Gonçalves Rita, Walmsley Gemma, Maddox Thomas W
Department of Veterinary Science, Small Animal Teaching Hospital, University of Liverpool, Leahurst, Neston, UK.
Department of Musculoskeletal and Ageing Science, Institute of Lifecourse and Medical Sciences, University of Liverpool, Liverpool, UK.
J Vet Intern Med. 2025 Jul-Aug;39(4):e70095. doi: 10.1111/jvim.70095.
Information regarding repeat magnetic resonance imaging (MRI) findings in dogs with meningoencephalitis of unknown origin (MUO) is sparse and it is unknown whether brain atrophy occurs.
To determine whether brain atrophy occurs in MUO and evaluate if there is an association between atrophy and survival or relapse.
Twenty-three dogs diagnosed with MUO that underwent MRI of the brain on two occasions at least six months apart.
Retrospective study. Interthalamic adhesion thickness to brain height ratio (ITr), lateral ventricle to brain height ratio (LVr), interthalamic adhesion thickness/brain height to lateral ventricle/brain height (ITr/LVr), bicaudate ratio (BCR) and total parenchymal brain volume (TPBV) were measured on both MRI studies and compared.
Thirteen dogs relapsed and four died during the study period. Median time between MRIs was 12 months, and only one imaging study (1/23) was considered normal on the second scan. All MRI variables measured significantly changed between imaging studies, but only higher TPBV was associated with increased survival (OR = 1.59, CI = 1.006-2.51, p = 0.047); no variables were found to be associated with relapse. New lesions were identified in six dogs (four of which also showed contrast enhancing lesions), with 5/6 of these dogs subsequently relapsing.
Brain atrophy likely occurs in dogs with MUO and is associated with worse outcomes. Clinical relapse might be likely in dogs with new or contrast-enhancing lesions on repeat MRI, so more aggressive treatment should be considered in these dogs.
关于不明原因脑膜脑炎（MUO）犬重复磁共振成像（MRI）结果的信息稀少，且脑萎缩是否会发生尚不清楚。
确定MUO犬是否会发生脑萎缩，并评估萎缩与生存或复发之间是否存在关联。
23只被诊断为MUO的犬，至少间隔6个月接受了两次脑部MRI检查。
回顾性研究。在两次MRI检查中测量丘脑间粘连厚度与脑高度比（ITr）、侧脑室与脑高度比（LVr）、丘脑间粘连厚度/脑高度与侧脑室/脑高度（ITr/LVr）、双尾状核比（BCR）和脑实质总体积（TPBV），并进行比较。
在研究期间，13只犬复发，4只死亡。两次MRI检查的中位时间为12个月，第二次扫描时只有一项成像研究（1/23）被认为正常。所有测量的MRI变量在两次成像研究之间均有显著变化，但只有较高的TPBV与生存率增加相关（OR = 1.59，CI = 1.006 - 2.51，p = 0.047）；未发现任何变量与复发相关。在6只犬中发现了新病变（其中4只也显示有强化病变），这些犬中有5/6随后复发。
MUO犬可能会发生脑萎缩，且与较差的预后相关。重复MRI出现新病变或强化病变的犬可能会临床复发，因此对这些犬应考虑更积极的治疗。
