[18F]F-Choline PET/CT and 4D-CT in the evaluation of primary hyperparathyroidism: rivals or allies?

Primary hyperparathyroidism is a hard-to-diagnose condition that can run without symptoms for many years without causing symptoms; yet, it can cause dire long-term consequences, such as osteoporosis and renal impairment. First-line diagnostic methods include ultrasound and parathyroid scintigraphy, which provide unsatisfactory results in terms of detection rate. Second-line imaging methods include [18F]F-Choline PET/CT, 4D-CT, and their combination. These methods have shown a great detection rate and sensitivity; however, they are to this day less widespread than the first-line ones. Both the two methods (PET and 4D-CT) have their specific advantages and field of application, as well as their specific limitations. In this narrative review, we will describe the advantages and disadvantages of the two techniques extensively. Moreover, we will try to identify whether the combined examination can play a role and how relevant this role is. Finally, we will try to define the specific clinical situation in which each method can provide the best contribution to diagnosing parathyroid tissue hyperfunction.

Effect of Aging on Deferasirox Therapy in Transfusion-dependent Patients. A prospective-retrospective, cohort-study.

BACKGROUND: Iron-chelation therapy is life-saving in patients on a chronic transfusion regimen as it reduces organ damage related to iron deposition in the tissues. Deferasirox, an iron-chelator, is characterized by pharmacokinetics variability, and some patients may discontinue the treatment due to toxicities. OBJECTIVE: Understanding whether deferasirox plasma levels are related to patients' specific characteristics could help optimize DFX dosage. METHODS: We analyzed deferasirox plasma concentration in 57 transfusion-dependent anemic patients using the HPLC method in this prospective-retrospective cohort study. All outpatients (3 to 98 years) were treated with deferasirox (film-coated tablet) for at least one year (median dose, 16.5 mg/Kg once a day). Deferasirox plasma concentration was normalized for dose/Kg (C/dose) and corrected with a linear regression model that relates C/dose and the time of blood sampling (Cref/dose). RESULTS: No significant differences in Cref/dose were found between males and females, either between different types of hemoglobinopathies or depending on the presence of the UGT1A1*28 polymorphism. Cref/dose has a positive and significant correlation with age, creatinine, and direct bilirubin. Cref/dose, instead, has a negative and significant correlation with Liver Iron Concentration (LIC), ferritin, and eGFR. Cref/dose was significantly different between three age categories <18yrs, 18-50yrs, and >50yrs, with Cref/dose median values of 1.0, 1.2, and 1.5, respectively. CONCLUSION: The study evidenced that to ensure the efficacy of deferasirox in terms of control over LIC and, at the same time, a lesser influence on renal function, the dose of the drug to be administered to an elderly patient could be reduced.

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.

Will 18F-fluorocholine PET/CT replace other methods of preoperative parathyroid imaging?

INTRODUCTION: Primary hyperparathyroidism (PHPT) is a common endocrine disorder usually due to hyperfunctioning parathyroid glands (HPs). Surgical removal of the HPs is the main treatment for PHPT, making the correct detection and localization of HPs crucial to guiding targeted and minimally invasive surgical treatment in patients with PHPT. To date, different imaging methods have been used to detect and localize HPs, including radiology, nuclear medicine, and hybrid techniques. METHODS: The present work discusses the role and value of different imaging methods in PHPT and, particularly, evaluates the potential role of 18F-fluorcholine PET/CT as a "one-stop-shop" method for preoperative parathyroid localization in patients with PHPT. DISCUSSION: Cervical ultrasound (US) and parathyroid scintigraphy using 99mTc-MIBI are the most commonly employed methods in clinical practice. More recently, four-dimensional computed tomography (4D CT) and positron emission tomography (PET) with radiolabeled choline have emerged as useful alternatives in cases of negative or discordant findings from first-line imaging methods. CONCLUSIONS: Due to the excellent diagnostic performance of radiolabeled choline PET/CT and the low radiation burden, this technique seems to be an ideal candidate to substitute current imaging procedures including US, MIBI scintigraphy, 4D CT and MRI and perform a fast and reliable "one-stop-shop" preoperative localization of HP in patients with PHPT, including challenging cases of postoperative persistent/recurrent disease.

COVID-19 in a Patient with ß-Thalassemia Major and Severe Pulmonary Arterial Hypertension.

We here report the successful recovery from coronavirus disease-19 (COVID-19) pneumonia in a patient with ß-thalassemia major (ß-TM) and severe pulmonary arterial hypertension (PAH), focusing on the patient's comorbidities, therapeutic course and drug interaction.

Evaluation of novel coronavirus disease (COVID-19) using quantitative lung CT and clinical data: prediction of short-term outcome.

BACKGROUND: Computed tomography (CT) enables quantification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, helping in outcome prediction. METHODS: From 1 to 22 March 2020, patients with pneumonia symptoms, positive lung CT scan, and confirmed SARS-CoV-2 on reverse transcription-polymerase chain reaction (RT-PCR) were consecutively enrolled. Clinical data was collected. Outcome was defined as favourable or adverse (i.e., need for mechanical ventilation or death) and registered over a period of 10 days following CT. Volume of disease (VoD) on CT was calculated semi-automatically. Multiple linear regression was used to predict VoD by clinical/laboratory data. To predict outcome, important features were selected using a priori analysis and subsequently used to train 4 different models. RESULTS: A total of 106 consecutive patients were enrolled (median age 63.5 years, range 26-95 years; 41/106 women, 38.7%). Median duration of symptoms and C-reactive protein (CRP) was 5 days (range 1-30) and 4.94 mg/L (range 0.1-28.3), respectively. Median VoD was 249.5 cm3 (range 9.9-1505) and was predicted by lymphocyte percentage (p = 0.008) and CRP (p < 0.001). Important variables for outcome prediction included CRP (area under the curve [AUC] 0.77), VoD (AUC 0.75), age (AUC 0.72), lymphocyte percentage (AUC 0.70), coronary calcification (AUC 0.68), and presence of comorbidities (AUC 0.66). Support vector machine had the best performance in outcome prediction, yielding an AUC of 0.92. CONCLUSIONS: Measuring the VoD using a simple CT post-processing tool estimates SARS-CoV-2 burden. CT and clinical data together enable accurate prediction of short-term clinical outcome.

Diagnostic value of retrospectively fused 64CuCl2 PET/MRI in biochemical relapse of prostate cancer: comparison with fused 18F-Choline PET/MRI, 64CuCl2 PET/CT, 18F-Choline PET/CT, and mpMRI.

PURPOSE: To assess the diagnostic value of retrospectively fused PET/MRI by comparing the detection rates (DRs) of fused 64CuCl2 PET/MRI vs. fused 18F-Choline PET/MRI in patients with suspected prostatic cancer (PCa) recurrence. The secondary objective was to compare the DRs of fused PET/MRI vs. those of the separate imaging modalities. METHODS: We retrospectively evaluated 50 PCa patients with biochemical relapse after radical prostatectomy (RP) or radiotherapy (RT). All patients underwent 64CuCl2 PET/CT, 18F-Choline PET/CT, and multiparametric magnetic resonance imaging (mpMRI) within 15 days. Fused 64CuCl2-PET/MRI and fused 18F-Choline PET/MRI images were obtained by retrospective co-registration of MRI and PET images. Experienced readers interpreted the images, and the DRs of each imaging modality were assessed. RESULTS: In the patient-based analysis, overall DRs of fused 64CuCl2 PET/MRI, fused 18F-Choline PET/MRI, 64CuCl2 PET/CT, 18F-Choline PET/CT, and mpMRI were 88%, 68%, 82%, 56%, and 74%, respectively. In the lesion-based analysis, overall DRs of fused 64CuCl2 PET/MRI, fused 18F-Choline PET/MRI, 64CuCl2 PET/CT, 18 F-Choline PET/CT, and mpMRI were 95%, 66%, 87%, 58%, and 71%, respectively. CONCLUSIONS: Retrospectively fused PET/MRI is able to overcome the limitations of the separate interpretation of the individual imaging modalities. Fused 64CuCl2 PET/MRI provided the highest diagnostic performance in the detection of PCa local relapse.

Noninvasive liver fibrosis assessment in chronic viral hepatitis C: agreement among 1D transient elastography, 2D shear wave elastography, and magnetic resonance elastography.

PURPOSE: To assess the agreement of one-dimensional transient elastography (1D-TE), two-dimensional shear wave elastography (2D-SWE), and magnetic resonance elastography (MRE) in a consecutive cohort of patients affected by hepatitis C virus (HCV) and to understand which patient-related factors are associated with disagreement. METHODS: Ninety-one consecutive patients with current or previous chronic HCV infection were enrolled between March 2017 and September 2018. We assessed the correlation between stiffness measurements expressed in kilopascals (kPa). After converting kPa values in three groups of increasing fibrosis burden using validated cut-off values, we assessed the agreement among the different techniques. Factors influencing inter-modality disagreement were examined by employing multivariate logistic regression analysis. RESULTS: Seventy-seven patients met the inclusion criteria and had reliable measurements by all stiffness imaging techniques. At the quantitative analysis, a strong correlation between stiffness measurements was found (Spearman's rho values ranging from 0.7 to 0.89 in all pairs of techniques). Complete concordance among MRE, 1D-TE, and 2D-SWE was found in 64.9% of patients, and the agreement was highest between MRE and 1D-TE, with κ value of 0.801. In only 2/77 patients (2.6%), there was complete disagreement. High body mass index (BMI) was the only factor significantly associated with inter-modality discordance. CONCLUSIONS: MRE, 1D-TE, and 2D-SWE assigned the majority of patients to the same fibrosis group. The agreement was at least good, and there was a strong correlation between kPa values in all three pairs of techniques. Highest agreement was found between MRE and 1D-TE. High BMI was associated with discordance among the techniques.

[Flexible cystoscope for the treatment of urinary stones in intestinal reservoirs.] / Cistoscopia flexible para el tratamiento de las litiasis urinarias en reservorios intestinales.

OBJECTIVE: Stones are common mid- and long-term complications in urinary diversions built with bowel. However the reservoir intestinal loops can lead to difficult endoscopic approach. METHODS: We report two challenging cases with unfavourable anatomy successfully treated by gently handling a flexible cystoscope in a low pressure system. RESULTS: One patient with stones in a continent pouch was cleaned up with a grasping basket through the efferent umbilical limb. Another patient with an orthotopic ileal neobladder not accessible by rigid cystoscope due to high pelvic floor was treated with holmiun laser lithotripsy. CONCLUSIONS: Urologists should consider the versatility of flexible cystoscope to obviate the need for percutaneous lithotripsy or open lithotomy.

OBJETIVO: La aparición de litiasis es una complicación común a medio y largo plazo en las derivaciones urinarias construidas con intestino. Sin embargo, las asas intestinales de los reservorios pueden tener un acceso endoscópico difícil. METODOS: Presentamos dos casos difíciles con anatomía desfavorable tratados con éxito utilizando cuidadosamente un cistoscopio flexible en un sistema de baja presión. RESULTADOS: Un paciente con litiasis en una neovejiga continente quedó libre de litiasis utilizando una cestilla a través del asa eferente umbilical. Otro paciente con una neovejiga ileal ortotópica no accesible por cistoscopio rígido debido a un suelo pélvico elevado, fue tratado con litotricia con láser de Holmio. CONCLUSIONES: Los urólogos deben considerar la versatilidad de la cistoscopia flexible para obviar la necesidad de litotricia percutánea o litotomía abierta.

64CuCl2 PET/CT in Prostate Cancer Relapse.

Our objective was to evaluate the biodistribution, kinetics, and radiation dosimetry of 64CuCl2 in humans and to assess the ability of 64CuCl2 PET/CT to detect prostate cancer (PCa) recurrence in patients with biochemical relapse. Methods: We prospectively evaluated 50 PCa patients with biochemical relapse after surgery or external-beam radiation therapy. All patients underwent 64CuCl2 PET/CT, 18F-choline PET/CT, and multiparametric MRI within 15 d of each other. Experienced readers interpreted the images, and the detection rate (DR) of each imaging modality was calculated. Histopathology, when available; clinical or laboratory response; and multidisciplinary follow-up were used to confirm the site of disease. In parallel, biodistribution, kinetics of the lesions, and radiation dosimetry of 64CuCl2 were evaluated. Results: From a dosimetric point of view, an administered dose of 200 MBq for 64CuCl2 translated into a 5.7-mSv effective dose. Unlike 18F-choline, 64CuCl2 was not excreted or accumulated in the urinary tract, thus allowing thorough pelvic exploration. The maximum 64CuCl2 uptake at the sites of PCa relapse was observed 1 h after tracer injection. In our cohort, 64CuCl2 PET/CT proved positive in 41 of 50 patients, with an overall DR of 82%. The DRs of 18F-choline PET/CT and multiparametric MRI were 56% and 74%, respectively. The difference between the DRs of 64CuCl2 PET/CT and 18F-choline PET/CT was statistically significant (P < 0.001). Interestingly, on considering prostate-specific antigen (PSA) value, 64CuCl2 PET/CT had a higher DR than 18F-choline PET/CT in patients with a PSA of less than 1 ng/mL. Conclusion: The biodistribution of 64CuCl2 is more suitable than that of 18F-choline for exploring the pelvis and prostatic bed. The 64CuCl2 effective dose is like those of other established PET tracers. In patients with biochemical relapse and a low PSA level, 64CuCl2 PET/CT shows a significantly higher DR than 18F-choline PET/CT.

Comparison between different software programs and post-processing techniques for the MRI quantification of liver iron concentration in thalassemia patients.

PURPOSE: In magnetic resonance imaging (MRI) relaxometry, various software programs are available to perform R2* measurements and to estimate the liver iron concentration (LIC). The main objective of our study was to compare R2* LIC values, obtained with three different software programs based on specific decay models and calibration curves, with LIC estimates provided by R2-relaxometry (FerriScan). METHODS: This retrospective study included 15 patients with 15 baseline MRIs and 34 serial examinations. R2* LIC estimates were calculated using the FuncTool, CMRtools/Thalassemia Tools and Quanta Hematology programs. Longitudinal LIC changes (ΔLIC) were calculated using the subset of 34 serial MRIs. RESULTS: After Bland-Altman analysis on baseline data, Quanta Hematology, which employs the monoexponential-plus-constant fit, produced the lowest mean difference [0.01 ± 0.14 log(mg/gdw)] with the closest limits of agreement. In the longitudinal setting, Quanta Hematology again gave the lowest mean difference between R2 and R2* LIC (0.1 ± 2.6 mg/gdw). Using FerriScan as reference, the value of concordant directional ΔLIC changes was the same for all programs (27/34, 85.7 %). CONCLUSIONS: R2* LICs are higher than R2 LICs at iron levels <7 mg/gdw, while R2 LIC averages higher than R2* LIC with increasing iron load. The monoexponential-plus-constant model provided the best agreement with R2 LIC estimates.

Degree of colonic distension: intrapatient comparison between CT colonography and CT with water enema.

PURPOSE: Compare colonic distension using CT colonography (CTC) and CT with water enema (CTWE) in the same patients. METHODS AND MATERIALS: Twenty-seven patients who underwent both CTC and CTWE, considering separately supine (CTC-S) and prone (CTC-P) acquisition of CTC were included. The colon was divided into six segments, performing both a qualitative and quantitative analysis. RESULTS: Adequate distension of sigmoid colon was more frequently achieved with CTC-P and CTWE compared to CTC-S (P<.05). CTC-P and CTWE showed better distension of the left colon compared to CTC-S (P<.01 and P=.03 regarding sigmoid colon, respectively; P=.01 and P=.03 regarding descending colon, respectively). CONCLUSIONS: Computed tomography (CT) studies of the colon should be customized to fulfill the clinical query.

Comparison of computed tomography and magnetic resonance imaging in the discrimination of intraperitoneal and extraperitoneal rectal cancer: initial experience.

OBJECTIVES: To compare computed tomography (CT) and magnetic resonance imaging (MRI) in evaluation of intraperitoneal/extraperitoneal location of rectal cancers. METHODS AND MATERIALS: We assessed the identification of the anterior peritoneal reflection (APR) and the distance from the inferior edge of tumors to the anal verge and from the APR to the anal verge. RESULTS: Distances obtained with CT and MRI showed a strong correlation [Spearman's coefficient of rank correlation (rho): 0.995; P<.0001]. Magnetic resonance showed sensitivity of 100% (95% CI: 89.62-100.00%), specificity of 75% (95% CI: 20.34-95.88%), positive predictive value (PPV) of 97.14% (95% CI: 85.03-99.52%), and negative predictive value (NPV) of 100% (95% CI: 30.48-100.00%). CT showed a sensitivity of 100% (95% CI: 89.32-100.00%), specificity of 60% (95% CI: 15.40-93.51%), PPV of 94.29% (95% CI: 80.81-99.13%), and NPV of 100% (95% CI: 30.48-100.00%). CONCLUSIONS: CT demonstrated a potential supporting role in the evaluation of rectal cancer, showing a strong correlation with MRI.

Review of computed tomographic colonography from a surgeon's perspective.

New research has addressed many of the early concerns of computed tomographic colonography (CTC) and these studies are now beginning to shape clinical practices. A review of the literature demonstrates that the sensitivity of CTC in screening for large polyps (>/= 1cm) or cancers in the large intestine is as high as that of conventional optical colonoscopy, however, the sensitivity decreases with the diameter of the polyp. Despite this, CTC is well tolerated, more acceptable to patients than optical colonoscopy and therefore may improve colorectal cancer screening compliance. This review not only describes the diagnostic accuracy and sensitivity of CTC, and the evolving role of CTC as a primary colon cancer screening option, but also the recent studies that have demonstrated the additional value of CTC utilization for practicing clinicians.

Multimodality fusion imaging in abdominal and pelvic malignancies: current applications and future perspectives.

Medicine is evolving toward personalized care and this development entails the integration, amalgamation, and synchronized analysis of data from multiple sources. Multimodality fusion imaging refers to the simultaneous visualization of spatially aligned and juxtaposed medical images obtained by two or more image modalities. PET/MRI scanners and MMFI platforms are able to improve the diagnostic workflow in oncologic patients and provide exquisite images that aid physicians in the molecular profiling and characterization of tissues. Advanced navigation platforms involving real-time ultrasound are promising tools for guiding personalized and tailored mini-invasive interventional procedures on technically challenging targets. The main objective of the present essay was to describe the current applications and future perspectives of multimodality fusion imaging for both diagnostic and interventional purposes in the field of abdominal and pelvic malignancies. We also outlined the technical differences between fusion imaging achieved by means of simultaneous bimodal acquisition (i.e., integrated PET/MRI scanners), retrospective co-registration, and multimodality fusion imaging involving ultrafast or real-time imaging modalities.

Diagnostic value of MRI proton density fat fraction for assessing liver steatosis in chronic viral C hepatitis.

OBJECTIVE: To assess the diagnostic performance of a T1-independent, T2*-corrected multiecho magnetic resonance imaging (MRI) technique for the quantification of hepatic steatosis in a cohort of patients affected by chronic viral C hepatitis, using liver biopsy as gold standard. METHODS: Eighty-one untreated patients with chronic viral C hepatitis were prospectively enrolled. All included patients underwent MRI, transient elastography, and liver biopsy within a time interval <10 days. RESULTS: Our cohort of 77 patients included 43/77 (55.8%) males and 34/77 (44.2%) females with a mean age of 51.31 ± 11.27 (18-81) years. The median MRI PDFF showed a strong correlation with the histological fat fraction (FF) (r = 0.754, 95% CI 0.637 to 0.836, P < 0.0001), and the correlation was influenced by neither the liver stiffness nor the T2* decay. The median MRI PDFF result was significantly lower in the F4 subgroup (P < 0.05). The diagnostic accuracy of MRI PDFF evaluated by AUC-ROC analysis was 0.926 (95% CI 0.843 to 0.973) for S ≥ 1 and 0.929 (95% CI 0.847 to 0.975) for S = 2. CONCLUSIONS: Our MRI technique of PDFF estimation allowed discriminating with a good diagnostic accuracy between different grades of hepatic steatosis.