No abstract

BACKGROUND: Several parathyroid scintigraphy protocols have been used for preoperative localization of hyperfunctioning parathyroid glands in patients with hyperparathyroidism. The aim of this study is to compare the diagnostic accuracy of vari-

Purpose Diagnostic I-131 MIBG scintigraphy is an important imaging modality for evaluation of patients with neuroblastoma (NB) especially in centers where I-123 MIBG is not available. Single photon emission computed tomography/computed tomography (SPECT/CT) could potentially improve lesion detection over planar scintigraphy, but studies regarding its usefulness as an add-on to diagnostic I-131 MIBG scintigraphy are limited. This study aimed to determine the usefulness and factors related to usefulness of SPECT/CT in diagnostic I-131 MIBG scintigraphy in NB patients. Methods Usefulness of SPECT/CT for lesion detection, lesion localization, resolving suspicious findings, and clarifying the nature of lesions on anatomical imaging were retrospectively reviewed in 86 diagnostic planar I-131 MIBG scintigrams with addon SPECT/CT. Results SPECT/CT detected additional lesions in 23.2%(20/86), helped localize lesions in 21.1%(8/38), resolved suspicious findings in 85.7%(6/7), determined functional status of lesions on anatomical imaging in 94.4%(17/18), and changed diagnosis from a negative to a positive study in 19.5%(8/41). Independent predictors of SPECT/CT being useful included presence of suspicious findings on planar imaging (OR 99.08; 95% C.I. 6.99-1404.41; p = 0.001), positive findings on planar imaging (OR 4.61; 95% C.I. 1.05, 20.28; p < 0.001), and presence of structural lesions on anatomical imaging (OR 32.54;; p < 0.001). Conclusion SPECT/CT is a useful add-on to diagnostic planar I-131 MIBG scintigraphy. Predictors of usefulness of SPECT/CT include suspicious or positive findings on planar scintigraphy and the presence of structural lesions on anatomical imaging.

Deep vein thrombosis (DVT) is a serious medical condition that needs prompt diagnosis and treatment. The invasive gold standard contrast venography has largely been replaced by venous ultrasonography which is currently the imaging modality of choice for DVT diagnosis. Radionuclide venography (RNV) is an alternative test for DVT, but a few studies have directly compared RNV with venous ultrasonography. This study aims to determine the agreement between RNV and venous ultrasonography for diagnosis of DVT and to determine the predictive value of different RNV findings for the prediction of DVT as detected by venous ultrasonography. Imaging results from patients who underwent both RNV and venous ultrasonography for suspected DVT no more than 1 week apart were reviewed. Results from both modalities were compared to determine inter-modality agreement. A total of 121 venous segments from 102 lower limbs of 75 patients could be compared. The prevalence of DVT as detected by venous ultrasonography was 39%. RNV and venous ultrasonography had moderate agreement (73.6% agreement, κ =0.48, P < 0.0001). The absence of radiotracer activity from a deep venous segment had a positive predictive value (PPV) of 100% for DVT. Other findings such as isolated great saphenous vein activity had a lower PPV. The negative predictive value of RNV is 97.5% with only one patient out of forty with normal RNV found to have DVT by venous ultrasonography, which suggests that DVT can virtually be excluded in patients with normal RNV.

No abstract