Normocalcemic primary hyperparathyroidism: 99mTc SestaMibi SPECT/CT results compare with hypercalcemic hyperparathyroidism.

CONTEXT: Normocalcemic primary hyperparathyroidism (nPHPT) is defined by an inappropriately increased serum PTH with normal serum calcium. Information about the diagnostic yield of parathyroid SPECT/CT scan and ultrasonography in nHPPT is limited and not conclusive. PURPOSE: To evaluate the positivity rate of 99m Tc-Sestamibi SPECT/CT scan in nPHTP compared with classical hypercalcemic PHPT (cPHPT). MATERIALS AND METHODS: We retrospectively studied 125 patients with 99m Tc-Sestamibi SPECT/CT scans. Subjects were divided into 2 groups: cPHPT (n = 93) and nPHPT (n = 32). RESULTS: The detection rate of 99m Tc-Sestamibi SPECT/CT in cPHPT was 86,02% (80/93) and 59.37%, in nPHPT (19/32), p = .003. No significant differences were seen between the SPECT/CT scan and ultrasonography (p = .28) and the agreement was higher in cPHPT than in nPHPT, p = .03. Sensitivity of 99m Tc-Sestamibi-SPECT/CT was 98% on a per-patient basis (PPV 96%) and 91% on a per-lesion basis (PPV 88%). Glandular size was smaller in nPHPT (mean value 6.8 mm) and it was related only with PTH value. CONCLUSION: Localization rate of parathyroid hyperfunctioning tissue with 99m Tc-Sestamibi SPECT/CT is lower in nPHPT and it is related to a smaller glandular size. However, our study suggests that the positivity rate and sensitivity are nonnegligible by adding SPECT/CT. The reduction in the detection rate in nPHPT could benefit techniques with higher resolution such as 18 F-Choline PET/CT when the clinical context justifies it.

Head-to-head comparison among 18F-choline PET/CT, 4D contrast-enhanced CT, and 18F-choline PET/4D contrast-enhanced CT in the detection of hyperfunctioning parathyroid glands: a systematic review and meta-analysis.

INTRODUCTION: In primary hyperparathyroidism (PHPT), the localization of hyperfunctioning parathyroid gland (HPTG) allows tailored surgery. Although Four-Dimensional Contrast-enhanced Computed Tomography (4DCeCT) and 18F-choline Positron Emission Tomography/Computed Tomography (PET/CT) are reported to be promising second-line imaging procedures, no meta-analysis of their comparison exists. DESIGN: we conducted a systematic review and meta-analysis to find original papers reporting the head-to-head comparison of 4DCeCT, 18F-choline PET/CT and integrated 18F-choline-PET/4DCeCT. METHODS: this systematic review was conducted according to PRISMA. PubMed, CENTRAL, Scopus, and Web of Science were searched until January 2021. Studies comparing the ability of 4DCeCT, 18F-choline PET/CT and 18F-choline PET/4DCeCT to identify HPTG in patients with PHPT were selected. A per patient-based analysis of the three procedures was conducted in all patients (detection rate, DR) and in those with histologically confirmed HPTG (sensitivity). RESULTS: Of the 78 records identified, five articles (153 PHPT patients) published between January the 1st, 2018 and January the 31st, 2021 were included. The pooled DR of 18F-choline PET/CT, 4DCeCT and 18F-choline PET/4DCeCT was 0.86, 0.69, and 0.86, respectively, while their pooled sensitivity was 0.89, 0.77 and 0.93, respectively. The analysis of pooled discrepancy showed that the sensitivity of 18F-choline PET/CT and 18F-choline PET/4DCeCT was higher than that of 4DCeCT by 0.11 and 0.13, respectively, the sensitivity of 18F-choline PET/4DCeCT being 0.06 higher than that of 18F-Choline PET/CT. CONCLUSIONS: This meta-analysis suggests that the sensitivity of 18F-choline PET/CT and 18F-choline PET/4DCeCT is higher than that of 4DCeCT, while only a slight difference was observed between 18F-choline PET/CT and 18F-choline PET/4DCeCT.

Factores asociados a placa blanda en pacientes con score de calcio igual a cero / Factors Associated with Non-calcified Plaques in Patients with Coronary Artery Calcium Score of Zero

RESUMEN Introducción: El score de calcio es una prueba utilizada en la estratificación de riesgo de pacientes asintomáticos. Aunque la enfermedad coronaria puede producirse en ausencia de calcificaciones, no se han descripto afecciones asociadas a la presencia de placa blanda en este contexto, más allá de la presencia de síntomas. Objetivos: Determinar asociaciones entre la presencia de placa blanda y variables independientes en pacientes con un score de calcio de cero. Material y métodos: Se incluyeron pacientes consecutivos con un score de calcio de 0 unidades Agatston que se hubieran realizado, además, una angiotomografía coronaria. Se determinaron asociaciones a partir de análisis univariado. Se calculó la sensibilidad, especificidad, VPN, VPP, +LR y -LR. Resultados: Se incluyeron en el estudio 93 pacientes. El 10% (n = 9) presentaron placa blanda. La ergometría positiva se asoció a placas de cualquier gravedad (OR 6,5; IC del 95%: 1,3-33, p = 0,02). Esta asociación persistió para placas no graves cuando se combinó la ergometría positiva con perfusión miocárdica SPECT o ecocardiograma estrés negativos para isquemia (OR 12,4 IC 95% 1,5-101, p = 0,02). La sensibilidad y la especificidad del infradesnivel del ST para placa blanda de cualquier nivel de gravedad fue del 44,4% y del 86%, respectivamente. El VPN fue del 94% y el VPP del 25%, LR+ fue de 3,11 y LR- fue de 0,65. Conclusiones: El infradesnivel del ST se asociaría a la presencia de placa blanda en pacientes sin calcificaciones coronarias, incluso en contexto de perfusión miocárdica o motilidad parietal en esfuerzo normales (enfermedad no obstructiva).

ABSTRACT Background: The coronary artery calcium score is used for risk stratification in asymptomatic patients. Although coronary artery disease can occur in the absence of coronary artery calcifications, no conditions associated with the presence of soft non-calcified plaques have been described in this scenario, beyond the presence of symptoms. Objectives: The aim of this study was to determine the associations between non-calcified plaques and independent variables in patients with coronary artery calcium score of zero. Methods: Consecutive patients with coronary artery score of zero Agatston units who also underwent computed tomography coronary angiography were included in the study. Univariate logistic regression analysis was used to find associations. (15) Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LH+) and negative likelihood ratio (LH-) were calculated. Results: Among a total of 93 patients, 10% (n=9) presented non-calcified plaque. A positive exercise stress test was associated with plaques of any degree of severity (OR 6.5; 95% CI, 1.3-33, p=0.02). This association persisted for non-severe plaques when the positive exercise stress test was combined with a negative myocardial perfusion SPECT or stress echocardiography for ischemia (OR, 12.4; 95% CI 1.5-101, p=0.02). Sensitivity and specificity of ST-segment depression for non-calcified plaque of any degree of severity was 44.4% and 86%, respectively, with NPV of 94%, PPV of 25%, LR+ of 3.11 and LR- of 0.65. Conclusions: ST-segment depression could be associated with non-calcified plaques in patients without coronary artery calcifications, even with normal exercise stress myocardial perfusion or wall motion (non-obstructive disease).

Usefulness of 18F-Fluorocholine Positron Emission Tomography-Computed Tomography in Locating Lesions in Hyperparathyroidism: A Systematic Review.

IMPORTANCE: Identifying parathyroid glands correctly before a surgical procedure is essential to perform minimally invasive surgery. First-line tests with discordant or negative results underscore the need for more accurate imaging tests, thus decreasing the requirement for bilateral neck exploration or reintervention. OBJECTIVE: To review the available evidence to determine positive predictive value, negative predictive value, sensitivity, and specificity in clinical cases in which 18F-fluorocholine positron emission tomography-computed tomography (PET/CT) could be useful as a method to locate the lesions, and the benefits and controversial aspects of the method. EVIDENCE REVIEW: A search was conducted using the PubMed Central and Cochrane Library databases for studies published in English from July 26, 2014, to November 30, 2018, using the search terms 18 choline, 18F choline, 18F-choline, 18 fluorocholine PET CT, hyperparathyroidism, primary hyperparathyroidism, secondary hyperparathyroidism, tertiary hyperparathyroidism, persistent hyperparathyroidism, recurrent hyperparathyroidism, ectopic hyperparathyroidism, and parathyroid adenoma. Other inclusion criteria were reporting at least 1 of the following measurements: negative or positive predictive value, sensitivity, and specificity of 18F-fluorocholine PET/CT in the diagnosis of hyperparathyroidism (HPT). Exclusion criteria were language other than English, use of a tracer other than 18F-fluorocholine, reports of a single case, and studies not related to HPT. The Oxford Centre classifications for levels of evidence were used. FINDINGS: Sixteen studies fulfilled the inclusion criteria, comprising a total of 619 patients. Selected studies included 10 prospective cohort studies, 5 retrospective cohort studies, and 1 case series. Of the subtypes of HPT diagnosed using 18F-fluorocholine PET/CT, 579 were primary HPT, 22 were secondary HPT, 1 was tertiary HPT, and 7 were associated with multiple endocrine neoplasia type I. Pathologically, the neoplasms comprised 459 adenomas, 59 hyperplasia, and 19 double adenomas. CONCLUSIONS AND RELEVANCE: 18F-fluorcholine PET/CT may be indicated when results of first-line tests are negative or discordant and in challenging clinical situations where locating the source of HPT is difficult.

Utilidad de la 18f-colina pet/tc en hiperparatiroidismo primario persistente o recurrente: experiencia inicial / Usefulness of 18f-choline pet / tc in persistent or recurrent primary hyperparathyroidism: initial experience

El hiperparatiroidismo persistente/recurrente representa un desafío en la localización del tejido paratiroideo hiperfuncionante. En esta subpoblación, los métodos convencionales ofrecen un menor rédito diagnóstico. La 18F-colina PET/TC podría ser una buena alternativa dada su mejor resolución espacial, capacidad de detectar glándulas ectópicas y la conjunción de la imagen molecular y anatómica. Sin embargo, la evidencia en este subgrupo de pacientes es escasa. Objetivo: evaluar la utilidad de la 18F-colina PET/TC como método de localización en el hiperparatiroidismo persistente o recurrente. Materiales y métodos: se analizaron los pacientes con 18F-colina PET/TC para hiperparatiroidismo entre diciembre de 2015 y enero de 2018 en un centro terciario de alto volumen. Se analizaron el número de lesiones, su localización, tamaño y el Standard Uptake Value máximo (SUV max) en las imágenes tempranas y tardías. Se compararon los resultados con los métodos convencionales. Resultados: 7 de 15 pacientes habían sido operados previamente (persistentes/recurrentes). La 18F-colina PET/TC detectó 6/7 casos (83,33%), la ecografía cervical 1/4 (25%) y el SPECT de paratiroides y la resonancia nuclear magnética 2/5 (40%). El SUV max obtenido fue variable, en la mitad de los casos a los 10 minutos y en los restantes a la hora; el tamaño promedio de las lesiones fue 8,61 mm (6-12 mm). Conclusiones: la 18F-colina PET/TC muestra una alta tasa de detección en los pacientes con hiperparatiroidismo persistente/recurrente. La combinación del comportamiento biológico del PET con los hallazgos morfológicos aportados por la TC con contraste endovenoso le ofrecería ventajas sobre otros estudios que podrían posicionarlo como método de primera línea en esta subpoblación. (AU)

Persistent or recurrent hyperparathyroidism represents a challenge regarding the localization of the hyper-functioning parathyroid tissue. In this subpopulation of hyperpharathyroid patients, conventional methods have a low diagnostic yield. The 18F-choline PET /CT could be a good alternative given its better spatial resolution, ability to detect ectopic glands, and the conjunction of the molecular and anatomical image. However, the evidence in this subgroup of patients is limited. Objective: to evaluate the utility of 18F-choline PET/ CT as a localization method in persistent or recurrent hyperparathyroidism. Materials and methods: patients with 18F-choline PET / CT for hyperparathyroidism between December 2015 and January 2018 in a high-volume tertiary center were included. The number of lesions, and their location, size, and maximum Standard Uptake Value (SUV) in the early and late images were analyzed. The results were compared to conventional methods. Results: 7 of 15 patients had been previously operated (persistent/recurrent). 18F-choline PET / CT detected 6/7 cases (83,33%), cervical ultrasound 1/4 (25%) and parathyroid SPECT and magnetic resonance 2/5 (40%). The maximum SUV was variable, one half at 10 minutes and the other half at 60 minutes; the average size of the lesions was 8.61 mm (6-12 mm). Conclusions: 18F-Choline PET / CT shows a high detection rate in patients with persistent / recurrent hyperparathyroidism. The combination of the biological behavior of PET with the morphological findings provided by CT with intravenous contrast would offer advantages over other studies that could position it as a first line method in this subpopulation. (AU)

Interstage Assessment of Remnant Liver Function in ALPPS Using Hepatobiliary Scintigraphy: Prediction of Posthepatectomy Liver Failure and Introduction of the HIBA Index.

OBJECTIVE: The aim of this study was to evaluate interstage liver function in associating liver partition and portal vein occlusion for staged hepatectomy (ALPPS) using hepatobiliary scintigraphy (HBS) and whether this may help to predict posthepatectomy liver failure (PHLF). BACKGROUND: ALPPS remains controversial given the high rate of liver-related mortality after stage 2. HBS combined with single photon emission computed tomography (SPECT) accurately estimates future liver remnant function and may be useful to predict PHLF. METHODS: Between 2011 and 2016, 20 of 39 patients (51.3%) underwent SPECT-HBS before ALPPS stage 2 for primary (n = 3) or secondary liver tumors (n = 17) at the Hospital Italiano de Buenos Aires (HIBA). PHLF was defined by the International Study Group of Liver Surgery criteria, 50-50 criteria, or peak bilirubin >7 mg/dL. Grade A PHLF was excluded, as it requires no change in clinical management. Receiver-operating characteristic curves were used to determine cutoff for HBS parameters. RESULTS: Interstagely, 3 HBS parameters differed significantly between patients with (n = 4) and without PHLF (n = 16) after stage 2. Among these, the HIBA-index best predicted PHLF, with a cutoff value of 15%. The risk of PHLF in patients with cutoff <15% was 80%, whereas no patient with cutoff ≥15% developed PHLF. CONCLUSIONS: Interstage HBS could help to predict clinically significant PHLF after ALPPS stage 2. An HIBA-index cutoff of 15% seemed to give the best diagnostic performance. Although further studies are needed to confirm our findings, the routine application of this noninvasive low-cost examination could facilitate decision-making in institutions performing ALPPS.

Ventricular-arterial coupling assessment using gated single-photon emission computed tomography: relationship with reserve pulse pressure and repolarization abnormalities.

AIMS: In patients with normal myocardial perfusion, ST-segment depression and reserve pulse pressure (rPP) can identify patients at higher risk of cardiovascular events. We aimed to explore the prevalence of impaired ventricular-arterial coupling (VAc) in patients with normal myocardial perfusion imaging and its relationship with ST-segment depression and rPP. METHODS AND RESULTS: The present study included consecutive patients with normal myocardial perfusion imaging by single-photon emission computed tomography and ST-segment depression. Stroke volume, end-systolic pressure, arterial elastance (Ea), ventricular elastance (Ev), and VAc (Ea/Ev) were estimated both at rest and during stress. The difference between stress and rest (ΔVAc) was calculated. A positive ΔVAc was considered an impaired ΔVAc (iVAc). RESULTS: A total of 92 patients were prospectively included. iVAc was identified in 44 (59%) patients with ST-segment depression compared with 3 (16%) patients with normal repolarization (P=0.001). A higher incidence of abnormal rPP was identified in patients with ST-segment depression compared with the control group (61 vs. 16%, P=0.0001). ST-segment depression was identified as the only independent predictor of iVAc (adjusted OR 7.5; 95% CI 1.9-30.0, P=0.004). CONCLUSION: Noninvasive assessment of VAc is feasible with gated single-photon emission computed tomography and appears to be related to ST-segment depression and reserve rPP.

Use of nebivolol for the treatment of endothelial dysfunction in patients with hypertension: the EDEN registry.

This aim of this study was to evaluate the presence of endothelial dysfunction in patients with primary hypertension and to determine the usefulness of nebivolol, a selective beta-adrenoceptor blocking agent, as a potential treatment for endothelial dysfunction. Of 176 patients with stage I hypertension, 36 patients (20%), the majority of whom were overweight/obese, were found to have abnormal results with myocardial perfusion single-photon emission computed tomography (MP-SPECT) under cold pressor test conditions. These 36 patients were treated for 28 days with 5 mg/d nebivolol, after which only 3 (8.3%) still had abnormal MP-SPECT results. The mean ischemia score was consistent with moderate risk and decreased significantly after treatment with nebivolol. All hemodynamic variables measured (systolic and diastolic blood pressure and heart rate) were also reduced significantly by treatment with nebivolol. Endothelial dysfunction plays a key role in the pathogenesis of atherosclerosis and its reversal has considerable implications for clinical outcomes in affected patients. The cold pressor testing results of this study suggest that nebivolol may have beneficial anti-ischemic effects in the coronary arteries of patients with hypertension. However, these findings need to be confirmed in larger randomized controlled trials, ideally comparing nebivolol with other blood pressure lowering agents or NO synthase inhibitors.