LAUSR

I read the article ‘Acute amnestic syndrome in isolated bilateral fornix stroke’ [1] with great interest. The authors described three cases having an isolated bilateral anterior fornix infarction and an acute amnestic syndrome. There was a cytotoxic edema in bilateral anterior columns of the fornix and also a bilateral narrowing of the anterior cerebral artery. They concluded that bilateral fornix infarction should be considered in acute onset of an amnestic syndrome. I agree with their recommendation in combination with exploring non-vascular changes, and I want to add some information about their study. Azevedo Kauppila et al. [2] presented the same case with neuropsychological follow-up data. A 68-year-old woman with an unruptured aneurysm of the anterior communicating artery was submitted to endovascular treatment. Brain magnetic resonance imaging showed an acute infarction of both anterior pillars of the fornix. Six months later, the neuropsychological revaluation showed a significant improvement of some deficits, and there were no topographic impairments in daily life, keeping this improvement during the next 6 months. This case demonstrated clearly the functional contribution of the fornix to memory function. They summarized nine cases of isolated injury of the fornix, and two cases with follow-up data involved lesions of the fornix and other brain structures. Injuries in the fornix exclusively or involving other structures should be specified for understanding the mechanism of acute amnestic syndromes. Secondly, Ren et al. [3] presented a 66year-old woman with memory impairment due to a small acute infarction of the columns of the fornix. In addition, they conducted a literature review of 15 cases of infarction of the columns of the fornix, and the prognosis in 10 cases varied. The follow-up periods also varied and injuries in seven cases were not located in the columns of the fornix. Pardina-Vilella et al. [4] presented a case with acute-onset amnestic syndrome, presenting infarction in the corpus callosum genu and both fornices. They proposed ‘the goblet sign’ for the peculiar diffusion-weighted magnetic resonance image of the subcallosal artery infarction. Anyway, additional reports are needed for clarifying the trend of prognosis by specifying the locations of injury.