Agreement between low-field MRI and CT for the detection of suspected intracranial lesions in dogs and cats

CT Findings and Histological Evaluation of Red Foxes (Vulpes vulpes) with Chronic Head Trauma Injury: A Retrospective Study

Large numbers of wild animals are injured every year in road traffic accidents. Scant data are available for rescued wild carnivores, in particular for red foxes. Cases of foxes with head trauma were retrospectively considered for inclusion in this study. Clinical examination, modified Glasgow coma scale (MGCS), computed tomography (CT) examination, therapy, outcome, and post mortem findings of the brain were investigated. In all foxes, cranial vaults lesion occurred in single (67%) or multiple sites (33%). Midline shift and hydrocephalus were observed in this population. The mean survival was 290 (±176) days. In our study, we performed CT scans on average 260 days after fox rescue, and we speculate that persisting clinical signs could be attributed to TBI. In our study, only two foxes were alive at the time of writing. Other foxes were euthanized due to the severity of the clinical signs. CT scans help diagnose chronic lesions and their effect on prognostic judgment for animals released to wildlife environments.

Computed tomography and magnetic resonance for the advanced imaging of the normal nasal cavity and paranasal sinuses of the koala (Phascolarctos cinereus)

The objective of this study is to describe computed tomography (CT) and magnetic resonance (MR) for the cross-sectional imaging of the normal anatomy of the nasal cavity and paranasal sinuses of the koala (Phascolarctos cinereus), to provide reference figures for gross anatomy with corresponding CT and MR images and to compare the features of the nasal cavity and paranasal sinuses of the normal koala with that reported in other domestic species. Advanced imaging can be used to aid in diagnosis, to plan surgical intervention, and to monitor therapeutic responses to diseases of the nasal passages in koalas. One clinically normal koala was anesthetized twice for the separate acquisition of dorsal CT scan images and transverse, dorsal, and sagittal MR images of its nasal cavity and paranasal sinuses. Sagittal and transverse CT planes were reformatted. Three fresh koala skulls were also transected in one of each transverse, sagittal, and dorsal planes and photographed. The CT and MR images obtained were matched with corresponding gross anatomic images and the normal bone, tissues and airway passages were identified. All anatomic structures were readily identifiable on CT, magnetic resonance imaging (MRI), and gross images. CT and MRI are both valuable diagnostic tools for imaging the nasal cavities and paranasal sinuses of koalas. Images obtained from this project can be used as baseline references for future comparison with diseased koalas to help with diagnosis, surgical intervention, and response to therapy.

Application of computed tomography for differential diagnosis of glioma stoke and simple cerebral hemorrhage

OBJECTIVE

To explore the value of computed tomography (CT) in the differential diagnosis of glioma stroke and simple cerebral hemorrhage.

MATERIALS AND METHODS

A total of 45 patients with glioma stroke and stroke as the initial symptom in our hospital from Jun., 2009 to Oct., 2013 were selected along with 50 individuals with simple cerebral hemorrhage in the same period randomly collected as a control group. The CT results in both groups were analyzed and compared.

RESULTS

In the observation group, there were 25 patients with astrocytoma (55.6%), 11 with oligodendroglioma (24.4%), 8 with ependymoma (17.2%) and 1 with glioblastoma multiforma (GBM, 2.22%). Additionally, the major CT manifestation was coexistence of hemorrhage and tumor signs. By comparison, it could be found that the proportions of patients respectively with peripheral edema and space- occupying effect in the observation group were significantly higher than in the control group (P<0.01).

CONCLUSIONS

Application of CT examination combined with medical history in patients has very important clinical value in the differential diagnosis of glioma stroke and simple cerebral hemorrhage.

Low-field MRI and multislice CT for the detection of cerebellar (foramen magnum) herniation in Cavalier King Charles Spaniels

Background

Cavalier King Charles Spaniels (CKCS) have a high prevalence of Chiari‐like malformation (CM). Herniation of the cerebellum into the foramen magnum is a key diagnostic feature for CM. Midsagittal MR images are the preferred technique for visualizing cerebellar herniation (CH).

Objective

To investigate whether CT can be used to diagnose CH.

Animals

Fifteen client‐owned CKCS dogs referred for investigation of the brain and cranial cervical spine on MRI and CT.

Methods

Two reviewers retrospectively analyzed midsagittal T1WSE and T2WSE MR images and midsagittal pre‐ and postcontrast 2D multiplanar reformatted CT images from each dog for the presence of CH. And, if present, the length (mm, CHL) of the herniation was measured. The results were analyzed statistically.

Results

There was no significant difference between the different observers and techniques for the detection of CH and measurement of CHL. Overall, the CHL was longer on the CT images.

Conclusion and Clinical Importance

Both techniques are useful for detecting CH and measuring CHL. Because CHL does not have a known direct impact on the clinical presentation of CM, CT can be used as a diagnostic tool in a routine clinical practice for CM in CKCS when MRI is not available. We emphasize that MRI is the standard screening technique in CKCS for breeding purposes to detect the presence of CM and SM and, at the current time, CT cannot replace MRI.