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BACKGROUND: The clinical significance of pericardial biopsy is controversial. The aim of this study was to assess the feasibility and diagnostic value of 3 approaches to pericardial biopsy: fluoroscopic control and standard sampling, pericardioscopy guidance with standard sampling, and pericardioscopy guidance with extensive sampling. METHODS AND RESULTS: Forty-nine subsequent patients with a large pericardial effusion underwent parietal pericardial biopsy. In group 1 (12 patients, 66.7% males, age 46.7+/-12.2 years), pericardial biopsy was guided by fluoroscopy (3 to 6 samples per patient). Group 2 included 22 patients (50% males, age 50.8+/-10.4 years) undergoing 4 to 6 pericardial biopsies per patient guided by pericardioscopy (16F flexible endoscope). In group 3, extensive pericardial sampling was performed, guided by pericardioscopy (15 patients, 53.3% males, age 53.7+/-12.8 years, 18 to 20 samples per patient). Sampling efficiency was better with pericardioscopy (group 2, 84.9%; group 3, 84.2%) compared with fluoroscopic guidance (group 1, 43.7%; P<0.01). Diagnostic value was defined as a new diagnosis uncovered, etiology revealed, clinical diagnosis confirmed, and the biopsy false-negative. Pericardial biopsy in group 3 had higher diagnostic value than in group 1 in revealing new diagnosis (40% versus 8.3%, P<0.05) and etiology (53.3% versus 8.3%, P<0.05). In group 2, pericardial biopsy had a higher yield in establishing etiology than in group 1 (40.9% versus 8.3%; P<0.05). Pericardial biopsy was false-negative in 58.3% in group 1 in contrast to 6.7% in group 3 (P<0.01). There were no major complications. CONCLUSIONS: Pericardioscopic guidance enhanced pericardial sampling efficiency. The diagnostic value of pericardial biopsy was significantly improved by extensive sampling made possible by pericardioscopy.
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Biopsia/instrumentación , Biopsia/métodos , Derrame Pericárdico/patología , Pericardio/patología , Biopsia/efectos adversos , Endoscopía , Estudios de Factibilidad , Femenino , Fluoroscopía , Humanos , Masculino , Persona de Mediana Edad , Pericarditis/patología , Pericardio/diagnóstico por imagenRESUMEN
BACKGROUND/AIM: The heart has traditionally been considered as a static organ without capacity of regeneration after trauma. Currently, the more and more often asked question is whether the heart has any intrinsic capacities to regenerate myocytes after myocardial infarction. The aim of this study was to present the existence of the preserved muscle fibers in the myocardial scar following myocardial infarction as well as the presence of numerous cells of various size and form that differently reacted to the used immunohistochemical antibodies. METHODS: Histological, histochemical and immunohistochemical analyses of myocardial sections taken from 177 patients who had died of acute myocardial infarction and had the myocardial scar following myocardial infarction, were carried out. More sections taken both from the site of acute infarction and scar were examined by the following methods: hematoxylin-eosin (HE), periodic acid schiff (PAS), PAS-diastasis, Masson trichrom, Malory, van Gieson, vimentin, desmin, myosin, myoglobin, alpha actin, smoth muscle actin (SMA), p53, leukocyte common antigen (LCA), proliferating cell nuclear antigen (PCNA), Ki-67, actin HHF35, CD34, CD31, CD45, CD45Ro, CD8, CD20. RESULTS: In all sections taken from the scar region, larger or smaller islets of the preserved muscle fibers with the signs of hypertrophy were found. In the scar, a large number of cells of various size and form: spindle, oval, elongated with abundant cytoplasm, small with one nucleus and cells with scanty cytoplasm, were found. The present cells differently reacted to histochemical and immunohistochemical methods. Large oval cells showed negative reaction to lymphocytic and leukocytic markers, and positive to alpha actin, actin HHF35, Ki-67, myosin, myoglobin and desmin. Elongated cells were also positive to those markers. Small mononuclear cells showed positive reaction to lymphocytic markers. Endothelial and smooth muscle cells in the blood vessel walls were positive to CD34 and CD31, and smooth muscle cells to SMA. Oval and elongated cells were positive to PCNA and Ki-67. The preserved muscle fibers in the scar were positive to myosin, myoglobin and desmin as well as elongated and oval cells. Other cells were negative to these markers. CONCLUSION: Our findings speak that myocardial regeneration is maybe possible and develops in human ischemic heart damages and that the myocardium is not a static organ without capacity of cell regeneration.
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Cicatriz/metabolismo , Infarto del Miocardio/metabolismo , Miocardio/química , Anciano , Cicatriz/etiología , Cicatriz/patología , Femenino , Histocitoquímica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Infarto del Miocardio/patología , Miocardio/patologíaRESUMEN
INTRODUCTION: Primary heart tumors are very rare. They can be benign and malignant. Benign ones make about two thirds of all heart tumors. However, they are benign only by their biologic characteristics, but potentially malignant by their localization. About three forths of benign tumors are myxomas. Their growth is usually slow and they can be for a long time silent, particularly if they do not compromise vital functional parts of the heart. Myxomas grow in the atria, mostly in the left one and very rarely in the ventricles. CASE REPORT: We presented two patients with myxomas in the left, and, in the right atrium which are representative samples of the most common localization of heart myxoma considering previous knowledge of these tumors. Analysis of the clinical course in the two presented patients with characteristic localizations showed general characteristics of the clinical course of heart myxoma. The patients did not have characteristic symptoms for a rather long period of time and the findings obtained by standard examinations did not raise suspicion of heart tumor. Pulmonary symptomatology in one patient and cardial in the other, when tumor had already occupied almost the entire atrium, suggested necessity of cardiologic examination. Indication for operation was in both patients confirmed after performed echocardiography, computed tomography of the thorax and angiography with ventriculography. The size of the removed atrial tumors and their localization explained some of the patients' troubles, but it was also amazing that they had not caused more serious problems. Operation as the only method of treatment was successful in both female patients and its effect was permanent. At annual controls neither recurrence of the tumor nor troubles possibly associated with it were observed. CONCLUSION: Patients with heart myxoma usually pass through asymptomatic or oligosymptomatic phase, but when troubles become manifested, they do not much differ from those due to other causes. For this reason this tumor can be diagnosed just when complications caused by its localization and growth develop. Modern cardiologic diagnostics, primarily preventive non-invasive echocardiography, enables timely diagnosis and removal of the tumor because only then it may take a name benign tumor.
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Neoplasias Cardíacas/cirugía , Mixoma/cirugía , Femenino , Atrios Cardíacos , Neoplasias Cardíacas/diagnóstico , Humanos , Persona de Mediana Edad , Mixoma/diagnósticoRESUMEN
BACKGROUND/AIM: Myxoma is the most common benign primary cardiac neoplasm, and usually originates from the left atrial septum. Early diagnosis of cardiac myxomas depends on a high index of a clinical suspicion. Surgical management must be done as soon as possible after diagnosis. The aim of this retrospective study was to present diagnostics and treatment outcome data of 61 patients with cardiac myxoma treated in the Military Medical Academy, Belgrade during a 49-years period. METHODS: Intra-hospital diagnosis was established in all the patients by the cardiologist. Diagnostic methods were various, in dependence on the examination period and suspected diagnosis. RESULTS: Within a 49-years period (1961-2009) heart myxoma was diagnozed and treated in 61 patients in the Military Medical Academy, Belgrade. Most of the operated patients were females (38 or 62.3%). The operated patients were 19-68 years old. Average age of all the patients was 47.9%. The great majority of them (98.4%) had atrial, and only one operated patient had ventricular myxoma. In 13 (21.3%) of the patients heart myxoma was found out accidentally due to no previous cardiologic symptomatology. In most patients (27.44%) symptomatology was presented as thromboembolic disease. Because of the suspected ventricular myxoma in one patient, the patient was operated on, but Hodgkin's lymphoma was found out which, according to the subsequent course of the disease, could be justifiably recognized as primary heart lymphoma. This study presented brief descriptions of the course of the disease in 4 patients with myxomas in each of the cardiac cavities. CONCLUSION: The only diagnostic difficulty in cardiac myxoma is due to its asymptomatic and oligosymptomatic presence within the longer period of time, namely, its growth period. Echocardiography should be the standard method of cardiologic examination of these patients, which could considerably contribute to early diagnosis and treatment of heart myxoma. Surgical extirpation of myxoma is the only and very successful therapeutic method.
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Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico , Adulto , Anciano , Femenino , Neoplasias Cardíacas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Mixoma/cirugía , Adulto JovenRESUMEN
INTRODUCTION: Secondary or metastatic tumors in the heart occur more frequently than primary ones, and, according to the published series, their frequency found in autopsic material ranges from 1.6% to 20.6%. Metastatic tumors in the heart are rarely clinically symptomatic, and, therefore, they are rarely diagnosed within the lifetime. They are mostly diagnosed at autopsy. The aim of this study was to analyze the frequency of metastatic tumors of the heart, their primary localization, as well as the localization of the metastases found in the autopsic material within the period 1972-2004. METHODS: During the autopsy of the patients died of metastatic tumors, we microscopically and macroscopically analyzed all the organs and tissues to determine the metastases of primary tumors in other organs, especially in the heart and pericardium. RESULTS: Within the period from 1972-2004, 11 403 autopsies were performed. In 2 928 (25.6%) out of 11 403 autopsies, the presence of malignant tumor was diagnosed, and in 79 (2.7%) of these cases, metastasis of the heart was found out. Only in 5 of the cases, the presence of metastasis in the heart was diagnosed during the lifetime. The most frequent metastases in the heart were caused by pulmonary carcinoma (18 cases), leukemia and malignant lymphoma (8 cases, each), then pancreatic and breast carcinoma, while the metastases of other carcinomas were rather rare. In 40 (60.76%) cases, the metastasis was localized in the myocardium, but more often in the left ventricle, in 24 (30.38%) cases in the pericardium, in 4 cases in the epicardium and in the 3 of them in the mitral and tricuspid valve. Only in one case of renal carcionoma, metastasis was found in the right atrium and it occurred by spreading (dissemination) through the lumen of the inferior vena cava. CONCLUSION: Metastatic tumors of the heart are rather rare, and rarely clinically symptomatic, and, thus, rarely diagnosed during life. The methods of choice for the diagnosis of the metastasis in the heart are echocardiography, computerized tomography, magnetic resonance imaging, cytological analysis of the pericardial effusion and biopsy. The treatment includes surgery, chemotherapy and radiotherapy.
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Neoplasias Cardíacas/secundario , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias Cardíacas/diagnóstico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
INTRODUCTION: Although Rudolf Virchow considered arteriosclerosis an inflammatory disease in his book Cellular Pathology publisched in 1858, the opinion that it was a degenerative arterial disease as a civilization disease prevailed. Nowadays, a great attention has been paid to the inflammatory process in the patogenesis of arteriosclerosis and particularly in the destabilization and rupture of plaque. AIM: To find out whether T and B lymphocytes, lipid macrophages, vascular smooth muscle and mast cells as well as plaque destabilization and rupture are present in ruptured arteriosclerotic plaque in the coronary arteries. METHODS: Histochemical and immunochemical analyses of 68 ruptured arteriosclerotic plaques from the coronary arteries were performed. Microscopic examination revealed the presence of inflammation elements in all of them. The following histochemical and immunochemical methods were applied: Masson's trichrome, actins, vimentin, CD3, CD43, CD68, CD20, CD45 and chlorine acetyl esterase. The control group included 10 arteriosclerotic plaques from the coronary arteries with fibrous cap, but without inflammation cells. RESULTS: Rupture of the arteriosclerotic plaque fibrous cap, with thinned and torn collagen fibers, was found in all of the 68 arteriosclerotic plaques. In 57 out of 68 analysed plaques, the increased number of T-lymphocytes, lipid macrophages, vascular smooth muscle and mast cells particularly on the plaque rupture site were found. In the remaining 11 specimens, mast cells were present in a somewhat smaller number. In the control group with the stable plaque, inflammation cells were not observed. CONCLUSION: Our results pointed out that the inflammatory elements, which might exert an effect upon the arteriosclerotic plaque destabilization, and rupture had been present in the ruptured arteriosclerotic plaque.
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Enfermedad de la Arteria Coronaria/patología , Vasos Coronarios/patología , Enfermedad de la Arteria Coronaria/metabolismo , Humanos , Inmunohistoquímica , Inflamación , Mediadores de Inflamación/análisis , Linfocitos/patologíaRESUMEN
INTRODUCTION: Arthritis in Reiter's syndrome (RS) is a reactive synovitis associated with a localized infection of the urogenital or gastrointestinal tract with a genetic predisposition. The pathogenetic mechanisms for synovitis in RS are still unknown. Our aim was to examine some of the pathogenetic mechanisms in Reiter's syndrome looking for morphologic changes, immunoprotein deposits and microorganism antigens in synovial biopsies and to determine whether synovial biopsy is useful in diagnosis of RS. MATERIAL AND METHODS: Thirty patients with urogenital form of RS were examined within a four-year period. Table 1 illustrates laboratory findings in our patients. We performed synovial biopsies looking for histopathological changes, deposits of immunoproteins and microorganism antigens. Analysis of synovial biopsy specimens was performed using light and immunofluorescence microscopy and fluorescein-labelled monoclonal antibodies to Chlamydia trachomatis. RESULTS: Histopathological examination of synovial membrane revealed marked proliferation of the synovial lining cells (SLC) with less or more abundant papillary projections, hypertrophic and edematous tissue with marked vascularisation in 28 (93.3%) cases. Fibrinoid necrosis foci were seen on the surface of synovial tissue. Chronic inflammatory cells (CIC) were diffusely distributed. Edema of the vessel walls, swollen endothelial cells, fibrinoid necrosis in vessel walls as well as multilaminated basement membranes were observed. All histopathologic changes are presented in Table 2. Immunofluorescent techniques in 12 out of 30 (40%) synovial membranes showed immunoglobulin deposits: IgG and IgA deposits were found in vessel walls in 7 cases each and IgM in 10 biopsy specimens. C3 was present perivascularly or within the vessel wall in 4 (13.3%) cases. Sections treated using fluorescein-conjugated antibody revealed Chlamydia in the synovial tissue in 2 patients. CONCLUSION: Biopsy specimens with previously described changes in patients with suspected Reiter's syndrome can be useful to confirm the diagnosis. According to our experience, multiple biopsies of abnormal synovia are recommended in these patients.
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Artritis Reactiva/diagnóstico , Biopsia , Membrana Sinovial/patología , Adolescente , Adulto , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Membrana Sinovial/químicaRESUMEN
AIM: To review ten-years experience in diagnostics and operative treatment of osteoid osteoma. METHODS: A total of 15 patients were retrospectively analyzed in this study. Clinical diagnosis was based on medical check-up, aspirin test, and conventional laboratory and radiographic examinations. CAT scan radionuclide bone scan, and magnetic resonance were performed in certain cases. All the patients were operatively treated by local resection of the tumor-infested bone. The resected part of the bone was intraoperatively checked by X-ray. The aim of this examination was to verify nidus in the resected bone. Afterwards, the resected bone with nidus was histologically analyzed. RESULTS: Osteoid osteoma was histologically verified in 86.6% of cases. Other forms of bone tumors were verified in 13.3%. In the early postoperative period patients were without previous discomforts. Future treatment consisted of regular medical check-up of all the patients. In order to verify the final results, in February 2002 another medical check-up was performed for 11 patients, upon their consent. All of the patients with verified osteoid osteoma were without discomforts. Medical findings were regular in each case. Conventional radiography showed a solid bone remodelling in place of resected bone. CONCLUSION: Osteoid osteoma is a benign bone tumor with typical clinical and radiographic findings. Operative treatment represents a method of choice and demands accurate preoperative localization of the lesion, with the help of computer-assisted tomography.
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Neoplasias Óseas/diagnóstico , Neoplasias Óseas/terapia , Osteoma Osteoide/diagnóstico , Osteoma Osteoide/cirugía , Adolescente , Adulto , Neoplasias Óseas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoma Osteoide/patologíaRESUMEN
Concentrations of carcinoembryonic antigen (CEA) and carborhydrate antigen (CA) 50 were measured in pleural effusion and sera of 57 patients with bronchogenic carcinoma and in 73 patients in whom the effusion was the sequela of tuberculous pleurisy. In the group with bronchogenic carcinomas, planocellular was confirmed in 19, microcellular in 17, macrocellular in 2, and adenocarcinoma in 18, while in 1 patient it was not possible to determine the histopathologic structure. The diagnosis of pleural disease was established upon the cytologic examination of the effusion and histopathologic examination of the pleural sample obtained by blind percutaneous needle biopsy or following pleuroscopy. CEA concentration in the sera of patients with bronchogenic carcinoma was significantly higher than in the patients with tuberculosis (p < 0.001), with sensitivity of 44% and ideal specificity and positive predictive value of 100%. In the same group highly significant difference of mean values of CEA concentrations in pleural effusion (p < 0.001), was also found with sensitivity of 60%, significant specificity of 99% and positive predictive value of 97%. CA 50 concentrations in the sera of patients with lung carcinoma were significantly higher than those in the sera of patients with tuberculous pleurisy (p < 0.05), and the sensitivity was 50%, while the specificity was 94% and positive predictive value was 75%. Significantly higher was also the value in the pleural effusion (p < 0.05), but the sensitivity was slightly lower--40%, but specificity was favorable as well as the positive predictive value (94 and 86%, respectively). The results indicate the significance of the determination of CEA and CA 50 in the sera and pleural effusion in the differentiation of malignant from tuberculous pleural effusion.
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Antígenos de Carbohidratos Asociados a Tumores/análisis , Antígeno Carcinoembrionario/análisis , Carcinoma Broncogénico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Derrame Pleural/química , Tuberculosis Pulmonar/diagnóstico , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derrame Pleural Maligno/química , Valor Predictivo de las Pruebas , Sensibilidad y EspecificidadRESUMEN
The serum levels of prostate-specific antigen (PSA) represent a significant diagnostic and monitoring parameter of prostatic carcinoma (PC). The aim of the study was to establish correlation of serum PSA level in addition to grade, histological type, and clinical stage of PC in patients with normal or intermediary PSA serum level. In 37 untreated PC patients with preoperative serum PSA levels ranging between 0.1 and 9.6 ng/ml, paraffin-embedded tissue and serum samples were immunohistologically studied and immunoassay for PSA was done. The most representative was poorly differentiated PC with D stage. In serum samples from PC patients 27 (73.7%) normal (< or = 4.0 ng/ml), and 10 (27.3%) intermediate (4.1-10 ng/ml) PSA levels were found. Immunohistochemistry, in 36 PC (97.3%) had demonstrated the expression of PSA. Our study results had shown low serum PSA levels in some patients with advanced poorly differentiated PC.
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Carcinoma/patología , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/patología , Carcinoma/diagnóstico , Humanos , Masculino , Neoplasias de la Próstata/diagnósticoRESUMEN
BACKGROUND: Patients with implanted aortic coronary grafts have different survival time, which raises the question why the efficacy of graft implants is so poor. The aim of this study was to present the results of the analysis of morphological changes in the vein grafts taken after the death of patients who died after surgery in different time intervals, as well to present the analysis of the grafts obtained after surgical reintervention. METHODS: The total number of 656 grafts of 308 dead patients was analyzed, as well as 76 grafts from 40 patients who underwent surgical reintervention. According to the duration of the graft since surgical intervention until death, all the analyzed changes were divided into two groups: a) early changes and complications, and b) late changes and complications in aorto-coronary vein grafts. RESULTS: After the autopsy, 518 vein grafts from the first group were evaluated histopathologically. Changes were found in the form of small or large areas with peeled endothelium in 266 grafts, with the insudation of fibrin and thrombocytes in such places, subendothelial edema, and occlusive thrombosis of the graft lumen. Significant stenosis, which occurred distally from the anastomoses, was present in 118 grafts without changes in the walls of the graft, and there was significant narrowing of the graft lumen in 134 vein grafts due to intimal hyperplasia. In the second group, 138 grafts were histopathologically analyzed after autopsy. Significant hyperplasia was present in 117 grafts with the migration of smooth muscle cells from media into intima, and in 21 grafts there were atheromatous plaques. In 120 veins analyzed before the graft implantation, the lesion or the lack of endothelium was found, as well as the penetration of fibrin and blood elements and intimal hyperplasia. In 46 veins analyzed before the graft implantation, significant intimal hyperplasia with the elevated number of smooth muscle cells was found. CONCLUSION: The most frequent lesions in the grafts were the lesions of the endothelium, which caused thrombosis formation and lumen occlusion. Intimal hyperplasia in patients with longer survival time occurred due to the migration of smooth muscle cells from the media, or due to the formation of atherosclerotic plaques, which caused graft lumen stenosis or thrombosis.
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Puente de Arteria Coronaria , Vena Safena/patología , Vena Safena/trasplante , Adulto , Anciano , Puente de Arteria Coronaria/mortalidad , Enfermedad Coronaria/patología , Enfermedad Coronaria/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Tasa de SupervivenciaRESUMEN
Ameloblastoma is a rare tumor of the jaw arising from odontogenic epithelium. There are sparse reports in the literature concerning cytologic features of this tumor. This paper presents two cases of ameloblastoma, diagnosed by imprint cytology and confirmed histopathologically. The imprints were hypercellular, with single cells and the groups of basaloid and polygonal squamous cells with huge vacuoles in cytoplasm. Stellate and fusiform cells were found in the background of the preparation. These morphologic parameters were sufficient for the cytologic diagnosis of ameloblastoma.
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Ameloblastoma/patología , Neoplasias Maxilomandibulares/patología , Ameloblastoma/diagnóstico , Citodiagnóstico , Diagnóstico Diferencial , Humanos , Neoplasias Maxilomandibulares/diagnóstico , MasculinoRESUMEN
We investigated clinical and morphological characteristics of replaced menisci after the transplantation of deep frozen meniscal allografts. We replaced medial menisci (in 18 New Zealand white rabbits) by meniscal grafts obtained from other rabbits. These grafts were kept in a deep freezer (3-5 weeks), thawed in sterile saline and transplanted. The menisci were removed and studied after 2 weeks (first group), 8 weeks (second group) and after 36 weeks (third group). Menisci from non-operated, contralateral knees served as controls. The tissue of the menisci investigated was processed using several histological and histochemical methods and analyzed by light microscope. Transplanted meniscal allografts retained a normal gross appearance, healed firmly through fibrovascular tissue to the recipient capsular tissue, and did not show macroscopic pathological changes. At the histological evaluation, in the first group the collagen fibers were irregularly oriented, with a low cellular population. In the second group, blood vessels were present, cellular repopulation and immature collagen fibers being observed. The third group had a more mature collagen tissue, with a significant cell repopulation. Deep-frozen meniscal allografts showed significant collagen remodeling with cellular and vascular ingrowth from the surrounding synovia. This suggests that used allografts function normally and protect underlying cartilage (AU)
Investigamos las características clínicas y morfológicas de meniscos sustituidos después del trasplante de alo-transplantes de menisco congelados a bajas temperaturas. Sustituimos meniscos mediales (en 18 conejos blancos de raza neozelandesa) mediante trasplantes de menisco obtenidos de otros conejos. Estas piezas se mantuvieron en un congelador (3-5 semanas), descongelados en solución salina estéril, y trasplantados. Los meniscos fueron retirados y estudiados después de dos semanas (grupo 1), 8 semanas (grupo 2) y después de 36 semanas (grupo 3). Los meniscos de rodillas contralaterales no operadas sirvieron como controles. El tejido de los meniscos estudiados fue procesado utilizando distintos métodos histológicos e histoquímicos y fueron analizados con microscopía óptica. Los alotrasplantes de menisco trasplantados mantuvieron una apariencia macroscópica normal; curaron firmemente mediante tejido fibrovascular adherido al tejido capsular del receptor, y no mostraron cambios patológicos macroscópicos. En la evaluación histológica, en el primer grupo las fibras de colágeno estaban orientadas de una manera irregular, con una población celular reducida. En el segundo grupo, estaban presentes vasos sanguíneos, observándose una repoblación celular junto con fibras de colágeno inmaduras. El tercer grupo tenía un tejido de colágeno más maduro, con una repoblación celular significativa. Los alotrasplantes de menisco congelados a bajas temperaturas mostraron un grado significativo de remodelación de colágeno, acompañado de un crecimiento hacia el interior de células y vasos a partir de la sinovial circundante. Esto sugiere que los alotransplantes usados funcionan de manera normal y que protegen el cartílago subyacente (AU)