Asia Oceania Journal of Nuclear Medicine and Biology最新文献

Tuberculous pyomyositis is a rare and often under-recognized extrapulmonary manifestation of tuberculosis, presenting with non-specific symptoms such as fever and abscess, that may delay diagnosis. We report a unique case of disseminated tuberculous pyomyositis in a 56-year-old male with underlying chronic inflammatory arthritis. The diagnosis was confirmed using CBNAAT, line probe assay (LPA), and histopathology. Currently MRI is the standard imaging modality in use for imaging pyomyositis. ¹⁸F-FDG PET/CT can play a crucial role in detecting widespread metabolically active lesions involving multiple skeletal muscle groups and lymph nodes, which are not fully appreciated on conventional imaging and prove to be a sensitive imaging modality in such cases. This imaging modality provided a comprehensive assessment of disease burden, helping to map the full extent of involvement and guide clinical management. Early identification and treatment are essential, especially in atypical or disseminated cases, to prevent further complications and improve patient outcomes. Here we present a rare case presentation of such extensive muscular involvement in tuberculosis, highlighting the diagnostic utility of PET/CT in extrapulmonary TB.

Objectives: This study aimed to systematically evaluate the diagnostic accuracy of hepatobiliary scintigraphy (HBS) for detecting bile leaks in post-traumatic and postoperative settings, given the increasing incidence of such complications following hepatobiliary surgeries and abdominal trauma.

Methods: A systematic review and meta-analysis were conducted in accordance with the PRISMA guidelines. Literature searches of PubMed, Embase, and Scopus databases were performed through June 19, 2025. Studies were included if they assessed patients with suspected bile leak using HBS and reported sufficient data to construct diagnostic contingency tables. The quality of included studies was assessed using the QUADAS-2 tool. Pooled sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall diagnostic accuracy were calculated. Subgroup analyses evaluated diagnostic performance across clinical contexts such as post-trauma, liver transplant/resection, and cholecystectomy.

Results: Sixteen studies with 673 patients were included. The pooled sensitivity and specificity of HBS were 0.882 (95% CI: 0.81-0.93) and 0.93 (95% CI: 0.83-0.97), respectively. The pooled PPV was 0.874 and NPV was 0.965, with an area under the SROC curve of 0.94, indicating excellent diagnostic performance. Subgroup analyses showed the highest accuracy in trauma patients, while specificity varied more in postoperative settings, particularly after liver transplant or resection.

Conclusion: HBS is a highly sensitive and reliable imaging modality for ruling out bile leaks. While variability in specificity warrants cautious interpretation in complex surgical cases, HBS should be considered a valuable first-line, non-invasive diagnostic tool in evaluating suspected bile leaks.

Objectives: Moyamoya disease (MMD) is a rare, progressive steno-occlusive cerebrovascular disorder characterized by impaired cerebral perfusion and an elevated risk of ischemic events. Accurate cerebrovascular reserve (CVR) assessment is crucial for guiding surgical decision-making. This study evaluated the clinical utility of acetazolamide (ACZ)-challenged brain perfusion single-photon emission computed tomography (SPECT) in assessing CVR in patients with MMD.

Methods: We retrospectively analyzed 10 patients (6 males, four females; aged 5-65 years) with angiographically confirmed MMD who underwent baseline and post-ACZ ^99mTc-ECD SPECT. Regional perfusion across 12 brain regions per patient was visually graded and classified using Rogg's criteria (Type I-III) to assess CVR.

Results: At baseline, 78/120 regions showed normal perfusion; post-ACZ, this decreased to 72 regions, with an increase in severe hypoperfusion (from 16 to 26 regions). A total of 44 regions demonstrated improved perfusion following ACZ, indicating preserved reserve. According to Rogg's classification, 63 regions showed Type I, 13 showed Type II, and 39 showed Type III responses. Three patients had infarcts, with two exhibiting crossed cerebellar diaschisis. In a patient who underwent revascularization, new postoperative perfusion defects developed in regions that corresponded to preoperative Type III responses.

Conclusion: ACZ-challenged SPECT effectively characterizes regional CVR in MMD. Identifying Type II and III responses is a valuable predictor for ischemic vulnerability and guides the selection of surgical candidates.

Objectives: Due to its prevalence worldwide, osteoporosis is regarded as a significant public health issue. Numerous risk factors can contribute to the development of osteoporosis, leading to bone fractures. This study aimed to determine the association of parity, age, gender, origin, and pre-existing clinical conditions with low bone density of people residing in the Southeastern region of Bangladesh.

Methods: This retrospective study included a cohort of 628 individuals seeking bone mineral density (BMD) assessments using Dual Energy X-ray Absorptiometry (DXA). Association of BMD with five contributing factors (age, gender, origin, parity of the female participants and pre-existing clinical conditions i.e., hypertension, diabetes) was studied.

Results: This study included 84% female and 16% male participants. The mean BMD was found significantly lesser in older participants (aged >50 years) (P=.0.001)for both sites of lumbar spine (LS) and femoral neck (FN)). It also varied significantly in both skeletal sites, depending on the gender (P<0.001and P=0.027respectively). Rural participants were found with lower BMD than urban one (P<0.001and P=0.037respectively). BMDs of LS and FN were found to have significant negative correlations with age (-0.201 and -0.280) and parity (-0.317 and -0.236). Diabetic participants were found to have higher bone density in this study (P=0.002 and P<0.001) compared with the non-diabetic. Multivariate regression analysis also revealed statistically significant associations of BMD with gender (P<0.001), age (P<0.001), and origin (P=0.001) for the lumbar spine and with gender (P=0.002) and age (P<0.001) for the femoral neck. A significant decrease in mean BMD was also found in multiparous (parity ≥3) females compared to low parity (parity 1-2) and nulliparous (parity 0) females (P<0.001 and P=0.048 respectively for LS and FN).

Conclusion: A proactive approach to prevent osteoporosis in the study population involves a meticulous investigation of its etiological factors and addressing them precedently. Therefore, it is recommended to consider BMD as a routine test for prevention, early detection, and to minimize the sequelae of osteoporosis.

Diagnosing gastrointestinal bleeding (GIB) can be especially difficult when endoscopic evaluation do not reveal a clear source. In this report, we describe 20 patients with suspected GIB in whom initial evaluations were inconclusive. All underwent dynamic planar ^99mTc-RBC scintigraphy followed by SPECT/CT imaging. This combination proved valuable in either identifying active bleeding sites or clarifying non-bleeding causes of tracer accumulation. The added anatomical detail from SPECT/CT helped distinguish true bleeding from normal physiological activity, vascular landmarks, or postoperative alterations-areas where planar imaging is not enough. In some patients, imperfect red blood cell labeling introduced challenges in image interpretation, occasionally mimicking bleeding. Even so, the fusion of functional and anatomical data improved diagnostic clarity in most cases. This series emphasizes how hybrid nuclear imaging can provide critical insight when other diagnostic methods fail, enabling more accurate localization and better-informed clinical decisions. Our experience supports the broader use of SPECT/CT in evaluating complex or obscure GIB, offering clinicians a noninvasive yet highly informative diagnostic option.

Objectives: To establish normal ranges for [^99mTc] Tc-Mebrofenin hepatobiliary scintigraphy (HBS) indices of liver function and the associated uncertainty in clinical measures due to region placement.

Methods: 47 patients referred for gallbladder assessment with no history of liver disease were included in the study. Patients underwent dynamic HBS following injection of 200 MBq of [^99mTc] Tc-Mebrofenin at 10 seconds/frame for 36 frames. Analysis was performed by 5 experienced technologists using in-house software (MIM Software, Cleveland, Ohio) to establish blood pool (BP) clearance rate (%/min), blood clearance half-time (min), mebrofenin liver uptake rate (MUR) (%/min) and MUR normalised to body-surface-area (MUR_BSA) (%/min/m²). Limits of normal ranges (95%) were established and correlation of functional indices with age was investigated. Analysis was repeated after a minimum of 4 weeks to establish intra-user variability and uncertainty associated with measures.

Results: Data were collected for 27 women and 20 men, with an age range of 20 - 81 years. Twenty-seven patients were aged over 50 and 20 patients were aged below 50. The data were found to have a normal distribution. The mean values derived for the entire cohort for BP clearance rate, blood clearance half time, MUR, and MUR_BSA were 16.8±2.6 %/min, 4.3±0.7 min, 14.4±2.0 %/min and 8.0±1.5 %/min/m², respectively. No significant difference in values was found between age groups and no correlation between liver function and age was found. The lower range of normal for MUR_BSA was established as 5.1%/min/m², with clinical measures expected to have an uncertainty of ±0. 6 %/min/m².

Conclusion: The MUR_BSA value for a patient with normal liver function can be expected to be approximately 8.0±1.5 %/min/m², with a lower limit of normal function at 5.1 %/min/m². Patients receiving liver surgery or treatment that express MUR_BSA values below this may be at higher risk and should potentially be treated with caution.

Objectives: This study aimed to evaluate the role of radioiodine uptake patterns and pulmonary nodule size in predicting progression- free survival (PFS) and overall survival (OS) in DTC patients with lung metastases only.

Methods: A retrospective study was conducted on 189 DTC patients with pulmonary metastasis alone who were treated and monitored at the Department of Nuclear Medicine, Hospital 108, Vietnam from January 2004 to December 2018. They were categorized based on radioiodine uptake patterns on post-therapy whole-body scans (WBS) and CT-based pulmonary nodule sizes. Prognostic factors were identified by Kaplan-Meier survival and Cox regression.

Results: The 5-year and 10-year OS rates were 96.83 % and 94.71 %. DTC-LM patients with diffuse radioiodine uptake and miliary metastases demonstrated significantly higher survival rates, with 5-year and 10-year PFS rates of 100% and 98.8%, respectively. In contrast, patients with nonavid metastases exhibited a markedly lower prognosis, with 5-year and 10-year PFS rates of 58.8% and 25.2%, respectively (p<0.001). Patients with nodules <5 mm had 5-year and 10-year PFS rates of 88.8% and 73.8%, respectively, while those with nodules 5-10 mm had rates of 79.8% and 52.7%. Patients with nodules ≥10 mm experienced the worst outcomes, with 5-year and 10-year PFS rates of 70.6% and 29.3% (p<0.001). Multivariate analysis confirmed that non-avid metastases, nodule size ≥10 mm, and age ≥55 were independent predictors of poor prognosis (HR:24.99, 5.96, and 6.58; p<0.001).

Conclusions: Patterns of radioiodine uptake and pulmonary nodule sizes on CT imaging are crucial predictors of long-term clinical outcomes in DTC-LM. Diffuse iodine uptake and military pulmonary metastases are associated with favorable outcomes, while non-avid lung nodules and larger nodule sizes predict poorer survival.

Obgectives: Reduced bone mineral density is often observed in breast cancer patients. Routine PET/CT scans can be used for detection of low bone mineral density. To evaluate prevalence of osteopenia, osteoporosis and fracture risk in pre and post-therapy breast carcinoma patients undergoing ¹⁸F-FDG PET/CT scans.

Methods: In this retrospective study L1-L4 vertebral and femoral neck CT mean Hounsfield unit attenuation and their corresponding SUV_max values from initial staging and end of treatment FDG PET/CT scans performed in breast carcinoma patients were compared. Post chemo ± hormonal therapy FDG PET/CT HU values were also compared to DXA scan T- scores.

Results: Significant increase in prevalence of post chemo ± hormonal therapy osteopenia, osteoporosis and fractures (62%, 18% and 16% vs baseline of 35%, 4% and 9% respectively). CECT mean attenuation values of ≤174.6 HU and ≤117.2 HU for detection of osteopenia and osteoporosis with sensitivity of 100% and specificity of 94.2 % for L1-L4 vertebrae, and ≤176.8 HU and ≤117.8 HU for osteopenia and osteoporosis with sensitivity of 100% and specificity 96.4% at femoral necks respectively were suggested. Furthermore, mean attenuation values of ≤125.9 HU with sensitivity and specificity of ~100% and 79% and ≤124.8 HU with sensitivity of 100% and specificity ~79.8% were suggested for increased L1-L4 vertebral and femoral neck fractures prevalence/ risk respectively. An associated post chemo ± hormonal therapy decline in vertebral and femoral neck mean SUV_max values in range of 14% was also observed.

Conclusions: Baseline and post chemo ± hormonal therapy follow up FDG PET/CT scans allow opportunistic evaluation and can identify a significant number of patients with osteopenia, osteoporosis and patients at increased fracture risk with a high sensitivity and good specificity. They have potential to reduce need for DXA referrals, and also enable early initiation of prophylasix and therapy.

Objectivess: To report methodology that has been developed to provide real-time monitoring of radiation emissions from subjects treated with radionuclide therapies and summarise the radioiodine retention profiles of 250 subjects treated for differentiated thyroid cancer with ¹³¹I.

Methods: A small ceiling-mounted radiation detector for continuously monitoring the exposure rate in the radiation isolation rooms has been developed. Measurements were made every minute after administration of 1-6 GBq of ¹³¹I over the one to three days typical inpatient admission. The data are saved in text format and have been fitted with a mono-exponential curve to measure retention half time.

Results: The average effective retention half time (t_½ (Eff)) for all subjects was 11.9±3.2 hrs (range: 5.0-23.1 hrs; n=250). Over 90% of the subjects had their serum TSH levels increased by injection of recombinant human TSH prior to treatment. Average retention half-time was found to be less in subjects lower than 55 year of age (t_½ (Eff)=11.5 hrs) compared to those 55 or older (t_½ (Eff)=14.4 hrs) (P=0.0007).

Conclusions: Despite the subjects, being free to move around the isolation room during admission and thus changing the source-detector geometry markedly, the system has been able to characterise their retention profiles after radioiodine treatment. These real-time measurements have applications in planning therapy and monitoring the subjects during their admission to the hospital and can be used for "live" updates for all staff as well as providing insights into the fate of radioiodine in the body.

Objectives: High levels of CXCR4 expression in patients with mantle cell lymphoma is associated with poor prognosis. Various molecular techniques used are unable to specify the metastatic disease burden. Cyclic pentapeptides act as CXCR4 antagonists hence are functional markers of in-vivo CXCR4 receptor expression. In this view, the theragnostic complex of radiolabeled ⁶⁸Ga- and ¹⁷⁷Lu-cyclic pentapeptides was developed to in-vivo target the CXCR4 receptor expression.

Methods: Bone marrow aspiration and flow cytometry were performed to examine the fraction of lymphoid cells and immunophenotyping respectively. In-vitro CXCR4 receptor expression in the biopsied sample was determined using immunohistochemistry and flow cytometry molecular techniques. Diagnostic imaging using ⁶⁸Ga-cyclic pentapeptide was performed to check the in-vivo CXCR4 expression in chemotherapy relapse MCL patient. Dosimetry studies in the same patient was performed with different time-point imaging to calculate the residence time and predict the critical organ.

Results: Bone marrow aspiration indicated ~75% atypical lymphoid cells. Flow cytometric immunophenotyping revealed positivity for CD19, CD20, CD79b, Anti-kappa markers. IHC results showed high nuclear positivity. Approximately 86.11% of the cell population showed CXCR4 positive expression. Diagnostic imaging using ⁶⁸Ga-cyclic pentapeptide showed high tracer avidity in the mesenteric mass at L4 level. The avidity of both ⁶⁸Ga- and ¹⁷⁷Lu- cyclic pentapeptide radiotracers was noted in the mesenteric mass at the L4 level. Dosimetry study using ¹⁷⁷Lu-cyclic pentapeptide indicated kidneys as the critical organ with max residence time of 5.39 h.

Conclusion: Theragnostic complex of radiolabelled ⁶⁸Ga/¹⁷⁷Lu- cyclic pentapeptides have the potential to in-vivo target the CXCR4 receptor expression.