Kenji Ibukuro

Air Embolism and Needle Track Implantation Complicating CT-Guided Percutaneous Thoracic Biopsy: Single-Institution Experience

OBJECTIVE The objective of our study was to present the details and incidence of air embolism and needle track implantation in patients who underwent percutaneous CT-guided thoracic biopsy. MATERIALS AND METHODS We retrospectively reviewed 1,400 percutaneous CT-guided thoracic biopsies during the period from August 1993 to August 2008. A case with air embolism was considered to be a patient with hypotension during or after biopsy and with an air embolism confirmed on CT. A needle track implantation was considered to be a mass in the needle track on the postbiopsy follow-up CT. RESULTS There were three (0.21%) cases of air embolism. Air embolisms were confirmed in the left ventricle, coronary artery, ascending aorta, and pulmonary vein. The pulmonary venous wall was pathologically identified in one case. Although there were no fatalities, two patients needed resuscitation. Left hemiplegia occurred in one case, but it gradually disappeared. There were four (0.56%) cases of needle track implantation in 713 pathologically proven malignant thoracic biopsy cases with follow-up CT scans. Two were primary lung cancer and the others were lung metastasis (renal cell carcinoma and osteosarcoma). Implantation was found 4-7 months (mean, 5.6 months) after the biopsy, and size was 2.5-5.6 cm (mean, 3.5 cm). CONCLUSION The incidence of air embolism with clinical symptoms and needle track implantation complicating percutaneous thoracic biopsy is more frequent than the previously reported rate.

The subclavius posticus muscle: a factor in arterial, venous or brachial plexus compression ?

During dissection practice in 1993 and 1995 to 1999, we found an aberrant muscle which connected the first costal cartilage and the superior margin of the scapula in 12 sides (4.8%) of 11 cadavers (8.9%) among 248 sides of 124 cadavers. The muscle originated from the cranial surface of the sternal end of the first rib, ran laterodorsally, and inserted into the superior margin of the scapula. According to the origin and insertion, the aberrant muscle was considered to be the subclavius posticus (Rosenmüller, 1800). We also examined the supraclavicular region of a living subject by MR imaging to estimate the course of such an aberrant muscle. It is thought that the aberrant muscle runs on the anterior surface of the subclavian vein and crosses over the brachial plexus. Such a muscle could be considered as a possible factor causing the Paget-von Schrötter syndrome which is recognized as spontaneous or effort-related thrombosis of the axillo-subclavian vein. It is recommended to take into account the possible existence of such an aberrant muscle during the examination of patients with thoracic outlet syndrome, especially in those with symptoms of venous compression.

Anatomical variants of the lateral femoral circumflex artery: an angiographic study

The descending branch of the lateral femoral circumflex artery (LFCA) has found recent use as a new arterial graft for coronary artery bypass grafting (CABG). Anatomical variants of the LFCA were assessed on femoral arteriograms obtained before CABG in 131 adult patients. The most common pattern, found in 78.6% of extremities, consisted of the LFCA arising from the deep femoral artery, and the arterial graft was selected from this pattern in 92.3% of patients in whom the descending branch of the LFCA was used for CABG.

Hepatic falciform ligament artery: Angiographic anatomy and clinical importance

The hepatic falciform ligament artery (HFLA) was evaluated by angiography and also by dissections. Based on the findings, the mechanism of the post-chemoembolization skin rash was studied. A total of 340 liver cirrhosis patients who underwent hepatic artery chemoembolization for hepatocellular carcinoma were reviewed in terms of the angiographic incidence of the HFLA, variations in its origin, and the incidence of skin rash. The HFLA was demonstrated in 26 (7.6%) of the 340 patients on angiography. Two HFLAs were observed in one patient. The origin was the middle hepatic artery (A4) in 16 cases, the superior branch of the middle hepatic artery in three, the inferior branch of the middle hepatic artery in two, the inferior branch of the left hepatic artery (A3) in three, and the confluence of A3 and A4 in three cases. There were no patients who developed post-chemoembolization skin rash. Two cadavers were dissected to investigate the anastomosis between the HFLA and the subcutaneous artery. Two different anastomoses were found: (1) direct and (2) via the ensiform branch of the internal thoracic artery. These were located at the lower and upper part of the falciform ligament, respectively. The distribution of a chemotherapeutic agent through these anastomoses is the likely cause of post-chemoembolization skin rash. If prophylactic embolization of the proximal portion of the HFLA using a metallic coil is performed, the skin rash will be prevented.

Balloon-occluded retrograde transvenous obliteration of gastric varix draining via the left inferior phrenic vein into the left hepatic vein.

We encountered a patient with gastric varix draining not via the usual left suprarenal vein but via the left inferior phrenic vein joining the left hepatic vein. Transfemoral balloon-occluded retrograde transvenous obliteration (BRTO) of the varix was performed under balloon occlusion of the left inferior phrenic vein via the left hepatic vein and retrograde injection of the sclerosing agent (5% of ethanolamine oleate) into the gastric varix. Disappearance of the gastric varix was confirmed on endoscopic examination 2 months later.

Vascular anatomy of the pancreas and clinical applications

SummaryThe development of recent technology, especially the helical computed tomography (CT) scan, allows us to observe small peripancreatic vessels which previously could be demonstrated only by angiography (1), and therefore make three-dimensional (3-D) volume rendered CT angiographic reconstruction possible (2). The neighboring structures as well as the pancreatic vessels are clearly visualized on the axial CT scan. Therefore, it is necessary to define the peripancreatic vessels on the axial images, as well as on angiography to make an accurate diagnosis of pancreatic disease so that we can also estimate the dynamic flow of the peripancreatic vessels.In this chapter, I would like to use the cadaver dissections of pancreatic vessels to explain each pancreatic vessel based on previous anatomic and radiologic references and finally demonstrate the clinical cases in terms of the pancreatic vessels.The pancreatic arteries and veins are explained based on the anatomic and radiologic references. Principal pancreatic vessels are demonstrated on cadaver dissection. The pancreas head is supplied by the anterior and posterior pancreaticoduodenal arteries forming arcades in the pancreaticoduodenal sulcus and is drained by the pancreaticoduodenal veins. The pancreas body and tail are supplied by the dorsal, inferior, and caudate pancreatic arteries, and are drained by the inferior and left pancreatic veins.Clinical applications in terms of the pancreatic vessels such as basis for interpretation of the angiography and the CT scan, treatment of pancreatitis and pancreatic cancer, detection of small insulinoma are stated.

The left inferior phrenic artery arising from left hepatic artery or left gastric artery: radiological and anatomical correlation in clinical cases and cadaver dissection

BackgroundThe purpose of this study is to assess angiographic and CT appearance of left inferior phrenic artery (LIPA) arising from left hepatic or left gastric artery and to recognize its specific anatomical location with the help of cadaver dissection. MethodsWe retrospectively reviewed 761 abdominal angiographies and found 13 patients (1.7%) with LIPA arising from left hepatic or left gastric artery. We classified those origins and assessed radiological features. We also presented a cadaver dissection to identify anatomical location of LIPA arising from left hepatic artery.ResultsThe origin of the LIPA was classified as follows: (a) left hepatic artery: four, (b) accessory left gastric artery: one, (c) accessory left hepatic artery: three, and (d) left gastric artery: five patients. The proximal portion was located in gastrohepatic ligament and its distal portion was located in front of esophageal hiatus. In a cadaver dissection, the proximal portion ascends along ligamentum venosum and distal portion courses along superior aspect of left hemi diaphragm in front of esophagus.ConclusionThe LIPA rarely arises from left hepatic or left gastric artery. The proximal portion was located in gastrohepatic ligament and the distal portion runs in front of the esophageal hiatus.

Protective effect against repeat adverse reactions to iodinated contrast medium: Premedication vs. changing the contrast medium.

AbstractObjectivesThe purpose of this study was to assess the protective effect of premedication and changing contrast media (CM) against repeat adverse reactions (ARs) to iodinated CM.MethodsBetween January 2006 and September 2014, 771 cases with previous ARs to CM were administered CM. The same CM that had caused ARs previously was administered to 491 cases (220 without premedication [defined as the control group], and 271 with premedication [the premedication alone group]). A different CM from the previous CM was given to 280 cases (58 without premedication [the changing CM alone group], and 222 with premedication [the premedication and changing CM group]).ResultsThe control group had 61 repeat ARs (27.7%). The premedication alone group had 47 ARs (17.3%, p<0.01). The changing CM alone group had 3 ARs (5.2%, p<0.001). Three ARs (7.9%) were observed in 38 cases changing from one to another low-osmolar nonionic CM. Twenty cases with previous ARs to the high-osmolar CM and to the low-osmolar ionic CM showed no ARs. The premedication and changing CM group had 6 ARs (2.7%, p<0.001).ConclusionPremedication prior to contrast for patients with previous ARs may be protective, however, changing CM was more effective.Key Points• In patients with previous adverse reactions, changing contrast media is recommended. • Premedication is unnecessary against previous reactions to high-osmolar or ionic CM. • Changing from one to another low-osmolar non-ionic CM may be effective.

Spatial relationship between intrahepatic artery and portal vein based on the fusion image of CT-arterial portography (CTAP) and CT-angiography (CTA): New classification for hepatic artery at hepatic hilum and the segmentation of right anterior section of the liver

PURPOSE To clarify the variations of the intrahepatic artery and portal vein and to verify the proper segmentation for the right anterior section of the liver. MATERIALS AND METHODS CT during arterial portography and CT angiography were performed on 64-slice multi detector row CT in 147 patients. All images were transferred to a workstation for analysis using multi-image-fusion mode. We investigated the spatial relationship between hepatic artery and portal vein in the right hemiliver and the segmentation of the right anterior hepatic artery and portal vein. RESULTS The spatial anatomy of right hepatic arteries and portal vein was (1) anterior and posterior hepatic artery run superior and inferior to anterior portal vein, respectively (47.6%), (2) one anterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (15%), (3) anterior and posterior hepatic arteries run superior to anterior portal vein (11.6%), (4) anterior and posterior hepatic arteries run inferior to anterior portal vein (7.5%), and (5) one posterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (6.8%). The combined anatomy of right anterior artery and portal vein with regard to segmentation was classified as (1) dorso-ventral (26.5%), (2) dorso-ventral and inferior (10.9%), (3) multiple (18.4%), and (4) superior and inferior segments (1.4%). CONCLUSION There are various types of spatial anatomy of intrahepatic artery and portal vein. The hepatic arteries as well as portal veins of right anterior section of the liver could be divided into dorsal and ventral, not superior and inferior.

The congenital anastomoses between hepatic arteries:angiographic appearance

The purpose of this study was to evaluate congenital anastomoses between hepatic arteries demonstrated on angiography in ten patients and to correlate the anastomosis with types of hepatic arterial anatomy. We evaluated the types of the hepatic arterial anatomy based on Michels’ classification for 720 patients and compared the anatomic types between the patients with the anastomoses (ten patients) and without the anastomoses (710 patients). The diameter of the anastomoses ranged from 1.5 to 3.0 mm (mean, 2.4 mm). Five anastomoses were classified as tortuous type and five as straight type. Based on Michels’ classification for types of hepatic arterial anatomy, eight (80%) of ten patients with the congenital anastomoses were classified as type III (replaced right hepatic artery from superior mesenteric artery). The remaining two patients were classified as type IV (replaced right hepatic artery from superior mesenteric artery and replaced left hepatic artery from left gastric artery) and type VIIIa (replaced right hepatic artery from superior mesenteric artery and accessory left hepatic artery from left gastric artery). Eight (16%) of 48 patients who were classified as type III have the anastomoses. In conclusion, the congenital anastomoses were observed especially in patients with replaced right hepatic artery from superior mesenteric artery.