Orthopaedic Division, Shiraz University of Medical Sciences, Shiraz, Iran. Jaberi@yahoo.com
The concept of end-to-side nerve repair was recently introduced; however, most authors have reported conflicting results with this technique. This study was conducted to assess the effectiveness of end-to-side nerve repair in both fresh and predegenerated specimens by histological evaluation in an animal study in rabbits. Thirty male rabbits were divided into three groups. In group 1 (n = 14), the peroneal nerve was divided and sutured end-to-side to the tibial nerve via an epineurial window. In group 2 (n = 13), the peroneal nerve was divided and sutured end-to-side to the tibial nerve after a 1-week "predegeneration period." In group 3 (n = 3), which was considered the control group, the peroneal nerve was divided and sutured to the adjacent soft tissues. After 3 months, specimens were harvested for histological evaluation. Nerve fiber count, in normal peroneal nerves, averaged 532/cross section. In groups 1 and 2, average nerve fiber count in implanted peroneal nerves was 6.24 and 7.00/cross section, respectively. No significant statistical difference was observed between fresh and "predegenerated" groups (P = 0.90). These data suggest that collateral sprouting of donor nerves is possible after end-to-side neurorrhaphy through an epineurial window, but the number of nerve fibers in recipient nerves is too low to result in any functional recovery in the target organ.
Discipline of Plastic Surgery at Botucatu School of Medicine, State University of São Paulo, Botucatu, São Paulo, Brazil. email@example.com
To the present day, nerve injuries still represent a challenge to the surgeon. With all the advances in microneural surgery, additional approaches need to be studied to improve functional results. End-to-side nerve repair is the newest tool in managing certain nerve injuries, especially where the surgeon is faced with long nerve gaps, when it becomes impractical to use nerve grafts. The use of long nerve grafts is associated with intraneural fibrosis and atrophy of the end organs because of the prolonged time of regrowth of axons. The authors present a full review of the history, experimental work, and clinical applications of end-to-side neurorrhaphy, such as facial palsy, brachial plexus repair, and solitary sensory nerve repair. After reading this article, the surgeon will be familiar with this newest technique available to the microneural surgeon and the situations where the technique can be used to yield good results. She or he will also be able to expand on the existing experimental work in the pursuit of best functional outcomes.
Promotion of nerve regeneration in peripheral nerve by short-course FK506 after end-to-side neurorrhaphy.
Department of Orthopedics, Peking University Third Hospital, Beijing, China.
BACKGROUND/AIMS To discuss the feasibility of peripheral nerve injury treated by end-to-side neurorrhaphy in clinic and to evaluate the effect of short-course FK506 on promoting nerve regeneration after end-to-side neurorrhaphy. METHODS Thirty adult male Sprague Dawley rats were randomly divided into 3 groups: Group A, 10 rats received end-to-end anastomosis; Group B, 10 rats received end-to-side neurorrhaphy; Group C, 10 rats received the same operation as Group B. After operation, rats in Groups B and C received muscle injection with saline water (1 mg/kg x d(-1)) and FK506 (1 mg/kg x d(-1)), respectively, both for 4 wk. Histological and morphological examinations were performed 12 wk after the operation. In the 2nd, 4th, 6th, 8th, and 12th wk after operation, function recovery analysis was performed. RESULTS The results of histological and immunochemistry study (the total number of Schwann cells and the axon numbers at the distal stump of the peroneal nerve, wet weight of extensor digitorum longus muscle) suggested that there were significant differences between Group B (saline water group) and Group C (FK506 group)(P < 0.05), also between Group A (end-to-end group) and Group C (P < 0.05). There were statistically significant differences in function recovery (peroneal functional index and sciatic functional index) between Groups B and C (P < 0.05) and also between Groups A and C (P < 0.05). CONCLUSION End-to-side repair combined with FK506 has a potential for application in selected cases of peripheral nerve injury in clinic.
Millesi Center, Vienna Private Clinic, Pelikangasse 15, A-1090 Vienna, Austria. firstname.lastname@example.org
To bring some light into the ongoing controversy concerning end-to-side coaptation in brachial plexus surgery, the authors organized a symposium in 2006 titled How To Improve Peripheral Nerve Surgery. The authors sought the participation of experienced surgeons and researchers who had made personal contributions to the field. This article contains information collected at this symposium and presents the authors' clinical results and ideas illustrating the potential of nerve fiber transfer by end-to-side coaptation.
Institute of Neurosurgery, Catholic University School of Medicine, Rome, Italy. email@example.com
End-to-side neurorrhaphy (ESN) or terminolateral neurorraphy consists of connecting the distal stump of a transected nerve, named the recipient nerve, to the side of an intact adjacent nerve, named the donor nerve,"in which only an epineurial window is performed". This procedure was reintroduced in 1994 by Viterbo, who presented a report on an experimental study in rats. Several experimental and clinical studies followed this report with various and sometimes conflicting results. In this paper we present a review of the pertinent literature. Our personal experience using a sort of end-to-side nerve anastomosis, in which the donor nerve is partially transected, is also presented and compared with ESN as defined above. When the proximal nerve stump of a transected nerve is not available, ESN, which is claimed to permit anatomic and functional preservation of the donor nerve, seems an attractive technique, though yet not proven to be effective. Deliberate axotomy of the donor nerve yields results that are proportional to the entity of axotomy, but such technique, though resembling ESN, is an end-to-end neurorrhaphy. Neither experimental or clinical evidence support liberalizing the clinical use of ESN, a procedure with only an epineurial window in the donor nerve and without deliberate axotomy. Much more experimental investigation needs to be done to explain the ability of normal, intact nerves to sprout laterally. Such procedure appears justified only in an investigational setting.
Microsurgery. 2006 ;26 (4):268-72 16628740
Phrenic nerve neurotization of the musculocutaneous nerve with end-to-side neurorrhaphy: a short report in a rabbit model.
Anna Stamatoukou, Ellada Papadogeorgou, Zijie Zhang, Kitty Pavlakis, Aristides B Zoubos, Panayotis N Soucacos
Department of Orthopedic Surgery, School of Medicine, University of Athens, Athens, Greece.
This experimental study was performed to evaluate the efficacy of end-to-side coaptation between the musculocutaneous nerve and the phrenic nerve for brachial plexus injuries with nerve-root avulsions. In an experimental rabbit model, neurotization of the musculocutaneous nerve with the phrenic nerve was compared using end-to-end and end-to-side neurorrhaphy. Preliminary results from electrophysiologic and histologic examinations indicate that end-to-side neurotization of the musculocutaneous nerve with the phrenic nerve is an effective means for musculocutaneous nerve repair. The effectiveness of the phrenic nerve is attributed to its large number of motor axons.
Ken Matsuda, Masao Kakibuchi, Kenji Fukuda, Tateki Kubo, Thomas Madura, Ken-ichiro Kawai, Kenji Yano, Ko Hosokawa
Department of Plastic Surgery, Osaka University School of Medicine, Nishinomiya, Hyogo, Japan.
The effectiveness of the end-to-side nerve graft in comparison with the end-to-end cable-graft was determined in rat sciatic nerve transection models. Sixty Sprague-Dawley rats were randomly divided into four groups with different reconstructive methods for two branches of the sciatic nerve: Group I, median nerve graft with end-to-side neurorrhaphy; Group II, median and ulnar nerve grafts with end-to-end neurorrhaphy; Group III, no repair; and Group IV, sham operation. Between Groups I and II, there were no significant differences in the functional, electrophysiologic, and histologic evaluations. In retrograde tracing of the spinal cord and dorsal root ganglia, the number of double-labeled neurons was significantly higher in Group I. End-to-side nerve grafts show good functional recovery, require less graft, and are easy to perform. The authors find this method to be an effective alternative in facial nerve reconstruction and of great value in various kinds of peripheral nerve surgery.
Nerve regeneration through a healthy nerve trunk: a new and hopeful conduit for bridging nerve defects.
Department of Plastic and Reconstructive Surgery, Gülhane Military Medical Academy, Haydarpasa Hospital, Istanbul, Turkey.
BACKGROUND: Considering a healthy nerve trunk as the hypothetically ideal conduit, a new experimental model using an intact nerve for bridging a nerve defect was contemplated. METHODS: Thirty rats were used. In group I (double coaptation), a segment was removed from the peroneal nerve. Both the proximal and distal stumps were repaired end-to-side to the tibial nerve. In group II (only distal coaptation), only the distal nerve stump was repaired. In group III (control), the transected segment was immediately repaired primarily in its original orientation as a nerve graft. A walking track analysis was conducted periodically for 28 months. The horseradish peroxidase retrograde labeling technique was used for tracking the origin of the axons presented in the distal stump of the peroneal nerve in group I, and morphologic studies were also carried out for all the groups. RESULTS: Functional assessment revealed that the difference between group I and group II was significant. The horseradish peroxidase labeling test suggested that the nerve fibers in the distal stump of the peroneal nerve were mostly from its original proximal stump passed by the way of the tibial nerve bridge. CONCLUSION: This study suggested that the axons of the proximal stump of a sectioned nerve can sprout into another intact nerve trunk by the way of an end-to-side repair site, regenerate, and advance in its epineurium distally for a distance and pass into its original distal stump if it was repaired end-to-side. It was thought that the technique could be used in clinical cases with short nerve defects as an alternative method to grafts and conduits.
Functional remobilization evaluation of the paralyzed vocal cord by end-to-side neurorrhaphy in rats.
Department of Otorhinolaryngology, Eye and ENT Hospital of Fudan University,#83 Fenyang Road, Shanghai City 200031, PR China.
OBJECTIVE To investigate the value of end-to-side neurorrhaphy to treat vocal cord paralysis. STUDY DESIGN A prospective study evaluating the effects of end-to-side neurorrhaphy to treat vocal cord paralysis by means of fiberoptic laryngoscopy and nerve electromyography. METHODS Thirty Sprague-Dawley rats were divided into experimental group 1, experimental group 2, and a control group randomly. Right recurrent laryngeal nerve (RLN) was incised, and the distal end of the RLN was anastomosed to the right phrenic nerve by end-to-side neurorrhaphy in experimental group 1 or by end-to-end nerve anastomosis in experimental group 2, respectively. The adductor nerve branch of the right RLN was incised and anastomosed to the proximal end of the right ansa cervicalis nerve by end-to-end nerve anastomosis. Fiberoptic laryngoscopy and nerve electromyography were used to examine the vocal cord movement and nerve regeneration. RESULTS Three months after operation, this effect of end-to-side neurorrhaphy created a significant difference compared with the end-to-end nerve anastomosis (P <.05). The end-to-side neurorrhaphy did not lead to vocal cord movement compared with end-to-end nerve anastomosis. CONCLUSION Vocal cord paralysis cannot be treated by this microsurgical technique.
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Oleuropein prevents ethanol-induced gastric ulcers via elevation of antioxidant enzyme activities in rats.
Masoud Alirezaei, Omid Dezfoulian, Shima Neamati, Marzyeh Rashidipour, Nader Tanideh, Arash Kheradmand
Division of Biochemistry, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad, Iran. Alirezaei_m54@yahoo.com
Purified oleuropein from olive leaf extract has been shown to have antioxidant effects in our recent studies. Thus, the aim of this study was to assess the antioxidant abilities of oleuropein in comparison with ranitidine in ethanol-induced gastric damages via evaluation of ulcer index inhibition, antioxidant enzyme activities, and lipid peroxidation level. Fifty-six adult male Sprague-Dawley rats were divided into seven equal groups as follows: control group, ethanol group (absolute ethanol 1 ml/rat), oleuropein group (12 mg/kg), and oleuropein (6, 12, and 18 mg/kg) plus ethanol groups, as well as ranitidine (50 mg/kg) plus ethanol group. Pretreatment with oleuropein (12 and 18 mg/kg) significantly increased the ulcer index inhibition (percent), in comparison with oleuropein (6 mg/kg). Glutathione peroxidase (GPx) activity was significantly lower in the ethanol group when compared with the other groups whereas, treatment of rats with oleuropein (12 mg/kg) significantly increased glutathione content in gastric tissue when compared with the other groups, and lipid peroxidation was significantly reduced in the oleuropein-(12 and 18 mg/kg) and ranitidine-treated animals. Superoxide dismutase (SOD) and catalase (CAT) activities were both much higher in oleuropein-treated rats than the ethanol group, and although there was a moderate increase in SOD and CAT activities in ranitidine-treated rats, the differences were not significant. These findings suggest that oleuropein has beneficial antioxidant properties against ethanol-induced gastric damages in the rat. Therefore, it seems that a combination regimen including both antioxidant and antisecretory drugs may be beneficial in prevention of ethanol-mediated gastric mucosal damages.
Cornea. 2012 May ;31 (5):559-63 22333665
Alireza Ghaffarieh, Fariborz Ghaffarpasand, Maryam Dehghankhalili, Nazafarin Honarpisheh, Samira Nirumandi, Nader Tanideh
Dr Khodadoust Eye Hospital, Shiraz, Fars, Iran. firstname.lastname@example.org
PURPOSE To evaluate the effect of transcutaneous application of electrical stimulation on the rate of corneal epithelial healing in corneal abrasion using an in vivo model of corneal wound healing in the rabbit. METHODS This was an experimental study including 16 adult Dutch rabbits that were randomly allocated to 2 study groups (8 in each group) to receive transcutaneous electrostimulation or no treatment. The corneal epithelium was lifted from the round limbal border. The rabbits in the study group received transcutaneous electrostimulation for 30 minutes by placing the active electrode (-) on the upper right lid and the passive electrode (+) on the right foot. Photographs of corneal epithelial defects were taken each day until the sixth day by digital photographs and the images were analyzed using software. RESULTS The healing percentage was significantly higher in those who received transcutaneous electrostimulation at days 2 (P < 0.001), 3 (P < 0.001), 4 (P = 0.001), and 6 (P = 0.014) after the procedure. The healing rate was also significantly higher in the transcutaneous electrostimulation group at days 2 (P < 0.001), 5 (P = 0.022), and 6 (P = 0.044) after the procedure. The healing rate did not differ significantly between the groups at days 3 (P = 0.169) and 4 (P = 0.426). The maximum healing rate was observed in the first 24 hours, and the minimum healing rate was observed during day 3 in the electrical stimulation group. CONCLUSIONS The transcutaneous application of electrical stimulation can considerably increase the rate of corneal healing, especially in the first 24 hours of healing full surface corneal abrasion.
Mohammad Jafar Emami, Hamid Namazi, Amir Reza Vosoughi, Simin Torabi Nezhad, Ahmad Oryan, Kamran Mozaffarian
Fereidoon M Jaberi, Sara Keshtgar, Alireza Tavakkoli, Ehsan Pishva, Bita Geramizadeh, Nader Tanideh, Mehrad M Jaberi
Bone & Joint Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
BACKGROUND AND AIMS Electromagnetic fields have been proposed to enhance healing of cartilage defects by stimulation of chondrocyte proliferation, proteoglycan synthesis as well as decreasing pain and improving motion in osteoarthritic patients. However, the effects of a moderate-intensity static magnetic field on cartilage repair have not been investigated. This study tries to determine the effects of a moderate-intensity permanent magnetic field of 40 mT on cartilage repair. METHODS Defects of 3 mm in diameter and 6 mm in depth were made on the weight bearing surface of the right medial femoral condyle of 30 rabbits. The animals were divided randomly into three equal groups (magnet, sham and control). In the magnet group, cylindrical permanent magnets were implanted subcutaneously medial to the medial femoral condyle, while in the sham group the cylindrical ceramic were not magnetized, and nothing was implanted in controls. After 12 weeks of observation, Mankin's microscopic scoring was done on all specimens, and irregularity of surface characteristics, cell colonization, hypocellularity, cartilage matrix formation, and presence of empty lacunae were investigated. RESULTS Each of these characteristics showed significant differences in magnet group relative to control and sham groups (p <0.05). Mankin's score was 1.6 ± 0.6 in magnet group, 7.2 ± 1.6 in sham group and 7.7 ± 1 in control group (p <0.001). CONLUSIONS: In this animal study, microscopic Mankin's scoring depicted histological improvement in cartilage of magnet group.
J Cardiothorac Surg. 2009 ;4 :23 19508714
Department of Surgery, New York Hospital Queens, Weill College of Cornell University, New York, USA. email@example.com
BACKGROUND Tracheal defects may occur after trauma or prolonged intubation. Resection of tracheal tumors also poses a major challenge for substitution. In an effort to solve this problem, different techniques have been tried with little success. We report on a new animal model which showed acceptable results with fewer complications. METHODS We replaced 5 cm of cervical trachea in 10 dogs with harvested infra-renal aorta and repaired the aortic defect with Dacron graft. RESULTS Necropsy of the grafted aorta and anastomotic site revealed well healed anastomosis in all animals together with ciliated columnar epithelium coverage of grafted aorta and neovascularization of aortic wall. CONCLUSION Aortic graft is preferable to other substitutes because of less antigenicity, less vascularity, and no mucous secretions or peristalsis.
J Invest Surg. ;22 (3):183-7 19466655
Evaluation of different chemical agents on the germinative layer of sheep hydatid cyst after implantation to peritoneal cavity of BALB/c.
Soheil Mansourian, Seyed Mahmoud Sadjjadi, Seyed Vahid Hosseini, Zahra Barzin, Davood Mehrabani, Nader Tanideh, Ali Rafati
Department of Surgery, Gastroenterohepatology Research Center, Nemazee Hospital, Shiraz, Iran.
In spite of the use of protoscolocidal agents during hydatid cyst surgery, a notable rate of disease recurrence in postoperation patients is still observed. The question remains whether living protoscolices lead to recurrence or the recurrence is due to the remainder of the germinative layer in the peritoneal cavity. The aim of this study was in vivo evaluation of different chemical (protoscolicidal) solutions on the germinative layer of the hydatid cyst. The germinative layer of sheep hydatid cyst was separated under sterile condition, divided into 0.25-cm(2) parts, and exposed to 0.5% cetrimide, 0.5% silver nitrate, 20% hypertonic saline, 15% dextrose and 25% dextrose, and normal saline as negative control for 2 min. The exposed germinative layers were implanted into the peritoneal cavity of 90 Balb/C mice (15 mice in each group). After nine months, the peritoneum was evaluated macroscopically as well as microscopically for the presence of any hydatid cyst. No hydatid cyst was observed in the peritoneal cavity of the exposed mice. The role of the germinative layer for inducing hydatid cysts in mice is questionable. However, the present study showed that the germinative layer had no role in the induction of hydatid cyst in these laboratory animals.
Davood Mehrabani, Aminallah Rezaee, Negar Azarpira, Mohammad R Fattahi, Masoud Amini, Nader Tanideh, Mohammad R Panjehshahin, Mehdi Saberi-Firouzi
Department of Pathology, Gastroenterohepathology Research Center, Nemazee Hospital, PO Box 71345-1744, Shiraz University of Medical Sciences, Shiraz, Iran. firstname.lastname@example.org
OBJECTIVE To determine the healing effect of Teucrium polium (T. polium) in indomethacin-induced gastric ulcer in rats. METHODS In the fall of 2007, 250 Sprague-Dawley rats provided by the Shiraz University Laboratory Animal Center were divided into 4 equal groups including control (70 rats), and 3 experimental groups (60 rats each), and each group received different doses of T. polium. Ten rats were used to study the induction of gastric ulcer by indomethacin (25 mg/kg/stat). After 24 hours, their stomachs were evaluated for any mucosal ulcer. The T. polium extract was administered orally, 24 hours after indomethacin administration. In the experimental group, 10 animals were sacrificed after 24, 48, and 72 hours, after administration of T. polium, and at one, 2, and 4 weeks, and in the control group identically after the administration of distilled water. RESULTS In rats treated with indomethacin, multiple ulcers were evident. After 4 weeks of treatment with T. polium, more re-epithelialization, proliferation, mucosal hyperplasia, migration of the gastric epithelial cells, and decrease in inflammatory cells were observed. The T. polium reduced the ulcer indices by >50% after one week,>80% after 2 weeks, and >90% after 4 weeks. CONCLUSION The healing effect of T. polium may be due to antioxidant activity along with the ability to modulate the mucin secretion, prostaglandin synthesis, and epidermal growth factor receptor expression. These results along with the non-toxicity properties of T. polium suggests it as a promising anti-ulcer compound.
J Surg Res. 2008 Nov ;150 (1):74-7 18316095
Hossein Hodjati, Kourosh Kazemi, Hamed Jalaeian, Hamid Reza Sharifzad, Naghmeh Roshan, Nader Tanideh
Department of Surgery, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran. email@example.com
BACKGROUND The problem of how to treat large tracheal lesions remains a challenge in surgery. To reconstruct a long tracheal defect, a safe method other than end-to-end anastomosis is necessary. MATERIALS AND METHODS In 14 adult cross-breed dogs, a segment of trachea including seven tracheal rings was dissected and resected circumferentially. A submuscular tunnel was induced between mucosal and muscular layers of the adjacent esophagus lying right next to the trachea. An endotracheal tube was inserted between the tracheal rings 2 and 3. Then it was passed cautiously through the esophageal submuscular tunnel and through the distal tracheal segment. The proximal and distal ends of the esophageal tunnel and trachea were approximated and anastamosed. The animals were extubated 10 days after the operation. RESULTS All dogs tolerated the surgical procedure well. The first two dogs experienced postoperative fever, tracheoesophageal fistula, aspiration pneumonia, and sepsis so hard bony components were omitted from diet. All survived animals were eating and barking well. The submuscular esophageal tunnel was patent in all animals. The new lumen was supported externally with fibrous connective tissue. The tunnelized area was covered completely with pseudostratified ciliated epithelium. CONCLUSION Due to formation of fibrous tissue between skeletal muscular structures of the neck and the external layer of the tunnelized esophagus, the new airway remained patent. Overall, air tightness, good reepithelialization, and relatively no limitation of esophageal length are the advantages of tracheal reconstruction by submuscular esophageal tunneling. This new method is worthy of further investigation, as it is technically feasible and easy to implement.
Correlation of clinical and pathological findings in patients with lupus nephritis: a five-year experience in Iran.
Shiraz Nephrology Center, Shiraz Medical School, Shiraz, Iran. firstname.lastname@example.org
Lupus nephritis (LN) is the most common and serious manifestation of systemic lupus erythematousus (SLE). The World Health Organization (WHO) and International Society of Nephrology/Renal Pathology Society (ISN/RPS 2003) classifications tend to correlate with the clinical syndrome and provide valuable information regarding prognosis and guideline for treatment. We retrospectively studied patients with biopsy proven lupus nephritis at our center from 1999 - 2003 to find whether clinical and laboratory parameters used to evaluate how close the diagnosis correlated with WHO and/ or ISN/RPS 2003 classification. There were 144 patients of whom 84.7 % were females with a mean age of 25.6 +/- 10.3 years at the time of renal biopsy. The most frequent SLE presenting features were arthralgia, edema and hypertension. WHO class IV and ISN/RPS class IV were compatible with these most frequent SLE presenting features in 56% and 54.9% of the cases, respectively. Edema, hypertension, increased BUN and Creatinine, increased 24 hours urine protein excretion and decreased serum albumin level were related with a worse class of lupus nephritis. We conclude that there is a correlation between some clinical and laboratory findings, and histopathological lupus classification on renal biopsy ,which remains indispensable in the management of lupus nephritis.
Mehdi Salehipour, Abdolaziz Khezri, Ahmad Monabbati, Hamed Jalaeian, Mohsen Kroup, Valiallah Azizi, Nader Tanideh
Division of Urology, Department of Surgery, Shiraz University of Medical Sciences, Shiraz, Iran. E-Mail email@example.com
OBJECTIVE To evaluate the effects of unilateral ischemic insult and ischemic preconditioning (IPC) on renal histology in a canine model. METHODS 30 dogs were randomized into 4 groups. In group A (5 male controls) and group B (5 female controls), ischemia was induced by clamping both left renal arteries for 40 min. Dogs in group C (10 male cases) or group D (10 female cases) underwent 5 min of arterial clamping and 10 min of declamping prior to the final 40-min ischemia induction. Renal biopsy was prepared 48 h later and microscopically examined. RESULTS The control groups (A and B) developed 40% frank necrosis, 60% moderate injury, and there was no intact renal tissue in this group with no difference between sexes. The IPC groups (C and D) revealed 55% moderate injury and 45% normal pathology; however, there was no frank necrosis among them. Better IPC protection in the female group was not statistically significant. CONCLUSION An IPC schedule of 5-min ischemia and 10-min reperfusion improves ischemia-reperfusion injury from subsequent prolonged ischemia in a canine model.
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J Neurotrauma. 2012 Aug 8;: 22873667
INFLUENCE OF BREACHING THE CONNECTIVE SHEATHS OF THE DONOR NERVE ON ITS MYELINATED SENSORY AXONS AND ON THEIR SPROUTING INTO THE END-TO-SIDE COAPTED NERVE IN THE RAT.
Faculty of Medicine, University of Ljubljana, Institute of Pathophysiology, Zaloska cesta 4, Ljubljana, Slovenia, 1000; firstname.lastname@example.org.
Influence of breaching the connective sheaths of the donor sural nerve on axonal sprouting into the end-to-side coapted peroneal nerve was examined in the rat. In parallel, the effect of these procedures on the donor nerve was assessed. The sheaths of the donor nerve at the coaptation site were either left completely intact (group A) or they were breached by epineurial sutures (group B), an epineurial window (group C) or a perineurial window (group D). In group A, the compound action potential (CAP) of sensory axons was detected in about 10% and 40% of the recipient nerves at 4 and 8 weeks, respectively, which was significantly less frequently than in group D at both recovery periods. In addition, the number of myelinated axons in the recipient nerve was significantly larger in group D than in other groups at 4 weeks. At 8 weeks, the number of axons in group A was only about 15% of the axon numbers in other groups (p < 0.05). Focal subepineurial degenerative changes in the donor nerves were only seen after 4 weeks, but not later. The average CAP area and the total number of myelinated axons in the donor nerves were not different among the experimental groups. In conclusion, myelinated sensory axons are able to penetrate epi-perineurium of donor nerve after end-to-side nerve coaption; however, their ingrowth into recipient nerve is significantly enhanced by breaching the epi-perineurial sheets at the coaptation site. Breaching does not cause permanent injury to the donor nerve.
Plastic Surgery Division, Botucatu School of Medicine, UNESP, Brazil. email@example.com
PURPOSE Compare two new methods with the traditional end-to-side neurorrhaphy. METHODS Rats were divided into four groups. In A-L group the peroneal nerve was sectioned and the distal stump was connected to the lateral of the tibial nerve (donor) with two 10-0 nylon points. In A-R group two perineurium flaps embraced the donor nerve. In the B-R group a suture embraced the donor nerve. Group B-L was the control. After six months tibial cranial muscle mass and morphometry of the distal stump of the peroneal nerve were evaluated. RESULTS Muscle mass in groups A-R, A-L and B-R were lower than B-L group (p<0.0001) an equal between themselves (p>0.05). Groups A-R, B-R and A-L had a lower number of nerve fibers when compared with B-L (p=0.0155, p=0.016, p=0.0021). CONCLUSION The three types of neurorrhaphy showed no differences related to muscle mass and number of nerve fibers suggesting that the embracing with a single suture has great potential due its simplicity and usefulness in deep areas.
Comparison of nerve content in removed parametrial tissue after classic radical hysterectomy and nerve-sparing radical hysterectomy--histologic evaluation.
Department of Obstetrics and Gynecology, University Medical Centre Ljubljana, Ljubljana, Slovenia. firstname.lastname@example.org
PURPOSE OF INVESTIGATION The aim of this study was to find whether nerve-sparing radical hysterectomy resulted in a lower amount of nerves in the removed parametrial tissue. METHODS Histological specimens from nerve-sparing radical hysterectomy (28 cases) were compared with those obtained after classic radical hysterectomy (26 cases). Width of the parametria and vaginal cuff were measured. Using a point counting technique, nerve areal density was determined in cross sections of resected parametria at 0.5 cm (A), 1 cm (B), 1.5 cm (C) from the cervix. RESULTS The width of the resected parametria was smaller in the study group (right side p < 0.013; left side; p < 0.011). The nerve areal density in the lateral part of the right parametrium was lower in the study group (p < 0.01)(Student's t-test). CCONCLUSION: Modified radical hysterectomy is less radical and is nerve-sparing.
Functional motor nerve regeneration without motor-sensory specificity following end-to-side neurorrhaphy: an experimental study.
Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical College, Zhejiang, China.
PURPOSE To evaluate the quality of regenerating myelinated axons and motor-sensory specificity in an end-to-side nerve repair model. METHODS We divided 20 rats into 3 groups:(1) end-to-side neurorrhaphy using the ulnar nerve as donor nerve and the musculocutaneous nerve as recipient nerve;(2) normal control; and (3) transected nerve with the stumps buried. At 5 months, we monitored the grooming test, the electrophysiological response, and the histologic changes in nerve and muscle. RESULTS Grooming recovered successfully, and electrophysiological investigations revealed that the target muscles had been reinnervated in the end-to-side group. The mean wet weight of the reinnervated biceps brachii muscle was 72% of the normal muscle, and the mean muscle fiber cross-sectional area of the reinnervated muscle was similar to the normal muscle. The implanted musculocutaneous nerve contained varying but satisfactory numbers of axons (end-to-side group: 596 ± 348 vs normal group: 1,340 ± 241). Acetylcholinesterase staining revealed a similar percentage of myelinated fibers in the musculocutaneous nerve (39%) and the biceps brachii branch of the musculocutaneous nerve (38%) in the end-to-side group. This was similar to the number of myelinated fibers in the donor ulnar nerve (37%). CONCLUSIONS The present study confirms that limited but functional reinnervation can occur on the basis of collateral sprouting of intact axons from the ulnar nerve. The motor-sensory specificity is not important.
Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
To observe the histological alterations of single nerve fiber structures after nerve elongation by employing a rabbit peroneal nerve stretching model. 14 rabbits weighing mean 3. 0 kg (2.02-3.31 kg.) were used in the experiment. Two rabbits were used as control when only a sham operation was done (group one, 0% stretch). Acute stretching of the peroneal nerves to elongate them by 10% was done in 6 rabbits (group two, 10% elongation) and by 20%(group three, 20% elongation) in another 6 rabbits. All animals were evaluated by tissue staining technology in a teased-fiber study. The internodal lengths were measured, and nodes of Ranvier and Schmidt-Lanterman notch were observed. The nerve fiber length was increased after stretching. The mean internodal length was 1208.31 microm in group one, 1347.26 microm in group two, and 1411.35 microm in group three. Compared with the control group, mean internodal length was elongated by 11.50% in group two and 16.80% in group three. The difference was statistically significant. The node of Ranvier and Schmidt-Lanterman notch was wider in both group two and group three. Rupture of nerve fiber at the node of Ranvier was observed in group three. The peroneal nerve in rabbits can adapt to mild stretching by internodal length elongation. Elongation by 20% will cause structural rupture and therefore is the limit for nerve elongation.
Nerve Repair by End-to-Side Nerve Coaptation: Histologic and Morphometric Evaluation of Axonal Origin in a Rat Sciatic Nerve Model.
Hannover Medical School, Institute of Neuroanatomy and Center for Systems Neuroscience, Hannover, Germany (Haastert)(Grothe) Hannover Medical School, Institute of Neuroanatomy, Hannover, Germany (Joswig)(Jäschke) International Neuroscience Institute, Hannover, Germany (Samii).
OBJECTIVE: We compared the origin and quality of regenerating myelinated axons after end-to-side neurorrhaphy or end-to-end neurorrhaphy. METHODS: Transected adult rat tibial nerves were either end-to-end coapted or the distal stump was sutured to a perineurial window of the fibular nerve. Electromyographic recordings from the gastrocnemius muscle 8 weeks later revealed reinnervation by tibial nerve axons. Retrograde tracing of neurons projecting across the coaptation sites was performed with DiI for the tibial nerve and FluoroGold for the fibular nerve to reveal the origin of regenerating axons. Orientation of regenerating axons was demonstrated by immunohistochemical staining of the coaptation sites. Nerve cross-sections proximal and distal to the coaptation sites were evaluated regarding quality and quantity of myelinated axons inside the donor and acceptor nerves in comparison to nonoperated nerve samples. RESULTS: Compound muscle action potential responses were not different 8 weeks after end-to-side as compared with end-to-end coaptation. Double fluorescence of spinal motoneurons (L4-L6) and dorsal root ganglion neurons (L4-L6) elucidated events of collateral sprouting of sensory and motor donor axons. Morphometric analysis demonstrated significantly higher numbers of regenerated myelinated axons distal to end-to-end as distal to end-to-side repair. Furthermore, events of axonal sprouting in the donor nerve proximal to the end-to-side coaptation site were discovered. However, with quantitative parameters such as fiber density and g-ratio, no impairment of the donor nerve was evident. CONCLUSION: The current study supports the hypothesis that end-to-side neurorrhaphy represents an opportunity for peripheral nerve repair when a proximal nerve stump is not available.
Department of Orthopedic Surgery, Yeson Hospital, Bucheon, Korea.
BACKGROUND The aim of this study was to evaluate the contribution of the proximal nerve stump, in end-to-side nerve repair, to functional recovery, by modifying the classic end-to-side neurorrhaphy and suturing the proximal nerve stump to a donor nerve in a rat model of a severed median nerve. METHODS Three experimental groups were studied: a modified end-to-side neurorrhaphy with suturing of the proximal nerve stump (double end-to-side neurorrhaphy, Group I), a classic end-to-side neurorrhaphy (Group II) and a control group without neurorrhaphy (Group III). Twenty weeks after surgery, grasping testing, muscle contractility testing, and histological studies were performed. RESULTS The grasping strength, muscle contraction force and nerve fiber count were significantly higher in group I than in group II, and there was no evidence of nerve recovery in group III. CONCLUSIONS The contribution from the proximal nerve stump in double end-to-side nerve repair might improve axonal sprouting from the donor nerve and help achieve a better functional recovery in an end-to-side coaptation model.
Int Rev Neurobiol. 2009 ;87 :251-68 19682641
Department of Hand Surgery, Evgenidio Hospital, Athens, Greece.
End-to-side (ETS) nerve repair is used in selected clinical cases. The mechanisms, by which regeneration into the attached nerve segment is initiated and occur, are still not fully understood. Based on numerous experimental studies, different mechanisms have been suggested by which regenerating axons are recruited, such as contamination from the proximal nerve segment, collateral sprouting, and terminal regenerating sprouting from the donor nerve. A variety of experimental models, most commonly in the lower and upper extremity of rats, and techniques have been used to shed light on the mechanisms. Retrograde labeling techniques have revealed that collateral sprouting do occur, but is probably, at least as observed in long-term experiments, less important over time. Pruning of branching nerve fibers, induced by the collateral sprouting, is an additional mechanism in this context. Experiments have also focused on the stimuli, including the question of epineurial or perineurial windows, that trigger the sprouting of axons form the donor nerve, which can detected by the use of markers of cellular injury. In the present article, we review studies contributing to clarifications of mechanisms of end-to-side nerve repair, including used experimental techniques. We also stress the importance of the plastic brain.
J Anat. 2009 Nov ;215 (5):506-21 19682138
Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan.
Proximal nerve injury often requires nerve transfer to restore function. Here we evaluated the efficacy of end-to-end and end-to-side neurorrhaphy of rat musculocutaneous nerve, the recipient, to ulnar nerve, the donor. The donor was transected for end-to-end, while an epineurial window was exposed for end-to-side neurorrhaphy. Retrograde tracing showed that 70% donor motor and sensory neurons grew into the recipient 3 months following end-to-end neurorrhaphy compared to 40-50% at 6 months following end-to-side neurorrhaphy. In end-to-end neurorrhaphy, regenerating axons appeared as thick fibers which regained diameters comparable to those of controls in 3-4 months. However, end-to-side neurorrhaphy induced slow sprouting fibers of mostly thin collaterals that barely approached control diameters by 6 months. The motor end plates regained their control density at 4 months following end-to-end but remained low 6 months following end-to-side neurorrhaphy. The short-latency compound muscle action potential, typical of that of control, was readily restored following end-to-end neurorrhaphy. End-to-side neurorrhaphy had low amplitude and wide-ranging latency at 4 months and failed to regain control sizes by 6 months. Grooming test recovered successfully at 3 and 6 months following end-to-end and end-to-side neurorrhaphy, respectively, suggesting that powerful muscle was not required. In short, both neurorrhaphies resulted in functional recovery but end-to-end neurorrhaphy was quicker and better, albeit at the expense of donor function. End-to-side neurorrhaphy supplemented with factors to overcome the slow collateral sprouting and weak motor recovery may warrant further exploration.
Department of Orthopaedic Surgery, Patan Hospital, Lalitpur, Lagankhel, Lalitpur, Nepal.
OBJECTIVE To analyze the influence of muscle tension in the histological changes of the skeletal muscle. METHODS Fifty-four Sprague-Dawley (SD) rats were randomly divided into 3 groups. The left gastrocnemius muscles of the rats were dissected with only the neurovascular pedicles intact; the tibial nerves were cut and immediately repaired by epineurial suture. Then the Achilles tendons were isolated and treated accordingly; the Achilles tendon were lengthened by 0.5 cm in lengthened group, shortened by 0.5 cm in shortened group and left alone in normal (control) group. In the 2nd, 4th and 8th weeks after operation, the specimens were taken from gastrocnemius muscle for histological study by light and electron microscope. RESULTS In comparison between the groups, the gastrocnemius muscles in the shortened group showed less severe muscle atrophy and connective tissue proliferation, bigger diameter and cross section area of the muscle fibre than those in the normal and lengthened groups in all the postoperative periods. CONCLUSION A proper high tension of the muscle may decrease the muscle dystrophy and stops the histological changes of skeletal muscle by having much longer fibre length and bigger cross sectional area. Also increases the muscle function as the muscle active force-generating range is determined by muscle fibre length, while maximum muscle force is determined by physiologic cross-sectional area.