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Biomedical subjects

R L Font

Publications and source records attributed to R L Font.

At least 163 records · Page 9Linked to original sources
PubMed1982

'Cholesteatoma' of the orbit.

'Cholesteatoma' of the orbit is a variant of pseudotumor histologically characterized by masses of cholesterol crystals. We propose the term "epidermoid or true cholesteatoma" for lesions containing epithelial elements and refer to those nonepithelium-containing pseudotumors as "cholesterol granulomas." Important clinical features distinguish between epidermoid cholesteatomas and cholesterol granulomas of the orbit and justify a separation of these two pathologic entities.

Adolescent↗
PubMed1982

Iris nodules in von Recklinghausen's Neurofibromatosis. Electron microscopic confirmation of their melanocytic origin.

A 75-year-old man had generalized neurofibromatosis (NFT) with bilateral iris nodules and a mature cataract with elevated intraocular pressure in his left eye. At the time of intracapsular cataract extraction, a sector iridectomy was performed. Electron microscopic studies of the iris nodules within the iridectomy specimen unequivocally established that the spindle-shaped cells within the nodules were of melanocytic origin. We believe that the iris nodules in NFT represent melanocytic hamartomas.

Aged↗
PubMed1982

Hemangioendothelioma of frontal bone.

Radiographic studies disclosed that a 5-year-old girl with proptosis and inferior displacement of her left globe had a lytic lesion in the superior orbital rim. Tissue removed at the time of the initial biopsy was not sufficiently distinctive for a definitive diagnosis, but microscopic examination of residual tumor clearly established the diagnosis of hemangioendothelioma of the frontal bone. Electron microscopic studies demonstrated that the vascular structures, which resembled endothelium, contained many thin microfilaments and mitochondria and scattered dense bodies. Each vessel was surrounded by a prominent mantle of pericytes.

Child, Preschool↗
PubMed1982

Carcinoid tumors of the eye and orbit: a clinicopathologic study of 15 cases, with histochemical and electron microscopic observations.

This clinicopathologic study includes 15 cases of carcinoid tumors of the eye and orbit. The patients ranged in age from 14 to 86 years (median, 53). No prediction for either gender was found. Seven tumors involved the orbit, seven the choroid, and one the iris. The primary site of origin of the carcinoid tumor was known in 12 cases: seven in the bronchus, one in the trachea, and four in the ileum. In three cases an orbital tumor was present but no other known primary neoplasm was clinically apparent. The postoperative follow-up period ranged from 0 to 4 years. The urinary levels of 5-hydroxyindoleacetic acid (5-HIAA) were elevated in four of ten patients tested, each of whom had a known primary tumor and two of whom had clinical evidence of the carcinoid syndrome. Four main histologic patterns were recognized: pattern A (solid lobules or masses), pattern B (trabecular or cord-like), pattern C (tubular or rosette-like) and pattern D (mixed). The apparently primary carcinoid tumors and the orbital or ocular metastases were closely related by their histologic patterns, histochemical staining characteristics, and ultrastructural features.

Adolescent↗
PubMed1982

Hemangioblastomas: histogenesis of the stromal cell studied by immunocytochemistry.

Twenty-one cases of hemangioblastoma from the cerebellum, spinal cord and retina were studied using the unlabeled antibody peroxidase-antiperoxidase technique with antibodies directed against glial fibrillary acidic protein (GFAP) and factor VIII related antigen (VIIIR:Ag). In 19 of 21 cases studied with anti-GFAP, astrocytes were identified peripherally, and in 13 cases they were found centrally within the tumor. In no instance did stromal cells react positively for GFAP. Sixteen cases with anti-VIIIR:Ag antibody were examined, and in all cases many stromal cells showed positive staining. It is concluded that the stromal cells were of endothelial origin. The occasional stromal cells that other investigators have identified as reacting positively for GFAP may represent stromal cells capable of ingesting extracellular GFAP derived from reactive astrocytes within the tumor, or they may be lipidized astrocytes.

Antigens↗
PubMed1982

Fibrous histiocytoma of the orbit. A clinicopathologic study of 150 cases.

This is a clinicopathologic study of 150 cases of fibrous histiocytoma of the orbit. The tumors occurred in adults (median age, 43 years). The upper and nasal portions of the orbit were the most common sites of involvement. The most common signs and symptoms were proptosis (60 per cent), mass (46 per cent), and decreased vision (25 per cent). Based on the histopathologic features, the tumors were classified in three groups: benign (94 cases), locally aggressive (39 cases), and malignant (17 cases). The biological behavior correlated well with the duration of symptoms, the size and margins of the mass, and the histologic classification. The rate of recurrence was 31 per cent for the benign tumors, 57 per cent for the locally aggressive tumors, and 64 per cent for the malignant tumors. Follow-up data were obtained for 123 patients, with a mean duration of seven years. The ten-year survival of patients with benign, locally aggressive, and malignant fibrous histiocytoma was 100 per cent, 92 per cent, and 23 per cent, respectively. Nine patients died as a result of the tumor, six from local invasion of adjacent structures and three from metastatic disease. Fibrous histiocytoma is the most common primary mesenchymal orbital tumor of adults. The origin of the neoplasm is probably a primitive mesenchymal cell. Complete surgical excision appears to be the treatment of choice.

Adolescent↗
PubMed1982

Hemangiopericytoma of the orbit: a clinicopathologic study of 30 cases.

The clinical and pathologic features of 30 orbital hemangiopericytomas were reviewed. An effort was made to determine the clincopathologic characteristics that may correlate with the biologic behavior. Histopathologic criteria evaluated included degree of cellularity, nuclear atypia, mitotic activity, tumor size, and the presence of hemorrhage and necrosis. Histopathologically, 16 tumors were classified as benign, five as borderline, and nine as malignant. Follow-up information was obtained in 27 cases (mean duration of follow-up period was five and one-half years). Eight tumors recurred (30 per cent). Five patients died, four with widespread metastases (15 per cent) and one of unrelated causes. Tumors that recurred or metastasized were distributed among all three histologic groups. The interval between the onset of symptoms and metastasis for three of the four lethal tumors was 31 years, 28 years, and 8 1/2 years; in the fourth case it was unknown. For the entire series, the five-year actuarial survival rate was 89 per cent. Although the number of cases is too small to serve as a basis for firm conclusions, the lack of unequivocal correlation between the histologic features and clinical behavior is consistent with the unpredictable behavior of this neoplasm, as concluded by other investigators. Because of the apparent circumscription of most of these tumors, complete surgical excision rather than exenteration is recommended. Metastasis usually develops late in the clinical course of the disease, indicating that long-term follow-up studies are required before a cure can be assumed.

Adolescent↗
PubMed1982

Adenoid cystic carcinoma of the lacrimal gland: the clinical significance of a basaloid histologic pattern.

The authors reviewed 74 adenoid cystic carcinomas of the lacrimal gland, 54 of which had sufficient follow-up data for analysis of survival. Patients with a basaloid pattern in their tumor had a five-year survival rate of 21 per cent and a median survival of three years, whereas patients whose tumor contained no trace of a basaloid component had a five-year survival rate of 71 per cent and a median survival rate of eight years. Nonparametric statistical analysis revealed that this difference in survival was significant at the 0.0005 level. The authors propose that, in the future, pathologists label all adenoid cystic carcinomas as either "basaloid" or "nonbasaloid" and code each case accordingly.

Adult↗
PubMed1982

Alveolar soft-part sarcoma of the orbit: a clinicopathologic analysis of seventeen cases and a review of the literature.

This is a clinicopathologic study of 17 cases of alveolar soft-part sarcoma of the orbit. The mean age of patients was 23 and the median was 18 (range, 11 months to 69 years); 13 patients (76.5 per cent) were women and four were men (ratio, 3.25:1). The right and left orbits were equally involved (eight patients each), and in one the laterality was not specified. Histologically, the tumors had a distinctive organoid pattern outlined by thin-walled capillaries and were composed of nests of large polyhedral cells with abundant, finely granular, acidophilic cytoplasm. Approximately two thirds of the tumors had diagnostic PAS-positive diastase-resistant crystalline structures. Histologically, the differential diagnosis included nonchromaffin paraganglioma, granular cell tumor, metastatic renal cell carcinoma, vascular tumor, alveolar rhabdomyosarcoma, and amelanotic malignant melanoma. Electron microscopic studies of one tumor disclosed mitochondria with abnormal cristae, increased amounts of glycogen, and cytoplasmic crystalline structures with a periodicity of 8 to 10 nm. Smaller membrane-bound electron-dense granules appeared to be precursors of the crystals. Follow-up studies showed that eight patients were alive and well (median follow-up period, 11.4 years). Six of the eight patients at the time of diagnosis were 20 years of age or younger. A ninth patient was alive and well 13 years after excision of the orbital mass and four years after bilateral thoracotomy with resection of nine pulmonary nodules. Two patients died as a result of metastatic disease, one 14 years and the other 21 years after initial orbital surgery. Two patients died of other causes, one of whom had pulmonary metastases at autopsy. The follow-up period on two recent cases was less than three years, and two patients were lost to follow-up. The disease pursued an indolent clinical course. Surgery offers the best chance to control the disease.

Adolescent↗
PubMed1981

Silica granuloma of eyelid and ocular adnexa.

Seven cases of subcutaneous epithelioid granulomas caused by silica and involving the eyelids and periorbital region are described. Histologically, all cases disclosed epithelioid tubercles and varying numbers of foreign-body-type giant cells, areas of scarring, and birefringent crystals. Light microscopy with polarized readily facilitated visualization of the crystals. Scanning electron microscopy and energy dispersive x-ray analysis clearly established that the crystals were composed of silica in both its pure and combined forms. This study emphasizes the need for examination of all epithelioid granulomas with polarized light. If crystalline foreign bodies are identified, further special techniques should be used for chemical characterization of the crystals.

Adult↗
PubMed1981

Nosematosis of the cornea. Case report, including electron microscopic studies.

A 26-year-old woman underwent enucleation of a blind, painful eye because of a perforated corneal ulcer. Histopathologic examination of the eye disclosed an acute, necrotizing keratitis surrounding myriad small (2.5 to 3 x 4.5 to 5 micrometer), oval, faintly visible structures. Under polarized light, they were partially birefringent and stained intensely positive with the acid-fast technique. The organisms were located mainly within the cytoplasm of histiocytes in the deep corneal lamellae. They were interpreted as a protozoa of the genus Nosema. The diagnosis was confirmed by electron microscopic studies. The distinguishing features between Nosema species and Encephalitozoon are discussed. To our knowledge, this is the second documented case of corneal nosematosis.

Adult↗
PubMed1980

Juvenile fibromatosis of the periorbital region and eyelid. A clinicopathologic study of six cases.

Six cases of juvenile fibromatosis of the periorbital region and eyelid were studied. The median age of the patients was 8 years (range, 1 to 11 years). A definite propensity for involvement of the infraorbital region and lower eyelid was observed. THREE TUMORS EXHIBITED A PROMINENT LOBULAR PATTERN AND WERE ADHERENT TO THE PERIOSTEUM. The main entities in the differential diagnosis included leiomyoma, neurofibroma, and well-differentiated fibrosarcoma. Two of six tumors recurred locally but did not metastasize. Electron microscopic studies disclosed that the spindle-shaped tumor cells exhibited features of fibroblasts. It appears that conservative treatment (ie, local excision) is adequate.

Child↗
PubMed1980

Nonglaucomatous cavernous degeneration of the optic nerve. Report of two cases.

The globes from two elderly women who underwent enucleation for malignant melanoma of the choroid showed cavernous degeneration of the optic nerve. Both individuals had prominent optic cups and a strong family history of severe cardiovascular disease; one patient also had mild anemia and substantial arteriosclerotic heart disease. Neither patient showed any clinical or histologic evidence of glaucoma. It is proposed that cavernous degeneration of the optic nerves in some patients may represent an aging change associated with generalized arteriosclerosis. Individuals with large optic cups may be more at risk of developing this condition.

Aged↗
PubMed1980

Plasmacytic conjunctivitis with crystalline inclusions. Immunohistochemical and ultrastructural studies.

A 17-year-old girl had bilateral papillary conjunctivitis. Histologically, the lesion showed mature plasmacytes, plasmacytoid cells, and large mononuclear cells that exhibited myriad intracytoplasmic crystals. Electron microscopic studies disclosed that the large mononuclear cells, which showed plasmacytic differentiation, contained numerous crystalline inclusions. The crystals were formed within the rough-surfaced endoplasmic reticulum and exhibited a regular periodicity (8 nm). Histochemical methods disclosed that the composition of the crystals was mainly protein (immunoglobulin crystals). Immunoperoxidase techniques for demonstration of immunoglobulins showed that the crystalline inclusions contained IgG. The results of immunohistochemical findings correlated with the results of immunoelectrophoresis of the patient's serum.

Adolescent↗
PubMed1980

Trichilemmoma of eyelid and eyebrow. A clinicopathologic study of 31 cases.

Thirty-one cases of trichilemmoma of the eyelid and eyebrow were studied. All lesions were solitary, small, and asymptomatic. Unlike basal cell carcinoma of the eyelid, trichilemmoma rarely involves the lid margin or the inner canthus. The age range of our patients was from 22 to 88 years old (mean, 56 years). There were 19 men and 12 women. The most frequent clinical diagnoses were verruca vulgaris and cutaneous horn. Typically, the tumor displayed a lobular pattern and was composed mostly of glycogen-rich clear cells. The periphery of the lobules showed palisading of columnar cells and a distinct basement membrane. Histologically, the tumor was frequently misinterpreted as basal cell carcinoma. Review of the literature, including our own series, discloses that the eyelid is the second most common site for trichilemmoma after the nose.

Adult↗
PubMed1980

Corneal crystalline deposits associated with dysproteinemia. Report of two cases and review of the literature.

Two patients had multiple, fine, polychromatic corneal crystals on ocular examination. Peripheral corneal biopsies and electron microscopic studies demonstrated that the crystals, which were located solely within the cytoplasm of keratocytes, exhibited an internal periodicity of 10 nm and developed within dilated cisternae of rough-surfaced endoplasmic reticulum. Histochemical studies of the corneal crystals confirmed their proteinaceous nature (immunoglobulin crystals). Serum protein analysis showed that both patients had a monoclonal gammopathy with an elevated IgG level and increased K light chains. The associated proteinopathy was unsuspected in both patients until the nature of the crystals was established. Both patients had a neoplastic process; one had a previous diagnosis of Hodgkin's disease, and multiple myeloma developed in the other on follow-up studies. Clinicians should be aware of the possibility of a malignant disorder in patients with corneal crystal-line deposits.

Adult↗
PubMed1980

Subcutaneous dirofilariasis of the eyelid and ocular adnexa. Report of six cases.

Six cases of subcutaneous dirofilariasis are reported, three located in the eyelid, two in the periorbital region, and one in the subconjunctival tissues. Three patients lived in Florida, two in North Carolina, and one in Mississippi. All patients were adults, ranging from 27 to 69 years of age (median age was 58 years). Most patients experienced an inflamed painful nodule that contained portions of a nematode. The morphologic features for identification of the worm as belonging to the genus Dirofilaria are outlined.

Adult↗