Search results for "specificity"

Automatic detection of lung nodules in CT datasets based on stable 3D mass–spring models

2012

We propose a computer-aided detection (CAD) system which can detect small-sized (from 3 mm) pulmonary nodules in spiral CT scans. A pulmonary nodule is a small lesion in the lungs, round-shaped (parenchymal nodule) or worm-shaped (juxtapleural nodule). Both kinds of lesions have a radio-density greater than lung parenchyma, thus appearing white on the images. Lung nodules might indicate a lung cancer and their early stage detection arguably improves the patient survival rate. CT is considered to be the most accurate imaging modality for nodule detection. However, the large amount of data per examination makes the full analysis difficult, leading to omission of nodules by the radiologist. We…

Association between night/after-hours surgery and mortality: a systematic review and meta-analysis

2020

Abstract Background The association between night/after-hours surgery and patients' mortality is unclear. Methods The protocol of this systematic review was registered in PROSPERO (CRD42019128534). We searched Medline, PubMed, and EMBASE from inception until August 29, 2019 for studies examining an association between timing of surgical procedures (time of anaesthesia induction or surgery start) and mortality (within 30 days or in-hospital) in adult patients. Studies reporting patients' mortality after surgery performed during the weekend only were excluded. All analyses were done using the random-effects model. Results We included 40 observational studies (36 retrospective and four prospec…

Undetected Malignancies of the Breast: Dynamic Contrast-enhanced MR Imaging at 1.0 T

2002

To assess the prevalence and characteristics of malignant breast lesions not identified with magnetic resonance (MR) imaging.Breast tissue specimens were obtained in 464 of 967 patients who had undergone dynamic gadolinium-enhanced T1-weighted fast low-angle shot three-dimensional MR imaging of both breasts. A comparison of sensitivity, specificity, and predictive values of the prospectively recorded findings of mammography, ultrasonography (US), and MR imaging with the histopathologic results was performed with receiver operating characteristic (ROC) curve analysis. MR imaging examination findings that caused a false-negative diagnosis were reviewed to identify possible sources of error.Hi…

Graph-matching based CTA.

2009

Separating bone, calcification, and vessels in computer tomography angiography (CTA) allows for a detailed diagnosis of vessel stenosis. This paper presents a new, graph-based technique that solves this difficult problem with high accuracy. The approach requires one native data set and one that is contrast enhanced. On each data set, an attributed level-graph is derived and both graphs are matched by dynamic programming to differentiate between bone, on one hand side, and vessel/calcification on the other hand side. Lumen and calcified regions are then separated by a profile technique. Evaluation is based on data from vessels of pelvis and lower extremities of elderly patients. Due to subst…

Non‐invasive diagnostic techniques in pigmentary skin disorders and skin cancer

2021

Background Diagnosis of pigmentary skin disorders, pre-cancerous and cancerous skin diseases is traditionally relied on visual assessment. The most widely applied invasive diagnostic technique is the skin biopsy. There have been significant technological advances in non-invasive diagnostic methods for skin disorders. Objective The objective of this article is to discuss different non-invasive diagnostic modalities, used in the diagnosis of pigmentary skin disorders and cutaneous cancers. Methods Comprehensive literature search was performed to screen articles related to non-invasive diagnostic techniques in pigmentary skin disorders and cutaneous cancers. Articles published in journals inde…

An unusual otomicroscopy diagnosis.

2003

Endoscopic Ultrasonography in the Diagnosis of Regional Lymph Nodes in Esophageal and Gastric Cancer - Results of Studies in Vitro

1993

A total of 90 regional lymph nodes (43 benign/47 metastatic) from 16 surgical resection specimens of patients with esophageal and gastric carcinoma were examined in vitro by endosonography. The validity of endosonographic criteria of lymph node dignity (size, echogenicity, internal echo pattern and margin structure) was assessed using computer-supported B-mode analysis and compared to histopathological results. Of 26 lymph nodes with a diameter of more than 10 mm, 19 were metastatic (72%). The subjective assessment of the internal echo pattern (homogeneity) and the node margins by an experienced observer allowed the diagnosis of metastatic lymph nodes, but there was a high proportion of fal…

Diagnostic Value of Prenatal MR Imaging in the Detection of Brain Malformations in Fetuses before the 26th Week of Gestational Age.

2016

BACKGROUND AND PURPOSE: In several countries, laws and regulations allow abortion for medical reasons within 24–25 weeks of gestational age. We investigated the diagnostic value of prenatal MR imaging for brain malformations within 25 weeks of gestational age. MATERIALS AND METHODS: We retrospectively included fetuses within 25 weeks of gestational age who had undergone both prenatal and postnatal MR imaging of the brain between 2002 and 2014. Two senior pediatric neuroradiologists evaluated prenatal MR imaging examinations blinded to postnatal MR imaging findings. With postnatal MR imaging used as the reference standard, we calculated the sensitivity, specificity, positive predictive value…

Newborn screening of inherited metabolic disorders by tandem mass spectrometry: past, present and future

2013

Inborn errors of metabolism are inherited biochemical disorders caused by lack of a functional enzyme, transmembrane transporter, or similar protein, which then results in blockage of the corresponding metabolic pathway. Taken individually, inborn errors of metabolism are rare. However, as a group these diseases are relatively frequent and they may account for most of neonatal mortality and need of health resources. The detection of genetic metabolic disorders should occur in a pre-symptomatic phase. Recently, the introduction of the tandem mass spectrometric methods for metabolite analysis has changed our ability to detect intermediates of metabolism in smaller samples and provides the mea…

Is preoperative radiographic localization of islet cell tumors in patients with insulinoma necessary?

1993

Preoperative localization tests [sonography, computed tomography, angiography, percutaneous transhepatic portal venous sampling for insulin radioimmunoassay (PTP)] have a sensitivity of 60% to 90% in cases of organic hyperinsulinism. In all publications, however, the sensitivity of intraoperative localization, 75% to 100%, is distinctly higher. With the exception of PTP, all tumors that can be identified by preoperative localization can also be detected using palpation or intraoperative sonography. Preoperative localization diagnosis is therefore not absolutely necessary prior to primary operation in the case of organic hyperinsulinism. It is requested by many surgeons because: (1) only a f…