Respiratory Displacement of the Right Adrenal Vein: Comparison of Inspiratory and Expiratory Computed Tomography With Catheter Venography.

OBJECTIVE: The aim of the study is to reveal the respiratory displacement of the right adrenal vein (RAV) to predict the exact location of the RAV during adrenal venous sampling (AVS). METHODS: Computed tomography (CT) scans obtained 45 seconds (breath-hold at inhalation) and 70 seconds (breath-hold at exhalation) after contrast material injection were compared to venograms of the RAV of patients with primary aldosteronism who underwent AVS between January 2016 and December 2020. The craniocaudal distance between the center of the Th11/12 disc and the RAV orifice was measured; the craniocaudal location of the RAV orifice was also specified relative to vertebral bodies and intervertebral discs on inspiratory phase CT (In-CT), expiratory phase CT (Ex-CT), and catheter venography. The transverse and vertical angles of the RAV and the position of the RAV orifice on the inferior vena cava (IVC) circumference were measured on In-CT and Ex-CT. RESULTS: In total, 51 patients (30 males, 21 females; mean age, 54.9 ± 11.1 years) were included. Craniocaudal distances between the center of the Th11/12 disc and RAV orifice were significantly different among the following 3 acquisitions: catheter venography versus In-CT (15.2 ± 8.4 mm); venography versus Ex-CT (5.6 ± 4.1 mm); and In-CT versus Ex-CT (19.6 ± 8.0 mm) (all, P < 0.001). The craniocaudal location of the RAV orifice on venography was significantly closer to that on Ex-CT than on In-CT (P < 0.001); measurements using venograms compared with In-CT and Ex-CT scans were within 1 level difference in 18 (35.3%) and 47 (92.2%) patients, respectively (P < 0.001). The vertical angle of the RAV was significantly more likely to be smaller on In-CT than on Ex-CT (P < 0.001). CONCLUSIONS: RAV locations and angles change with respiratory motion. It is crucial to consider the respiratory phase of CT because it can enable a more accurate prediction of the location of the RAV during AVS.

Prediction of Anemia From Cerebral Venous Sinus Attenuation on Deep-Learning Reconstructed Brain Computed Tomography Images.

OBJECTIVE: The aim of the study is to evaluate whether the prediction of anemia is possible using quantitative analyses of unenhanced cranial computed tomography (CT) with deep learning reconstruction (DLR) compared with conventional methods. METHODS: This cross-sectional retrospective study included 116 participants (76 males; mean age, 66.7) who had hemoglobin (Hb) levels obtained within 24 hours of unenhanced cranial CT, which included 2 reconstruction methods: DLR and hybrid iterative reconstruction. Regions of interest were the confluence of sinuses (CoS) and the right and left transverse sinuses. In addition, edge rise distance of cerebrospinal fluid and venous was measured. RESULTS: Spearman rank correlation coefficient demonstrated a positive association between Hb levels and sinus attenuation values. Among these, the CoS in DLR had the best correlation ( r = 0.703, P < 0.001). For the prediction of anemia (Hb < 11 g/dL), the area under the curve of CoS in DLR (area under the curve = 0.874; 95% confidence interval, 0.798-0.949; P < 0.001) was the highest; however, there were no significant differences among reconstruction method and sinus. The attenuation values of DLR were significantly higher than those of hybrid iterative reconstruction ( P < 0.001, paired t test), and the differences between the 2 methods were 4.1 (standard deviation [SD], 1.6) for CoS, 5.2 (SD, 2.2) for right transverse sinuses, and 5.8 (SD, 2.4) for left transverse sinuses. The signal-to-noise ratio ( P < 0.001, paired t test) and edge rise distance ( P < 0.001, Wilcoxon signed rank test) of DLR was significantly higher. CONCLUSIONS: Higher CT attenuation values should be considered for predicting anemia based on brain DLR images.

Optimizing simulated interviews and feedback to maximize medical students' self-efficacy in real time.

BACKGROUND: Self-efficacy is crucial in improving medical students' communication skills. This study aims to clarify where medical students' self-efficacy is greatest following an interview with a simulated patient and subsequent feedback. METHODS: A total of 162 medical students (109 men, 53 women) in their fourth or fifth year at a university in Japan participated in this study. The degree of self-efficacy in medical interviewing was measured before and after a medical interview with a simulated patient, and after the subsequent feedback session. RESULTS: ANOVA analysis revealed that self-efficacy for medical interviews was higher after both the interview and the feedback session than before the interview. Among all three time points, self-efficacy was highest after the feedback session. CONCLUSIONS: Feedback following a simulated interview with a simulated patient is important to improve the self-efficacy of medical students when learning medical interviewing skills.

Usefulness of Model-Based Iterative Reconstruction in Brain CT as Compared With Hybrid Iterative Reconstruction.

OBJECTIVE: The aim of this study was to compare the contrast of gray to white matter between forward-projected model-based iterative reconstruction solution (FIRST) and hybrid iterative reconstruction (IR) by measuring computed tomography value of brain parenchyma. METHODS: Computed tomography values of the gray and white matter in 15 areas of 21 patients (7 males, 14 females; average age, 49.5 ± 10.7 years) were measured and compared between FIRST and hybrid IR with filtered back projection (FBP) using 2 different reconstruction kernels FC21 and FC26. RESULTS: The ratio of gray to white matter obtained using FIRST (1.25 ± 0.08) was significantly higher than that obtained using FBP with both kernel FC21 (1.13 ± 0.03) and kernel FC26 (1.22 ± 0.06). CONCLUSIONS: FIRST increases the contrast between the gray and white matter, and decreases noise in brain computed tomography compared with FBP with hybrid IR.

Detectability of Malignant Lesions by Whole-Body Magnetic Resonance Imaging Using Whole-Body Integrated Positron Emission Tomography/Magnetic Resonance Imaging.

PURPOSE: To assess the diagnostic ability of whole-body magnetic resonance imaging (MRI) using integrated positron emission tomography/MRI(PET/MRI). METHODS: Axial T2-weighted image (T2WI), diffusion-weighted imaging (DWI), coronal T1-weighted image (T1WI), axial volumetric interpolated breath-hold examination in the lung field, and 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG-PET) were evaluated in combination with T2WI alone, T2WI + DWI, T2WI + DWI + T1WI, T2WI + DWI + T1WI + volumetric interpolated breath-hold examination (all MRI images), and all MRI + FDG-PET. RESULTS: A total of 370 lesions were observed in 90 (62.5%) of the 144 patients. The lesion-based sensitivities were 62%, 74%, 74%, 76%, and 94%, and the patient-based sensitivities were 70%, 77%, 77%, 77%, and 81% using T2WI, T2WI + DWI, T2WI + DWI + T1WI, all MRI, and all MRI + FDG-PET, respectively. There were significant differences in the lesion-based sensitivity between T2WI and other sequence combinations and between all MRI and all MRI + FDG-PET. No significant differences were observed between any combinations among the patient-based sensitivities. CONCLUSION: The sensitivity of whole-body MRI was lower when lesion based, but almost equivalent when patient based compared with PET/MRI.

Impact of iodine contrast media on gamma camera-based GFR and factors affecting the difference between serum creatinine-based estimated GFR and Gate's GFR.

OBJECTIVE: We aimed to elucidate the factors underlying the difference between estimated glomerular filtration rate (eGFR) calculated from serum creatinine and Gate's GFR (gGFR) measured using technetium-99m diethylene triamine pentaacetic acid ( 99m Tc-DTPA) scintigraphy. METHODS: This study was based on consecutive patients who underwent 99m Tc-DTPA scintigraphy at our hospital between January 2021 and December 2022 and whose blood serum creatinine data were obtained on the same day as the 99m Tc-DTPA scintigraphy. Relationships between the ratio of gGFR and eGFR (gGFR/eGFR) and age, sex, BMI, visceral fat, psoas muscle index (PMI), serum blood urea nitrogen, and creatinine level were investigated based on 75 patients. Additionally, for 44 patients who had two or more follow-up DTPA studies, we compared gGFR values for studies that used iodine contrast media (ICM) for computed tomography before same-day 99m Tc-DTPA studies and those that did not in the same patients. RESULTS: Weak correlations were observed between gGFR/eGFR and PMI ( r  = 0.30), BMI ( r  = 0.24), and the visceral fat area ( r  = 0.33). Multi-regression analyses showed that gGFR/eGFR was correlated with PMI ( ß â€…= 0.34, P  < 0.01) and approached significance with the visceral fat area ( ß â€…= 0.24, P  = 0.05). A significant difference was observed in gGFR between patients who received ICM before the 99m Tc-DTPA renogram and those who did not ( P  < 0.001, eGFR 80.5 ±â€…19.0 vs. 91.7 ±â€…27.8 ml/min). CONCLUSION: ICM administration temporarily decreased gGFR, and increased muscle mass increased the difference between eGFR and gGFR values.

Investigation of tumor assessment between two PET systems using various indices: comparison between PET/CT and PET/MRI systems.

This study aimed to determine the comparability of tumor-uptake indices of 18F-FDG in positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance imaging (PET/MRI). 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) PET/CT and PET/MRI were performed on 55 patients with confirmed primary malignancies. PET/CT preceded PET/MRI in all examinations. Accumulation of 18F-FDG in lesions and normal organs (brain, liver) was measured. Maximum and peak standardized uptake values (SUVs; SUVmax and SUVpeak, respectively), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) with margin thresholds of SUV of 50% (MTV50%; TLG50%, respectively) were measured as indices for comparison of measurements in tumors. Comparative indices with tumor SUVmax and liver ratio (TLRmax), brain ratio (TBRmax) were calculated. These indices were compared between PET/CT and PET/MRI examinations. The data measured using PET/CT and PET/MRI showed significant correlations for all tumor indices. The correlation was strongest for SUVpeak (r = 0.933), followed by TBRmax (r = 0.929); and the index ratio of (PET/CT)/(PET/MRI) data was close to 1.0 for TLRmax (1.00 ± 0.22) and TBRmax (1.01 ± 0.21), followed by MTV50% (0.82 ± 0.33) and TLG50% (1.18 ± 0.45). The values of all indices showed strong correlations between PET/CT and PET/MRI examinations. Among them, TLRmax, TBRmax, MTV50%, and TLG50% showed a close value and may be useful for comparison of tumor evaluation between two PET systems.

Conventional versus aspiration-type needles in CT-guided biopsy for chest pathologies/lesions: A comparative study.

BACKGROUND: Larger sample volume can be obtained in one needle pass using an aspiration-type semi-automatic cutting biopsy needle (STARCUT® aspiration-type needle; TSK Laboratory, Tochigi, Japan) in comparison to the conventional semi-automatic cutting biopsy needle. OBJECTIVE: To evaluate and compare the safety and effectiveness of aspiration-type semi-automatic cutting biopsy needles and non-aspiration-type biopsy needles when performing computed tomography (CT)-guided core needle biopsies (CNBs). METHODS: A total of 106 patients underwent CT-guided CNB for chest lesions between June 2013 and March 2020 at our hospital. Non-aspiration-type cutting biopsy needles were used in 47 of these patients, while aspiration-type needles were used in the remaining 59 patients. All needles used were 18- or 20-gauge biopsy needles. Parameters, like forced expiratory volume in 1-second percent (FEV1.0%), the maximum size of the target lesion, puncture pathway distance in the lung, number of needle passes, procedure time, diagnostic accuracy, and incidence of complications, were measured. Comparisons were made between the needle-type groups. RESULTS: No significant difference was observed in terms of diagnostic accuracy. However, the procedure time was shorter and a lesser number of needle passes were required with the aspiration-type cutting biopsy needle compared to the non-aspiration-type needle. Pneumothorax and pulmonary hemorrhage were the complications encountered, however, their incidence was not significantly different between the two types of needles. CONCLUSIONS: The aspiration-type semi-automatic cutting biopsy needle had similar diagnostic accuracy as the non-aspiration-type biopsy needle, with added advantages of a lesser number of needle passes and shorter procedure time.

Different prognostic outcomes in two cases of FDG-PET/CT-Positive and -negative cardiac angiosarcoma.

Cardiac angiosarcoma is a rare malignant tumor with a poor prognosis, characterized by the high uptake of 18F-fluorodeoxyglucose (FDG). This case report presents two cases of cardiac angiosarcoma with a marked difference in FDG uptake and prognosis.Case Summary:Case 1: A 40-year-old male presented with syncope. Ultrasound echocardiography demonstrated a cardiac tumor with a high uptake of 18F-FDG (maximum standardized uptake value=9.2). The patient underwent heart catheterization and tumor biopsy. The pathological result was high-grade angiosarcoma, and the MIB-1(Ki-67) proliferation index was approximately 20%. Systemic chemotherapy was administered; however, the patient died 2 years and 5 months after disease onset.Case 2: A 65-year-old female had a right atrial tumor incidentally diagnosed during routine ultrasound echocardiography. The tumor exhibited a low uptake of 18F-FDG (maximum standardized uptake value=1.8). Open heart surgery was performed, and the tumor was completely resected. Histological analysis revealed low-grade angiosarcoma, and the MIB-1(Ki-67) proliferation index was less than 5%. The patient was followed-up and had not relapsed 2 years after surgery.Conclusion: 18F-FDG uptake may reflect pathological tumor grade and prognosis in cardiac angiosarcoma.

Nonconvulsive Status Epilepticus Caused by Cerebrospinal Fluid Dissemination of a Salivary Duct Carcinoma: A Case Report.

Salivary duct carcinoma (SDC) is a rare and highly aggressive salivary gland tumor with rapid growth, distant metastasis, and a high recurrence rate. Moreover, the parotid gland is the most common site with a poor prognosis. A lower frequency of distance metastasis to the liver, skin, and brain has also been reported, although the lungs, bones, and lymph nodes are the most common sites of SDC metastasis. We report a case of nonconvulsive status epilepticus (NCSE) in a 73-year-old male comatose patient having SDC of the parotid gland with an unusual metastasis to the skin and brain diagnosed by frequent cerebrospinal fluid examinations. Meningeal carcinomatosis usually has a poor prognosis, and NCSE is a reversible cause of altered mentation. Clinicians should know the unique set of epilepsy etiologies in patients with malignant tumors.

Three cases of organized hematoma of the maxillary sinus in patients who underwent preoperative arterial embolization.

Organized hematoma (OH) is benign tumor in the maxillary sinus. The standard treatment for OH is complete surgical resection, however massive bleeding can occur during the procedure, albeit rarely. Some reports have suggested preoperative embolization is useful for reducing the volume of intraoperative bleeding. We report 3 cases of OH in the maxillary performed preoperative embolization. We identified the feeding arteries by angiography or IVR-CT, and we embolized them using Gelatin sponge particles. The embolized artery was the maxillary artery or both the maxillary and the facial artery. There were no major complications as a result of embolization. The mean fluoroscopy time was 35.8 minutes, and the mean fluoroscopy dose was 329.3 mGy. Tumor resection was performed the next day after arterial embolization. The mean bleeding volume for surgery was 383.3 ml, and the mean operative time was 194 minutes. No recurrence was observed in any of the cases over a 4-year follow-up period. We considered that it is possible that preoperative artery embolization is useful for decreasing intraoperative bleeding volume. Although the methods and usefulness of embolization await future reports, it is a technique that should be considered preoperatively because of its potential to prevent massive bleeding.

Rupture of Renal Artery Aneurysm in a Patient with Granulomatosis with Polyangiitis.

Granulomatosis with polyangiitis (GPA) is the systemic vasculitis affecting predominantly small vessels, but vasculitis of medium size artery can be associated. We treated a patient with GPA who had hemorrhagic instability because of a rupture of an aneurysm in the branch of the renal artery; the patient underwent arterial embolization (AE), and hemostasis was successfully achieved. Literature reviews were conducted on the basis of the data available on PubMed, and seven published reports of eight cases with renal artery aneurysms were identified. We concluded that emergency physicians should be aware of the existence of renal artery aneurysms associated with GPA. AE should be considered as one of the treatment choices whenever renal bleeding takes place.

Paradoxical Cerebral Embolization Caused by Thrombus-In-Transit via a Patent Foramen Ovale in a Patient with Symptomatic Pulmonary Embolism: A Case Report.

Objective: Acute pulmonary embolism (PE) is a life-threatening cardiovascular event associated with high mortality and morbidity. The presence of a patent foramen ovale (PFO) in patients with acute PE represents a risk factor for mortality. Furthermore, a thrombus-in-transit via a PFO with impending paradoxical embolism carries a high mortality rate. Case Presentation: An adult patient with ischemic stroke caused by paradoxical embolism following PE underwent mechanical thrombectomy and achieved successful recanalization. Initial CT pulmonary angiography (CTPA) showed not only pulmonary thromboemboli but also bilateral atrial thromboemboli. During hospitalization, transesophageal echocardiography (TEE) revealed the PFO with a right-to-left shunt. Two months after rehabilitation undergone by the patient, PE completely disappeared and PFO closure was conducted to reduce the recurrence risk of ischemic stroke. Conclusion: Not only cardiologists but also interventional neurologists should understand that CTPA can demonstrate the thrombus-in-transit through the PFO and provides a reliable prediction of the sudden onset of ischemic stroke in patients with symptomatic PE. When identified, considering a case-by-case treatment approach by multidisciplinary teams is essential for preventing further life-threatening paradoxical embolization.

Optimized workflow and imaging protocols for whole-body oncologic PET/MRI.

Although PET/MRI has the advantages of a simultaneous acquisition of PET and MRI, high soft-tissue contrast of the MRI images, and reduction of radiation exposure, its low profitability and long acquisition time are significant problems in clinical settings. Thus, MRI protocols that meet oncological purposes need to be used in order to reduce examination time while securing detectability. Currently, half-Fourier acquisition single-shot turbo spin echo and 3D-T1 volumetric interpolated breath-hold examination may be the most commonly used sequences for whole-body imaging due to their shorter acquisition time and higher diagnostic accuracy. Although there have been several reports that adding diffusion weighted image (DWI) to PET/MRI protocol has had no effect on tumor detection to date, in cases of liver, kidney, bladder, and prostate cancer, the use of DWI may be beneficial in detecting lesions. Another possible option is to scan each region with different MRI sequences instead of scanning the whole body using one sequence continuously. We herein report a workflow and imaging protocols for whole-body oncologic PET/MRI using an integrated system in the clinical routine, designed for the detection, for example by cancer screening, of metastatic lesions, in order to help future users optimize their workflow and imaging protocols.