RESUMO
OBJECTIVE: Our goal was to determine the difference in iron distribution between transfusion dependent (TD) and nontransfusion dependent (NT) patients with sickle cell disease (SCD). MATERIALS AND METHODS: The T2-weighted and T2*-weighted abdominal MR images in nine cases of homozygous SCD were reviewed to determine the distribution of low signal from iron in five TD and four NT patients. RESULTS: All eight patients with visualized spleens had decreased splenic signal intensity. One patient who had no history of splenectomy had no visualized splenic tissue. The majority of both groups had renal cortex of low signal intensity that was attributable to iron deposition from intravascular hemolysis and was not correlated with clinical renal abnormalities. None of the NT group had liver or pancreas of low signal intensity, while all five TD patients had decreased liver signal intensity and three of five had decreased pancreatic signal intensity. CONCLUSION: Decreased pancreatic signal intensity can occur in TD patients, perhaps suggesting total body iron overload. Nontransfusion dependent sickle cell patients usually have normal hepatic signal intensity and do not have total body iron overload, even in the presence of renal and splenic iron deposition.
Assuntos
Abdome/patologia , Anemia Falciforme/patologia , Transfusão de Sangue , Ferro/análise , Adolescente , Adulto , Anemia Falciforme/metabolismo , Anemia Falciforme/terapia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Distribuição TecidualRESUMO
OBJECTIVE: One of the indications for the rapidly expanding use of thoracoscopic surgery as an alternative to thoracotomy is the excision of peripheral lung nodules. Nodules judged too small or too far from the pleural surface to be seen or palpated during thoracoscopy must be localized beforehand. The purpose of this study was to evaluate the feasibility and effectiveness of percutaneous placement of spring hookwires to localize such nodules before video-assisted thoracoscopy. SUBJECTS AND METHODS: Under CT guidance, 17 nodules in 14 patients were preoperatively localized with the Kopans breast lesion localization system. Three patients who had solitary nodules had thoracoscopic resections for diagnosis because a previous transthoracic needle or transbronchial biopsy had been unsuccessful. Four patients who had lesions less than 8 mm in diameter had thoracoscopic biopsies because transthoracic fine-needle aspiration biopsy was not likely to be diagnostic. Seven patients, who had a total of 10 nodules, had therapeutic wedge resections of either limited metastases or a second bronchogenic carcinoma. Mean nodule diameter was 10 mm (range, 3-20 mm). The mean distance from nodule to costal pleura was 9 mm (range, 0-25 mm). At the end of the procedure, wire placement was confirmed by CT scanning. After thoracoscopy, the surgeons were questioned about the stability and utility of each hookwire localization. RESULTS: In all 17 procedures, a hookwire was placed successfully. In one case, the wire dislodged before thoracoscopy (after a 6-hr preoperative delay and severe bending of the wire during induction of anesthesia). In 16 of the 17 resections, the surgeon thought that thoracoscopic identification of the lesion would not have been possible without hookwire localization. Only one localization, across a major fissure, required placement of a second wire to localize a nodule. Wire-related complications included two instances of serious pain, five cases of clinically insignificant pneumothorax, and one large pneumothorax requiring drainage before a second nodule in the same lung was localized. CT scanning showed presumed local pulmonary hemorrhage in six cases without hemoptysis or hemothorax. CONCLUSION: CT-guided hookwire localization is easily and safely performed and permits thoracoscopic resection of lung nodules, which might otherwise be impossible.
Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Toracoscopia/métodos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma Broncogênico/diagnóstico por imagem , Carcinoma Broncogênico/secundário , Carcinoma Broncogênico/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Toracoscopia/efeitos adversosRESUMO
Magnetic resonance (MR) imaging was performed in 14 patients with biopsy-proved polycythemia vera (n = 4) or myelofibrosis (n = 10) to determine whether MR imaging findings can be correlated with the clinicopathologic diagnosis and established clinical parameters of severity (serum lactate dehydrogenase [LDH] and cholesterol levels) and chronicity (spleen size). Evaluation of marrow in the proximal femurs showed that patients could be categorized into three distinct groups based on anatomic patterns of normal fatty and abnormal low-signal-intensity (non-fatty) marrow in the femoral capital epiphysis (FCE) and greater trochanter (GT). Patients with nonfatty marrow in both the FCE and GT (n = 8) had significantly higher serum LDH (P less than .02) and lower serum cholesterol (P less than .02) levels than patients with fatty marrow in at least the GT (n = 6). Splenic volume, as measured from MR images, was significantly greater in the myelofibrosis group than in the polycythemia vera group (P less than .001). MR imaging provided a better understanding of these hematologic disorders and novel parameters for classification that are different from conventional histologic and laboratory data.
Assuntos
Medula Óssea/patologia , Imageamento por Ressonância Magnética , Policitemia Vera/patologia , Mielofibrose Primária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Colesterol/sangue , Feminino , Fêmur/patologia , Humanos , L-Lactato Desidrogenase/sangue , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Policitemia Vera/sangue , Mielofibrose Primária/sangue , Estudos Retrospectivos , Esplenomegalia/patologiaRESUMO
Parenchymal iron deposition occurs in hemochromatosis, while iron is deposited in reticuloendothelial (RE) cells after blood transfusions or rhabdomyolysis. Magnetic resonance images of patients with decreased liver signal intensity on T2-weighted images at 1.5 T were blindly compared in an effort to distinguish these conditions. In each of five patients with hemochromatosis, the pancreas had low signal intensity, but splenic signal intensity was decreased in only one. In contrast, only three of the 16 patients with RE iron overload had low pancreatic signal intensity, while all of these patients either had low splenic signal intensity (n = 14) or previously underwent splenectomy (n = 2). Distinction among these causes of iron deposition is clinically important because parenchymal iron overload from hemochromatosis may produce significant tissue damage, while the RE iron of transfusions and rhabdomyolysis is of little clinical consequence.
Assuntos
Ferro/metabolismo , Células de Kupffer/metabolismo , Fígado/patologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Biópsia , Feminino , Hemocromatose/diagnóstico , Hemocromatose/etiologia , Hemocromatose/metabolismo , Humanos , Células de Kupffer/patologia , Fígado/metabolismo , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Pâncreas/metabolismo , Pâncreas/patologia , Estudos Retrospectivos , Baço/patologia , Reação TransfusionalAssuntos
Esôfago/cirurgia , Pneumonectomia , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia Torácica , Adolescente , Adulto , Idoso , Criança , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonectomia/efeitos adversos , Pneumonectomia/métodos , Complicações Pós-Operatórias/etiologia , Cirurgia TorácicaRESUMO
Pulmonary edema was produced in nine mongrel dogs by: (a) saline lavage; (b) intravenous injection of oleic acid; and (c) intravenous injection of propranolol followed by ureteral ligation. The resulting effect could be characterized by varying the protein concentration in the pulmonary edema fluid. After induction, all dogs were killed and 20 samples from each passively deflated lung were obtained. Proton T1 and T2 values were measured on a Praxis II NMR spectrometer operated at 10.7 MHz and 37 degrees C. The water content of all samples was determined gravimetrically. Correlation between T1 or T2 measured in vitro and the ratio of wet to dry weight was highly significant (r greater than 0.95, P less than 0.001) in each pathological state. Regression curves indicate that although all three types of pulmonary edema can be characterized by slightly different slopes, the differences are statistically insignificant. Moreover, the slopes of previous studies, when recast in the same format, are very similar to our findings despite the use of different magnetic field strengths and different animal models. This study indicates that quantitation of pulmonary edema is possible, but in vitro measurements do not give useful information for characterizing the etiology of pulmonary edema.