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Cerebellar Mutism Syndrome (CMS)

By Jonathan Kjær Grønbæk, Morten Wibroe, Sebastian Toescu, Radek Fric, Birthe Lykke Thomsen, Lisbeth Nørgaard Møller, Pernilla Grillner, Bengt Gustavsson, Conor Mallucci, Kristian Aquilina, Greg Adam Fellows, Emanuela Molinari, Magnus Aasved Hjort, Mia Westerholm -Ormio, Rosita Kiudeliene, Katalin Mudra, Peter Hauser, Kirsten van Baarsen, Eelco Hoving, Julian Zipfel, Karsten Nysom, Kjeld Schmiegelow, Astrid Sehested, Marianne Juhler, René Mathiasen, on behalf of CMS study group

Cerebellar mutism syndrome (CMS) as a complication of cerebellar tumor surgery in children was investigated in these articles, which describe a large prospective international multicenter study. We enrolled 500 children who had surgery for a cerebellar tumor and followed them for a year after surgery to see if they developed signs of CMS and how they recovered afterwards. The main focus was on language disorders such as muteness or severely reduced speech, and in article 1 we were particularly interested in whether the surgical approach, the type and location of the tumor and the age of the child played a role in developing CMS. We found that the access route was not associated with risk of CMS, but the type of tumor, location near the brainstem, and younger age were associated with a higher risk – even when the effect of the other parameters was taken into account. Based on this, we concluded that the location of the tumor near connections between the cerebellum and cerebrum is decisive for affecting the language function in connection with the surgery, and that the type of tumor itself – and not the associated location – plays an important role.

Some of the children are re-operated on if residual tumor or recurrence is found on a control scan in the course after the first operation. In article 2, we were interested in whether there was a difference in the risk of CMS between the first and second operation. Contrary to our hypothesis, we found that the risk was lower with a secondary operation. We attributed this to three factors: that the primary operation may be a more complicated procedure, that the patients may be more severely affected before the first operation, and that there may be an effect of neuronal plasticity between the two operations.

The articles can be read via the following links:


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