Long-term Effect of Cranioplasty on Overlying Scalp Atrophy

Cranioplasty With Hydroxyapatite Implants: A Multidisciplinary Approach of Neurosurgeon and Plastic Surgeons to Improve Surgical Technique and Clinical Outcome

Cranioplasty using Hydroxyapatite prosthesis is a conceptually simple procedure, but it may harbor several challenges for the surgeons. Several papers in the literature deal with cranioplasty using porous hydroxyapatite. The results are not homogeneous both because of the variability of the patients treated but also because Hydroxyapatite requires a more careful surgical technique to achieve maximum performance. The aim of the present study is to offer an insight of a single institution, multidisciplinary experience with custom-made Hydroxyapatite cranioplasty with surgical tips and tricks based on personal opinion and literature evidence. We will provide an overview of all the fundamental steps we believe to be useful to optimize surgical outcomes, including preoperative planning of cranioplasty; as cranioplasty flap/soft tissue coverage planning, infectious prophylaxis, patient positioning, incisional patterns, tissue dissection, primary bone demolition, and preparation of the craniectomy margins before implant positioning. The authors will also discuss methods for dural suspension, implant fixation and anchorage, margins polishing, drainage, suturing, and dressing. Cranioplasty using hydroxyapatite prosthesis is a valuable alternative for skull reconstruction with heterologous implants, and in our opinion a multidisciplinary approach integrating plastic surgeons and neurosurgeons' specific skills can facilitate surgical planning, reducing complications and allowing to achieve better functional and aesthetic results.

The role of autologous bone in cranioplasty. A systematic review of complications and risk factors by using stored bone

BACKGROUND

Autologous bone cranioplasty is associated with a high complication rate, particularly infections and bone resorption. Although there are studies on the incidence and risk factors for complications following autologous bone cranioplasty, the study design is typically limited to retrospective analysis with multiple statistical explorations in small cohorts from single centers. Thus, there is a need for systematic analysis of aggregated data to determine the rate and risk factors for cranioplasty complications.

OBJECTIVE

To determine the incidence and risk factors for complications after autologous bone cranioplasty.

METHODS

In this systemic review, we conducted a Medline, Embase, Cochrane, and Web of Science search: 11,172 papers were identified. Duplicates were removed and only articles on complications following autologous bone cranioplasty between the years 2000 and 2022 were included. After title, abstract, and article screening, 132 papers were included for further analysis.

RESULTS

In total, the 132 studies are based on 13,592 patients (14960 implants). One third of the studies include patients with less than 3 months of postoperative follow-up. Complication management (flap removal, revision without flap removal, and conservative treatment) of infection, bone resorption, and hematoma/seromas are not reported in 19-30% of the studies. In the studies with defined complications management, the overall complication rate is 7.6% (95% Confidence Interval (CI) [7.1-8.2]) for infection, 14.4% (95% CI [13.7-15.2]) for bone resorption with indication for reconstruction, and 5.8%, (95% CI 5.2-6.5) for hematoma/seromas. Factors such as younger age, an extended interval between craniectomy and cranioplasty, the use of a fragmented bone implant, a larger implant size, and shunt treatment are linked to an increased risk of postoperative bone resorption.

CONCLUSION

The lack of consistent definitions of complications, variations in follow-up time, and small study cohorts limit the external validity of many studies. Overall, the rate of bone flap resorption that required reoperation is high, while the rate of infectious complications is comparable to synthetic implants. Thus, autologous bone should preferably be used in cases without strong risk factors for bone necrosis.

Challenging frontiers in neuroplastic cranial reconstruction: addressing neurosurgical wound healing complications through interdisciplinary collaboration - an observational study

BACKGROUND AND OBJECTIVES

Although rare, complications like skin dehiscence and necrosis after neurosurgery pose significant challenges by increasing the risk of infections spreading to the epidural, subdural, or intracerebral spaces. This retrospective, single-center study aims to assess the prior clinical courses, neuroplastic repair, and outcomes of  patients with skin defects following cranial neurosurgical procedures, and to outline our interdisciplinary reconstructive protocol.

METHODS

A retrospective analysis was performed on cranial surgeries conducted at the Department of Neurosurgery,  spanning from 2017 to 2023. Patients with skin defects requiring the combined expertise of neurosurgery and plastic surgery for effective treatment were included. The sizes of the skin defects were measured using intraoperative photographs analyzed with the freeware ImageJ software, version 2018. All patients provided informed consent for the surgeries. If informed consent was not possible due to neurological deterioration, consent was sought from adult representatives or next of kin except for acute circumstances. All patients admitted to our hospital agree to the pseudonymized use of their medical data and tissue specimens for research purposes in their treatment contract.

RESULTS

A cohort of 24 patients experiencing wound healing complications after neurosurgical procedures underwent a total of 29 interdisciplinary surgeries for the reconstruction of skin, dural, and bone defects.  After the neuroplastic surgery, 8 out of 24 patients (33.3%) developed surgical complications, with 6 of these requiring revision surgeries due to persistent cranial infection.  In all cases,  permanent wound closure was successfully achieved following adherence to the proposed treatment algorithm.

CONCLUSIONS

Our study underscores the necessity of an integrated neurosurgical and plastic surgical approach to effectively manage wound healing complications in a single stage surgery. Key interventions include differentiation between necrosis and gaping lesions, alongside precise management of neurosurgical issues like cerebrospinal fluid fistulas and hydrocephalus. Plastic surgical expertise in assessing the possibilities and limitations of both local and free flap surgeries is essential.

Role of Plastic Surgery in the Treatment of Titanium Mesh Exposure Following Cranioplasty

BACKGROUND

Titanium mesh cranioplasty is the most common strategy for the repair of skull defects. However, as the frequency of cranioplasty increases, the incidence of titanium mesh exposure following cranioplasty increases as well. This study aimed to investigate the methods and outcomes of plastic surgery in the management of titanium mesh exposure following cranioplasty.

METHODS

Patients with titanium mesh exposure following cranioplasty were retrospectively selected from January 2016 to August 2021. Titanium mesh exposure was corrected with reconstructive plastic surgery, including skin grafting, expander insertion, partial removal of the exposed mesh, replacement of the mesh, or flap transplantation.

RESULTS

This study included 21 patients with titanium mesh exposure with surgical site infection and a variant of scalp deformity. The age of the patients ranged from 18 to 74 years, with the mean age being 54 years. All patients underwent reconstructive plastic surgery and exhibited complete wound healing. The follow-up period ranged from 17 to 90 months. One patient experienced titanium mesh re-exposure and subsequently underwent an additional procedure for the partial removal of the exposed mesh. No serious complications were observed postoperatively.

CONCLUSION

Reconstructive plastic surgery can facilitate wound healing at the titanium mesh exposure site following cranioplasty. However, an individualized treatment strategy is required for each patient, and complications should be managed by adopting standard measures.

A Comparative Study of Titanium Cranioplasty for Extensive Calvarial Bone Defects: Three-Dimensionally Printed Titanium Implants Versus Premolded Titanium Mesh

OBJECTIVE

This study compared the complications and symmetry outcomes between 3-dimensionally printed titanium implants and premolded titanium mesh in patients with extensive calvarial bone defects.

METHODS

This retrospective analysis included patients with calvarial defects >50 cm2 undergoing cranioplasty who received either a 3-dimensionally printed titanium implant manufactured by selective laser melting techniques (N = 12) or a premolded titanium mesh customized onto a 3-dimensionally printed skull template (N = 23). Complications including intracranial infection, hardware extrusion, wound dehiscence, and cerebrospinal fluid leaks were investigated. Predictive factors affecting complications were investigated to identify the odds ratios in univariate and multivariate analyses. The symmetry was assessed by calculating the root mean square deviation, which showed the morphological deviation of the selected area compared with the mirrored image of the contralateral region.

RESULTS

The overall complication rate was 26.1% (6/23 patients) in the premolded titanium group and 16.7% (2/12 patients) in the 3-dimensionally printed group. The reoperation rates did not differ significantly between the 2 groups (3-dimensionally printed group, 16.7%, versus premolded group, 21.7%). In multivariate analysis, only the number of previous cranial operation was significantly associated with the complication rate (odds ratio, 2.42; 95% confidence interval, 1.037-5.649; P = 0.041). The mean ± SD of the root mean square deviation was significantly smaller in the 3-dimensionally printed group (2.58 ± 0.93 versus 4.82 ± 1.31 mm, P < 0.001).

CONCLUSIONS

The 3-dimensionally printed titanium implant manufactured by the selective laser melting technique showed comparable stability and improved symmetry outcomes compared with the conventional titanium mesh in the reconstruction of extensive calvarial defects.

Full-thickness skin regeneration beneath the exposed titanium mesh in cranioplasty: Two cases report

RATIONALE

Titanium mesh is one of the most widely used implant materials applied in cranioplasty; however, it has been reported to encounter the risk of progressive scalp thinning and implant exposure over time. Here we present 2 cases of exposed titanium mesh (TM) and unusual phenomena of full-thickness skin regeneration beneath the mesh.

PATIENT CONCERNS

Two patients, 1 with an 8-year and 1 with a 2-year history of implant exposure after cranial TM implantation.

DIAGNOSES

The patients were diagnosed with scalp ulcers and cranial TM exposure.

INTERVENTION

The exposed part of the implant was removed, and the full-thickness skin beneath the mesh was directly used as functional soft tissue coverage to repair the scalp defect.

OUTCOMES

Full recovery for both patients with cosmetic satisfaction.

LESSONS

Though the exact mechanism of this epithelisation phenomenon beneath the TM remains to be elucidated, it provided a feasible choice for clinicians to reconstruct the scalp's integrity without exerting complicated procedures when dealing with similar cases.

Scalp complications of craniofacial surgery: classification, prevention, and initial approach: an updated review

Background

Scalp complications in craniofacial surgeries can increase morbidity and mortality. Given the inelastic characteristics of the scalp, these surgeries can be challenging, and multiple complications can arise. The literature on craniofacial surgery is extensive. However, few articles address scalp complications, associated factors, and prevention. This study aims to identify and classify scalp complications in craniofacial surgery and describe associated risk factors, general preventive measures, and an initial therapeutic approach.

Methods

We conducted a literature search in PubMed, Scopus, Cochrane Library, and LILACS to review the scalp complications in craniofacial surgery. The studies selected included retrospective case series, narrative reviews, systematic reviews, and cadaveric anatomic studies. We completed the search with book chapters and specific topic reviews.

Results

We screened a total of 124 sources and selected 35 items for inclusion in this review. Based on the updated review, we categorized scalp complications into wound defects, soft tissue contour irregularities, neurovascular defects, and infection. We discuss the main characteristics, risk factors, preventive measures, and initial management of these complications.

Conclusions

For craniofacial surgery, understanding the surgical anatomy, identifying risk factors, adequate surgical planning, and interdisciplinary cooperation between neurosurgeons, plastic surgeons, and the interdisciplinary team are essential to prevent and treat scalp complications.

Level of evidence: Not ratable