Preparation And Preliminary Study On Clinical Safety And Efficacy Of The Collagen Nerve Scaffold With Longitudinally Oriented Microchannels

Section 1 Preparation of the Collagen Nerve Scaffold with Longitudinally Oriented MicrochannelsObjective To construct the tissue engineering nerve scaffold with longitudinally oriented microchannels and prepare for the following clinical study.Methods The tissue engineering nerve scaffold with longitudinally oriented microchannels was conducted by the improved gradient freeze-drying technique,with the collagen as raw material.Its internal microstructure was observed under the scanning electron microscope(SEM).Results In this experiment,a tissue engineering nerve scaffold with longitudinally oriented microchannels was successfully prepared.Under the SEM,the longitudinal section of the scaffold was a microchannel-like structure with longitudinally parallel arrangement.The inner diameter of the microchannel was between 22 ?m and 60 ?m(mean,38.24 ± 12.31 ?m),which was relatively uniform.The cross-section of the scaffold is a honeycomb-like structure.There are lots of mutually communicating pore-like structures among the parallel microchannels.The nerve scaffold could highly simulate the normal nerve basement membrane in both material and internal structure.Conclusion The nerve scaffold prepared by the improved gradient freeze-drying technique could highly simulate the normal nerve basement membrane in both material and internal structure,and satisfy the bionics requirements of the material and structure of the nerve tissue engineering scaffold.Section 2 Preliminary Study on Clinical Safety of the Collagen Nerve Scaffold with Longitudinally Oriented MicrochannelsObjective To preliminarily evaluate the clinical safety of the collagen nerve scaffold with longitudinally oriented microchannels in repairing the peripheral nerve defects.Methods From July 2017 to March 2018,a total of 5 patients with 8 peripheral nerve defects of 18 to 30 mm(mean,23.8 mm),who met the inclusion and exclusion criteria,were involved and treated in the pilot study,including 6 digital nerves and 2medial antebrachial cutaneous nerves.The defects were repaired with the collagen nerve scaffold with longitudinally oriented microchannels independently developed by the research group.Routine therapy of prophylactic systemic antibiotics but no immunosuppressive drugs was given in all patients postoperatively.The clinical safety of the nerve scaffold was evaluated through observing the condition of the healing of the local wound and the whole body.The blood routine and biochemical indexes were texted and collected.Results All patients were followed up.No adverse events such as infection,allergy,damage of liver and kidney function occurred.The incisions healed primarily,with no redness,exudation and rupture in the local area.There was no systemic symptom such as fever,nausea,vomiting,skin itching,etc.The results of blood routine tests and biochemical tests were normal.The data of tests was not statistically significant(P>0.05).Conclusion The preliminary study shows that it is clinically safe to bridge peripheral nerve defects with the collagen nerve scaffold with longitudinally oriented microchannels.Section 3 Preliminary Study on Clinical Efficacy of the Collagen Nerve Scaffold with Longitudinally Oriented MicrochannelsObjective To preliminarily evaluate the clinical efficacy of the collagen nerve scaffold with longitudinally oriented microchannels in repairing the peripheral nerve defects.Methods From July 2017 to March 2018,5 patients with 6 digital nerve defects of 18 to 28 mm(mean,21.7 mm),who met the inclusion and exclusion criteria,were involved and treated in the pilot study.The defects were repaired with the collagen nerve scaffold with longitudinally oriented microchannels independently developed by the research group.The skin sensation of the repaired finger innervation area was examined during the follow-up after operation,such as pain,touch,and two-point discrimination,etc.The sensory assessment of the repaired digital nerve was evaluated according to the British Medical Research Council(BMRC)sensory function assessment standards(1954).Results All patients were follow-up for 6 to 14 months,with an average of 9 months.All repaired digital nerves achieved improved sensory function,of which,static two-point discrimination of 3 fingers was 4 mm,7 mm and 8 mm.According to BMRC sensory function assessment standards(1954),there was 1 finger getting assessed S4,2 S3~+ and 3S2.Conclusion The preliminary study shows that it is clinically effective to repair the peripheral nerve defects with the collagen nerve scaffold with longitudinally oriented microchannels independently developed by the research group.It could promote the regeneration of the injured peripheral nerves and the reconstruction of function.