Titanium Mesh Implant Exposure Due To Pressure Gradient Fluctuation

• Published in: World neurosurgery 2018-11, Vol.119, p.e734-e739
• Main Authors: Yoshioka, Nobutaka, Tominaga, Shinsuke
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Brain Infarction - surgery; Brain Neoplasms - surgery; Cerebral Hemorrhage - surgery; Complication; Cranioplasty; Craniotomy - instrumentation; Craniotomy - methods; Female; Hematoma, Subdural, Acute - surgery; Humans; Implant exposure; Intracranial Arteriovenous Malformations - surgery; Male; Mechanism; Middle Aged; Preoperative Care - methods; Pressure; Pressure gradient; Prostheses and Implants - adverse effects; Prosthesis Failure - adverse effects; Surgical Mesh; Titanium - adverse effects; Titanium mesh exposure; Tomography, X-Ray Computed
• ISSN: 1878-8750; 1878-8769
• DOI: 10.1016/j.wneu.2018.07.255

Titanium mesh implants (TMIs) are used for various purposes in craniotomy. Although delayed implant exposure and thinning of the overlying skin are well-known complications, the mechanism has not yet been elucidated. We reviewed our cases and propose a mechanism for TMI exposure. From 2009 to 2018, we treated 14 patients with delayed titanium implant exposure after craniotomy. The exposed titanium implant was a TMI in 4 patients, a titanium mesh plate in 6 patients, and a titanium fixation plate with holes in 4 patients. We reviewed the preoperative computed tomography (CT) scans and operative findings. The interval between craniotomy and implant exposure was 13 years (range, 5–27). Implant exposure occurred at the temporal region in 7 patients, frontal region in 6 patients, and parietal region in 1 patient. The skin ulcer size ranged from 0.25 to 10 cm2 (mean, 1.95). In the patients with TMI exposure, the dura was expanded, and no residual epidural space was identified on the CT scans; however, epidural dead space was revealed on the CT scan in the patients with titanium mesh plate or titanium fixation plate exposure. We believe that the key factor resulting in delayed titanium mesh exposure is the pressure gradient between the atmosphere and the intracranial space. Fluctuation of this gradient exerts dynamic stress on the tissue in the mesh holes and the adjacent tissue, resulting in tissue damage and implant exposure. •TMIs have the potential risk of overlying skin thinning and delayed exposure.•Radiation and aging cause skin thinning; however, the question remains whether these factors will result in implant exposure.•Epidural dead space is not always found in patients with titanium mesh implant exposure.•We have proposed a mechanism for implant exposure from our experience.