Area of ischemia assessed by physicians and software packages from myocardial perfusion scintigrams.

The European Society of Cardiology recommends that patients with >10% area of ischemia should receive revascularization. We investigated inter-observer variability for the extent of ischemic defects reported by different physicians and by different software tools, and if inter-observer variability was reduced when the physicians were provided with a computerized suggestion of the defects

Diagnostic evaluation of three cardiac software packages using a consecutive group of patients

Purpose: The aim of this study was to compare the diagnostic performance of the three software packages 4DMSPECT (4DM), Emory Cardiac Toolbox (ECTb), and Cedars Quantitative Perfusion SPECT (QPS) for quantification of myocardial perfusion scintigram (MPS) using a large group of consecutive patients. Methods: We studied 1,052 consecutive patients who underwent 2-day stress/rest 99mTc-sestamibi MPS studies. The reference/gold-standard classifications for the MPS studies were obtained from three physicians, with more than 25 years each of experience in nuclear cardiology, who re-evaluated all MPS images. Automatic processing was carried out using 4DM, ECTb, and QPS software packages. Total stress defect extent (TDE) and summed stress score (SSS) based on a 17-segment model were obtained from the software packages. Receiver-operating characteristic (ROC) analysis was performed. Results: A total of 734 patients were classified as normal and the remaining 318 were classified as having infarction and/or ischemia. The performance of the software packages calculated as the area under the SSS ROC curve were 0.87 for 4DM, 0.80 for QPS, and 0.76 for ECTb (QPS vs. ECTb p = 0.03; other differences p < 0.0001). The area under the TDE ROC curve were 0.87 for 4DM, 0.82 for QPS, and 0.76 for ECTb (QPS vs. ECTb p = 0.0005; other differences p < 0.0001). Conclusion: There are considerable differences in performance between the three software packages with 4DM showing the best performance and ECTb the worst. These differences in performance should be taken in consideration when software packages are used in clinical routine or in clinical studies

Perfusion vector - a new method to quantify myocardial perfusion scintigraphy images: a simulation study with validation in patients

The interpretation of myocardial perfusion scintigraphy (MPS) largely relies on visual assessment by the physician of the localization and extent of a perfusion defect. The aim of this study was to introduce the concept of the perfusion vector as a new objective quantitative method for further assisting the visual interpretation and to test the concept using simulated MPS images as well as patients

Validation of an automated method to quantify stress-induced ischemia and infarction in rest-stress myocardial perfusion SPECT.

Myocardial perfusion SPECT (MPS) is one of the frequently used methods for quantification of perfusion defects in patients with known or suspected coronary artery disease. This article describes open access software for automated quantification in MPS of stress-induced ischemia and infarction and provides phantom and in vivo validation

The Implications of Cost-Effectiveness Analysis of Medical Technology

A study by the Office of Technology Assessment (OTA) that examines the efficacy and cost-effectiveness of cardiac radionuclide imaging, a new diagnostic technology used in the diagnosis and management of heart disease

Progress Report No. 14

Progress report of the Biomedical Computer Laboratory, covering period 1 July 1977 to 30 June 1978

Progress Report No. 15

Progress report of the Biomedical Computer Laboratory, covering period 1 July 1978 to 30 June 1979

Viabilidad del vector perfusión para el diagnóstico de pacientes sometidos a estudios de perfusión miocárdica mediante técnica de Spect

El trabajo descrito en el presente artículo fue realizado con el fin de identificar la viabilidad del método Vector Perfusión, como una herramienta diagnóstica automatizada en los estudios por SPECT de pacientes con sospecha de afecciones isquémicas del ventrículo izquierdo del corazón. Para lo cual se desarrolló un algoritmo automatizado para la aplicación del método sobre imágenes de pacientes reales, concluyendo en la obtención de dos vectores por paciente: para etapa de reposo y estrés fármaco-inducido; posteriormente dichos vectores fueron comparados con los diagnósticos que generaron médicos nucleares sobre las imágenes estudiadas. Resultando en un ejercicio de intercomparación método-especialista con resultados satisfactorios en la mayoría de casos, sin embargo con la evidencia de un foco de error generalizado con una repercusión severa en el éxito del método: el procedimiento asociado al acondicionamiento de las imágenes diagnósticas.The investigation work described in this article was carried out in order to identify the viability of the Vector Perfusion method, as an automated diagnostic tool in the SPECT studies of patients with suspected ischemic affections of the left ventricle of the heart. For which an automated algorithm was developed for the application of the method on images of real patients, concluding in obtaining two vectors per patient: for resting stage and drug-induced stress; later, these vectors were compared with the diagnoses generated by nuclear physicians on the images studied. Resulting in an inter-comparison exe6rcise method-specialist with satisfactory results in most cases, however with the evidence of a generalized focus of error with a severe impact on the success of the method: the procedure associated with the conditioning of diagnostic images.Magíster en Física MédicaMaestrí