Bone Scan: Indications Revisited.

Skeletal scintigraphy is one of the most widely performed investigations in any nuclear medicine department. However, there has been a paradigm shift in the indications for which bone scan was performed in the past 3 decades, mainly due to advancement in other imaging modalities, better disease understanding, and the development of newer disease-specific guidelines. The metastatic indications for bone scans accounted for 60.3% of cases in 1998 which reduced to 15.5% in 2021 and nonmetastatic indications rose from 39.7% in 1998 to 84.5% in 2021. Fewer bone scans are being performed for the metastatic survey, and more scans are being performed for nononcological orthopedic and rheumatological indications. This article captures the journey of skeletal scintigraphy in the past three decades.

Appropriate use criteria in myocardial perfusion imaging in a tertiary care hospital in South India: An audit.

Myocardial perfusion imaging (MPI) is an important investigative tool in the diagnosis and management of coronary artery disease. This investigation has seen a manifold increase in number in past decades as compared to other investigations such as cardiac magnetic resonance imaging/positron emission tomography or computed tomography. In 2005, "Appropriate use criteria (AUC) in cardiac radionuclide imaging" was formulated by the American College of Cardiology Foundation and the American Society of Nuclear Cardiology for effective use of this investigation, later revised in 2009. We assessed the appropriateness of indications for MPI in patients presenting to the nuclear medicine department of a tertiary care hospital according to the latest AUC for cardiac radionuclide imaging. This is a retrospective analysis of all cardiac perfusion scans performed from June 2019 to January 2020 in a tertiary care teaching hospital in South India. All patients' indications for MPI were assessed for appropriateness using AUC 2009 as appropriate, inappropriate, and uncertain indications by two experienced nuclear medicine physicians blinded for results of the test and hospital stay of the patients. A total of 1015 cardiac scans were performed in the given period, which were analyzed. This included 613 males and 402 females, with most of the patients aged above 60 years (n = 640; males = 385, females = 255). Most of the patients had diabetes mellitus or hypertension or both except in 161 patients (15.8%) which did not have either of the comorbidities. Chest pain and/or shortness of breath were the most common presenting complaints. The appropriate indication for imaging was found in 784 patients (77.2%), inappropriate in 121 patients (12%), and uncertain in 110 patients (10.8%). Our results showed appropriate indication to be 77.2% and inappropriate indications as 12% for MPI referrals in a tertiary care teaching hospital, similar to Western literature but can be improved further by continued teaching and awareness campaigns.

Technetium-99m methylene diphosphonate bone scan in evaluation of insufficiency fractures - A pictorial assay and experience from South India.

Insufficiency fractures (IFs) can be challenging to diagnose due to varied presentations, and sometimes, it changes the course of treatment, as in cancer patients in whom it has to be differentiated with metastatic disease. We present the role of Technetium 99m methylene diphosphonate (99mTc-MDP) bone scan, which is a low-cost, simple to perform, whole body diagnostic investigation in the diagnosis of IFs. This is a retrospective analysis of all patients who underwent a 99mTc-MDP bone scan in a tertiary care teaching hospital during 2013-2017 and were diagnosed as having an IF on bone scan. The bone scans were performed on a dual-head gamma camera using low-energy high-resolution collimators. Of all the bone scan performed during 2013-2017, a total of 138 patients with a mean age of 57.5 ± 14.7 years were diagnosed as having IFs based on bone scan and final clinical diagnosis. Among them, the most common complaint was regional bony pain in 62% of patients, while the most common cause was osteoporosis in 47% of patients, both postmenopausal and senile osteoporosis. In all, 265 sites of fractures were identified with a fracture average of 1.9/patient, the most common site being dorsolumbar vertebrae, followed by ribs and lower limb bones. Many unusual sites were also identified such as talus, sternum, clavicle, and scapula. 99mTc-MDP bone scan, being noninvasive whole-body imaging, is a useful investigation for evaluation of IFs and in correlation with biochemical analysis and other imaging can be used to determine the etiology of IF.

Iliac Insufficiency Fracture: "Bow Sign" on Bone Scan.

Pelvic insufficiency fractures (IFs) are frequently diagnosed on technetium-99m methylene diphosphonate bone scan (BS), where it remains an important diagnostic imaging modality. Involvement of iliac bone in pelvic IFs is very rare. Differentiation from metastases is crucial where BS shows characteristic appearance obviating the need for further investigations for confirmation. There are many diagnostic appearances reported on BS for the diagnosis of IFs at various sites. We present a patient with cervical carcinoma who was previously treated with external beam radiotherapy to pelvis and now presented with pelvic pain. BS was performed to rule out skeletal metastases, however, the findings were diagnostic for iliac IF.