title: Assessing perfusion changes during whole brain irradiation for patients with cerebral metastases.
abstract: OBJECTIVE
  To assess perfusion changes within brain and correlate these with clinical symptoms during whole brain radiotherapy (WBRT) for cerebral metastases.
  
  
  METHODS
  Fourteen patients with cerebral metastases underwent dynamic CT perfusion scans during palliative whole brain irradiation. Perfusion scans were performed on Day 1 prior to initial radiotherapy treatment, then on Day 2, and on Day 5 immediately after completion of radiotherapy. Measurements of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and capillary surface area permeability product (PS) were performed for each perfusion scan, and daily symptom assessment was taken prior to initial perfusion scan and thereafter prior to each daily radiation treatment.
  
  
  RESULTS
  Utilizing Day 1 as baseline, a 19% increase (P = 0.033) was noted in PS at Day 2, (median 1.47 ml/100 g/min), which returned to Day 1 range at Day 5 (median 1.31 ml/100 g/min). When symptoms were correlated with perfusion parameters, a statistically significant association between change in MTT with change in headache scores was observed, baseline to Day 2 (P = 0.019), and a trend between change in nausea scores with change in CBV (P = 0.059) as well as change in MTT (P = 0.098), baseline to Day 5.
  
  
  CONCLUSIONS
  This study has demonstrated the feasibility of a non-invasive technique to assess changes occurring within the human brain during a course of radiation treatment. Dynamic perfusion tomography provides insight into the pathophysiological processes taking place and allows correlation with patient symptomatology.
authors.affiliation: Department of Radiation Oncology, Princess Margaret Hospital, Toronto, Ontario, Canada. barbara-ann.millar@rmp.uhn.on.ca
authors.forename: Barbara-Ann M
authors.initials: BA
authors.lastname: Millar
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Purdie
authors.forename: Ivan
authors.initials: I
authors.lastname: Yeung
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Pond
authors.forename: Susan
authors.initials: S
authors.lastname: Billingsley
authors.forename: Rebecca
authors.initials: R
authors.lastname: Wong
authors.forename: Peiman
authors.initials: P
authors.lastname: Haddad
authors.forename: C Shun
authors.initials: CS
authors.lastname: Wong
authors.forename: Normand
authors.initials: N
authors.lastname: Laperriere
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply* / Q000528:radiation effects*; D001932:Brain Neoplasms / Q000098:blood supply / Q000532:radiotherapy* / Q000556:secondary*; D002560:Cerebrovascular Circulation / Q000528:radiation effects*; D016371:Cranial Irradiation; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012039:Regional Blood Flow / Q000528:radiation effects; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed
references.citation: AJNR Am J Neuroradiol. 2002 May;23 (5):828-32
references.pmid: 12006286
references.citation: Radiology. 2002 Jan;222(1):227-36
references.pmid: 11756730
references.citation: Acta Neurochir (Wien). 1995;136(1-2):82-6; discussion 86-7
references.pmid: 8748832
references.citation: Neuroradiology. 2003 Jun;45(6):373-6
references.pmid: 12719953
references.citation: Eur J Cancer. 2002 Mar;38(4):487-96
references.pmid: 11872340
references.citation: Int J Radiat Oncol Biol Phys. 2000 Aug 1;48(1):53-8
references.pmid: 10924971
references.citation: AJNR Am J Neuroradiol. 2001 May;22(5):905-14
references.pmid: 11337336
references.citation: Brain Res. 2003 Apr 18;969(1-2):59-69
references.pmid: 12676365
references.citation: Phys Med Biol. 2001 Dec;46(12):3161-75
references.pmid: 11768498
references.citation: Eur Radiol. 2001;11(7):1220-30
references.pmid: 11471616
references.citation: Radiother Oncol. 1995 Feb;34(2):132-6
references.pmid: 7597211
references.citation: J Comput Assist Tomogr. 2004 Jan-Feb;28(1):55-62
references.pmid: 14716233
references.citation: Cancer Res. 2003 Sep 15;63(18):5950-6
references.pmid: 14522921
references.citation: AJNR Am J Neuroradiol. 2000 Mar;21(3):462-70
references.pmid: 10730636
references.citation: Melanoma Res. 1999 Dec;9(6):611-3
references.pmid: 10661774
references.citation: Radiology. 1999 Oct;213(1):141-9
references.pmid: 10540654