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1.
Clin Case Rep ; 11(5): e7182, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37180317

RESUMEN

Sarcomatoid sweat gland carcinomas are rare among cutaneous cancers, with less than 20 cases described. A 54-year-old woman with sarcomatoid sweat gland carcinoma of the right upper extremity suffered extensive recurrence at 15 months, unresponsive to chemotherapy. There is no standard treatment or chemotherapy regimens for metastatic sweat gland carcinoma.

2.
Zhonghua Bing Li Xue Za Zhi ; 49(2): 122-128, 2020 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-32074723

RESUMEN

Objective: To investigate the clinicopathological and radiological features of benign fibro-osseous lesion (BFOL). Methods: Sixty-five cases of craniofacial BFOL, eight cases of peripheral ossifying fibroma (POF) and one case of low-grade central osteosarcoma diagnosed at Sichuan Provincial People's Hospital between January 2010 and March 2019 were collected. The clinicopathologic features, hematoxylin-eosin and immunohistochemical (IHC) staining and radiographic features were analyzed. MDM2 gene amplification was detected by FISH in difficult borderline cases. Results: This cohort of BFOLs included 50 cases of fibrous dysplasia (FD), 12 cases of ossifying fibroma (OF), and three cases of juvenile psammomatoid ossifying fibroma (JPOF). The average ages of patients with FD,OF and JPOF were 31.7, 39.2 and 26.0 years respectively. The male to female ratio was 1.0∶1.8.The average age of POF was 47.0 years, with male to female ratio of 1∶7. Patient of low-grade central osteosarcoma was a 48-year-old man. Twenty-seven cases of FD were located in the jaw, and 23 cases were in other craniofacial bones. Nine cases of OF were located in the jaw, and three cases were in the nasal cavity. Two cases of JPOF were in the nasal sinus, and one was in the jaw. All POF were located in the gingiva, and low-grade central osteosarcoma was located in the mandible. The imaging features of FD were luffa-like or ground-glass like signal shadows with poorly defined borders with expansion. OF had clear borders or sclerosing margins. Both JOF and low-grade central osteosarcoma were expansile intraosseously and with focally invasive nodular masses with ground-glass like signal shadows; and POF showed soft tissue mass with bone formation. Histological features of BFOLs showed mixed fibrous and irregular osteoid lesions. FD had no clear relationship with the host bone and no osteoblasts surrounded the bone trabeculae. Osteoblasts rimming was found in OF, and the boundaries of the host bone were clear. JPOF and low-grade central osteosarcoma infiltrated the host bone focally, and the latter showed mild cellular atypia. MDM2 amplification was detected in low-grade central osteosarcoma. Conclusions: BFOLs are a group of fibro-osseous lesions with similar morphology in the head and neck and face, but their clinical features and prognosis are different; and their imaging and histological characteristics are also slightly different. Attentions should be given to the combination of clinical, imaging and pathologic features of BFOLs, especially the differential diagnosis between BFOLs and low-grade central osteosarcoma. Molecular detection could be used to assist the diagnosis in difficult cases.


Asunto(s)
Neoplasias Óseas , Fibroma Osificante , Osteosarcoma , Huesos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía
3.
Anaesthesia ; 63(7): 705-13, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18582255

RESUMEN

Risk-stratification models based on pre-operative patient and disease characteristics are useful for providing individual patients with an insight into the potential risk of complications and mortality, for aiding the clinical decision for surgery vs non-surgical therapy, and for comparing the quality of care between different surgeons or hospitals. Our study aimed to apply artificial neural networks (ANN) models to predict mortality and morbidity after cardiac surgery, and also to compare the efficacy of this model to that of the logistic regression model and Parsonnet score. The accuracy of the ANN, logistic regression and Parsonnet score in predicting mortality was 83.8%, 87.9% and 78.4%. The accuracy of the ANN, logistic regression and Parsonnet score in predicting major morbidity was 79.0%, 74.3% and 68.6%. The area under the receiver operating characteristic curves (AUC) of the ANN, logistic regression and Parsonnet score in predicting in-hospital mortality were 0.873, 0.852 and 0.829. The AUCs of the ANN, logistic regression and Parsonnet score in predicting major morbidity were 0.852, 0.789 and 0.727. The results showed the ANN models have the best discriminating power in predicting in-hospital mortality and morbidity among these models.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Redes Neurales de la Computación , Adulto , Anciano , Métodos Epidemiológicos , Femenino , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
4.
Br J Anaesth ; 98(1): 60-5, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17065170

RESUMEN

BACKGROUND: Several medications have proved to be useful in preventing postoperative nausea and vomiting (PONV). However, routine antiemetic prophylaxis is not cost-effective. We evaluated the accuracy and discriminating power of an artificial neural network (ANN) to predict PONV. METHODS: We analysed data from 1086 in-patients who underwent various surgical procedures under general anaesthesia without antiemetic prophylaxis. Predictors used for ANN training were selected by computing the value of chi(2) statistic and information gain with respect to PONV. The configuration of the ANN was chosen by using a software tool. Then the training of the ANN was performed based on data from a training set (n=656). Testing validation was performed with the remaining patients (n=430) whose outcome regarding PONV was unknown to the ANN. Area under the receiver operating characteristic (ROC) curves were used to quantify predictive performance. ANN performance was compared with those of the Naïve Bayesian classifier model, logistic regression model, simplified Apfel score and Koivuranta score. RESULTS: ANN accuracy was 83.3%, sensitivity 77.9% and specificity 85.0% in predicting PONV. The areas under the ROC curve follow: ANN, 0.814 (0.774-0.850); Naïve Bayesian classifier, 0.570 (0.522-0.617); logistic regression, 0.669 (0.623-0.714); Koivuranta score, 0.626 (0.578-0.672); simplified Apfel score, 0.624 (0.576-0.670). ANN discriminatory power was superior to those of the other predicting models (P<0.05). CONCLUSIONS: The ANN provided the best predictive performance among all tested models.


Asunto(s)
Redes Neurales de la Computación , Náusea y Vómito Posoperatorios/etiología , Adulto , Anestesia General , Antieméticos/administración & dosificación , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Náusea y Vómito Posoperatorios/prevención & control
5.
Cutis ; 64(2): 135-6, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10467510

RESUMEN

Lichen nitidus is a rare condition of unknown cause, characterized by minute, flesh-colored, shiny papules occurring on the genitalia, abdomen, chest, and extremities. This disorder is most often localized, but a few cases of generalized lichen nitidus have been reported. We describe a young patient with a 1.5-year history of unremitting generalized lichen nitidus.


Asunto(s)
Liquen Nítido/diagnóstico , Niño , Diagnóstico Diferencial , Femenino , Humanos , Liquen Nítido/patología
6.
Arch Pathol Lab Med ; 123(9): 835-7, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10458835

RESUMEN

We report a case of coinfection of visceral leishmaniasis and Mycobacterium avium-intracellulare in the same lesions in the small bowel and bone marrow of a 33-year-old man with acquired immunodeficiency syndrome who complained of abdominal pain and chronic diarrhea. The duodenal mucosa and bone marrow biopsy specimens showed numerous foamy macrophages packed with two forms of microorganisms that were identified histologically and ultrastructurally as Leishmania and Mycobacterium species. Visceral leishmaniasis is rarely suspected in patients residing in nonendemic countries including the United States. It should be included in the differential diagnosis for opportunistic infection in patients with acquired immunodeficiency syndrome. An appropriate travel history is important. To our knowledge, this is the first reported case showing coinfection of visceral leishmaniasis and Mycobacterium avium-intracelluulare in the same lesion in a patient with acquired immunodeficiency syndrome.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Leishmaniasis Visceral/diagnóstico , Infección por Mycobacterium avium-intracellulare/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/parasitología , Adulto , Animales , Biopsia , Médula Ósea/microbiología , Médula Ósea/parasitología , Médula Ósea/patología , Humanos , Mucosa Intestinal/microbiología , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Mucosa Intestinal/ultraestructura , Intestino Delgado/microbiología , Intestino Delgado/parasitología , Intestino Delgado/patología , Intestino Delgado/ultraestructura , Leishmaniasis Visceral/complicaciones , Leishmaniasis Visceral/patología , Macrófagos/microbiología , Macrófagos/parasitología , Macrófagos/ultraestructura , Masculino , Microscopía Electrónica , Infección por Mycobacterium avium-intracellulare/complicaciones , Infección por Mycobacterium avium-intracellulare/patología
7.
Arch Pathol Lab Med ; 123(9): 842-5, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10458837

RESUMEN

The interstitial cells of Cajal complex within the gut wall function as a pacemaker to direct peristalsis. Their neoplastic counterpart is the gastrointestinal pacemaker cell tumor, a spindle and/or epithelioid cell mesenchymal tumor previously known as gastrointestinal stromal tumor or incorrectly called leiomyosarcoma in some cases of older reports. Although numerous cases of gastrointestinal leiomyosarcomas have been documented in the English-language literature, no pediatric case of gastrointestinal stromal tumor or gastrointestinal pacemaker cell tumor has, to our knowledge, been recorded. Herein, we report a case of congenital gastrointestinal pacemaker cell tumor confirmed by immunohistochemistry and electron microscopy in a full-term male newborn.


Asunto(s)
Relojes Biológicos , Neoplasias del Yeyuno/congénito , Neoplasias del Yeyuno/patología , Células del Estroma/patología , Biomarcadores de Tumor/metabolismo , Humanos , Inmunohistoquímica , Recién Nacido , Neoplasias del Yeyuno/metabolismo , Masculino , Microscopía Electrónica
8.
Sarcoma ; 3(2): 135-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-18521276

RESUMEN

Subject. A 27-year-old Hispanic male with clinical manifestation of neurofibromatosis type 1 developed chronic constipation and urination difficulty along with recently increased abdominal bloating and anorexia. He also noted 40 lbs weight loss over period of 1 year. Physical and radiographic examinations revealed a large mass in the right pelvic fossa.Results. The surgically removed tumor was demonstrated, histologically, immunohistochemically, and ultrastructurally, to be a malignant hemangiopericytoma.Discussion.Although non-neurogenic tumors associated with neurofibromatosis have been reported in these patients, only one hemangiopericytoma case has been found in the English literature. We report here another case of this rare malignant hemangiopericytoma in a patient with neurofibromatosis.

9.
J Pediatr Hematol Oncol ; 20(6): 567-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9856681

RESUMEN

PURPOSE: The authors introduced a successful trial of a chemotherapy regimen to treat refractory thrombocytopenia and pain caused by a rare kaposiform hemangioendothelioma that had been refractory to corticosteroids. PATIENT AND METHOD: A 6-year-old Latina girl with diffuse petechiae, constant pain and edema in her right lower extremity, and severe thrombocytopenia was brought for treatment. Physical examination revealed a large mass in the right lower extremity. The surgical specimen resected earlier in Mexico showed kaposiform hemangioendothelioma, an extremely rare vascular tumor that is frequently associated with consumptive coagulopathy and lymphangiomatosis. Corticosteroid therapy in Mexico had been ineffective in controlling the tumor size, pain, or thrombocytopenia. The patient was brought to the United States because of a rapidly enlarging tumor and intractable leg pain, causing inability to ambulate. Laboratory examinations revealed profound thrombocytopenia and evidence of consumptive coagulopathy. Because of the rapidly enlarging lesion, it was decided to give six cycles of a chemotherapy regimen consisting of vincristine, cyclophosphamide, and actinomycin D (VAC). RESULT: The patient responded to the first cycle of chemotherapy with partial reversal of the thrombocytopenia. The additional five cycles of the same chemotherapy regimen resulted in complete resolution of thrombocytopenia and significant improvement of the pain and edema in the right lower extremity. A follow-up imaging study 9 months later revealed a marked decrease in size of the vascular tumor. CONCLUSION: Inoperable kaposiform hemangioendothelioma unresponsive to corticosteroids can be successfully treated with chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hemangioendotelioma/tratamiento farmacológico , Niño , Ciclofosfamida/administración & dosificación , Dactinomicina/administración & dosificación , Femenino , Humanos , Sarcoma de Kaposi/etiología , Síndrome , Trombocitopenia/tratamiento farmacológico , Vincristina/administración & dosificación
10.
Arch Pathol Lab Med ; 122(1): 97-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9448027

RESUMEN

A cutaneous meningioma of the external auditory canal occurred in a 48-year-old Filipino woman who had undergone subtotal resection of a dural-based intracranial meningioma at the ipsilateral cerebellopontine angle 36 months previously. Radiologic findings demonstrated a recurrence of intracranial meningioma with surface erosion and heterogeneous densities of the mastoid bone, without extension to the area of the external auditory canal. Meningioma in the external ear canal is extremely rare. To our knowledge, there have been only two previously reported cases, both without intracranial lesion. In this case, the auditory canal lesion may represent either an ectopic meningioma arising from an arachnoid cell rest or an occult direct extension from intracranial menigioma.


Asunto(s)
Neoplasias Encefálicas/patología , Conducto Auditivo Externo , Meningioma/secundario , Neoplasias Primarias Desconocidas/patología , Neoplasias Cutáneas/secundario , Actinas/análisis , Neoplasias Encefálicas/química , Neoplasias Encefálicas/diagnóstico por imagen , Cromograninas/análisis , Femenino , Humanos , Inmunohistoquímica , Queratinas/análisis , Meningioma/química , Meningioma/patología , Persona de Mediana Edad , Mucina-1/análisis , Neoplasias Primarias Desconocidas/química , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patología , Sinaptofisina/análisis , Tomografía Computarizada por Rayos X
11.
Cutis ; 59(3): 111-2, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9071546

RESUMEN

Several benign and malignant lesions have occurred in tattoos, including verrucae, granulomas, allergic reactions, basal cell carcinomas, and squamous cell carcinomas. In addition, seven documented cases of malignant melanoma occurring in tattoos have been reported in the English literature. We describe another patient with malignant melanoma in a tattoo.


Asunto(s)
Melanoma/etiología , Neoplasias Cutáneas/etiología , Tatuaje/efectos adversos , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Neoplasias Cutáneas/patología
12.
Artery ; 22(2): 61-79, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8864249

RESUMEN

The effects of the cholesterol oxides on low density lipoprotein receptor (LDLR) gene expression were investigated. Cultured rabbit aortic smooth muscle cells were incubated with 1, 2, and 5 micrograms/ml culture medium concentrations of pure cholesterol, 25-hydroxycholesterol (25-OH), 7-ketocholesterol (7-keto), cholestane-3 beta, 5 alpha, 6 beta-triol (triol) and cholesterol-5 alpha, 6 alpha-epoxide (epoxide) for 12 hours and with vehicle only as control. Total mRNAs were extracted and electrophoresed. Northern blot hybridization analyses were performed. The results showed mRNA expressions of LDLR gene were inhibited to 16.1 +/- 4.4%, 33.8 +/- 0.6%, 42.8 +/- 1.8% and 46.9 +/- 3.9% of control by 25-OH, 7-keto, epoxide and triol respectively. Pure cholesterol showed only minimal inhibition. The inhibitions were time dependent. Although cholesterol oxides have been shown to alter many membrane-related functions and the LDLR domain are located in the cell membrane. The findings of this study suggested that the cholesterol oxides exerted their repressive actions on LDLR function primarily by down-regulating LDLR gene expression rather than directly upon cell membrane.


Asunto(s)
Colesterol/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hidroxicolesteroles/farmacología , Músculo Liso Vascular/metabolismo , Receptores de Lipoproteína/genética , Animales , Northern Blotting , Células Cultivadas , Colestanoles/farmacología , Colesterol/análogos & derivados , Cetocolesteroles/farmacología , ARN Mensajero/análisis , Conejos , Receptores de Lipoproteína/metabolismo
13.
J Am Soc Echocardiogr ; 8(6): 947-52, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8611300

RESUMEN

This case reports coccidiomycosis presenting as pericarditis with tamponade rapidly progressing to effusive-constrictive pericarditis and death over 72 hours. Coccidiomycosis pericarditis is a rapidly progressing disease requiring early and complete pericardiectomy to avoid the hemodynamics of constriction. We illustrate the use of echocardiography in this case and demonstrate the histopathology. We review the literature and discuss therapy and management. Coccidiomycosis is often clinically unsuspected and unrecognized by the health care worker unfamiliar with the disease process.


Asunto(s)
Coccidioidomicosis/complicaciones , Derrame Pericárdico/etiología , Pericarditis Constrictiva/etiología , Adulto , Coccidioidomicosis/patología , Progresión de la Enfermedad , Ecocardiografía , Humanos , Masculino , Derrame Pericárdico/diagnóstico por imagen , Derrame Pericárdico/patología , Pericarditis Constrictiva/diagnóstico por imagen , Pericarditis Constrictiva/patología
15.
Cardiovasc Surg ; 3(5): 479-84, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8574529

RESUMEN

Polytetrafluoroethylene (PTFE) prostheses were modified to produce two types of composite porosity PTFE grafts: type I--inner 60 microns/outer 20 microns and type II--inner 20 microns/outer 60 microns. These composite porosity PTFE designs were investigated for bleed through, graft healing and patency and compared with high porosity PTFE (60 microns) and standard PTFE (20 microns) grafts. The grafts were implanted into the carotid and femoral arteries of dogs and retrieved after 4, 12 and 18 weeks. Both composite porosity grafts showed significantly less bleed through than standard and high porosity grafts after reperfusion. In composite grafts, the 60-microns layer allowed fibrovascular tissue and histiocyte ingrowth from perigraft tissue, but the 20-microns layer did not. Neointima formation occurred earlier and endothelialization was more extensive in high porosity grafts, but seroma formation occurred in 25% of cases. In type I composite porosity grafts, smooth muscle cells of neointima migrated into the pores of the graft, providing a firmly anchored intima. Type II composite porosity grafts allowed better ingrowth of fibrovascular tissue at the outer layer from the perigraft tissue; however, endothelialization was not completed. Composite porosity grafts should be considered for evaluation in specific clinical situations.


Asunto(s)
Prótesis Vascular , Animales , Arterias Carótidas/patología , Arterias Carótidas/cirugía , Arterias Carótidas/ultraestructura , División Celular , Perros , Femenino , Arteria Femoral/patología , Arteria Femoral/cirugía , Arteria Femoral/ultraestructura , Oclusión de Injerto Vascular/patología , Microscopía Electrónica de Rastreo , Permeabilidad , Politetrafluoroetileno , Porosidad , Túnica Íntima/patología , Túnica Íntima/ultraestructura
16.
Am J Card Imaging ; 9(3): 167-73, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7549356

RESUMEN

Precipitates of calcium phosphate in coronary arteries always indicate the presence of atherosclerosis. The mass of these precipitates is related to the severity of atherosclerosis. To determine the accuracy of electron beam computed tomographic (CT) mass estimates, we imaged 21 human hearts inside an anthropomorphic chest phantom using an Imatron C-100 electron beam CT scanner (Imatron, San Francisco, CA). We then incinerated the 63 imaged coronary arteries and weighed the mineral ash. We calculated the mass estimates from the images using an algorithm derived from a model that assumes simple radiographic properties of the coronary arteries. We also calculated the currently used coronary calcium score for each artery. Although both the mass estimates and the scores correlated with the actual mass of the incinerated specimens (r = .97 and r = .93), the correlation with the mass estimates was better (P = .02; William's test). The regression equation relating the actual mass to the mass estimates was y = 1.37 x + 14, indicating that the CT mass estimates consistently underestimate actual coronary calcium phosphate mass. We conclude that relative mass estimates using electron beam CT scanning are accurate and that both these and the currently employed calcium scores reflect the actual mass of precipitated calcium phosphate in diseased coronary arteries.


Asunto(s)
Fosfatos de Calcio/análisis , Vasos Coronarios/química , Tomografía Computarizada por Rayos X , Algoritmos , Calcio/análisis , Precipitación Química , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/metabolismo , Durapatita/análisis , Electrones , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Estructurales , Análisis de Regresión , Tomógrafos Computarizados por Rayos X
17.
J Invest Surg ; 7(2): 143-50, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8049177

RESUMEN

A canine model was developed to induce eccentric iliac artery stenosis. Lesions were induced by exposing the medial aspect of the right and left common iliac arteries in four animals to direct argon laser energy (LA). A 2.5-mm diameter side-firing laser probe was used to deliver 10 W of power in 5-s intervals. Twenty-five pulses were delivered over a 5-cm length of artery with an approximate spot size of 0.8 mm2. Selected arteries (n = 2, LA + Ca) were injected in the same laser injury site with calcium chloride (10% solution). Injections were accurately accomplished using an angioscopically guided guidewire/needle device. In all cases, the internal elastic lamina was broken with focal disruptions of the media. At 9 and 14 days, the LA (n = 3) and LA + Ca vessels (n = 1) had minimal stenoses (< 5% area reduction). These vessels contained edematous media with replacement of necrotic smooth muscle by fibrous tissue. At 23 days, the LA (n = 1) and LA + Ca (n = 1) vessels contained 22% and 33% luminal reductions, respectively, with moderate neointimal proliferation and no evidence of calcification. At 56 days the LA vessels (n = 2) contained 30 and 42% luminal area stenoses with marked neointimal hyperplasia. This preliminary data suggests that controlled arterial wall injury with LA irradiation can induce eccentric fibrointimal lesions in a canine model.


Asunto(s)
Angioplastia , Arteriosclerosis/cirugía , Modelos Animales de Enfermedad , Arteria Ilíaca/cirugía , Animales , Perros , Arteria Ilíaca/patología , Arteria Ilíaca/efectos de la radiación , Rayos Láser
18.
Lasers Surg Med ; 15(3): 254-62, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7830470

RESUMEN

This canine study (n = 6) evaluated the acute and chronic effects of Nd:YAG laser prostatectomy using a Prolase II fiber. The Prolase II device consists of a 1,000 microns quartz fiber which directs a cone of Nd:YAG laser energy, at 45 degrees to the axis of the fiber, into the prostatic urethra under direct visual guidance [visual laser ablation of prostate, (VLAP)]. Under visual guidance and saline irrigation, 60 seconds of 60 watts of laser power was delivered at 3, 6, 9, and 12 o'clock positions (14,400 J). One canine was instrumented but received no laser energy (control). One prostate was harvested acutely. The remaining four laser-treated dogs were evaluated at 6 to 16 weeks. The histopathology of acute laser effects shows areas of necrosis with loss of glandular structures and stromal edema. Surrounding this area was a zone of degenerative glandular structures extending up to 12.6 mm into the prostate. Two of the four dogs developed urinary retention at 6.5 and 9 weeks. On examination, both were found to have fibrotic strictures at the distal prostatic urethra with markedly dilated proximal prostatic urethral lumens (1.98 and 2.8 cm). Two other dogs showed no signs of urinary retention at sacrifice. Histopathology, both the 6 and 16 week laser-treated animals without urinary retention demonstrated dilated prostatic urethras with maximum cross-sectional diameters of 1.52 and 1.50 cm, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Terapia por Láser/instrumentación , Prostatectomía/instrumentación , Animales , Perros , Estudios de Evaluación como Asunto , Tecnología de Fibra Óptica/instrumentación , Terapia por Láser/métodos , Masculino , Complicaciones Posoperatorias/etiología , Próstata/patología , Estrechez Uretral/etiología , Retención Urinaria/etiología
19.
Lasers Surg Med ; 14(2): 111-7, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8183045

RESUMEN

This preliminary report describes formation of femoral arterio-venous fistulas (n = 10) in six dogs using a 1.32-microns wavelength Nd:YAG laser welding technique. Stay sutures (6-0 polypropylene) were placed at 5-7 mm intervals along the anastomoses for vessel apposition. Delivery of laser energy through a 400-microns diameter fiber optic was controlled by a new computer-based software system. At 3 mm distance above the anastomosis, energy fluences of 110-260 J/mm2/cm length of anastomosis were used for laser welding. One or two additional hemostatic sutures were required in seven of the ten anastomoses. Flow was maintained for 1-2 hours prior to tissue harvesting. No thrombosis or delayed anastomotic failures were observed after initial welding and repair. Histologic examination revealed good apposition and adherence between wall layers and a fibrinous coagulum at the intimal junctions. Mild thermal injury of the wall was present at some anastomoses. This early investigation suggests that a 1.32 microns Nd:YAG laser welding technique can successfully create large vessel arteriovenous fistulas in the canine.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/métodos , Arteria Femoral/cirugía , Vena Femoral/cirugía , Terapia por Láser/métodos , Animales , Perros , Terapia por Láser/instrumentación , Programas Informáticos , Suturas
20.
J Invest Surg ; 6(6): 509-18, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8123612

RESUMEN

Standard polytetrafluoroethylene (PTFE) grafts (30-microns internodal distance, ID) (ST grafts), high-porosity PTFE grafts (90 microns ID) (HP grafts), high-porosity PTFE grafts preclotted with autogenous blood (BHP grafts), and high-porosity PTFE grafts presealed with fibrin glue (FHP grafts) were implanted in both common carotid and femoral arteries of 18 dogs. Of the three high-porosity groups, the FHP graft showed the shortest bleeding time. Seromas and/or hematomas occurred as follows: ST grafts 1, HP grafts 7 (P < .05 vs ST), BHP grafts 5 and 2 with FHP grafts. Fibrin glue was observed in all histological sections of 1-week samples, but by 4 weeks it was almost totally absorbed. No endothelialization (ET) was measurable at 2 weeks. By 4 weeks ET extended for a short distance from each anastomosis and there were no significant differences between the four graft groups. At 18 weeks, the HP, BHP, and FHP grafts showed a significant increase in ET compared with the ST graft (P < .01) but there were no significant differences between the three types of high-porosity graft. The differences in patency rates and neointimal thicknesses did not reach statistical significance. High-porosity PTFE grafts showed superior endothelialization in dogs; however, the enlarged ID of PTFE grafts increased intraoperative bleeding and postoperative seroma formation. Fibrin glue sealant controlled bleeding through the graft wall without affecting graft healing, but its sealant effect was not enough to prevent late fluid leakage.


Asunto(s)
Prótesis Vascular , Endotelio Vascular/fisiología , Politetrafluoroetileno , Animales , Perros , Endotelio Vascular/ultraestructura , Femenino , Adhesivo de Tejido de Fibrina
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