gms | German Medical Science

Objective: The decompressive craniotomy is considered to be an approved surgical concept for brain swelling due to traumatic, hemorrhagic or ischaemic causes. The results of a survey in German neurosurgical hospitals proved that 65% preserve autologous bone flap, 85% of them use deep freezers and other 13% the patients’ abdomen. Constrained by practical experience, intricacies and a new German legislation, which increase costs and complexity of extracorporal bone storage, we took up an until now rarely described method of bone flap preservation under the galea aponeurotica – called “convertible – technique”.

Methods: During the last year a decompressive craniotomy was indicated (causes: trauma=5, ICB=4, stroke=3) in 12 patients (♀=5, ♂=7). Depending on the anatomical conditions, we sawed a bone flap above the affected hemisphere and created a subgaleal pocket towards the contralateral side as large as possible. In addition to placing the bone in the new cavity by utilising both convexities, we closed the skin with a loose skin closure. Replantation was performed 4-6 months after decompression. After opening the old wound, the bone flap was mobilized and turned back into the original location, being fixed with metal blanks.

Results: The average size of the displaced bone flaps has been 13x9 cms (length max./min.: 15/10cms - width max./min.: 10/8cms). The mean additional time for special preparing added up to 15min (max./min.: 10/20min). In the postoperative phase no complications such as inadequate space, skin necrosis, infection or bone alterations have been observed.

Conclusions: The “convertible – technique” seems to us to be a practicable, uncomplicated and cost-saving method, which combines low perioperative risk, the advantages of the autologous bone material and a high level of sterile handling. Especially the limitation to one wound area reduces the risk of infection and makes other operative procedures in the abdomen possible. In view of the new German “tissue-law”, the described technique avoids expensive and sophisticated procedures in pre-processing of autologous bone material.