Retrospective study on the incidence of cats and dogs' spinal injuries by computed tomographic scan. Part II: Thoracolumbar and lumbosacral / Estudo retrospectivo sobre incidência de injúrias em coluna vertebral de cães e gatos por meio de exame tomográfico. Parte II: Toracolombar e Lombossacral

For vertebromedullary injuries, epidemiological knowledge is essential to guide the choice of the most effective diagnostic method. The objective of this retrospective study was to describe the epidemiological profile of animals and thoracolumbar and lumbosacral spine lesions diagnosed by computed tomography scan. A compilation of CT scan reports for the aforementioned regions performed in a comercial diagnostic center from 04/01/2017 to 04/30/2020, contrasted and non-contrasted, from routine, was performed in order to list the most common lesions and their locations, as well as the species, breeds and ages most affected. There were 1164 CT scans performed in the period evaluated, all of them in dogs, 57,56% (n=670) for the spine, with 89,7% reports accessed (n=601), where the regions mentioned here added up to 73,05% studies (n=439). In both regions, male French Bulldog dogs had the most injuries. For the thoracolumbar region, disk mineralization, followed by extrusion, were the most frequent injuries, while the site was T12-13 and the mean age 6,5±3,63 years old. In the lumbosacral, disk protrusion was most frequent, the most affected site was L7-S1 and age 6,65±3,79 years. It was concluded that the spine is the main target of CT scans, and that lesions related to the intervertebral disk were the main ones identified, with chondrodystrophic animals being more predisposed to injury.

Para lesões vertebromedulares é indispensável o conhecimento epidemiológico para direcionar a escolha do método diagnóstico mais eficaz. O objetivo desse estudo retrospectivo foi descrever o perfil epidemiológico dos animais e das lesões em coluna vertebral toracolombar e lombossacral diagnosticadas através de exame tomográfico. Realizou-se a compilação de laudos de tomografias computadorizadas para as referidas regiões realizadas em centro diagnóstico comercial, entre 01/04/2017 a 30/04/2020, contrastadas e não-contrastadas, provenientes da rotina, a fim de relacionar as lesões e seus locais de ocorrência, bem como a espécie, raças e idades mais comuns. Foram realizados 1164 exames tomográficos no período avaliado, sendo 57,56% (n=670) para a coluna, com 89,7% laudos acessados (n=601), nos quais as regiões toracolombar e lombossacral somaram 73,05% dos estudos (n=439). Em ambas as regiões, os cães Bulldog Francês machos foram os que mais apresentaram lesões. Para a região toracolombar, a mineralização de disco, seguida pela extrusão, foram as lesões mais frequentes, enquanto o local foi T12-13 e a média de idade 6,5±3,63 anos. Na lombossacral, a protusão de disco foi mais frequente, o local mais afetado foi L7-S1 e idade de 6,65±3,79 anos. Concluiu-se que a coluna vertebral é o principal alvo de tomografias, e que as lesões relacionadas ao disco intervertebral foram as principais identificadas, sendo os animais condrodistróficos mais predispostos a lesões.

ANÁLISE POR RESSONÂNCIA MAGNÉTICA E HISTOGRAMA EM ESCALA DE CINZA DAS AFECÇÕES DISCAIS EM CÃES DA RAÇA TECKEL

A doença do disco intervertebral (DDIV) envolve degeneração discal (metaplasias condroide e fibroide), extrusão (Hansen tipo I), protusão (Hansen tipo II) e extrusão discal aguda não compressiva, com variada intensidade de lesão medular. Cães da raça Teckel apresentam maior risco de DDIV relacionado com outras raças. A ressonância magnética (RM) é o método de eleição para a avaliação das enfermidades do disco intervertebral, pois as características do sinal do disco na RM refletem suas alterações. O histograma em escala de cinza (HEC) é uma técnica de imagem, que permite avaliar a quantidade e distribuição dos tons de cinza na imagem de RM. O objetivo desse estudo visou classificar quantitativamente as doenças do disco intervertebral (DDIVs) pelo HEC em imagens de RM. Foram avaliados 51 exames de RM, em cães da raça Teckel, realizados em aparelho de RM Esaote® Vet MR Grande, 0,25 Tesla. A sequências de pulso utilizadas foram a FSE T2 nos planos transversal, sagital e dorsal (TS FSE T2, SAG FSE T2 e DORS FSE T2). As imagens de RM da coluna vertebral dos cães da raça teckel foram analisadas em três grupos: Filhotes, adultos e idosos. O HEC foi realizado nos DIVs selecionados aleatoriamente entre os indivíduos, e classificados como discos hidratados, degenerados, protruídos e extruídos. Observou-se predominância de extrusão discal em 45,10% dos animais. Na análise do HEC não houve diferença significativa para essas afecções, obtendo uma média das médias (mediamean) de 43,4 para discos degenerados, 45,1 para Hansen tipo I, 45,2 para Hansen tipo II. Entretanto foi significativo para diferenciação dos discos alterados em comparação com os discos hidratados que obtiveram um valor de 67,0. A RM possibilitou a identificação e incidência das DDIV´s e o HEC apresentou especificidade significativa na avaliação quantitativa discal, sendo possível indicar um disco degenerado precocemente.

Intervertebral disc disease (IVDD) involves disc degeneration (chondroid and fibroid metaplasia), extrusion (Hansen type I), protrusion (Hansen type II) and non-compressive acute disc extrusion with varying degree of spinal cord injury. Teckel dogs are at increased risk of IVDD in relation to other breeds. Magnetic resonance imaging (MRI) is the method of choice for the evaluation of intervertebral disc diseases, since the characteristics of the disc signal in MRI reflect its changes. The grayscale histogram (GSH) is a technique that allows to evaluate the amount and distribution of grayscale in the IVD in the MRI.The purpose of this study was to quantitatively classify the IVDD by GSH in MRI images.51 MR examinations were performed in dogs of the Teckel breed, performed on an Esaote ® Vet - MR Large, 0.25 Tesla. The pulse sequences used were the ESF T2 in the transverse, sagittal and dorsal planes (TS FSE T2, SAG FSE T2 and DORS FSE T2). The MR images of the vertebral column of dogs of the teckel breed were analyzed in three groups: Puppies, adults and elderlies. The GSH was performed on the IVD randomly selected among the individuals, and classified as hydrated, degenerated, protruded and extruded discs. A predominance of disc extrusion was observed in 45.10% of the animals. In the GSH analysis, there was no significant difference for these affections, obtaining a mean (mediamean) mean of 43.4 for degenerate discs, 45.1 for Hansen type I, 45.2 for Hansen type II. However, it was significant for differentiation of the altered disc compared to the hydrated disc that obtained a value of 67.0. MRI allowed the identification and incidence of IVDD and GSH showed significant specificity in the quantitative disc evaluation, being possible to indicate an early degenerated disc.

Ascending hemorrhagic myelomalacia secondary to intervertebral disc protrusion in a dog / Mielomalácia hemorrágica ascendente secundária à protrusão de disco intervertebral em cão

Background: Myelomalacia is a multifocal syndrome that causes hemorrhagic infarction of the spinal cord that can occur as a sequel to acute spinal cord injury. It occurs as a consequence of acute spinal cord trauma, usually by extrusion of intervertebral disc in the thoracolumbar spine, affecting up to 10% of dogs with acute paralysis and deep pain loss in the pelvic limbs due to disc disease. This disease may be focal or diffuse; the diffuse form is typically associated with cranial and caudal migration of neurologic signs and is often fatal. The mechanical lesion to the spinal cord triggers secondary injury mediated by the existence of oxygen free radicals, alterations in the concentrations of neurotransmitters ions and amino acids, and it results in the reduction of the spinal cord blood fl ow, ischemia and progressive cranial and caudal necrosis to the focus of the initial injury.Case: A 5-year-old Dachshund male intact dog weighting 8 kg was referred to the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (HCV-UFRGS) with initial complaint of acute paralysis of the hind limbs for two days. On clinical examination there was paraplegia, absence of deep pain in the pelvic limbs, with decreased patellar, sciatic and tibial cranial refl exes. The anal sphincter was relaxed and the bladder was easily expressed. The panniculus refl ex was intact up to t

Background: Myelomalacia is a multifocal syndrome that causes hemorrhagic infarction of the spinal cord that can occur as a sequel to acute spinal cord injury. It occurs as a consequence of acute spinal cord trauma, usually by extrusion of intervertebral disc in the thoracolumbar spine, affecting up to 10% of dogs with acute paralysis and deep pain loss in the pelvic limbs due to disc disease. This disease may be focal or diffuse; the diffuse form is typically associated with cranial and caudal migration of neurologic signs and is often fatal. The mechanical lesion to the spinal cord triggers secondary injury mediated by the existence of oxygen free radicals, alterations in the concentrations of neurotransmitters ions and amino acids, and it results in the reduction of the spinal cord blood fl ow, ischemia and progressive cranial and caudal necrosis to the focus of the initial injury.Case: A 5-year-old Dachshund male intact dog weighting 8 kg was referred to the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (HCV-UFRGS) with initial complaint of acute paralysis of the hind limbs for two days. On clinical examination there was paraplegia, absence of deep pain in the pelvic limbs, with decreased patellar, sciatic and tibial cranial refl exes. The anal sphincter was relaxed and the bladder was easily expressed. The panniculus refl ex was intact up to t

Mielomalácia hemorrágica ascendente secundária à protrusão de disco intervertebral em cão / Ascending Hemorrhagic Myelomalacia Secondary to Intervertebral Disc Protrusion in a Dog

Background: Myelomalacia is a multifocal syndrome that causes hemorrhagic infarction of the spinal cord that can occur as a sequel to acute spinal cord injury. It occurs as a consequence of acute spinal cord trauma, usually by extrusion of intervertebral disc in the thoracolumbar spine, affecting up to 10% of dogs with acute paralysis and deep pain loss in the pelvic limbs due to disc disease. This disease may be focal or diffuse; the diffuse form is typically associated with cranial and caudal migration of neurologic signs and is often fatal. The mechanical lesion to the spinal cord triggers secondary injury mediated by the existence of oxygen free radicals, alterations in the concentrations of neurotransmitters ions and amino acids, and it results in the reduction of the spinal cord blood flow, ischemia and progressive cranial and caudal necrosis to the focus of the initial injury. Case: A 5-year-old Dachshund male intact dog weighting 8 kg was referred to the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (HCV-UFRGS) with initial complaint of acute paralysis of the hind limbs for two days. On clinical examination there was paraplegia, absence of deep pain in the pelvic limbs, with decreased patellar, sciatic and tibial cranial reflexes. The anal sphincter was relaxed and the bladder was easily expressed. The panniculus reflex was intact up to the 10th thoracic vertebra (T10). The patient had exacerbated pain on palpation of the thoracic spine. The other physiological parameters were within normal limits. Based on clinical findings, ascending myelomalacia was the presumed diagnosis. Biochemical and haematological profiles were unremarkable. The myelographic examination did not reveal a site of spinal cord compression, as the column of contrast suffered no deviation or blockage in its path. Pain was medically managed. The following day, the animal had hypothermia, forelimbs paresis, dyspnea and abdominal breathing. The panniculus reflex had migrated cranially, to the height of the 6th thoracic vertebra (T6). The owner opted for euthanasia and the patient was referred to necropsy. At necropsy the L1-L2 intervertebral disc suffered disc protrusion and not extrusion. Along the spinal cord there was multifocal hemorrhage in the white and gray matter, with gliosis, malacia, fibrin deposition and axonal spheroids. In the lumbar spinal segments L1 and L2, there was neutrophilic infiltrate and calcification area in the meninges. Discussion: It is often cited in the literature that young dogs, especially the Dachshund breed, are prone to intervertebral disc disease, with acute paralysis and, in severe cases, myelomalacia ascending, as in this case. What is rare, though, is the occurrence of myelomalacia associated with disc protrusion only instead of disc extrusion. The multifocal character of the disease evidenced by changes and worsening of neurological signs in the course of the disease was reported in this case. The physical examination findings and its evolution are the same cited in the literature, such as atonic bladder, absence of patellar reflex, anal sphincter relaxation. Dyspnea is related to paralysis of the intercostal muscles and diaphragm and is irreversible and fatal. Early diagnosis of myelomalacia ascending hemorrhagic myelomalacia is crucial to prevent death from respiratory failure due to the progression of the disease. Effective treatment for preventing the progression of necrosis and hemorrhage resulting from spinal thoraco-lumbar disc disease, acute paraplegia and which leads to loss of deep pain has not been found yet.

Mielografia e ressonância magnética no diagnóstico da doença do disco intervertebral em cães: revisão de literatura / Diagnosis of intervertebral disc disease in dogs mielography and magnetic resonance: literature review

A mielografia e a ressonância magnética são modalidades de imagem aplicadas como recurso no diagnóstico da doença interveterbral. A mielografia é o exame de eleição no diagnóstico definitivo da doença do disco intervertebral na medicina veterinária, com alto grau de precisão na localização da lesão. Esse exame além de localizar com maior precisão o foco da extrusão ou protusão, permite a avaliação da presença e do grau de lesão medular.O objetivo deste trabalho é descrever os achados de imagem da mielografia e da ressonância magnética em pacientes com doença do disco intervertebral, comparado as informações obtidas e abordando os pontos favoráveis e desfavoráveis desses métodos de diagnóstico por imagem nessa enfermidade(AU)

The mielography and magnetic ressonance are modalities of image applied as a resource in the diagnosis of intervertebral disease. The miolography is the most recommended exam to define the intervertebral disc disease in veterinary medicine, high precision to locate the lesion. It can situate with high accuaracy the extrusion or protusion focus and allows evaluating the presence and the degree of intramedulary spinal cordal damage.The objective of this article is to describe the image signs of mielography and magnetic resonance in patients presenting the intervertebral disc diasease comparing the information, including the favorable and disfavorable points of these two kinds of image diagnosis in that illness(AU)

Mielografia e ressonância magnética no diagnóstico da doença do disco intervertebral em cães: revisão de literatura / Diagnosis of intervertebral disc disease in dogs mielography and magnetic resonance: literature review

A mielografia e a ressonância magnética são modalidades de imagem aplicadas como recurso no diagnóstico da doença interveterbral. A mielografia é o exame de eleição no diagnóstico definitivo da doença do disco intervertebral na medicina veterinária, com alto grau de precisão na localização da lesão. Esse exame além de localizar com maior precisão o foco da extrusão ou protusão, permite a avaliação da presença e do grau de lesão medular.O objetivo deste trabalho é descrever os achados de imagem da mielografia e da ressonância magnética em pacientes com doença do disco intervertebral, comparado as informações obtidas e abordando os pontos favoráveis e desfavoráveis desses métodos de diagnóstico por imagem nessa enfermidade

The mielography and magnetic ressonance are modalities of image applied as a resource in the diagnosis of intervertebral disease. The miolography is the most recommended exam to define the intervertebral disc disease in veterinary medicine, high precision to locate the lesion. It can situate with high accuaracy the extrusion or protusion focus and allows evaluating the presence and the degree of intramedulary spinal cordal damage.The objective of this article is to describe the image signs of mielography and magnetic resonance in patients presenting the intervertebral disc diasease comparing the information, including the favorable and disfavorable points of these two kinds of image diagnosis in that illness

Ascending hemorrhagic myelomalacia secondary to intervertebral disc protrusion in a dog / Mielomalácia hemorrágica ascendente secundária à protrusão de disco intervertebral em cão

Background: Myelomalacia is a multifocal syndrome that causes hemorrhagic infarction of the spinal cord that can occur as a sequel to acute spinal cord injury. It occurs as a consequence of acute spinal cord trauma, usually by extrusion of intervertebral disc in the thoracolumbar spine, affecting up to 10% of dogs with acute paralysis and deep pain loss in the pelvic limbs due to disc disease. This disease may be focal or diffuse; the diffuse form is typically associated with cranial and caudal migration of neurologic signs and is often fatal. The mechanical lesion to the spinal cord triggers secondary injury mediated by the existence of oxygen free radicals, alterations in the concentrations of neurotransmitters ions and amino acids, and it results in the reduction of the spinal cord blood fl ow, ischemia and progressive cranial and caudal necrosis to the focus of the initial injury.Case: A 5-year-old Dachshund male intact dog weighting 8 kg was referred to the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (HCV-UFRGS) with initial complaint of acute paralysis of the hind limbs for two days. On clinical examination there was paraplegia, absence of deep pain in the pelvic limbs, with decreased patellar, sciatic and tibial cranial refl exes. The anal sphincter was relaxed and the bladder was easily expressed. The panniculus refl ex was intact up to t

Background: Myelomalacia is a multifocal syndrome that causes hemorrhagic infarction of the spinal cord that can occur as a sequel to acute spinal cord injury. It occurs as a consequence of acute spinal cord trauma, usually by extrusion of intervertebral disc in the thoracolumbar spine, affecting up to 10% of dogs with acute paralysis and deep pain loss in the pelvic limbs due to disc disease. This disease may be focal or diffuse; the diffuse form is typically associated with cranial and caudal migration of neurologic signs and is often fatal. The mechanical lesion to the spinal cord triggers secondary injury mediated by the existence of oxygen free radicals, alterations in the concentrations of neurotransmitters ions and amino acids, and it results in the reduction of the spinal cord blood fl ow, ischemia and progressive cranial and caudal necrosis to the focus of the initial injury.Case: A 5-year-old Dachshund male intact dog weighting 8 kg was referred to the Veterinary Teaching Hospital of the Federal University of Rio Grande do Sul (HCV-UFRGS) with initial complaint of acute paralysis of the hind limbs for two days. On clinical examination there was paraplegia, absence of deep pain in the pelvic limbs, with decreased patellar, sciatic and tibial cranial refl exes. The anal sphincter was relaxed and the bladder was easily expressed. The panniculus refl ex was intact up to t

Retrospective study on the incidence of spinal injuries by computed tomographic scan. Part II: Thoracolumbar and lumbosacral

For vertebromedullary injuries, epidemiological knowledge is essential to guide the choice of the most effective diagnostic method. The objective of this retrospective study is to trace the epidemiological profile of thoracolumbar and lumbosacral spine lesions diagnosed by computed tomography scan. A compilation of CT scan reports for the aforementioned regions performed in a comercial diagnostic center from 04/01/2017 to 04/30/2020, contrasted and non-contrasted, from routine, was performed in order to list the most common lesions, breeds and locations. There were 1164 CT scans performed in the period evaluated, 670 (57,56%) for the spine, with 601 reports accessed (89,7%), where the regions mentioned here added up to 439 studies (73,05%). In both regions, male French Bulldog dogs had the most injuries. For the thoracolumbar region, disk mineralization, followed by extrusion, were the most frequent injuries, while the site was T12-13 and the mean age 6,5±3,63 years old. In the lumbosacral, disk protrusion was most frequent, the most affected site was L7-S1 and age 6,65±3,79 years. It was concluded that the spine is the main target of CT scans, and that lesions related to the intervertebral disk were the main ones identified, with chondrodystrophic animals being more predisposed to injury.

Para lesões vertebromedulares é indispensável o conhecimento epidemiológico para direcionar a escolha do método diagnóstico mais eficaz. O objetivo desse estudo retrospectivo é traçar o perfil epidemiológico das lesões em coluna vertebral toracolombar e lombossacral diagnosticadas através de exame tomográfico. Realizou-se a compilação de laudos de tomografias computadorizadas para as referidas regiões realizadas em centro diagnóstico comercial, entre 01/04/2017 a 30/04/2020, contrastadas e não-contrastadas, provenientes da rotina, a fim de relacionar as lesões, raças e locais mais comuns. Foram realizados 1164 exames tomográficos no período avaliado, sendo 670 (57,56%) para a coluna, com 601 laudos acessados (89,7%), onde as regiões aqui referidas somaram 439 estudos (73,05%). Em ambas as regiões, os cães Bulldog Francês machos foram os que mais apresentaram lesões. Para a região toracolombar, a mineralização de disco, seguida pela extrusão, foram as lesões mais frequentes, enquanto o local foi T12-13 e a média de idade 6,5±3,63 anos. Na lombossacral, a protusão de disco foi mais frequente, o local mais afetado foi L7-S1 e idade de 6,65±3,79 anos. Concluiu-se que a coluna vertebral é o principal alvo de tomografias, e que as lesões relacionadas ao disco intervertebral foram as principais identificadas, sendo os animais condrodistróficos mais predispostos a lesões.