OBJECTIVE: To establish and validate a technetium 99m sestamibi (99mTc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) nomogram for predicting non-small cell lung cancer (NSCLC). Comparing the diagnostic performance of early and delayed SPECT/CT nomogram, and compare the diagnostic performance of SPECT/CT radiomics models with single SPECT and CT radiomics models.
METHODS: This prospective study included 119 lesions (NSCLC: n = 92, benign pulmonary lesions: n = 27) from 103 patients (mean age: 59.68 ± 8.94 years). Patients underwent dual-phase 99mTc-MIBI SPECT/CT imaging. They were divided into the training (n = 83) and validation (n = 36) cohorts. Logistic regression, support vector machine, random forest, and light-gradient boosting machine were applied to train and determine the optimal machine learning model. Then, combining radiomics score and clinical factors, establish nomograms for diagnosing NSCLC.
RESULTS: CYFRA21-1 was selected for constructing the clinical model. In early imaging, the areas under the curve (AUCs) of the clinical model, radiomics model, and nomogram were 0.571, 0.830, and 0.875, respectively. The nomogram performed better than the clinical model and similarly to the radiomics model (P=0.020, P=0.216), and there are no statistically significant differences in the predictive performance between the radiomics model and the clinical model (P=0.103). In delayed imaging, the AUC was 0.643, 0.888, and 0.893, respectively. The predictive performance of the nomogram was superior compared to the clinical model and comparable to the radiomics model (P=0.042, P=0.480), and the radiomics model also demonstrated superior diagnostic performance compared to the clinical model (P=0.049). Compared to early SPECT/CT results, the AUC values of the nomogram and radiomics models in the delayed phase were higher, although no statistical differences were found (P=0.831, P=0.568). In delayed imaging, the AUC of the radiomics models for CT and SPECT was 0.696 and 0.768, respectively, SPECT/CT radiomics exhibited significant differences compared with CT and SPECT alone (P=0.042, P=0.038).
CONCLUSIONS: Dual-phase 99mTc-MIBI SPECT/CT nomograms and radiomics models can effectively predict NSCLC, providing an economically and non-invasive imaging method for diagnosing NSCLC, moreover, these findings provide a basis for early diagnosis and treatment strategies in NSCLC patients. Delayed-phase SPECT/CT imaging may offer greater practical value than early-phase imaging for diagnosing NSCLC. However, this novel approach necessitates further validation in larger, multi-center cohorts.
CONCLUSIONS: Radiomics nomogram based on SPECT/CT for discriminating NSCLC from benign lung lesions helps to aid early diagnosis and guide treatment.
CONCLUSIONS: Nomograms, based on dual-phase SPECT/CT, was constructed to discriminate between non-small cell lung cancer and benign lesions. SPECT/CT radiomics model has better predictive performance than SPECT and CT radiomics model.

Technetium-99m sestamibi single-photon emission computed tomography/computed tomography (99mTc-sestamibi SPECT/CT) is a mainstay of the pre-operative localization of parathyroid lesions. We report here the case of a 30 year-old woman with a fortuitously discovered 2 cm cervical mass for which a parathyroid origin was originally suspected due to its retro-thyroidal localization and a personal history of nephrolithiasis. Normal serum calcium and parathyroid hormone (PTH) levels excluded primary hyperparathyroidism, raising suspicion of a non-functional parathyroid adenoma, and SPECT/CT imaging showed that the mass was 99mTc-sestamibi-avid. Fine-needle aspiration (FNA) was performed; cytology was non-diagnostic but the needle washout was negative for thyroglobulin, calcitonin and PTH, arguing against a thyroidal or parathyroidal origin of the mass. Core needle biopsy revealed a schwannoma, ostensibly originating from the recurrent laryngeal nerve; upon surgical resection, it was finally found to arise from the esophageal submucosa. This case illustrates the fact that endocrinologists, radiologists, nuclear medicine, head and neck, and other specialists investigating patients with cervical masses should be aware that schwannomas need to be considered in the differential diagnosis of focal 99mTc-sestamibi uptake in the neck region.

UNASSIGNED: This study investigates the new combined parameters of 99mTc-DTPA orbital single-photon emission computed tomography/computed tomography (SPECT/CT) for the evaluation of Graves\' orbitopathy (GO) activity.
UNASSIGNED: A retrospective analysis was performed on 41 patients. All the patients undergone the 99mTc-DTPA orbital SPECT/CT and were categorized into active and inactive group based on the standard combined by the clinical active score (CAS), magnet resonance imaging (MRI) and/or follow-up results. Quantitative parameters of lacrimal gland (LG) including the protruding degree of lacrimal gland herniation (LGH) and uptake ratios (URs) of region of interest (ROI) drawn on lacrimal gland and occipital bone. SPECT/CT reading results were based on visual analysis. Parameters were compared between the two groups and the diagnostic value on discrimination of GO activity was also evaluated.
UNASSIGNED: All parameters of SPECT/CT for active GO groups were significantly higher than those of the inactive groups (p<.05). There were notable linear positive correlations between the assumption standard and readings as well as combination models 2 and 3 (r = .794, r = .772, r = .760, respectively). ROC analysis indicated that model 2 provided the highest diagnostic performance, exhibiting an area under the curve (AUC) of .947, a sensitivity of 92.7%, and a specificity of 88.6%.
UNASSIGNED: The combined use of SPECT/CT reading results and DTPA uptake parameters of LG offers a more objective and precise evaluation of active GO. This study further recommends 99mTc-DTPA SPECT/CT might be serving as a supplementary beneficial approach for CAS in evaluating GO activity.

BACKGROUND: Planar lymphoscintigraphy (PL) is commonly used in mapping before sentinel lymph node biopsy (SLNB) for invasive cutaneous melanoma. Recently, single-photon emission computed tomography (SPECT)/ computed tomography (CT) has been utilized, in addition to PL, for detailed anatomic information and detection of sentinel lymph nodes (SLNs) outside of the primary nodal basin in truncal and head and neck melanoma. Following a protocol change due to COVID-19, our institution began routinely obtaining both PL and SPECT-CT imaging for all melanoma SLN mapping. We hypothesized that SPECT-CT is associated with higher instances of SLNBs from \"nontraditional\" nodal basins (NTNB) for extremity melanomas.
METHODS: Patients with extremity melanoma (2017-2022) who underwent SLNB were grouped into SPECT-CT with PL versus PL alone. Outcomes were total SLNs removed, + or-SLN status, total NTNB sampled, and postoperative complication rate. Poisson regression and logistic regression models were used to assess association of SPECT-CT with patient outcomes.
RESULTS: Of 380 patients with extremity melanoma, 42.11% had SPECT-CT. There were no differences between the groups with regards to age at diagnosis or sex. From 2020 to 2022, all patients underwent SPECT-CT. SPECT-CT was associated with increased odds of SLNB from an NTNB, (odds ratio = 2.39 [95% confidence interval: 1.25-4.67]). There was no difference in odds of number of SLNs sampled, SLN positivity rate, or postoperative complication rate with SPECT-CT.
CONCLUSIONS: Routine SPECT-CT was associated with higher incidence of SLNB in NTNB but did not increase number of SLNs removed or SLN positivity rate. The added value of routine SPECT-CT in cutaneous melanoma of the extremities remains to be defined.

UNASSIGNED: The salivagram was first described to detect possible lung aspiration in infants or young children. Its original protocol required dynamic imaging for 60 minutes, which has high sensitivity. The purpose of this retrospective investigation was to determine whether a shortened period of image acquisition can be adopted without significantly reducing the sensitivity of the test in detecting aspiration.
UNASSIGNED: The current salivagram protocol in our hospital requires 60 minutes of dynamic imaging. The images of a total of 398 patients (ages 1 month to 9 years old) with positive salivagrams were analyzed. The entire 60-minute dynamic images were divided into 6 periods, 10 minutes/period. The time of the onset of abnormal activity in the bronchi, which was evidence of aspiration in each patient, was recorded and assigned to the corresponding period.
UNASSIGNED: Among all 398 patients with evidence of aspiration, tracheobronchial tree activity could be seen in the first 10 minutes of the dynamic imaging in 184 of them (46.2%, 184/398). The onset of the bronchial activity was seen between 10 and 20 minutes in 177 patients (44.5%, 177/398). A total of 35 patients (8.8%, 35/398) had the onset of abnormal tracheobronchial tree activity in the 3rd period between 20 and 30 minutes. During the 4th period between 30 and 40 minutes, the onset of the aspiration occurred in only 2 patients (0.5%, 2/398). All patients had the onset of aspiration in the first 40 minutes of the dynamic imaging.
UNASSIGNED: The originally described 60-minute dynamic imaging protocol of the salivagram can be safely shortened to 40 or even 30 minutes without a significantly decreased chance of detecting aspiration. Prolonged imaging is unnecessary.

When visualizing biological activity at nonunion sites by the radioisotopes, gamma rays are more attenuated if metal implants are placed in the bone. However, the effects of various implant types and their placement on gamma ray attenuation in quantitative evaluation remain unknown. To elucidate these effects, we created a phantom that simulated the nonunion of the femur in this study. The count of gamma rays was measured by single-photon emission computed tomography/computed tomography (SPECT/CT) while considering CT-based attenuation correction (CTAC), metal implant placement, type (intramedullary nail or plate), and position. The count differed significantly with and without CTAC and with and without implants (both types) under CTAC. Significantly different counts were observed between the intramedullary nail and plate placed contralaterally to the lesion (i.e., non-lesion side). No significant difference was observed between the intramedullary nail and plate on the lesion side or between plates on the non-lesion and lesion sides. The measured standardized uptake value (SUV) was closer to the true SUV with CTAC than without. Moreover, the count was higher with implants than without. However, even with implants, it was lower than the actual count, indicating the absence of overcorrection. Implant type and position do not seem to influence the count.

Objective: To investigate single-photon emission computed tomography/computed tomography (SPECT/CT) for assessing inflammation in the extraocular muscles (EOMs) and predicting the therapeutic efficacy of periocular glucocorticoid therapy (PGT) for Grave\'s ophthalmopathy (GO). Materials and Methods: A total of 412 eyes from 206 patients with GO referred for 99mTc-DTPA orbital SPECT/CT were enrolled. Fourteen age- and gender-matched healthy controls (28 eyes) were included. The thickness and uptake ratio (UR) of four EOMs were derived from SPECT/CT. Eighty-six eyes from patients with GO patients received PGT. Changes in SPECT/CT parameters were evaluated between the pre- and post-treatment. Results: 195 eyes and 217 eyes were classified as active and inactive stages by clinical activity score (CAS). Values of the thickness and UR of each EOM, Tmax, and Umax were all significantly higher in the active GO than in the inactive GO and controls (p < 0.01). Among the 86 eyes (48 GO patients) included in the efficacy analysis, 56 eyes and 30 eyes were classified as responders and non-responders. Values of thicknesses and UR of each EOM, the maximum thickness (Tmax), and the maximum UR (Umax) all dropped following PGT in the responders (p < 0.01). Logistic regression analysis identified the Umax as an independent predictor for the responders (p < 0.01). Moreover, the Umax demonstrated incremental predictive value over clinical characters and CAS, as evidenced by the improved area under the curve (0.85 vs. 0.78) and global chi-square (34.12 vs. 18.1). Conclusion: 99mTc-DTPA SPECT/CT has the potential to assess inflammatory activity by detecting the involvement of EOMs in GO. Pre-treatment UR provides independent and incremental values for the prediction of PGT treatment response.

Breast cancer liver metastasis (BCLM) is considered to occur by hematogenous spread of primary breast cancer cells. We herein present a case of lymphatic BCLM that was confirmed by preoperative imaging for sentinel lymph node biopsy (SLNB). A woman in her early 70s was diagnosed with clinical stage T2N0M0 invasive lobular cancer of the left breast. She underwent mastectomy with SLNB. Preoperative lymphoscintigraphy showed intense accumulation of isotope in the upper abdomen, corresponding to segment IV of the liver on single-photon emission computed tomography/computed tomography (SPECT/CT). However, no abnormalities were detected on magnetic resonance imaging. At 2.5 years postoperatively, the patient\'s serum CA15-3 concentration was elevated, and positron emission tomography/computed tomography (PET/CT) showed a solitary liver metastasis. The PET/CT findings were similar to the SPECT/CT findings obtained 2.5 years earlier, indicating that the BCLM had developed lymphatically. To the best of our knowledge, this is the first case report of lymphatic BCLM proven by imaging examination.

OBJECTIVE: Hyperfunctioning parathyroid lesions require surgical resection. 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) plays an important role in the diagnosis of parathyroid lesions. Some nodular goiters have a higher uptake of 99mTc-MIBI, which is difficult to distinguish from hyperfunctioning parathyroid lesions. This study aims to explore the value of 99mTc-MIBI SPECT/CT in the differential diagnosis of parathyroid lesions and nodular goiter.
METHODS: This study was a retrospective analysis. A total of 68 patients who were diagnosed as parathyroid lesions by 99mTc-MIBI SPECT/CT were enrolled, with a total of 81 lesions. According to the results of pathological examination after surgical resection, the lesions were divided into a parathyroid lesion group (n=69) and a nodular goiter group (n=12). The target maximum radioactivity count (Tmax) of all lesions was measured. The mean radioactivity count of the aortic arch was used as the background mean radioactivity count (Bmean), and the ratio of the Tmax to Bmean was calculated. The difference in Tmax/Bmean between the 2 groups was compared. The minimum, mean, and maximum of CT density in the lesion were measured. The difference of CT density between the 2 groups was compared. The receiver operating characteristic (ROC) curve of patients with parathyroid lesions and patients with nodular goiter was drawn, and the diagnostic efficacy of each CT density value was evaluated.
RESULTS: The 99mTc-MIBI radioactive uptake in parathyroid lesions and nodular goiter lesions was significantly concentrated. The CT density values of the 2 lesions were lower than normal thyroid tissue, and the boundary between the 2 lesions and the thyroid was clear or blurred. There was no significant difference in Tmax/Bmean between the 2 groups (P=0.221). The differences in the minimum, mean and maximum of CT density between the 2 groups were statistically significant (all P<0.05). The diagnostic efficiency of maximum of CT density was the best, area under the ROC curve was 0.894 (P<0.001), the cut-off was 91 HU, the sensitivity was 83.3%, and the specificity was 94.2%.
CONCLUSIONS: The degree of 99mTc-MIBI radiation uptake in the focus has limited value in differentiating parathyroid lesions from nodular goiter, and the maximum density of CT possesses high diagnostic efficiency.
目的: 功能亢进的甲状旁腺病灶需手术切除，99m锝-甲氧基异丁基异腈(99mTc-methoxyisobutylisonitrile，99mTc-MIBI)单光子发射计算机体层摄影/计算机体层摄影(single-photon emission computed tomography/computed tomography，SPECT/CT)在甲状旁腺病灶定位诊断中起重要作用，而部分结节性甲状腺肿摄取99mTc-MIBI较高，与功能亢进的甲状旁腺病灶难以鉴别。本研究旨在探讨99mTc-MIBI SPECT/CT在甲状旁腺病灶与结节性甲状腺肿鉴别诊断中的价值。方法: 回顾性分析通过99mTc-MIBI SPECT/CT拟诊为甲状旁腺病灶的68例患者，共计81个病灶。根据手术切除后病理检查结果将病灶分为甲状旁腺病灶组(69个)和结节性甲状腺肿组(12个)。测量所有病灶的放射性计数最大值(target maximum radioactivity count，Tmax)，以主动脉弓平均放射性计数作为本底放射性计数平均值(background mean radioactivity count，Bmean)，并计算二者的比值(Tmax/Bmean)，比较2组间Tmax/Bmean的差异；测量病灶CT密度最小值、平均值和最大值，比较2组间各CT密度值的差异；绘制甲状旁腺病灶患者与结节性甲状腺肿患者受试者操作特征(receiver operating characteristic，ROC)曲线，评估各CT密度值的诊断效能。结果: 甲状旁腺病灶与结节性甲状腺肿病灶99mTc-MIBI放射性摄取明显浓聚；2种病灶的CT密度值均低于正常甲状腺组织，2种病灶与甲状腺的分界均可表现为清晰或模糊2种情况。2组Tmax/Bmean值比较差异无统计学意义(P=0.221)。2组CT密度最小值、平均值及最大值比较，差异均有统计学意义(均P<0.05)。CT密度最大值的诊断效能最优，曲线下面积(area under the curve，AUC)为0.894(P<0.001)，其阈值为91 HU，敏感度为83.3%，特异度为94.2%。结论: 病灶99mTc-MIBI放射性摄取程度对甲状旁腺病灶与结节性甲状腺肿的鉴别价值有限，病灶CT密度最大值具有较高诊断效能。.

A 45-year-old male with a history of trauma was referred to the department of nuclear medicine to identify site of a biliary leak, which could not be identified in ultrasound and exploratory laparotomy. Contrast-enhanced computed tomography (CT) was able to identify lacerations in the right lobe of the liver, but the extent of injury to the biliary pathways and vessels was unclear. 99mTc-HIDA scintigraphy with single-photon emission CT/CT was not only able to identify the site of leak but also the extent of infarcted area.