[The Ascending Pharyngeal Artery, Accessory Meningeal Artery, Lingual Artery, Vasa Nervorum, and Potential Anastomotic Channels].

The ascending pharyngeal, accessory meningeal, and lingual arteries branch from the proximal segment of the external carotid artery. These branches give rise to smaller branches that contribute blood supply to the pharyngeal mucosa, parapharyngeal tissue, middle ear, submandibular tissues, tongue, and dura mater of the middle and posterior fossa. These arteries may also supply the cranial nerves and have potential anastomotic channels that function with the internal carotid and vertebral arteries. M igration of embolic material into the vasa nervorum and potential anastomoses may cause complications. Therefore, knowledge of these functional anatomies is crucial for neuro-interventionalists.

Effectiveness of 18F-FDG PET/CT in finding lung metastasis from a retroperitoneal paraganglioma.

A 50-year-old woman was diagnosed with iron deficiency anemia on general medical examination. Further, contrast-enhanced abdominal CT and magnetic resonance imaging revealed a large hypervascular mass with internal degeneration and necrosis in the retroperitoneal space. She was referred to our hospital for further evaluation and treatment. Because the paraganglioma was most likely as the imaging diagnosis, 123I-MIBG scintigraphy was performed. It revealed the marked abnormal accumulation in the retroperitoneal lesion indicating the paraganglioma and no other abnormal accumulation was noted. Several plasma catecholamines and their urinary metabolites were normal. On the subsequent 18F-FDG PET/CT, high FDG uptake was found in the retroperitoneal lesion (SUVmax=38). FDG uptake was also found in a small nodule at the base of the lower lobe of the right lung (SUVmax= 9.8). Contrast-enhanced imaging revealed a hypervascular nodule at the base of the right lung, suggesting pulmonary metastasis of a paraganglioma. The abdominal lesion and right lung nodule were excised, and retroperitoneal paraganglioma and pulmonary metastasis were diagnosed based on the pathology findings. In this case, 18F-FDG PET/CT was useful in the search for paraganglioma metastasis. We report a relationship between 123I-MIBG accumulation and 18F-FDG uptake in paraganglioma and review the relevant literature.

Characteristic findings of primary perirenal angiosarcoma on chemical shift subtraction magnetic resonance imaging (CSS-MRI): A case report.

A 70-year-old man with supraglottic carcinoma underwent computed tomography (CT) for staging purposes. A tumor measuring approximately 7 × 10 cm was found incidentally in the left perirenal space. The tumor showed homogeneous high signal intensity on chemical shift subtraction magnetic resonance imaging (CSS-MRI) suggesting the presence of minimal amounts of fat. Five months later, the tumor had grown to approximately 10 × 12 cm with indistinct margins. CSS-MRI showed high signal intensity in the tumor periphery only. The tumor was resected and the pathological diagnosis was angiosarcoma. Angiosarcomas are malignant endothelial vascular neoplasms that are highly invasive to their surroundings. Here we report a case of primary perirenal angiosarcoma that was difficult to differentiate from a dedifferentiated liposarcoma. On CSS-MRI, high signal intensity within a tumor may be a characteristic feature of primary perirenal angiosarcoma.

Corrigendum to "Characteristic findings of primary perirenal angiosarcoma on chemical shift subtraction magnetic resonance imaging (CSS-MRI): A case report" [Radiology Case Reports 19 (2023) 285-289].

[This corrects the article DOI: 10.1016/j.radcr.2023.10.037.].

Utility of non-contrast-enhanced magnetic resonance imaging in predicting preoperative clinical stage and prognosis in patients with thymic epithelial tumor.

PURPOSE: The purpose of this study was to find useful imaging features on non-contrast-enhanced magnetic resonance imaging (MRI) that can divide patients with thymic epithelial tumor (TET) into clinical stage I-II and III-IV groups under assumption that contrast media are contraindicated. MATERIALS AND METHODS: This retrospective study included 106 patients (median age, 60 years; range, 27-82 years; 62 women) with surgically resected TET who underwent MRI between August 1986 and July 2015. All cases were classified according to the 2015 WHO classification and staged using the eighth edition of the TNM system. Two radiologists independently evaluated 14 categories of MRI findings; the findings in patients with stage I-II were compared with those of patients with stage III-IV using a logistic regression model. Disease-specific survival associated with significant findings was calculated using the Kaplan-Meier method. RESULTS: Univariate analysis showed that stage III-IV patients were more likely to have tumors with an irregular contour, heterogeneity on T1WI, low-signal intensity on T2WI, irregular border with lung, findings of great vessel invasion (GVI) (hereafter, GVI sign), pericardial thickening/nodule, and lymphadenopathy (all, P < 0.01). On multivariable analysis, only two findings, irregular border between tumor and lung (odds ratio [OR], 272.8; 95% CI 26.6-2794.1; P < 0.001) and positive GVI sign (OR, 49.3; 95% CI 4.5-539.8; P = 0.001) remained statistically significant. Patients with one or both features had significantly worse survival (log-rank test, P < 0.001). CONCLUSION: For patients with TET who are unable to receive contrast for preoperative staging, the two image findings of an irregular border between tumor and lung and the positive GVI sign on non-contrast-enhanced MRI could be helpful in determining stage III-IV disease which is associated with a worse survival.

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated bronchioloalveolar disorder required differentiation from fibrotic chronic hypersensitivity pneumonitis.

We encountered a case of HTLV-1-associated bronchioloalveolar disorder (HABA) that was difficult to distinguish from fibrotic chronic hypersensitivity pneumonitis (CHP). Chest thin-section computed tomography (CT) showed diffuse micronodules and revealed peribronchovascular and perilobular distribution. Further, thickening of the interlobular septa, areas of ground-glass attenuation, traction bronchiectasis/bronchiolectasis, and air trapping were observed. Based on these findings, diseases that cause lymphatic tract abnormalities and fibrotic CHP were considered differential diseases. A surgical lung biopsy was performed, and an HTLV-1 antibody was detected using the Western blot analysis of bronchoalveolar lavage fluid. The final diagnosis of HABA was made through a multidisciplinary discussion.

Arterial Administration of DNA Crosslinking Agents with Restraint of Homologous Recombination Repair by Intravenous Low-Dose Gemcitabine Is Effective for Locally Advanced Pancreatic Cancer.

(1) Background: Pretreatment by Rad51-inhibitory substances such as gemcitabine followed by arterial chemotherapy using antineoplastic agents causing DNA crosslink might be more beneficial for patients with locally advanced pancreatic cancers than conventional treatments. The efficacy of arterial administration of DNA crosslinking agents with pretreatment of intravenous low-dose gemcitabine for patients with unresectable locally advanced or metastatic pancreatic cancer (LAPC or MPC) is evaluated. (2) Methods: A single-arm, single-center, institutional review board-approved prospective study was conducted between 2005 and 2015. Forty-five patients (23 LAPC, 22 MPC) were included. Patients received a weekly low dose of gemcitabine intravenously for three weeks followed by arterial administration of mitomycin C and epirubicin hydrochloride at tumor-supplying arteries on the fifth or sixth week. This treatment course was repeated at 1.5-to-2-month intervals. Overall survival (OS), local progression-free survival (LPFS), and therapeutic response were evaluated. LAPC or MPC were divided according to treatment compliance, excellent or poor (1 or 2), to subgroups L1, L2, M1, and M2. (3) Results: OS of LAPC and MPC were 23 months and 13 months, respectively. The OS of LAPC with excellent treatment compliance (subgroup L1, 10 patients) was 33 months with 31 months of LPFS, and four patients (40%) had a complete response (CR). The OS of the L1 subgroup was significantly longer than those of other subgroups L2, M1, and M2, which were 17 months, 17 months, and 8 months, respectively. As Grade 3 adverse effects, severe bone marrow suppression, interstitial pneumonitis, and hemolytic uremic syndrome were observed in six (13.0%), three (6.5%), and three (6.5%) patients, respectively. (4) Conclusions: Arterial DNA crosslinking with the systemic restraint of homologous recombination repair can be a new treatment option for LAPC.

T1 invasive lung adenocarcinoma: Thin-section CT solid score and histological periostin expression predict tumor recurrence.

Adenocarcinoma is the most common histological type of non-small cell lung cancer (NSCLC), and various biomarkers for predicting its prognosis after surgical resection have been suggested, particularly in early-stage lung adenocarcinoma. Periostin (also referred to as POSTN, PN or osteoblast-specific factor) is an extracellular matrix protein, the expression of which is associated with tumor invasiveness in patients with NSCLC. In the present study, the novel approach, in which the thin-section CT findings prior to surgical resection and periostin expression of resected specimens were analyzed in combination, was undertaken to assess whether the findings could be a biomarker for predicting the outcomes following resection of T1 invasive lung adenocarcinoma. A total of 73 patients who underwent surgical resection between January 2000 and December 2009 were enrolled. A total of seven parameters were assessed in the thin-section CT scans: i) Contour; ii) part-solid ground-glass nodule or solid nodule; iii) percentage of solid component (the CT solid score); iv) presence of air-bronchogram and/or bubble-like lucencies; v) number of involved vessels; vi) shape linear strands between the nodule and the visceral pleura; and vii) number of linear strands between the nodule and the visceral pleura. Two chest radiologists independently assessed the parameters. Periostin expression was evaluated on the basis of the strength and extent of staining. Univariate and multivariate analyses were subsequently performed using the Cox proportional hazards model. There was a substantial to almost perfect agreement between the two observers with regard to classification of the seven thin-section CT parameters (κ=0.64-0.85). In the univariate analysis, a CT solid score >80%, pathological lymphatic invasion, tumor and lymph node status and high periostin expression were significantly associated with recurrence (all P<0.05). Multivariate analysis demonstrated that a CT solid score >80% and high periostin expression were risk factors for recurrence (P=0.002 and P=0.011, respectively). The cumulative recurrence rates among the three groups (both negative, CT solid score >80% or high periostin expression, or both positive) were significantly different (log-rank test, P<0.001). Although the solid component is already known to be a major predictor of outcome in lung adenocarcinomas according to previous studies, the combined analysis of CT solid score and periostin expression might predict the likelihood of tumor recurrence more precisely.

Intracranial solitary fibrous tumor/hemangiopericytoma mimicking cystic meningioma: A case report and literature review.

Intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a relatively rare type of tumor that originates from meningeal mesenchyme. A 30-year-old man presented leaning his body to the left and with weakness of his left lower limb. Computed tomography revealed a heterogeneous mass with multiple cystic components and hyperostosis of the right cranial convexity. Magnetic resonance imaging showed the mass was broadly attached to the dura matter with dural tail sign. In addition, the lesion had extensive cystic degeneration and a solid compartment showing low apparent diffusion coefficient values. The patient underwent gross total resection of the intracranial lesion and presented no recurrence within a 12-month follow-up period. Histopathology confirmed SFT/HPC (World Health Organization grade Ⅱ). Although there have been several useful techniques reported to differentiate SFT/HPC from meningioma, in this case the atypical findings for SFT/HPC made it difficult. We report the imaging findings of this case and some literature reviews.

Venous Anatomy of the Cavernous Sinus and Relevant Veins.

The cavernous sinus (CS) is a dural sinus located on each side of the pituitary fossa. Neoplastic and vascular lesions, such as arteriovenous fistulas, frequently involve the CS. This sinus plays a role as a crossroad receiving venous blood flow from the facial, orbital, meningeal, and neural venous tributaries. The relationship between these surrounding relevant veins and the CS, as well as the CS itself, varies anatomically. For safe and effective surgical and endovascular treatment of lesions involving the CS, knowledge of the anatomy and variations of the CS and the relevant surrounding veins is highly important. In this section, the anatomy and variations of the CS and the relevant surrounding veins are outlined.

Leakage sign for acute subdural hematoma in clinical treatment.

BACKGROUND: Acute subdural hematoma (ASDH) is a serious traumatic disease, and predictive methods for hematoma growth are necessary to decide whether emergent operation is necessary. This study aimed to evaluate the incidence of "leakage" using computed tomography angiography (CTA) in patients with ASDH and to identify its prognostic value. METHODS: Sixty-seven patients with ASDH were examined using CTA (mean age 64.1 ± 20.6 years; 24 men) by analyzing two serial scans (CTA phase and delayed phase). We defined a positive leakage sign as a > 10% increase in Hounsfield units (HU) in the region of interest. Hematoma expansion was determined using plain CT after 24 h in patients who did not undergo emergent surgery. RESULTS: Of the 67 patients, conservative therapy was administered to 35 patients; of these patients, 9 showed hematoma expansion, and 8 of these 9 patients (88.9%) showed positive leakage signs. The sensitivity and specificity of leakage signs to hematoma expansion in the no-surgery group were 88.8% and 76.1%, respectively. All positive leakage signs were found within 4.5 h of injury; patients showing negative leakage signs showed a decreased tendency towards hematoma 24 h after injury. Patients presenting with positive leakage signs had poor outcomes. CONCLUSIONS: The results indicated that the leakage sign is a sensitive predictor of hematoma expansion and poor outcomes in ASDH. If the hematoma is small but leakage sign-positive, strict observation is necessary and aggressive surgery may improve outcomes.

Renal Arteriovenous Shunts: Clinical Features, Imaging Appearance, and Transcatheter Embolization Based on Angioarchitecture.

Renal arteriovenous (AV) shunt, a rare pathologic condition, is divided into two categories, traumatic and nontraumatic, and can cause massive hematuria, retroperitoneal hemorrhage, pain, and high-output heart failure. Although transcatheter embolization is a less-invasive and effective treatment option, it has a potential risk of complications, including renal infarction and pulmonary embolism, and a potential risk of recanalization. The successful embolization of renal AV shunt requires a complete occlusion of the shunted vessel while preventing the migration of embolic materials and preserving normal renal arterial branches, which depends on the selection of adequate techniques and embolic materials for individual cases, based on the etiology and imaging angioarchitecture of the renal AV shunts. A classification of AV malformations in the extremities and body trunk could precisely correspond with the angioarchitecture of the nontraumatic renal AV shunts. The selection of techniques and choice of adequate embolic materials such as coils, vascular plugs, and liquid materials are determined on the basis of cause (eg, traumatic vs nontraumatic), the classification, and some other aspects of the angioarchitecture of renal AV shunts, including the flow and size of the fistulas, multiplicity of the feeders, and endovascular accessibility to the target lesions. Computed tomographic angiography and selective digital subtraction angiography can provide precise information about the angioarchitecture of renal AV shunts before treatment. Color Doppler ultrasonography and time-resolved three-dimensional contrast-enhanced magnetic resonance angiography represent useful tools for screening and follow-up examinations of renal AV shunts after embolization. In this article, the classifications, imaging features, and an endovascular treatment strategy based on the angioarchitecture of renal AV shunts are described.

Balloon-Occluded Retrograde Transvenous Obliteration for Isolated Gastric Varices Draining through Pericardiophrenic Vein without Gastrorenal or Gastrocaval Shunts.

Balloon-occluded retrograde transvenous obliteration (BRTO) is an effective and minimally invasive treatment for isolated gastric varices (GVs) that is usually performed through a gastrorenal shunt (GRS) or gastrocaval shunt (GCS). However, there are some cases in which GVs drain mainly into the left pericardiophrenic vein without an accessible GRS or GCS. This brief report presents four cases of GVs without a GRS/GCS treated by BRTO through the pericardiophrenic vein. BRTO was successfully performed with the use of flexible balloon catheters without any complications in all four patients, and the GVs were completely obliterated.

Unenhanced magnetic resonance angiography with time-spatial labeling inversion pulse for evaluating visceral artery aneurysms after endosaccular packing with detachable coils: preliminary results.

The aim of this brief report is to compare unenhanced magnetic resonance (MR) angiography with time-spatial labeling inversion pulse (Time-SLIP) with conventional digital subtraction angiography (DSA) in assessing degree of saccular visceral artery aneurysm (VAA) occlusion after endosaccular packing with detachable coils. Eight patients with VAAs (five renal and three splenic artery aneurysms) were enrolled in this study. VAA occlusion rates based on Time-SLIP MR angiography were complete occlusion in four patients, neck remnants in three patients, and body filling in one patient. These findings corresponded with the DSA findings.

Anatomic features and retrograde transvenous obliteration of duodenal varices associated with mesocaval collateral pathway.

PURPOSE: To evaluate techniques and efficacy of retrograde transvenous obliteration for the treatment of duodenal varices associated with mesocaval collateral pathway. MATERIALS AND METHODS: Six consecutive cases of large/growing or ruptured duodenal varices treated by retrograde transvenous obliteration were retrospectively reviewed. Selective balloon-occluded retrograde transvenous obliteration (B-RTO) with 5% ethanolamine oleate (EO) was performed in all cases. When EO could not be sufficiently stagnated in the varices, additional/alternative techniques were performed, including coil embolization of afferent vein or intravariceal injection of n-butyl-2-cyanoacrylate (NBCA). Clinical findings, anatomic features of duodenal varices, obliteration techniques, complications, posttherapeutic computed tomography (CT) findings, and follow-up endoscopic findings were investigated. RESULTS: All duodenal varices were located at the second/third junction of the duodenum and were fed by single (n = 1) or multiple (n = 5) pancreaticoduodenal veins. One varix fed by a single afferent vein was successfully treated by simple selective B-RTO technique alone. The other five cases required coil embolization of afferent vein (n = 1) or intravariceal injection of NBCA (n = 4) because sclerosant was not sufficiently stagnated in the varices. CT 1 week after the procedure showed complete occlusion of the varices in all cases. A duodenal ulcer at the variceal site developed in one patient and was successfully treated by medication. Follow-up endoscopy showed disappearance of varices in all cases, and no recurrence was observed during follow-up. CONCLUSIONS: Retrograde transvenous obliteration is an effective technique for the treatment of duodenal varices. However, additional/alternative techniques are required for successful treatment because of the complex anatomic features of duodenal varices.

Partial thrombosis of gastric varices after balloon-occluded retrograde transvenous obliteration: CT findings and endoscopic correlation.

OBJECTIVE: The purpose of our study was to investigate the frequency and outcomes of partial thrombosis of gastric varices after balloon-occluded retrograde transvenous obliteration (BRTO). MATERIALS AND METHODS: We reviewed retrospectively 69 consecutive patients with gastric varices who were followed-up for > 6 months after treatment with BRTO. All patients underwent contrast-enhanced CT and gastroscopy before and after BRTO. Imaging findings of gastric varices with particular attention to afferent veins, degree of thrombosis, and variceal changes were investigated. RESULTS: On the basis of pretherapeutic CT images, gastric varices were classified into two types: simple (< 3 afferent veins) and complex (≥ 3 afferent veins). Initial follow-up CT showed complete thrombosis in 58 patients (84%) and partial thrombosis in 11 (16%). Partial thrombosis was observed more frequently in complex-type varices (25% vs 9%). No regrowth or recurrent varices were observed in completely thrombosed varices. Follow-up endoscopy showed regrowth of gastric varices at 6-24 months after BRTO in five patients; all of these were complex-type and partially thrombosed varices. All five recurrent varices were treated successfully with repeated BRTO. CONCLUSION: Partial thrombosis after BRTO can occur in complex-type gastric varices, which have a higher risk of regrowth. Additional techniques that achieve complete thrombosis are required for long-term efficacy for complex-type gastric varices.

Fibrous stroma and vascularity of pancreatic carcinoma: correlation with enhancement patterns on CT.

OBJECTIVE: To demonstrate the contrast-enhancement behavior of pancreatic carcinoma on dynamic contrast-enhanced CT (DCE-CT), and the relationship between the degree of contrast-enhancement and the vascularity (vessel density) and amount of fibrous stroma (fibrosis within the tumor) on pathological specimen. METHODS: The contrast-enhancement values were measured by producing the subtracting images for obtaining largest region of interests to reduce measurement errors and variability. Vascularity was determined by immunostaining of the tissue sections with factor 8 and the fibrous stroma was determined by picrosirius staining. Correlation of the findings of DCE-CT with pathological findings was performed in 21 patients with pancreatic carcinoma. RESULTS: All but one patient exhibited a gradually increasing enhancement, but there was considerably wide range in contrast-enhancement values of tumors. Examination of the overall relationship between vascularity and fibrous stroma with contrast-enhancement behavior showed that tumor with more fibrosis and higher vascularity had a higher contrast effect through all phases of dynamic study. Tumors having liver metastases tended to be less fibrotic than tumors without liver metastases. CONCLUSION: The contrast-enhancement behavior of pancreatic carcinoma may be helpful in estimating vascularity and the extent of tumor fibrosis and possibility of liver metastases.

Salivary duct carcinoma of the extra-glandular segment of Stensen's duct: radiological findings and pathological correlation (2008: 10b).

Salivary duct carcinoma (SDC) of the extra-glandular segment of Stensen's duct is a very rare but aggressive neoplasm. Ultrasonography, computed tomography, and magnetic resonance imaging findings in a patient pathologically proven to have SDC of the extra-glandular segment of Stensen's duct are reported. When an early peak enhancement region in the mass with a well-enhanced dilated and thickened Stensen's duct wall is apparent on dynamic studies, a SDC of the extra-glandular segment of Stensen's duct should be strongly suspected.

Clinical and pulmonary thin-section CT findings in acute Klebsiella pneumoniae pneumonia.

The aim of this study was to assess the clinical and pulmonary thin-section CT findings in patients with acute Klebsiella pneumoniae pneumonia. We retrospectively evaluated thin-section CT examinations performed between January 1991 and December 2007 from 962 patients with acute Klebsiella pneumoniae pneumonia. Seven hundred and sixty-four cases with concurrent infectious diseases were excluded. Thus, our study group comprised 198 patients (118 male, 80 female; age range 18-97 years, mean age 61.5). Underlying diseases and clinical findings were assessed. Parenchymal abnormalities were evaluated along with the presence of enlarged lymph nodes and pleural effusion. CT findings in patients with acute Klebsiella pneumoniae pneumonia consisted mainly of ground-glass attenuation (100%), consolidation (91.4%), and intralobular reticular opacity (85.9%), which were found in the periphery (96%) of both sides of the lungs (72.2%) and were often associated with pleural effusion (53%). The underlying conditions in patients with Klebsiella pneumoniae pneumonia were alcoholism or smoking habit.