Avoiding Side Effects of Brain Tumour Surgery | Action Medical Research | Children's Charity

Brain tumours: avoiding a serious side effect of surgery

This research was completed on 31 August 2015

Published on 18 January 2012

Around one in four children who undergo surgery to remove a tumour from the back of the brain – the cerebellum – develop a distressing side effect called cerebellar mutism syndrome.1 They lose the ability to speak and have difficulty coordinating their movements. Although their condition normally improves with time, children are often left with permanent disabilities. Professor Richard Apps, of the University of Bristol, is looking for a way to improve surgery and stop children from developing these life-changing disabilities.

What is the problem and who does it affect?

Brain tumours are the most common type of solid tumour in children.2 They most often occur in an area at the back of the brain called the cerebellum.3 Treatment of these tumours usually includes brain surgery, but around one in four children who undergo surgery develop a distressing side effect called cerebellar mutism syndrome.

“Children with cerebellar mutism syndrome usually develop symptoms one or two days after surgery. They suffer loss of speech and severe difficulties with movement, such as problems coordinating arm movements,” explains Professor Richard Apps. “Most children eventually recover to some extent, but this can take a long time. One year after diagnosis, for example, 92 per cent of affected children still have movement problems and 66 per cent have speech and language difficulties.1

No-one knows how to stop children from developing cerebellum mutism syndrome, or why some children are affected while others are not. “The syndrome can be a major burden for children and their families, having a severe impact on all aspects of daily life, and is costly to the NHS. It means children are likely to spend more time in hospital and need long-term support from a range of rehabilitation specialists.”

What is the project trying to achieve?

“We are investigating whether cerebellar mutism syndrome results from inadvertent damage to particular areas of the brain during surgery – areas that are important in language and movement,” explains Professor Apps. “We are finding out if it is possible to record brain activity during surgery to produce a ‘map’ of each child’s brain, showing which areas of each child’s brain are involved in language and movement.”

The mapping technique involves placing a small recording electrode directly onto the exposed surface of the brain during surgery. Around 18 children who are undergoing surgery are taking part in the study.

“If we are successful, we plan a clinical trial in around 100 children to see if this mapping technique has long-term benefits. By helping surgeons to remove tumours while minimising damage to key areas of the brain, we believe this might spare children from the distressing effects of cerebellar mutism syndrome.”

What are the researchers’ credentials?

Project LeaderProfessor R Apps PhD
Project team
  • Dr R Edwards FRCS
  • Dr R Ashida MBChB MRCS
LocationSchool of Physiology and Pharmacology, University of Bristol and Department of Neurosurgery
Other locations
  • Bristol Institute of Clinical Neurosciences, Frenchay Hospital, Bristol
Duration18 months
Grant awarded22 August 2011
Start date1 August 2012
End date31 August 2015
Grant amount£98,120.00
Grant codeSP4619, GN1804

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This study builds on the combined expertise of the project team. Professor Apps and his colleague from the University of Bristol, Dr Nadia Cerminara, are world-leading experts in mapping brain activity in the cerebellum. The third team member, Dr Richard Edwards, has considerable experience of brain surgery in children.


  1. Wells EM, Walsh KS, Kademian ZP, Keating RF & Packer RJ. The cerebellar mutism syndrome and its relation to cerebellar cognitive function and the cerebellar cognitive affective disorder. Developmental Disabilities Research Reviews 2008; 14, 221-228
  2. Cancer Research UK. Accessed January 2012. http://cancerhelp.cancerresearchuk.org/type/brain-tumour/about/brain-tumour-risks-and-causes
  3. Patient.co.uk. Cancer of the brain and brain tumours. http://www.patient.info/health/Cancer-of-the-Brain-and-Brain-Tumours.htm
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