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G Pistorius

Publications and source records attributed to G Pistorius.

33 records · Page 2Linked to original sources
PubMed1997

Long-term function of experimental substitutes of the ileocecal valve.

The bacteriological barrier function of the ileocecal valve (ICV) can be replaced according to the principle of the nipple-valve anastomosis. Since late complications due to technical measures for stabilizing the ileal nipple have been hitherto unknown, 12 adult beagle dogs were operated on by three technical modifications of a nipple-valve anastomosis and were followed up for 1 year: In three cases the ileal nipple was stabilized by longitudinal staples (NVA), in three cases an intestinal neosphincter (INS) was produced by healing of the muscular layers between the ileal nipple and colon, and in six cases an oral zone of stabilization, preserving an aboral valve zone (S-NVA) was constructed. Measures for valve function at the end of the study period were the weight course of the animals and the intestinal bacterial profile, considering morphological complications of the substituted valves. As reference the respective bacterial counts in ICV and end-to-end anastomosis (EEA) were used, which had been determined in the same animals in earlier experiments. Following an initial increase in weight the 3 animals with NVA and the three animals with INS continuously lost weight from the 4th postoperative month onward. The 6 animals with S-NVA, however, showed from the 4th postoperative month onward a significantly higher weight level (p < 0.05), which remained constant up to the end of the 1-year observation period. Because of a morphologically intact structure of the substituted valve a significantly (p < 0.05) better bacteriological clearance of the ileum was confirmed in these animals after 12 months when compared with the EEA group. In contrast, in the NVA and INS animals a severe bacterial overgrowth of the entire small intestine was observed. This was caused by an intestinal stagnation due to partial prolapse of the nipple in NVA and due to fibrotic stenosis in INS. The results of our study suggest that technical measures to relieve the tendency to devaginate are only successful, if they do not lead to obstruction of the orthograde intestinal passage in the long term. Thus, only the clinical introduction of the S-NVA model may be justified.

Animals↗
PubMed1996

Bilateral vertebral artery lesion after dislocating cervical spine trauma. A case report.

STUDY DESIGN: This case report illustrates the problems associated with diagnosis and management of vertebral artery injuries resulting from dislocating cervical spine trauma. OBJECTIVES: Treatment involved the principles of anterior stabilization of dislocating cervical spine fracture as well as the diagnostic procedures and therapeutic modalities appropriate for vertebral artery lesions. SUMMARY OF BACKGROUND DATA: Because vertebral artery injuries with cervical spine trauma are rarely symptomatic, they can easily be overlooked. Bilateral or dominant vertebral artery occlusion, however, may cause fatal ischemic damage to the brain stem and cerebellum. METHODS: Cervical spine dislocation was stabilized immediately after admission using internal fixation by ventral plate and corticocancellous bone graft. Immediate angiography was performed when brain stem neurologic dysfunction manifested 36 hours after surgery. The patient was treated with anticoagulation, osmotherapy, and controlled hypertension. RESULTS: A fatal outcome resulted in this case of dominant left vertebral artery occlusion. Necropsy even revealed bilateral vertebral artery damage at the level of the osseous lesion. CONCLUSIONS: The possibility of the complication of a vertebral artery lesion should be kept in mind when examining patients with cervical spine trauma, especially in patients with fracture-dislocation. Immediate identification by vertebral angiography, magnetic resonance imaging, or thin-slice computed tomography scan is necessary for optimal management of this injury.

Adult↗
PubMed1996

First experience with laparoscopic spine fusion in an experimental model in the pig.

BACKGROUND: We elucidated whether anterior lumbar spine fusion with interbody implants (BAK) can be performed in an experimental model in the pig using a transperitoneal laporoscopic approach. METHODS: In seven animals, a pneumoperitoneum with an intraabdominal pressure of 12 mmHg was induced, and five trocars were placed in the middle, as well as in the left and right lateral aspect of the abdomen. With the use of specially designed instruments, the bifurcations of the aorta and vena cava were prepared. The sacral artery, overlying the anterior aspect of the L5/S1 disc space, was retracted, allowing the exposure of the disc space. A working trocar was then fixed to the spine bodies above (L6) and below (S1) the disc, and instrumentation was completed by destruction of the disc, insertion of distraction plug, and implantation of the BAK cage. X-ray control allowed exact positioning of the cage. RESULTS: There were no major complications during the operative procedure, in particular no bleeding from major blood vessels and no injury to intraperitoneal organs. Cages were implanted in all animals in correct position, as indicated by postoperative X-ray control. CONCLUSIONS: We conclude from our experiments that in the pig model implants for anterior interbody lumbar spine fusion can be inserted successfully using the laparoscopic approach. We propose that the pig model represents an ideal tool for training before applying this operative procedure in men.

Animals↗
PubMed1996

[Laparoscopic 2-level fusion of the lumbar spine with Bagby and Kuslich implants].

In a 50-year-old female patient, presenting with permanent low lumbar back pain and intermittent neurological alterations due to degenerative disc disease L4-5 and L5-/S1 we demonstrate that two-level anterior interbody fusion can be performed via laparoscopic transabdominal instrumentation using BAK interbody implants. Intervertebral disc space L5-/S1 was stabilized approaching the spine caudally of the aortic bifurcation, while disc space L4-L5 required an approach from the left lateral aspect, mobilizing the aorta and vena cava to the right. The postoperative course was without complications and allowed discharge from the hospital on day 8. X-ray control 4 months later demonstrated restoration of adequate disc space at L4-L5 and L5-/S1 and appropriate positioning of the implants.

Female↗
PubMed1996

[Laparoscopic resections in colon carcinoma].

Since 1992 laparoscopic-assisted resections have been performed in 43 patients with tumors of the right or left colon. Excluding one patient with anastomotic leak there were no harvest complications. After a mean follow-up of 25 months 26/39 patients are living without tumor progress or recurrence, none of the 39 patients have abdominal wall metastases as yet; nine patients died due to tumor progress.

Adult↗
PubMed1995

[Laparoscopic resections in Crohn disease].

39 patients with Crohn's disease underwent laparoscopic bowel resections during January 1993 to May 1995 (16 female, 23 male, with an average age of 33 years). The duration of the disease ranged from one to 18 years. 21 of the 39 patients were under steroid therapy at the time of operation. Seven patients have had ileocaecal resection for Crohn's disease. The operative technique is laparoscopically assisted. We performed: small bowel resections (8), ileocaecal resections (16), hemicolectomies (11), subtotal colectomies (2), colectomies (2). Operative time ranged from 90 to 280 min for ileocaecal resections and from 330 to 420 min for colectomies. Intraoperative complications were not encountered. Postoperatively one patient developed a subhepatic abscess which was drained under sonographic guidance on day 6. One patient was reoperated for a different disease on postoperative day 2. Two patients had fever till day 9 and 13 without clinical relevance. Two patients had delayed incision site healing. Postoperative clinical stay was 11 days. The main benefit for the patients was early mobilisation due to reduced pain. Patients experienced the small abdominal incision as a ray of hope in their chronic disease.

Adolescent↗
PubMed1995

[Technique and quality of laparoscopic hand-sewn intestinal anastomoses in an experimental procedure].

In conventional surgery running suture of all intestine layers is used commonly. Therefore we have tested the following manual running suture technics for laparoscopic surgery using animal experiments. 1. Turnover technic: suture of front and back-wall from outside by using holding sutures. 2. Non-turnover-technic: special holding sutures to fix the back-wall and sewing from the inside followed by the front-wall from outside. 3. Clamp-technic: By using two special parallel closing clamps (Endo-Gauge) with a suture from inside and outside. The ends of the anastomosis are well fixed without additional suture. All animals (n = 15) survived without complications, without leakage of the anastomosis and only one third developed intraabdominal fusions. The main difference was in time performing the anastomosis: 64 min. for the turnover technic, 52 min. for the non-turnover technic and only 25 min for the clamp technic without holding sutures. According to this results, we start to design a new bowel-clamp for sewing laparoscopic anastomosis. Therefore it is possible to perform a laparoscopic manual running suture in a reasonable amount of time. Furthermore the laparoscopic manual suture is a good alternative to the stapler technic because it is much less expensive and leaves no foreign materials.

Anastomosis, Surgical↗
PubMed1995

[Bacterial clearance of the terminal ileum in relation to the ileocolic connection].

The ecology of the (neo-)terminal ileum was investigated in three groups of mongrel dogs (group 1 to 3; 6 animals per each group) depending on the ileocolic connection and the resection of the terminal ileum. The efficacy of a stabilized nipple-valve-anastomosis (SNVA) was evaluated comparing the physiological ileocecal valve and the conventional end-end-anastomosis. The relations of the aerobic and anaerobic bacterial counts of all 18 dogs (group 0) preoperatively served as reference-values. Under this physiological condition the median counts were found to be lower in the ileum than in the colon, two logs for the aerobic bacteria and three logs for the anaerobic bacteria, confirming statistical significance (p < or = 0.05). The resection of the terminal ileum conserving the ileocecal valve (group 1) had no influence on the bacterial flora of the neoterminal ileum, whereas the limited resection of the ileocecal valve with ileocolic end-end-anastomosis (group 2) induced a bacterial colonisation of the terminal ileum. In contrast, following wide ileocoecal resection and replacement of the ileocecal valve by the SNVA (group 3) the bacterial counts were lower in the terminal ileum than in the colon: five logs for aerobic and seven logs for anaerobic bacteria. This difference was statistically significant within this group between ileum and colon and between ileum preoperatively and postoperatively (p < or = 0.05). In conclusion, the bacterial clearance of the (neo-)terminal ileum depends more on the retrograde barrier-function of the ileocecal valve or an appropriate mechanical substitute than on the propulsive motility of the ileum.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1994

[An intestinal neosphincter attained by circumscribed muscle proliferation. Technical development and functional evaluation in the dog].

In an experimental study an intestinal neosphincter (INS) was constructed by modifying the principle of the ileocolic nipple-valve anastomosis by means of ultrasonic tissue fragmentation of the contacting serosa of the ileum and the corresponding mucosa of the ileum and colon. The healing of the muscle layers was studied histologically. The function of the INS was investigated in six dogs and compared intraindividually with that of the ileocecal valve and conventional end-to-end anastomosis. Morphologically the neospincters healed within 3 months without major fibrosis. The reference values of the aerobic and anaerobic bacterial counts in the terminal ileum were more than 2 logs lower than in the colon with the normal ileocecal valve, and after ileo-colonic end-to-end-anastomosis bacterial colonization of the terminal ileum was found both qualitatively and quantitatively. Subsequent interposition of the INS led to bacterial clearance of the terminal ileum. The median aerobic bacterial counts were lower by six logs and the an aerobic bacterial counts by 3 logs than in the colon. However, differences were not statistically significant owing to the wide variation in the individual values. Nevertheless, the demonstrable clearance of the terminal ileum could be explained by the orthograde passage with absolutely no stagnation and the relative competence of the INS in resisting retrograde pressure competence. In conclusion, ultrasonic fragmentation of the serosa and mucosa of the bowel allows construction of an INS from three muscle layers, which acts as a bacteriological barrier. Before it is introduced into the clinical setting its integration into the intestinal motility should be evaluated by further studies.

Anastomosis, Surgical↗
PubMed1989

Pancreatic autotransplantation in the pig: variations in epigastric arterial blood supply.

A major problem in pancreatic autotransplantation is the vascular supply of the left segment, which serves as the graft. We therefore examined the arterial blood supply of the epigastric organs in 36 German landrace pigs. In 19 pigs (anatomical variation 1) there was a pancreatic branch of the splenic artery supplying the left segment. After splenectomy the splenic artery could be used as the graft-supplying vessel. In 14 pigs (anatomical variation 2) the arterial branch for the left segment was the first branch out of the hepatic artery distal to the coeliac trunk. In these cases a splenohepatic bypass was performed to ensure delivery of the blood to the epigastric organs. Thereafter, the proximal part of the hepatic artery could be used as the vessel supplying the graft. The left segment could not be used for autotransplantation in 3 pigs (anatomical variation 3) because of the atypical vascular supply. During the 6-month observation period, no malfunction of the epigastric organs was evident.

Animals↗
PubMedDate not supplied

Tumor-specific methylation patterns of erbB2 (HER2/neu) sequences in gastro-intestinal cancer.

To determine whether the sporadically occurring amplification of the oncogene erbB2/HER2 in gastrointestinal carcinomas is associated with additional changes of this sequence, DNA from 17 colorectal and 5 stomach carcinomas was analyzed for copy number, sequence rearrangement and DNA methylation by Southern blot hybridization. Amplification was detected in two cases. By applying the isochizomers Hpall and Mspl we tested for alterations in the DNA methylation status. Whereas in colon tumors with non-amplified erbB2 this status was unchanged, one case with erbB2 amplification showed additional MspI bands indicating a methylation of the amplified gene sequences. In stomach carcinoma, however, we detected differences between tumor and mucosa samples but not between amplified and non-amplified tumor samples. Independent of the DNA methylation status, significant amounts of the erbB2 oncoprotein were detected in the cases with gene amplification; weaker immunostaining of erbB2 was also seen in a few additional tumors.

Blotting, Southern↗