Computed tomography angiography, sonography, scintigraphy, and portography can be used to evaluate the portal vasculature to evaluate for a portosystemic shunt (PSS). Time-of-flight magnetic resonance angiography (TOF-MRA) and contrast-enhanced MRA (CE-MRA) are other potentially useful techniques. The aim of this study was to evaluate CE-MRA in 10 dogs suspected of having a PSS. Noncontrast MR images of the abdomen were obtained using a Siemens Symphony MR-scanner (1.5 T) and a T1-weighted FLASH-3D sequence with a very short scan time (about 20 s). After injection of contrast medium, the initial sequence was repeated five times. The sequence with the best contrast medium filling of the portal vasculature was selected subjectively, subtracted from the initial survey image series, and a maximum intensity projection (MIP) of the subtraction data, in multiple views, was created. The cross-sectional and MIP images were evaluated for abnormal portosystemic vasculature. A single PSS was identified and confirmed at surgery in all dogs. A portocaval shunt was found in five dogs, a portophrenic shunt in three dogs, a portoazygos shunt in one, and a central divisional intrahepatic shunt in one other dog. Based on our results, CE-MRA is a useful tool for imaging abdominal and portal vasculature and for the diagnosis of a PSS. r

A 17 mo old female Jack Russell terrier was diagnosed with unilateral primary malignant nephroblastoma. The dog presented with polyuria and polydipsia. Laboratory tests revealed polycythemia and elevated serum erythropoietin levels. Diagnostic imaging (i.e., MRI) revealed a unilateral renal mass without spinal cord involvement. Nephrectomy was performed, and the histopathologic diagnosis was nephroblastoma. The dog did not receive any chemotherapy, and there was no evidence of recurrent disease or metastasis over 30 mo after nephrectomy. This is the first case report of a dog presenting with polyuria and polydipsia found to be a result of nephroblastoma. Furthermore, this is the longest survival reported for canine nephroblastoma treated with nephrectomy alone.

BackgroundLeukoencephalomyelopathy is an inherited neurodegenerative disorder that affects the white matter of the spinal cord and brain and is known to occur in the Rottweiler breed. Due to the lack of a genetic test for this disorder, post mortem neuropathological examinations are required to confirm the diagnosis. Leukoencephalopathy with brain stem and spinal cord involvement and elevated lactate levels is a rare, autosomal recessive disorder in humans that was recently described to have clinical features and magnetic resonance imaging (MRI) findings that are similar to the histopathologic lesions that define leukoencephalomyelopathy in Rottweilers. Leukoencephalopathy with brain stem and spinal cord involvement is caused by mutations in the DARS2 gene, which encodes a mitochondrial aspartyl-tRNA synthetase. The objective of this case report is to present the results of MRI and candidate gene analysis of a case of Rottweiler leukoencephalomyelopathy to investigate the hypothesis that leukoencephalomyelopathy in Rottweilers could serve as an animal model of human leukoencephalopathy with brain stem and spinal cord involvement.Case presentationA two-and-a-half-year-old male purebred Rottweiler was evaluated for generalised progressive ataxia with hypermetria that was most evident in the thoracic limbs. MRI (T2-weighted) demonstrated well-circumscribed hyperintense signals within both lateral funiculi that extended from the level of the first to the sixth cervical vertebral body. A neurodegenerative disorder was suspected based on the progressive clinical course and MRI findings, and Rottweiler leukoencephalomyelopathy was subsequently confirmed via histopathology. The DARS2 gene was investigated as a causative candidate, but a sequence analysis failed to identify any disease-associated variants in the DNA sequence.ConclusionIt was concluded that MRI may aid in the pre-mortem diagnosis of suspected cases of leukoencephalomyelopathy. Genes other than DARS2 may be involved in Rottweiler leukoencephalomyelopathy and may also be relevant in human leukoencephalopathy with brain stem and spinal cord involvement.

SummaryA 16-year-old Warmblood gelding was presented with head tilt and a history of increasing numbers of seizures with alterations in consciousness. After each seizure the horse was depressed and quiet whereas before the episodes the gelding was restless, distracted and showed signs of discomfort (chewing, rolling its eyes). In the interictal period the horse was normal. Magnetic resonance imaging revealed a third ventricle mass and ventriculomegaly of the third and lateral ventricles. Histology of the mass was consistent with a well differentiated ependymoma. Keywords Signalment, History, Clinical findingsA 16-year-old warmblood gelding was presented with a 1-year history of progressive changes in mentation and recurrent paroxysmal collapse since 4 weeks. On clinical examination vital parameters were within physiological range (heart rate 40/min, respiratory rate 16/min). Superficial abrasions were evident on the horses` hind limbs. On neurological examination, the gelding was depressed. The horse showed a normal gait while it revealed slight proprioceptive deficits and delayed limb placement correction. Cutaneus trunci reflex and slap test were normal. The horse displayed a mild head tilt to the left with absence of pathological nystagmus. Evaluation of the cranial nerves bilaterally revealed mid-sized nonresponsive pupils. Hence, pupillary light reflex could not be elicited while vision was not impaired. Tongue tone and cervical reflexes were physiological. Examination of tail carriage, anal tone and anal reflex revealed no abnormalities. An intracranial disease was suspected with involvement of the midbrain and reticular activating system. Laboratory examination of blood revealed no abnormal findings. As the owner wanted the diagnostics and treatment to be cost restrictive an attempt was made to rule out infectious or inflammatory conditions by administering drugs. The horse showed no improvement upon treatment with systemic antibiotics, steroids and non-steroidal antiinflammatory drugs. The owner finally elected euthanasia and consented to extended postmortem examinations. ImagingA post-mortem Magnetic Resonance Imaging (MRI) of the neurocranium was performed immediately after euthanasia and cervical transection. All scans were performed with a 1.5 Tesla magnet (Magnetom Symphony, Siemens Medizintechnik, Erlangen, Germany) equipped with a spine coil and CP body array flex coil. The head and cervical spine were placed in left lateral recumbency. Images of the head and brain were acquired with T2-weighted turbo spin-echo (T2W) sequences in sagittal, dorsal and transverse planes (TR 8810 msec; TE 105). A T1-weighted 3D gradient-echo (T1W) sequence with multiplanar reconstruction images in sagittal orientation was acquired (TR 350; TE 17). Scans were accomplished by additional Fluid Attenuated Inversion Recovery (FLAIR; TR 9130; TE 127; TI 2500) and a T2*-weighted gradient echo sequence (T2*W; TR 1000; TE 28) in transverse plane. Dorsal, transverse and sagittal images of the cranial cervical spine (C1-C4) we...

A 6-week-old female Simmental calf was evaluated for acute non-ambulatory tetraparesis. Physical and laboratory examinations revealed no clinically relevant abnormalities. Neurological findings were consistent with acute, progressive and painful cervical myelopathy. Radiographs displayed a fractured odontoid process (dens axis) and vertebral step misalignment at the fracture site. A traumatic origin was suspected. Advanced diagnostic imaging was considered to allow better planning of potential surgical stabilisation and to exclude any additional lesions of the cervical vertebral column. However, during trailer transportation to the advanced diagnostic imaging and surgery site, the calf deteriorated neurologically and was humanely euthanised. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed immediately post-mortem for scientific reasons. The MRI examination reflected the radiographic findings and confirmed severe spinal cord compression at the fracture site. In addition, a T2W-hyperintense signal change within the paravertebral soft tissue dorsal to the fracture site was indicative of a traumatic event. CT identified the fracture site at the synchondrosis between the odontoid process and the body of the axis, and this finding was confirmed by post-mortem examination. Advanced diagnostic imaging and post-mortem examination did not identify any other cervical lesion. In summary, this calf was diagnosed with a traumatic odontoid process synchondrosis fracture, which has not been reported previously in calves but presents a challenging and well-known fracture type in young children. This case report indicates that the odontoid process synchondrosis is a potential predisposed injury site and that traumatic odontoid process synchondrosis fractures should be considered as a potential differential in calves with acute cervical pain and/or signs of a cervical myelopathy.

Zusammenfassung:In einer retrospektiven Analyse der MRT-Untersuchungen von Hundeund Katzenpatienten der Chirurgischen und Gynäkologischen Kleintierklinik der LMU München wurde nach Patienten gesucht, bei denen MR-Signalveränderungen im Muskelparenchym oder in Sehnen chirurgisch, zytologisch oder histopathologisch bestätigt werden konnten. Die Untersuchungen wurden hinsichtlich Untersuchungstechnik sowie MR-Erscheinungsbild verschiedener Erkrankungen und traumatischer Veränderungen des Muskelund Sehnengewebes evaluiert. Fettsupprimierende und flüssigkeitssensitive Sequenzen sowie T1-gewichtete Bilder mit Fettsuppression nach Kontrastmittelgabe sind für die Interpretation des Muskelund Sehnengewebes besonders hilfreich. Neben den Folgen schwerer Muskelund Sehnentraumata, die mit morphologischen Architekturveränderungen einhergehen, lassen sich MR-Signalveränderungen des Muskelparenchyms ohne Zusammenhangstrennungen in drei Gruppen einteilen. Veränderungen mit Muskelödem, z. B. als Folge geringgradiger Traumata oder bei Myositiden, zeigen in flüssigkeitssensitiven Sequenzen eine diffuse Signalsteigerung, während in T1-gewichteten Sequenzen Signalveränderungen fehlen. Hochgradige Muskelatrophien mit diffuser Fettinfiltration weisen als Charakteristikum eine generalisierte Signalanhebung in der Muskulatur in T1und T2-gewichteten Sequenzen auf. Davon abzugrenzen sind raumfordernde Strukturen wie intramuskuläre Hämatome, Abszesse oder Neoplasien, die die normale Architektur und Textur des Muskelparenchyms verändern und unterschiedliche Signalcharakteristika aufweisen können. Da sich die MR-Erscheinungsbilder einzelner Erkrankungen in einer Gruppe stark überschneiden können, ist eine definitive Diagnose anhand der MR-Signalveränderungen allein oft nicht zu stellen. Zusammen mit Anamnese und klinischen Befunden ergibt sich aber meist eine Verdachtsdiagnose. Ferner können die Veränderungen mit der MRT klar lokalisiert und Ausdehnung sowie Grad visualisiert werden, was eine gezielte Biopsie und dadurch eine histologische Diagnose ermöglicht.

Objective: To characterize the clinical presentation, advanced imaging features, and outcome of orbital disease in a referral population of dogs and cats that underwent computed tomography (CT) or magnetic resonance imaging (MRI).Animals studied: Client-owned animals.Procedures: Animals referred for orbital disease undergoing ophthalmic examination and either head MRI or CT were included. Demographic and imaging features were compared between animals diagnosed with inflammatory disease and neoplastic disease using Mann-Whitney U and Fischer's exact tests.Results: Ninety-seven animals (81 dogs and 16 cats) were included. Eighty-four and 13 patients underwent CT and MRI scanning, respectively. Inflammatory orbital disease was more frequently detected than neoplasia in dogs (59% vs. 41%) and cats (62% vs. 39%). Orbital cellulitis was the most common diagnosis in dogs (36/81, 44.4%) and cats (8/16, 80%). A foreign body was suspected in 36.1% of dogs with orbital cellulitis but only 3 were retrieved during orbitotomy. Multi-drug resistant bacteria were identified in 3 samples and influenced treatment plans. The most common neoplasms were sarcoma (10/30) and carcinoma (7/30) in dogs and lymphoma in cats (3/6). Imaging findings of osteolysis (p = 0.0002) and intracranial extension (p = 0.0001) were significantly associated with neoplasia in dogs. In contrast, osteolysis extension was present in cats with both inflammatory (7/10) and neoplastic (6/6) orbital disease.Conclusions: Inflammatory disease, particularly orbital cellulitis, was more common than neoplasia in dogs and cats with orbital disease in our population.We recommend including bacterial culture and susceptibility as part of the diagnostic work up when orbital cellulitis is suspected.

Durch die weiterentwikkelte Technik ist es möglich, jedem Patienten die Untersuchungsergebnisse in elektronischer Form auszuhändigen. Dem überweisenden Tierarzt wird damit ein wichtiges Hilfsmittel für die Operationsplanung und Behandlung zur Verfügung gestellt. Allerdings ist meist nur der Spezialist in der Lage, sich anatomisch schnell und sicher zu orientieren. Anatomische Beschreibungen des Kopfbereiches des Pferdes im MRT existieren nur im englischsprachigen Schrifttum (Arenciba et al. 2000,2001, Chaffin et al. 1997). Ziel dieser Arbeit war eine kurze anatomische Übersicht klinisch wichtiger Bereiche des oberen Gesichtsschädels und einiger weniger Abschnitte des Neurokraniums des Pferdes in der magnetresonanztomographischen Darstellung. Tiere und Methoden Repräsentative magnetresonanztomographische Bilder von sechs Pferden aus insgesamt 40 untersuchten Patienten wurden ausgewählt. Keines der Pferde wies auf den verwendeten Bildern Veränderungen im Nasen-bzw. Oberkieferbereich auf. Drei Pferde (Nr. 1, 2 und 6) wurden aufgrund verschiedener Befunde vor der Untersuchung euthanasiert. Die Untersuchungen fanden unmittelbar nach Euthanasie und Absetzen der Köpfe bzw. Hälse statt. Die anderen Pferde befanden sich während der Bilderstellung in einer Inhalationsnarkose. Die Untersuchungen erfolgten in der Klinik für Pferde der LMU München mit einem Magnetom Symphony der Firma Siemens (1,5 Tesla) sowie der Spine bzw. Wirbelsäulenspule und einer "CP Body Array Extender". Routinemäßig wurden transversale, sagittale und koronare Schnitte sowie teilweise fettunterdrückte Sequenzen als Spinechos und Gradientenechos angefertigt. Dabei wurden T1-gewichtete (T1w), T2-gewichtete (T2w) und T2stir (Short-Tau-inversion-recovery) Bilder gewonnen. Die STIR-Technik dient der Unterdrückung des "Fettsignals". Einheitlich ist mit einer Matrix von 256*256, einem FOV3-400 und einer Schichtdicke von 5 mm gearbeitet worden. Die Bilder wurden als DICOM abgespeichert und weiterverarbeitet. Transversale Schnitte orientierten sich jeweils im rechten Winkel zum harten Gaumen und die dorsalen möglichst parallel dazu. Für die sagittalen wurde die Nasenscheidewand als parallele Orientierung der angelegten Schnitte gewählt.