Positive Diagnosis Rate Research Articles

Real-time ultrasound evaluation of renal transplant failure during the early postoperative period

In a prospective clinical trial 385 ultrasound (US) examinations were performed on 50 renal allograft patients. Baseline sonograms were obtained within 24 hrs of transplantation, and serial US examinations were performed in two to three days intervals during hospital recovery. 24 out of 28 cases of acute rejections (85.7%) were detected by US with an 8% false positive rate. Using statistical analysis, enlarged and sonolucent pyramids, areas of decreased parenchymal echogenicity and an increase in anterior-posterior diameter of the organ, proved to be the best US-rejection criteria. Fine needle aspiration cytology revealed a high rate of false positive rejection diagnosis (23.8%). The results demonstrate that US is a valuable diagnostic aid in the evaluation of postoperative renal transplant failure.

B-Mode Sonographie des Halses - Vergleich der Ergebnisse der Sonographie, der Computertomographie und der Pathomorphologie*

High-resolution B-scan sonography has so far been hardly utilized in the investigation of neck tumours. The results of B-scan sonography, computed tomography, and anatomic pathology are compared and discussed. Lymph node tumours of the neck are easily and precisely recognized by ultrasonography. The rate of false positive tumours diagnoses is higher in B-scan sonography than by computed tomography. The rate of false negative diagnoses is the same with both methods. The technical development of B-scan sonography will widen its application in E.N.T. surgery.

LABORATORY DIAGNOSIS AND ORAL TREATMENT OF CAPD PERITONITIS

The laboratory diagnosis of 50 consecutive episodes of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) was studied. The technique which yielded the highest rate (84%) of positive bacteriological diagnoses was inoculation and subculture of thioglycollate broth. Cloudiness of fluid to the naked eye was an accurate predictor of a raised white cell count. A minimum laboratory protocol for the bacteriological diagnosis of CAPD peritonitis was devised and has been in use satisfactorily since the completion of the study. Antibiotic treatment was given orally in the first instance in 43 episodes and was successful in 34.

Early detection and surgical treatment of esophageal carcinoma.

From 1960-1980, the technic of abrasive cytologic examination by means of a "balloon catheter" has been used to detect esophageal carcinoma in high-incidence areas with rates of positive diagnosis varying from 87.8% to 91.9%. An application of this technic in mass screenings has led to detection of a large number of very early cases of esophageal carcinoma, of which only about 50% showed positive X-ray findings and 75% showed positive endoscopic findings. Intraluminal staining with toluidine blue through a fiberoptic esophagoscope gave a positive biopsy in 83.9%. In a 16-year period from 1964 through 1979, 237 patients with Stage I esophageal carcinoma underwent surgery. The resectability rate was 100% and the operative mortality 2.5%. Pathologic study of the resected specimens showed carcinoma in situ in 84 cases (35.4%) and early infiltrative carcinoma confined to only the mucosa and submucosa in 153 cases (64.6%). The 5- and 10-year survival rates following resection were 85.9% and 55.6%, respectively. In surgery on 1,647 patients with more advanced carcinoma of the esophagus and who underwent surgery between 1958 and 1979, (resectability rate of 83.4% and a resection mortality of 4.1%), the p-TNM histopathological classification of these patients showed that 72.3% had Stage III and 8.8% had Stage IV diseases, with either extra-esophageal tumor invasion and/or regional lymph node involvements, or distant metastases. The 5-, 10- and 15-year survivals, as calculated by the number of resections were 30.3%, 21.2% and 16.2%, respectively. Analysis showed that prognosis was related to staging of the disease, the extent of tumor invasion, length of the lesion, and the presence or absence of nodal involvement.

The potential value of liquid-crystal thermography in detecting significant mastopathy.

Liquid-crystal thermography (LCT) was assessed as a means of detecting proliferative disorders of the breast independently of other clinical or radiological data. There was no statistically significant difference between positive diagnosis rates for LCT of the breast in biopsy-proved proliferative disorders and in clinically and radiologically normal volunteers. While this experiment was not designed to evaluate LCT for detection or diagnosis of advanced, clinically occult, or minimal breast cancer, the data suggest that this technique can identify some large, bulky tumors, and that the smaller the lesion, the less likely that it would be detected by LCT.

The objectives of palliative surgery in pancreas cancer: a retrospective study of 73 cases.

In 73 cases of pancreas cancer, histological diagnosis was not obtained in 43 (59%). Relief of obstructive jaundice was not satisfactorilly achieved in 14 of 39 patients at risk (36%), while gastric outflow obstruction developed subsequent to surgery in eight of 31 patients at risk (26%). Fine needle aspiration cytology is advocated to improve the rate of positive peroperative tissue diagnosis. To relieve bile duct obstruction, cholecystojejunostomy is advocated only in patients with pancreas cancer who have a very short life expectancy, and only when the cystic duct is patent. Choledochojejunostomy and gastrojejunostomy "double bypass" is advocated for cancers which are macroscopically localized to the pancreatic area. The selective use of this double bypass will improve surgical palliation and minimize reoperations in cancer of the pancreas.

Endoscopic retrograde brush cytology in patients with primary and secondary malignancies of the pancreas.

Endoscopic retrograde brush cytology (ERBC) was performed in 29 patients with primary pancreatic malignancies verified later by histology. Results were positive in 21 patients, suspicious in five, and negative in three. ERBC performed in seven patients with uncertain findings at endoscopic retrograde cholangiopancreatography (ERCP) was positive for malignancy in six and suspicious in one. Endoscopic aspiration cytology (EAC) performed in 10 patients with primary tumours was positive for malignancy in three, suspicious in two, and negative in five cases. ERBC and/or EAC performed in five cases with secondary tumours were positive for malignancy in one and negative in four. It is concluded that ERBC gives a high rate of positive or suspicious (90%) diagnosis of malignancy in patients with primary pancreatic lesions. In secondary tumours cytology seems to be negative in most cases. The study further shows that many of the malignant tumours found by ERP are secondary lesions. Cytology is often able to detect malignancy when ERP has proved inconclusive.

Diagnostic accuracy of CT in circumscript liver disease

To evaluate the accuracy of CT in diagnosing circumscript liver disease, CT findings in 105 patients were compared to the results of invasive diagnostic procedures (laparoscopy, laparotomy, and autopsy). In all patients at least one of these procedures was performed in addition to CT. CT proved to be a valuable noninvasive method in detecting and differentiating circumscript liver lesions such us metastases, primary liver tumors, solitary cysts and polycystic disease, abscesses, and echinococciasis. The 10% rate of false positive and false negative diagnoses indicates the limitations of the method.

Automatic real time arrhythmia monitoring in the intensive coronary care unit

A prospective study was carried out to evaluate accuracy of a real time computer system for arrhythmia monitoring in a coronary care unit. QRS complexes in 57 continuously recorded 30 minute electrocardiographic rhythm strips from 30 patients were classified by the computer. Blinded interpretation of each beat was made by a cardiologist. A total of 146,638 QRS complexes were classified during the monitoring period of 1,710 minutes. The accuracy rate of computer detection was 99.94%. During this period 67 artifacts were identified as beats. The computer correctly identified 5,467 of 5,729 ventricular premature beats (accuracy of detection rate 95.46%). The incidence rate of false positive diagnosis of beats other than ventricular ectopic beats was 0.1%. The rate of computer accuracy in detecting ventricular premature beats was 93.33% in two patients with atrial fibrillation. In individual patients, computer interpretation did not deviate from the cardiologist's interpretation by more than 1 beat/min. The rate of computer accuracy in detecting supraventricular premature beats was lower (82.45%). The distinctly improved accuracy of computer monitoring of ventricular arrhythmia in a coronary care unit reported is the result of a new algorithm. This approach combines major elements of cross correlation of QRS signals as well as grouping of complexes into families. Normal and abnormal templates are stored and newly detected QRS complexes are matched. The program appears to be sufficiently accurate to warrant further applications.

Correlation of electrocardiogram and vectorcardiogram with coronary occlusion and myocardial contraction abnormality

Electrocardiograms and Frank vectorcardiograms were recorded in 156 consecutive patients with total occlusion of at least one coronary artery (on arteriography) and associated left ventricular contraction abnormality (on ventriculography). The angiograms and cardiograms were independently reviewed. In the presence of single vessel occlusion, appropriate vectorcardiographic diagnosis of myocardial infarction was determined in 118 of 156 cases (76 percent) compared with a lower electrocardiographic detection rate in 77 of 156 cases (49 percent). Findings diagnostic of two coexisting infarctions were observed in 71 percent of vectorcardiograms and 37 percent of electrocardiograms in 51 patients with double vessel occlusion and two areas of left ventricular dyskinesia. The vectorcardiographic detection rate was similarly superior to the electrocardiographic rate in the presence of subtotal coronary occlusion and myocardial asynergy in single (73 percent versus 53 percent) and double (53 percent versus 28 percent) vessel disease. The incidence rate of false positive diagnoses was 3 percent for electrocardiography and 4 percent for vectorcardiography. It is concluded that the vectorcardiogram is superior to the electrocardiogram in the diagnosis of obstructive coronary artery disease and left ventricular contraction abnormality.

The effect of intellectual level on the rate of false positive organic diagnoses from the Hewson and Adolescent ratios

The effect of intellectual level on the rate of false positive organic diagnoses from the Hewson and Adolescent ratios