Noninvasive vessel-selective perfusion imaging with intravenous myocardial contrast echocardiography.

BACKGROUND: Intravenous myocardial contrast echocardiography (MCE) cannot identify each perfusion area of coronary vessels separately. However, by destroying microbubbles passing through a specific vessel using high-power ultrasound during intravenous MCE, vessel-selective perfusion imaging (VSPI) may be feasible. METHODS: In 10 open-chest dogs, intermittent short-axis images were obtained during contrast agent infusion using an ultrasound system. For VSPI, a probe coupled to another ultrasound machine was placed on the proximal left circumflex coronary artery (LCx). High-power ultrasound pulses were transmitted to destroy bubbles passing through the LCx. A negative contrast area on VSPI was considered to represent the perfusion area of the LCx (LCx-VSPI). A negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye were used as gold standards for defining the LCx perfusion area. LCx-VSPI was compared with a negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye. RESULTS: Despite lack of LCx occlusion, high-power destructive pulses produced a definite area of negative contrast on the LCx region. Decreased power of ultrasound pulses resulted in disappearance of the negative contrast area. An excellent relationship was demonstrated between both LCx-VSPI and a negative contrast area on conventional MCE during LCx occlusion (r = 0.93, P <.0001), and LCx-VSPI and a region without staining by Evans blue dye (r = 0.92, P =.0002). CONCLUSION: VSPI during intravenous MCE may be feasible for noninvasive assessment of perfusion areas associated with specific vessels.     

Natural and Prosthetic Heart Valve Calcification: Morphology and Chemical Composition Characterization

Calcification is the most common cause of damage and subsequent failure of heart valves. Although it is a common phenomenon, little is known about it, and less about the inorganic phase obtained from this type of calcification. This article describes the scanning electron microscopy (SEM)/energy dispersive X‐ray spectroscopy and Ca K‐edge X‐ray absorption near edge structure (XANES) characterization performed in natural and bioprosthetic heart valves calcified in vivo (in comparison to in vitro‐calcified valves). SEM micrographs indicated the presence of deposits of similar morphology, and XANES results indicate, at a molecular level, that the calcification mechanism of both types of valves are probably similar, resulting in formation of poorly crystalline hydroxyapatite deposits, with Ca/P ratios that increase with time, depending on the maturation state. These findings may contribute to the search for long‐term efficient anticalcification treatments.     

A new approach to percutaneous transhepatic portal embolization using ethanolamine oleate iopamidol

Purpose

We aimed to examine the therapeutic efficacy of ethanolamine oleate iopamidol (EOI) as an embolic material for percutaneous transhepatic portal embolization (PTPE).

Methods

Eighty-two patients with liver tumors were treated with PTPE. Fifty-eight patients had hepatocellular carcinomas, 11 had liver metastases, and 13 had other liver tumors. A total of 55 patients (group E) were treated with 5% ethanolamine oleate after gelatin sponge administration. As a control, we evaluated 27 patients (group F) who were treated with fibrin glue and iodized oil. PTPE was mainly indicated before hepatic resection, for patients with high nontumorous volumetric resection ratios (the nontumorous volumetric resection ratio was estimated to be greater than 65% in patients with an indocyanine green retention ratio of 15 min (ICG R15) of 10% or less, and the nontumorous volumetric resection ratio was estimated to be greater than 40% in the patients with an ICG R15 of 10–20%).

Results

All patients were successfully treated percutaneously under local anesthesia. Balloon-occluded and ipsilateral approaches were used in 81 patients (99%) and 62 (75%) patients, respectively. The rate of insufficient embolization or recanalization was significantly lower in group E (7.3%) in comparison to group F (25.9%; p < 0.05). The volumetric resection ratios, before and after PTPE, decreased from 60 to 45% in group E and from 63 to 55% in group F. The post-PTPE resection ratio was significantly decreased in group E. Before and after PTPE, average ICG R15 values changed from 17 to 27% in group E and from 18 to 26% in group F. The complication rates in groups E and F were similar (7.3 vs. 7.4%).

Conclusion

EOI is a safe embolic material that can be used to induce greater liver hypertrophy, in comparison to fibrin glue, in PTPE for liver tumors.     

β-galactosidases from jack bean and Streptococcus have different cleaving abilities towards fucose-containing sugars

We examined the sugar-cleaving abilities of β-galactosidases from jack bean and Streptococcus towards sugars containing fucose residues, and found that jack bean β-galactosidase has an ability to cleave the β1-3 linkage between galactose (Gal) and fucose (Fuc) residues, but not β1-4 linkage. On the other hand, streptococcal β-galactosidase was found to cleave the linkage in both Galβ1-4Fuc and Galβ1-3Fuc disaccharide units. Such a difference in sugar-cleaving abilities between these 2 β-galactosidases will be useful for structural analysis of glycans, especially those from species belonging to Protostomia, such as Caenorhabditis elegans.     

Double-subtraction maximum intensity projection MR angiography for detecting the artery of Adamkiewicz and differentiating it from the drainage vein

PURPOSE: To evaluate the efficacy of double-subtraction magnetic resonance angiography (MRA) (subtraction of the subtracted venous phase image from the subtracted arterial dominant phase image) for depicting the artery of Adamkiewicz and differentiating it from the drainage vein. MATERIALS AND METHODS: A total of 170 patients (123 men, 47 women; aged 17-84 years, mean = 67 years), with a thoracoabdominal vascular lesion underwent MRA for detection of the artery of Adamkiewicz. MRA was performed as a five-phase dynamic-enhanced three-dimensional (3D) fast spoiled gradient recalled acquisition in steady state (GRASS) sequence on a 1.5-T system, with double-dose bolus contrast and saline injection. The levels at which the artery of Adamkiewicz and drainage vein originated were determined. Signal intensities of the two vessels were measured with source images to assess the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and necessity of the double-subtraction technique. RESULTS: The artery of Adamkiewicz was detected in 140 patients (82.4%). Branching occurred at levels T8-T12 on the left and T8-T11 on the right. An additional anterior radiculomedullary artery was detected in 18 patients. The drainage vein was detected in 133 patients (78.2%). It merged at the T9-L2 level on both sides. In six of the 133 patients (4.5%), the drainage vein branched upwardly. Neither SNR nor CNR differed significantly between the artery of Adamkiewicz and the drainage vein in the arterial phase; but on the subtraction image, signal intensity of the artery was higher than that of the drainage vein (P < 0.05). CONCLUSION: Double-subtraction MRA is useful for detecting the artery of Adamkiewicz when it is necessary to differentiate it from the drainage vein.     

Case of cerebral salt wasting syndrome with difficulty in controling excessive urine volume

Symptoms of hyponatremia and diuresis due to cerebral salt wasting syndrome (CSWS) are often observed after aneurysmal subarachnoid hemorrhage (SAH). Inadequately treated CSWS is known to work as a trigger of symptomatic vasospasm in SAH patients. Therefore, it is indispensable to detect and treat CSWS as early as possible in ICU. A 36-year-old man with SAH was admitted to our ICU. His urine volume increased excessively 3 days after ICU admission, and it reached a peak (39,250 ml x day(-1)) on the 6th day in ICU. Since infusion volume was controlled with regard to daily urinary output, hyponatremia was not noticeable and excessive urine volume stood out conspicuously. Though vasopressin and desmopressin were administered, the symptoms of natriuresis and hyponatremia were aggravated, associated with hyper secretion of natriuretic peptides (ANP 160 pg x dl(-1), BNP 172 pg x dl(-1)). Recent studies revealed that hyponatremia and hypovolemia following SAH might be caused by exaggerated secretion of natriuretic peptides. Experimental studies showed that the administration of vasopressin and desmopressin cause excessive secretion of natriuretic peptides under the circumstance of volume expansion in rats. We infer that the administration of vasopressin and desmopressin to our patient deterionated natriuresis in CSWS as in the previous experimental findings.     

Radiofrequency ablation with hand-assisted laparoscopic surgery for the treatment of hepatocellular carcinoma in the caudate lobe

OBJECTIVE: To assess the feasibility and safety of radiofrequency ablation (RFA) with hand-assisted laparoscopic surgery (HALS) for hepatocellular carcinoma (HCC) in the caudate lobe with severe liver dysfunction. SUMMARY BACKGROUND DATA: HCC in the caudate lobe remains one of the most difficult locations where various treatments tend to pose problems regarding the optimal surgical approach. The technique of HALS has thus been proposed as a useful method for performing a safe RFA therapy. For this study, we assessed the feasibility and safety of RFA with HALS for the treatment of HCC in the caudate lobe with liver dysfunction. PATIENTS AND METHODS: Between July 1999 and February 2005, 5 patients who suffered from HCC in the caudate lobe were indicated for RFA. The percutaneous puncture was difficult and all patients have severe liver dysfunction with viral chronic hepatitis. Therefore, RFA was assisted by an inserted hand through a minimal skin incision under laparoscopic inspection. An intraoperative endoscopic ultrasound examination was performed before RFA to determine the tumor region. The hand-assisted minimal dissection around the caudate lobe was required to detect tumor and avoid injuries of other tissues. RFA for HCC was performed using a cooled-tip (Radionics Inc, Burligton, MA) connected to a RF generator under the programmed cyclic impedance. RESULTS: The surgical procedures consisted of 5 RFA to tumors in the caudate lobe with HALS, which was performed safely, and a postoperative computed tomography scan revealed a sufficient ablation in all patients. There was no operative mortality but 1 patient had minor bile leakage, which was treated conservatively, and all patients recovered and thus were eventually discharged. One patient had local recurrence after 3 months, 3 patients had tumor recurrences in another segment after 6 months. At a mean follow-up 32.2 months, all patients were still alive. CONCLUSIONS: RFA with HALS is considered to be a safe and feasible technique for HCC in the caudate lobe with liver dysfunction.     

Two cases of stage IV gastric cancer responding to chemotherapy with S-1 or UFT

We report patients with advanced Stage IV gastric cancer responding to chemotherapy with S-1 or UFT. Case 1: The patient was a 59-year-old man with Stage IV gastric cancer because of CY 1. After surgery, chemotherapy with S-1 (100 mg/body/day) was performed for one year and 11 months. At present, 5 years and 5 months after surgery, this patient shows no signs of tumor recurrence. Case 2: The patient was a 68-year-old woman with Stage IV gastric cancer because of P 1. She was treated with 200 mg/day of UFT for one year and 9 months. At present, 5 years after surgery, she shows no signs of tumor recurrence. We considered that the longterm survival of such patients is attributable to chemotherapy with S-1 or UFT. The OPRT activity of the two cases was high, so chemotherapy with S-1 or UFT was thought to be effective for them.