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Biomedical subjects

R L Font

Publications and source records attributed to R L Font.

At least 145 records · Page 8Linked to original sources

Amputation neuroma of the orbit. Report of two cases and review of the literature.

Two patients developed proptosis and a slowly enlarging mass with increasing discomfort in the orbital socket 17 and 25 years following enucleation. Preoperative CT scans revealed a single cystic structure within the orbits of each case with distinct soft tissue tumors adjacent to the cysts. The cystic structures and the adjacent solid masses were removed en bloc necessitating reconstruction of the orbits with a dermal fat pad (case 1) and a mucous membrane graft (case 2). Postoperatively the patients were free of complaints. Microscopically, the cystic structures were identified as conjunctival inclusion cysts while the soft tissue masses were traumatic neuromas with irregular tangles and whorls composed of proliferated axons, Schwann cells and connective tissue. Only seven amputation neuromas of the orbit have been reported. Pain related to the neuroma is rarely encountered and is probably caused by mechanical irritation of the amputation neuroma, by retracting scar tissue, or compression from an adjacent cystic mass as in one of our cases.

Adult↗

Malignant syringoma of the eyelid.

Two cases of malignant syringoma of the eyelid are reported. The first patient, a 20-year-old woman, presented with a one year history of a slowly growing nodule in the left lower eyelid. The lesion recurred five months after excision, slowly grew over the ensuing two and one-half years, and was reexcised. The second case was an 18-year-old man who was first examined by an ophthalmologist because of a slowly enlarging, painless induration of his right lower eyelid for two years. Histologic examination of the excised lesions from both patients disclosed proliferated ducts lined by two layers of epithelium infiltrating the dermis and subcutaneous tissue; there was skeletal muscle and perineural invasion, but only minimal cellular atypia. Malignant syringomas are rare forms of sweat gland carcinoma, which most often occur on the upper lip and to our knowledge have not been reported on the eyelid. These tumors probably arise from eccrine ducts, are more common in women, and have a peak incidence in the fifth decade. The histologic feature that best indicates prognosis is the degree of cellular atypia. Patients with cytologically well-differentiated tumors do well following complete local excision. Features that help to distinguish malignant syringoma from its benign counterpart are the larger size, solitary nature, and subcutaneous, muscular, and perineural invasion.

Adenoma↗

Applications of immunohistochemistry to ophthalmic pathology.

Immunohistological techniques have been increasingly used, both in general and ophthalmic pathology, for identification of specific cell types that may not be possible on morphological grounds or by conventional histochemical methods alone. Enzyme conjugate techniques using the peroxidase-antiperoxidase (PAP) immune complex method and the avidin-biotin-horseradish peroxidase method (ABC) are particularly useful as they are highly sensitive, provide permanent results, allow the use of paraffin-embedded tissues and do not require a fluorescent microscope. Antibodies against glial fibrillary acidic protein (GFAP), factor VIII-related antigen, muramidase, S-100 protein, myoglobin, prostatic acid phosphatase and prostate-specific antigen are valuable tools in surgical pathology and their applicability to ophthalmic pathology have been clearly demonstrated.

Acid Phosphatase↗

Melanotic schwannoma of soft tissues. Electron-microscopic observations and review of literature.

This is a report of an unusual case of melanotic schwannoma located in the soft tissue of the shoulder. By light microscopy, the partially pigmented, encapsulated mass showed tumor lobules displaying an organoid pattern and benign cytologic features. By electron microscopy, the tumor cells disclosed numerous interdigitating blunt cytoplasmic processes invested by a thin, continuous basal lamina with formation of mesaxons and moderate amount of glycogen as well as immature and mature melanosomes. The patient was reported to be alive and well 7 years after local excision of the mass. We also reviewed 21 additional cases from the literature. The most frequent sites of involvement were: the spinal nerve roots and adjacent structures (12 cases), soft tissues (five cases), heart (one case), esophageal wall (one case), acoustic nerve (one case), and mandible (one case). Twelve patients were alive and well (follow-up periods ranging from 9 months to 13 years after surgical resection), and one died of surgical complications. Eight patients were lost to follow-up. Three patients had local recurrences due to incomplete excision of the mass. Ten tumors were studied electron microscopically and displayed characteristic features of both Schwann cells and melanocytes. This unique dual differentiation probably reflects their common ancestry from neural crest cells.

Adolescent↗

Metastatic protothecal retinitis in a dog. Electron microscopic observations.

Disseminated protothecosis, due to Prototheca wickerhamii, was present in a two-year-old female dog with a nine-month history of hemorrhagic colitis and diarrhea. Shortly thereafter, the dog developed "acute blindness" of the left eye. Euthanasia was done after medical therapy failed to control the disease. Histologically, the eye had multiple microabscesses and necrotic foci containing myriad protothecal organisms under the detached retina. Numerous organisms also were present in the mucosa and walls of the colon. The identification of P. wickerhamii was confirmed by the histologic appearance and immunofluorescent studies. The ultrastructural features of P. wickerhamii also were studied.

Animals↗

Conjunctival synthetic fiber granuloma. A lesion that resembles conjunctivitis nodosa.

Histopathologic examination of forniceal conjunctival lesions excised from five young patients revealed granulomatous inflammation surrounding filamentous foreign material. Polarization microscopy, special histochemical stains, scanning electron microscopy and energy dispersive x-ray elemental analysis identified the inciting material as predominantly synthetic fabric fiber. Three of these cases initially were diagnosed as conjunctivitis nodosa, an inflammatory reaction to caterpillar setae. Many synthetic fibers contained numerous granules of titanium, barium, or zinc delustering agent, which served to differentiate them from natural fibers or caterpillar hairs. Synthetic fabric fiber is a previously unrecognized cause of conjunctival inflammatory mass lesions.

Adolescent↗

Postradiation leiomyosarcoma of the orbit complicating bilateral retinoblastoma.

A 31-year-old woman had bilateral retinoblastoma diagnosed in early childhood. The right eye was enucleated at the age of 1 year, and the left eye was treated with radiation therapy (a total dose of 16,000 rad). Twenty-three years later, in 1975, a subcutaneous mass was noted in the left periorbital region. A biopsy specimen of the mass was taken and a diagnosis of pleomorphic postradiation sarcoma was made. Electron microscopic studies of the periorbital mass confirmed the diagnosis of leiomyosarcoma. After additional radiation therapy, the residual mass was surgically excised. Five years later, a right renal mass, which histologically proved to be a renal cell carcinoma, was discovered. She was treated with nephrectomy, radiation, and chemotherapy. A recent follow-up examination disclosed that the patient is alive and apparently without any evidence of metastatic disease, 30 years after the diagnosis of bilateral retinoblastoma was made. The literature is reviewed regarding postradiation sarcomas and the occurrence of second malignant neoplasms in patients with retinoblastoma.

Adult↗

Intravascular papillary endothelial hyperplasia of the orbit and ocular adnexa. A report of five cases.

This is a clinicopathologic study of five patients with intravascular papillary endothelial hyperplasia involving the orbit and ocular adnexa. The median age of the patients was 45 years. Three lesions were located in the orbit, one in the eyelid, and one in the eyebrow. Four lesions were located within a distended vein and one involved an artery. The walls of the vessel corresponded to the "capsule" of the circumscribed mass. The lumen disclosed different stages of organization of a thrombus with prominent endothelial cell proliferation centered around cores of collagenous tissue and fibrin. Electron microscopy of one lesion displayed spindle-shaped cells with features of endothelial cells forming a polarized basement membrane with numerous micropinocytotic vesicles on their plasmalemma. Some cells showed ultrastructural features of pericytes. The lesion, which may be confused with angiosarcoma, represents an unusual exuberant proliferation of vascular endothelium as a cellular response to the organization of a thrombus.

Adult↗

Two cases of uveal metastasis from breast carcinoma in men.

We studied two cases of uveal metastasis from carcinoma of the breast in men. One patient was a 51-year-old man who developed ocular symptoms nine months after excision of a breast mass histologically diagnosed as an infiltrating ductal carcinoma. After the patient committed suicide, an autopsy disclosed metastatic lesions to the lungs, mediastinum, and chest wall. The second patient was a 49-year-old man who complained of ocular symptoms three years after undergoing mastectomy for breast carcinoma. One month after the onset of the ocular symptoms, his left eye was enucleated. Metastatic lesions were detected in the lungs and brain. More than one year after undergoing bilateral orchiectomy, and after whole-brain radiation therapy (4,500 rads) and chemotherapy, the patient has no neurologic symptoms. It appears that mammary carcinoma in men has a poorer prognosis than it does in women, probably because of two main factors: the advanced clinical stage of the disease when it is first detected and the more diffuse infiltrating character of the mass because of the scarcity of mammary tissue in men.

Breast Neoplasms↗

Angiolymphoid hyperplasia with eosinophilia (Kimura's disease) of the orbit and ocular adnexa.

We conducted a clinicopathologic study of eight cases of angiolymphoid hyperplasia with eosinophilia (Kimura's disease). The orbit was involved in five patients and the ocular adnexa (eyelid and inner canthus) in three. The median age of the six men and two women was 51 years (range, 38 to 72 years). The lesions were characterized by an abnormal proliferation of small vessels lined by plump endothelial cells, associated with a chronic inflammatory infiltrate with prominent tissue eosinophilia and scattered lymphoid follicles. Serial sectioning of two tumors disclosed that these small vessels apparently originated within the walls of arteries. Immunohistochemistry disclosed factor VIII-related antigen within the endothelial cells in two of the four lesions studied. Ultrastructurally, some of the capillaries showed prominent multilaminar basement membranes surrounding their walls. The apical surface of the markedly swollen endothelial cells disclosed broad villous processes protruding into the lumen. Although this vascular lesion can be mistaken for angiosarcoma, it is considered benign. There was no evidence of recurrences of any of the six of the seven lesions that were completely excised and followed up (follow-up periods ranged from five to 95 months). Complete surgical excision appears to be the best treatment.

Adult↗

Epithelioid angiosarcoma of the orbit presenting as Tolosa-Hunt syndrome. A clinicopathologic case report with review of the literature.

The clinical diagnosis of Tolosa-Hunt syndrome was first considered in a 66-year-old man with facial pain and diplopia. A complete neuroradiologic evaluation as well as an oncologic work-up yielded normal results. Several courses of oral prednisone provided no significant benefit. Within a year the patient became clinically worse and a CT scan disclosed an abnormal area of enhancement at the left orbital apex. An orbital exploration was performed elsewhere and a histologic diagnosis of myositis was obtained. Because of further worsening the patient was re-evaluated 3 months later and a CT scan showed a mass in the left orbital apex and superior orbital fissure. A second orbital exploration was performed and a sausage-shaped mass encompassing the optic nerve was excised. By light microscopy a poorly differentiated malignant tumor was infiltrating the orbital tissues with areas of intra- and perineural invasion. The tumor cells were arranged in strands and tubules with a definite tendency to form lumens that often contained red blood cells. Electron microscopic studies disclosed features consistent with a neoplasm of endothelial cell origin displaying a polarized basal lamina and rare micropinocytotic vesicles on the luminal side. The presence of multiple, slender microvilli and sometimes tonofilaments as well as desmosomes were interpreted as epithelioid metaplasia of an angiosarcoma.

Aged↗

Hamartomatous adenoma of the nonpigmented ciliary epithelium arising in iris-ciliary body coloboma. Light and electron microscopic observations.

A 2 1/2-year-old boy had a slowly enlarging mass at the site of a typical iris-ciliary body coloboma for 2 years. The mass was excised partially by iridocyclectomy. By light microscopy, the tumor cells were embedded in a rich mucoid stroma that contained abundant hyaluronidase-sensitive acid mucopolysaccharides. By electron microscopy the tumor showed light and dark cells with interdigitating cell membranes, desmosomes, gap junctions, multilaminar basement membrane, and numerous extracellular collagen fibrils that resembled vitreous fibrils. We believe that the tumor represents a hamartomatous (congenital) adenoma of the nonpigmented ciliary epithelium rather than a conventional (acquired) adenoma, since it developed precisely within a colobomatous defect of the iris and ciliary body.

Adenoma↗

Medulloepithelioma diagnosed by ultrasound and vitreous aspirate. Electron microscopic observations.

Ultrasonography and cytologic examination of the vitreous aspirate established the correct pre-enucleation diagnosis of medulloepithelioma in the case of an 8-year-old boy. The use of a muscle hook allowed the examiner to elevate the eye and bring the ciliary body into adequate ultrasonographic view. Histopathologic examination of the enucleated eye showed a partially pigmented mass composed of elongated neuroepithelial tubules and cords arising from the ciliary body inferiorly. Several tubules displayed a central lumen with rosette-like structures. The tumor was classified as a benign, nonteratoid medulloepithelioma. Electron microscopically the lumens of the rosettes contained myriad, slender microvilli, and were bordered by numerous terminal bar complexes and areas displaying zonula adherens and zonula occludens type junctions. Additionally, invaginating gap junctions, which clearly established that the tumor originated from the ciliary epithelium, were identified.

Biopsy, Needle↗

Pigmented conjunctival cysts following tetracycline/minocycline therapy. Histochemical and electron microscopic observations.

Unpigmented and pigmented cystic epithelial inclusions were found bilaterally within the lower palpebral conjunctiva temporally of a 31-year-old man. He had a history of tetracycline/minocycline therapy for 14 years because of acne vulgaris. The cysts were studied by light and electron microscopy, histochemistry, and ultraviolet light. By light microscopy the unpigmented cysts contained faintly eosinophilic globular material that disclosed yellowish-green autofluorescence indicating the presence of tetracycline/minocycline. The pigmented cysts revealed laminated eosinophilic to brownish concretions that also showed yellowish-green autofluorescence. Autofluorescence, however, decreased with increasing brown pigmentation of the concretions. Histochemically, the pigment, which failed to show the staining characteristics of lipofuscin, melanin or iron, probably represented an oxidation product of tetracycline. By electron microscopy the cysts contained moderately electron dense amorphous material as well as degenerating epithelial cells. The epithelial cells lining the conjunctival cysts, did not contain membrane-bound, large, pigment granules within their cytoplasm as has been demonstrated in the colloid and follicular epithelium of the thyroid following minocycline therapy.

Acne Vulgaris↗

Bilateral retinal ischemia in Kawasaki disease. Postmortem findings and electron microscopic observations.

A 4-month-old infant died of cardiovascular complications of Kawasaki disease (KD). At autopsy, aneurysmal dilatation with recent thromboses were found in coronary arteries, abdominal aorta, brachial and left common carotid arteries. A vasculitis with thrombosis of a branch of the ophthalmic artery was demonstrated in the right orbital apex. Light microscopy disclosed that the ocular abnormalities were confined to the retinas of both eyes that exhibited inner retinal ischemia. By electron microscopy, the inner retina showed clumping of nuclear chromatin, mitochondrial swelling, rupture of plasma membranes, and increased number of lipid figures. Müller cell processes were intact. Stereologic analysis of the mitochondria in the retinal pigment epithelium, photoreceptor inner segment, and ganglion cells in the KD infant demonstrated that identical mitochondrial changes occurred in the retina from an adult woman who had a recent central retinal artery occlusion.

Adult↗

Light and electron microscopic study of Dalén-Fuchs nodules in sympathetic ophthalmia.

A light and electron microscopic study was undertaken in an effort to establish the origin of the "epithelioid" cells in Dalén-Fuchs nodules from an eye enucleated because of sympathetic ophthalmia. The nodules were visible as minute (130-160 microns), round, grayish-white mounds elevating the retinal pigment epithelium. Bruch's membrane appeared intact in all the sections examined. By electron microscopy the "epithelioid" cells had round to oval nuclei with abundant, relatively lucent cytoplasm containing parallel profiles of rough-surfaced endoplasmic reticulum, prominent Golgi lamellae, clusters of polyribosomes, and scattered mitochondria. Many interdigitations of the plasma membranes, some of which exhibited fascia adherens type attachments, were observed. Some cells within the nodules showed large membrane-bound phagosomes containing laminated structures. Other "epithelioid" cells displayed moderately electron dense membrane-bound granules that appeared to be early precursors of lipofuscin granules. Examination of the nodules under ultraviolet light showed myriad autofluorescent yellowish-orange dots consistent with lipofuscin. Additionally, a montage of electron micrographs from the edge of the nodule, coupled with the above findings, provided support to the concept proposed by Ishikawa and Ikui (1972) that the "epithelioid" cells in Dalén-Fuchs nodules represent transformed retinal pigment epithelial cells forming a cage-like framework within the nodule. This study also emphasizes the remarkable capabilities for differentiation by the retinal pigment epithelial cells.

Female↗

Canine protothecosis: review of the literature and report of an additional case.

A review of protothecosis in dogs revealed that this malady usually begins in the gastrointestinal tract and progresses to systemic involvement. Clinical signs generally include bloody diarrhea or blood-stained feces as well as blindness, ataxia, and polyuria. Histologically, myriads of protothecal organisms in different stages of development are found in the granulomatous lesions. Two main species have been culturally identified: Prototheca zopfii and P wickerhamii. In the absence of cultural studies, species identification can be accomplished readily by immunofluorescence. The present case involved P zopfii infection in a 5-year-old female Cocker Spaniel that had bloody diarrhea, with a history of bloody diarrhea 6 months earlier.

Animals↗

Bilateral diffuse melanocytic uveal tumors associated with systemic malignant neoplasms. A recently recognized syndrome.

Four cases of the simultaneous occurrence of bilateral diffuse melanocytic uveal tumors were studied by us. In each case, the patient had an associated systemic malignant neoplasm diagnosed by biopsy or at autopsy. There was no evidence of metastatic melanoma in any patient. Clinically, the patients experienced rapid loss of vision, and cataracts were usually present. Multiple pigmented and nonpigmented placoid iridic and choroidal nodules, as well as serous retinal detachment, frequently were noted. Histopathologically, the uveal tracts of both eyes were diffusely infiltrated by preponderantly benign-appearing nevoid or spindle-shaped cells. Areas of necrosis within the tumors and scleral involvement were commonly seen. We believe this constellation of findings constitutes a new syndrome in which there is a bilateral, diffuse proliferation of melanocytic cells throughout the uvea in association with a systemic malignant neoplasm.

Adenocarcinoma↗