Metaiodobenzylguanidine Scintigraphy Research Articles

Electroconvulsive therapy for dementia with Lewy bodies: A systematic review and Japanese multicenter survey.

Management of psychiatric symptoms in dementia with Lewy bodies (DLB) is challenging due to hypersensitivity to psychotropic medications. Electroconvulsive therapy (ECT) is a potential therapeutic option for DLB, but its efficacy and safety remain uncertain. We systematically reviewed articles on ECT for DLB, including those published in Japanese-language journals, and surveyed institutions certified by the Japanese Psychogeriatric Society. Of 41 peer-reviewed articles, 32 were from Japan. The proportion of prodromal DLB cases was significantly higher in Japan (34.8 %) than in other countries (9.5 %) (p = 0.044). Cardiac [123I]-metaiodobenzylguanidine scintigraphy and/or striatal dopamine transporter imaging were significantly more frequently in Japan (71.8 %) than in other countries (5.5 %) (p < 0.001). ECT has shown effectiveness in treating depression, catatonia, agitation and psychosis. It was generally considered safe, with transient delirium being the most common side effect, occurring in 16.1 % of Japanese cases. However, current evidence is limited to case studies and lacks randomized controlled trials. The survey confirmed that ECT is widely performed for DLB in Japan, although the number of cases treated varied greatly across institutions. These findings underscore the need for standardized ECT guidelines for DLB. Multicenter studies with standardized assessments and longitudinal follow-up are essential to further research on ECT for DLB, including psychiatric-onset prodromal DLB.

The Pediatric Neuroblastoma: Application of MIBG Scintigraphy in Diagnosis, Staging, and Follow-up – Analysis of Three Cases

Introduction: Neuroblastoma is the most common extracranial solid tumor in children, accounting for 8-10% of all pediatric cancers. Accurate diagnosis and management rely on imaging modalities and biological markers such as elevated urinary catecholamines. Among the various imaging techniques, Metaiodobenzylguanidine (MIBG) scintigraphy, often combined with SPECT/CT, provides high specificity for neuroblastoma cells. It is crucial for determining tumor extent, identifying metastatic disease, and monitoring therapeutic response. Materials and Methods: This study presents three clinical cases illustrating the role of MIBG scintigraphy in the diagnosis, staging, and follow-up of pediatric neuroblastoma. The three patients underwent Iodine-131 labeled MIBG scintigraphy, with planar imaging, and in two cases, additional SPECT/CT imaging. Results : Case 1: A 3-year-old child with a right adrenal mass and diffuse bone marrow metastases, classified as stage IV neuroblastoma. Case 2: An 11-year-old girl with recurrent retroperitoneal neuroblastoma identified during follow-up MIBG scintigraphy. Case 3: An 11-year-old girl with no evidence of disease progression, confirmed by MIBG scintigraphy, indicating complete remission. Conclusion: MIBG scintigraphy is an invaluable tool in the management of neuroblastoma, offering precise tumor localization, accurate staging, and effective monitoring of treatment response. Its integration into clinical practice helps guide therapeutic decisions and improves patient outcomes.

Feasibility of a single-day protocol for SPECT and PET assessment of dopamine transporter availability, cardiac innervation and metabolic patterns in patients with movement disorders

Abstract Purpose Due to new advances in molecular and imaging biomarkers, a biological classification of Parkinson’s disease (PD) called SyNeurGe (Hoglinger et al. Lancet Neurol 2024;23:191-204) has been proposed for research use recently. [123I]ioflupane dopamine transporter single-photon-emission-computed tomography (DaT-SPECT) and cardiac [123I]meta-iodobenzylguanidine (MIBG) scintigraphy are included in this biological classification scheme together with 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) as central imaging biomarkers for the assessment of dopaminergic function, cardiac sympathetic denervation, and metabolic patterns in brain. In order to facilitate this prospectively high imaging demand and optimize diagnostic workup in PD we propose a single-day protocol. Methods First, we excluded relevant binding of MIBG in the brain as well as DaT in the heart by acquisition of brain scans in patients that received MIBG as well as by acquisition of chest scans in patients that received DaT. Then, we performed a single-day protocol including DaT-SPECT and cardiac MIBG scintigraphy in ten patients with clinically suspected α-synucleinopathies (9 male, 1 female; 68.2 ± 7.3 years). Both radiotracers were injected simultaneously and cardiac imaging was performed at 3.5 h after injection followed by brain imaging at 4 h after injection using standard protocols for MIBG-scintigraphy and DaT-SPECT. Additionally, five patients of the dual tracer protocol group received brain FDG-PET after DaT and MIBG imaging. Results Single tracer imaging confirmed no relevant uptake of [123I]ioflupane in the heart or [123I]MIBG in the brain. Six out of the ten dual tracer protocol patients (PD or multiple system atrophy with Parkinsonian phenotype (MSA-P)) showed a significantly reduced DaT-SPECT binding (z-score &lt; -2) in at least one hemisphere (mean putaminal z-score -4.01 ± 1.39) while seven patients had a pathological heart-to-mediastinum ratio in the MIBG scan (mean H/M-ratio: 1.12 ± 0.08). Both DaT and MIBG scans could visually be interpreted without any signs of image artifacts or decrease in imaging quality and also quantitatively did not reveal significant differences to the single tracer scans. FDG-PET brain scans of the triple tracer protocol patients also showed no relevant interference in regard to image quality as well was generation of surface projections and z-scores. Conclusion A single day protocol for DaT-SPECT, MIBG, and FDG-PET facilitates biomarker assessments needed for efficient biological characterization of Parkinsonian syndromes according to the SyNeurGe criteria.

A Case of Paraganglioma of the Spermatic Cord

A49-year-old man noticed discomfort in the right scrotum and consulted a nearby medical institution. Magnetic resonance imaging revealed a 10 mm tumor in the right spermatic cord, showing low signal intensity on T1-weighted images and high signal intensity on T2-weighted and diffusion-weighted images. Since malignancy could not be ruled out, he was referred to our hospital. Physical examination revealed an elastic, mobile tumor in the right spermatic cord. Ultrasonography showed a solid tumor measuring 10 mm near the right testicle. Although differential diagnoses included lipoma and neurilemmoma, the possibility of malignancy prompted tumor resection. The tumor was a nodular lesion with a clear brown border. Histopathological examination confirmed the diagnosis of paraganglioma. Postoperative metaiodobenzylguanidine scintigraphy, computed tomographic imaging, and hormone testing did not reveal any significant findings, confirming the diagnosis of paraganglioma originating from the spermatic cord.

Three cases of gastrointestinal stromal tumors with metaiodobenzylguanidine (MIBG) accumulation.

Meta-iodobenzylguanidine (MIBG) is an analog of norepinephrine and guanethidine, and MIBG scintigraphy is useful to diagnose tumors of the sympathetic nervous system, such as pheochromocytoma, paraganglioma, and neuroblastoma. To date, there have been few reports of MIBG accumulation in gastrointestinal stromal tumors (GISTs), so the mechanism and frequency of MIBG accumulation in GISTs are unknown. Herein, we report and discuss three cases of GIST in which scintigraphy that was performed to exclude pheochromocytoma showed MIBG accumulation.

Application of modified Curie and SIOPEN skeleton scoring systems in 18F-AlF-NOTA-octreotide PET/CT for neuroblastoma.

The study aimed to explore the role of fluorine-18-aluminum fluoride-1,4,7-triazacyclononane-1,4,7-triacetic acid-octreotide (18F-OC) positron emission tomography/computed tomography (PET/CT) in neuroblastoma (NB) and compared it with Iodine-123 labeled metaiodobenzylguanidine (123I-MIBG) scintigraphy with single photon emission computed tomography/computed tomography (SPECT/CT), as well as to investigate the feasibility of the modified Curie scoring system and International Society of Pediatric Oncology Europe Neuroblastoma (SIOPEN) skeleton scoring system applied in 18F-OC PET/CT. Patients with pathologically confirmed NB underwent 123I-MIBG scintigraphy with SPECT/CT and 18F-OC PET/CT according the standard imaging protocols. The interval between the two imaging techniques ranged from 0 to 22days (median interval: 9days). The number of lesions in modified Curie scoring system and SIOPEN skeleton scoring system applied on 123I-MIBG SPECT/CT and 18F-OC PET/CT was compared. A total of 50 NB patients (male: female = 25:25) with a median age of 62-month-old were enrolled. 123I-MIBG and 18F-OC imaging were positive in 22 patients and negative in 27 patients. 1 patient had positive 18F-OC but negative 123I-MIBG results (p = 1.000). In lesion-based analysis, 18F-OC PET/CT revealed more positive lesions than 123I-MIBG scintigraphy with SPECT/CT (57 vs. 44, p < 0.001), regardless of bone/bone marrow lesions (43 vs. 37, p = 0.031) or soft tissue lesions (14 vs. 7, p = 0.016). The Curie scores of the two imaging techniques showed a significant difference (p = 0.047), whereas no statistic difference for SIOPEN scores (p = 0.688). The Curie and SIOPEN scores were significantly higher in patients with the presence of MYCN amplification or positive bone marrow puncture result (p < 0.05). 18F-OC could be used in the evaluation of NB, and the modified Curie scoring system could be used to semi-quantify the disease extent of NB in 18F-OC PET/CT.

The relationship between lung MIBG uptake and clinical response to renal denervation

Abstract Background Renal denervation (RDN) reduces the sympathetic overdrive and can optimize blood pressure control in patients with difficult-to-treat hypertension (DTH). However, a substantial proportion of patients undergoing RDN do not show a clinical response to the procedure, making it critical to identify novel and more accurate predictors. The metaiodobenzylguanidine (MIBG) scintigraphy allows non-invasive assessment of sympathetic nerve activity. Yet, studies evaluating the heart and kidney MIBG uptake as predictors of clinical response to RDN provided conflicting results, and a comprehensive evaluation of the MIBG uptake in different organs of DTH patients undergoing RDN is lacking. Purpose To explore if a more comprehensive evaluation of MBG uptake in the kidneys, heart and lungs can predict the clinical response to RDN. Methods Eighteen patients with DTH underwent evaluation of their clinical and pharmacological history, office and ambulatory BP values and levels of cardiovascular risk factors. A rest echocardiography, carotid vascular ultrasound and MIBG scintigraphy were also performed before RDN. The patient’s pharmacological history and office and ambulatory BP values were re-evaluated after 3 months from RDN. We considered responders (R) those subjects with a significant reduction of the office BP values on stable BP-lowering treatment or a reduced burden of BP-lowering medications while maintaining optimal control of the office BP. Results Ten patients could be classified as R (1 woman, mean age 49±10 years), while 7 were non-responders (NR, 2 women, mean age 53±8 years). The reduction in office systolic and diastolic BP (baseline vs 3 months) was significantly larger in R vs NR (p=0.01 for both). The burden of BP-lowering medications after the procedure was reduced by 39% in R, compared to 2% in NR (p&amp;lt;0.01). Responders had a higher baseline HR and prevalence of carotid atherosclerosis than NR (p&amp;lt;0.05 for both). In early MIBG acquisitions, the lung/mediastinum ratio on both sides showed higher MIBG uptake in R vs NR (p&amp;lt;0.05). There was a higher MIBG uptake in the right vs. left lung in the whole population and in R vs NR. In late acquisitions, only the left side showed a significant difference between R and NR (p&amp;lt;0.05). The associations between the lung/mediastinum ratio MIBG uptake and response to RDN remained significant after adjusting for the baseline clinical predictors of the RDN response. All other MIBG scintigraphy parameters were similar between groups. Conclusions Our results suggest that RDN might be less effective in patients with an advanced burden of hypertension-mediated target organ damage and confirm a higher HR as a reliable predictor of the clinical response to the procedure. We also document a novel association between the lung/mediastinum ratio MIBG uptake and response to RDN that, if confirmed in future studies, might provide a novel marker to improve the selection of patients undergoing RDN.

Plasma biomarkers of neurodegeneration in patients and high risk subjects with Lewy body disease

Comorbid Alzheimer’s disease (AD) neuropathology is common in Lewy body disease (LBD); however, AD comorbidity in the prodromal phase of LBD remains unclear. This study investigated AD comorbidity in the prodromal and symptomatic phases of LBD by analyzing plasma biomarkers in patients with Parkinson’s disease (PD) and dementia with Lewy bodies (DLB) and individuals at risk of LBD (NaT-PROBE cohort). Patients with PD (PD group, n = 84) and DLB (DLB group, n = 16) and individuals with LBD with ≥ 2 (high-risk group, n = 82) and without (low-risk group, n = 37) prodromal symptoms were enrolled. Plasma amyloid-beta (Aβ) composite was measured using immunoprecipitation-mass spectrometry assays. Plasma phosphorylated tau 181 (p-tau181), neurofilament light chain (NfL), and alpha-synuclein (aSyn) were measured using a single-molecule array. Plasma p-tau181 levels were higher in the PD and DLB groups than in the low-risk group. Aβ composite level was higher in the DLB group than in the high-risk group. AD-related biomarker levels were not elevated in the high-risk group. NfL levels were higher in the high-risk, PD, and DLB groups than in the low-risk group. In the PD group, Aβ composite was associated with cognitive function, p-tau181 with motor function and non-motor symptoms, and NfL with cognitive and motor functions and non-motor symptoms. In the high-risk group, NfL was associated with metaiodobenzylguanidine scintigraphy abnormalities. The PD and DLB groups exhibited comorbid AD neuropathology, though not in the prodromal phase. Elevated plasma NfL levels, even without elevated AD-related plasma biomarker levels, may indicate aSyn-induced neurodegeneration in the LBD prodromal phase.

Clinical presentations and diagnostic application of proposed biomarkers in psychiatric-onset prodromal dementia with Lewy bodies.

Research criteria for the diagnosis of prodromal dementia with Lewy bodies (DLB) include three clinical subtypes: mild cognitive impairment with Lewy bodies (MCI-LB), delirium-onset prodromal DLB, and psychiatric-onset prodromal DLB. Late-onset psychiatric manifestations are at a higher risk of developing dementia, but its relation to prodromal DLB remains unclear. In addition to the risk of severe antipsychotic hypersensitivity reactions, accurate discrimination from non-DLB cases is important due to the potential differences in management and prognosis. This article aims to review a rapidly evolving psychiatric topic and outline clinical pictures of psychiatric-onset prodromal DLB, including the proposed biomarker findings of MCI-LB: polysomnography-confirmed rapid eye movement sleep behaviour disorder, cardiac [123I]metaiodobenzylguanidine scintigraphy, and striatal dopamine transporter imaging. We first reviewed clinical pictures of patients with autopsy-confirmed DLB. Regarding clinical reports, we focused on the patients who predominantly presented with psychiatric manifestations and subsequently developed DLB. Thereafter, we reviewed clinical studies regarding the diagnostic applications of the proposed biomarkers to patients with late-onset psychiatric disorders. Clinical presentations were mainly late-onset depression and psychosis; however, other clinical manifestations were also reported. Psychotropic medications before a DLB diagnosis may cause extrapyramidal signs, and potentially influences the proposed biomarker findings. These risks complicate clinical manifestation interpretation during the management of psychiatric symptoms. Longitudinal follow-up studies with standardised evaluations until conversion to DLB are needed to investigate the temporal trajectories of core features and proposed biomarker findings. In patients with late-onset psychiatric disorders, identification of patients with psychiatric-onset prodromal DLB provides the opportunity to better understanding the distinct prognostic subgroup that is at great risk of incident dementia. Advances in the establishment of direct biomarkers for the detection of pathological α-synuclein may encourage reorganising the phenotypic variability of prodromal DLB.

Evaluation of pharmacokinetics, safety, and efficacy of [211At] meta-astatobenzylguanidine ([211At] MABG) in patients with pheochromocytoma or paraganglioma (PPGL): A study protocol.

Pheochromocytoma, or paraganglioma (PPGL), is a tumor that arises from catecholamine-producing chromaffin cells of the adrenal medulla or paraganglion. Systemic therapy, such as the combination of cyclophosphamide, vincristine, and dacarbazine or therapeutic radiopharmaceuticals such as [131I] meta-iodobenzylguanidine (MIBG), may be administered in cases of locally advanced tumors or distant metastases. However, the current therapies are limited in terms of efficacy and implementation. [211At] meta-astatobenzylguanidine (MABG) is an alpha-emitting radionuclide-labeled ligand that has demonstrated remarkable tumor-reducing effects in preclinical studies, and is expected to have a high therapeutic effect on pheochromocytoma cells. We are currently conducting an investigator-initiated first-in-human clinical trial to evaluate the pharmacokinetics, safety, and efficacy of [211At] MABG. Patients with locally unresectable or metastatic PPGL refractory to standard therapy and scintigraphically positive [123I] MIBG aggregation are being recruited, and a 3 + 3 dose escalation design was adopted. The initial dose of [211At] MABG is 0.65 MBq/kg, with a dose escalation in a 1:2:4 ratio in each cohort. Dose-limiting toxicity is observed for 6 weeks after a single bolus dose of [211At] MABG, and the patients are observed for 3 months to explore safety and efficacy profiles. The primary endpoint is dose-limiting toxicity to determine both maximum tolerated and recommended doses. The secondary endpoints include radiopharmacokinetics, urinary radioactive excretion rate, urinary catecholamine response rate, objective response rate, progression free survival, [123I] MIBG scintigraphy on reducing tumor accumulation, and quality of life. jRCT2021220012 registered on 17 June 2022.

Decreased heart rate variability in sympathetic dominant states in Parkinson's disease and isolated REM sleep behavior disorder

Decreased heart rate variability in sympathetic dominant states in Parkinson's disease and isolated REM sleep behavior disorder

Impairment of Cognitive Function Increases Mortality Risk in Relation to Cardiac Sympathetic Denervation and Renal Dysfunction in Patients With Systolic Heart Failure

In contrast to the well-known prognostic values of the cardiorenal linkage, it remains unclear whether impaired cognitive function affects cardiac prognosis in relation to cardiac sympathetic innervation and renal function in patients with heart failure (HF). A total of 433 consecutive HF patients with left ventricular ejection fraction (LVEF) <50% underwent the Mini-Mental State Examination (MMSE) and a neuropsychological test for screening of cognition impairment or subclinical dementia. Following metaiodobenzylguanidine (MIBG) scintigraphy, patient outcomes with a primary endpoint of lethal cardiac events (CEs) were evaluated for a mean period of 14.8 months. CEs were documented in 84 HF patients during follow-up. MMSE score, estimated glomerular filtration rate (eGFR) and standardized heart-to-mediastinum ratio of MIBG activity (sHMR) were significantly reduced in patients with CEs compared with patients without CEs. Furthermore, overall multivariate analysis revealed that these parameters were significant independent determinants of CEs. The cutoff values of MMSE score (<26), sHMR (<1.80) and eGFR (<47.0 mL/min/1.73 m2) determined by receiver operating characteristic (ROC) analysis successfully differentiated HF patients at more increased risk for CEs from other HF patients. Impairment of cognitive function is not only independently related to but also synergistically increases cardiac mortality risk in association with cardiac sympathetic function and renal function in patients with HF.

Comparison between whole-body magnetic resonance imaging and whole-body metaiodobenzylguanidine scintigraphy in the evaluation of primary tumor and metastases in neuroblastoma.

Whole-body metaiodobenzylguanidine (131 I-MIBG) scintigraphy is the gold standard method to detect neuroblastoma; however, it depends on radioactive material and is expensive. In contrast, whole-body magnetic resonance imaging (WB-MRI) is affordable in developing countries and has been shown to be effective in the evaluation of solid tumors. This study aimed to compare the sensitivity and specificity of WB-MRI with MIBG in the detection of primary tumors and neuroblastoma metastases. This retrospective study enrolled patients with neuroblastoma between 2013 and 2020. All patients underwent WB-MRI and MIBG at intervals of up to 15days. The results were marked in a table that discriminated anatomical regions for each patient. Two experts evaluated, independently and in anonymity, the WB-MRI images, and two others evaluated MIBG. The results were compared in terms of sensitivity and specificity, for each patient, considering MIBG as the gold standard. This study was approved by the UNIFESP Ethics Committee. Thirty patients with neuroblastoma were enrolled in this study. The age ranged from 1 to 15years, with a mean of 5.7years. The interval between exams (WB-MRI and MIBG) ranged from 1 to 13days, with an average of 6.67days. Compared to MIBG, WB-MRI presented a sensitivity and specificity greater than or equal to 90% for the detection of primary neuroblastoma in bones and lymph nodes. When we consider the patient without individualizing the anatomical regions, WB-MRI presented sensitivity of 90% and specificity of 73.33%. In conclusion, WB-MRI is a sensitive and specific method to detect neuroblastoma in bone and lymph nodes and highly sensible to primary tumor diagnosis, suggesting that this test is a viable alternative in places where MIBG is difficult to access. Studies with a larger number of cases are necessary for definitive conclusions.

Diagnostic problems in pediatrics on the example of a clinical case of neuroblastoma

Neuroblastoma (NB) is a malignant extracranial solid tumor of childhood. The peak incidence occurs in the first year of life. In 50% of cases, the disease already has signs of metastasis at the time of diagnosis. The clinical picture in neuroblastoma is varied; the symptoms are not specific and depend on the localization. The diagnosis is confirmed by histological examination of the biopsy of the primary tumor and metastasis. A specific method for the topical diagnosis of neuroblastoma is 123I-labeled metaiodobenzylguanidine scintigraphy, which makes it possible to detect the primary tumor, the presence of regional and distant metastases. Combinations of high-dose chemotherapy and transplantation of autologous stem cells and differentiating agents, as well as immunotherapy with anti-GD2 monoclonal antibodies, can increase the life expectancy of patients.

Impact of diabetes and glycated hemoglobin level on the clinical manifestations of Parkinson's disease

Impact of diabetes and glycated hemoglobin level on the clinical manifestations of Parkinson's disease

Exploring the prevalence of undetected bradyarrhythmia in dementia with Lewy bodies

PurposeTo explore the prevalence of undetected bradyarrhythmia in a cohort of people with dementia with Lewy bodies.MethodsThirty participants diagnosed with dementia with Lewy bodies were enrolled from three memory clinics in southern Sweden between May 2021 and November 2022. None had a history of high-grade atrioventricular block or sick sinus syndrome. Each participant underwent orthostatic testing, cardiac [123I]metaiodobenzylguanidine scintigraphy and 24-h ambulatory electrocardiographic monitoring. Concluding bradyarrhythmia diagnosis was obtained until the end of December 2022.ResultsThirteen participants (46.4%) had bradycardia at rest during orthostatic testing and four had an average heart rate < 60 beats per minute during ambulatory electrocardiographic monitoring. Three participants (10.7%) received a diagnosis of sick sinus syndrome, of whom two received pacemaker implants to manage associated symptoms. None received a diagnosis of second- or third-degree atrioventricular block.ConclusionThis report showed a high prevalence of sick sinus syndrome in a clinical cohort of people with dementia with Lewy bodies. Further research on the causes and consequences of sick sinus syndrome in dementia with Lewy bodies is thus warranted.

The role of MIBG scan in the diagnosis of pheochromocytoma.

e15064 Background: Pheochromocytoma is an uncommon adrenal medulla tumor. Metaiodobenzylguanidine (MIBG) scintigraphy is the current gold standard functional imaging method for evaluating pheochromocytoma, due to its excellent 100% specificity, 80% sensitivity, and general availability. In addition to establishing an extension evaluation and monitoring medication efficacy, MIBG scintigraphy is essential to confirm the diagnosis of suspected pheochromocytoma, especially when there is a tumor-like adrenal mass whose etiology is to be determined and biopsy is contraindicated given the risk of catecholamine discharge with hypertensive flare and the risk of bleeding. Our aims are to determine the efficacy of scintigraphy in the diagnosis of pheochromocytoma by examining the epidemiological characteristic and uptake patterns of the disease. Methods: In a retrospective analysis from January 2010 to December 2020, we examined pheochromocytoma patients medical records who had been referred for MIBG scintigraphy to the regional western Algerian Nuclear Medicine department at the University Hospital Center of Tlemcen. Prior to a progressive intravenous injection of 40–80 MBq of l-MIBG, patients underwent preparation (discontinuation of interfering drugs with I-MIBG especially antihypertensive treatment, thyroid blocking, and hydration). Imaging acquisition was carried out 48 and 72 hours later. Results: Fifty patients with probable pheochromocytoma (sex ratio = 0,78; mean age = 43 [17-74] years) completed I-MIBG scintigraphy prior to adrenalectomy. The MIBG scan has a high specificity and positive predictive value (100%). It confirms the presence of pheochromocytoma in 21 cases (42%), even if the metanephrine is normal in a patient with a non-secreting pheochromocytoma. In 18 cases, the main pattern is a single, homogenous, and intense intra-abdominal uptake. For the three remaining patients, a voluminous and heterogeneous uptake with a photopenic center that was associated to a necrotic adrenal mass larger than 10 cm in size, seen on abdominal Computerized Tomography (CT). In this retrospective analysis, no cases of metastatic or multiple diseases were documented. The sensitivity and negative predictive value are 84% and 86%, respectively. In 29 patients (58%), the scan reveals no abnormalities in uptake. This is attributed, in part, to 30% false positive biology (sampling conditions of urinary and/or plasmatic metanephrines and/or normetanephrines), 20% false positive CT imaging (differential diagnosis of adrenal mass: benign or malignant adrenal nodule), and 8% false negative MIBG scintigraphy (subcentimetric, cystic and necrotic lesion). Conclusions: Due to its exceptional specificity, robust sensitivity, and whole-body staging, MIBG scintigraphy—along with biology and morphology imaging—is a crucial noninvasive diagnostic method for the management of pheochromocytoma prior to adrenalectomy.

Clinico-imaging features of subjects at risk of Lewy body disease in NaT-PROBE baseline analysis

Individuals with prodromal symptoms of Lewy body disease (LBD), such as rapid eye movement sleep behavior disorder (RBD), often showed imaging defects similar to patients with Parkinson’s disease and dementia with Lewy bodies. We examined dopamine transporter (DaT) single-photon-emission computed tomography (SPECT) and metaiodobenzylguanidine (MIBG) scintigraphy in 69 high-risk subjects with ≥2 prodromal symptoms (dysautonomia, hyposmia, and probable RBD) and 32 low-risk subjects without prodromal symptoms, whom were identified through a questionnaire survey of health checkup examinees. The high-risk subjects had significantly worse scores on Stroop test, line orientation test, and the Odor Stick Identification Test for Japanese than the low-risk subjects. The prevalence of abnormalities on DaT-SPECT was higher in the high-risk group than in the low-risk group (24.6% vs. 6.3%, p = 0.030). A decreased uptake on DaT-SPECT was associated with motor impairment, and MIBG scintigraphy defects were associated with hyposmia. The simultaneous evaluation of DaT-SPECT and MIBG scintigraphy may capture a wide range of individuals with prodromal LBD.

Research diagnostic criteria for mild cognitive impairment with Lewy bodies: A systematic review and meta-analysis.

Operationalized research criteria for mild cognitive impairment with Lewy bodies (MCI-LB) were published in 2020. The aim of this systematic review and meta-analysis was to review the evidence for the diagnostic clinical features and biomarkers in MCI-LB set out in the criteria. MEDLINE, PubMed, and Embase were searched on 9/28/22 for relevant articles. Articles were included if they presented original data reporting the rates of diagnostic features in MCI-LB. Fifty-seven articles were included. The meta-analysis supported the inclusion of the current clinical features in the diagnostic criteria. Evidence for striatal dopaminergic imaging and meta-iodobenzylguanidine cardiac scintigraphy, though limited, supports their inclusion. Quantitative electroencephalogram (EEG) and fluorodeoxyglucose positron emission tomography (PET) show promise as diagnostic biomarkers. The available evidence largely supports the current diagnostic criteria for MCI-LB. Further evidence will help refine the diagnostic criteria and understand how best to apply them in clinical practice and research. A meta-analysis of the diagnostic features of MCI-LB was carried out. The four core clinical features were more common in MCI-LB than MCI-AD/stable MCI. Neuropsychiatric and autonomic features were also more common in MCI-LB. More evidence is needed for the proposed biomarkers. FDG-PET and quantitative EEG show promise as diagnostic biomarkers in MCI-LB.

Pitfalls in the diagnosis and treatment of a hypertensive patient with unilateral primary aldosteronism and contralateral pheochromocytoma: a case report

BackgroundPrimary aldosteronism (PA) is a common cause of secondary hypertension, whereas pheochromocytoma is a rare cause of it. Thus, concomitant PA and pheochromocytoma is a very rare condition.Case presentationA 52-year-old woman was admitted to our hospital with suspected PA based on the presence of hypertension, spontaneous hypokalemia, and a high aldosterone-to-renin ratio. She had no catecholamine excess symptoms other than hypertension. Abdominal computed tomography (CT) showed a right lipid-rich adrenal mass and a left lipid-poor adrenal mass. PA was diagnosed by the captopril challenge test. The 24-h urinary fractionated metanephrines were slightly elevated. Adrenal vein sampling (AVS) confirmed that the right adrenal gland was responsible for aldosterone hypersecretion. Medical therapy with eplerenone was started because the patient refused surgery. Five years later, she requested surgery for PA. The second AVS confirmed right unilateral hyperaldosteronism, as expected. Repeated abdominal CT showed the enlargement of the left adrenal mass. The 24-h urinary fractionated metanephrines had risen to the diagnostic level. 123I- metaiodobenzylguanidine (MIBG) scintigraphy showed a marked tracer uptake in the left adrenal mass with no metastatic lesion. After preoperative management with α-blockade, laparoscopic left partial adrenalectomy was performed. Immunohistochemical examination of the tumor showed chromogranin A positivity leading to the diagnosis of left pheochromocytoma.ConclusionsWe report an extremely rare case of concomitant unilateral PA and contralateral pheochromocytoma. When diagnosing unilateral PA by AVS, especially in cases with a lipid-poor adrenal mass, clinicians should rule out the possibility of the presence of pheochromocytoma before proceeding to undergo unilateral adrenalectomy. Although there is no standard treatment for this rare condition, it is essential to select personalized treatment from the perspective of conserving the adrenal gland.