Deep learning reconstruction allows for usage of contrast agent of lower concentration for coronary CTA than filtered back projection and hybrid iterative reconstruction.

BACKGROUND: The demand for homogeneous and higher vascular contrast enhancement is critical to provide an appropriate interpretation of abnormal vascular findings in coronary computed tomography angiography (CTA). PURPOSE: To evaluate the effect of various contrast media concentrations (Iohexol-370, Iohexol-300, Iohexol-240) and image reconstructions (filtered back projection [FBP], hybrid iterative reconstruction [IR], and deep learning reconstruction [DLR]) on coronary CTA. MATERIAL AND METHODS: A total of 63 patients referred for coronary CTA between July and October 2021 were enrolled in this prospective study, and they randomly received one of three contrast media. CTA images were reconstructed with FBP, hybrid IR, and DLR. The CT attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated for all three images. The images were subjectively evaluated by two radiologists in terms of overall image quality, artifacts, image noise, and vessel wall delineation on a 5-point Likert scale. RESULTS: The application of DLR resulted in significantly lower image noise; higher CT attenuation, SNR, and CNR; and better subjective analysis among the three different concentrations of contrast media groups (P < 0.001). There was no significant difference in the CT attenuation of the left ventricle (P = 0.089) and coronary arteries (P = 0.072) between hybrid IR at Iohexol-300 and DLR at Iohexol-240. Furthermore, application of DLR to the Iohexol-240 significantly improved SNR and CNR; it achieved higher subjective scores compared with hybrid IR at Iohexol-300 (P < 0.001). CONCLUSION: We suggest that using DLR with Iohexol-240 contrast media is preferable to hybrid IR with Iohexol-300 contrast media in coronary CTA.

Arterio-Biliary Fistula as a Rare Life-Threatening Complication of Transjugular Intrahepatic Portosystemic Shunt: A Case Report.

A 46-year-old male with alcoholic liver cirrhosis underwent a transjugular intrahepatic portosystemic shunt (TIPS) for refractory ascites. On the 9th day after the procedure, he presented with melena and decreasing hemoglobin levels. Hemobilia due to fistula formation between the right intrahepatic bile duct and right hepatic artery was suspected on computed tomography. Angiography revealed a fistula of the small branches of the hepatic segmental arteries, and right intrahepatic bile duct was confirmed; embolization was successfully performed with a coil for the eighth segmental hepatic artery, a glue-lipiodol mixture for the fifth segmental hepatic artery, and gelfoam slurry for the right anterior hepatic artery. However, 2 days after embolization, the patient died owing to aggravated disseminated intravascular coagulopathy. When gastrointestinal bleeding occurs after TIPS, careful evaluation is immediately required, and hemobilia should be considered.

Angiographic Findings of an Isolated Meandering Pulmonary Vein: A Case Report.

A meandering pulmonary vein (MPV) is a rare pulmonary vascular anomaly characterized by an abnormal course of the pulmonary vein draining into the left atrium. We report the case of a 55-year-old female who was diagnosed with a right MPV on pulmonary angiography. Enhanced chest CT revealed a vascular structure with an abnormal course that drained into the right superior pulmonary vein in the right upper lobe, which resembled a pulmonary arteriovenous malformation (AVM). Pulmonary angiography performed to discriminate between an MPV and pulmonary AVM showed no feeding artery, normal parenchymal staining, and drainage to the left atrium via the culprit vessel. Thus, the patient was diagnosed with MPV. When an MPV is difficult to differentiate from other vascular anomalies on enhanced chest CT, pulmonary angiography can be helpful. By recognizing the angiographic findings of an MPV, unnecessary treatment can be prevented.

Clinical Outcomes of the Seal® Thoracic Stent Graft for Traumatic Aortic Injury in a Korean Multicenter Retrospective Study.

BACKGROUND: Thoracic endovascular aneurysm repair (TEVAR) has been used as a primary treatment for blunt traumatic aortic injury (TAI). However, the outcomes of midterm surveillance of Seal® stent-graft durability for TAI have not been extensively studied. Thus, we aimed to report the midterm outcomes of TEVAR using the Seal® stent graft for blunt TAI. METHODS: Patients with blunt TAI treated with TEVAR using the Seal® thoracic stent graft between 2007 and 2013 in Korea were included. Midterm outcomes included technical/clinical success, in-hospital death, aorta/procedure/device-related adverse events, secondary procedures, and 30-day and all-cause mortality. RESULTS: A total of 99 patients (54% men; mean age, 48 years) were included. Grade III or higher injuries were present in 95% of patients, including 15 free ruptures of the thoracic aorta, and 64% of injuries were located in zone III. The median procedure and hospitalization duration were 90 min and 11 days, respectively. The technical success rate was 98%. The number of in-hospital mortalities (n = 8) and stroke (n = 2) were observed at 30 days. Late stroke and paraplegia (>30 days) were not observed during the mean 49 ± 26 months of follow-up (median, 48 months; range, 0-117 months). There were no aorta-related mortalities or conversions to open repair. Secondary procedures were performed in 8 patients, all of which were carotid-subclavian bypasses for delayed left subclavian occlusion. The all-cause mortality rate was 5% at 30 days and 8% at 1 year. The survival rate was 95% at 30 days, 92% at 1 year, 92% at 3 years, and 89% at 5 years. One type Ia endoleak occurred at 18 months after the procedure. CONCLUSIONS: TEVAR with the Seal® stent graft for TAI showed favorable midterm outcomes. The incidence of major adverse events after the procedure was low.

Interventional management of central vein occlusion in patients with peripherally inserted central catheter placement.

OBJECTIVE: This study evaluated the incidence of central vein occlusion (CVO) and analyzed the interventional management for CVO during peripherally inserted central catheter (PICC) placement to suggest an adequate management protocol to ensure the success and patency of PICCs. METHODS: We retrospectively reviewed the records of 2568 PICCs to identify CVO in two medical centers between January 2016 and June 2017. Procedural images were reviewed for the following items: date and indication for the PICC; type of catheter; accessed vein and arm; characteristics of CVO on ascending arm venography; PICC placement technique; indwelling period of the PICC; and follow-up records. A guidewire passage trial was performed to the CVO, as follows: a trial with a 0.018-inch single or double guidewire through the pretrimmed PICC lumen; and a trial with a combination of a 0.035-inch guidewire and a curved 5F diagnostic catheter through the PICC introducer sheath. RESULTS: The incidence of CVO was 3.2% (71/2232), and 59 patients were analyzed (23 men; mean age, 69 ± 11 years; median age, 80 years; age range, 31-92 years). Forty-four patients had thrombotic CVO, and 12 patients had acute thrombotic CVO. Thirty-six patients had occlusion of the left innominate vein, and six patients had contiguous involvement of the adjacent central vein. Forty-two patients had obtuse stump morphology of CVO, and 28 patients had grade >III collateral development. The PICC indwelling time was statistically different between the group with successful catheter advancement (n = 36, success group) and the group with failed catheter advancement (n = 18, failure group; P = .007) with ipsilateral trimmed PICCs. Eight patients had a symptomatic catheter associated with upper extremity deep venous thrombosis (UEDVT; <30 days), one in the success group and seven in the failure group. The incidence of catheter-associated UEDVT after primary PICC placement on each arm was statistically different between the success and failure groups (P = .004). CONCLUSIONS: A PICC passage trial for ipsilateral CVO is challenging but frequently successful with a simple guidewire technique, which can preserve catheter patency, decrease contralateral arm access, and prevent the development of new catheter-associated UEDVT.

The blind pushing technique for peripherally inserted central catheter placement through brachial vein puncture.

OBJECTIVE: The objective of this study was to conduct a prospective clinical trial evaluating the technical feasibility and short-term clinical outcome of the blind pushing technique for placement of pretrimmed peripherally inserted central catheters (PICCs) through brachial vein access. METHODS: Patients requiring PICC placement at any of the three participating institutions were prospectively enrolled between January and December 2016. The review boards of all participating institutions approved this study, and informed consent was obtained from all patients. PICC placement was performed using the blind pushing technique and primary brachial vein access. The following data were collected from unified case report forms: access vein, obstacles during PICC advancement, procedure time, and postprocedural complications. RESULTS: During the 12-month study period, 1380 PICCs were placed in 1043 patients. Of these, 1092 PICCs placed in 837 patients were enrolled, with 834 PICCs (76%) and 258 PICCs (34%) placed through brachial vein and nonbrachial vein access, respectively. In both arms, obstacles were most commonly noted in the subclavian veins (n = 220) and axillary veins (n = 94). Successful puncture of the access vein was achieved at first try in 1028 PICCs (94%). The technical success rate was 99%, with 1055 PICCs (97%) placed within 120 seconds of procedure time and 1088 PICCs (99%) having the tip located at the ideal position. Follow-up Doppler ultrasound detected catheter-associated upper extremity deep venous thrombosis (UEDVT) for 18 PICCs in 16 patients and late symptomatic UEDVT for 16 PICCs in 16 patients (3.1%). Catheter-associated UEDVT was noted for 28 PICCs (82%) and 6 PICCs (18%) placed through brachial vein and nonbrachial vein access, respectively. The incidence of obstacles and the procedure time (<120 seconds) differed significantly between brachial vein and nonbrachial vein access (P = .001). There was no statistically significant difference between brachial vein and nonbrachial vein access in the incidence of UEDVT (odds ratio, 0.68; 95% confidence interval, 0.59-3.52; P = .22). CONCLUSIONS: The placement of pretrimmed PICCs by the blind pushing technique and primary brachial vein access is technically feasible and may represent an alternative to the conventional PICC placement technique, having low incidences of UEDVT and other complications, with no significant difference in outcomes between brachial vein and nonbrachial vein access.

Intra-Appendiceal Air at CT: Is It a Useful or a Confusing Sign for the Diagnosis of Acute Appendicitis?

OBJECTIVE: To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis. MATERIALS AND METHODS: We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis. RESULTS: Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p < 0.001). The amount of appendiceal air was significantly lesser in patients having appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p < 0.05). Areas under the ROC curves were not significantly different between strategies 1 and 2 in reader 1 (0.971 vs. 0.985, respectively; p = 0.056), but showed a small difference in reader 2 (0.969 vs. 0.986, respectively; p = 0.042). CONCLUSION: Although significant differences were seen in the prevalence, amount, and appearance of intra-appendiceal air between patients with and without appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis.

An unusual case of vulvar schwannoma.

Schwannoma is a benign, solitary, slow-growing neoplasm of the peripheral nerve sheath. These tumors are rarely found in the external genital system, and only a few cases of vulvar schwannoma have been reported. Herein, we report a case of a vulvar schwannoma. A 37-year-old woman presented with a 3-cm-sized painless mass of the vulva which had been present for 3 years. Magnetic resonance imaging (MRI) of the pelvis showed an isolated finding of a 4.6-cm-sized round mass with a well-defined margin in the midline vulvar area. Simple excision of the tumor was undertaken, and histological examination with immunohistochemical testing demonstrated a vulvar schwannoma. Although benign schwannoma only rarely occurs in the vulva and other external areas of female genitalias, we suggest that it should be considered a differential diagnosis for patients that present a vulvar enlargement or mass. Simple surgical resection and follow-up is the most convenient treatment.

A case of a patient with Takayasu arteritis treated with left subclavian artery stent implantation.

Takayasu arteritis is an uncommon chronic inflammatory arteritis affecting large vessels, predominantly the aorta and its main branches. This disease, primarily known to be frequent in Asia and Latin America region, occurs mainly in young people between the ages of 15 and 25 years, with a male to female ratio of 1:9. Here, we report a young Asian female patient with Takayasu arteritis affecting multiple arteries and treated with percutaneous transluminal angioplasty. .

Chemoembolization for hepatocellular carcinoma supplied by a lumbar artery.

PURPOSE: To describe the radiologic findings and imaging response of hepatocellular carcinoma (HCC) supplied by the lumbar artery. METHODS: Between April 2004 and December 2012, we encountered HCC supplied by a lumbar artery in 21 patients. Two investigators retrospectively reviewed clinical and radiological findings of HCC supplied by the lumbar artery using computed tomography (CT) scans and digital subtraction angiograms. RESULTS: Patients had received 1-27 sessions of previous chemoembolization procedures (mean 7.7 sessions, median 4 sessions). Mean tumor size was 5.3 cm. The locations of HCC supplied by lumbar artery were the bare area (n = 14, 67 %) and segment VI (n = 7, 33 %). Tumor-feeding arteries arose from the main lumbar artery (n = 7), proximal anterior division (n = 4), and distal anterior division (n = 14). In 20 patients, selective chemoembolization through the tumor-feeding arteries of the lumbar artery was achieved. In 1 patient, nonselective embolization at the main lumbar artery was performed. There was no complication such as skin necrosis or paralysis. On the first follow-up enhanced CT scan, target tumors fed by the lumbar artery showed complete response (n = 6), partial response (n = 4), stable disease (n = 3), and progressive disease (n = 8), but overall tumor response was partial response (n = 1) and progressive disease (n = 20). CONCLUSION: When HCC is located in the inferior tip or bare area of the liver, a lumbar artery may supply the tumor. Although selective chemoembolization via the tumor-feeding vessel of the lumbar artery can be achieved in most cases, overall tumor response is commonly unfavorable.

Disconnection of the rubber tip of arrow-trerotola percutaneous thrombolytic device.

A rubber tip disconnection of Arrow-Trerotola percutaneous thrombolytic device (PTD) may occur occasionally. We experienced 5 cases of a rubber tip disconnection among 453 mechanical thrombectomy sessions with the use of PTD. We present a report about these five cases and suggest possible causes for the occurrences.

Morphologic classification of congenital short pancreas on multidetector computed tomography.

OBJECTIVE: The objective of this study was to assess the imaging characteristics and classify congenital short pancreas on the basis of morphologic features on multidetector computed tomography (MDCT) and to determine the associated diseases and congenital anomalies of each type. METHODS: We conducted a retrospective search from 2006 to 2012 using the keywords "short pancreas," "agenesis or hypoplasia of the dorsal pancreas," or "hypoplasia of the ventral pancreas." Clinical data and images were analyzed; finally, 24 patients with congenital short pancreas were included in this study. Imaging features of the 3 types of congenital short pancreas and their associated anomalies on MDCT were evaluated. RESULTS: Congenital short pancreas was classified into type 1 (agenesis or hypoplasia of the dorsal pancreas): no congenital anomaly but presence of diabetes mellitus (45%); type 2 (agenesis or hypoplasia of the pancreatic uncinate process): intestinal malrotation (100%); and type 3 (combined hypoplasia or agenesis of the uncinate process and dorsal pancreas): a spectrum of various congenital anomalies, including abdominal heterotaxy and abnormal spleen (100%). CONCLUSIONS: Recognizing the spectrum of agenesis or hypoplasia of the pancreas and morphologic classification of congenital short pancreas on MDCT may help radiologists detect and understand disease associated with congenital short pancreas.

Chemoembolization for hepatocellular carcinoma supplied exclusively by the hepatic falciform artery.

PURPOSE: The purpose of this study was to describe imaging appearances of hepatocellular carcinoma (HCC) supplied exclusively by the hepatic falciform artery (HFA) and safety of chemoembolization via the HFA. METHODS: During the past 6 years, we have performed chemoembolization for the treatment of 12 patients with HCCs supplied exclusively by the HFA. Computed tomography (CT) scans, digital subtraction angiograms, and medical records were retrospectively reviewed by consensus. RESULTS: Tumors were located in Couinaud segments IV (n = 7) and III (n = 5) and in subcapsular areas around the falciform ligaments. Tumor size ranged from 1.0 to 1.8 cm (mean, 1.3 cm; median, 1.3 cm). HFAs originated from A4 (n = 7), A3 (n = 4), and the left hepatic artery near the umbilical point (n = 1). All tumors were supplied exclusively by the HFA. Prophylactic embolization of the distal HFA before chemoembolization was performed using gelatin sponge particles in only one patient, and selective chemoembolization via the HFA was achieved in all patients. One patient suffered from a skin rash after chemoembolization and recovered after conservative management. Individual responses of tumors supplied exclusively by the HFA were complete response (n = 8), partial response (n = 1), and stable disease (n = 2) at the first follow-up enhanced CT scan. CONCLUSIONS: The HFA can supply HCC located in subcapsular areas around the falciform ligament, and the tumors can be safely chemoembolized without significant complications.

Enterobiliary fistula as a complication of eosinophilic gastroenteritis: a case report.

Eosinophilic gasteroenteritis is an uncommon disease with variable clinical features characterized by eosinophilic infiltration. Clinical manifestations range from non-specific gastrointestinal complaints such as nausea, vomiting, crampy abdominal pain, and diarrhea to specific findings such as malabsorption, protein loosing enteropathy, luminal obstruction, eosinophilic ascites and effusion. We report here on a case of eosinophilic gastroenteritis causing enterobiliary fistula which is an extremely unusual complication.