Potential of noncontrast electrocardiogram-gated half-fourier fast-spin-echo magnetic resonance imaging to monitor dynamically altered perfusion in regional lung

RATIONALE AND OBJECTIVES: The potential of a noncontrast, electrocardiography (ECG)-gated fast-spin-echo (FSE) MR imaging (MRI) to monitor dynamically altered regional lung perfusion was assessed in acute and temporal pulmonary embolic and airway obstruction dog models. MATERIALS AND METHODS: After acquisition of ECG-gated multiphase FSE MR images during one cardiac cycle, the two phase images of the minimal lung signal intensity (SI) during systole and the maximal SI during diastole were acquired in the lower lung levels in six normal dogs, in 13 dogs before and for 35 minutes after temporal microvascular embolization in regional lungs with gradually degradable starch microspheres of spherex, and in 12 dogs before and for 45 minutes after bronchial occlusion with a balloon catheter. In three of the 13 embolic models, the opposite lung areas, however, were permanently embolized with enbucrilate. Subtraction between the diastolic and systolic images yielded a perfusion-weighted image. The results were compared with a gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced dynamic perfusion MRI, which was subsequently performed after the ECG-gated MRI in each animal. RESULTS: The multiphase FSE images provided cardiac-dependent pulsatile lung SI changes, and the subtracted perfusion-weighted images provided a uniform perfusion map in normal lungs. In all the embolic models, the subtracted perfusion-weighted images showed gradual disappearance of the spherex-induced perfusion deficits, while the enbucrilate-induced perfusion deficits persistently remained in the three animals. In all airway obstruction models, these images showed gradually decreased perfusion in the hypoventilated areas. These results were consistent with the matched Gd-DTPA-enhanced pulmonary arterial perfusion phase images in each animal. CONCLUSION: This noncontrast perfusion MRI may have excellent potential for continuously monitoring dynamically changed regional lung perfusion within a short time on its high spatial resolution cross-sectional images.     

CT findings of leukemic pulmonary infiltration with pathologic correlation

The aim of this study was to demonstrate the characteristic CT findings of leukemic pulmonary infiltration based on the pathologic findings. The CT findings of 11 leukemic patients with leukemic pulmonary infiltration were compared with those of 22 leukemic patients with other diseases as a control group. Evaluated pulmonary parenchymal CT findings included thickening of bronchovascular bundles and interlobular septa, prominence of peripheral pulmonary arteries, ground-glass opacities, air-space consolidation, and nodules. The CT-pathologic correlations for leukemic infiltration were evaluated in 7 patients. Frequent parenchymal CT findings were thickening of bronchovascular bundles (81.8%), prominence of peripheral pulmonary arteries (81.8%), and non-lobular and non-segmental ground-glass opacities (90.9%). The first two findings were significantly more frequently observed in leukemic infiltration than in the control group, had good interobserver agreement, and corresponded pathologically to leukemic cell infiltration around the pulmonary arteries, bronchi, or bronchioles. Non-lobular and non-segmental ground-glass opacity corresponded to leukemic cell infiltration within alveolar spaces and septa adjacent to the pulmonary arteries or bronchi and also corresponded to hemorrhage, edema, or diffuse alveolar damage. Thickening of bronchovascular bundles and prominence of peripheral pulmonary arteries are CT findings suggestive for leukemic infiltration and correspond to peribronchovascular tumor extension.     

Appendicitis caused by caecal carcinoma: report of a case

Appendicitis can rarely occur in association with carcinoma of the caecum, particularly in elderly patients. We report a case of acute appendicitis provoked by an adenocarcinoma of the caecum which obstructs the lumen of the appendix in a 58-year-old man. The patient underwent an ileocaecal resection with lymph node dissection. The difficulties of identifying a small tumor at laparotomy and the implication for optimal treatment are emphasized.     

Easier hepatic resections with a straight needle

BACKGROUND: A stainless-sheathed, straight needle with a hook near the top of the inner needle was designed to facilitate hepatic resections. METHODS:First, using this needle, two rows of interlocking mattress sutures were made along the division line; then, hepatic transection was performed between these rows by electrocautery or forceps. RESULTS: Since 1997, we have performed this kind of hepatic resections in 43 cases, including 9 right lobectomies, 5 bisegmentectomies, 7 segmentectomies, 4 subsegmentectomies, 2 partial hepatectomies, 15 left lateral segmentectomies, and 1 hepatorrhaphy. In most cases, intraoperative hemorrhage was minimal. Neither specified inflow nor backflow control procedures were needed. CONCLUSION: Use of this needle may reduce the difficulty of the technique and blood loss for right hepatic lobectomy, left lateral segmentectomy, and some segmental or partial hepatectomy procedures.     

Esophageal resection in elderly esophageal carcinoma patients: improvement in postoperative complications

BACKGROUND: Advanced age is considered to be a relative contraindication for radical esophagectomy with a three-field lymph node dissection. METHODS: Preoperative risks, postoperative morbidity and mortality, and long-term survival in 55 elderly patients (> or =70 years) who had undergone extensive esophagectomy for esophageal carcinoma were compared with those of 149 younger patients (<70 years). RESULTS: Elderly patients had worse preoperative cardiopulmonary function and had more frequent postoperative cardiopulmonary complications compared with younger patients (p < 0.05). The postoperative death rate was not statistically different between the elderly (10.9%) and younger groups (5.4%). When the study period was divided into an early and a late phase, the postoperative death rate dropped significantly (p < 0.05) in recent years (1.4%) when compared with the previous era (10.0%). The overall survival rates were not different between elderly and younger patients. CONCLUSIONS: Preoperative cardiopulmonary risk factors and postoperative complications after esophagectomy were more frequently noticed in elderly patients than in younger patients. A dramatic improvement in postoperative death was noticed in recent years. The long-term survival of elderly patients after extended esophagectomy was almost similar to that in younger patients.     

Body mass index determines the success of lymph node dissection and predicts the outcome of gastric carcinoma patients

We tried to determine the role of the body mass index (BMI) on the extent of lymph node dissection in gastric cancer surgery. Seven hundred and eighty-seven patients with gastric carcinoma were reviewed. Ninety-two (11%) patients exceeded the upper limit of the optimum BMI. Significantly fewer lymph nodes were removed following D2 (p = 0.002) and >/=D3 (p = 0.023) dissections, and the lymph node ratio was significantly (p = 0.0383) higher in overweight patients. The recurrence-free survival was significantly (p = 0.0297) shorter in T2/T3 cases with high BMI, and BMI (relative risk 1.85) became an independent prognostic factor in multivariate analysis. Higher BMI hampers regional lymph node dissection in gastric cancer patients and became an independent predictor of disease recurrences in T2/T3 gastric cancers.     

The use of chitin as a new absorbable suture material—An experimental study

A comparative study of four absorbable suture materials, namely; poly-N-acetylglucosamine (Chitin), polyglycolic acid (PGA), plain catgut and chromic catgut, in terms of strength, elongation, tensile strength retention and tissue reaction, was undertaken. The straight pull strength of USP 3–0 size Chitin was over 2.6 kg, compared with PGA, which was over 3.4 kg and the catguts, which were over 2.0 kg. Chitin showed the lowest elongation among the four. The tensile strength retention (TSR) of Chitin in muscle was 45 per cent at 14 days and 7 per cent at 25 days, which was similar to that of PGA. The TSR of Chitin was maintained by 35 per cent in gastric juice, 97 per cent in bile and 100 per cent in pancreatic juice after immersion for 30 days. The corresponding values for PGA were 54 per cent, 0 per cent and 0 per cent, respectively, whereas both catguts had dissolved within 30 days. The tissue reaction of Chitin was similar to that of PGA, whereas the catguts caused more intense tissue reaction.     

Sheath proteins: synthesis,secretion, degradation and fate in forming enamel

We investigated expression of ameloblastin and sheathlin, recently cloned enamel matrix proteins from the rat and pig, in forming enamel immunocytochemically and immunochemically, using region-specific antibodies. The results obtained from the rat and pig were essentially the same. Antibodies which recognize the N-terminal region stained the secretory machinery of the secretory ameloblast and the entire thickness of the enamel matrix, especially the peripheral region of the enamel rod. Immunostained protein bands were observed near 65 or 70 kDa and below 20 kDa. C-terminal-specific antibodies stained the secretory machinery of the ameloblast and the immature enamel adjacent to the secretion sites. Immunostained protein bands were found ranging from 25 to 70 kDa. Antibodies which recognize a region in the protein just prior to the C-terminal region stained the cis-side of the Golgi apparatus but not the enamel matrix. Immunostained protein bands were observed of about 55 kDa. These results suggest that post-translational and post-secretory modifications of ameloblastin and sheathlin are similar to each other, and further showed that their cleaved N-terminal polypeptides concentrate in the prism sheath. We propose that sheathlin and ameloblastin share the same role in amelogenesis and should be classified as sheath proteins.