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.

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.

Coil embolization of a celiac artery pseudoaneurysm under balloon-assisted flow control: A case report.

Coil migration can occur when coil embolization is used for treating pseudoaneurysms associated with large arteries. The double microcatheter technique is useful for preventing coil migration; the balloon catheter can reduce blood flow and active bleeding upon balloon inflation, and can also compress the bleeding point and arrest bleeding temporarily. We report a case describing the management of a pseudoaneurysm with coil embolization using double microcatheters and a balloon catheter to control blood flow and prevent coil migration. A 73-year-old male patient presented with a pseudoaneurysm of the celiac artery arising from the splenic artery stump following surgery. Coil embolization of the pseudoaneurysm using a double microcatheter embolization technique with a balloon catheter was considered. A balloon catheter was inserted into the celiac artery and active bleeding was temporarily arrested with the inflated balloon. First, a microcatheter was inserted into the balloon catheter, and another microcatheter was placed in the celiac artery. An electrical detachable coil was inserted into the proximal common hepatic artery just distal to the pseudoaneurysm. The second electrically detachable coil was inserted while the first coil remained attached. After detachment of the second coil, additional electrically detachable coils were inserted for similar embolization. The balloon was gradually deflated. Finally, the first coil was detached and we confirmed absence of the bleeding. Our case report demonstrated that a balloon catheter can control the flow vessels, and the double microcatheter embolization technique with a balloon catheter is useful for coil embolization in high-flow or large vessels.

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.

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.

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.