Monitoring of fatigue in radiologists during prolonged image interpretation using fNIRS.

PURPOSE: To determine whether functional near-infrared spectroscopy (fNIRS) allows monitoring fatigue in radiologists during prolonged image interpretation. MATERIALS AND METHODS: Nine radiologists participated as subjects in the present study and continuously interpreted medical images and generated reports for cases for more than 4 h under real clinical work conditions. We measured changes in oxygenated hemoglobin concentrations [oxy-Hb] in the prefrontal cortex using 16-channel fNIRS (OEG16ME, Spectratech) every hour during the Stroop task to evaluate fatigue of radiologists and recorded fatigue scale (FS) as a behavior data. RESULTS: Two subjects showed a subjective feeling of fatigue and an apparent decrease in brain activity after 4 h, so the experiment was completed in 4 h. The remaining seven subjects continued the experiment up to 5 h. FS decreased with time, and a significant reduction was observed between before and the end of image interpretation. Seven out of nine subjects showed a minimum [oxy-Hb] change at the end of prolonged image interpretation. The mean change of [oxy-Hb] at the end of all nine subjects was significantly less than the maximum during image interpretation. CONCLUSION: fNIRS using the change of [oxy-Hb] may be useful for monitoring fatigue in radiologists during image interpretation.

Acute traumatic superficial femoral arterial laceration findings on computed tomographic angiography: A case report.

We present a case of superficial femoral artery laceration that was identified on computed tomographic angiography. The patient was a 25-year-old man who injured his right proximal thigh while using a wood sanding machine and was transferred to our emergency department in a state of hemorrhagic shock. Following resuscitation, preoperative computed tomographic angiography helped predict the arterial injury and aided us in prompt diagnosis and decisive management.

Stent-graft treatment for extrahepatic portal vein hemorrhage after pancreaticoduodenectomy.

We report a case of intraperitoneal hemorrhage from the extrahepatic portal vein after pancreaticoduodenectomy for distal bile duct carcinoma. A stent-graft was deployed from the superior mesenteric vein to the main portal vein using a transhepatic approach. After the procedure, the patient remained free of intraperitoneal hemorrhage and was discharged 2 months later.

Percutaneous transhepatic portal vein stenting for malignant portal vein stenosis secondary to recurrent perihilar biliary cancer.

BACKGROUND: Transhepatic portal vein (PV) stenting has been shown to be one of the most important treatments for patients with PV stenosis caused by hepatopancreatobiliary malignancy. METHODS: Ten consecutive patients with PV stenosis caused by the recurrence of a perihilar biliary malignancy underwent transhepatic PV stenting. A self-expandable metallic stent was deployed at the stenosis site. The patients were retrospectively analyzed with regard to the procedure, complications, and survival after the stent placement. RESULTS: The median interval between the primary resection and the PV stenting was 22 months. The initial hepatic resection was a left trisectionectomy with caudate lobectomy in seven patients, a left hepatectomy with caudate lobectomy in one patient, a right anterior sectionectomy with caudate lobectomy following a left hepatectomy in one patient and a partial liver resection in one patient. The angle of the PV around the stenosis was greater in the patients with PV stenosis located in the right posterior PV. Eight patients with successful PV stent placement were able to receive anticancer treatment, with a median survival of 14 months. The remaining two patients without successful PV stent placement survived less than 6 months. CONCLUSIONS: Portal vein stenting might offer relief from the symptoms associated with PV hypertension and the opportunity for sustainable anticancer therapy in patients with recurrent perihilar biliary malignancy.

Assessment of percutaneous transhepatic portal vein embolization with portal vein stenting for perihilar cholangiocarcinoma with severe portal vein stenosis.

BACKGROUND: The aim of the present study was to assess the clinical efficiency of portal vein (PV) stenting when performed with preoperative percutaneous transhepatic portal vein embolization (PTPVE) in patients with severe PV stenosis due to tumor invasion. METHODS: Between 2007 and 2013, four consecutive patients (one male, three females; mean age, 52 years; age range, 25-73 years) with perihilar cholangiocarcinoma and PV stenosis underwent PTPVE and PV stenting. Patients were analyzed with regard to the procedure, hypertrophy of the future remnant liver (FRL), and plasma clearance rate of indocyanine green by the FRL (ICGK-F). Further, the %FRL volume increase in PTPVE was compared between the stenting group and the usual PTPVE group who have perihilar cholangiocarcinomas without PV stenosis. RESULTS: Preoperative PTPVE with PV stenting was successfully performed and portal flow to the FRL improved after stenting in all four patients. The %FRL volume increase was 18-60% (mean, 34%) in the stenting group and was 12-51% (mean, 21%) in the usual PTPVE group. The ICGK-F value after PTPVE exceeded 0.05 in all four patients. All patients achieved R0 resection. CONCLUSIONS: Preoperative PTPVE with PV stenting appears to be feasible in cases of severe PV tumor invasion and stenosis. This procedure may allow a broader indication for surgery.

Comparison of the central adrenal vein and the common trunk of the left adrenal vein for adrenal venous sampling.

PURPOSE: To compare left adrenal venous sampling (AVS) in two locations: the central adrenal vein and the common trunk. MATERIALS AND METHODS: A total of 22 patients (12 men and 10 women; mean age, 50 y; range, 26-65 y) who were suspected of having primary aldosteronism (PA) and underwent successful AVS with cortisol concentration measurement and/or venography between November 2010 and August 2011 were retrospectively analyzed. In regard to the left adrenal vein, collections were done at two locations: at the common trunk below the confluence of the inferior phrenic vein and at the central adrenal vein, which was above the confluence. The effects of the inflow from the inferior phrenic vein on plasma aldosterone and cortisol levels were analyzed. RESULTS: Eight patients had bilateral hypersecreting lesions and 13 had a unilateral lesion. One was diagnosed as having secondary hypertension other than PA. The median cortisol levels below and above the confluence were 129 µg/dL (range, 21-400 µg/dL) and 215 µg/dL (range, 21-690 µg/dL), respectively. The median aldosterone levels were 2,120 pg/mL (range, 164-42,700 pg/mL) and 4,275 pg/mL (range, 119-59,000 pg/mL), respectively. The median aldosterone/cortisol (A/C) ratios were 244 (range, 34-2,401) and 278 (range, 25-2,251), respectively. Cortisol and aldosterone levels were significantly higher above the confluence (P = .0050 and P = .0003, respectively), whereas the A/C ratio showed no significant difference (P = .12). CONCLUSIONS: Although higher levels of cortisol and aldosterone were obtained upstream, A/C ratio was not significantly different between the central adrenal vein and the common trunk.

Autoimmune pancreatitis: assessment of the enhanced duct sign on multiphase contrast-enhanced computed tomography.

PURPOSE: To assess the usefulness of the computed tomography (CT) finding of main pancreatic duct (MPD) wall enhancement, termed the "enhanced duct sign", for diagnosis of autoimmune pancreatitis (AIP) in comparison with diagnosis of pancreatic carcinoma and chronic pancreatitis. MATERIALS AND METHODS: Two radiologists independently evaluated the presence or absence of the enhanced duct sign on multiphase contrast-enhanced CT in patients with AIP (n=55), pancreatic carcinoma (n=50), and chronic pancreatitis (n=50). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of AIP were calculated. In patients demonstrating the enhanced duct sign, additional findings were evaluated by consensus. RESULTS: The enhanced duct sign was more frequently observed in patients with AIP (37/55, 67%) than in patients with pancreatic carcinoma (5/50, 10%) or chronic pancreatitis (0/50, 0%) (P<0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the finding were 0.67, 0.95, 0.85, 0.88, and 0.84, respectively. In AIP, the lumen within the enhanced duct was completely or partially invisible in 29 of 37 (78%) patients, and the enhanced duct was observed within the affected pancreatic parenchyma in 35 of 37 (95%) patients. In pancreatic carcinoma, the lumen within the enhanced duct was visible in all patients (5/5, 100%), and the enhanced duct was observed downstream of the tumor (5/5, 100%). CONCLUSION: The enhanced duct sign is highly specific of AIP.

Stenosis of the third portion of the duodenum due to bleeding from the anterior pancreaticoduodenal artery: assessment by multiphase contrast-enhanced examination with multislice CT.

BACKGROUND: This study was undertaken to analyze the CT findings for the rare pathological process that stenosis of the third portion of the duodenum was presumed to be caused by bleeding from the anterior pancreaticoduodenal artery. METHODS: Four consecutive patients presenting with frequent vomiting, who did not have well-known underlying disorders causing duodenal stenosis, were retrospectively recruited. Multiphase contrast-enhanced CT examinations were performed with 0.5- or 1-mm collimation. Two radiologists evaluated 2-mm axial and multiplanar reformatted images. RESULTS: In all patients, endoscopy demonstrated severe edematous stenosis of the third portion of the duodenum not associated with ulcer, bleeding, or neoplasm. The following CT findings were observed in all patients: homogenous swelling of the third portion of the duodenum associated with luminal stenosis in un-enhanced images, a band-like area of lower contrast-enhancement surrounding the walls of the third portion of the duodenum in pancreatic-phase images, and stenosis of the celiac axis. In three patients, aneurysms of the anterior pancreaticoduodenal artery in arterial-phase images were depicted. In the remaining patient, the diameter of the artery was irregular. CONCLUSIONS: Multiphase contrast-enhanced CT examination using a multislice CT scanner helps to establish the diagnosis of this pathological process.

Stent-graft treatment for bleeding superior mesenteric artery pseudoaneurysm after pancreaticoduodenectomy.

We report two cases of intraperitoneal bleeding from superior mesenteric artery (SMA) pseudoaneurysm after pancreaticoduodenectomy for pancreatic head carcinoma. In both cases, a stent-graft was deployed on the main SMA to exclude pseudoaneurysm and to preserve blood flow to the bowel. Bleeding stopped after the procedure. One patient was able to be discharged but died from carcinoma recurrence 4 months later. The other patient died of sepsis and stent-graft infection 5 months later. These patients remained free of intraperitoneal rebleeding during the follow-up period.

Arteriovenous malformation of the pancreas: assessment of clinical and multislice CT features.

BACKGROUND: This study was undertaken to analyze the clinical and CT features of arteriovenous malformation (AVM) of the pancreas. METHODS: Seven lesions in six consecutive patients (one woman and five men, mean age 51 years) with AVM of the pancreas who underwent multiphase contrast-enhanced CT with 0.5 or 1-mm collimation were retrospectively studied. CT images were evaluated and correlated with angiographic findings by two radiologists. RESULTS: In four patients, the lesions were incidental findings. Two patients presented with abdominal pain and gastrointestinal bleeding, respectively. Serum amylase levels were within normal limits in all patients. The mean size of the lesions was 32.1 mm (3.0-97.3 mm). Conglomeration of strong nodular stains and early enhancement of the portal venous system were observed for all the lesions. The diagnosis of AVM of the pancreas was retrospectively established for all lesions, but was prospectively established for four lesions. The feeding arteries of all lesions were depicted, showing agreement with those observed by angiography performed for four lesions. One lesion showed pseudocyst formation, haziness around the lesion, and strong enhancement of the duodenal wall. CONCLUSION: Multiphase CT examination using multislice CT is useful for diagnosis of AVM of the pancreas, including identification of the feeding arteries.

Endovascular management of ruptured pancreaticoduodenal artery aneurysms associated with celiac axis stenosis.

The purpose of this study was to assess the efficacy of transcatheter arterial embolization for ruptured pancreaticoduodenal artery (PDA) aneurysms associated with celiac axis stenosis (CS). Seven patients (four men and three women; mean age, 64; range, 43-84) were treated with transcatheter arterial embolization between 2002 and 2007. They were analyzed with regard to the clinical presentation, radiological finding, procedure, and outcome. All patients presented with sudden epigastric pain or abdominal discomfort. Contrast-enhanced CT showed a small aneurysm and retroperitoneal hematoma around the pancreatic head in all patients. The aneurysms ranged from 0.3 to 0.9 cm in size. In one patient, two aneurysms were detected. The aneurysms were located in the pancreaticoduodenal artery (n = 5) and the dorsal pancreatic artery (n = 3). Embolization was performed with microcoils in all aneurysms (n = 8). N-Butyl 2-cyanoacrylate (n = 1) and gelatine particle (n = 1) were also used. Complete occlusion was achieved in four patients. In the other three patients, a significantly reduced flow to the aneurysm remained at final angiography. However, these aneurysms were thrombosed on follow-up CT within 2 weeks. And there was no recurrence of the symptoms and bleeding during follow-up (mean, 28 months; range, 5-65 months) in all patients. In conclusion, transcatheter arterial embolization for PDA aneurysms associated with CS is effective. Significant reduction of the flow to the aneurysm at final angiography may be predictive of future thrombosis.

Application of subsecond rotation scan to helical CT for lung cancer screening.

PURPOSE: To clarify whether the benefit of a reduced effective scan width obtained using a smaller pitch outweighs the disadvantage of increased noise in the application of a subsecond helical CT to mass screenings for lung cancer. MATERIALS AND METHODS: Twenty-two helical CT scans of the lung were obtained in 11 healthy subjects using the following parameters: 1) scan 1 was performed at 120 kVp, 50 mA, 10-mm collimation, 1-second/rotation, helical pitch of 2.0; and 2) scan 2 was performed at 120 kVp, 50 mA, 10-mm collimation, 0.75-second/rotation, helical pitch of 1.5. Computer-generated nodules measuring 10 mm and 6 mm in diameter showing ground-glass opacity were superimposed on these images. The detectability of each nodule was evaluated by six blinded readers using ROC analysis. RESULTS: Detectability of the 6-mm nodules was significantly higher in scan 2 than in scan 1. Detectability of the 10-mm nodules was not significantly different between scans 1 and 2. CONCLUSION: The use of a smaller pitch by employing a subsecond rotation scan in a helical CT for lung cancer screenings improves the detection of small lesions without increasing either the scanning time or radiation dose.

[Chemoradiation using 5-fluorouracil (5-FU) and nedaplatin (NDP) for gynecological malignancy--the relation between hemotoxicity and sequence of 5-FU and NDP].

We compared sequence-dependent schedules of 5-fluorouracil (5-FU) and nedaplatin (NDP) for hemotoxicity in genecological malignancy (GM). The safety of schedules using 5-FU before/after NDP combined radiotherapy in 8 patients with GM was evaluated. They received either 5-FU 700 mg/m2 i.v. continuous infusion on days (D) 1-4 + NDP 100 mg/m2 i.v. bolus on D1 (group A: 5 pts), or NDP on D4, 5-FU on D1-4 (group B: pts). In group A, 4 patients received a reduced dose of NDP because of less than 60 ml/min of creatinine clearance. In group A, WBC (2 pts), hemoglobin (3 pts), and platelet (1 pts) were grade 3 or higher. In group B, grade 3 or higher in hemotoxicity was not seen. A higher percentage of hemotoxicity was seen in group A compared with group B.

Lung: feasibility of a method for changing tube current during low-dose helical CT.

A method for changing the tube current during helical scanning was applied to low-dose computed tomography (CT) in the lung. The changing method resulted in significant equalization of image noise in various lung sections compared with that at scanning with constant tube current. Detectability of nodules was equivalent between 60 mA and the changing method, whereas degradation occurred at 20 mA. This method seems feasible for the low-dose CT of lung cancer screening.

CRT diagnosis of pulmonary disease: influence of monitor brightness and room illuminance on observer performance.

Using a 21-in. cathode ray tube (CRT) monitor (2048 x 2560 x 8bits), six radiologists interpreted 12 images with interstitial lung disease under six conditions of CRT luminance (50 and 400 cd/m(2)) and room illuminance (20, 120 and 480lx), and 10 radiologists interpreted 25 images with pulmonary nodules under nine conditions of CRT luminance (50, 200 and 500 cd/m(2)) and room illuminance (20, 120 and 480lx). Observer's performance for interstitial disease was relatively better at 120lx. Four hundred and eighty lux illuminance with 50 cd/m(2) CRT luminance, which degraded the detectability of pulmonary nodule significantly (p<0.05), should be avoided for clinical use.