Intraoperative fabrication of patient-specific moulded implants for skull reconstruction: single-centre experience of 28 cases.
BACKGROUND
Intraoperatively fabricated polymethylmethacrylate (PMMA) implants based on computer-designed moulds were used to improve cosmetic results after hard tissue replacement. To assess the implant's cosmetic and functional results we performed both subjective and objective assessments.


METHODS
This retrospective analysis was performed using a cohort of 28 patients who received PMMA implants between February 2009 and March 2012. The cosmetic and functional results were assessed using a patient questionnaire. Furthermore an objective volumetric subtraction score (0-100) was applied and implant thickness, as well as gaps and tiers, were measured.


RESULTS
Patients mainly judged their cosmetic result as "good". Two of the 28 patients found their cosmetic result unfavourable. The functional result and stability was mainly judged to be good. Measurements of implant thickness showed a very high correlation with the thickness of the contralateral bone. Volumetric subtraction led to a median quality of 80 on a scale from 0 to 100. Median gaps around the margins of the implant were 1.5 mm parietally, 1.7 mm frontally and 3.5 mm fronto-orbitally, and median tiers were 1.2 mm, 0 mm and 0 mm respectively. The overall rate of surgical revisions was 10.7 % (three patients). Two patients suffered from wound healing disturbances (7.1 %). The overall complication rate was comparable to other reports in the literature.


CONCLUSIONS
Implantation of intraoperatively fabricated patient-specific moulded implants is a cost-effective and safe technique leading to good clinical results with a low complication rate.
Department of Neurosurgery, Bern University Hospital, Freiburgstrasse 10, 3010, Bern, Switzerland, Lennart.stieglitz@insel.ch.
Lennart Henning
LH
Stieglitz
Nicolas
N
Gerber
Thomas
T
Schmid
Pasquale
P
Mordasini
Jens
J
Fichtner
Christian
C
Fung
Michael
M
Murek
Stefan
S
Weber
Andreas
A
Raabe
Jürgen
J
Beck
D003362:Cost-Benefit Analysis; D003399:Craniotomy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D017060:Patient Satisfaction; D019904:Polymethyl Methacrylate; D019736:Prostheses and Implants / Q000191:economics; D019651:Plastic Surgery Procedures / Q000379:methods*; D012189:Retrospective Studies; D012886:Skull / Q000601:surgery*; D016896:Treatment Outcome
D019904:Polymethyl Methacrylate