Comparative study between cortical bone graft versus bone dust for reconstruction of cranial burr holes

Early detection of aseptic bone necrosis post-cranioplasty: A retrospective CT analysis using Hounsfield units

This study examined the efficacy of computed tomography (CT)-based Hounsfield units (HU) as early predictors of aseptic bone necrosis, a serious post-cranioplasty complication after autologous cranioplasty. In total, 100 patients who underwent decompressive craniectomy and subsequent autologous cranioplasty were included. The radiodensity of the bone flap was evaluated in HU from CT scans at five follow-up timepoints. HU thresholds were established to predict the development of aseptic bone necrosis. HU demonstrated a declining trend throughout the follow-up period in all patients. Necrosis type I patients showed significant differences at all timepoints from 3 months post-procedure onwards, while necrosis type II patients displayed a significant decline in HU at every follow-up. Optimal thresholds with cut-off A (91.23% of initial HU) and cut-off B (78.73% of initial HU) were established to predict the occurrence of bone necrosis and the need for artificial bone replacement, respectively. Our findings demonstrated the utility of CT-based HU measurements as a simple, non-invasive tool for the early prediction of aseptic bone necrosis following autologous cranioplasty. By delineating specific HU thresholds, our study offers a valuable guide for orchestrating timely follow-ups and advising patients on the necessity of proactive interventions.

Preventing cerebral spinal fluid leakage following endoscopy through a burr hole using a novel watertight closure: technical note

BACKGROUND

Cerebrospinal fluid (CSF) leakage is a common complication after neuroendoscopic surgery through a burr hole and can lead to further complications including infection.

METHODS

We describe the use of a dural substitute larger than the burr hole itself, placed over the burr hole and then secured underneath a burr hole cover by microscrews running through the graft itself into the underlying skull.

RESULTS

This simple technical modification contributes to achieving a watertight seal to aid in preventing CSF leakage in this setting.

CONCLUSIONS

Our technical modification of endoscopy through a burr hole may help to prevent postoperative CSF leak and secondary CSF infections.

Clinical Outcomes of 3D-Printed Bioresorbable Scaffolds for Bone Tissue Engineering-A Pilot Study on 126 Patients for Burrhole Covers in Subdural Hematoma

Burrhole craniostomy is commonly performed for subdural hematoma (SDH) evacuation, but residual scalp depressions are often cosmetically suboptimal for patients. OsteoplugTM, a bioresorbable polycaprolactone burrhole cover, was introduced by the National University Hospital, Singapore, in 2006 to cover these defects, allowing osseous integration and vascular ingrowth. However, the cosmetic and safety outcomes of OsteoplugTM-C-the latest (2017) iteration, with a chamfered hole for subdural drains-remain unexplored. Data were collected from a single institution from April 2017 to March 2021. Patient-reported aesthetic outcomes (Aesthetic Numeric Analog (ANA)) and quality of life (EQ-5D-3L including Visual Analog Scale (VAS)) were assessed via telephone interviews. Clinical outcomes included SDH recurrence, postoperative infections, and drain complications. OsteoplugTM-C patients had significantly higher satisfaction and quality of life compared to those without a burrhole cover (ANA: 9 [7, 9] vs. 7 [5, 8], p = 0.019; VAS: 85 [75, 90] vs. 70 [50, 80], p = 0.021), and the absence of a burrhole cover was associated with poorer aesthetic outcomes after multivariable adjustment (adjusted OR: 4.55, 95% CI: 1.09-22.68, p = 0.047). No significant differences in other clinical outcomes were observed between OsteoplugTM-C, OsteoplugTM, or no burrhole cover. Our pilot study supports OsteoplugTM-C and its material polycaprolactone as suitable adjuncts to burrhole craniostomy, improving cosmetic outcomes while achieving comparable safety outcomes.

Craniotomy Burr Hole Covers: A Comparative Study of Biomechanical, Radiological, and Aesthetic Outcomes Using 3 Different Plug Materials

Burr holes in the cranial vault are usually made during trephination for craniotomy or drainage of chronic subdural hematomas. The resulting cranial defect might bring to unsatisfactory esthetic outcome. In the current study the authors report clinical data regarding a cohort of patients who were treated with 3 different types of burr hole covers; autologous bone dust from skull trephination, and 2 different types of cylindric plug made out of porous hydroxyapatite in order to evaluate medium and long-term esthetic and radiological outcomes. Twenty patients were consecutively enrolled in the study and in each patient all 3 types of materials were used to cover different holes. Clinical and radiological outcomes at 6 and 12 months, were analyzed for all 3 types of plugs in terms of thickness of the graft coaptation of margins, remodeling, fractures, mobilization, and contour irregularities. In all craniotomy holes filled with autologous bone dust the authors have observed partial or complete bone reabsorption at 1 year and in 60% of the cases a visible and palpable cranial vault contour irregularity was reported. Both types of bone substitutes gave satisfactory results, comparable to autologous bone dust at 6 months and superior at 12 months, especially in terms of thickness and esthetic appearance. Hydroxyapatite plugs have shown better esthetic and biomechanical results and higher patients' satisfaction compared to autologous bone dust while not giving any additional complications.

The Helmet-Visor Pericranial Flap as a Viable Option for Anterior Cranial Base Reconstruction in Complex Oncologic Cases

OBJECTIVE

To describe a novel bilaterally pedicled pericranial flap for anterior cranial base reconstruction after removal of complex frontobasal cancers extending to the frontal region, thus precluding the use of standard reconstructive techniques.

METHODS

In selected oncologic cranial base surgeries, the use of the standard galea frontalis pericranial flap for reconstructive purposes may be precluded by tumor infiltration. In such cases, dura mater reconstruction and exclusion of frontal sinuses from the intracranial space can be performed using a large superficial temporal artery bilaterally pedicled pericranial flap obtained from both temporoparietal regions. Surgical technique, indication, contraindication, complications, and degree of resection are recorded to evaluate the efficacy of this surgical method.

RESULTS

A 48-year-old man affected by a recurrence of frontobasal squamous cell carcinoma was surgically treated by combined transcranial and endoscopic endonasal resection. A large pericranial flap pedicled bilaterally on the parietal branches of the superficial temporal artery was obtained, transposed anteriorly, carefully watertight sutured to the dural defect, and used to exclude cranialized frontal sinuses as well. The reconstruction was successful, and the patient was discharged home on the tenth postoperative day without any complications and/or development of cerebrospinal fluid leak. Contrast-enhanced magnetic resonance imaging 3 months after surgery was clear from disease with consolidated surgical outcomes.

CONCLUSIONS

This novel pericranial flap seems to be easily obtained and effective for anterior cranial base reconstruction when the use of a traditional galea frontalis flap is precluded for oncologic reasons and there are concerns for the possible development of contaminations and cerebrospinal fluid leaks.

Long-term follow-up for ossification of autologous bone plug and skin sinking after periosteum-preserved burr hole surgery

Background:

The demand of a burr hole surgery for chronic subdural hematoma (CSDH) is increasing in the global aging society. Burr hole-derived autologous bone dusts are not associated with extra costs compared with other commonly used synthetic materials. In addition, postoperative calvarium ossification requires periosteum-mediated blood supply, which is lacking after using avascular synthetic materials. Based on these findings, we hypothesized that the combination of the bone plugs and the preserved periosteum during burr hole surgeries for CSDH would induce efficient calvarium ossification.

Methods:

We evaluated the long-term effects of bone plugs on the degree of ossification and cosmetic appearance of the skin covering the burr hole sites. We included 8 patients (9 burr holes) who received the autologous bone dust derived from burr holes. As the control group, 9 burr holes that did not receive any burr hole plugs were retrospectively selected. These burr holes were evaluated by computed tomography (CT) scan for the calvarium defect ratios, CT value-based ossification, and the degree of skin sinking.

Results:

Ossification was observed in all the bone plugs by the bone density CT scans; they maintained their volume at 12 months after the surgeries. The calvarium defect ratios (volume ratios of the unossified parts in the burr holes) gradually increased during the first 6 months and reached 0.44 at 12 months. The mean CT values also increased from 527 HU to 750 HU for the first 6 months and reached 905 HU at 12 months. The degrees of skin sinking at the burr hole sites with the bone plugs were 1.24 mm whereas those without the bone plugs were 2.69 mm (P = 0.004).

Conclusion:

Application of burr hole-derived autologous bone dust is associated with better ossification and objective cosmetic result following burr hole surgery after CSDH.

Advantages of Calvarial Vault Distraction for the Late Treatment of Cephalocranial Disproportion

PURPOSE

Cephalocranial disproportion is a symptomatic condition related to a volume discrepancy between the calvarial vault and the brain. Traditional expansion techniques are unfavorable in older children due to inadequate dural ossification, lack of bone pliability, and limited future growth potential. The authors review their experience using distraction to close bone defects in this setting.

METHODS

A retrospective analysis was performed of all patients treated using distraction in this setting by a single surgeon. Demographic and outcomes data were collected. The efficacy of ossification of bone defects after expansion by distraction was measured using volume analysis of three-dimensional computed tomography (CT) scans. This required a CT scan at the completion of device activation and a follow-up CT scan 6 months or more beyond activation.

RESULTS

Sixteen patients (17 distractions) met the imaging-based inclusion criteria. The average age at surgery was 3.97 (2.14-6.89) years. The mean initial bone defect volume after asymmetric transverse distraction was 7.26 (5.45-13.73) mL. The mean final defect volume was 2.18 (0.00-5.90) mL with a mean change of 5.08 (1.21-12.79) mL and mean interval time of 27.85 (7.13-56.39) months. This represents a mean percent defect closure of 72.30 (20.38-100.00).

CONCLUSION

Distraction osteogenesis is a very effective tool for treating the older child with cephalocranial disproportion. The ability to ossify the bone defects without a donor site provides a considerable advantage in these patients.

Biodegradable Mineralized Collagen Plug for the Reconstruction of Craniotomy Burr-Holes: A Report of Three Cases

Objectives

In this case report, we describe the design, fabrication and clinical outcomes of a novel bioresorbable, mineralized collagen burr-hole plug for the reconstruction of craniotomy burr-holes.

Methods

Mineralized collagen burr-hole plugs were fabricated via a biomimetic mineralization process. The biomimetic mineralized collagen has a similar chemical composition and microstructure to natural bone tissue, thereby possessing good biocompatibility and osteoconductivity. The mineralized collagen burr-hole plugs were implanted into three patients, and clinical outcomes were evaluated at one-year follow-ups.

Results

All bone defects healed very well using the mineralized collagen burr-hole plugs, and there were no adverse reactions at the surgical sites.

Conclusions

The clinical outcomes indicated that the mineralized collagen was effective for reconstructing burr-holes in the skull after craniotomy.

The Efficacy of Titanium Burr Hole Cover for Reconstruction of Skull Defect after Burr Hole Trephination of Chronic Subdural Hematoma

OBJECTIVE

Although burr hole trephination is a safe and effective surgical option to treat patients with chronic subdural hematoma (CSDH), it often results in a small but undesirable scalp depression from burr hole defect. This study is to evaluate the efficacy of titanium burr hole cover (BHC) for reconstruction of skull defects in these patients.

METHODS

A hundred and ninety-six cases of burr hole trephinations for CSDHs between January 2009 and December 2013 were assigned into two groups; Gelfoam packing only (GPO) and reconstruction using titanium BHC group, according to the modalities of burr hole reconstructions. The incidences and depths of scalp depressions and incidences of postoperative complications such as infections or instrument failures were analyzed in both groups. We also conducted telephone surveys to evaluate the cosmetic and functional outcomes from patient's aspect.

RESULTS

Significantly lower incidence (p<0.0001) and smaller mean depth (p<0.0001) of scalp depressions were observed in BHC than GPO group. No statistical differences were seen in postoperative infection rates (p=0.498) between the two groups. There were no instrument failures in BHC group. According to the telephone surveys, 73.9% of respondents with scalp depressions had cosmetic inferiority complexes and 62.3% experienced functional handicaps during activities of daily life.

CONCLUSION

Titanium BHC is highly effective for reconstruction of skull defect after burr hole trephination of CSDH, and provides excellent cosmetic and functional outcomes without significant complications.

Comparison of bone dust with other types of bone grafts for cranioplasty

PURPOSE

Split calvarial bone graft is preferred in the reconstruction of calvarial defects. However, it is not feasible for use in some challenging cases and in children. Particulate bone graft containing viable osteoblasts could be an attractive alternative.

MATERIALS AND METHODS

A total of 32 female rats were randomly separated into 4 groups. Full-thickness bone graft from rat calvaria was harvested in diameters of 8 × 8 mm. In group 1, the periosteum and skin were closed without any bone graft; bone dust particles were placed in group 2; bone fragments were placed in group 3; and full-thickness cranial bone graft was placed in group 4. After 12 weeks, all rats were killed. Degrees of resorption, foreign body reaction, and bone spicule length were assessed histologically, and an immunohistochemical study was used to show bone graft viability.

RESULTS

In graft viability, osteogenesis, and osteoblastic differentiation, groups 3 and 4 were similar and superior to groups 1 and 2. No osteoblastic activity and no viable bone dust were detected in groups 1 and 2. Resorption was observed in every preparate that contains bone tissue, and foreign body reaction was prominent in small bone groups, such as in group 2.

CONCLUSIONS

In the full-thickness cranial bone graft group and the bone fragment group, the preservation of bone viability was obviously superior to the bone dust group and the periosteum-only group. In conclusion, bone dust behaved like the periosteum and could not create new bone, whereas bone particles behaved like the full-thickness cranial bone graft and were capable of preserving viability.