Treatment of very large cranial defects with individually shaped polypropylene polyester knitwear prostheses: a series of 11 cases

BACKGROUND Very large cranial defects are not very common in neurosurgical practice and there is not any widely acknowledged standard of their treatment. One of the useful methods in such cases is individual forming of polypropylene-polyester knitwear. Such material was used in the past but before 2008 it was available only as standardized plates. Currently, it can be also produced as individually-shaped implants. The authors give their definition of very large cranial defects and present their experience with this cranioplastic method in such defects. METHODS The authors collected data on 11 cases of patients with very large cranial defects, from a total of 156 cases, operated on in 5 Polish neurosurgical departments. The necessary implants were prepared for individual patients according to the data provided by a computed tomography examination and with the use of computer aided machining. RESULTS All defects were larger than 120 cm2 (129 to 178 cm2) and exceeded 1/4 of the calvaria area. Patients were operated between 2008 to 2012. In all patients, a very good aesthetic result and correct skull reconstruction was achieved. The follow-up time in all cases exceeded 1 year and reached 4 years in one case. No complications were observed. CONCLUSIONS Individually pre-shaped polypropylene-polyester knitwear prostheses are a good alternative to the existing cranioplasty methods, particularly in very large cranial defects.