A Matlab Tool for Tumor Localization in Parathyroid Sestamibi Scintigraphy

Submarine method for localization of parathyroid tumors (PT) has proved to be effective in case of typical pitfalls of conventional scintigraphic methods (combined subtraction and double phase methods). It uses images obtained by standard dynamic parathyroid sestamibi scintigraphy suggested by European Association of Nuclear Medicine. This paper presents: 1) the developed Matlab interface that enables the implementation and evaluation of algorithms for the automatic application of Submarine method; 2) the algorithm for automatic extraction of the entire thyroid region from the background radioactivity using operations from mathematical morphology applied on dynamic scintigrams; 3) the results obtained by algorithm for localization and visualization of PTs based on estimation of exponential decreasing trend of time-activity curves. The algorithm was tested on a group of 20 patients with histopathologically proven PTs using developed Matlab interface

Parathyroid dual tracer subtraction scintigraphy: small regions method for quantitative assessment of parathyroid adenoma uptake.

OBJECTIVE: The aim was quantitative assessment of parathyroid adenoma (PTA) uptake in dual tracer dynamic scintigraphy. METHODS: In 78 patients, median age 58 (19-80) years, surgically treated for primary hyperparathyroidism (PHPT), with parathyroid hormone median 125 (70-658) pg/ml, we performed preoperative parathyroid scintigraphy, following EANM guidelines of subtraction and double-phase protocol (2009) using two tracers: Tc-99m pertechnetate and Tc-99m MIBI. In addition to standard subtraction processing and visual interpretation of delayed MIBI planar images of neck and mediastinum in oblique sections (positions according to ultrasound PTA localisation), we developed Submarine processing software that enables selecting custom regions grid sizes ≥6 mm (as this solution was not present in commercial software) to follow time activity curve changes in thyroid tissue and PTA. Histopathology in 53/78 patients revealed PHPT and in 25/78 patients thyroid nodular disease only, and thyroid malignancy occurred in total of 15/78 (19 %) patients. PHPT group included 44 solitary PTA, 8 patients with hyperplasia and one parathyroid carcinoma. The median macroscopic volume of PTA was 717.5 (15-6125) mm(3). Concomitant PHPT and thyroid nodular disease occurred in 24/53 patients and among them 8 patients had thyroid malignancies. RESULTS: PTA showed typical pattern of late peak on time activity curves characterized by median start time on 15 (10-25) min, the peak amplitude mean 19 (±5) % above thyroid declining washout curve, and duration of peak 6 (4-10) min, allowing PTA to "emerge" like submarine, independent from thyroid tissue and lesions. The ratio of PTA-to-normal thyroid uptake at peak maximum was 1.35 (±0.21). The thyroid TACs results of normal 29/78 (37 %) patients, benign nodular 34/78 (44 %) patients, and malignancy in 15 (19 %) patients were all presented by declining exponential curves. The slope analysis of TACs in normal thyroid tissue, thyroid benign and malignant lesions (linear fitted logarithm of TAC) showed no difference (the same negative slope: -0.04). Submarine processing was sensitive in detection of small lesions, in hyperplasia, and concomitant thyroid nodular disease. CONCLUSIONS: The novel Submarine processing confirmed specific PHPT pattern and was effective in the group with potential pitfalls of standard interpretation, increasing sensitivity and specificity of standard processing subtraction algorithm. Prolonged MIBI accumulation was present in malignant as well as benign thyroid nodules with identical TAC slope

A Software Tool for the Assessment of Salivary Gland Function

Salivary gland scintigraphy (SGS) is a noninvasive, simple and reproducible technique for the functional evaluation of salivary gland involvement in patients with Sjögren’s syndrome. Using Labview environment (National Instruments, Austin, Texas) we have developed a software tool for the automatic calculation of most commonly investigated salivary and oral indices derived from salivary time-activity curves. We have shown examples that illustrate the application of the software. Our software enables the comparison of findings among several research centers with the aim of standardizing a processing protocol, defining the reference values of quantitative indices and introducing new salivary indices