RT Journal Article
SR Electronic
T1 Postoperative Transient Reduced Diffusion in the Ipsilateral Striatum and Thalamus
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 524
OP 532
DO 10.3174/ajnr.A3242
VO 34
IS 3
A1 K. Kamiya
A1 N. Sato
A1 Y. Nakata
A1 K. Ito
A1 Y. Kimura
A1 M. Ota
A1 A. Takahashi
A1 H. Mori
A1 A. Kunimatsu
A1 K. Ohtomo
YR 2013
UL http://www.ajnr.org/content/34/3/524.abstract
AB BACKGROUND AND PURPOSE: Restriction of diffusion has been reported in the early phase of secondary neuronal degeneration, such as Wallerian degeneration. The purpose of this study was to investigate postoperative transient reduced diffusion in the ipsilateral striatum and thalamus as a remote effect of surgery. MATERIALS AND METHODS: Six hundred two postoperative MR imaging examinations in 125 patients after cerebral surgery were retrospectively reviewed, focusing on the presence of reduced diffusion in the striatum and/or thalamus. The distribution of reduced diffusion in the striatum was classified into 3 groups: anterior, central, and posterior. Reduced diffusion in the thalamus was also classified on the basis of the anatomic locations of the thalamic nuclei. Further follow-up MRI was available in all patients with postoperative reduced diffusion, and acute infarctions were excluded. The patient medical records were reviewed to evaluate neurologic status. RESULTS: Restriction of diffusion was observed in the striatum and/or thalamus ipsilateral to the surgical site in 17 patients (13.6%). The distribution of signal abnormality correlated with the location of the operation, in concordance with the architecture of the striatocortical and thalamocortical connections. Reduced diffusion was observed from days 7 to 46 after the operation, especially during days 8–21. The signal abnormalities completely resolved on follow-up examinations. The median follow-up period was 202 days (interquartile range, 76–487 days). CONCLUSIONS: Postoperative transient reduced diffusion in the ipsilateral striatum and/or thalamus likely represents an early phase of secondary neuronal degeneration based on its characteristic distribution and time course. Clinically, this reduced diffusion should not be mistaken for postoperative ischemic injury. GABAgamma-aminobutyric acidOFCorbitofrontal cortexPFCprefrontal cortexrADCrelative ADC ratioWHOWorld Health Organization