Rescue computed tomography-guided drainage of a giant mediastinal mature teratoma causing airway obstruction prior to surgical resection: a case report.

BACKGROUND: Giant mediastinal mature teratomas may cause airway obstruction or decreased venous return due to the mass effect. Preoperative stabilization of the respiratory and circulatory systems is important for perioperative management to safely perform surgery, including general anesthesia. However, to the best of our knowledge, there are only a few reports regarding the preoperative computed tomography (CT)-guided drainage of mediastinal tumors. CASE PRESENTATION: A 30-year-old woman was admitted to the emergency room with sudden dyspnea. CT findings revealed a giant cystic mass in the anterior mediastinum compressing the trachea and the right main bronchus. The patient was intubated and CT-guided drainage of the fluid content of the cyst was performed to decompress the airway obstruction. Thereafter, the mediastinal tumor was resected during elective surgery and pathologically diagnosed as a mature teratoma. CONCLUSIONS: Rescue preoperative CT-guided drainage of a giant mediastinal mature teratoma allowed safe general anesthesia and surgery by releasing the airway obstruction.

Gastric Artery Injury Due to Blunt Abdominal Trauma.

Gastric artery injury resulting from blunt abdominal trauma is rare, with only eight previous cases documented in the published literature. Our report describes a case involving an injury to the right gastric artery with concomitant injuries to the liver and spleen, for which arterial embolization targeting the right gastric artery was performed. The patient, a 66-year-old woman without any remarkable medical history, was involved in a motor vehicle accident. She was brought to the hospital in a state of shock and complaining of upper abdominal pain. Contrast-enhanced CT indicated hepatic and splenic injuries, intra-abdominal hemorrhaging, and effusion of contrast medium, suggesting involvement of the right gastric artery. Subsequent angiography confirmed irregularities in the diameter of the right gastric artery, prompting coil embolization. A conservative therapeutic approach was selected due to the absence of evidence regarding active hemorrhage or vascular injury within the hepatic or splenic regions. The patient remained clinically stable following the embolization, without any sequelae. Arterial embolization is warranted if preoperative contrast CT indicates signs of hemorrhage, even if hemostasis is ostensibly attained during angiography. Our findings allude to the feasibility of non-operative management (NOM) rather than laparotomy for cases of gastric artery injury.

Effectiveness of Cytological Diagnosis with Outer Cannula Washing Solution for Computed Tomography-Guided Needle Biopsy.

RATIONALE AND OBJECTIVES: We evaluated the availability of cytological diagnosis with outer cannula washing solution (C-OCWS) as a clinical diagnostic tool for computed tomography (CT)-guided needle biopsy. MATERIALS AND METHODS: We retrospectively assessed 109 consecutive patients (71 males, 38 females; median age 68 years), who underwent CT-guided needle biopsy. In all patients, the specimens sampled by the inner needle were used for histological diagnosis, and those taken from the outer cannula were rinsed with 0.9% saline solution: outer cannula washing solution for cytological diagnosis. The accuracy of C-OCWS in addition to histological diagnosis were compared with that of histological diagnosis alone. We used binary logistic regression analysis to determine the variables associated with diagnostic accuracy for malignancy and lesion characteristics. RESULTS: The C-OCWS method precisely diagnosed 7 (6.4%) malignant lesions (i.e., effective cases) in the 109 patients characterized as "negative for malignancy" via histological diagnosis alone. The accuracy of the combination of C-OCWS and histological diagnoses was significantly higher than that of histological diagnosis alone (0.95 vs. 0.89, respectively; p = 0.023). Multivariate logistic regression analysis showed that increasing only a marginal ratio (failure rate for proper position of biopsy needle within the tumor) was independently associated with a high rate of effective cases (p = 0.003). CONCLUSION: C-OCWS may be helpful for improving the quality of CT-guided needle biopsy, and is a simple method that may not necessarily increase the patients' physical burden.

High-signal venous sinuses on MR angiography: discrimination between reversal of venous flow and arteriovenous shunting using arterial spin labeling.

PURPOSE: It is sometimes difficult to differentiate between high signals originating from a reverse flow on magnetic resonance angiography (MRA) and occult arteriovenous shunting. We attempted to determine whether arterial spin labeling (ASL) can be used to discriminate reversal of venous flow from arteriovenous shunting for high-signal venous sinuses on MR angiography. METHODS: Two radiologists evaluated the signals of the venous sinus on MRA and ASL obtained from 364 cases without arteriovenous shunting. In addition, the findings on MRA were compared with those on ASL in an additional 13 patients who had dural arteriovenous fistula (DAVF). RESULTS: In the 364 cases (728 sides) without arteriovenous shunting, a high signal due to reverse flow in the cavernous sinuses (CS) was observed on 99 sides (13.6%) on MRA and none on ASL. Of these cases, a high signal in the sigmoid sinus, transverse sinus, and internal jugular vein was seen on 3, 3, and 8 sides, respectively. All of these venous sinuses showed a high signal from the reverse flow on MRA images. CONCLUSION: ASL is a simple and useful MR imaging sequence for differentiating between reversal of venous flow and CS DAVF. In the sigmoid and transverse sinus, ASL showed false-positives due to the reverse flow from the jugular vein, which may be a limitation of which radiologists should be aware.

Treatment strategy for a penetrating stab wound to the vertebral artery: a case report.

CASE: Vertebral artery injury is a low-frequency but high-mortality injury. The surgical approach to a bleeding vertebral artery injury is one of the most difficult procedures in trauma surgery.A 64-year-old woman was transported to our emergency department after being stabbed in the middle side of the right neck with a large kitchen knife. Her initial hospital examination indicated a shock state, and computed tomography images revealed a right vertebral artery injury. We undertook angiography and transcatheter arterial embolization before the surgical operation. OUTCOME: The patient suffered right upper extremity paralysis due to brachial plexus injury and was transferred to another hospital for rehabilitation on the 24th hospital day. CONCLUSION: Computed tomography angiography for diagnosis and interventional radiology treatment are useful for the management of penetrating neck trauma. Transcatheter arterial embolization for vertebral artery injury is safe and allows for easy control of bleeding compared to a surgical procedure.

Simple Endovascular Repair for Symptomatic Aberrant Right Subclavian Artery in a Debilitated Patient.

We report a simple endovascular repair for symptomatic aberrant right subclavian artery (ARSA) in an 11-year-old girl. She had undergone tracheostomy due to hypoxic encephalopathy after cardiac surgery and suffered from dyspnea. Computed tomography revealed tracheal stenosis caused by a vascular ring made with an ARSA and the right common carotid artery. Transcatheter ARSA embolization using an Amplatzer vascular plug and coils was performed. Symptoms improved within a few days after this intervention and no complications such as upper extremity ischemia were encountered. Computed tomography showed the ARSA around the trachea had reduced in size and tracheal stenosis was improved.

Interventional Treatment for Giant Hepatic Hemangioma Accompanied by Arterio-portal Shunt with Ascites.

A 73-year-old woman with massive ascites associated with a giant hepatic mass accompanied by arterio-portal (AP) shunt was admitted to our hospital. Based on contrast-enhanced computed tomography (CT) and angiography findings, hepatic hemangioma with AP shunt and ascites due to portal hypertension was diagnosed. Transcatheter arterial embolization (TAE) by N-butyl-2-cyanoacrylate (NBCA) was performed without complications. The patient's ascites disappeared, and her liver function test results improved after the treatment. The patient has maintained a steady state for two years. This case indicates that TAE with NBCA is a safe and effective treatment for hepatic hemangioma accompanied by AP shunt.

Impact of pretreatment whole-tumor perfusion computed tomography and 18F-fluorodeoxyglucose positron emission tomography/computed tomography measurements on local control of non-small cell lung cancer treated with stereotactic body radiotherapy.

This study aimed to investigate the correlation between the average iodine density (AID) detected by dual-energy computed tomography (DE-CT) and the maximum standardized uptake value (SUVmax) yielded by [18F] fluorodeoxyglucose positron emission tomography (18F-FDG PET) for non-small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT). Seventy-four patients with medically inoperable NSCLC who underwent both DE-CT and 18F-FDG PET/CT before SBRT (50‒60 Gy in 5‒6 fractions) were followed up after a median interval of 24.5 months. Kaplan-Meier analysis was used to determine associations between local control (LC) and variables, including AID, SUVmax, tumor size, histology, and prescribed dose. The median AID and SUVmax were 18.64 (range, 1.18-45.31) (100 µg/cm3) and 3.2 (range, 0.7-17.6), respectively. No correlation was observed between AID and SUVmax Two-year LC rates were 96.2% vs 75.0% (P = 0.039) and 72.0% vs 96.2% (P = 0.002) for patients classified according to high vs low AID or SUVmax, respectively. Two-year LC rates for patients with adenocarcinoma vs squamous cell carcinoma vs unknown cancer were 96.4% vs 67.1% vs 92.9% (P = 0.008), respectively. Multivariate analysis identified SUVmax as a significant predictor of LC. The 2-year LC rate was only 48.5% in the subgroup of lower AID and higher SUVmax vs >90% (range, 94.4-100%) in other subgroups (P = 0.000). Despite the short follow-up period, a reduction in AID and subsequent increase in SUVmax correlated significantly with local failure in SBRT-treated NSCLC patients. Further studies involving larger populations and longer follow-up periods are needed to confirm these results.

Temporal variations in stump pressure and assessment of images obtained from cone-beam computed tomography during balloon-occluded transarterial chemoembolization.

AIM: Balloon-occluded transcatheter arterial chemoembolization (B-TACE) was used to show the optimized duration of balloon occlusion to start injection of lipiodol in order to maximize lipiodol deposition in the nodule, and to reveal the endpoint of lipiodol injection. METHODS: Of 29 consecutive patients who underwent balloon-occluded TACE between November 2013 and February 2014, we were able to measure stump pressure for 219 nodules in 27 patients. Tumors were counted, measured and could be visually assessed in 20 of these patients at 26 sites. Tumors with multiple feeders were found in eight patients. Arterial blood pressure was measured before, immediately after and 5 min after balloon occlusion prior to intra-arterial injection, as well as before and after balloon deflation after intra-arterial injection. Images were assessed qualitatively by two radiologists as well as quantitatively by calculating the contrast-to-noise ratio. RESULTS: We found no significant difference in pressure between immediately after and 5 min after balloon occlusion. Mean stump pressure before balloon deflation after intra-arterial injection was 70.4 mmHg. We observed a significant increase in qualitative scores after balloon occlusion (P < 0.001), and the mean score in the third-order branch was significantly higher than that in the first-order branch (P = 0.048). CONCLUSION: Our results indicate that intra-arterial injection can be started at any time after balloon occlusion and that 70 mmHg may be considered as a possible indicator of the end-point for arterial injection.

Contribution of dynamic sentinel lymphoscintigraphy images to the diagnosis of patients with malignant skin neoplasms in the upper and lower extremities.

The aim of the present study was to confirm the contribution of dynamic images in sentinel lymphoscintigraphy in malignant skin neoplasms: precisely, to investigate if dynamic images were necessary and to observe if dynamic images could reduce the areas needed for biopsy and dissection. Twenty-five patients with malignant skin neoplasms of the lower (n = 21) and upper (n = 4) extremities were retrospectively investigated. Images were evaluated by two independent reviewers, an expert in diagnostic radiology and nuclear medicine and a diagnostic radiologist in training. Visualized hot spots were assessed to be sentinel nodes using only static planar images. Next, both static planar and dynamic images were assessed. Reviewers scored diagnostic confidence values of determined sentinel nodes as follows: 0, cannot be decided; 1, possible; 2, probable; and 3, definitive. Patterns of lymphatic drainage were categorized into six different pathways: (1) inguinal type, (2) popliteal type, (3) inguinal and popliteal type, (4) axillary type, (5) cubital type, and (6) axillary and cubital type. In cases in the lower extremities, with dynamic images, the expert reviewer changed assessment in three cases and the trainee reviewer changed it in one case. There were no cases in which a decision was changed to be the same between both reviewers. Although the average diagnostic confidence value of assessment is usually higher with dynamic images, significant differences were not present. In cases of the upper extremities, both reviewers changed their assessment in one patient. By mutual agreement, cases in which assessment was changed with dynamic images were the inguinal and popliteal type, and the axillary and cubital type. The expert reviewer noticed lymphatic channels only visualized on dynamic images and changed assessment. Determination of whether or not a lymph node is a sentinel node depends on visualization of the lymphatic network. In the present circumstances, all biopsies of hot spots determined to be lymph nodes should not be excluded. However, excessive biopsies should be avoided as much as possible. It is necessary to use dynamic images alongside skillful observation.

Subarachnoid hemorrhage in a patient with a meningioma and an unruptured aneurysm.

Subarachnoid hemorrhage (SAH) is usually elicited by cerebrovascular disease and infrequently by brain tumors. A 64-year-old woman presented with SAH with a left petrous meningioma and an unruptured left internal carotid-posterior communicating artery (IC-PcomA) aneurysm. She suffered sudden onset of headache and nausea followed by consciousness disturbance 7 days after onset. Computed tomography (CT) revealed diffuse SAH and a tumor at the petrous portion. Angiography demonstrated a left IC-PcomA aneurysm. Under a diagnosis of a ruptured aneurysm and a coincidental meningioma, we performed neck clipping of the aneurysm. However, intraoperatively we found that the aneurysm was unruptured and we subsequently performed tumor resection. Intraoperatively we could not find the cause of SAH during resection of the meningioma. The histological diagnosis was transitional meningioma with deposition of fibrin on the surface of the tumor. The findings of initial CT and magnetic resonance imaging, and pathological results could not conclude the definitive etiology of SAH in this case.

Venous cerebral infarction in a patient with peripheral hemodialysis shunt and occlusion of the left brachiocephalic vein.

Intracranial venous congestion is a rare condition in hemodialysis patients with central venous occlusion. We report a patient with cerebral venous infarction resulting from high reflex flow into the cranium induced by an arteriovenous hemodialysis shunt in the arm and occlusion of the brachiocephalic vein. This case illustrates that abnormal extracranial venous circulation should be considered when cerebral venous congestion is assumed to produce neurologic symptoms in patients with an arteriovenous shunt.

Lymphoscintigraphy for sentinel lymph node mapping in Japanese patients with malignant skin neoplasms of the lower extremities: comparison with previously investigated Japanese lymphatic anatomy.

OBJECTIVES: Lymph nodes (LN) and lymphatic drainage were identified by lymphoscintigraphy using 99(m)Tc-phytate in order to map the sentinel lymph nodes (SLNs) in patients with malignant skin neoplasms of the lower extremities, and to compare the results with an atlas of Japanese lymphatic anatomy. METHODS: Sentinel lymphoscintigraphs of 18 patients with malignant skin neoplasms of the lower extremities (9 men, 9 women; age range 45-84 years, mean age 66 years) were analyzed retrospectively, and the LNs detected were identified as SLNs or secondary nodes. RESULTS: The patterns of lymphatic drainage were divided into three different categories: (1) initial drainage into inguinal LN without visualization of popliteal LNs (inguinal type), (2) initial drainage into popliteal LNs and then into intrapelvic LNs (popliteal type), and (3) initial drainage into both popliteal and inguinal LNs (inguinal and popliteal type). More than half of the cases were the inguinal and popliteal type, as both inguinal and popliteal LNs were identified as SLNs. In the cases in which the hallux and its surrounding area were injected, all were the inguinal type and popliteal LNs were not visualized. In one case, only dynamic images detected lymphatic drainage without visualization of popliteal LNs. In contrast to the previously published literature on Japanese lymphatic anatomy, SLN lymphatic drainage from the skin of the lower extremities was wide and overlapping in many areas. However, in agreement with currently accepted anatomy, only the great saphenous lymphatic vessel drained the skin of the hallux and its surrounding area. The present results suggest that it is important to confirm lymphatic drainage in order to identify SLNs in the lower extremities. CONCLUSIONS: The patterns of lymphatic drainage from the skin of the foot were divided into three different categories. In contrast to previously published Japanese lymphatic anatomy, lymphatic drainage from the skin of the lower extremities was wide and overlapping in many areas. However, only the great saphenous lymphatic vessel drained the skin of the hallux and its surrounding area in agreement with currently accepted Japanese lymphatic anatomy. It is important to confirm lymphatic drainage to identify SLNs in the lower extremities.

Dilated outer diameter of the dissected artery: acute bilateral anterior cerebral artery dissection evaluated by repeat magnetic resonance cisternography. Case report.

A 42-year-old male patient presented with an anterior cerebral artery (ACA) dissection manifesting as sudden onset of severe headache. Initial computed tomography revealed faint subarachnoid hemorrhage in the frontal region. Initial angiography showed tapering stenosis at the A(2) segment of right ACA. The patient was admitted to our hospital and treated conservatively. Magnetic resonance (MR) imaging and angiography did not detect intramural hematoma, intimal flap, or double lumen at the stenotic right A(2) segment. The ACA dissection was difficult to confirm based on the findings on day 0. ACA dissection was confirmed by improvement of the right ACA stenosis on follow-up angiography on day 14. On the other hand, MR cisternography revealed a fusiform dilatation of the vascular outer contour at the right A(2) on day 0, which had resolved on day 14. Cerebral angiography and MR cisternography similarly suggested asymptomatic contralateral (left) A(2) dissection on day 14. Fusiform dilatation of the vascular outer contour at the affected segment on MR cisternography may be indicative of arterial dissection in the acute phase.

Incidence of unilateral distal vertebral artery aplasia: evaluation by combining basiparallel anatomic scanning-magnetic resonance imaging (BPAS-MRI) and magnetic resonance angiography.

PURPOSE: The incidence of a unilateral aplastic distal vertebral artery (VA) has been reported as 0.2% of cases on cerebral angiography. During our daily magnetic resonance (MR) examinations, however, we frequently encounter MR angiograms (MRAs) that do not demonstrate unilateral VA. The purpose of this study was to calculate the frequency of aplastic unilateral distal VA by MR images performed for asymptomatic people. MATERIALS AND METHODS: Over a time span of 1 year, 237 asymptomatic people (140 men, 97 women; ages 28-67 years, mean 54.4 years) underwent brain MRI during a "brain check-up examination" in our hospital. To identify an aplastic unilateral distal VA, we retrospectively compared three-dimensional time-of-flight MRA with basiparallel anatomic scanning (BPAS)-MRI which was designed for recognition of the arterial outer contour. RESULTS: Aplasia of the unilateral distal VA was confirmed in 11 persons (4.6%). According to our classification, hypoplastic distal VA in 12 (5.1%) and asymptomatic acquired unilateral distal VA occlusion was also proved in 2 (0.8%). CONCLUSION: We found that the frequency of aplastic unilateral VA was 4.6% in asymptomatic people using a combination of MRA and BPAS-MRI for assessment of an intracranial VA.

Bolus injection of contrast agents with various iodine concentrations and delivery rates for intracranial three-dimensional CT angiography: evaluation of intracranial arteriovenous contrast using a multidetector-row CT scanner.

PURPOSE: We evaluated the difference in computed tomography (CT) attenuation values of the intracranial arterial and venous systems among the various contrast injection protocols (higher iodine delivery rate or higher concentration of the agent) on the source images of intracranial three-dimensional CT angiography (3D-CTA) using a multidetector-row CT (MDCT) scanner. MATERIALS AND METHODS: We used 100 ml of iopamidol 300 at an injection rate of 3.0 ml/s, 100 ml of iopamidol 300 at an injection rate of 3.7 ml/s, and 80 ml of iopamidol 370 at an injection rate of 3.0 ml/s. There were 10 patients in each group. Attenuation values of the bilateral internal carotid arteries (ICAs), basilar artery trunk, bilateral cavernous sinuses (CSs), and Galenic vein were measured quantitatively on the axial CT angiographic source images obtained by four-channel MDCT. RESULTS: Injection of the high-concentration contrast with a higher iodine-delivery rate achieved good arteriovenous contrast at the cavernous portion. With the same rate of iodine delivery, injection of the intermediate concentrate agent increased the CT value of not only the ICAs but also the CSs. CONCLUSION: High-concentration contrast could increase ICA attenuation without intracavernous attenuation gain during the "first-pass" phase.