Variation in FDG uptakes in different regions in normal human brain as a function of the time (30 and 60 minutes) after injection of FDG

OBJECTIVE: The authors' goal was to determine whether FDG uptakes in various regions of the brain are different for early and late scanning time in positron emission tomography (PET). METHOD: F-18 fluorodeoxyglucose (FDG) PET was performed on 15 healthy normal subjects to obtain early and late acquisition glucose metabolic images (30 and 60 min after FDG injection), respectively. The two sets of images were compared in a voxel-by-voxel analysis. RESULTS: In the bilateral posterior cingulate gyrus, parietal and frontal association cortices, and subcallosal cortices, the FDG uptakes were larger on the late scan image than on the early scan image, and the FDG uptakes were larger in the cerebellar hemisphere, vermis and frontal basis on the early scan image than on the late scan image. CONCLUSIONS: These results suggest that there are different regional FDG uptakes depending on the scanning time after FDG injection and we must be careful in replacing conventional FDG PET scanning with early scanning in FDG PET study.     

Cerebral ischemia caused by obstructed superior vena cava cannula is detected by near-infrared spectroscopy

OBJECTIVE: Bicaval venous cannulation is being used with increasing frequency in neonates and infants to avoid circulatory arrest. However, superior vena cava (SVC) cannula obstruction may result in cerebral ischemia with no change in blood pressure or mixed venous O2 saturation. The authors hypothesized that near-infrared spectroscopy (NIRS) would allow noninvasive detection of SVC cannula obstruction. METHODS: Fifteen Yorkshire piglets (9.07 +/- 0.20 kg) underwent total cardiopulmonary bypass (CPB) (100 mL/kg/min, pH-stat strategy, hematocrit of 20%) with ascending aortic and bicaval cannulations. Femoral arterial and SVC pressure were monitored as well as mixed venous O2 saturation. NIRS monitoring of tissue oxygenation index (TOI) as well as oxyhemoglobin and deoxyhemoglobin (HHb) was undertaken. Animals were cooled to an esophageal temperature of 25 degrees C over 20 minutes. CPB flow was reduced to 50 mL/kg/min for 20 minutes. Animals then underwent a 60-minute study period of continuous CPB at 50 mL/kg/min with manipulation of the SVC cannula: group 1, open; group 2, partial occlusion; and group 3, complete occlusion. Animals were rewarmed to 37 degrees C at full flow with the SVC cannula open. Cerebral blood flow was assessed at onset of CPB, at end of cooling, at end of low flow, at end of SVC manipulation period, and at end of rewarming using radioactive microspheres. RESULTS: CBF decreased to 27.9 +/- 1.5 mL/min/100 g with complete occlusion (p < 0.01 v group 1: 39.7 +/- 1.9, group 2, 38.3 +/- 2.0 mL/min/100 g) with no change in arterial pressure or mixed venous saturation. There were also significant differences in cerebral oxygen delivery between group 3 and other groups (p < 0.01). SVC pressure increased to 19.5 +/- 4.5 and 32.5 +/- 3.1mmHg with partial and complete occlusion. NIRS indicated significant cerebral ischemia with a decrease in TOI (p < 0.05; group 3 v group 1 and 2) and an increase in HHb (p < 0.05; group 3 v group 1). At the end of the study, significant acidosis was found in group 3 compared with group 1 (p < 0.05). CONCLUSION: SVC cannula obstruction causes cerebral ischemia with no change in blood pressure or venous oxygen saturation. In view of the difficulties and risks of CVP monitoring in babies, it is recommended to use other monitoring modalities such as NIRS to assess adequacy of cerebral perfusion if bicaval cannulation is used in neonates and infants.     

Surgical treatment of liver injury with microwave tissue coagulation: an experimental study

OBJECTIVE: The purpose of this study was to examine whether microwave tissue coagulation (MTC) therapy is capable of stopping bleeding from severe liver injury in pigs. METHODS: Ten pigs (38 +/- 4 kg) underwent a 30-mL/kg isovolemic exchange transfusion with 3% low-molecular-weight dextran to produce dilutional coagulopathy, and then a through-and-through laceration injury measuring approximately 8 cm in length was induced in the right hepatic lobe. Immediately after inflicting the injury, the animals were randomly divided into two groups: Group A (n = 5, MTC was repeated along the liver laceration at intervals of 2.0 cm with manual compression) or Group B (n = 5, the injured lobe was manually compressed without MTC therapy for 1 minute). All animals received lactated Ringer's solution to maintain the mean arterial pressure at 75 mm Hg for 1 hour after the abdominal closure. The intraperitoneal blood loss, mean arterial pressure, volume of lactated Ringer's solution, and hematologic variables were compared between the groups. For further laboratory evaluation, three additional experimental animals were treated with the MTC therapy after inflicting the injury and then were allowed to survive for 14 days. RESULTS: Mean arterial pressure declined from a mean value of 88 +/- 10 mm Hg (range, 75-107 mm Hg) to 62 +/- 3 mm Hg (range, 50-75 mm Hg) after the induction of liver injury. The total blood loss in Group A was 192 +/- 58 g (range, 120-250 g), which was lower (p < 0.01) than that of 448 +/- 138 g (range, 260-650 g) in Group B. The resuscitation fluid volume of Group A animals was 304 +/- 204 mL (range, 100-600 mL), which was smaller (p < 0.01) than that of 1,320 +/- 654 mL (range, 900-2,250 mL) in Group B. At 14 days, all three animals that were treated in the additional study were found to be in good health. Their necropsies showed no evidence of an intrahepatic abscess, hematoma, or biloma. CONCLUSION: MTC therapy was thus found to provide simple, rapid, and definitive hemorrhage control in cases of severe liver injury without the need for reoperation.     

Prediction of morbidity after lung resection with risk factors using treadmill exercise test.

OBJECTIVE: To predict accurate morbidity after lung resection using treadmill exercise test. METHODS: A total of 130 patients (108 men and 22 women, with mean age 67.1+/-11.4 years (range, 34-78 years)) of 1129 patients underwent standard lobectomy were performed both treadmill exercise test and spirometry preoperatively. We measured maximum oxygen uptake/body weight (VO2max/BW) and change in arterial blood oxygen pressure from rest to symptom-limited maximum loading (delta aPaO2) and calculated exercise-induced hypoxemia (delta PaO2/delta VO2/BW), and retrospectively compared these parameters for patients with and without complications. RESULTS: There were five patients with severe postoperative complications, including three requiring use of a respirator, two with home oxygen therapy. %Vital capacity, VC (%, 80.2+/-13.2 vs. 92.5+/-20.9, P=0.026), delta PaO2 (Torr, -29.3+/-4.3 vs. -13.2+/-10.8, P=0.0004), VO2max/BW (ml/min/kg, 16.5+/-2.9 vs. 20.6+/-5.1, P=0.018) and delta PaO2/delta VO2/BW (Torr/ml/min/kg, -1.98+/-0.26 vs. -0.57+/-0.47) were significantly associated with worse outcome. All the five patients with complications had delta PaO2/delta VO2/BW<-1.7. CONCLUSIONS: Treadmill exercise testing is a good method for assessment of cardiopulmonary reserve. Limited resection must be performed if delta PaO2/delta VO2/BW is under -1.7.     

Recurrent mediastinal desmoid tumor treated by surgical resection ; report of a case

We report a rare case of mediastinal desmoid tumor in a 17-year-old man. The patient was a 17-year old man who had underwent surgery for mediastinal tumor at our hospital 2 years before. The tumor was diagnosed as a solitary fibrous tumor of the mediastinum. After 2 years, chest computed tomography(CT) and magnetic resonance imaging( MRI) showed a mass at the previously resected site. Surgery was performed again under the diagnosis of recurrent tumor. The tumor densely adhered to the superior vena cava, right innominate vein, pericardium, and the right lung. The tumor was completely resected with the aid of the partial extracorporeal circulation. Finally, both previously resected tumor and the recurrent tumor were diagnosed pathologically as desmoid tumors.     

Periductal infiltrating type of intrahepatic cholangiocarcinoma: a rare macroscopic type without any apparent mass

Purpose

This study was undertaken to elucidate the clinicopathological characteristics and surgical outcome of the periductal infiltrating (PI) type of intrahepatic cholangiocarcinoma (ICC), which is a distinct macroscopic type of ICC arising from the second-order of the intrahepatic bile ducts without apparent invasion of the surrounding liver parenchyma.

Methods

All patients with the PI type of ICC were identified from a database of patients with intrahepatic cholangiocellular carcinoma that underwent surgical resection between 1983 and 2009. The clinicopathological data of these patients were analyzed retrospectively.

Results

Sixteen of 203 patients (7.9%) had the PI type of ICC. The median survival was 7.7?years with 5-year survival rate of 62.1%. The PI type of ICC showed a significantly better survival than the mass-forming (MF) type (P?=?0.0293) or MF plus PI type of ICC (P?=?0.0001). Microscopic examinations showed intrahepatic metastasis to be absent in all the patients with PI type ICC. The incidence of intrahepatic metastases in patients with PI type was significantly lower in comparison to that of patients with MF type (P?=?0.0030) and MF plus PI type (P?=?0.0533), respectively.

Conclusion

Surgery could therefore provide a favorable outcome in patients with the PI type of ICC, probably due to its lower incidence of intrahepatic metastases.     

An internal distraction device for Le Fort distraction osteogenesis: the NAVID system

Le Fort distraction osteogenesis is sometimes applied to improve the facial appearance in craniofacial dysostosis or cleft lip and palate. Distraction devices are generally classified into external and internal types. The movement of external distractors can be controlled easily but their large size and the need for a facial mask cause much psychological stress to the patient. Internal distractors are smaller and better tolerated, but they are not easily controllable and removal is difficult. We designed an internal distraction device to eliminate the problems of the currently available distractors -Nakajima's angle-variable internal distraction (NAVID) system - and aimed to assess its clinical applicability. Between 2000 and 2010, we treated 16 patients with the NAVID system: Le Fort I, III, III?+?I and IV distractions were performed in three, five, four and four patients, respectively. Distraction was started after a 1-week latency period. Then, the exposed rod was cut, and the distractors were left in place for 3 months or more as retention devices, and thereafter removed. All patients showed satisfactory occlusion and facial aesthetics. Open bite during the consolidation period was the main complication. In conclusion, the NAVID system is safe, effective and reliable for all types of Le Fort distraction osteogenesis.     

Two-stage repair of the transposition of great arteries with interruption/coarctation of the aorta

We report on 10 patients who underwent two-stage repair of transposition of the great arteries (TGA) with interruption (IAA) or coarctation (CoA) of the aorta. First, an operation for aortic arch reconstruction was performed: Blalock-Park with pulmonary artery banding (PAB) for IAA (5 patients), subclavian flap with PAB for CoA (4 patients) and end-to-end anastomosis without PAB (1 patient). All survived the first operation and had no significant pressure gradient with good growth of the ascending aorta, except for the 1 case without PAB. Half of the 8 patients who underwent PAB developed migration of the PAB. The arterial switch operation (ASO) was performed 0.7-12.6 (5.6+/-4.7) months after the first surgery. One patient with an abnormal coronary artery tract was lost after ASO. Five developed pulmonary artery stenosis and 1 developed supra-aortic stenosis late after ASO. Two patients need reoperation, 1 for supra-aortic stenosis, and the other for reCoA. Two-stage repair for TGA with IAA/CoA is still a useful method with a good operative result. However, strict follow-up is necessary because of the high frequency of late morbidity.     

Drug delivery system using microspheres that contain tacrolimus in porcine small bowel transplantation

Rejection remains a major barrier to successful bowel transplantation, in spite of improved immunosuppressive techniques. Therefore, new, more effective, immunosuppressants, with fewer side effects, are needed. Biodegradable microspheres containing tacrolimus (FK506) were used in an experimental porcine small bowel transplantation. Twenty pigs underwent transplantation and were divided into four groups according to the immunosuppressive regimen. Group A (n=5): no immunosuppression; group B (n=6): 0.2 mg/kg per day of FK506; group C (n=3): 1.0 mg/kg per day of FK506; group D (n=6): 0.04 mg/kg per day of FK506 contained in biodegradable microspheres. Rejection was diagnosed macroscopically by endoscopic examination and histologically by biopsy specimen analysis. The mean survival time and standard deviation (SD) were 8.8±3.5, 11.0±1.4, 9.7±2.5 and 28.6±22.5 days for groups A, B, C, and D, respectively, with a statistically significant difference found between group D, on the one hand, and groups A, B and C, on the other. The mean trough blood concentration of FK506 was 10.5±2.2, 27.9±6.0 and 10.5±3.5 ng/ml in groups B, C and D, respectively. In groups A and B, all pigs died of rejection, without infection. In group C, all died of infection, without rejection. In contrast, none of the pigs in group D developed rejection or infection. Our results clearly show that the drug delivery system using biodegradable microspheres that contain FK506 is effective for controlling rejection with fewer side effects in the porcine small bowel transplantation.     

Carpentier-Edwards pericardial aortic valve in middle-aged patients comparison with the St. Jude medical valve

Objective The objective of the present study was to compare long-term results of single aortic valve replacement (AVR) with mechanical (St. Jude Medical valves: standard) and biologic (the Carpentier-Edwards pericardial) prostheses. Method: Between 1995 and 2002, 95 patients who underwent single AVR with mechanical (n=46) or biologic (n=49) prostheses were enrolled in this study. The mean age at the operation was 54.0±9.6 years (range: 20 to 69 years) with the mechanical and 68.8±7.1 years (range: 44 to 85 years) with the biologic prosthesis. Results: The 9-year actuarial survival rate, which was calculated by taking perioperative mortality into account, was 90.3±4.6% for patients with mechanical valves and 87.6 ±4.8% for patients with bioprostheses, with no difference between the two groups (p=0.342). The 9-year freedom rate from thromboembolism, reoperation, endocarditis was 94.8+3.6%, 100% and 97.8 ±2.2% for patients with mechanical valves and 98.0 ±2.0%, 97.5 ±3.4% and 95.0 ±3.4% for those with bioprostheses, respectively. After 9 years, freedom from cardiac death averaged 97.8% in the group with mechanical valves compared with 95.3% in those with bioprostheses (p=0.541). Conclusion: We conclude that the mid-term durability of the Carpentier-Edwards pericardial valve in the aortic position for the elderly is excellent. Nevertheless, the risk of tissue valve reoperation progressively increases with time, and a longer follow-up may be necessary to provide its value compared with the mechanical valves in a country like Japan with a high life expectancy. (Jpn J Thorac Cardiovasc Surg 2005; 53:465-469)