Am J Surg. 2006 Jul;192(1):76-81.
Effects of a static magnetic field on wound healing: results in experimental rat colon anastomoses.
Nursal TZ, Bal N, Anarat R, Colakoglu T, Noyan T, Moray G, Haberal M.
Department of General Surgery, Adana Teaching and Research Center, Baskent University, Dadaloglu Mah. 39. Sok. No. 6, 01250 Yuregir Adana, Turkey. tznursal@baskent-adn.edu.tr
Abstract
BACKGROUND: Research has shown that pulsed electromagnetic fields (EMFs) promote wound healing in experimental colonic anastomosis; however, the effects of static EMFs in this setting have not been investigated to date.
METHODS: Fifty male Wistar rats were used. Ten served as controls for mechanical strength testing, and the other 40 underwent descending colon resection and anastomosis. Twenty of these 40 animals (M group) had NeFeB magnets placed in contact with the anastomosis site (magnetic field strength at the site 390 to 420 G). The other 20 animals (sham [S] group) had non-magnetized NeFeB bars of the same dimensions and weight implanted. Half of the animals in each group were killed and assessed for healing parameters on postoperative day 3 (M3 and S3 groups) and the other half on postoperative day 7 (M7 and S7 groups). Four types of assessment were done: gross healing, mechanical strength, hydroxyproline deposition, and histopathology.
RESULTS: There were no differences between the M and S animals with respect to gross healing parameters. The mechanical strength was also not different between groups (23.8 +/- 12.7 and 24.7 +/- 9.6 mm Hg for M3 and S3, respectively; P = .863 and 91.3 +/- 65.4 and 94.8 +/- 55.9 mm Hg for M7 and S7, respectively; P = .902). Similarly, hydroxyproline deposition was not different between groups on postoperative day 3 or day 7. On postoperative day 3, the M group had significantly higher scores than the S group for fibroblast infiltration (2.4 +/- 0.7 vs 1.4 +/- 0.7, respectively; P = .008) and capillary formation (2.5 +/- 0.7 vs 0.9 +/- 0.4, respectively; P <.001). However, these effects were reversed and did not endure by day 7.
CONCLUSIONS: The study results suggest that static EMF has no effect on experimental colonic wound healing in the rat.
Int J Colorectal Dis. 2003 Mar;18(2):136-41. Epub 2002 Nov 30.
Effect of electromagnetic fields and early postoperative 5-fluorouracil on the healing of colonic anastomoses.
Nayci A, Cakmak M, Renda N, Aksoyek S, Yucesan S.
Department of Pediatric Surgery, Mersin University Medical Faculty, Mersin, Turkey. anayci@mersin.edu.tr
Abstract
BACKGROUND AND AIMS: Studies have indicated a deleterious effect of perioperative 5-fluorouracil (5-FU) administration on the healing of intestinal anastomoses. This study examined the effect of early postoperative 5-FU on the healing of colonic anastomoses and investigated the effect of electromagnetic fields (EMF) on colonic anastomotic repair under normal physiological conditions and in the presence of 5-FU therapy in a rat model.
MATERIALS AND METHODS: Forty male Wistar rats were randomly assigned into four groups and underwent a standardized left colonic resection and anastomoses. The animals then served as control or received intraperitoneal 5-FU (20 mg/kg per day, 5 days), EMF stimulation (10.76 mT, 50 Hz; 2-h on/10-h off cycles, 7 days) or both, starting on the day of surgery. After 7 days anastomotic healing was assessed by measurement of hydroxyproline content and breaking strength.
RESULTS: Hydroxyproline content increased in EMF exposed group (1.53+/-0.11 to 1.92+/-0.11 microg/mg) and in EMF + 5-FU group (1.53+/-0.11 to 1.89+/-0.12 microg/mg). Breaking strength also increased in the EMF group (0.23+/-0.02 to 0.27+/-0.01 MPa) and in the EMF + 5-FU group (0.23+/-0.02 to 0.28+/-0.01 MPa. No differences were found in hydroxyproline content or breaking strength between the 5-FU group and controls.
CONCLUSION: Early postoperative 5-FU administration did not impair the healing of colonic anastomoses in rats. Additionally, EMF stimulation provided a significant gain in colonic anastomotic strength, in rat intestines in control animals and in animals exposed to 5-FU.
Dis Colon Rectum. 2001 Aug;44(8):1181-8.
Comparison of electromagnetic field stimulation on the healing of small and large intestinal anastomoses.
Nayci A, Cakmak M, Aksoyek S, Renda N, Yucesan S.
Department of Pediatric Surgery, Mersin University Medical Faculty, PK 33070, Mersin, Turkey.
Abstract
PURPOSE: Magnetic fields have been shown to affect biologic processes. Accordingly, an experimental study was designed to investigate the effect of electromagnetic field stimulation on intestinal healing and to compare small and large intestinal anastomoses.
METHODS: An ileal or a colonic anastomosis was constructed in rats. Beginning the day after surgery, randomly assigned groups were exposed to sinusoidal electromagnetic field stimulation of 10.76-mT intensity and 50-Hz frequency, with 2-hour-on/10-hour-off cycles. After seven days, intestinal anastomoses were assessed for hydroxyproline content and breaking strength. Statistical comparison between each experimental and control group yielded significance (P < 0.05) in all cases.
RESULTS: Hydroxyproline content increased significantly in ileum from 1.650 +/- 0.11 (mean +/- standard error of the mean) to 2.036 +/- 0.11 microg/mg (P = 0.0249) and in colon from 1.526 +/- 0.11 to 1.922 +/- 0.11 microg/mg (P = 0.0135). Breaking strength also increased significantly in ileum from 0.213 +/- 0.01 to 0.255 +/- 0.01 MPa (P = 0.001) and in colon from 0.227 +/- 0.01 to 0.270 +/- 0.01 MPa (P = 0.006).
CONCLUSIONS: Electromagnetic field stimulation provided a significant gain in anastomotic healing in both small and large intestine. There were no apparent differences detected between the healing of small and large intestinal anastomoses except for slight differences in the time sequences of events and magnitude. The study demonstrated a significant increase in both biochemical and mechanical parameters. Additional investigations are needed to determine optimal conditions and promote selective biologic responses.
Dis Colon Rectum. 1996 Sep;39(9):1031-8.
Influence of pulsed electromagnetic fields on healing of experimental colonic anastomosis.
Mente? BB, Ta?cilar O, Tatlicio?lu E, Bor MV, I?man F, Türközkan N, Celebi M.
Department of Surgery, Gazi University Medical School, Ankara, Turkey.
Abstract
PURPOSE: The study investigated the influence of pulsed electromagnetic fields (PEMFs) on the mechanical strength and collagen content of uncomplicated colonic anastomosis in rats.
METHODS: A standardized left colonic resection was performed 3 cm above the peritoneal reflection, and end-to-end anastomosis was constructed with eight interrupted inverting sutures. Beginning immediately after surgery, randomly assigned groups were exposed to one of the following: 1) 100 Hz (frequency), 1 mT (intensity) PEMFs with 16-hour on/8-hour off cycles (n = 8); 2) 100 Hz, 2 mT PEMFs with 16-hour on/8-hour off cycles (n = 8); 3) 100 Hz, 1 mT PEMFs with 6-hour on/6-hour off cycles (n = 6), whereas the control group (n = 10) received no PEMFs. Relaparatomy was performed at 72 hours postoperatively, and the bursting pressure of the anastomotic segment was recorded in situ. The hydroxyproline contents of the anastomotic and adjacent perianastomotic segments of equal lengths were determined.
RESULTS: Mean bursting pressure values of the groups that received 100 Hz, 1 or 2 mT PEMFs with 16-hour on/8-hour off cycles (90.88 +/- 19.13 and 83.88 +/- 7.08 mmHg, respectively) were significantly higher than those of the control group (61.66 +/- 10.6 mmHg) and the group with 6-hour on/6-hour off cycles (64.83 +/- 7.36 mmHg; P < 0.05 for all comparisons). Hydroxyproline contents of the anastomotic and perianastomotic segments were consistently higher in the 16-hour on/8-hour off PEMF groups, compared with those of the corresponding segments of the control group.
CONCLUSIONS: PEMFs applied externally to unrestrained rats within a “window of PEMF parameters” provided a significant gain in the mechanical strength of the colonic anastomosis, at least 72 hours post-operatively. Associated relative increases in the hydroxyproline contents of the (peri)anastomotic colonic segments suggest that an altered collagen metabolism might contribute to this enhancement of the anastomotic repair. Further investigations based on these preliminary data and the definition of the exact measures regarding the effects of PEMFs on biologic systems, in general, may lead to an efficient and new adjunctive modality in colorectal surgery.
Tokai J Exp Clin Med. 1993 Jun;18(1-2):49-55.
The effect of electromagnetic field stimulation on corticosteroids-inhibited intestinal wound healing.
Dindar H, Renda N, Barlas M, Akinay A, Yazgan E, Tinçer T, Cakmak M, Konkan R, Gökçora IH, Yücesan S.
Department of Pediatric Surgery, School of Medicine, Ankara University, Türkiye.
Abstract
Electromagnetic field (EMF) stimulation has been used successfully in the clinical setting to promote healing of ununited fractures. In a few studies, EMF stimulation enhanced soft tissue healing. To investigate the effect of EMF stimulation on intestinal wound healing in normal rats and in those treated with corticosteroids, 80 Wistar rats received twice-daily injections of either saline dexamethasone (0.1 mg/kg/day for 2 weeks. Animals then underwent creation of single-layer, inverting small intestine anastomoses. All injections were continued postoperatively. Animals were grouped as intestinal anastomoses; intestinal anastomoses plus EMF stimulation; intestinal anastomoses plus dexamethasone; and intestinal anastomoses plus dexamethasone plus EMF. On postoperative days 7 and 14, the anastomosed intestines were removed and the tensile strength (TS) and hydroxyproline (OH-P) contents measured. EMF stimulation significantly increased intestinal wound healing in normal animals by the 7th and 14th day. Corticosteroids significantly impaired the healing of the small intestine anastomoses, with decreased TS and OH-P contents after the first and second weeks. However, EMF stimulation significantly reversed this inhibitory effect.