Magnetic resonance imaging of an equine ependymoma

Abstract

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...

Cerebral malacia in a mule with ependymoma

“…; Leser et al . ), this paper represents the first time this tumour has been described in a mule ( Equus asininus × Equus caballus ) with concomitant cerebral malacia.…”

“…As well as the possible neoplastic differential diagnoses, cholesteatoma (cholesterol granuloma) should also be a consideration in equids (Leser et al . ). This lesion is characterised by the development of a tumour‐like mass, located in brain ventricles, found in 15–20% of older horses, and can be associated with neurological clinical signs (Jackson et al .…”

“…; Leser et al . ). As we suspect has probably occurred in this case, secondary pathology may develop and result in significant neurological signs.…”

3-Tesla magnetic resonance imaging of the equine brain in healthy horses – Potentials and limitations

“…According to Holmes (2013), this is also true for equine patients. MRI has been used as a diagnostic tool in several neurologically affected horses, like: Features of nigropallidal encephalomalacia (Sanders et al 2001), cerebral abscess, encephalomalacia, nigropallidal encephalomalacia, internal hydrocephalus, otitis media and interna (Ferrell et al 2002), metastatic brain abscesses in horses with strangles (Spoormakers et al 2003), brain abscess in a filly (Audigié et al 2004), brainstem meningioma in a pony (Dyson et al 2007), ocular angiosarcoma in a pony (Bischofberger et al 2008), cholesterol granuloma (Maulet et al 2008), ependymoma (Leser et al 2013), retrobulbar meningioma (Naylor et al 2010), cerebellar abiotrophy (Pongratz et al 2010, Cavalleri et al 2013, external and an internal hydrocephalus (Oey et al 2011), posttraumatic epilepsy , Chiari malformation in a foal (Lempe et al 2012), features of closed head trauma in two foals (De Zani et al 2013). Anatomical studies of the equine brain in MRI have been performed in foals (Chaffin et al 1997) and in adult horses (Arencibia et al 2001), however, with varying settings: Chaffin et al (1997) used a very low field strength of 0.35 Tesla; Arencibia et al (2001) examined a post mortem head (removed from the neck), using a magnet of 1.5 Tesla.…”