title: Rule of 5: angiographic diameters of cervicocerebral arteries in children and compatibility with adult neurointerventional devices.
abstract: OBJECTIVE
  The safety of using adult-sized neuroendovascular devices in the smaller pediatric vasculature is not known. In this study we measure vessel diameters in the cervical and cranial circulation in children to characterize when adult-approved devices might be compatible in children.
  
  
  METHODS
  For 54 children without vasculopathy (mean age 9.5±4.9 years (range 0.02-17.8), 20F/34M) undergoing catheter angiography, the diameters of the large vessels in the cervical and cranial circulation (10 locations, 611 total measurements) were assessed by three radiologists. Mean±SD diameter was calculated for the following age groups: 0-6 months, 1, 2, 3, 4, 5-9, 10-14, and 15-18 years. To compare with adult sizes, each vessel measurement was normalized to the respective region mean diameter in the oldest age group (15-18 years). Normalized measurements were compared with age and fitted to a segmented regression.
  
  
  RESULTS
  Vessel diameters increased rapidly from 0 to 5 years of age (slope=0.069/year) but changed minimally beyond that (slope=0.005/year) (R(2)=0.2). The regression model calculated that, at 5 years of age, vessels would be 94% of the diameter of the oldest age group (compared with 59% at birth). In addition, most vessels in children under 5, while smaller, were still potentially large enough to be compatible with many adult devices.
  
  
  CONCLUSIONS
  The growth curve of the cervicocerebral vasculature displays rapid growth until age 5, at which point most children's vessels are nearly adult size. By age 5, most neuroendovascular devices are size-compatible, including thrombectomy devices for stroke. Under 5 years of age, some devices might still be compatible.
authors.affiliation: Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA Cerebrovascular Program, Departments of Neurology and Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Lucy
authors.initials: L
authors.lastname: He
authors.affiliation: Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA Vanderbilt School of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Travis R
authors.initials: TR
authors.lastname: Ladner
authors.affiliation: Department of Radiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Sumit
authors.initials: S
authors.lastname: Pruthi
authors.affiliation: Department of Radiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Day
authors.affiliation: Department of Radiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Aditi A
authors.initials: AA
authors.lastname: Desai
authors.affiliation: Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Lori C
authors.initials: LC
authors.lastname: Jordan
authors.affiliation: Cerebrovascular Program, Departments of Neurology and Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Froehler
mesh_terms: D000293:Adolescent; D000375:Aging; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography / Q000009:adverse effects / Q000379:methods*; D002536:Cerebral Arteries / Q000000981:diagnostic imaging* / Q000254:growth & development; D002560:Cerebrovascular Circulation; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D061214:Patient Safety; D017131:Thrombectomy
keywords: Device; Intervention; Pediatrics; Technique; Vessel Wall