title: Changes in volume of giant intracranial aneurysms treated by surgical strategies other than direct clipping.
abstract: BACKGROUND
  Giant intracranial aneurysms (GIA) are often not eligible for direct clip occlusion. Surgical alternatives include partial clip occlusion or the placement of a cerebrovascular bypass or the combination of both. These alternative indirect strategies are expected to lead to a decrease in GIA volume over time rather than instantaneously. To examine whether this is the case, we analyzed follow-up imaging results 1 year after surgery.
  
  
  METHODS
  We retrospectively screened the prospective GIA Registry's imaging database for anterior circulation GIA treated by surgical strategies other than direct clipping. We measured pre- and 1-year post-treatment GIA volume, lateral ventricle volume (LVV), and mid-line shift (MLS) in 19 cases.
  
  
  RESULTS
  After a mean follow-up of 466 days (standard deviation ±171) GIA volumes decreased from 9.6 cm(3) (interquartile range (IQR) 6.1-14.1) to 4.3 cm(3) (IQR 2.9-5.7; p < 0.01). Ipsilateral LVV increased from 8.6 cm(3) (IQR 6.4-24.9) to 16.0 cm(3) (IQR 9.1-27.2; p < 0.01) while contralateral LVV increased from 10.3 cm(3) (IQR 7.3-20.1) to 11.7 cm(3) (IQR 8.2-19.4; p = 0.02). MLS changed from 0.1 mm (IQR -1.9 to 2.0) to -0.9 mm (IQR -1.8 to 0.4; p = 0.03). The decrease in GIA volume correlated with the increase in ipsilateral LVV (rs = 0.60; p = 0.01) but not with the changes in MLS (rs = 0.41; p = 0.08).
  
  
  CONCLUSIONS
  In our patient cohort, surgical strategies other that direct clipping for the treatment of anterior circulation GIA lead to a significant decrease in GIA volume over time. The resulting decrease in mass effect was more sensitively monitored by the measurement of changes in ipsilateral LVV than changes in MLS.
  
  
  BACKGROUND
  http://www.clinicaltrials.gov . Unique identifier: NCT02066493.
authors.affiliation: Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Nicolai
authors.initials: N
authors.lastname: Maldaner
authors.forename: Susanne
authors.initials: S
authors.lastname: Guhl
authors.forename: Dorothee
authors.initials: D
authors.lastname: Mielke
authors.forename: Christian
authors.initials: C
authors.lastname: Musahl
authors.forename: Nils Ole
authors.initials: NO
authors.lastname: Schmidt
authors.forename: Maria
authors.initials: M
authors.lastname: Wostrack
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Rüfenacht
authors.forename: Peter
authors.initials: P
authors.lastname: Vajkoczy
authors.forename: Julius
authors.initials: J
authors.lastname: Dengler
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D012189:Retrospective Studies; D013525:Surgical Instruments / Q000009:adverse effects*