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MRI protocols for imaging paediatric brain tumours
Clinical Radiology 67 (2012) 829e832
Contents lists available at SciVerse ScienceDirect
Clinical Radiology journal homepage: www.clinicalradiologyonline.net
Review
MRI protocols for imaging paediatric brain tumours E. Craig a, D.J.A. Connolly a, b, P.D. Griffiths c, A. Raghavan a, V. Lee d, R. Batty a, b, * a
Department of Radiology, Sheffield Children’s Hospital, UK Department of Radiology, Royal Hallamshire Hospital, UK c Academic Unit of Radiology, University of Sheffield, UK d Department of Oncology, Sheffield Children’s Hospital, Sheffield, UK b
art icl e i nformat ion Article history: Received 14 February 2012 Received in revised form 15 March 2012 Accepted 27 March 2012
AIMS: To establish whether paediatric centres within the Children’s Cancer and Leukaemia Group (CCLG) network employ magnetic resonance imaging (MRI) protocols for brain tumours according to the revised guidance. MATERIALS AND METHODS: Questionnaires were sent to both consultants and superintendent radiographers in the 21 centres within the CCLG network that perform MRI on paediatric brain tumour patients. Information was requested as to whether the centre had a protocol for imaging paediatric brain tumours, which sequences were performed, and whether these were used by all consultants. RESULTS: Twenty-seven completed questionnaires out of the 42 sent were returned, which included responses from 17 of the 21 UK centres. The majority of centres had a protocol for MRI of paediatric brain tumours at all stages of treatment. The standardized CCLG MRI sequences were incorporated in full at only five of the 17 centres. CONCLUSION: The standard sequences of the CCLG brain imaging protocol are poorly adhered to nationally. Further awareness of the revised protocol is needed, with improved access to the guidelines for non-CCLG members on the CCLG and Royal college of Radiologists website. Ó 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction Paediatric brain tumours are uncommon and many patients are entered into national or international clinical trials for chemotherapeutic regimes. The images, therefore, are often assessed for disease response not only at the individual centre but also by the coordinators of clinical trials. In 1999 a protocol was published by the United Kingdom Childhood Cancer Study Group (UKCCSG) for magnetic resonance imaging (MRI) of paediatric brain tumours.1e3 The protocol was introduced in the hope of * Guarantor and correspondent: R. Batty, Department of Radiology, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2PT, UK. Tel.: þ44 (0) 1142 711900. E-mail address: [email protected] (R. Batty).
enabling accurate and reliable comparisons of images performed at different centres across the UK (Tables 1 and 2). Despite the protocol, radiologists performing the secondary review of images for clinical trials report that the sequences performed can vary both within and between centres. This makes accurate tumour volume assessment in response to treatment extremely difficult. Unsurprisingly, this reflects the advances in MRI technology since the original protocol was proposed in 1999, the wide variety of MRI systems utilized, and the preferences of the individual radiologist. The protocol was revised by the Children’s Cancer and Leukaemia Group (CCLG) in 20094 to reflect the technological advances (Tables 3 and 4), with a plan that, in future, failure to adhere to the revised imaging protocols would result in new cases being excluded from recruitment to CCLG studies. Currently, the imaging guidelines are to be
0009-9260/$ e see front matter Ó 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2012.03.018
830
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
Table 1 Summary of the UKCCSG 1999 Guidelines for MR imaging of supratentorial tumours in paediatric patients.1e3
Table 3 Summary of CCLG 2009 standard MR imaging sequences for paediatric brain tumours.4
Sequence
Presentation
Post surgery (within 72 hours)
Late follow up
Sequence
Presentation Post surgery Late (within 72 hours) follow up
Axial dual echo SE/FSE Coronal T1 SE T1 SE þ contrast in at least 2 planes Sagittal T1 whole spine þ contrast þ/ axial T1 SE
U U U
U U U
U U U
Axial T1 Axial T2 Coronal FLAIR DTI þ/ DWI (þ ADC maps) Axial/Coronal/Sagittal T1 þ contrast (1.5T) Axial T1, Axial 3D T1 Volume þ contrast (3T) Sagittal T1 spine þ contrast þ/ axial T1
U U U U
U U U U
U U U U
U
U
U
U
U
U
U
b
a
a
a
U
Depending on histology of brain tumour.
found on the member’s only area of the CCLG website, which is password protected.4 The British Society for Paediatric Radiology (BSPR) on their website5 still advocates the out-dated 1999 UKCCSG guidelines. A standardized MRI protocol is necessary6 if MRI performed at the same or at several different centres within the UK is to be reliably compared to assess tumour response to treatment; the standard CCLG protocol4 may not have been applied due to a lack of awareness. The purpose of the study was therefore to assess compliance with the CCLG guidelines nationally.
Materials and methods A postal audit of all paediatric centres within the CCLG network was conducted in June 2011 to establish which MRI sequences were used. The standards for the audit were that all centres within the CCLG group should image paediatric patients with brain tumours to include sequences as per the revised 2009 CCLG guidelines4 (Table 3). All centres should have an MRI protocol for imaging paediatric brain tumours at presentation, postoperatively, and at follow-up. The same protocol should be used by all consultants within that centre. Our target for these standards was 100%. A questionnaire was posted to both consultants and superintendent radiographers separately at the 21 paediatric centres within the CCLG network. The questionnaire required tickbox responses as to which sequences from a list they performed at presentation, postoperatively, and at follow up. Table 2 Summary of the UKCCSG 1999 Guidelines for MR imaging of infratentorial brain tumours in paediatric patients.1e3 Sequence
Presentation
Axial T1 SE
U
Coronal T1 SE
U
U
U
Axial T2 SE/FSE
U
U
U
T1 SE þ contrast in at least 2 planes Sagittal T1 whole spine þ contrast
U U
Post surgery (within 72 hours)
U
Late follow up
U U
a b
Depending on histology of brain tumour. Only if not performed prior to surgery.
There was the capacity to mention other sequences not included on the original list. Further questions were asked as to whether the centre had a departmental protocol, if the protocol was used by all consultants, for all grades of tumours, and/or at all locations. In the few instances where a difference was identified in the responses between consultant radiologist and superintendent radiographer at a particular centre, the consultants’ responses were recorded as they were ultimately responsible for selecting the appropriate imaging sequences on the request cards. However, it is accepted that this may not be a reliable method of recording actual rather than physician-perceived clinical practice.
Results Forty-two questionnaires were posted and 27 (64%) completed questionnaires were returned. This resulted in responses from 17 of the 21 centres (81%) within the network. From 10 centres, completed responses were received from both the consultant radiologist and the superintendent radiographer. Responses were received from consultants only at two centres, and from the remaining five centres the superintendent radiographers completed the questionnaire. The majority (16/17) of the responding centres did have a departmental protocol for imaging patients at presentation, post-surgery, and at follow-up. At one centre, postoperative images were not performed there as the surgery was carried out elsewhere. At 94% (16/17) of centres the Table 4 Optional CCLG 2009 MRI sequences for imaging paediatric brain tumours. (Dependent on local capacity, availability or CCLG trial involvement).4 Sequence
Presentation
Coronal/Sagittal T2 or FLAIR MR Perfusion MRS ASL Sagittal T2 Spine
U U U U U
Post surgery
Follow up U U U U U
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
same protocol was used by all consultants. The same protocol was used in 88% (15/17) of centres independent of the grade of the tumour. Forty-seven percent (8/17) of centres used the same protocol for all tumour locations. The results of the questionnaire were initially compared with the UKCCSG 1999 protocol1e3 and it was found that none of the 17 centres who responded included all of the recommended sequences within their protocol. One centre included, for its infratentorial tumours only, the sequences as recommended by the UKCCSG.1e3 A further two centres included all the sequences for supratentorial tumours at presentation and at follow-up, but not for the postoperative imaging or for infratentorial tumours. The two main reasons for failing to comply with the guidelines were the omission of the axial dual-echo sequence with most centres preferring to include an axial fast spin-echo, T2-weighted sequence; and failure to include the coronal, T1-weighted sequence. Subsequently, the sequences performed at the centres within the network were compared with the revised CCLG 2009 protocol4 (Fig 1). Five out of the 17 centres included the full CCLG protocol for imaging paediatric brain tumours. One centre included all the sequences at presentation only, but did not include the coronal, fluid-attenuated inversion recovery (FLAIR) at other stages of the care pathway. Another centre included all the sequences in its presentation and follow-up protocols, but did not include diffusionweighted imaging (DWI) and/or diffusion tensor imaging (DTI) in its postoperative protocol. The sequence most frequently missed in the protocols was coronal FLAIR imaging. Few centres performed the axial, T1-weighted and the contrast-enhanced, axial, three-dimensional (3D), T1weighted, volume-rendered sequence with at 3 T. The optional sequences included in the 2009 CCLG protocol
831
(Fig 1) were included in their entirety within the protocol of one centre only.
Discussion Despite the apparent awareness of the importance of a standardized set of sequences, as set out by the UKCCSG in 19991e3 and again by the CCLG in 2009,4 there is a lack of consistency in the imaging performed between and within UK centres. This audit has shown that no centres adhered to the 1999 imaging protocol and only five of the 17 to the revised protocol. This causes difficulties in making an accurate comparison of images performed on the same patient at different centres or nationally/internationally when patients are recruited to clinical trials. The lack of compliance may be due to a lack of clarity over which sequences are recommended within the CCLG network.4 Currently, the BSPR includes the 1999 UKCCSG guidelines5 on its website, which have been superseded. The 2009 revised protocol is available on the CCLG website but in a password-protected member’s only area. Centres performing imaging, which could eventually form part of CCLG research, may not have access to these protocols. This could potentially result in MRI not being performed to the required specification. There may be a significant increase in the number of patients who are excluded from CCLG trials due to non-compliance with the CCLG imaging protocols. The diagnostic and, in particular, follow-up imaging protocols of peripheral hospital for these patients were not recorded. A considerable proportion of the follow-up imaging of some of the CCLG network centres occurs at other hospitals. Long, prescriptive protocols are often poorly adhered to, whether due to a lack of awareness of updated protocols, the capabilities of the systems, or the radiologists’ own
Figure 1 Graph showing the number of centres within the network performing each of the sequences recommended by the CCLG at presentation, post operatively and at follow up.
832
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
preferences. Ideally as T1 and FLAIR 3D volume imaging improves and becomes widely available, it could form a basis to simplify MRI protocols and achieve consistency between centres. Volume imaging provides an objective measurement of tumour growth or response to treatment.7,8 Modern assessment of tumour type, response to surgery, radiotherapy, and chemotherapy may utilize complimentary sequences such as MR spectroscopy, DTI, and MR perfusion. These sequences allow greater accuracy in making the initial diagnosis, aid further characterization9,10 of the tumour, and monitor response to treatment.9,10 The combined use of DWI and MR spectroscopy has been shown to be able to discriminate between tumours within the posterior fossa11 and help discriminate between the effects of treatment and recurrence of tumour. DWI can be used to estimate the cellularity of a tumour; apparent diffusion coefficient (ADC) values are inversely correlated with tumour grade.10,12 However, within many centres within the UK the use of MR spectroscopy, MR perfusion, and DTI is limited. In conclusion, the standard sequences of the CCLG brain imaging protocol are poorly adhered to nationally. Increased awareness and easier access to the current guidelines will hopefully improve compliance and allow more accurate pre-treatment assessment and treatment response assessment. As MRI technology progresses and volume imaging becomes universally available, further simplification of the guidelines may be possible.
References 1. Griffiths PD. A protocol for imaging paediatric brain tumours. United Kingdom Children’s Cancer Study Group and Societe Franc¸oise d’Oncologie Pediatrique Panalists. Clin Radiol 1999;54(9):558e62. 2. Griffiths PD. A protocol for imaging paediatric brain tumours. United te Franc¸aise d’OncoKingdom Children’s Cancer Study Group and Socie diatrique Panelists. Clin Oncol 1999;54(5):290e4. logie Pe 3. Thiesse P, Jaspan T, Couanet D, et al. Un protocole d’imagerie des tumeurs cerebrales de l’enfant (A protocol for imaging pediatric brain tumors). J Radiol 2001;82:11e6. 4. Jaspan T. CCLG brain tumour imaging protocol. CCLG website. Available at:, www.cclg.org.uk; January 2009 [accessed 25. 10. 2011]. 5. British Society of Paediatric Radiology website. Available at: http:// www.bspr.org.uk/mricns.htm. [accessed June 2011]. 6. Saunders DE. Magnetic resonance imaging protocols for paediatric neuroradiology. Pediatr Radiol 2007;37:789e97. 7. Norden AD, Young GS, Setayesh K, et al. Bevacizumab for recurrent malignant gilomas: efficacy, toxicity, and patterns of recurrence. Neurology 2008;70:779e87. 8. Wen PY, Macdonald DR, Reardon DA, et al. Updated response assessment criteria for high grade gilomas: response assessment in Neurooncology Working Group. J Clin Oncol 2010;28:1963e72. 9. Peet AC, Arvanitis TN, Auer DP, et al. The value of magnetic resonance spectroscopy in tumour imaging. Arch Dis Childhood 2008;93:725e7. 10. Rossi A, Gandolfo C, Morana G, et al. New MRI sequences (diffusion, perfusion, spectroscopy) in brain tumours. Paediatr Radiol 2010;40:999e1009. 11. Schneider JF, Viola A, Confort-Gouny S, et al. Infratentorial pediatriic brain tumours: the value of new imaging modalities. J Neuroradiology 2007;34:49e58. 12. Rao P. Role of MRI in paediatric neurooncology. Eur J Radiol 2008;68:259e70.
Contents lists available at SciVerse ScienceDirect
Clinical Radiology journal homepage: www.clinicalradiologyonline.net
Review
MRI protocols for imaging paediatric brain tumours E. Craig a, D.J.A. Connolly a, b, P.D. Griffiths c, A. Raghavan a, V. Lee d, R. Batty a, b, * a
Department of Radiology, Sheffield Children’s Hospital, UK Department of Radiology, Royal Hallamshire Hospital, UK c Academic Unit of Radiology, University of Sheffield, UK d Department of Oncology, Sheffield Children’s Hospital, Sheffield, UK b
art icl e i nformat ion Article history: Received 14 February 2012 Received in revised form 15 March 2012 Accepted 27 March 2012
AIMS: To establish whether paediatric centres within the Children’s Cancer and Leukaemia Group (CCLG) network employ magnetic resonance imaging (MRI) protocols for brain tumours according to the revised guidance. MATERIALS AND METHODS: Questionnaires were sent to both consultants and superintendent radiographers in the 21 centres within the CCLG network that perform MRI on paediatric brain tumour patients. Information was requested as to whether the centre had a protocol for imaging paediatric brain tumours, which sequences were performed, and whether these were used by all consultants. RESULTS: Twenty-seven completed questionnaires out of the 42 sent were returned, which included responses from 17 of the 21 UK centres. The majority of centres had a protocol for MRI of paediatric brain tumours at all stages of treatment. The standardized CCLG MRI sequences were incorporated in full at only five of the 17 centres. CONCLUSION: The standard sequences of the CCLG brain imaging protocol are poorly adhered to nationally. Further awareness of the revised protocol is needed, with improved access to the guidelines for non-CCLG members on the CCLG and Royal college of Radiologists website. Ó 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction Paediatric brain tumours are uncommon and many patients are entered into national or international clinical trials for chemotherapeutic regimes. The images, therefore, are often assessed for disease response not only at the individual centre but also by the coordinators of clinical trials. In 1999 a protocol was published by the United Kingdom Childhood Cancer Study Group (UKCCSG) for magnetic resonance imaging (MRI) of paediatric brain tumours.1e3 The protocol was introduced in the hope of * Guarantor and correspondent: R. Batty, Department of Radiology, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2PT, UK. Tel.: þ44 (0) 1142 711900. E-mail address: [email protected] (R. Batty).
enabling accurate and reliable comparisons of images performed at different centres across the UK (Tables 1 and 2). Despite the protocol, radiologists performing the secondary review of images for clinical trials report that the sequences performed can vary both within and between centres. This makes accurate tumour volume assessment in response to treatment extremely difficult. Unsurprisingly, this reflects the advances in MRI technology since the original protocol was proposed in 1999, the wide variety of MRI systems utilized, and the preferences of the individual radiologist. The protocol was revised by the Children’s Cancer and Leukaemia Group (CCLG) in 20094 to reflect the technological advances (Tables 3 and 4), with a plan that, in future, failure to adhere to the revised imaging protocols would result in new cases being excluded from recruitment to CCLG studies. Currently, the imaging guidelines are to be
0009-9260/$ e see front matter Ó 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2012.03.018
830
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
Table 1 Summary of the UKCCSG 1999 Guidelines for MR imaging of supratentorial tumours in paediatric patients.1e3
Table 3 Summary of CCLG 2009 standard MR imaging sequences for paediatric brain tumours.4
Sequence
Presentation
Post surgery (within 72 hours)
Late follow up
Sequence
Presentation Post surgery Late (within 72 hours) follow up
Axial dual echo SE/FSE Coronal T1 SE T1 SE þ contrast in at least 2 planes Sagittal T1 whole spine þ contrast þ/ axial T1 SE
U U U
U U U
U U U
Axial T1 Axial T2 Coronal FLAIR DTI þ/ DWI (þ ADC maps) Axial/Coronal/Sagittal T1 þ contrast (1.5T) Axial T1, Axial 3D T1 Volume þ contrast (3T) Sagittal T1 spine þ contrast þ/ axial T1
U U U U
U U U U
U U U U
U
U
U
U
U
U
U
b
a
a
a
U
Depending on histology of brain tumour.
found on the member’s only area of the CCLG website, which is password protected.4 The British Society for Paediatric Radiology (BSPR) on their website5 still advocates the out-dated 1999 UKCCSG guidelines. A standardized MRI protocol is necessary6 if MRI performed at the same or at several different centres within the UK is to be reliably compared to assess tumour response to treatment; the standard CCLG protocol4 may not have been applied due to a lack of awareness. The purpose of the study was therefore to assess compliance with the CCLG guidelines nationally.
Materials and methods A postal audit of all paediatric centres within the CCLG network was conducted in June 2011 to establish which MRI sequences were used. The standards for the audit were that all centres within the CCLG group should image paediatric patients with brain tumours to include sequences as per the revised 2009 CCLG guidelines4 (Table 3). All centres should have an MRI protocol for imaging paediatric brain tumours at presentation, postoperatively, and at follow-up. The same protocol should be used by all consultants within that centre. Our target for these standards was 100%. A questionnaire was posted to both consultants and superintendent radiographers separately at the 21 paediatric centres within the CCLG network. The questionnaire required tickbox responses as to which sequences from a list they performed at presentation, postoperatively, and at follow up. Table 2 Summary of the UKCCSG 1999 Guidelines for MR imaging of infratentorial brain tumours in paediatric patients.1e3 Sequence
Presentation
Axial T1 SE
U
Coronal T1 SE
U
U
U
Axial T2 SE/FSE
U
U
U
T1 SE þ contrast in at least 2 planes Sagittal T1 whole spine þ contrast
U U
Post surgery (within 72 hours)
U
Late follow up
U U
a b
Depending on histology of brain tumour. Only if not performed prior to surgery.
There was the capacity to mention other sequences not included on the original list. Further questions were asked as to whether the centre had a departmental protocol, if the protocol was used by all consultants, for all grades of tumours, and/or at all locations. In the few instances where a difference was identified in the responses between consultant radiologist and superintendent radiographer at a particular centre, the consultants’ responses were recorded as they were ultimately responsible for selecting the appropriate imaging sequences on the request cards. However, it is accepted that this may not be a reliable method of recording actual rather than physician-perceived clinical practice.
Results Forty-two questionnaires were posted and 27 (64%) completed questionnaires were returned. This resulted in responses from 17 of the 21 centres (81%) within the network. From 10 centres, completed responses were received from both the consultant radiologist and the superintendent radiographer. Responses were received from consultants only at two centres, and from the remaining five centres the superintendent radiographers completed the questionnaire. The majority (16/17) of the responding centres did have a departmental protocol for imaging patients at presentation, post-surgery, and at follow-up. At one centre, postoperative images were not performed there as the surgery was carried out elsewhere. At 94% (16/17) of centres the Table 4 Optional CCLG 2009 MRI sequences for imaging paediatric brain tumours. (Dependent on local capacity, availability or CCLG trial involvement).4 Sequence
Presentation
Coronal/Sagittal T2 or FLAIR MR Perfusion MRS ASL Sagittal T2 Spine
U U U U U
Post surgery
Follow up U U U U U
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
same protocol was used by all consultants. The same protocol was used in 88% (15/17) of centres independent of the grade of the tumour. Forty-seven percent (8/17) of centres used the same protocol for all tumour locations. The results of the questionnaire were initially compared with the UKCCSG 1999 protocol1e3 and it was found that none of the 17 centres who responded included all of the recommended sequences within their protocol. One centre included, for its infratentorial tumours only, the sequences as recommended by the UKCCSG.1e3 A further two centres included all the sequences for supratentorial tumours at presentation and at follow-up, but not for the postoperative imaging or for infratentorial tumours. The two main reasons for failing to comply with the guidelines were the omission of the axial dual-echo sequence with most centres preferring to include an axial fast spin-echo, T2-weighted sequence; and failure to include the coronal, T1-weighted sequence. Subsequently, the sequences performed at the centres within the network were compared with the revised CCLG 2009 protocol4 (Fig 1). Five out of the 17 centres included the full CCLG protocol for imaging paediatric brain tumours. One centre included all the sequences at presentation only, but did not include the coronal, fluid-attenuated inversion recovery (FLAIR) at other stages of the care pathway. Another centre included all the sequences in its presentation and follow-up protocols, but did not include diffusionweighted imaging (DWI) and/or diffusion tensor imaging (DTI) in its postoperative protocol. The sequence most frequently missed in the protocols was coronal FLAIR imaging. Few centres performed the axial, T1-weighted and the contrast-enhanced, axial, three-dimensional (3D), T1weighted, volume-rendered sequence with at 3 T. The optional sequences included in the 2009 CCLG protocol
831
(Fig 1) were included in their entirety within the protocol of one centre only.
Discussion Despite the apparent awareness of the importance of a standardized set of sequences, as set out by the UKCCSG in 19991e3 and again by the CCLG in 2009,4 there is a lack of consistency in the imaging performed between and within UK centres. This audit has shown that no centres adhered to the 1999 imaging protocol and only five of the 17 to the revised protocol. This causes difficulties in making an accurate comparison of images performed on the same patient at different centres or nationally/internationally when patients are recruited to clinical trials. The lack of compliance may be due to a lack of clarity over which sequences are recommended within the CCLG network.4 Currently, the BSPR includes the 1999 UKCCSG guidelines5 on its website, which have been superseded. The 2009 revised protocol is available on the CCLG website but in a password-protected member’s only area. Centres performing imaging, which could eventually form part of CCLG research, may not have access to these protocols. This could potentially result in MRI not being performed to the required specification. There may be a significant increase in the number of patients who are excluded from CCLG trials due to non-compliance with the CCLG imaging protocols. The diagnostic and, in particular, follow-up imaging protocols of peripheral hospital for these patients were not recorded. A considerable proportion of the follow-up imaging of some of the CCLG network centres occurs at other hospitals. Long, prescriptive protocols are often poorly adhered to, whether due to a lack of awareness of updated protocols, the capabilities of the systems, or the radiologists’ own
Figure 1 Graph showing the number of centres within the network performing each of the sequences recommended by the CCLG at presentation, post operatively and at follow up.
832
E. Craig et al. / Clinical Radiology 67 (2012) 829e832
preferences. Ideally as T1 and FLAIR 3D volume imaging improves and becomes widely available, it could form a basis to simplify MRI protocols and achieve consistency between centres. Volume imaging provides an objective measurement of tumour growth or response to treatment.7,8 Modern assessment of tumour type, response to surgery, radiotherapy, and chemotherapy may utilize complimentary sequences such as MR spectroscopy, DTI, and MR perfusion. These sequences allow greater accuracy in making the initial diagnosis, aid further characterization9,10 of the tumour, and monitor response to treatment.9,10 The combined use of DWI and MR spectroscopy has been shown to be able to discriminate between tumours within the posterior fossa11 and help discriminate between the effects of treatment and recurrence of tumour. DWI can be used to estimate the cellularity of a tumour; apparent diffusion coefficient (ADC) values are inversely correlated with tumour grade.10,12 However, within many centres within the UK the use of MR spectroscopy, MR perfusion, and DTI is limited. In conclusion, the standard sequences of the CCLG brain imaging protocol are poorly adhered to nationally. Increased awareness and easier access to the current guidelines will hopefully improve compliance and allow more accurate pre-treatment assessment and treatment response assessment. As MRI technology progresses and volume imaging becomes universally available, further simplification of the guidelines may be possible.
References 1. Griffiths PD. A protocol for imaging paediatric brain tumours. United Kingdom Children’s Cancer Study Group and Societe Franc¸oise d’Oncologie Pediatrique Panalists. Clin Radiol 1999;54(9):558e62. 2. Griffiths PD. A protocol for imaging paediatric brain tumours. United te Franc¸aise d’OncoKingdom Children’s Cancer Study Group and Socie diatrique Panelists. Clin Oncol 1999;54(5):290e4. logie Pe 3. Thiesse P, Jaspan T, Couanet D, et al. Un protocole d’imagerie des tumeurs cerebrales de l’enfant (A protocol for imaging pediatric brain tumors). J Radiol 2001;82:11e6. 4. Jaspan T. CCLG brain tumour imaging protocol. CCLG website. Available at:, www.cclg.org.uk; January 2009 [accessed 25. 10. 2011]. 5. British Society of Paediatric Radiology website. Available at: http:// www.bspr.org.uk/mricns.htm. [accessed June 2011]. 6. Saunders DE. Magnetic resonance imaging protocols for paediatric neuroradiology. Pediatr Radiol 2007;37:789e97. 7. Norden AD, Young GS, Setayesh K, et al. Bevacizumab for recurrent malignant gilomas: efficacy, toxicity, and patterns of recurrence. Neurology 2008;70:779e87. 8. Wen PY, Macdonald DR, Reardon DA, et al. Updated response assessment criteria for high grade gilomas: response assessment in Neurooncology Working Group. J Clin Oncol 2010;28:1963e72. 9. Peet AC, Arvanitis TN, Auer DP, et al. The value of magnetic resonance spectroscopy in tumour imaging. Arch Dis Childhood 2008;93:725e7. 10. Rossi A, Gandolfo C, Morana G, et al. New MRI sequences (diffusion, perfusion, spectroscopy) in brain tumours. Paediatr Radiol 2010;40:999e1009. 11. Schneider JF, Viola A, Confort-Gouny S, et al. Infratentorial pediatriic brain tumours: the value of new imaging modalities. J Neuroradiology 2007;34:49e58. 12. Rao P. Role of MRI in paediatric neurooncology. Eur J Radiol 2008;68:259e70.