Search

Animal models of osteonecrosis of the femoral head are indispensable to the understanding of successful treatment modalities for avascular necrosis of the femoral head in adults and in children with Legg-Calvé-Perthes disease. Many of these models adequately reflect the current “vascular deprivation” theory regarding the etiology of the disease. In addition to spontaneous occurrence, surgical- and corticosteroid-induced models are suitable, common experimental ones. Osteonecrosis of spontaneously hypertensive rats appears to be due to defective bone formation and compression of the arteries entering the femoral head at its lateral facets by daily weight-bearing loads. Successful modeling of surgical-induced femoral capital necrosis can be a challenge in animals with a dual epiphyseal blood supply. High doses of corticosteroids are a pivotal risk factor in the development of osteonecrosis. The pathogenesis of corticosteroid-induced osteonecrosis likely resides in reduced blood flow. Steroids may reduce blood flow by numerous mechanisms, including marrow adipocytic hypertrophy leading to sinusoidal compression, venous stasis and, eventually, obstruction of the arteries, and arterial occlusion by fat emboli and lipid-loaded fibrin-platelet thrombi. Other, less common varieties of osteonecrosis include those secondary to endotoxin-induced disseminated intravascular coagulation, immune reactions, immoderately low or high temperatures, and high-impact-related injuries. Common to these diverse forms of osteonecrosis are fibrin thrombi clogging arterioles and small arteries.

Progressive diaphyseal dysplasia is a rare osteosclerotic dysplasia of the bone which presents clinically with bone pain, muscle weakness and a waddling gait. Radiography, which shows progressive hyperostosis along the long bones forms the basis of the diagnosis. We present a young patient in whom pain and limitation of movement in the shoulder joint area, mimicking capsulitis, were the presenting symptoms of the disease. The diagnostic and the therapeutic approach to this unusual disorder are discussed.

The patellae of 6 male and 2 female, 40 to 70 year-old individuals, who were healthy at the time of their violent death, were assessed by computer-assisted image analysis. The means of the bone density (percentage of bone in the respective field of interest) ranged from approximately 20% to approximately 30% in the central spongiotic zones, from approximately 40% to approximately 80% in the superior and inferior peripheral zones, and approximately 40% to approximately 60% in the subchondral zone. Bone densities were greatest in the lateral parts of the subchondral and spongiotic territories. The bony trabeculae were haphazardly distributed in the central spongiotic zones. They were commonly oriented vertically or parallel to the surface of the patella in the peripheral and subchondral zones. In conclusion, the histomorphometric data presented validate the rationale of reaming the articular aspect of the patella into a dome-shaped configuration with preservation of a circumferential bony bulwark in the preparation for the implantation of a thick polyethylene-based component with a concave undersurface.

Purpose: The aim of this work was to detect nuclear parameters related to the prognosis of patients with stage III, IV or DS neuroblastomas. Methods: Histological sections of 25 operation specimens obtained from children with advanced-stage neuroblastomas were subjected to computer-assisted image analysis. Statistical relationships between nuclear descriptors of the tumor cells and patients' clinical outcome were determined. Results: The coefficient of variability of the mean nuclear area the mean nuclear elongation factor, and the mean nuclear averaged Feret diameter of the neuroblastoma cells were ascertained to be discriminators separating high-grade from low-grade tumors. Conclusions: The histomorphometrically gauged nuclear parameters may help oncologists to assess the prognosis of patients with advanced-stage neuroblastoma.

To explore the potential of histomorphometric analysis in distinction between follicular adenomas and well differentiated follicular carcinomas of the thyroid gland. Their differentiation on routine histological study may be a challenging exercise, being contingent upon the absence or presence of vascular invasion and penetration of neoplastic follicles through the capsule of the tumour.Computer-assisted image analysis was performed to gauge the nuclear area, nuclear Ferret diameter, nuclear regularity factor, nuclear elongation factor, number of nuclear vesicles and total area of all nuclear vesicles in the follicles of 37 adenomas and 36 well differentiated carcinomas. By univariate analysis, these nuclear descriptors (with the exception of the elongation factor) were found to correlate with the benign or malignant nature of the tumours. By multivariate analysis, only the nuclear area, Ferret diameter and regularity factor were ascertained to be significant predictors of malignancy. A fitted logit model correctly predicted 91% of the cancers and 87% of the adenomas.Histomorphometrically gauged nuclear parameters of the tumour cells may reinforce pathologists' decision-making by adding objective and unbiased criteria to their subjective assessment of follicular neoplasms in cases in which vascular or capsular invasion are not detected.

The nuclear parameters of the small lymphocytes in nine cases of small cell lymphomas of the thyroid gland and 17 cases of Hashimoto's thyroiditis were assessed by computer-assisted image analysis. The nuclear area, maximal, minimal and averaged Ferret diameters, perimeter, regularity factor and elongation factor were gauged. Statistically, the nuclear area was ascertained to be the optimum descriptor discriminating between small neoplastic and reactive lymphocytes. Application of a novel variable, combining a nuclear area cut-off value of 14 microm2 with a nuclear averaged Ferret diameter cut-off value of 4.5 micron, allows for the distinction - with a high degree of sensitivity and specificity - between small neoplastic lymphocytes in thyroidal lymphomas and the reactive lymphocytes in Hashimoto's thyroiditis.

Efficient tamoxifen treatment of breast cancer patients depends on the degree to which pathologists are consistently able to use the so-called "modified quickscore" method to differentiate between negative and low-grade positive scores based on the current four-grade scale of the estrogen receptor (ER) status of the tumors.To quantitatively test pathologists' ability to adequately render correct readings of the ER status of breast tumors.The ER status of breast carcinomas was estimated by two pathologists and measured by computer-supported analysis in sections stained with ER antibody by the immunoperoxidase technique. Levels of agreement between the examiners' semiquantification and histomorphometrically gauged measurements were compared statistically.The kappa coefficients were 0.28 on a case-by-case collation of the grades of nuclear staining, 0.52 on applying binary categories of positively versus negatively stained cell nuclei, and 0.89 using binary categories with a weighted score of 1.2 to separate ER-negative from ER-positive breast carcinomas.The findings suggest that an optimum rating system is achieved by assigning tumors with a weighted score of 1.2 or less to the ER-negative and those with a weighted score of 1.3 or more to the ER-positive category of breast carcinomas.

A 40y old woman with primary Sjögren's syndrome developed elevated purpura, peripheral neuropathy, muscular tenderness, abdominal pain, heart failure, and convulsive spells. The hallmarks of this disease were high titers of anti-Ro antibodies and low complement levels in the serum, leukocytoclastic small vessel vasculitis in the cutaneous biopsy specimen, and a life threatening clinical course. Echocardiography revealed left ventricular hypokinesis with low ejection fraction, which is unlike the more common features of cardiomyopathy complicating Sjögren's syndrome. The rapidly deteriorating heart failure and other systemic complications remitted on pulse corticosteroid and cyclophosphamide therapy. The pathogenesis of heart failure, which appeared concurrently with vasculitis and was reversed on immunosuppressive therapy, is explained in the context of the systemic disease. Leukocytoclastic vasculitis might be at the origin of this rare variant of acute, severe but reversible cardiomyopathy in pSS.

Nuclear parameters were assessed by computer-assisted image analysis in the cells of abnormal epithelial formations in the acquired cystic kidneys of two dialysis patients, the proximal and distal tubules of a normal kidney and two well differentiated renal cell carcinomas. One acquired cystic kidney contained many small clear celled foci and am 0.9 cm-size clear celled lesion and the second one a papillary microadenoma. The clear celled lesion was cytologically indistinguishable from the carcinomas. The histomorphometrically gauged nuclear parameters were maximal and minimal ferret diameters, averaged ferret diameter, aspect ratio, shape factor, area, volume and specific length and width. Statistical evaluation evidenced that the nuclear area, volume, aspect ration and shape factor allowed for the distinction between benign and malignant epithelial structures. The medians of the nuclear parameters of atrophic tubules, cysts, clear celled foci, papillary adenoma and clear celled lesion in the two acquired cystic kidneys deviation from those of normal renal tubules and in, increasing order of disparity, approached those of the carcinomas.

Qualitative and semiquantitative features of the interfacial membranes of five long-term (16 years) surviving cemented total hip arthroplasties (four revision cases and one autopsy case) were compared with those of thirty short-term surviving (15 years) cemented hip prostheses. Cement granulomas, micron-sized polyethylene particles-induced giant-celled granulomas, sheets of submicron-sized polyethylene particles-laden macrophages, and aggregated, metallic particles-laden macrophages were scattered in the fibrous tissue of all interfacial membranes. Quantitatively, characteristics of the interfacial membranes of the two groups differed from one another. The dominant species of prosthetic debris in the interfacial membranes of the short-term surviving joint replacements was derived from the polyethylene acetabular socket, and, correspondingly, giant-celled granulomas and macrophagic sheets predominated. Metallic particles and the macrophagic reaction thereto dominated in the interfacial membranes of the long-term surviving arthroplasties, and large cement and polyethylene chunks typically were incorporated in the fibrous tissue of the membranes without an accompanying macrophagic response. In long-term surviving hip arthroplasties, metallic particles may be at least as important as polymeric detritus in stimulating the formation of the bone-resorbing, granulomatous interfacial membrane, which is the hallmark of aseptically loosened arthroplasties. Differences in mechanical settings may account for unlike modes and rates of generation of prosthetic breakdown products, explaining the disparate survivorship of different patients' artificial joints.

The clinical presentation of acute appendicitis and the idiopathic granulomatous variety are, as a rule, indistinguishable. Five patients with idiopathic granulomatous appendicitis, treated during past decade, had histological acute and chronic appendicitis abounding with granulomas. Investigations not disclosing a systemic or enteric granulomatous disease and the patients' long-term complete postoperative recovery support the diagnosis of idiopathic granulomatous appendicitis.

An elderly woman underwent jejunectomy for a large, stenosing neoplasm. Histologically, we found an undifferentiated carcinoma with scattered mononuclear and multinuclear macrophages in the intestine and lymph node metastases. The multinuclear cells, being acid phosphatase-positive and CD68-immunoreactive, are referred to as osteoclast-like giant cells. Hepatic secondaries were discovered 6 months postoperatively. The patient succumbed to a chemotherapy-related septic event. We suggest that intratumoral infiltration by mononuclear and multinuclear macrophages expresses one of the body's defense mechanisms against cancer.

A 59-year-old patient is reported with a protruding, mucosal nodule within the mandibular alveolar fold. Histological examination of the excised mass disclosed angiolymphoid hyperplasia with eosinophilia (histiocytoid hemangioma). Though the lesion was not completely excised and invaded the adjacent muscle of the floor of the mouth, there was no recurrence during a follow-up period of 17 months.

Thirty-six interfacial membranes collected at the time of removal of intramedullary L316 stainless steel nails were studied histologically. The membranes consisted of bland fibrous tissue in a minority of cases. Most often, the nails were enclosed within a synovial-like membrane. Palisading macrophages and fibroblasts abutted on the metallic surface of the nails. Foreign body giant-celled granulomas were scattered in the midzone of the membranes, mono- and polykaryonic macrophages having phagocytozed small metallic particles, necrotic bony debris, and, sometimes, lipidic compounds. Aggregates of hemosiderin-containing macrophages occasionally marked the sites of previous hemorrhages. When present in the retrieved specimen, the bone underlying the membrane was undergoing remodeling. Interfacial motion, consequent on dissimilar stiffness of the bone and nail, as well as deposition of metallic and bony debris, are likely responsible for the formation of the synovial-like interfacial membrane.

The histological features of lipodermatosclerosis and eosinophilic fasciitis and its variants were compared in a prospective study of outpatients attending the vascular clinic and inpatients in the Department of Medicine of a regional university hospital. Main outcome measures examined were swelling and induration of the subcutaneous layers with a stocking distribution in the calves. The inflammatory and fibrosing alterations involving the panniculus adiposus, superficial fascia and perimysium were essentially indistinguishable histologically in patients with lipodermatosclerosis or eosinophilic fasciitis and its variants. The intensity of the subcutaneous induration was related to the underlying nosological entity and the duration of the process. Infectious cellulitis was found to aggravate the clinical symptoms of lipodermatosclerosis. Since the stereotypical inflammatory and fibrosing processes in lipodermatosclerosis and eosinophilic fasciitis and its variants are similar irrespective of the initiating factors, it is suggested that there is a common final pathway in the pathogenesis of both disorders.

A leiomyoma of the fetal membranes was incidentally discovered on examination of a spontaneously expulsed placenta following an uneventful pregnancy and delivery of a healthy neonate. Perusal of the literature uncovered only a single report of a placental leiomyoma.