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Biomedical subjects

M Killingsworth

Publications and source records attributed to M Killingsworth.

12 recordsLinked to original sources
PubMed2006

Development of atrophy of the retinal pigment epithelium around disciform scars.

BACKGROUND/AIMS: Eyes with burnt out disciform scars secondary to age related macular degeneration (AMD) are regarded as visually stable. The aim of this study is to report the subsequent development of atrophy of the retinal pigment epithelium (RPE) around the scars and discuss the possible basis. METHODS: 20 eyes from 18 patients were observed to develop atrophy around choroidal neovascularisation (CNV). A method of measuring expansion of the atrophy over time is described using the Topcon Imagenet 2000 system. An additional 10 clinicopathological examples were reviewed. RESULTS: Clinically CNV became surrounded initially by a ring of pallor that progressed to an expanding band of atrophy of the RPE. It developed most rapidly in the first 3 years after CNV became quiescent but then continued to expand slowly to more than three times the size of the scar. Histopathological specimens showed large choroidal vessels entering the scars directly and a reduced number of small choroidal vessels beneath and around the scar CONCLUSIONS: Disciform scars may become surrounded by an expanding band of atrophy of the RPE, postulated to result from remodelling of the choroidal circulation. The ongoing enlargement of the resulting scotoma may need to be considered when planning management and assessing treatment outcomes.

Aged↗
PubMed2001

Necrotizing infundibular crystalline folliculitis.

We describe a 22-year-old woman with a background of acne who developed multiple folliculocentric facial papules associated with sharply demarcated waxy, keratotic plugs. Multiple skin biopsies showed umbilicated craters that were filled with dispersed bundles of eosinophilic filaments embedded in a pale amorphous matrix forming a plug. The plugs bulged into the upper dermis. Serial sections showed vacuolar and filamentous destruction of the infundibular and adjacent perifollicular epithelium and a close relationship of the crystalline necrosis to follicles. Electron microscopy revealed that the filamentous bundles were tonofilaments. No fresh material was available for polarization and the paraffin sections failed to polarize. The clinical and pathological findings of the lesions in our patient were identical to those reported as a new perforating disorder with urate-like crystals. Our case indicates that the process may represent crystalline folliculocentric necrosis rather than a primary perforating disorder. The nature and basis of the crystals that have a urate-like appearance remain to be determined.

Adult↗
PubMed2001

Cystadenoma of the seminal vesicle: report of a case with ultrastructural findings.

Cystadenomas of the seminal vesicles are extremely rare benign tumours. We have not been able to find more than 10 cases in the literature. A benign cystadenoma of the seminal vesicle is described in a 49-year-old man. The clinical presentation, gross appearance, microscopic characteristics, immunohistochemical and ultrastructural findings of this uncommon tumour are discussed. The purpose of this paper is to report an unusual case of cystadenoma of the seminal vesicle and review the 10 previously reported cases in the English literature.

Biomarkers, Tumor↗
PubMed2000

Lipid and giant cell poor necrobiotic xanthogranuloma.

An 88-year-old man over a 7-month period developed multiple yellow firm focally ulcerative papules and nodules over his face, neck and forearms. Seven skin biopsies showed a diffuse infiltrate of epithelioid histiocytes associated with areas of necrosis with neutrophilia. Two biopsies showed xanthogranulomatous foci, but cholesterol clefts, prominent giant cells or lymphoid aggregates were not evident. Necrosis with leukocytoclastic debris overshadowed the presence of hyaline necrobiosis. Ultrastructural examination and oil red-o stains on frozen sections revealed focal lipid vacuoles within histiocytes. A paraprotein was detected in the patient's serum. This presentation may represent a lipid and giant cell poor variant of necrobiotic xanthogranuloma (NXG) and may potentially lead to a delay in diagnosis.

Aged↗
PubMed1999

Hereditary progressive mucinous histiocytosis.

We describe a 61-year-old woman who presented with multiple small, firm, shiny, skin-coloured papules in a symmetrical pattern on the dorsum of the hands, sides of the fingers and extensor aspect of the forearms. These had slowly increased in number over a period of 40 years, and were asymptomatic. Both laboratory results and systemic review were unremarkable. Histological examination of six papules revealed well-circumscribed but unencapsulated dermal nodules composed of epithelioid histiocytes and abundant alcian blue-positive mucin separating broad bundles of collagen. Histiocytes within the nodule stained positively with vimentin, and were focally positive for alpha1-antitrypsin and lysozyme. The interstitium was positive for tenascin. On electron microscopy, the histiocytes showed numerous circular, osmophilic myelin bodies and zebra bodies reminiscent of those seen in lysosomal storage diseases. Our patient's clinical, histological and ultrastructural features have been previously described as hereditary progressive mucinous histiocytosis, a rare familial form of eruptive histiocytoma characterized by multiple persistent papules with prominent mucinosis.

Disease Progression↗
PubMed1995

Merkel cell carcinoma with a desmoplastic portion.

Merkel cell carcinoma of the skin usually has a trabecular, intermediate-cell or small-cell pattern of differentiation. We report the case of a 66-year-old man who developed a progressive multinodular plaque that showed a prominent desmoplastic component on preliminary biopsy. Immunohistochemical and ultrastructural studies and the final surgical specimen confirmed that the tumor was a Merkel cell carcinoma. The presence of desmoplasia may mask the diagnosis of Merkel cell carcinoma.

Aged↗
PubMed1995

Basaloid folliculolymphoid hyperplasia with alopecia as an expression of mycosis fungoides (CTCL).

Follicular mucinosis, papules, cysts and comedones have been previously described as expressions of follicular involvement by mycosis fungoides. We report a patient with mycosis fungoides who developed extensive alopecia. Multiple scalp biopsies showed perifollicular and intrafollicular infiltrate of lymphocytes but no evident follicular mucinosis. On transverse sections many of the follicles showed an absence of differentiation towards hair sheath, canal, sebaceous gland or hair formation, but instead formed undifferentiated basaloid structures. These basaloid structures showed transition from atrophic telogen follicles to hypertrophic basaloid islands infiltrated by lymphocytes, resembling the pattern previously described in cutaneous lymphadenoma. Immunophenotyping showed a predominance of helper T-cells which, on ultrastructural examination, showed cerebriform nuclei. The unusual histological findings in our case may be analogous to the hyperplasia seen in sweat glands in syringotropic mycosis fungoides (syringolymphoid hyperplasia), and we propose the term basaloid folliculolymphoid hyperplasia to describe this feature. Basaloid follicular hyperplasia has been previously described as a component of follicular mucinosis but may apparently develop in the absence of overt mucinosis.

Aged↗
PubMed1995

Raimer's bands: case report with a review of solar elastosis.

Raimer's solar elastotic bands of the forearm are a rarely described clinical variant of severe solar elastosis. We report a case of Raimer's bands on the forearm of a 43-year-old woman. Light microscopy demonstrated solar elastosis and electron microscopy revealed activated fibroblasts appearing to secrete the elastotic material. The clinical variants of solar elastosis are outlined and the possible pathogenesis of the elastotic material is discussed.

Adult↗
PubMed1985

Retinal changes in myotonic dystrophy: a clinicomorphological study.

This report appears to be the first ultrastructural study of the maculopathy and peripheral pigmentary retinopathy in myotonic dystrophy. Nine eyes from five patients observed during life are described. The findings were similar in all eyes, the retinal pigment epithelium in the macular region containing an accumulation of lipofuscin in large hyperpigmented cells. Pigment-laden profiles found in the subpigment epithelial space or subretinal space were interpreted as an attempt to discharge the pigment. Stress fibres of actin microfilaments were thrown into prominence by the irregularity of the pigment epithelium. In the periphery migration of retinal pigment cells into the retina occasionally resulted in the formation of bone corpuscles around occluded vessels, as occurs in retinitis pigmentosa; but more often the clumps were coarser and surrounded basement membrane material. Central and peripheral epiretinal membranes were also observed.

Cataract↗
PubMed1984

An ultrastructural study of the role of leucocytes and fibroblasts in the breakdown of Bruch's membrane.

Ultrastructural examination was performed on 30 eyes selected on the basis of a light microscopic classification as representing all stages of macular degeneration. The eyes belonged to 29 patients aged 40 to 91 years at death and all patients with the exception of the 40-year-old had been examined during life. The results indicate that monocytes, lymphocytes, fibroblasts and mast cells may play a role in the formation of breaks in Bruch's membrane at early and late stages of macular degeneration. The implications of these observations are discussed in the context of their possible role in choroidal neovascularization.

Adult↗
PubMed1980

Softening of drusen and subretinal neovascularization.

On the basis of clinico-pathological examination, drusen were divided into hard and soft. A few small, hard drusen with a hyaline composition were found in 50 per cent of the normal aged eyes examined. The appearance of drusen of softer consistency often heralded the onset of senile macular degeneration. Soft drusen resulted either from the breakdown of the hyaline content of hard drusen or from the focal aggregation into mounds of membranous debris which accumulated as a widespread shallow layer between the basement membrane of the pigment epithelium and Bruch's membrane. Softening of drusen was most evident when the retinal pigment epithelium demonstrated the greatest proliferative activity, with migration of cells into the retina and the formation of the basal laminar deposit. It was at this stage that subretinal neovascularization was first detected. A patient in whom the gradual development of small soft drusen and an associated pigmentary disturbance was followed by subretinal new vessel formation is reported. The eye was subsequently found to have five separate breaks in Bruch's membrane and the ultrastructural findings are described.

Aged↗