MRI FEATURES OF GLIOMATOSIS CEREBRI IN A DOG

Abstract

The features of gliomatosis cerebri involving the brainstem and cerebellum in a 3-year-old dog are described. In magnetic resonance (MR) images, there was diffuse loss of the cerebellar folia and cerebellar gray and white matter contrast. Multiple illdefined T2-hyperintensities were present in the cerebellar parenchyma. A poorly defined, T2-hyperintense mass effect was present ventral to the pons and rostral medulla. No contrast enhancement was noted. Cerebrospinal fluid (CSF) was normal. Postmortem examination was consistent with gliomatosis cerebri, based on compatible histopathology and immunohistochemical findings. Although rare, gliomatosis cerebri should be included as a differential for diffuse infiltrative central nervous system (CNS) lesions.

Bilateral Telencephalic Gliomatosis Cerebri in a Dog

“…Also in necrotizing leukoencephalitis mononuclear pleocytosis is generally found at cerebrospinal fluid analysis [13,29]. In our case mild mononuclear pleocytosis detected at CSF analysis was consistent with previous cases of GC in dogs in which normal or mild increased CSF cell count has been found [7,12,22]. Canine distemper meningoencephalitis has been reported in an adult dog showing diffuse bilaterally and symmetric T2 hyperintensity of the subcortical parietal and frontal white matter [30].…”

“…To date 12 cases of GC have been reported in dogs with multiple distributions of the lesions throughout the brain and spinal cord, while MRI patterns have been described in five cases [7,9,11,12,[22][23][24]. Three dogs had telencephalic involvement [9,11,13] but only one of them showed bilateral and symmetric white matter T2 and FLAIR hyperintensities without any apparent mass effect or anatomical distortion [11].…”

“…However, there are no reports on a similar disease in dogs. In this study the areas affected by neoplastic infiltration did not express contrast enhancement suggesting bloodbrain integrity [36] as described for low-grade gliomas [26][27][28] and GC in humans [16,37] as in dogs [9,11,22,24].…”

“…This condition gives a histological pattern, which strictly correlates with the hemispheric white matter signal changes seen on MRI [18][19][20]. In human medicine, MRI features of histologically confirmed GC include extensive, symmetrical, or asymmetrical and often poorly delineated T2-hyperintense lesions, which tend to be T1-iso to T1-hypointense with variable contrast enhancement [2,16,21,22]. However, these findings are considered nonspecific for GC so that the differential diagnosis includes immunomediated or virus induced white matter diseases, leukodystrophy, and other brain tumors such as primary brain lymphoma or glioblastoma multiforme [18].…”

A comparison of clinical, magnetic resonance imaging and pathological findings in dogs with gliomatosis cerebri, focusing on cases with minimal magnetic resonance imaging changes‡

“…Reports of canine GC generally give the impression of widespread disease, with frequent involvement of multiple divisions of the CNS . All six dogs in one study had involvement of at least two of the following: telencephalon, diencephalon, brainstem, cerebellum or spinal cord .…”