Table 2.

Causes of hypertrophic olivary degeneration in our cohort

	Unilateral HOD		Bilateral HOD
	n	%	n	%
Cerebrovascular diseases	24	62	17	30
Hemorrhage	14a	36	5a	9
Infarction	8	21	12	21
Arteriovenous malformation	1	3	0	0
Capillary venous malformation	1	3	0	0
Tumor	5b	13	3b	5
Prior surgery of the posterior fossa	3	8	1	2
Metronidazole	1	3	2	4
Multiple sclerosis	1	3	1	2
Encephalitis	0	0	1	2
Progressive multifocal leukoencephalopathy	0	0	1	2
Dandy-Walker variant	0	0	1	2
Unknownc	5	13	29	52

HOD: hypertrophic olivary degeneration, n: number

^aIncluding hemorrhages associated with cavernous malformations: 5 cases in unilateral HOD and 4 cases in bilateral HOD.

^bThree cases had glioma and two cases had metastatic tumors in unilateral HOD. All three cases who had bilateral HOD had glioma.

^cP<0.001 by χ² test.