Patientenspezifische Schädeldachplastiken aus titanverstärktem Calciumphosphat bei komplikativen Kranioplastiepatienten

Cranioplasty (CP), the restoration of cranial integrity is routinely performed both following decompressive hemicraniectomy, and also as the final step of most intracranial operations. Complications can be severe with wound infections damaging the autologous bone and surrounding tissue typically requiring explantation. Eventually, these patients present for repeat CP to restore cranial integrity. In recent years, patient specific implants using titanium reinforced Calcium Phosphate (Ca-P PSI) have increasingly been utilized. This study aims to assess their applicability for repeat CP in complicative cases.

A single center retrospective analysis of all complicative cases treated with a Ca-P PSI as a repeat CP between 2020 and 2022 was performed. Demographic, perioperative and long-term follow-up data on the patients were collected and are presented descriptively.

We identified 15 patients (six male, nine female) implanted with a Ca-P PSI for repeat CP from 2016 to 2022. The cranial operations prior to the initial CP (CP1) were predominantly tumor excisions (n=9) and took place between 1991 and 2019. The first complication was noted on average 15 months after CP1. Reasons for explantation of the initial CP were mostly infections (n=13), though one CSF fistula and one epidural hematoma were noted. The first repeat CP (CP2) was performed in 12 cases using a Ca-P PSI. In four of those cases, a skin expander was utilized prior to CP2 and 12 of those patients were administered antibiotics postoperatively. In three patients, CP2 was performed using a material other than Ca-P. Complications requiring re-explantation were noted on average seven years after CP2 in those cases but in all, another CP (CP3) was attempted (2 Ca-P, 1 PMMA). The PMMA-implanted patient developed another wound infection and was finally treated with a Ca-P PSI (CP4) 11 months after explantation of the PMMA plastic. Overall, during a mean follow-up of 2.1 ± 0.6 years, four patients developed significant complications after CP with a Ca-P PSI, leading to explantation and definitive treatment with a myocutaneous flap.

Our data suggest that Ca-P PSI can be an asset for repeat CP in complicative cases. A possible reason could be osseous integration of the this material, yielding a physiological microenvironment potentially resilient to infections. However, further studies are warranted to elucidate the underlying mechanisms and develop guidelines for repeat CP.