RESUMEN
BACKGROUND: Electrical impedance scanning (EIS) identifies tissue impedance changes associated with malignancy. Methods to distinguish benign from malignant thyroid nodules, particularly in patients with indeterminate cytology are lacking. PURPOSE: To determine the diagnostic accuracy of EIS in the preoperative evaluation of thyroid nodules. PATIENTS AND METHODS: From September 2002 to December 2006, 216 patients underwent thyroid fine needle aspiration (FNA) and EIS prethyroidectomy in this prospective cohort study. EIS, either positive or negative for malignancy, was correlated with final histopathology. A focal bright spot over a thyroid nodule correlating with increased conductivity and/or capacitance >25% baseline sternocleidomastoid muscle impedance defined positive EIS. Study endpoints were EIS accuracy, sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV). This study has been registered in the National Institutes of Health's public trials registry at ClinicalTrials.gov. The registration number is NCT00571077. RESULTS: EIS correctly diagnosed 96 of 110 patients with malignant and 75 of 106 patients with benign dominant thyroid nodules: Sn = 87%, Sp = 71%, PPV = 76%, NPV = 84%: overall EIS accuracy = 79%. Pretest cancer probability of 51% (110 of 216) increased to 76% (96 of 127) post-EIS, and preoperative use of EIS would result in a significant reduction (71%, 75 of 106) in number of operations performed for benign nodules. EIS performance was similar for 109 patients with indeterminate FNA: Sn = 83%, Sp = 67%, PPV = 61%, NPV = 87%, accuracy = 73%. Pretest probability of cancer increased from 39% (42 of 109) to 61% (35 of 57) post-EIS. The use of EIS would result in a significant reduction (67%, 45 of 67) in the number of purely diagnostic thyroidectomy for indeterminate FNA. CONCLUSION: EIS shows promise in differentiating thyroid nodules. Further EIS hardware and software optimization is warranted to improve upon the already favorable negative predictive value in indeterminate thyroid nodules.
Asunto(s)
Carcinoma/diagnóstico , Electrodiagnóstico , Nódulo Tiroideo/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/fisiopatología , Carcinoma/cirugía , Estudios de Cohortes , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Nódulo Tiroideo/fisiopatología , Nódulo Tiroideo/cirugía , TiroidectomíaRESUMEN
BACKGROUND: Electrical impedance scanning (EIS) measures changes in breast tissue associated with breast cancer (Br-Ca) development. The T-Scan(tm2000 (ED is designed to use EIS to identify women ages 30-39 with elevated risk of breast cancer (i.e., T-Scan+ women). AIM: To estimate the relative probability of breast cancer in a T-Scan+ woman compared to a randomly selected young woman. METHODS: A prospective, two-cohort trial was conducted in pre-menopausal women. The Specificity (S(p))-Cohort evaluated T-Scan specificity in 1,751 asymptomatic women ages 30-39. The Sensitivity)S(n))-Cohort evaluated T-Scan sensitivity in 390 women ages 45-30 scheduled for biopsy. Specificity, sensitivity, and conservative estimate of disease prevalence were used to calculate relative probability. RESULTS: In the S(p)-Cohort, 93 of 1,751 women were T-Scan+ (S(p) = 94.7%; 95% CI: 93.7-95.7%). In the S(n)-Cohort, 23 of 87 biopsy-proven cancers were T-Scan+ (S(n) = 26.4%; 95% CI: 17.4-35.4%). Given S(p) = 94.7%, S(n) = 26.4% and prevalence of 1.5 cancers/1,000 women (ages 30-39), the relative probability of a T-Scan+ woman having Br-Ca is 4.95: (95% CI: 3.16-7.14). CONCLUSION: EIS can identify a subset of young women with a relative probability of breast cancer almost five times greater than in the population of young women at-large. T-Scan+ women have a sufficiently high risk of Br-Ca to warrant further surveillance or imaging.
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Neoplasias de la Mama/diagnóstico , Mama/patología , Impedancia Eléctrica , Adulto , Biopsia , Estudios de Cohortes , Electrodiagnóstico/instrumentación , Electrodiagnóstico/métodos , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Premenopausia/fisiología , Probabilidad , Estudios Prospectivos , Medición de Riesgo , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Electrical impedance scanning (EIS) is a novel imaging technique based on differential electrical conductivity and capacitance of malignant and normal human tissues. The aim of this study was to evaluate the accuracy of EIS in the detection of thyroid malignancies. METHODS: Patients with thyroid nodules scheduled for thyroid surgery were eligible for the study. Enrolled patients underwent EIS with a T-Scan 2000ED. Nodule location, size, and type (cystic vs. solid) measured by ultrasound, cytology results, thyroid conductivity, and capacitance calculated by EIS were recorded. EIS results were interpreted as positive or negative for malignancy and compared with final histopathology results. Study end points included EIS accuracy, sensitivity, specificity, negative and positive predictive values, and false-positive and false-negative rates. RESULTS: Sixty-four patients were enrolled onto the study, and all underwent either lobectomy-isthmusectomy (20%) or total thyroidectomy (80%). The mean tumor diameter was 2.64 +/- 14.8 mm. Thyroid cancers were identified by histology in 30 patients (46.9%). There were 11 false-positive and four false-negative cases. The overall diagnostic accuracy of EIS was 76.6% (49 of 64 correct diagnoses). The sensitivity and specificity of EIS were 86.7% (26 of 30 true positive) and 67.6% (23 of 34 true negative), respectively. The corresponding positive and negative predictive values were 70.3% and 85.2%. CONCLUSIONS: EIS is a potentially useful imaging modality for differentiating thyroid neoplasms. If these results are confirmed in large-scale trials, EIS may be an important part of the evaluation of thyroid nodules.
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Impedancia Eléctrica , Neoplasias de la Tiroides/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Composición Corporal , Diagnóstico por Imagen/métodos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Prospectivos , Neoplasias de la Tiroides/cirugía , Nódulo Tiroideo/diagnóstico , TiroidectomíaRESUMEN
PURPOSE: To evaluate a system for computer-aided classification (CAC) of lesions assigned to Breast Imaging Reporting and Data System (BI-RADS) category 3 at conventional mammographic interpretation. MATERIALS AND METHODS: A CAC system was used to analyze 106 cases of lesions (42 malignant) that at blinded retrospective interpretation were assigned to BI-RADS category 3 by at least two of four radiologists. The CAC system automatically extracted from the digitized mammograms quantitative features that characterized the lesions. The system then used a classification scheme to score the lesions by the likelihood of their malignancy on the basis of these features. The classification scheme was trained with 646 pathologically proved cases (323 malignant), and the results were tested with receiver operating characteristic (ROC) analysis by using the jackknife method. Sensitivity, specificity, positive predictive value, and accuracy were calculated. Category 3 lesions were stratified among BI-RADS categories 2-5 according to CAC-assigned lesion score, and this classification was compared with the results of pathologic analysis. RESULTS: Jackknife analysis of CAC results in the training data set yielded a sensitivity of 94%, specificity of 78%, positive predictive value of 81%, and area under the ROC curve of 0.90. Of the 42 malignant lesions that had been classified at conventional interpretation as probably benign, nine were assigned by the CAC system to BI-RADS category 4, and 29 were assigned to category 5. The CAC system correctly upgraded the BI-RADS classification of these 38 lesions (sensitivity, 90%) and incorrectly upgraded the classification of only 20 benign lesions (specificity, 69%). CONCLUSION: The CAC system scored 38 of the 42 malignant lesions initially assigned to BI-RADS category 3 as BI-RADS category 4 or 5, and thus correctly upgraded the category in 90% of these lesions.
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Neoplasias de la Mama/clasificación , Diagnóstico por Computador , Mamografía , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Sistemas de Información Radiológica , Adulto , Anciano , Anciano de 80 o más Años , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Enfermedad Fibroquística de la Mama/clasificación , Enfermedad Fibroquística de la Mama/diagnóstico por imagen , Enfermedad Fibroquística de la Mama/patología , Humanos , Persona de Mediana Edad , Lesiones Precancerosas/clasificación , Lesiones Precancerosas/diagnóstico por imagen , Lesiones Precancerosas/patología , Valor Predictivo de las Pruebas , Probabilidad , Curva ROC , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
RATIONALE AND OBJECTIVES: The purpose of this study was to determine whether the size of mammographically detected microcalcifications is predictive of malignancy. MATERIALS AND METHODS: Two hundred sixty mammograms showing clustered microcalcifications with proven diagnoses (160 malignant, 100 benign) were respectively reviewed by experienced mammographers. Lesions that were obviously benign in appearance were excluded from the study. A computer-aided diagnosis system digitized the lesions at 600 dpi, and the microcalcifications on the digital image were interactively defined by mammographers. Subsequently, three quantitative features that reflected the size of the microcalcifications-length, area, and brightness-were automatically extracted by the system. For each feature, the standard average of values obtained for individual calcifications within the cluster and the average with emphasis on extreme values (E) obtained in a single cluster were analyzed and matched with pathologic results. RESULTS: In the malignant group of cases, the mean values of the standard average length and area were significantly higher (P < .0001) than the mean values in the benign group. Distribution analysis demonstrated that an average length of more than 0.41 mm was associated with malignant lesions 77% of the time, while an average length of less than 0.41 mm was associated with benign lesions 71% of the time. The mean of the average length (E) and area (E) of microcalcifications within the cluster demonstrated an even higher discriminative power when compared with the standard average length and area. The average brightness, on the other hand, showed only a low discriminative power. CONCLUSION: Digital computerized analysis of mammographically detected calcifications demonstrated that the average length and area of the calcifications in benign clusters were significantly smaller than those in malignant clusters.
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Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Mamografía/métodos , Interpretación de Imagen Radiográfica Asistida por Computador , Adulto , Anciano , Neoplasias de la Mama/patología , Calcinosis/patología , Reacciones Falso Positivas , Femenino , Humanos , Persona de Mediana Edad , Curva ROC , Estudios RetrospectivosRESUMEN
BACKGROUND: The ultimate therapy for acute cholecystitis is cholecystectomy. However, in critically ill elderly patients the mortality of emergency cholecystectomy may reach up to 30%. Open cholecystostomy performed under local anesthesia was considered to be the procedure of choice for treatment of acute cholecystitis in high-risk patients. In recent years, ultrasound- or computed tomography (CT)-guided percutaneous transhepatic cholecystostomy (PTHC) replaced open cholecystostomy for the treatment of acute cholecystitis in critically ill patients. METHODS: The aim of the present study was to evaluate the results of a 5-year protocol using PTHC followed by delayed laparoscopic cholecystectomy for the treatment of acute cholecystitis in critically ill patients. We reviewed the charts of 55 patients who underwent PTHC at the Hadassah University Hospital Mount Scopus during the years 1994 to 1999. RESULTS: The main indications for PTHC among this group of severely sick and high-risk patients was biliary sepsis and septic shock in 23 patients (42%); and severe comorbidities in 32 patients (58%). The median age was 74 (32 to 98) years, 33 were female and 22 male. Successful biliary drainage by PTHC was achieved in 54 of 55 (98%) of the patients. The majority of the patients (31 of 55) were drained transhepaticlly under CT guidance. The rest, (24 of 55) were drained using ultrasound guidance followed by cholecystography for verification. Complications included hepatic bleeding that required surgical intervention in 1 patient and dislodgment of the catheter in 9 patients that was reinserted in 2 patients. Three patients died of multisystem organ failure 12 to 50 days following the procedure. The remaining 52 patients recovered well with a mean hospital stay of 15.5 plus minus 11.4 days. Thirty-one patients were able to undergo delayed surgery: 28 underwent laparoscopic cholecystectomy of whom 4 (14%) were converted to open cholecystectomy. This was compared with a 1.9% conversion rate in 1,498 elective laparoscopic cholecystectomies performed at the same time period (P = 0.012). Another 3 patients underwent planned open cholecystectomy, 1 urgent and 2 combined with other abdominal procedures. There was no surgery associated mortality, severe morbidity, or bile duct injury. CONCLUSIONS: The use of PTHC in critically ill patients with acute cholecystitis is both safe and effective.