal bone. The internal wall of the lacrimal canaliculi is lined by a stratified epithelium. The lacrimal sac and nasolacrimal duct contain a double-layered epithelium, which rests on a broad basement membrane. In their apical part epithelial cells contain large lipid droplets and secretory vacuoles. Epithelial cells are faced by microvilli and some tufts of kinociliae are also visible. Goblet cells are integrated in the epithelium as solitary cells or in a characteristic arrangement of several cells. The secretory product of these cells contains carbohydrates including fucose and sialic acid. Inside the surrounding cavernous system serous glands are found that open their excretory ducts into the lacrimal sac and nasolacrimal duct. Some T- and B-lymphocytes and macrophages may be demonstrated immunohistochemically in the submucosa partly penetrating the epithelium. Synthesized mucins of goblet cells form a specialized protective layer on the epithelium of the lacrimal ducts, which functionally serves for a simplified drainage of tear fluid into the inferior meatus of the nose. Together with immunocompetent cells, the protective layer plays a role in antigen defense and prevents invasion of pathogenic agents. The facing of epithelial cells by microvilli gives hints of re-absorption of lacrimal fluid inside the lacrimal ducts.

Aged↗
PubMed1997

Primary antiphospholipid antibody syndrome and retinal occlusive vasculopathy.

PURPOSE: To report a 31-year-old healthy patient with retinal venous occlusion in his left eye attributable to primary antiphospholipid antibody syndrome. METHODS: The patient was examined clinically. Multiple serologic and clinical investigations were performed to determine the causative disease. He was closely followed up for more than 3 years. RESULTS: The presence of lupus anticoagulant in our patient was indicated by a kaolin clotting time index of 27 (normal, <17) and confirmed by the demonstration of IgG antibodies against phospholipids. After long-term oral anticoagulant treatment for 2 years, lupus anticoagulant levels returned to normal, and therapy was stopped. No further thrombotic event occurred during follow-up. CONCLUSIONS: In retinal vascular occlusions of unexplained origin, antiphospholipid antibodies may play an important role in the pathogenesis. Detecting these antibodies in the serum of patients with retinal vascular occlusion helps determine the appropriate treatment with long-term oral anticoagulants.

Adult↗
PubMed1997

Mutations in cornea-specific keratin K3 or K12 genes cause Meesmann's corneal dystrophy.

The intermediate filament cytoskeleton of corneal epithelial cells is composed of cornea-specific keratins K3 and K12 (refs 1,2). Meesmann's corneal dystrophy (MCD) is an autosomal dominant disorder causing fragility of the anterior corneal epithelium, where K3 and K12 are specifically expressed. We postulated that dominant-negative mutations in these keratins might be the cause of MCD. K3 was mapped to the type-II keratin gene cluster on 12q; and K12 to the type-I keratin cluster on 17q using radiation hybrids. We obtained linkage to the K12 locus in Meesmann's original German kindred (Zmax = 7.53; theta = 0) and we also showed that the phenotype segregated with either the K12 or the K3 locus in two Northern Irish pedigrees. Heterozygous missense mutations in K3 (E509K) and in K12 (V143L; R135T) completely co-segregated with MCD in the families and were not found in 100 normal unrelated chromosomes. All mutations occur in the highly conserved keratin helix boundary motifs, where dominant mutations in other keratins have been found to severely compromise cytoskeletal function, leading to keratinocyte fragility phenotypes. Our results demonstrate for the first time the molecular basis of Meesmann's corneal dystrophy.

Cornea↗
PubMed1997

[ORBIT-NET. Discussion forum on orbitology on the internet].

INTRODUCTION: A basic service in the public network "Internet" is electronic mail (e-mail). E-mail makes the participation in discussion groups possible by mailing contributions to the discussion to all members electronically. To complement the existing list of ophthalmologic discussion groups ORBIT-NET was introduced. It offers experts in research, clinic, diagnostic and therapy of orbital diseases the opportunity to make queries or present interesting casuistries and to ask for comments, differential diagnosis or advice on therapy. Other participants can be made aware of new scientific results, actual publications or meetings. MATERIAL AND METHODS: For participation a computer, a modem, an Internet-Provider and special software are required. Registration is made either by e-mail or regular mail. A verification is necessary to limit the list of participants to experts. RESULTS: Since the introduction of ORBIT-NET on November 9th, 1996, there have been no technical problems. ORBIT-NET has been effective as a platform. CONCLUSIONS: The international, interdisciplinary platform ORBIT-NET is an addition to the existing ophthalmologic discussion groups. ORBIT-NET offers orbitologists an international discussion of results and diagnosis, supports further training and can give encouragement to further research.

Computer Communication Networks↗
PubMed1996

[Changes in extracellular matrix in the lamina cribosa of patients with secondary glaucoma].

The aim of this study was to analyze the localization and distribution of extracellular matrix in normal and glaucomatous damaged optic discs using immunohistochemical methods. Five eyes donated for corneal allografting without any history of glaucoma and three other eyes with secondary glaucoma were studied. Immunohistochemical reactions were performed with antibodies against collagen types I, III, IV and VI and against laminin, proliferating antigen KI67 and GFAP. In glaucomatous eyes the characteristic arrangement of collagen fibrils is lacking. Septa of the lamina cribrosa appear enlarged. The immunoreactivity of all examined collagen types is stronger in glaucomatous eyes. The axon basement membranes show an irregular and interrupted pattern. The number of proliferating cells with positive GFAP staining in glaucomatous cribriform plates is distinctly higher. We postulate that fibroblasts and astrocytes in the stroma of glaucomatous lamina cribrosa could be stimulated to increased and uncontrolled proliferation. Associated disorganization and raised secretion of extracellular matrix may lead to axon constriction and, secondarily, to neural degeneration.

Adult↗
PubMed1996

[Orbital hematomas].

BACKGROUND: Orbital hematomas may occur spontaneously, as a result of vascular anomalities, or they may be induced by trauma or occur following paranasal sinus surgery. The retrobulbar hematoma requires special attention because of its potential compression of the optic nerve may compromise vision or cause blindness. PATIENTS AND METHODS: We report on four cases: two subperiostal orbital hematomas, a spontaneous retrobulbar hematoma, and one orbital hematoma due to trauma. RESULTS: In one case a vascular anomality was detected by angiography. Though temporary blindness occurred in this case, it was possible to preserve 30% vision by surgery. An infected subperiostal hematoma was successfully treated using an endonasal approach. Two cases (a traumatic and a subperiostal orbital hematoma) required no operative treatment. CONCLUSIONS: The diagnosis of an orbital hematoma should be made as quickly as possible to permit adequate early therapy. Decrease of vision or blindness caused by orbital hematoma may be improved through a lateral canthotomy as emergency measure and subsequently by draining the hematoma to relieve compression of the optic nerve.

Adult↗
PubMed1996

Scanning electron-microscopic studies of the collagen architecture of the human sclera--normal and pathological findings.

The arrangement of the collagen fibrils of the human sclera was analyzed in the region of the limbus cornea, the corneoscleral trabeculum, at the zone of muscle insertion and at defined areas of the internal and external surface of the sclera. Adult eyes with no apparent pathological alterations and the sclera of a patient with staphyloma were examined by scanning electron microscopy. The investigations were performed to describe regularities in the collagen architecture in normal and pathologically altered eyes to understand pathomorphologic and pathophysiologic changes in scleral diseases.

Aged↗