Ultrasonographic evaluation of canine supraspinatus calcifying tendinosis.

Supraspinatus calcifying tendinosis is an uncommon finding in dogs. Although its radiographic appearance has been described previously, radiographs alone do not provide detailed information about the tendon parenchyma. Tendon ultrasonography has been widely applied for the diagnosis of human tendinosis, but it remains underused in dogs. This article reviews the ultrasonographic technique and variable appearance of canine supraspinatus calcifying tendinosis observed in 33 tendons. The ultrasonographic findings are described. The most common ultrasonographic finding was a hyperechoic area accompanied by distal acoustic shadowing. No relationship with bicipital tenosynovitis was found. A color Doppler examination was possible in only five of the tendons, revealing no blood flow in those tendons. There was evidence that the presence of a hypoechoic area surrounding the calcification was related to clinical signs of pain, suggesting an active inflammatory process. Ultrasonography was an excellent technique to evaluate lesions of the supraspinatus tendon and it revealed details not apparent on radiographs.

Effects of observer on the diagnostic accuracy of low-field MRI for detecting canine meniscal tears.

Low-field MRI (lfMRI) has become increasingly accepted as a method for diagnosing canine meniscal tears in clinical practice. However, observer effects on diagnostic accuracy have not been previously reported. In this study, 50 consecutive stifle joints with clinical and radiologic evidence of cranial cruciate ligament insufficiency were investigated by lfMRI and arthroscopy. Fifteen observers who had varying levels of experience and who were unaware of arthroscopic findings independently reviewed lfMRI studies and recorded whether lateral and medial meniscal tears were present. Diagnostic accuracy (sensitivity, specificity, positive (PPV) and negative predictive value (NPV)) was determined for each observer and median values were calculated for all observers, using arthroscopy as the reference standard. Interrater agreement was determined based on intraclass correlation coefficient (ICC) analysis. Observer level of experience was compared with diagnostic sensitivity and specificity using correlation analysis. Based on pooled data for all observers, median sensitivity, specificity, PPV, and NPV for lfMRI diagnosis of lateral meniscal tears were 0.00, 0.94, 0.05, and 0.94, respectively. Median sensitivity, specificity, PPV, and NPV for medial meniscal tears were 0.74, 0.89, 0.83, and 0.79, respectively. Interrater agreement for all menisci was fair (0.51). Menisci were less consistently scored as having no tears (ICC = 0.13) than those scored as having tears (ICC = 0.50). No significant correlations between observer experience and diagnostic sensitivity/specificity were identified. Findings indicated that the accuracy of lfMRI for diagnosing canine meniscal tears was poor to fair and observer-dependent. Future studies are needed to develop standardized and widely accepted lfMRI criteria for diagnosing meniscal tears.

MR-imaging of lumbosacral intervertebral disc degeneration in clinically sound German shepherd dogs compared to other breeds.

German shepherd dogs are overrepresented in the group of dogs with cauda equina compression syndrome due to degenerative lumbosacral stenosis. A congenital predisposition for early degeneration of the lumbosacral intervertebral disc has been suspected. Our aims were to assess the morphologic appearance of the lumbosacral intervertebral disc and the lumbosacral junction in healthy German shepherd dogs compared to other breeds and to evaluate for an early onset of degenerative changes. The lumbosacral spine of 110 clinically sound German shepherd dogs and 47 healthy dogs of other large breeds was examined using magnetic resonance (MR) imaging. The degeneration of every intervertebral disc was graded using an established classification system. Signal intensity of the entire lumbosacral disc and the nucleus pulposus was determined independently. Lumbosacral malalignment was assessed according to a previously described method. The findings for the German shepherd dogs were compared to those of the other breeds. Although most dogs were younger than 18 months at the date of examination, significantly higher grades of degeneration were detected for the lumbosacral intervertebral disc of German shepherd dogs (P < 0.003). Degeneration of the lumbosacral intervertebral disc was independent from findings in the other lumbar discs. We conclude that the German shepherd dog has a predisposition for degenerative changes in the lumbosacral intervertebral disc.

Neuroanatomy of the calf brain as revealed by high-resolution magnetic resonance imaging.

Here, we want to assess the benefit of high-resolution and high-contrast magnetic resonance imaging (MRI) for detailed documentation of internal brain morphology in formalin-fixed whole head specimens of the full-term calf brain (Bos taurus). Imaging was performed on a Siemens 1.5 T scanner. Optimum contrast was achieved using a 3D sequence with a flip angle of 30 degrees , repetition time (TR) of 20 ms, echo time (TE) of 6.8 ms, and an interpolated matrix of 1024 x 1024. In plane resolution was 0.25 mm. Computer-generated three-dimensional images were reconstructed from the original scans in the coronal plane. This study shows that MRI is capable to identify delicate structures in immature brain specimens. The use of MRI in comparative morphology facilitates the examination of series of brains or brain samples in a reasonable time. The comprehensive description of species- and group-specific brain features in MRI scans of Bos taurus will complement existing data for diagnostic imaging and neuromorphological research, in general, as well as for phylogenetic reconstructions.

Ultrasonographic appearance of the craniocervical junction in normal brachycephalic dogs and dogs with caudal occipital (Chiari-like) malformation.

Ultrasonographic evaluation of the spine, especially of the spinal cord, has been rarely reported in dogs. The atlanto-occipital junction provides a small acoustic window through which examination of the craniocervical transition can be performed. Normal sonographic findings of this region in 10 normal brachycephalic dogs are presented and compared with sonographic findings from 25 Cavalier King Charles Spaniels with the caudal occipital malformation syndrome. Sonographic findings were compared with magnetic resonance imaging findings to determine the extent of cerebellar herniation and syringohydromyelia. Cerebellar displacement into the foramen magnum was clearly identified sonographically; however, syringohydromyelia was not discernable due to bone overlay.

Influence of femoral head and neck conformation on hip dysplasia in the German Shepherd dog.

We investigated the prevalence of an anatomic variant of the proximal femur, termed the broomstick-like femoral head and neck formation, and its influence on the Féderation Cynologique Internationale (FCI) hip dysplasia score in 294 German Shepherd dogs. One-hundred and eighty (61%) of the 294 dogs in our study had this anatomic variant. The calculated area of the femoral heads in dogs with a broomstick-like conformation was 4.5 +/- 0.6 cm2 on the hip-extended view. In dogs with a normal femoral head, the calculated area of the femoral head was significantly larger at 4.8 +/- 0.6 cm2 (P < 0.05). In the frog-leg view, there was no significant difference in femoral head area between dogs with the broomstick-like conformation and normal dogs. There was no difference in the antetorsion angle between dogs with broomstick-like conformation and normal dogs. There was also no difference in the distraction ratio between the two phenotypes. The official FCI hip score was similar in dogs with and without the broomstick-like conformation. The average heritability of the broomstick-like conformation was 0.3 +/- 0.1, suggesting heritable influence. We conclude that the broomstick-like conformation is a common finding in the German shepherd dog and has genetic base. The broomstick-like conformation does not appear to be associated with the presence of canine hip dysplasia and it can therefore be assumed to be a normal anatomic variant.