Tsuneo Ishiguchi

Cerebrospinal Dysfunction After Endovascular Stent-Grafting via a Median Sternotomy: The Frozen Elephant Trunk Procedure

BACKGROUND Endovascular stent grafting through a median sternotomy for a distal arch aneurysm (the frozen elephant trunk procedure) is an alternative to synthetic graft replacement. But spinal cord dysfunction can easily occur as a complication after surgery. Although its cause is uncertain, some attempts at prevention have been instituted. We address the mechanism of spinal cord dysfunction and evaluate the efficacy of our preventive measures. METHODS There were 22 men and 2 women with an average age of 71 (59 to 83) years. There were 22 true aneurysms (13 fusiform, nine saccular), one chronic dissection, and one penetrating aortic ulcer. The following strategies for prevention of spinal cord dysfunction were utilized: low flow perfusion through both axillary arteries (n = 10); pigtail catheter guidance (n = 19); use of a shorter graft with anchoring sutures (n = 12); flooding of the operative field with carbon dioxide (n = 7); aortic unclamping (n = 7), and use of ultra-thin woven Dacron grafts (n = 15). RESULTS There was no operative mortality, but cerebrospinal dysfunction complicated four cases (17%): one paraplegia, one stroke along the basilar artery, and two cases of temporary spinal cord dysfunction (paresthesia of the right leg and urinary disturbance). Cerebrospinal dysfunction tended to occur in fusiform aneurysms (31%, p = 0.044). Except when low flow antegrade perfusion through both the axillary arteries was utilized, which resulted in no cases of paraplegia or paraparesis (p = 0.064), the methods used for prevention of cerebrospinal dysfunction appeared to have little efficacy. CONCLUSIONS Cerebrospinal dysfunction is a serious complication of the frozen elephant trunk procedure. Its cause has not been clarified, but it tends to occur in fusiform-type aneurysms. Antegrade perfusion through both axillary arteries while the aorta is open may be helpful in its prevention.

Role of ultrasonography in the detection of intraductal spread of breast cancer: correlation with pathologic findings, mammography and MR imaging

Abstract. The purpose of this study was to assess the role of US in the detection of intraductal spread of breast cancer in comparison with mammography (MMG) and MRI. In 46 patients with breast cancer, US features of the intraductal component were classified as ductal type or distorted type. Histopathologically, 29 of 46 (63 %) cases had intraductal components, and the sensitivity, specificity, and accuracy rates in detection of intraductal spread were 89, 76, and 85 %, respectively. Each US pattern demonstrated good correspondence to the histologic components, and the distorted type correlated well with comedo-type carcinoma. Mammography was performed in all cases, and the sensitivity, specificity, and accuracy rates in detection of intraductal spread were 55, 100, and 72 %, respectively. In comedo type, MMG could diagnose the extent of intraductal spread more accurately compared with US examination. Magnetic resonance imaging comparison was available in 25 cases. Magnetic resonance imaging depicted intraductal extension as an enhanced area during the early phase of a contrast enhancement study with a sensitivity of 93 %. Ultrasound and MRI were closely related in terms of morphologic characteristics: the ductal type of US image correlated well with linear enhancement on MRI, whereas the distorted type correlated with regional or segmental enhancement. Current US examination is useful in depicting the intraductal spread of breast cancer; however, US has a tendency to underestimate intraductal component of comedo type compared with MMG and MRI.

Budd-Chiari Syndrome with Long Segmental Inferior Vena Cava Obstruction: Treatment with Thrombolysis, Angioplasty, and Intravascular Stents

The authors describe a patient with Budd-Chiari syndrome caused by long segmental thrombotic obstruction of the inferior vena cava associated with paroxysmal nocturnal hemoglobinuria. The patient was successfully treated with a combination of local thrombolytic therapy, balloon angioplasty, and placement of Gianturco expandable metallic stents.

Fusion of MRI and Sonography Image for Breast Cancer Evaluation Using Real-time Virtual Sonography with Magnetic Navigation: First Experience

OBJECTIVE We recently developed a real-time virtual sonography (RVS) system that enables simultaneous display of both sonography and magnetic resonance imaging (MRI) cutaway images of the same site in real time. The aim of this study was to evaluate the role of RVS in the management of enhancing lesions visualized with MRI. METHODS Between June 2006 and April 2007, 65 patients underwent MRI for staging of known breast cancer at our hospital. All patients were examined using mammography, sonography, MRI and RVS before surgical resection. Results were correlated with histopathologic findings. MRI was obtained on a 1.5 T imager, with the patient in the supine position using a flexible body surface coil. Detection rate was determined for index tumors and incidental enhancing lesions (IELs), with or without RVS. RESULTS Overall sensitivity for detecting index tumors was 85% (55/65) for mammography, 91% (59/65) for sonography, 97% (63/65) for MRI and 98% (64/65) for RVS. Notably, in one instance in which the cancer was not seen on MRI, RVS detected it with the supplementation of sonography. IELs were found in 26% (17/65) of the patients. Of 23 IELs that were detected by MRI, 30% (7/23) of IELs could be identified on repeated sonography alone, but 83% (19/23) of them were identified using the RVS system (P = 0.001). The RVS system was able to correctly project enhanced MRI information onto a body surface, as we checked sonography form images. CONCLUSIONS Our results suggest that the RVS system can identify enhancing breast lesions with excellent accuracy.

Delayed rupture of a pseudoaneurysm following pancreatoduodenectomy: report of a case.

Abstract We report herein the case of a 63-year-old man in whom delayed rupture of a pseudoaneurysm occurred 120 days following pancreatoduodenectomy. Color Doppler examination indicated a pseudoaneurysm originating from the ligated gastroduodenal artery. Transcatheter arterial embolization was done at the common hepatic artery, proximal and distal to the pseudoaneurysm, with microcoils. The patient had a minor elevation of liver enzymes, which subsequently returned to normal. Due to the absence of any postoperative complications such as pancreatic anastomotic leakage, we assumed that the pseudoaneurysm formation had been caused by a weakness in the arterial wall according to skeletonization resulting from lymphadenectomy and intraoperative radiation therapy. To our knowledge, this case represents the longest interval between pancreatoduodenectomy and rupture of a pseudoaneurysm ever to be reported in the literature.

Safety of Gadoterate Meglumine (Gd-DOTA) as a Contrast Agent for Magnetic Resonance Imaging: Results of a Post-Marketing Surveillance Study in Japan

AbstractBackground: Safety is a primary concern with contrast agents used for MRI. If precautions could be taken before the repeated administration of gadolinium-based contrast media, then the awareness and management of adverse reactions would be more efficient. Objectives: To assess the safety and efficacy of gadoterate meglumine (Gd-DOTA) [Magnescope® in Japan, Dotarem® in other countries], a gadolinium-based contrast agent, in patients undergoing imaging of the brain/spinal cord and/or trunk/limbs, and to identify factors associated with the onset of adverse reactions. Methods: The study ran for 4 years and included 3444 cases. The study was conducted before it became known that gadolinium-based contrast agents could trigger the development of nephrogenic systemic fibrosis. Patients for whom the contrast agent was indicated and who underwent imaging of the brain/spinal cord and/or trunk/limbs by MRI were enrolled. There were 1300 inpatients who were followed up during hospitalization (for several days), and 2144 outpatients who were followed up for at least 2 hours on-site. After Gd-DOTA administration, 13 patient baseline characteristics were used to explore factors that might predict a greater likelihood of acute non-renal adverse reactions. The physician’s appraisal of the efficacy of Gd-DOTA was also assessed. Results: A total of 40 adverse reactions were recorded in 32 patients, giving an overall incidence of adverse reactions of 0.93%. Gastrointestinal disorders were the most commonly reported adverse reactions (0.49%). Most adverse reactions reported were of mild intensity and no serious adverse reactions were reported. This study found that statistically significant risk factors for adverse reactions were general patient condition, liver disorder, kidney disorder, health complications, concomitant treatments, and Gd-DOTA dose (although the incidence of adverse reactions was not dose dependent). In the majority of cases (99.53%), the efficacy of Gd-DOTA was rated as ‘effective’ or ‘very effective’; only the presence of kidney disorder was associated with a significantly greater likelihood of Gd-DOTA inefficacy. Conclusion: Overall, this postmarketing surveillance study did not reveal any untoward or unexpected findings concerning the safety or efficacy of Gd-DOTA. The low incidence of adverse reactions (<1%) and the absence of serious adverse reactions reported during the survey period showed that Gd-DOTA was very well tolerated. The use of Gd-DOTA as an MRI-enhancing contrast medium in the clinical practice setting appears to be safe and effective.

Clinical results of implantation of an endovascular covered stent-graft via midsternotomy for distal aortic arch aneurysm

UNLABELLED We have been implanting endovascular stent grafts (EVG) via midsternotomy for distal aortic arch surgery since February 1997. The early clinical results are evaluated. METHODS There were 11 true aneurysms (8 fusiform, 3 saccular) and one chronic type B dissection. The average age was 68 yr (63-81). EVGs were PTFE-covered two-8 bend Z stents in the first eight cases and made with the same stents and ultrathin woven Dacron grafts in the last four cases. RESULTS Total arch replacement and aortocoronary bypass grafting were combined in one and two patients, respectively. The average retrograde cerebral perfusion time was 42+/-8 min. The cardiopulmonary bypass time averaged 211+/-26 min. All patients awoke early after operation (4.5+/-1.2 h). All but one case was extubated within 24h. There was no operative mortality, but paraplegia and cerebral infarction were complicated in one case each. Their maximum diameter (73.9+/-21.2mm) decreased significantly after operation (68.7+/-20.1mm) and one year thereafter (63.1+/-16.0 mm). True aneurysms were thrombosed completely. A chronic type B dissection revealed impending rupture due to false lumen infection one year after operation. The whole descending aorta replacement was performed but the patient died 6 months thereafter due to cerebro-vascular complication. CONCLUSION Implantation of EVGs reduces operative invasion for distal arch surgery. This procedure should improve mortality, while long-term results have not been clarified.

Real-Time Virtual Sonography, A Coordinated Sonography and MRI System that Uses Magnetic Navigation, Improves the Sonographic Identification of Enhancing Lesions on Breast MRI

This study verified that recently developed real-time virtual sonography (RVS) to coordinate a sonography image and the magnetic resonance imaging (MRI) multiplanar reconstruction (MPR) with magnetic navigation was useful. The purpose of this study was to evaluate the accuracy of RVS to sonographically identify enhancing lesions by breast MRI. Between December 2008 and May 2009, RVS was performed in 51 consecutive patients with 63 enhancing lesions. MRI was performed with the patients in the supine position using a 1.5-T imager with a body surface coil to achieve the same position as with sonography. To assess the accuracy of the RVS, the following three issues were analyzed: (i) The sonographic detection rate of enhancing lesions, (ii) the comparison of the tumor size measured by sonography and the MRI-MPR and (iii) the positioning errors as the distance from the actual sonographic position to the expected MRI position in 3-D. Among the 63 enhancing lesions, 42 (67%) lesions were identified by conventional B-mode, whereas the remaining 21 (33%) initial conventional B-mode occult lesions were identified by RVS alone. The sonographic size of the lesions detected by RVS alone was significantly smaller than that of lesions detected by conventional B-mode (p < 0.001). The mean tumor size provided by RVS was 12.3 mm for real-time sonography and 14.1 mm for MRI-MPR (r = 0.848, p < 0.001). The mean positioning errors for the transverse and sagittal planes and the depth from the skin were 7.7, 6.9 and 2.8 mm, respectively. The overall mean 3D positioning error was 12.0 mm. Our results suggest that RVS has good targeting accuracy to directly compare a sonographic image with MRI results without operator dependence.

Implantation of an endovascular covered stent-graft for distal aortic arch aneurysm via midsternotomy under pigtail catheter guidance.

We implanted an endovascular covered stent-graft for distal aortic arch aneurysm involving the left subclavian artery in 12 cases. A stent-graft was delivered just below the aneurysm via aortotomy with direct vision using a 12 F delivery sheath under guidance of a pigtail catheter placed via the groin artery. The proximal anastomosis of the stent-graft was performed with inclusion technique, and the aortotomy was then closed with it. This technique reduces operative damage by eliminating distal anastomosis and should reduce operative mortality and morbidity.

Efficacy of gastric blood supply redistribution by transarterial embolization: Preoperative procedure to prevent postoperative anastomotic leaks following esophagoplasty for esophageal carcinoma

Purpose: The aim of this study was to evaluate the effect of preoperative redistribution of gastric blood supply on the prevention of anastomotic leakage following surgical reconstruction of the esophagus.Methods: In 37 patients with esophageal carcinoma, transarterial embolization (TAE) of the left gastric, right gastric, and splenic arteries was preoperatively performed with coils so that gastric blood supply was dependent only on the right gastroepiploic artery.Results: In 34 of 37 patients, preoperative redistribution was successfully performed. The gastric tissue blood flow (TBF) of a gastric tube was higher than in 12 nonredistributed patients. Reduction in the gastric TBF during preparation of a gastric tube was 27.5% in successful patients, in contrast to 68.9% in 12 nonredistributed patients (p<0.005).Conclusion: Preoperative redistribution by TAE reduced the drop in gastric TBF during preparation of a gastric tube and helped prevent postoperative anastomotic leakage in esophageal reconstruction.