Clinical Trial: Swiss Prospective Autologous Bone Flap Resorption Study

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Swiss Prospective Autologous Bone Flap Resorption Study

Brief Summary: The complications after reimplantation of cryoconserved autologous bone flaps are reported inhomogeniously in the literature. Especially the incidence of bone flap resorption varies from 0% to about 30%. More recent retrospective studies seem to find higher resorption rates and thus suggest to implant artificial bone replacements from the start. The Swiss Prospective Autologous bone Resorption Study is the first propspective observational study designed to determine the true incidence of autologous bone resorption.

Detailed Summary:

Patients undergoing decompressive craniectomy and delayed reimplantation of the cryoconserved autologous bone flap are included in a clinical and image-based follow-up to identify cases and severity of bone flap resorption.

The explanted autologous bone flaps are cryoconserved and reimplanted at a time-point defined by the surgeon according to standards of the participating hospital. The fixation of the bone flap is also performed according to the surgeon's decision.

A cranial CT is performed within one week after reimplantation to define a baseline.

A second, only clinical, follow-up will take place within 2 months after reimplantation.

Two more follow-ups including photodocumentation of the cranial and facial symmetry (portrait and profile) and cranial CT will take place 12 and 24 months after reimplantation.

The indication for surgical revision in case of bone flap resorption is independent from the study and falls under the responsibility of the treating surgeon.


Sponsor: University of Zurich

Current Primary Outcome: Incidence of a relevant bone resorption within 12 months after reimplantation [ Time Frame: 12 months ]

The extent of bone flap resorption is analyzed as well objectivela as subjectivels:

objective criteria: Volumetric reconstruction of the bone flap from the CT scans and subtration of the actual bone flap volume from the 3D model at the basline-timepoint directly after reimplantation

subjective: a bone flap resorption score is validated



Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Incidence of an indication for surgical revision [ Time Frame: 12 and 24 months after reimplantation ]
    The indication for a surgical revision falls under responsibility of the treating surgeon.
  • Death [ Time Frame: 2, 12 and 24 months after reimplantation ]
    death
  • Infections [ Time Frame: 2, 12 and 24 months after reimplantation ]
    Infections
  • Fluid collections and bleedings [ Time Frame: 2, 12 and 24 months after reimplantation ]
    subgaleal, epidural and subdural fluid collections and hematomas
  • Hydrocephalus [ Time Frame: 2, 12 and 24 months after reimplantation ]
    hydrocephalus
  • Temporal muscle atrophy [ Time Frame: 2, 12 and 24 months after reimplantation ]
    temporal muscle atrophy
  • timepoint between explantation and reimplantation [ Time Frame: 2, 12 and 24 months after reimplantation ]
    measured in months
  • patient age [ Time Frame: 2, 12 and 24 months after reimplantation ]
    in years
  • fragmentation of the bone flap [ Time Frame: 2, 12 and 24 months after reimplantation ]
    in number of pieces
  • temperature used for cryoconservation [ Time Frame: 2, 12 and 24 months after reimplantation ]
    in °C
  • pathologies leading to explantation of the bone flap (hemicraniectomy) [ Time Frame: 2, 12 and 24 months after reimplantation ]
    trauma, tumor, stroke and others


Original Secondary Outcome: Same as current

Information By: University of Zurich

Dates:
Date Received: December 10, 2014
Date Started: January 2015
Date Completion: June 2019
Last Updated: May 2, 2017
Last Verified: May 2017