Cryoscience and cryomedicine: new mechanisms of biological tissue injury following low temperature exposure. Experimental study.

UNLABELLED: A number of theoretical and experimental studies, both in vitro and in vivo, have been performed to explain the action of low temperatures on tissue. It is now evident that the thermal parameters used in the past for freezing during cryosurgery were not precise; this may have resulted in the failure of treatment. For the first time, this report describes the early ultrastructural features of pancreatic parenchyma after low temperature exposure, i.e, cryosurgery, in vivo. MATERIALS AND METHODS: Of investigation 48 animals were used for the experiment. A temperature range of -80 degrees C and -180 degrees C in contact with pancreas tissue was selected for cryosurgical exposure. The cryosurgical response of pancreas parenchyma, i.e. ultrastructural cellular changes in pancreas tissue, was investigated. For transmission electron microscopy, the specimens from the pancreas parenchyma were taken immediately, one hour and 24 hours after the finishing of the freeze-thaw cycles intraoperatively. RESULTS: The electronic microscopic analysis showed that, after local cryodestruction at temperatures of -80 degrees C and -180 degrees C, similar processes occurred within the pancreas tissue in the early postcryosurgical phase-immediately and up to 24 hours after low temperature exposure on tissue. The exocrine pancreatic cells in the center of the cryozone changed upon thawing. Ultrastructural changes in the exocrine pancreatic cells, where the first signs of dystrophic processes had been noticed, were increased. These ultrastructural changes in the pancreatic cells provide a platform to better understand the mechanisms of damage and the pathogenesis of frostbite after cryosurgery. The properties of the pancreas parenchyma response after low temperature exposure provide important insights into the mechanisms of damage and the cryogenic lesion immediately after thawing in cryosurgery. CONCLUSION: Our new insights prove on the cell level that suddenly and progressively damaged pancreatic cells in the postcryosurgical zone lead to aseptic cryonecrosis and then to aseptic cryoapoptosis of vital normal tissue. The vascular capillary changes and circulatory stagnation demonstrate the anti-angiogenesis mechanism, which, together with cryonecrosis and cryoapoptosis, are some of the main mechanisms of biological tissue injury following the low temperature exposure.

Improving the safety of laparoscopic cholecystectomy: the routine use of preoperative magnetic resonance cholangiography.

BACKGROUND: The aim of this study was to determine the value of routinely performed preoperative magnetic resonance cholangiography (MRC) in detecting common bile duct (CBD) stones in patients stated to undergo elective laparoscopic cholecystectomy. In addition, we used MRC to investigate possible variants of the cystic duct. METHODS: Magnetic resonance cholangiography was performed preoperatively in 773 patients (311 male and 462 female; median age 55 years, range 16-91) who had no clinical signs of cholestasis prior to undergoing elective laparoscopic cholecystectomy. In cases where the MRC was positive for CBD stones, endoscopic retrograde cholangiopancreatiography (ERCP) was then performed. A total of 532 patients were available for continuous postoperatively follow-up (median 54 months, range 36-85). In 462 patients (247 female, and 215 male), MR images were also reviewed for variants of the cystic duct. RESULTS: In 705 patients (91%), MRC was negative for CBD stones. In 64 patients (9%) MRC was positive. Of these patients, 47 (6%) had CBD stones on ERCP. In 12 patients (2%), MRC was false positive. In five cases (0.6%), ERCP had an inconclusive result postoperative follow-up (532 patients, or 69%) revealed evidence of CBD stones in three patients (10.4%) despite a preoperative negative MRC result. Anatomical variants in the course of the cystic duct and its confluence with the common bile duct were found in 27 of 462 patients (6%). CONCLUSIONS: Magnetic resonance cholangiography proved to be a reliable screening technique in the preoperative evaluation of patients with silent CBD stones. Imaging of the course of the cystic duct is possible in a high percentage of cases. Therefore, MRC can be recommended as a screening technique before laparoscopic cholecystectomy.

[Collateral circulation of the left colon: historic considerations and actual clinical significance]. / Die kollaterale Gefässversorgung des linken Hemikolons. Historische Beobachtungen und aktuelle klinische Bedeutung.

INTRODUCTION: The arterial communication between the superior and inferior mesenteric arteries is important in surgery of the colon and aorta. METHODS: The anastomosis between the median colic artery (ACM) and the superior colic artery (AMS) was studied on 52 cadavers (32 female, 20 male). The length of the artery was measured using a flexible scale, and its diameter was determined at three different locations (origin, middle, end). RESULTS: The median lengths of the arteries were: 6.8 cm (range 3.9-9.7) for ACM, 12.2 cm (range 7-17.4) for ACS, and 23 cm (range 13.6-34.2) for margin artery. The median diameters were: 3.4 mm (range 2.7-4.1) for ACM, 3.1 mm (range 2.1-4.1) for ACS, and 2.7 mm (range 2-3.4) for margin artery. In 9.6% of the cadavers ( n=5), additional anastomoses between the AMS and inferior mesenteric arteries were proven. In 90.4% ( n=47), only margin arteries were found. SUMMARY: The low incidence of an additional communication (Riolan's arch) and possible additional impairment of the blood supply should be taken into account during operation.

Needle perforation of the appendix.

BACKGROUND/AIMS: Needles are among the most frequently swallowed foreign bodies. In most cases they are excreted per vias naturales, but in some cases needles can lead to perforation of the stomach or duodenum in adults. METHODS: We report a case of acute appendicitis after perforation of the appendix by a swallowed needle. An appendectomy was performed without any knowledge of the reason for perforation. RESULTS: Inspection of the resected appendix demonstrated a needle of 1.5 cm length inside the lumen of the appendix, which had caused a perforation of the distal end of the appendix. CONCLUSION: As seen in this case a longer-lasting nondiagnosed perforation can lead to extensive local inflammation which could have been avoided by early surgical treatment which should also be considered if the patient has very few symptoms, as in this case.