Comparison of Neck Ultrasonography, Dual Phase 99mTc-Sestamibi with early SPECT-CT & 18F-Fluorocholine PET-CT as First Line Imaging in Patients with Primary Hyperparathyroidism.

Introduction: Successful surgical treatment for primary hyperparathyroidism requires accurate localization of abnormal parathyroid tissue in terms of location and number. Imaging is important for localizing the parathyroid adenoma, and there has been significant interest in 18F-fluorocholine (FCH) positron emission tomography/computed tomography (PET/CT) for this purpose. Aim: This study attempted to ascertain the utility of 18F-FCH PET/CT as a first-line investigation in preoperative localization of abnormal parathyroid tissue in primary hyperparathyroidism, in comparison with 99mTc-sestamibi dual-phase scintigraphy with early single-photon emission computed tomography (SPECT)/CT and neck ultrasonography. Materials and Methods: Fifty-five patients with biochemical features of primary hyperparathyroidism were enrolled in this study. They underwent neck ultrasonography, 99mTc-sestamibi dual-phase scintigraphy with early SPECT/CT, and 18F-FCH PET/CT for localization of parathyroid lesions. Thirty-three patients underwent surgical resection of the detected lesions. For two patients, clinical and biochemical follow-up was used as a gold standard. Results: A total of 40 lesions were resected in the 33 patients who underwent surgery. A further two lesions were localized in two patients with clinical and biochemical follow-up as the gold standard. Of these 42 lesions, 41 were detected in preoperative imaging and 1 lesion was noted intraoperatively and resected. 41/42 lesions were detected by 18F-FCH PET/CT (detection rate: 97.6%), 33/42 by 99mTc-sestamibi dual-phase scintigraphy with early SPECT/CT (detection rate: 78.5%), and 30/42 by neck ultrasonography (detection rate: 71.4%). Conclusion: Detection rates on 18F-FCH PET/CT were superior to both 99mTc-sestamibi dual-phase scintigraphy with early SPECT/CT and neck ultrasonography in preoperative localization of parathyroid lesions in patients with primary hyperparathyroidism.

Importancia de los radiotrazadores MDP, DTPA, MIBI marcados con Tc99m en diagnóstico de medicina nuclear / Importance of Tc99m-labeled MDP, DTPA, MIBI radiotracers in nuclear medicine diagnostics / Importância dos radiotraçadores MDP, DTPA e MIBI marcados com Tc99m em diagnósticos de medicina nuclear

La medicina nuclear utiliza radiofármacos, conocidos como radiotrazadores, para evaluar la función y el metabolismo de órganos y sistemas del cuerpo. Objetivo. Examinar la relevancia de los radiotrazadores MDP, DTPA y MIBI, marcados con tecnecio-99m (Tc99m), en el diagnóstico en medicina nuclear. Metodología. Se siguió el método PRISMA para identificar estudios publicados entre 2010 y 2022. Las bases de datos consultadas incluyeron Dialnet, Elsevier, Research, Redalyc, PubMed, Google Académico y Scielo. Se utilizaron descriptores específicos como "radiotrazadores Tc99m", "MDP", "DTPA", "MIBI", y "medicina nuclear", centrando la búsqueda en diagnóstico y excluyendo propósitos terapéuticos. Resultados. De 14 estudios analizados, se observó una predominancia en investigaciones sobre radiotrazadores MDP y MIBI marcados con Tc99m, enfocándose en diagnósticos relacionados con lesiones paratiroideas, hiperparatiroidismo, enfermedades esqueléticas, enfermedad arterial coronaria y perfusión miocárdica. Conclusiones. Los radiotrazadores MDP, DTPA y MIBI marcados con Tc99m demuestran eficacia en diversas aplicaciones diagnósticas, incluyendo la localización de adenomas paratiroideos y la detección de condiciones como el mieloma múltiple. A pesar de sus beneficios, es crucial continuar investigando y desarrollando nuevos radiofármacos para expandir su utilidad clínica y mejorar aún más la atención médica en el campo de la medicina nuclear.

Nuclear medicine uses radiopharmaceuticals, known as radiotracers, to assess the function and metabolism of organs and body systems. Objective. To examine the relevance of technetium-99m (Tc99m)-labeled MDP, DTPA, and MIBI radiotracers in nuclear medicine diagnostics. Methodology. The PRISMA method was followed to identify studies published between 2010 and 2022. The databases consulted included Dialnet, Elsevier, Research, Redalyc, PubMed, Google Scholar and Scielo. Specific descriptors such as "Tc99m radiotracers", "MDP", "DTPA", "MIBI", and "nuclear medicine" were used, focusing the search on diagnosis and excluding therapeutic purposes. Results. Of 14 studies analyzed, there was a predominance of research on Tc99m-labeled MDP and MIBI radiotracers, focusing on diagnoses related to parathyroid lesions, hyperparathyroidism, skeletal diseases, coronary artery disease, and myocardial perfusion. Conclusions. Tc99m-labeled MDP, DTPA, and MIBI radiotracers demonstrate efficacy in a variety of diagnostic applications, including localization of parathyroid adenomas and detection of conditions such as multiple myeloma. Despite their benefits, it is crucial to continue researching and developing new radiopharmaceuticals to expand their clinical utility and further improve medical care in the field of nuclear medicine.

A medicina nuclear utiliza radiofármacos, conhecidos como radiotraçadores, para avaliar a função e o metabolismo de órgãos e sistemas corporais. Objetivo. Examinar a importância dos radiotraçadores MDP, DTPA e MIBI, marcados com tecnécio-99m (Tc99m), em diagnósticos de medicina nuclear. Metodologia. O método PRISMA foi usado para identificar estudos publicados entre 2010 e 2022. Os bancos de dados consultados incluíram Dialnet, Elsevier, Research, Redalyc, PubMed, Google Scholar e Scielo. Foram utilizados descritores específicos como "radiotraçadores Tc99m", "MDP", "DTPA", "MIBI" e "medicina nuclear", concentrando a busca em fins diagnósticos e excluindo fins terapêuticos. Resultados. Dos 14 estudos analisados, houve predomínio de pesquisas com os radiotraçadores MDP e MIBI marcados com Tc99m, com foco em diagnósticos relacionados a lesões da paratireoide, hiperparatireoidismo, doenças esqueléticas, doença arterial coronariana e perfusão miocárdica. Conclusões. Os radiotraçadores MDP, DTPA e MIBI marcados com Tc99m demonstram eficácia em uma variedade de aplicações diagnósticas, incluindo a localização de adenomas de paratireoide e a detecção de doenças como o mieloma múltiplo. Apesar de seus benefícios, é fundamental continuar a pesquisa e o desenvolvimento de novos radiofármacos para expandir sua utilidade clínica e melhorar ainda mais o atendimento médico no campo da medicina nuclear.

Parathyroid fine-needle aspiration with parathyroid hormone washout as a preoperative localisation of parathyroid adenoma-A retrospective study.

OBJECTIVE: The use of parathyroid lesion aspiration in preoperative adenoma localisation is controversial. Concerns have been raised regarding both immediate safety (hematoma, infection, alterations on a subsequent histologic preparate) and long-term safety (seeding). We aimed to evaluate the short- and long-term safety, and the efficacy, of parathyroid fine-needle aspiration with parathyroid hormone washout as a localisation modality of parathyroid adenoma in patients with primary hyperparathyroidism. DESIGN: A retrospective study. PATIENTS: The sample comprised 29 patients with primary hyperparathyroidism who underwent minimally invasive parathyroidectomy at a tertiary referral centre, following localisation with parathyroid hormone washout. MEASUREMENTS: We reviewed all parathyroid hormone washout procedures performed during 2011-2021. Clinical, biochemical, and imaging information; and cytology, surgery, and pathology reports were extracted from electronic medical records. RESULTS: Parathyroid hormone levels from the needle wash were 2.1-112.5 times the upper limit of the serum norm. Other than mild neck discomfort, no immediate procedure complications were documented. Fibrotic changes and necrosis were reported in two patients, with no effect on the final pathologic diagnosis or surgery course. No long-term complications (seeding, or parathyromatosis) were found. A total of 26 (90%) patients who were operated following a positive parathyroid hormone washout result were normocalcemic at the end of a mean 38.1-month follow-up period. CONCLUSIONS: Parathyroid fine-needle aspiration with parathyroid hormone washout was accurate. Immediate, surgical, or delayed complications were not demonstrated in our series. This approach might be considered for selected patients.

Myocardial Flow Assessment After Heart Transplantation Using Dynamic Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography With 201Tl and 99mTc Tracers and Validated by 13N-NH3 Positron Emission Tomography.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is an obliterative and diffuse form of vasculopathy and is the most common cause of long-term cardiovascular mortality in heart transplant patients. This study aimed to investigate the diagnostic performance of 99mTc and 201Tl tracers in the assessment of CAV using cadmium-zinc-telluride (CZT) single-photon emission computed tomography (SPECT) for myocardial blood flow (MBF) and myocardial flow reserve (MFR) quantification, which was further validated using 13 N-NH3 positron emission tomography (PET). METHODS: Thirty-eight patients with prior heart transplantation who underwent CZT SPECT and 13 N-NH3 PET dynamic scans were included in this study. CZT SPECT with 99mTc-sestamibi was used in the first 19 patients and 201Tl-chloride for the remaining patients. To determine the diagnostic accuracy of angiographically defined moderate-to-severe CAV, the analysis included patients who underwent angiographic examinations within 1 year of their second scan. RESULTS: There were no significant differences in the patient characteristics between the 201Tl and 99mTc tracer groups. Both 201Tl and 99mTc CZT SPECT-derived stress MBF and MFR values globally and in 3 coronary territories showed good correlations with 13 N-NH3 PET. The 201Tl and 99mTc cohorts did not differ significantly in the correlation coefficients of CZT SPECT versus PET for MBF and MFR, except for stress MBF (201Tl:0.95 versus 99mTc:0.80, P=0.03). 201Tl and 99mTc CZT SPECT were satisfactory for detecting PET MFR <2.0 (201Tl area under the curve, 0.92 [0.71-0.99], 99mTc area under the curve, 0.87 [0.64-0.97]) and angiographically defined moderate-to-severe CAV, and CZT SPECT results were comparable to that of 13 N-NH3 PET (CZT area under the curve, 0.90 [0.70-0.99], PET area under the curve, 0.86 [0.64-0.97]). CONCLUSIONS: This small study suggests that CZT SPECT using 201Tl and 99mTc tracers showed comparable MBF and MFR, and the results correlated well with those of 13 N-NH3 PET. Hence, CZT SPECT with 201Tl or 99mTc tracers can be used to detect moderate-to-severe CAV in patients with prior heart transplantation. However, validation using larger studies is warranted.

Comparison of biochemical markers and technetium 99m methoxyisobutylisonitrile imaging in primary and secondary hyperparathyroidism.

Objective: To investigate the differences in biochemical marker levels and the extent of lesion visualization on technetium 99m methoxyisobutylisonitrile (99mTc-MIBI) imaging between primary hyperparathyroidism (PHPT) and secondary hyperparathyroidism (SHPT). Methods: Nineteen patients with PHPT and 14 patients with SHPT were enrolled in the study, all of whom underwent routine 99mTc-MIBI dual-phase planar imaging, single-photon emission computed tomography combined with computed tomography (SPECT/CT fusion) imaging, and serum biochemical and hormonal investigations prior to surgery. The target-to-non-target (T/NT) ratios were calculated based on images from the early and delayed phases of 99mTc-MIBI planar imaging and also based on SPECT/CT fusion imaging. The volume of the parathyroid glands was measured following their excision. Results: A total of 62 parathyroid glands were removed: 14 parathyroid adenomas and five parathyroid carcinomas in PHPT patients; and 18 parathyroid adenomas, 17 parathyroid hyperplasia lesions, and eight instances of nodular hyperplasia with adenoma in SHPT patients. The median volume of the lesions in PHPT and SHPT was 1.69 cm3 and 0.52 cm3 respectively, and the difference between them was statistically significant (P = 0.001). The median T/NT ratios calculated at the early phase of 99mTc-MIBI planar imaging, the delayed phase of 99mTc-MIBI planar imaging, and the subsequent SPECT/CT fusion imaging were 1.51, 1.34, and 2.75, respectively, in PHPT, and 1.46, 1.30, and 1.38, in SHPT, respectively. The T/NT ratio difference between PHPT and SHPT on the SPECT/CT fusion imaging was statistically significant (P = 0.002). The histopathology subtypes of the lesions were associated with significant differences in two areas: the T/NT ratios on the SPECT/CT fusion imaging and the volume of the lesions (P=0.002, P<0.001). Conclusion: The proportion of positive findings on 99mTc-MIBI dual-phase planar imaging and the T/NT ratios of 99mTc-MIBI SPECT/CT fusion imaging were higher in PHPT than in SHPT. The volume of parathyroid lesions in SHPT was smaller than in PHPT.

Application of 99Tc m-MIBI SPECT/CT imaging in patients with primary cervical dystonia / 中华核医学与分子影像杂志

Objective:To evaluate the value of 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT/CT imaging for the identification of dystonic muscles in patients with primary cervical dystonia (PCD). Methods:A total of 10 patients with PCD (3 males, 7 females, age (47.3±9.9) years) and 10 healthy subjects (4 males, 6 females, age (43.5±9.4) years; control group) between August 2019 and October 2021 in China-Japan Friendship Hospital were enrolled prospectively. All subjects underwent 99Tc m-MIBI SPECT/CT scan. The SUV max of 8 bilateral representative muscles, including rectus capitis posterior major, obliquus capitis inferior, splenius capitis, semispinalis, sternocleidomastoid, trapezius, musculus scalenus muscle and levator scapulae were evaluated in control group. In PCD group, muscles with abnormal uptake were determined. ROI was drawn and SUV max was measured. Independent-sample t test was used to analyze the differences of SUV max between normal and abnormal muscles. The detecting rates of neck MRI and SPECT/CT for abnormal muscles were analyzed by χ2 test. Results:Normal muscles of healthy subjects showed mild symmetrical radioactivity distribution, with the SUV max of 1.10±0.19. A total of 60 muscles with abnormal uptake in 10 patients were found, including 7 rectus capitis posterior major, 10 obliquus capitis inferior, 8 splenius capitis, 8 semispinalis, 10 sternocleidomastoid, 5 trapezius, 3 musculus scalenus muscle and 9 levator scapulae. The SUV max of muscles with abnormal uptake was 1.81±0.43, which was higher than that of normal muscles ( t=17.05, P<0.001). Only 30 pieces abnormal hypertrophy muscle were found by neck MRI, and the detecting rate was much lower than that of SPECT/CT (18.75%(30/160) vs 37.50%(60/160); χ2=28.03, P<0.001). Conclusion:99Tc m-MIBI SPECT/CT may be a useful method for identifying dystonic muscles and a guide to precision therapy in patients with PCD.

Sestamibi scan in renal parathyroidectomy: a worthwhile preoperative exam? / Cintilografia com sestamibi na paratireoidectomia renal: um exame pré‐operatório que vale a pena?

Abstract Introduction Surgical treatment of hyperparathyroidism related to chronic kidney disease is a real challenge for Brazilian public health care. High cost medications and long waiting lines to perform preoperative exams, especially technetium Tc 99m Sestamibi (MIBI) are some of the reasons. Despite the reality that the aid of localization exams are questionable in this scenario, doctors are too apprehensive in performing surgery without it. Objective The study aimed at evaluating the efficacy of surgery for renal hyperparathyroidism without preoperative MIBI. Methods A total of 114 patients were surgically treated. Total parathyroidectomy with autotransplantation and subtotal parathyroidectomy were carried out without preoperative MIBI. Results and conclusion Among the 114 patients undergoing surgery, 37 had secondary hyperparathyroidism in dialysis replacement, and 77 patients had post-renal transplant persistent disease. We were successful in 107 cases with only 7 failures (93.8% of success rate). Among these failures, only one parathyroid gland was not found in 4 cases, 2 parathyroid glands were not found in 2 cases and in 1 patient the 4 glands were found but this patient remained hypercalcemic and a postoperative diagnosis of supernumerary parathyroid gland was made. Surgery for treatment of renal hyperparathyroidism proved to be an effective (93.8%) and reproductible procedure, even without MIBI.

Resumo Introdução O tratamento cirúrgico do hiperparatireoidismo relacionado à doença renal crônica é um verdadeiro desafio para a saúde pública brasileira. Medicamentos de alto custo e longas filas de espera para exames pré‐operatórios, principalmente a cintilografia com tecnécio Tc‐99m Sestamibi, MIBI, são alguns dos motivos. Apesar da contribuição de exames de localização ser questionável nesse cenário, os médicos ficam muito apreensivos por fazer uma cirurgia sem ele. Objetivo Avaliar a eficácia da cirurgia para hiperparatireoidismo renal sem o MIBI pré‐operatório. Método Foram tratados cirurgicamente 114 pacientes. A paratireoidectomia total com autotransplante e a paratireoidectomia subtotal foram feitas sem MIBI pré‐operatório. Resultados e conclusão Entre os 114 pacientes submetidos à cirurgia, 37 apresentavam hiperparatireoidismo secundário em reposição dialítica e 77 doença persistente pós‐transplante renal. Tivemos sucesso em 107 casos, com apenas 7 falhas (93,8% de taxa de sucesso). Entre essas falhas, uma glândula paratireoide não foi encontrada em 4 casos, 2 glândulas paratireoides não foram encontradas em 2 casos e em um paciente as 4 glândulas foram encontradas, mas ele permaneceu hipercalcêmico com diagnóstico pós‐operatório de glândula paratireoide supranumerária. A cirurgia para tratamento do hiperparatireoidismo renal mostrou‐se um procedimento eficaz (93,8%) e reprodutível mesmo sem MIBI.

Fluorine-18 Fluorocholine Positron Emission Tomography/Computed Tomography in Primary Hyperparathyroidism: A Case Report and Review of Literature.

Positron emission tomography (PET) tracers (Fluorine-18 Fluorocholine [18F-Fluorocholine] and Carbon-11 Choline [11C-Choline]) have been widely used with promising accuracy in detecting abnormal parathyroids, being crucial for an effective and safe minimally invasive parathyroidectomy. We report a case of a 72-year-old woman with a long-term personal history of osteoporosis and recurrent nephrolithiasis with the need for invasive interventions. Primary hyperparathyroidism was biochemically assumed, although localization of the hyperfunctioning parathyroid had been challenging since cervical ultrasound and technetium-99m sestamibi scintigraphy were negative/equivocal. An 18F-Fluorocholine positron emission tomography/computed tomography (PET/CT) was performed, having identified a small cervical nodule with increased tracer uptake, compatible with a right parathyroid adenoma. After its removal, the patient went into clinical and biochemical remission. 18F-Fluorocholine PET/CT allowed an effective and safe parathyroidectomy as conventional imaging modalities were inaccurate in detecting the abnormal parathyroid, in this patient with serious hyperparathyroidism-related complications.

Sestamibi scan in renal parathyroidectomy: a worthwhile preoperative exam?

INTRODUCTION: Surgical treatment of hyperparathyroidism related to chronic kidney disease is a real challenge for Brazilian public health care. High cost medications and long waiting lines to perform preoperative exams, especially technetium Tc 99m Sestamibi (MIBI) are some of the reasons. Despite the reality that the aid of localization exams are questionable in this scenario, doctors are too apprehensive in performing surgery without it. OBJECTIVE: The study aimed at evaluating the efficacy of surgery for renal hyperparathyroidism without preoperative MIBI. METHODS: A total of 114 patients were surgically treated. Total parathyroidectomy with autotransplantation and subtotal parathyroidectomy were carried out without preoperative MIBI. RESULTS AND CONCLUSION: Among the 114 patients undergoing surgery, 37 had secondary hyperparathyroidism in dialysis replacement, and 77 patients had post-renal transplant persistent disease. We were successful in 107 cases with only 7 failures (93.8% of success rate). Among these failures, only one parathyroid gland was not found in 4 cases, 2 parathyroid glands were not found in 2 cases and in 1 patient the 4 glands were found but this patient remained hypercalcemic and a postoperative diagnosis of supernumerary parathyroid gland was made. Surgery for treatment of renal hyperparathyroidism proved to be an effective (93.8%) and reproductible procedure, even without MIBI.

Comparison of IQ-SPECT and low energy high-resolution collimator SPECT in clinical application / 中华核医学与分子影像杂志

Objective:To investigate differences in cardiac function and perfusion parameters measured by IQ-SPECT and low energy high-resolution (LEHR)-SPECT, as well as effects of scattering correction (SC) and CT attenuation correction (AC) on myocardial perfusion imaging.Methods:From May 2020 to September 2020, 80 patients (58 males, 22 females, age (57±10) years) who underwent SPECT myocardial perfusion imaging were retrospectively enrolled in Fuwai Hospital. According to the standardized left ventricular end-diastolic diameter of body surface measured by two-dimensional echocardiography, patients were divided into 2 groups: A group ( n=34) with significantly enlarged left ventricle and B group ( n=46) with no significant enlargement of left ventricle. LEHR-SPECT and IQ-SPECT gated myocardial perfusion imaging were performed in all patients. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), summed rest score (SRS) and total perfusion defect (TPD) were measured. Parameters measured by two methods and differences before and after SC and AC were compared by using paired t test and Wilcoxon signed rank test. The correlation was analyzed by Pearson correlation or Spearman rank correlation analyses, and the consistency was analyzed by Bland-Altman analysis. Results:In A group, EDV, EF and SRS measured by IQ-SPECT were significantly lower than those assessed by LEHR-SPECT after SC and AC (EDV: (257±137) vs (276±154) ml, EF: (21±11)% vs (26±13)%, SRS: 17(6, 25) vs 18(8, 28); t values: -2.63, -7.46, z=-2.14, all P<0.05); all parameters measured by LEHR-SPECT and IQ-SPECT had well correlation ( r values: 0.965, 0.969, 0.967, rs values: 0.920, 0.960, all P<0.001) and consistency. In B group, EDV and EF measured by IQ-SPECT were significantly lower than those assessed by LEHR-SPECT after SC and AC (EDV: (96±40) vs (107±39) ml, EF: (46±15)% vs (54±16)%; t values: -6.23, -10.71, both P=0.001); SRS and TPD measured by IQ-SPECT after SC and AC were significantly lower than non-SC and non-AC (SRS: 2(1, 4) vs 5(3, 11), TPD: (3%(1%, 5%) vs 7%(3%, 12%); z values: -4.11, -4.16, both P<0.001); all parameters measured by LEHR-SPECT and IQ-SPECT had well correlation ( r values: 0.956, 0.978, 0.958, rs values: 0.926, 0.944, all P<0.001) and consistency. Conclusions:There are good correlation and consistency of left ventricular function and myocardial perfusion parameters acquired by IQ-SPECT and LEHR-SPECT. Moreover, IQ-SPECT is able to shorten acquisition time, resulting in great potential in clinical application.

Serially evaluation of changes in myocardial perfusion, hibernation myocardium and left ventricular function in the development of chronic coronary artery occlusion by gated SPECT perfusion and gated PET imaging in pigs / 中华核医学与分子影像杂志

Objective:To serially characterize the myocardial perfusion, myocardial hibernation and left ventricular (LV) function as well as LV remodeling in progressive coronary artery stenosis in Chinese mini-pigs.Methods:In 8 Chinese mini-pigs (5 males, 3 females; age: 10 months), chronic progression of coronary stenosis and finally occlusion was established using Ameroid constrictor implantation at the 1 cm below the bifurcation of the first diagonal branch of the left anterior descending (LAD) artery. Serial gated 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT/CT, gated 18F-FDG PET/CT imaging and coronary angiography (CAG) were performed before surgery and at the 1st, 4th and 8th week after surgery. Longitudinally, total perfusion defect (TPD), LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), summed motion score (SMS), summed thickening score (STS) and hibernating myocardium (HM) were analyzed. Repeated measures analysis of variance, Kruskal-Wallis rank sum test and Bonferroni correction method were used to analyze data. Results:One mini-pig died of infection after the Ameroid constrictor implantation. In the remaining 7 mini-pigs, TPD was progressively increased with time prolonged (0, 12.0%(0, 33.0%), (41.1±23.7)% and (49.3±24.5)%; H=17.03, P=0.001); Compared with HM before the surgery (100%), HM was gradually reduced from the 1st (21.0%(6.0%, 100%)) to the 4th (18.0%(3.0%, 33.0%)) week after surgery, and then increased to the 8th week after surgery ((23.0±15.4)%; H=13.09, P=0.004), but there was no significant difference between the 1st and 4th week, or between the 4th and 8th week after surgery (both P>0.05 (Bonferroni correction method)). Accordingly, LVEF gradually decreased ((73.7±8.4)%, (63.7±19.1)%, (53.7±14.6)% and (49.9±15.4)%; F=6.22, P=0.004). LVEDV (9.0(6.0, 21.0), (31.4±16.3), (32.9±17.4) and (36.4±17.5) ml; H=8.58, P=0.035)and LVESV ((3.8±3.2), (15.9±15.3), 12.0(10.0, 17.0)and (19.3±10.9) ml; H=10.51, P=0.015) gradually increased. SMS and STS continuously increased as well ( H values: 16.49, 13.33, P values: 0.001, 0.004). Conclusions:With the progression of coronary artery stenosis to occlusion, myocardial perfusion is gradually decreased, while the global and regional LV function, LV remodeling are gradually aggravated, and HM is gradually reduced. After the chronic coronary artery occlusion, myocardial perfusion has a trend to be improved and HM is gradually recovered.

Assessment of left ventricular diastolic dyssynchrony and its influencing factors early after acute myocardial infarction by SPECT gated myocardial perfusion imaging: an experimental study / 中华核医学与分子影像杂志

Objective:To evaluate the left ventricular diastolic dyssynchrony (LVDD) and its influencing factors early after acute myocardial infarction (AMI) using phase analysis of SPECT gated myocardial perfusion imaging (GMPI).Methods:Bama miniature swines ( n=16) were subjected to establish AMI models. GMPI was performed before and 1 d after AMI to obtain the extent of myocardial perfusion defect (Extent, %) and left ventricular systolic dyssynchrony (LVSD)/LVDD parameters, namely the phase histogram bandwidth (PBW) and phase standard deviation (PSD). Meanwhile, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the ratio of early to late peak mitral diastolic flow (E/A) were obtained by echocardiography. Independent-sample t test, paired t test and Pearson correlation analysis were used to analyze the data. Results:Sixteen AMI swines were successfully created. Compared to baseline, Extent, LVEDV and LVESV significantly increased on 1 d after AMI ( t values: -11.14, -4.55, -6.12, all P<0.001), while LVEF and E/A significantly decreased ( t values: 10.16, 2.18, P<0.001, P=0.046). GMPI showed that the LVDD parameters PBW and PSD increased significantly on 1 d after AMI when compared to those at baseline((142.25±72.06)° vs (33.06±8.98)°, (56.15±26.71)° vs (12.51±5.13)°; t values: -6.11, -6.60, both P<0.001). There were significant differences between LVSD parameters and LVDD parameters (PBW: (109.06±62.40)° vs (142.25±72.06)°, PSD: (44.40±25.61)° vs (56.15±26.71)°; t values: -2.73, -2.20, P values: 0.016, 0.044). LVDD parameters PBW, PSD were negatively correlated with E/A after AMI ( r values: -0.569, -0.566, P values: 0.021, 0.022), and positively correlated with the Extent ( r values: 0.717, 0.634, P values: 0.002, 0.008). The phase analysis of SPECT GMPI to evaluate LVDD showed good intra-observer and inter-observe reproducibility (intraclass correlation coefficient (ICC): 0.953-0.984, all P<0.001). Conclusions:LVDD occurs early on 1 d after AMI, and can reflect left ventricular diastolic dysfunction. The Extent is correlated with LVDD significantly. Phase analysis of SPECT GMPI is an accurate method to evaluate LVDD and left ventricular diastolic function.

Inter- and Intraobserver Repeatability of Myocardial Flow Reserve Values Determined with SPECT Study Using a Discovery NM530c Camera and Corridor 4DM Software.

BACKGROUND: Myocardial blood flow (MBF) and flow reserve (MFR) examination, especially useful in the diagnosis of multivessel coronary artery disease (CAD), can be assessed with a cadmium-zinc-telluride (CZT) SPECT gamma camera, as an alternative to the expensive and less available PET. However, study processing is not free from subjective factors. Therefore, this paper aims to evaluate intra- and interobserver repeatability of MBF and MFR values obtained by the same operator and two independent operators. METHODS: This study included 57 adult patients. MBF and MFR were assessed using a Discovery NM530c camera in a two-day, rest/dipyridamople protocol, using 99mTc-MIBI. Data were processed using Corridor4DM software, twice by one operator and once by another operator. RESULTS: The repeatability of the assessed values was quite good in the whole myocardium, LAD and LCX vascular territories, but was poor in the RCA territory. CONCLUSIONS: The poor repeatability of MBF and MFR in RCA vascular territory can be explained by poor automatic orientation of the heart axis during post-processing and a so-called "cardiac creep" phenomenon. Better automatic heart orientation and introduction of automatic motion correction is likely to drastically improve this repeatability. In the present state of the software, PET is better for patients requiring assessment of MFR in the RCA territory.

Mask-Related Motion Artifact on 99mTc-MIBI SPECT: Unexpected Pitfalls of SARS-CoV-2 Countermeasures.

A 61-year-old man was referred for myocardial perfusion scintigraphy (MPS) by an occupational physician to exclude coronary artery disease (CAD). The patient had a complete left bundle branch block (LBBB) that rendered the routine exercise stress test non-diagnostic, but otherwise had no history of heart diseases, good stress tolerance with no symptoms of angina, and no abnormalities in transthoracic echocardiogram, apart from contraction patterns typical for LBBB. Initial MPS, performed using technetium-labeled Sestamibi on a Discovery NM 530c camera equipped with solid-state semiconductor detectors, revealed a significant stress-induced ischemia that did not match the good overall condition of the patient. A motion detection procedure revealed significant heart motion in Z-axis during the stress study. Upon inquiry, the patient reported breathing difficulties caused by the mandatory mask, which slipped into an uncomfortable position during the study. Repeated acquisition, without motion artifacts, revealed no features of ischemia.

Radioactive Parathyroid Adenomas on Sestamibi Scans: Low Parathyroid Hormone Secretory Potential and Large Volume.

BACKGROUND: We investigated the clinical characteristics of parathyroid adenomas according to radioactivity on 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) in primary hyperparathyroidism (PHPT) patients. METHODS: The study included 217 patients diagnosed with PHPT from 2000 to 2019 at Seoul National University Hospital who underwent 99mTc-MIBI SPECT/CT scans. On SPECT/CT, the radioactivity of parathyroid adenomas was measured as the ratio of the mean radioactivity count of the parathyroid adenoma to that of the contralateral thyroid. RESULTS: Tumors were localized by MIBI scans in 190 patients (MIBI [+] group) and by ultrasound or parathyroid four-dimensional CT in 27 patients (MIBI [-] group). The mean age was 55 years, and mean body mass index was 23.4 kg/m2. Patients in the MIBI (+) group had higher parathyroid hormone (iPTH) and lower 25-hydroxy vitamin D levels than those in the MIBI (-) group (168.0 pg/mL [interquartile range, IQR, 111.0 to 250.7] vs. 134.7 pg/mL [IQR, 98.2 to 191.2], P=0.049; 15.4 ng/mL [IQR, 11.1 to 20.8] vs. 21.2 ng/mL [IQR, 13.9 to 24.8], P=0.012, respectively). Patients in the MIBI (+) group had larger tumor volumes, but lower iPTH/volume ratios than those in the MIBI (-) group (1,216.66 [IQR, 513.40 to 2,663.02], 499.82 mm3 [IQR, 167.77 to 1,229.80], P=0.002; 0.18 [IQR, 0.08 to 0.46], 0.40 pg/mL/mm3 [IQR, 0.16 to 1.29], P=0.016, respectively). Adenoma radioactivity was positively correlated with calcium, iPTH, and volume (r=0.180, P=0.020; r=0.208, P=0.006; r=0.288, P<0.001, respectively), but not with iPTH/volume. CONCLUSION: Parathyroid adenomas with positive MIBI scans had larger volumes and higher iPTH than adenomas with negative scans, but lower iPTH per unit volume.

Original Preoperative Localization Technique of Parathyroid Adenomas by 3-Dimensional Virtual Neck Exploration.

Objective. Preoperative imaging in primary hyperparathyroidism (PHPT) is essential for planning of parathyroidectomy-particularly for selection of a minimally invasive approach. The objective of this cohort study was to evaluate the diagnostic precision of 3D virtual neck exploration (3D-VNE), to evaluate its impact on choice of surgical approach, and to document the correlation with long-term outcomes. Methods. 235 consecutive patients with PHPT were studied (January 2014 to December 2018), with 6-month follow-up. 220 patients had a preoperative computed tomography (CT), 172 of these had a 3D-VNE based on the CT, and 226 patients had a Tc-99m sestamibi scan. Results. Sensitivity of exact, per gland, adenoma localization was 57.09% (95% CI: 50.85-63.10%) for nonspecialized radiologist interpretation of CT scan, 58.17% (95% CI: 51.99-64.10%) for Tc-99m sestamibi scan, and 90.21% (95% CI: 85.21-93.64%) for 3D-VNE, and thereby favoring 3D-VNE compared to CT scan alone (OR 34.5, 95% CI: 9.19-290.56%, P < 2.2 × 10-16) and to Tc-99m sestamibi scan (OR 16.25, 95% CI: 6.05-61.42%, P = 3.1 × 10-15). Specificity was 87.38% for CT scan, 86.36% for 3D-VNE, and 90% for Tc-99m sestamibi scan (P > .05). The cure rate was 100%. The long-term recurrence rate (RR) was 2.978%. The RR was 1.324% in the video-assisted parathyroidectomy group of 151 patients and 5.952% in the group of 84 patients with cervicotomy (P = .0459). Conclusion. CT-based 3D-VNE proved to be the most accurate localizing study in PHPT and aided in selecting patients for targeted minimally invasive parathyroidectomy, which was associated with the lower recurrence rate. 3D-VNE could be proposed as a first-line imaging study in patients with PHPT.

Factors related to a non-localising technetium 99m sestamibi scan result during parathyroid adenoma imaging in primary hyperparathyroidism.

OBJECTIVES: The aim of this study is to investigate factors that are associated with having a non-localising 99m Tc-sestamibi scan. DESIGN: A retrospective study was performed on patients that underwent parathyroid surgery performed within a single institution between 2001 and 2018. SETTING: Single tertiary centre for parathyroid surgery. PARTICIPANTS: 230 patients underwent surgery for primary hyperparathyroidism due to a solitary parathyroid adenoma and had preoperative 99m Tc-sestamibi imaging. MAIN OUTCOME MEASURES: Variables including age, gender, intra-operative location of parathyroid adenoma, adenoma weight and pre- and postoperative calcium and parathyroid hormone levels were investigated through univariate and multivariate analysis to identify any association with having a non-localising (negative) 99m Tc-sestamibi scan result. RESULTS: Multivariate analysis identified that right-sided adenomas (P = .038), superior adenomas (P = .042) and a lower preoperative PTH level (P = .034) were all individual factors associated with having a negative 99m Tc-sestamibi scan result. Although the weight of the adenoma was significant on univariate analysis (P = .029), this was not demonstrated on multivariate analysis (P = .422). CONCLUSION: Factors that were associated with having non-localising 99m Tc-sestamibi scan were right-sided adenomas, superior adenomas and lower preoperative PTH level. Further large prospective multicentre studies are needed to further evaluate these initial findings.

Application of radionuclide imaging in the diagnosis and management of Gaucher′s disease / 中华核医学与分子影像杂志

Gaucher′s disease (GD) is a lysosomal storage disease, and the etiology of GD is the decreased activity of glucocerebrosidase, which leads to the accumulation of glucocerebroside in the lysosomes of macrophages. Because GD is rare and lacks specific clinical manifestations, it is easy to be misdiagnosed, which delays the best time for treatment. Early diagnosis, clinical evaluation, and regular monitoring of the disease have important clinical significance for enzyme replacement therapy in patients with GD. Recent studies have found that radionuclide imaging is playing an increasingly important role in the diagnosis and treatment of GD. This article introduces the application of radionuclide imaging in the diagnosis and management of GD.

Experimental study of SPECT myocardial blood flow quantitative analysis in animals with coronary microvascular disease / 中华核医学与分子影像杂志

Objective:To compare the quantitative parameters of myocardial blood flow based on SPECT imaging and those determined by PET imaging in coronary microvascular disease (CMVD) animal models, in order to clarify the accuracy and feasibility of SPECT quantitative analysis in CMVD.Methods:Seven Saanen milk goats (either male or female; (20±5) kg), were selected for establishing CMVD animal models by microsphere embolization. Dynamic myocardial perfusion imaging (DMPI) with one-day method of resting + ATP stress 99Tc m-methoxyisobutylisonitrile (MIBI) SPECT was performed before and after the modeling, respectively. One-day method of resting + ATP stress 13N-ammonia PET DMPI was performed after the modeling. The quantitative parameters determined by SPECT and PET after the modeling, including stress myocardial blood flow (SMBF), resting myocardial blood flow (RMBF) and myocardial flow reserve (MFR), were compared by paired t test. Parameters based on SPECT after modeling were compared with those of baseline levels. Bland-Altman analysis was applied to access the agreement between SPECT and PET. Results:Four of the seven experimental goats were fully imaged. The RMBF(ml·g -1·min -1; 1.52±0.27 vs 1.29±0.20), SMBF(ml·g -1·min -1; 0.74±0.19 vs 0.99±0.26), and MFR (0.53±0.16 vs 0.76±0.10) of the left ventricle (global) obtained by SPECT and PET in CMVD models were not significantly different ( t values: 3.121, 1.195, 1.930, all P>0.05). Among left anterior descending branch (LAD), left circumflex (LCX) and right coronary artery (RCA), the RMBF, SMBF and MFR values quantified by SPECT and PET were neither statistically significant ( t values: 0.182-2.734, all P>0.05). Bland-Altman analysis showed the quantitative parameters measured by SPECT and PET DMPI in left ventricle, LAD, LCX, RCA had a good consistency. The difference between the two methods for determining RMBF was up to 0.63 ml·g -1·min -1, and that of SMBF was up to 0.66 ml·g -1·min -1. All points are within the 95% confidence limit; MFR differs at most by 0.56, and 14/16 points were within 95% confidence limit. The RMBF (ml·g -1·min -1) of left ventricle measured by SPECT after modeling was not significantly different from that before modeling (1.52±0.27 vs 1.57±0.36; t=0.166, P>0.05); the SMBF (ml·g -1·min -1) and MFR after modeling were significantly lower than those before modeling (0.74±0.19 vs 2.34±0.89, 0.53±0.16 vs 1.39±0.31, t values: 3.836, 6.309, both P<0.05). Similar results were found when comparing the parameters of LAD/LCX/RCA after modeling with those before modeling (RMBF t values: 0.191, 0.235, 0.195, all P>0.05; SMBF/MFR t values: 0.411-19.911, all P<0.05). Conclusion:The blood flow quantitative parameters measured by SPECT imaging have a good consistency with those based on PET imaging, and the myocardial blood flow quantitative analysis of SPECT can evaluate the blood flow perfusion of CMVD.

A feasibility study of 99Tc m-MIBI/ 123I-MIBG dual-isotope cardiac imaging using CZT SPECT / 中华核医学与分子影像杂志

Objective:To study the feasibility of cardiac 99Tc m-methoxyisobutylisonitrile (MIBI)/ 123I-metaiodobenzylguanidine (MIBG) dual-isotope imaging with cadmium-zinc-telluride (CZT) SPECT. Methods:Using a heart phantom, 99Tc m-MIBI single-isotope imaging and 99Tc m-MIBI/ 123I-MIBG dual-isotope imaging were acquired separately. Model A, B, C represented normal heart, 99Tc m/ 123I matched myocardium, 99Tc m/ 123I mismatched myocardium, respectively. Nineteen patients (9 males, 10 females; age (56±16) years) from September 2018 to June 2020 at Fuwai Hospital were enrolled to participate 99Tc m-MIBI myocardial perfusion imaging and myocardial perfusion/cardiac sympathetic imaging with 99Tc m-MIBI/ 123I-MIBG dual-isotope. Perfusion percent (PP%) and summed rest score (SRS) for all myocardial segments were obtained using quantitative perfusion SPECT (QPS) software by analyzing myocardial perfusion images. Difference and relationship between PP% and SRS were analyzed (Pearson and Spearman correlation analyses). No physical correction was applied for both acquisitions. Analysis of variance for repeated measurement data and Mann-Whitney U test were used. Results:There was no significant difference in myocardial perfusion images between 99Tc m single-isotope and 99Tc m/ 123I dual-isotope imaging with the heart phantom. 123I did not significantly impact on 99Tc m images. For patients, PP% did not differ between 99Tc m single-isotope ((69.2±14.5)%) and 99Tc m/ 123I dual-isotope imaging ((69.5±16.2)%; F=0.005, P=0.946) and correlated well ( r=0.845, P<0.01). SRS for 99Tc m single-isotope was 2(1, 13) and 2(2, 12) for 99Tc m/ 123I dual-isotope imaging ( z=-0.774, P=0.439) and the correlation between the two acquisitions was excellent ( rs=0.975, P<0.01). Conclusions:Even without physical correction, cardiac images interpretation won′t be significantly influenced by the interference of 123I with relatively higher energy on 99Tc m images. Cardiac 99Tc m-MIBI/ 123I-MIBG dual-isotope imaging is feasible.