Bone–like Polyethelyne Burr–hole Cover

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.

High Precision Bone Cutting by Er: YAG Lasers Might Minimize the Invasiveness of Navigated Brain Biopsies

Biopsies of brain tissue are sampled and examined to establish a diagnosis and to plan further treatment, e.g. for brain tumors. The neurosurgical procedure of sampling brain tissue for histologic examination is still a relatively invasive procedure that carries several disadvantages. The “proof of concept”-objective of this study is to answer the question if laser technology might be a potential tool to make brain biopsies less invasive, faster and safer. Laser technology might carry the opportunity to miniaturize the necessary burr hole and also to angulate the burr hole much more tangential in relation to the bone surface in order to take biopsies from brain regions that are usually only difficult and hazardous to access. We examined if it is possible to miniaturize the hole in the skull bone to such a high extent that potentially the laser-created canal itself may guide the biopsy needle with sufficient accuracy. The 2-dimensional, i.e. radial tolerance of the tip of biopsy needles inserted in these canals was measured under defined lateral loads which mimic mechanical forces applied by a surgeon. The canals through the skull bones were planned in angles of 90° (perpendicular) and 45° relative to the bone surface. We created a total of 33 holes with an Er : YAG laser in human skull bones. We could demonstrate that the achievable radial tolerance concerning the guidance of a biopsy needle by a laser created bone canal is within the range of the actual accuracy of a usual navigated device if the canal is at least 4 mm in length. Lateral mechanical loads applied to the biopsy needle had only minor impact on the measurable radial tolerance. Furthermore, in contrast to mechanical drilling systems, laser technology enables the creation of bone canals in pointed angles to the skull bone surface. The latter opens the perspective to sample biopsies in brain areas that are usually not or only hazardous to access.

Usefulness of Allogenic Acellular Dermal Matrix for Prevention of Scalp Depression after Burr Hole Trephination

Objective

Burr hole trephination is a common treatment for chronic subdural hematoma, intracranial hematoma, and intraventricular hematoma due to its effective drainage of hematoma, minimal invasiveness and short operation time. However, cosmetic complications such as scalp depression can occur. The aim of this study was to evaluate the usefulness of an allogenic acellular dermal matrix (ADM) to prevent scalp depression at the burr hole site.

Methods

A retrospective analysis was performed with 75 cases in 66 patients who were treated with burr hole trephination from January 2018 to December 2019. These cases divided into 2 groups; based on the method used to cover the burr hole site: Gelfoam packing only (GPO) and ADM. The degree of the scalp depression was measured from the more recent follow-up brain computed tomography scan.

Results

There was a significant difference in the degree of scalp depression between GPO and ADM groups (p=0.003). No significant correlation between patient's age and the degree of scalp depression (GPO: p=0.419, ADM: p=0.790). There were no wound infection complication in either group.

Conclusion

ADM is a suitable material to prevent scalp depression after burr hole trephination.

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.

Mineralized Collagen: Rationale, Current Status, and Clinical Applications

This paper presents a review of the rationale for the in vitro mineralization process, preparation methods, and clinical applications of mineralized collagen. The rationale for natural mineralized collagen and the related mineralization process has been investigated for decades. Based on the understanding of natural mineralized collagen and its formation process, many attempts have been made to prepare biomimetic materials that resemble natural mineralized collagen in both composition and structure. To date, a number of bone substitute materials have been developed based on the principles of mineralized collagen, and some of them have been commercialized and approved by regulatory agencies. The clinical outcomes of mineralized collagen are of significance to advance the evaluation and improvement of related medical device products. Some representative clinical cases have been reported, and there are more clinical applications and long-term follow-ups that currently being performed by many research groups.

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.

Deep brain stimulation lead fixation after Stimloc failure

We report a method for deep brain stimulation (DBS) lead fixation in the event that the primary anchoring device fails to function effectively. The method involves the application of a titanium microplate to secure the lead to the skull, thereby providing a fast and reliable "rescue" mechanism for lead fixation. This method can supplement any burr hole cap and fixation method. Furthermore, this method has several advantages over removal and replacement of the primary anchor, such as a lower possibility of lead migration, faster procedural time, and cost-effectiveness.

Medpor Craniotomy Gap Wedge Designed to Fill Small Bone Defects along Cranial Bone Flap

OBJECTIVE

Medpor porous polyethylene was used to reconstruct small bone defects (gaps and burr holes) along a craniotomy bone flap. The feasibility and cosmetic results were evaluated.

METHODS

Medpor Craniotomy Gap Wedges, V and T, were designed. The V implant is a 10 cm-long wedge strip, the cross section of which is an isosceles triangle with a 4 mm-long base, making it suitable for gaps less than 4 mm after trimming. Meanwhile, the Medpor T wedge includes a 10 mm-wide thin plate on the top surface of the Medpor V Wedge, making it suitable for gaps wider than 4 mm and burr holes. Sixty-eight pterional craniotomies and 39 superciliary approaches were performed using the implants, and the operative results were evaluated with respect to the cosmetic results and pain or tenderness related to the cranial flap.

RESULTS

The small bone defects were eliminated with less than 10 minutes additional operative time. In a physical examination, there were no considerable cosmetic problems regarding to the cranial bone defects, such as a linear depression or dimple in the forehead, anterior temporal hollow, preauricular depression, and parietal burr hole defect. Plus, no patient suffered from any infectious complications.

CONCLUSION

The Medpor Craniotomy Gap Wedge is technically easy to work with for reconstructing small bone defects, such as the bone gaps and burr holes created by a craniotomy, and produces excellent cosmetic results.

Early combined cranioplasty and programmable shunt in patients with skull bone defects and CSF-circulation disorders

OBJECTIVE

This study assesses the clinical outcome after early combined cranioplasty (own frozen bone) and shunt implantation (Codman-Medos programmable VP shunt) in patients with skull bone defects and cerebrospinal fluid (CSF) circulation disorders.

METHOD

Medical records were reviewed retrospectively for the last 100 patients with CSF disorders after trauma or subarachnoid hemorrhage (SAH), who previously underwent decompressive craniotomy owing to therapy-resistant brain swelling. Patients treated with early (5 to 7 weeks after injury) combined cranioplasty and shunt implantation were analysed and a follow-up for the survivors was obtained.

RESULTS

In 60 patients with a daily CSF external drainage over 150 ml and dilated ventricles in CT scan, a programmable VP shunt was implanted simultaneously with the cranioplasty within 5.1 weeks after decompression. The neurological condition 6 months later was good (independent patients) in 39 cases (65%); 12 patients (20%) survived with a severe disability; three patients (5%) remained in a persistent vegetative state and only six patients (10%) died. There were few complications: bone or shunt infection (three cases), post-operative intracranial bleeding (one case), transitory neurological impairment after bone reimplantation (two cases), bone resorption (two cases) and shunt dysfunction (three cases).

CONCLUSION

The early reimplantation of the patient's own skull bone combined to the employment of a programmable shunt system allowed us a dynamic adjustment of the intracranial pressure (ICP) changes. The combined treatment reduced the number of required surgical procedures, complications and unsatisfactory patient outcomes.