Yuichi Yoshie

Histopathological findings after ultraselective transcatheter arterial chemoembolization for hepatocellular carcinoma

Aim:  To evaluate the histopathologic findings in the surgical specimen of hepatocelluar carcinoma after transcatheter arterial chemoembolization (TACE) at the most distal portion of the sub‐subsegmental artery of the liver (ultraselective TACE).

Chemoembolization for the Treatment of Large Hepatocellular Carcinoma

PURPOSE To retrospectively evaluate the efficacy of chemoembolization for inoperable hepatocellular carcinoma (HCC) tumors larger than 5 cm in diameter. MATERIALS AND METHODS Chemoembolization was performed in 30 patients with HCCs with a largest diameter of more than 5 cm with three or fewer lesions and no portal vein tumor thrombus. The mean maximum tumor diameter was 7.7 cm +/- 2.4. When the tumor was extremely large and had multiple feeding arteries, stepwise chemoembolization sessions at intervals of 3-10 weeks were performed. In addition, extrahepatic collateral supply was identified and embolized. Local therapeutic effects, survival rates, and complications were analyzed. RESULTS The mean follow-up period was 33.8 months +/- 24.1. One to 13 chemoembolization sessions (mean, 4.0 sessions +/- 3.0) were performed in each patient. Additionally, 62 collateral vessels were embolized in 21 patients, including 22 vessels in 14 patients at the initial procedure. Early tumor response rate 2-3 months after treatment was 43.3% by Response Evaluation Criteria In Solid Tumors. Complete radiologic response was achieved in 19 patients. Eleven patients died between 4 and 61 months after treatment (mean, 27.2 months +/- 21.8), including four deaths unrelated to hepatic causes. Nineteen patients have survived for 6-103 months (mean, 37.5 months +/- 25.2). Overall and progression free-survival rates at 1, 3, and 6 years were 82.3% and 66.0%, 73.9% and 57.6%, and 32.9% and 34.2%, respectively. Three infectious complications developed and were managed by interventions. CONCLUSIONS Chemoembolization was effective for large HCCs, although there is a risk of infectious complications after the procedure.

Hepatocellular carcinoma in the caudate lobe of the liver: variations of its feeding branches on arteriography

There are usually multiple caudate arteries arising from the right, left, and middle hepatic arteries, and they are frequently connected to each other. Therefore, hepatocellular carcinoma (HCC) in the caudate lobe is frequently fed by multiple branches arising from different origins. HCC located in the Spiegel lobe is usually fed by the caudate arteries derived from the right and/or left hepatic artery. HCC in the paracaval portion is mainly fed by the caudate artery derived from the right hepatic artery; with low frequency, it is fed by the caudate artery derived from the left hepatic artery. HCC in the caudate process is usually fed by the caudate artery derived from the right hepatic artery. Because of the complexity and overlap of vascular territories, the tumor-feeding branch of a recurrent HCC lesion in the caudate lobe frequently changes on follow-up arteriograms. In addition, several extrahepatic collateral vessels supply the recurrent tumor. To perform effective transcatheter arterial chemoembolization (TACE) for HCC in the caudate lobe, radiologists should have sufficient knowledge of vascular anatomy supplying HCC in the caudate lobe.

Inferior phrenic arteries: angiographic anatomy, variations, and catheterization techniques for transcatheter arterial chemoembolization

The inferior phrenic artery (IPA) is the most common extrahepatic collateral vessel to hepatocellular carcinoma (HCC); however, there are many anatomical variations in its origin and branches. In addition, the IPA is frequently reconstructed through several pathways, mainly through the retroperitoneal network, because of the occlusion of its orifice due to atherosclerosis or previous catheter manipulation. Infrequently, selective catheterization into the IPA is impossible even using a microcatheter, particularly in the IPA that originates from the proximal or distal portion of the celiac trunk or from the aorta with an acute angle. In this article, we describe anatomical variations of the IPA and catheterization techniques, such as a catheter with a large side hole and a catheter with a cleft, to facilitate catheterization into the IPA that is difficult using a conventional coaxial technique. Radiologists should have sufficient knowledge of such variations and catheterization techniques to perform transcatheter arterial chemoembolization for HCCs through the IPA effectively and safely.

MR Spectroscopy to Distinguish between Supratentorial Intraventricular Subependymoma and Central Neurocytoma

Purpose: The purpose of this study was to discriminate supratentorial intraventricular subependymoma (SIS) from central neurocytoma (CNC) using magnetic resonance spectroscopy (MRS). Methods: Single-voxel proton MRS using a 1.5T or 3T MR scanner from five SISs, five CNCs, and normal controls were evaluated. They were examined using a point-resolved spectroscopy. Automatically calculated ratios comparing choline (Cho), N-acetylaspartate (NAA), myoinositol (MI), and/or glycine (Gly) to creatine (Cr) were determined. Evaluation of Cr to unsuppressed water (USW) was also performed. Mann-Whitney U test was carried out to test the significance of differences in the metabolite ratios. Detectability of lactate (Lac) and alanine (Ala) was evaluated. Results: Although a statistically significant difference (P < 0.0001) was observed in Cho/Cr among SIS, control spectra, and CNC, no statistical difference was noted between SIS and control spectra (P = 0.11). Statistically significant differences were observed in NAA/Cr between SIS and CNC (P = 0.04) or control spectra (P < 0.0001). A statistically significant difference was observed in MI and/or Gly to Cr between SIS and control spectra (P = 0.03), and CNC and control spectra (P < 0.0006). There were no statistical differences between SIS and CNC for MI and/or Gly to Cr (P = 0.32). Significant statistical differences were found between SIS and control spectra (P < 0.0053), control spectra and CNC (P < 0.0016), and SIS and CNC (P < 0.0083) for Cr to USW. Lac inverted doublets were confirmed in two SISs. Triplets of Lac and Ala were detected in four spectra of CNC. Conclusion: The present study showed that MRS can be useful in discriminating SIS from CNC.

Splenial and White Matter Lesions Showing Transiently-reduced Diffusion in Mild Encephalopathy Monitored with MR Spectroscopy and Imaging

We report the time course of magnetic resonance imaging and spectroscopy of a case with lesions of the splenium and white matter with transiently reduced diffusion in clinically reversible encephalopathy. Initially normal spectroscopy showed slightly elevated choline. Signal abnormality in T2-weighted and fluid-attenuated inversion recovery images persisted for 90 days. Lesions of the splenium and white matter with transiently reduced diffusion in clinically reversible encephalopathy are not always reversible and may reflect heightened glial cell-membrane turnover without neuronal damage.

Technical success rates and long-term patency of endovascular treatment for occluded native hemodialysis fistulas: comparison between thrombotic occlusion and nonthrombotic occlusion

PurposeThis study evaluated the technical success and long-term patency of endovascular treatment for occluded native hemodialysis fistulas caused by thrombotic occlusion (TO) and nonthrombotic occlusion (NTO).Materials and methodsThis cohort included 96 consecutive occlusions (70 TOs and 26 NTOs) at the forearm. Clinical success and patency rates of endovascular treatment were calculated and compared between the TO and NTO groups.ResultsOverall clinical success rate was 91.6%; and primary, assisted primary, and secondary patency rates at 1, 2, and 3 years were 49.6%, 30.7%, and 28.3%, respectively; 73.8%, 48.3%, and 48.3%, respectively; and 80.7%, 72.3%, and 66.2%, respectively. Clinical success rates of the TO and NTO groups were 91.4% and 92.3%, respectively. The 1-, 2-, and 3-year primary, assisted primary, and secondary patency rates of the TO group were 54.4%, 29.3%, and 25.6%, respectively; 70.7%, 49.4%, and 49.4%, respectively, and 78%, 68.8%, and 64,2%, respectively. Those of the NTO group were 38.9%, 32.4%, and 32.4%, respectively; 81.2%, 47.3%, and 40.6%, respectively; and 87%, 80.3%, and 70.2%, respectively. There were no significant differences between the clinical success and patency rates of the two groups.ConclusionOccluded native hemodialysis fistulas were restored with high frequency, without significant differences between clinical success and patency in the TO and NTO groups.

Long-term predictive factors of the morphology based outcome in bare platinum coiled intracranial aneurysms: Evaluation by pre- and post-contrast 3D time-of-flight MR angiography

PURPOSE Our aim was to identify long-term predictive factors of the morphology-based outcome (MBO) of bare platinum coiled intracranial aneurysms. MATERIALS AND METHODS A retrospective analysis of 96 bare platinum coiled intracranial aneurysms followed up from 1997 to 2016 using pre- and post-contrast 3D time-of-flight MR angiography (MRA) was performed. Logistic regression analysis was used to identify factors associated with a positive history of surrounding coil mass enhancement (SCME) and poor MBO. Spearmans rank correlation test was used to analyze the relationship between the initial angiographic result (IAR) class, sequential change of the SCME category, and MBO grade. RESULTS Factors independently associated with poor MBO were incomplete IAR (OR=14.94, 95%CI: 2.46, 289.21, P=0.002) and a history of SCME (OR=4.13, 95% CI: 1.05, 18.65, P=0.043). The MBO grade strongly correlated with the IAR class (correlation coefficient [r]=0.84, P<0.0001). MBO grade correlated with sequential change of the SCME category (r=0.56, P<0.0001). The sequential change of the SCME category correlated with IAR class (r=0.53, P<0.0001). CONCLUSION Although IAR and its class were strong long-term predictive factors of MBO, a history of SCME and upgrading of sequential change of SCME category were also long-term predictive factors of the MBO of bare platinum coiled intracranial aneurysms.

Cranial Pachymeningeal Involvement in POEMS Syndrome: Evaluation by Pre- and Post-contrast FLAIR and T1-weighted Imaging

Purpose: To evaluate the cranial pachymeningeal involvement of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) syndrome using pre- and post-contrast fluid-attenuated inversion recovery (FLAIR) and T1-weighted imaging (T1WI). Methods: The appearance of pachymeningeal involvement in nine cases of POEMS syndrome was evaluated using pre- and post-contrast FLAIR and T1WI. The degree of pachymeningeal thickening was graded as normal or abnormal using pre-contrast FLAIR. The degrees of contrast enhancement effect were evaluated based on pre- and post-contrast images, and recorded in each of three separate anatomical areas, i.e., the falx cerebri, cerebral convexity, and tentorium cerebelli. The degrees of contrast enhancement of pachymeninges were graded as not detected (ND), positive, or prominent on post-contrast FLAIR, and normal range (NR), positive, and prominent on post-contrast T1WI. Results: Pre-contrast FLAIR demonstrated 41% of pachymeningeal anatomical regions as areas of thickening. Post-contrast FLAIR did not detect any contrast enhancement on 26% of the regions but showed positive enhancement on 30% and prominent enhancement on 44%. Post-contrast T1WI showed normal range enhancement on 48%, positive enhancement on 11%, and prominent enhancement on 41% of the regions. Post-contrast FLAIR showed the highest percentage for detection of pachymeningeal abnormalities (74%). Conclusion: Post-contrast FLAIR may contribute to objective judgment in the evaluation of pachymeningeal involvement in POEMS syndrome.

Striatal hemihypoplasia: An early embryonic variant of cerebral hemiatrophy

We present a case of hemihypoplasia of the striatum with ipsilateral cerebral hemispheric atrophy. The head of the caudate nucleus and putamen were hypoplastic, and gray matter cell bridges between them located in the anterior limb of the internal capsule were sparse. Cerebral atrophy was accompanied by ipsilateral mesial temporal sclerosis without thalamic atrophy. The anterior limb of the internal capsule showed no signal abnormalities or volume loss. These imaging findings and the hyperintensity at the fundus striati suggest an early embryonic insult of lateral striatal elevation.