Epidural fibrosis following spinal surgery is common, and subsequent reoperations are more technically challenging with higher complication rates. A safe and effective therapeutic solution to this difficult clinical problem has yet to be realized. Previous research has demonstrated the effectiveness of alanyl-glutamine in reduction of peritoneal adhesions in a rat abdominal sepsis model. I hypothesized that alanyl-glutamine may be similarly efficacious in minimizing epidural fibrosis in a rat laminectomy model. Rats were randomized into three groups: no surgery, laminectomy/normal saline and laminectomy/alanyl-glutamine (1g/kg). The surgical groups underwent a lumbar laminectomy with instillation of either normal saline or alanyl-glutamine into the peridural space. Thirty days after surgery, the rats were euthanized and the spinal columns prepared for histological evaluation. A blinded veterinary pathologist and a less experienced student independently graded the extent and maturity of epidural fibrosis. The laminectomy model was an effective model for epidural fibrosis formation. Rats that underwent laminectomy demonstrated significant fibrosis compared to control animals (p<0.001). However, there was no significant difference in histological grade of fibrosis between normal saline and alanyl-glutamine treatment groups (p=0.83). Based on this study, alanyl-glutamine does not appear to have an effect in reducing epidural fibrosis at a histological level. It is possible that alanyl-glutamine may have an effect that is not detectable using this model, in which case further studies with a more sensitive model may be indicated. Resources may be better used elucidating the mechanism by which glutamine acts to reduce adhesions in the peritoneal model and further studies exploiting those mechanisms can be designed.

Background Epidural fibrosis (EF) is defined as nonphysiological scar formation, usually at the site of neurosurgical access into the spinal canal, in intimate vicinity to and around the origin of the radicular sheath. From the very onset, EF behaves as a reparative inflammation causing, as a rule, symptoms of characteristic nature and clinical course (pain). Treatment of epidural fibrosis causing failed back surgery syndrome (FBSS) by neuromadulation technique is very expensive. Finding of suitable parameters for the indication of treatment is therefore very important. Aims The study is based on evidence of the importance of epidural fibrosis for the development of chronic pain. Research is also focused on the comparison of the range fibrosis and the effect of stimulation (spinal cord stimulation - SCS). The goal is to find a suitable selection factor for the indication of neuromodulation. Methods I. A double-blind prospective study was conducted to investigate a cohort of 200 patients requiring surgical treatment for intervertebral disc hernia (hernia disci intervertebralis). The patients were randomly and blindly divided into 2 groups, one on peroperatively applied local doses of a mixture containing corticosteroids, the other without such medication. All the requirements of a double-blind...

Background Epidural fibrosis (EF) is defined as nonphysiological scar formation, usually at the site of neurosurgical access into the spinal canal, in intimate vicinity to and around the origin of the radicular sheath. From the very onset, EF behaves as a reparative inflammation causing, as a rule, symptoms of characteristic nature and clinical course (pain). Treatment of epidural fibrosis causing failed back surgery syndrome (FBSS) by neuromadulation technique is very expensive. Finding of suitable parameters for the indication of treatment is therefore very important. Aims The study is based on evidence of the importance of epidural fibrosis for the development of chronic pain. Research is also focused on the comparison of the range fibrosis and the effect of stimulation (spinal cord stimulation - SCS). The goal is to find a suitable selection factor for the indication of neuromodulation. Methods I. A double-blind prospective study was conducted to investigate a cohort of 200 patients requiring surgical treatment for intervertebral disc hernia (hernia disci intervertebralis). The patients were randomly and blindly divided into 2 groups, one on peroperatively applied local doses of a mixture containing corticosteroids, the other without such medication. All the requirements of a double-blind...

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this experiment was to document the postoperative evolution of New Zealand rabbits that underwent a hemi laminectomy surgery (T13-L1) and received a graft of autogenous muscle as an hemostatic agent into the spinal canal. These animals were followed for a period of 14 and 28 days with daily neurological assessments and, at the end of their follow-up period, were euthanized in order to remove the graft site to be examined microscopically. The animals were divided into 6 groups such as the control group A and B, C and D treated with 25% decrease of the medullary canal and, E and F treated with 50% decrease of the medullary canal. All groups were evaluated neurologically every day until euthanasia. Groups A, C and E were euthanized at 14 days after the surgery and groups B, D and F at 28 days. The segments T11-L3 vertebral column of all the rabbits were collected and sent for histopathological examination. In order to evaluate the neurological postoperative effect, the animals were classified daily by the Tarlov scale and the results were compared by nonparametric Kruskal-Wallis test for each time (days). There was no statistical difference among the groups. Histopathological examination showed the presence of muscle grafted in the spinal canal and the spinal cord compression caused by the graft. / A hemorragia é uma preocupação importante em pacientes submetidos a intervenção cirúrgica descompressiva da medula espinhal ou de estabilização na coluna vertebral. O objetivo desse experimento foi documentar a evolução pós-operatória de coelhos Nova Zelândia que sofreram hemilaminectomia (T13-L1) e receberam um segmento de músculo autógeno como agente hemostático dentro do canal vertebral. Os animais foram separados em seis grupos sendo os grupos A e B controle, C e D tratados com diminuição de 25% do canal medular e E e F tratados com diminuição de 50% do canal medular. Todos os coelhos tiveram avaliação neurológica diária até a eutanásia. Aqueles dos grupos A, C e E sofreram eutanásia aos 14 dias de pós-operatório e os demais (B, D e E) aos 28 dias. Os segmentos T11-L3 da coluna vertebral contendo a medula espinhal de todos os coelhos foram coletados e enviados para exame histopatológico. Para avaliação neurológica no pós-operatório, os animais foram classificados diariamente pela escala de Tarlov e os resultados foram comparados entre eles pelo teste não paramétrico de Kruskal-Wallis para cada tempo (dia). Não houve diferença estatística da avaliação neurológica entre os grupos estudados. O exame histopatológico demonstrou a presença do músculo transplantado no canal vertebral e a compressão da medula espinhal provocada pelo enxerto.

Made available in DSpace on 2014-07-29T15:07:41Z (GMT). No. of bitstreams: 1 Dissertacao Ana Carolina Vasques Villela.pdf: 1200187 bytes, checksum: e80340dfd98ca2e1e517f50dcd0bef34 (MD5) Previous issue date: 2012-02-24 / A anestesia local se popularizou na medicina veterinária no século XX, mas alguns de seus recursos, como o cateter epidural e as soluções hiperbáricas, bastante utilizados no homem atualmente ainda são pouco estudados e aplicados em animais. Em seguida, outro estudo verificou a qualidade da anestesia epidural toracolombar com lidocaína a 2% ou hiperbárica a 5% e a influência do decúbito e o do tempo de permanência do cateter epidural na qualidade deste bloqueio. Para isso foram usados sete cães machos, adultos, pesando 12,76 +/-2,59 kh. Com os animais até o espaço T13-L1, tendo seu dispositivo sepultado no tecido subcutâneo. Em seguida, administrou-se 4 mg/kg de lidocaína isobárica a 2% com os animais em posição quadrupedal(IQ4) ou em decúbito lateral (IL4); 3 mg/kg de lidocaína hiperbárica a 5% em posição quadrupedal (HQ3) ou em decúbito lateral (HL3); e 4 mg/kg de lidocaína hiperbárica a 5% em posição quadupedal (HQ4) ou em decúbito lateral (HL4). Foram avaliadas a viabilidade da técnica de implantação; a ocorrência de complicações após a implantação ou retirada do cateter epidural; o tempo de permanência do cateter epidural; os efeitos da administração de lidocaína a 2% ou hiperbárica a 5% sobre a FC, , PAS, SPO2 e TR; a a qualidade do bloqueio anestésico (latência, extensão, simetria e duração do bloqueio anestésico); influência do decúbito e do tempo de permanência do cateter na qualidade do bloqueio anestésico. A implantação do cateter epidural foi viável e isenta de complicações; houve redução significativa somente nos valores de e TR em relação ao valor basal nos grupos IQ4, IL4, HQ3, HL3,HQ4. Não foram observadas diferenças significativas na FC, PAS, SPO2, latência, duração e extensão do bloqueio entre os grupos. O decúbito não influenciou significativamente a qualidade do bloqueio. O tempo de permanência do cateter no espaço epidural influenciou significativamente a duração máxima do bloqueio sensitivo. Em conclusão, o modelo descrito para implantação do cateter epidural é viável, porém o tempo que o cateter permaneceu no espaço epidural influenciou a duração do bloqueio anestésico e a lidocaína hiperbárica a 5% não mostrou vantagens em relação ao uso da lidocaína isobárica a 2% na anestesia epidural toracolombar.