【Abstract】 Objective To investigate the surgical management of dural injuries and postoperative cerebrospinal fluid(CSF) fistulas in spinal surgeries and to observe cl inical outcomes, since intraoperative injury of dura mater and postoperative CSF fistulas are common compl ications of spinal surgeries. Methods A retrospective research was designed and 405 patients with complete data who underwent spinal surgeries between June 2002 and March 2006 were acquired, including 298 cases of male and 107 cases of female, with the mean age of 46.2 years (ranging from 11 years to 78 years). The course of disease lasted from 3 months to 5 years. A total of 28 cases of intraoperative dural injuries and durotomies (28/405, 6.91%) were recorded, including 3 cases of cervical spinal surgery (3/152, 1.97%), 19 cases of thoracic and lumbar spinal surgery (19/239, 7.95%) and 6 cases of sacral surgery (6/14, 42.86%). CSF fistulas occurred in 6 cases of 28 patients. There were 2 cases in which no intraoperative dural injury was detected but CSF fistulas occurred after operation. The incidence of postoperative CSF fistula was 1.98% (8/405). Surgical management included closure of breach in the dura mater, oversewing every layer of the wound, bed rest and compression dressing and so on. Cl inical outcomes of surgical management were recorded. Results The average followup lasted for 1 year and 5 months (ranging from 3 months to 4 years). Preoperative symptoms remitted to different extents There were 8 cases of postoperative CSF fistula which were cured ultimately. A total of 6 cases of CSF fistulas from dorsal injuries of dura mater were treated mainly by bed rest, compression dressing and reoperations, while 2 cases of fistulas from ventral and lateral injuries of dura mater were treated by additional continuous cerebrospinal fluid drainage using a lumbar subarachnoid catheter. One case of central nervous system infection occurred and was treated successfully by multi-discipl inary disposal. Conclusion Timely and correct surgical intervention and postoperative management can help to heal dural injuries in spinal surgeries and can prevent occurrence of postoperative CSF fistulas.
Objective To determine the ability of the polyactic acid glue (PLA-G) in preventing epidural adhesion after laminectomy. Methods Each of the 24 randomly selected rats was done laminectomyof L2 and L5. The PLA-G, which would change from liquid to solid when meets with serum, was used in the epidural site of L5 to become a half-solid membrane(the experimental group, EG). The PLA-G was not used in the same site of L2(the control group, CG) .The gross anatomical, histological, and microscopical evaluation were made 2，4，6，8，10 and 12 weeks after operation; electron microscope observation was also made on two rats 4 weeks after operation(both EG and CG). Results Obvious epidural space was observed between dura mater and scar tissue(ST), but no cells in the epidural space were observed inEG 2 weeks after operation. Corps of the red cells between dura mater and ST and proliferation of fibroblast cell(FB) were observed in CG 2 weeks after operation. Some remaining glue shiver in the epidural space with lightly increasing fibroblast and smooth dura mater were observed in EG 4 weeks after operation. However, fragile scar conglutinated with dura mater diffusely and more FB were observed in CG. From the 6th week to the 12th week, a potential interspace between scar and dura mater was observed and PLA glue was absorbed completely in EG. However, tougher scar, which was very difficult to dissect from dura mater and surrounding tissues, was observed. According to the fibroblast ultrastructure observation, bigger nucleus and more plentiful rough endoplasmic reticulum were observed in CG. Conclusion The PLA-G can effectively reduce the epidural scar and adhesion in animal experiment.
ObjectiveTo clarify the structure and biomechanical characteristics of the dura mater of the cervical, thoracic, and lumbar segments of sheep, in order to provide a theoretical reference for the study of artificial dura mater.MethodsFive adult male white sheep were sacrificed. The dura mater of C5, T10, and L3 planes were obtained. The histological HE staining was used to observe the internal structure and the thickness of dura mater; the inner and outer surfaces morphology of the dura was observed by scanning electron microscopy (SEM); transmission electron microscopy (TEM) was used to observe the internal structure of dura mater and to measure the diameter of collagen fibers in each part of dura mater. The dura mater of C6, C7, T11, T12, L4, and L5 planes were taken for uniaxial biomechanical test, and modulus of elasticity, tensile strength, and elongation at break were measured.ResultsHE staining showed that the thickness of the cervical, thoracic, and lumbar dura mater gradually decreased, and the thickness of the dura mater was (268.19±15.91), (198.16±27.25), (103.74±21.54) μm, respectively, and the differences were significant (P<0.05). SEM observation showed that there were more collagen fibers and fewer cells on the inner surface of the dura mater, while more cells were distributed on the outer surface, and the cells on the inner and outer surface were stretched along the longitudinal axis. TEM observation showed that the collagen fibers in the dura mater were interlaced and arranged in layers. The collagen fibers in the lamina were arranged in the same direction, and the collagen fibers between the lamina were arranged vertically. The diameters of collagen fibers in the cervical, thoracic, and lumbar dura mater were (68.04±21.00), (64.54±20.64), (60.36±19.65) nm, respectively, and the differences were not significant (P>0.05). Uniaxial biomechanical tests results showed that there was no significant difference in modulus of elasticity, tensile strength, and elongation at break between the axial and transverse dura mater of the cervical dura mater (P>0.05); the axial data of thoracic and lumbar segments were significantly larger than the transverse data (P<0.05). The axial modulus of elasticity, tensile strength, and elongation at break of the dura mater of the cervical, thoracic, and lumbar dura mater were significantly different (P<0.05) from the transverse ones, and showing a decreasing trend. Among them, the ratio of axial and transverse modulus of elasticity of cervical and thoracic dura were significantly smaller than that of lumbar segment (P<0.05), and there was no significant difference between cervical segments and thoracic segments (P>0.05).ConclusionThe thickness of dura mater in sheep decreased gradually from head to tail. There are more collagen fibers and fewer cells on the inner surface of dura mater, while the outer surface of dura mater is covered by cells. The collagen fiberboard layers in the dura mater are arranged alternately, and have obvious anisotropic biomechanical characteristics, and the anisotropic biomechanical characteristics get more significant from the head to the tail.