Porous polyethylene implant for cranioplasty and skull base reconstruction

Nasoseptal flap and rigid reconstruction in endoscopic endonasal skull base surgeries: The longitudinal experience of a single center

BACKGROUND

Recently, endoscopic endonasal approaches (EEA) have been used for skull base defect reconstruction surgeries. The nasoseptal flap (NSF), a vascular pedicled flap, was introduced to decrease postoperative cerebrospinal fluid (CSF) leakage.

PURPOSES

This study aimed to outline the authors' institutional experience using NSF and rigid implants in anterior skull base defect reconstruction surgeries following EEA.

DESIGN

A retrospective cohort review of patients who underwent NSF reconstruction following EEA in the Otorhinolaryngology and Neurosurgery Departments at King Saud University Medical City, Riyadh, Saudi Arabia, from January 2015 to May 2021, divided into 2 time periods according to the reconstruction technique.

RESULT

Out of the 106 patients who underwent EEA, 77 underwent NSF reconstruction. The majority had expanded EEA (94.8%). The mean age was 40.21 ± 17.7 years, and the female gender represented 61% of the sample. More than half of the sample underwent right NSF (57.1%). Meningioma was the most common diagnosis (45.5%). The clivus was the most frequent site of lesions (23.4%). The overall rate of postoperative CSF leakage and lumbar drainage (LD) insertion was 15.6% and 51.9%, respectively. The duration of LD was a median of four days. The overall failure rate was 13%, declining from 20% in the first period to 5.4% in the second period. Rigid implants were used significantly more in the first period than in the second period (67.5% versus 16.2%, P < 0.001). Meningitis, the highest postoperative complication, was reported in 6 patients (7.8%). One patient died three weeks postoperatively after massive nasal bleeding. No significant difference was found between either side of the NFS regarding the CSF leakage and failure rate.

CONCLUSION

In the authors' experience, there has been an overt decline in failure rates and complications of EEA over the last three years due to increased experience among surgeons and a standardization of reconstruction techniques. Minimal reconstruction may provide satisfactory results by decreasing the use of rigid implants. An endoscopic endonasal approach with an NSF for anterior skull base defect reconstruction is considered a safe procedure with no significant difference between the sides of the flap.

Bifrontal Osteoplastic Flap: An Option to Decrease Infection in Bifrontal Craniotomies with Skull Base Osteotomies

Infection can be a common complication following bifrontal craniotomy with skull base osteotomies given the potential violation of sinuses and entry into the nasal structures. Our objective was to examine our series of patients who underwent a bifrontal craniotomy with skull base osteotomies and describe the infection rate. We propose the bifrontal osteoplastic flap as an adjunct to infection prevention. A retrospective single-center study of a patient database was performed. Twenty patients were identified. Fifty-five percent were male. The mean age was 55.7 ± 13.9 years. The most common indications for surgery were esthesioneuroblastomas (35%) and anterior skull base meningiomas (30%). Six patients (30%) developed an infection, 1 patient (5%) developed a CSF leak, and no patients developed a mucocele. All 6 infected cases had nasal pathology with intracranial extension, they all received chemoradiation post-operatively and were all combined cases with otorhinolaryngology. Eighty-three percent of these patients required a craniectomy and all of them required long-term IV antibiotics. Infection is not uncommon after a bifrontal craniotomy with skull base osteotomies and the use of the bifrontal osteoplastic flap in cases where the risk of infection is high, i.e., esthesioneuroblastomas surgery, may help reduce said risk and lead to better patient outcomes.

Prevalence of Postoperative Complications of Autologous and Heterologous Cranioplasty in the Pediatric Population: A Systematic Review of the Literature

INTRODUCTION

Cranial reconstruction (CR) is a neurosurgical procedure performed to restore the cranial vault after a decompressive craniectomy. There are contrasting reports from the literature about the complications related to the use of heterologous materials for CR in the pediatric population. In this study, the authors try to better define such a rate of adverse events for autologous and heterologous materials.

MATERIALS AND METHODS

A systematic review of articles published up to December 2021 was performed. Studies were included if they reported the specific use of cranioplasty materials following craniectomy in patients younger than 18 years of age and had a minimum follow-up of at least 1 year.

RESULTS

A total of 20 studies were selected. A total of 544 cases were included, of which 422 (77.6%) were with heterologous materials and 122 (22.4%) with autologous bone. The mean average age was 9.5 years. Polyetheretherketone and polymethylmethacrylate reported 29% and 33.3%, respectively, of complications, but only 3% and 5.6% of surgical revision. PHA reported a rate of 11.9%. Titanium reported 9.2% of complications and 4.1% of surgical revisions. Porous polyethylene had a complication rate of 36.4% and a revision rate of 0%.

CONCLUSION

There is still no perfect material for CR. It seems that heterologous materials are superior to autologous bone for CR in children, and we may consider, whenever economic conditions will allow it, to use alloplastic material as first-line in small children.

State-of-Art of Standard and Innovative Materials Used in Cranioplasty

Cranioplasty is the surgical technology employed to repair a traumatic head injury, cerebrovascular disease, oncology resection and congenital anomalies. Actually, different bone substitutes are used, either derived from biological products such as hydroxyapatite and demineralized bone matrix or synthetic ones such as sulfate or phosphate ceramics and polymer-based substitutes. Considering that the choice of the best material for cranioplasty is controversial, linked to the best operation procedure, the intent of this review was to report the outcome of research conducted on materials used for such applications, comparing the most used materials. The most interesting challenge is to preserve the mechanical properties while improving the bioactivity, porosity, biocompatibility, antibacterial properties, lowering thickness and costs. Among polymer materials, polymethylmethacrylate and polyetheretherketone are the most motivating, due to their biocompatibility, rigidity and toughness. Other biomaterials, with ecofriendly attributes, such as polycaprolactone and polylactic acid have been investigated, due to their microstructure that mimic the trabecular bone, encouraging vascularization and cell-cell communications. Taking into consideration that each material must be selected for specific clinical use, the main limitation remains the defects and the lack of vascularization, consequently porous synthetic substitutes could be an interesting way to support a faster and wider vascularization, with the aim to improve patient prognosis.

Outcomes and complications associated with malar onlays: literature review and case series of 119 implants

Alloplastic malar onlays have been used by surgeons to correct or enhance the midfacial skeleton for over 40 years. Case series have shown respectable results using different alloplastic materials in various maxillofacial subsites. However, these articles include small numbers of patients with limited follow up. We present a literature review specifically concentrating on porous polyethylene (Medpor, Stryker) and polyethyl ether ketone (PEEK) malar onlays. We illustrate the technique used by a single oral and maxillofacial surgeon for placement of 119 implants in 61 patients over a 14-year period, and show the results of this work with long-term follow up. A complication rate of 2.5% in this cohort was reported, with follow up of three years, demonstrating that this technique for midfacial correction is successful in both the short and the long term.

Evaluation of tissue ingrowth and reaction of a porous polyethylene block as an onlay bone graft in rabbit posterior mandible

Purpose

A new form of porous polyethylene, characterized by higher porosity and pore interconnectivity, was developed for use as a tissue-integrated implant. This study evaluated the effectiveness of porous polyethylene blocks used as an onlay bone graft in rabbit mandible in terms of tissue reaction, bone ingrowth, fibrovascularization, and graft-bone interfacial integrity.

Methods

Twelve New Zealand white rabbits were randomized into 3 treatment groups according to the study period (4, 12, or 24 weeks). Cylindrical specimens measuring 5 mm in diameter and 4.5 mm in thickness were placed directly on the body of the mandible without bone bed decortication, fixed in place with a titanium screw, and covered with a collagen membrane. Histologic and histomorphometric analyses were done using hematoxylin and eosin-stained bone slices. Interfacial shear strength was tested to quantify graft-bone interfacial integrity.

Results

The porous polyethylene graft was observed to integrate with the mandibular bone and exhibited tissue-bridge connections. At all postoperative time points, it was noted that the host tissues had grown deep into the pores of the porous polyethylene in the direction from the interface to the center of the graft. Both fibrovascular tissue and bone were found within the pores, but most bone ingrowth was observed at the graft-mandibular bone interface. Bone ingrowth depth and interfacial shear strength were in the range of 2.76-3.89 mm and 1.11-1.43 MPa, respectively. No significant differences among post-implantation time points were found for tissue ingrowth percentage and interfacial shear strength (P>0.05).

Conclusions

Within the limits of the study, the present study revealed that the new porous polyethylene did not provoke any adverse systemic reactions. The material promoted fibrovascularization and displayed osteoconductive and osteogenic properties within and outside the contact interface. Stable interfacial integration between the graft and bone also took place.

Transclival approaches for intradural pathologies: historical overview and present scenario

Recently, endoscopic transsphenoidal transclival approaches have been developed and their role is widely accepted for extradural pathologies. Their application to intradural pathologies is still debated, but is undoubtedly increasing. In the past five decades, different authors have reported various extracranial, anterior transclival approaches for intradural pathologies. The aim of this review is to provide a historical overview of transclival approaches applied to intradural pathologies. PubMed was searched in October 2018 using the terms transcliv*, cliv* intradural, transsphenoidal transcliv*, transoral transcliv*, transcervical transcliv*, transsphenoidal brainstem, and transoral brainstem. Exclusion criteria included not reporting reconstruction technique, anatomical studies, reviews without new data, and transcranial approaches. Ninety-one studies were included in the systematic review. Since 1966, transcervical, transoral, transsphenoidal microsurgical, and, recently, endoscopic routes have been used as a corridor for transclival approaches to treat intradural pathologies. Each approach presents a curve that follows Scott's parabola, with evident phases of enthusiasm that quickly faded, possibly due to high post-operative CSF leak rates and other complications. It is evident that the introduction of the endoscope has led to a significant increase in reports of transclival approaches for intradural pathologies. Various reconstruction techniques and materials have been used, although rates of CSF leak remain relatively high. Transclival approaches for intradural pathologies have a long history. We are now in a new era of interest, but achieving effective dural and skull base reconstruction must still be definitively addressed, possibly with the use of newly available technologies.

Pediatric Cranioplasty

Historically, the approach to pediatric cranioplasty has been largely extrapolated from the treatment of adults. More recently, however, the intricacies of pediatric cranial reconstruction have become better understood, and the surgical management has been refined contemporaneously. Each patient's cranial defect bears a unique set of challenges and, as such, the choice of cranioplasty technique must be tailored accordingly.

Development of Chronic Sphenoid Sinusitis After Sellar Reconstruction with Medpor Porous Polyethylene Implant

OBJECTIVE

The Medpor porous polyethylene implant is reported to be safe and effective for sellar reconstruction after transsphenoidal surgery (TSS). However, we have observed several cases of delayed chronic sphenoid sinusitis related to the implant. The purpose of this study is to describe the presentation and management of implant-related sphenoid sinusitis after sellar reconstruction.

METHODS

This is a retrospective study of patients who underwent endonasal TSS with Medpor sellar reconstruction between December 2008 and January 2013 at a tertiary care institution. Patient demographics, initial surgical management, sinonasal symptoms, postoperative imaging, sinusitis management, and resulting outcomes were analyzed.

RESULTS

From 2008-2013, 139 patients underwent sellar reconstruction using Medpor. Five patients (3.6%) presented between 8 and 60 months after surgery with chronic sphenoid sinusitis that required surgical management. All 5 patients presented as outpatients for management of headaches and nasal drainage, 4 patients experienced chronic nasal congestion, and 3 patients noted recurrent sinusitis. At the time of revision surgery, all 5 patients were found to have mucosal inflammation and edema surrounding the implant, and 4 of the 5 had an exposed or partially extruded implant that was removed.

CONCLUSIONS

Reconstruction of the sellar floor may be performed after TSS to prevent postoperative complications. Although porous polyethylene implants have previously been described as safe and effective for this purpose, surgeons should be aware of the risk of subsequent implant extrusion and chronic sphenoid sinusitis that can occur in a delayed manner.

Cosmetic Reconstruction of Frontotemporal Depression Using Polyethylene Implant after Pterional Craniotomy

Purpose

Pterional craniotomy is a useful approach for the treatment of a variety of intracranial pathologies. However, it can result in temporal hollowing, which causes significant craniomaxillofacial asymmetry and esthetic deformity. The present study was performed to determine the postoperative outcomes of patients following frontotemporal depression reconstruction using a high-density porous polyethylene (HDPE) implant (Medpor®; Stryker, Kalamazoo, MI) after pterional craniotomy.

Materials and Methods

The patients had undergone reconstruction of frontotemporal depression using Medpor® implants after pterional craniotomy at our medical institution during the period from February 2010 to March 2014. We evaluated the thickness and volume of both the temporalis muscle and Medpor® implant through a retrospective review of the medical records and computed tomography (CT) scans of 92 patients.

Results

The mean temporalis muscle thickness ratio (muscle thickness of the affected side/nonaffected side) was 0.61 ± 0.16. The mean reconstructed temporalis muscle thickness ratio (muscle and Medpor® implant thickness of affected side/muscle thickness of nonaffected side) was 1.15 ± 0.02. The mean temporalis muscle volume ratio (muscle volume of affected side/nonaffected side) was 0.67 ± 0.02. The mean reconstructed temporalis muscle volume ratio (muscle and Medpor® implant volume of affected side/muscle volume of nonaffected side) was 1.18 ± 0.02.

Conclusions

Temporalis muscle thickness and volume were significantly decreased on the affected side after pterional craniotomy. Reconstruction of frontotemporal lesions using Medpor® implants after the pterional approach improved temporal hollowing without additional complications.

Cranioplasty

Cranioplasty following craniectomy for trauma is a common, safe neurosurgical procedure that restores the natural cosmesis and protective barrier of the skull and may be instrumental in normalizing cerebrospinal fluid dynamics after decompressive surgery. Understanding the factors influencing patient selection and timing of cranioplasty, the available materials and methods of skull reconstruction, and the technical nuances is critical for a successful outcome. Neurosurgeons must be prepared to manage the complications specific to this operation. This article reviews the indications, preoperative assessment and timing, most commonly used materials, operative technique, postoperative care, and complication management for cranioplasty.

Collagen-grafted porous HDPE/PEAA scaffolds for bone reconstruction

After tumor resection, bone reconstruction such as skull base reconstruction using interconnected porous structure is absolutely necessary. In this study, porous scaffolds for bone reconstruction were prepared using heat-pressing and salt-leaching methods. High-density polyethylene (HDPE) and poly(ethylene-co-acrylic acid) (PEAA) were chosen as the polymer composites for producing a porous scaffold of high mechanical strength and having high reactivity with biomaterials such as collagen, respectively. The porous structure was observed through surface images, and its intrusion volume and porosity were measured. Owing to the carboxylic acids on PEAA, collagen was successfully grafted onto the porous HDPE/PEAA scaffold, which was confirmed by FT-IR spectroscopy and electron spectroscopy for chemical analysis. Osteoblasts were cultured on the collagen-grafted porous scaffold, and their adhesion, proliferation, and differentiation were investigated. The high viability and growth of the osteoblasts suggest that the collagen-grafted porous HDPE/PEAA is a promising scaffold material for bone generation.

Evolution of cranioplasty techniques in neurosurgery: historical review, pediatric considerations, and current trends

Cranial bone repair is one of the oldest neurosurgical practices. Reconstructing the natural contours of the skull has challenged the ingenuity of surgeons from antiquity to the present day. Given the continuous improvement of neurosurgical and emergency care over the past century, more patients survive such head injuries, thus necessitating more than ever before a simple, safe, and durable means of correcting skull defects. In response, numerous techniques and materials have been devised as the art of cranioplasty has progressed. Although the goals of cranioplasty remain the same, the evolution of techniques and diversity of materials used serves as testimony to the complexity of this task. This paper highlights the evolution of these materials and techniques, with a particular focus on the implications for managing pediatric calvarial repair and emerging trends within the field.

Use of porous space maintainers in staged mandibular reconstruction

The success of mandibular reconstructions depends not only on restoring the form and function of lost bone but also on the preservation of the overlying soft tissue layer. In this case study, 5 porous polymethylmethacrylate space maintainers fabricated via patient-specific molds were implanted initially to maintain the vitality of the overlying oral mucosa during staged mandibular reconstructions. Three of the 5 patients healed well; the other 2 patients developed dehiscences, likely due to a thin layer of soft tissue overlying the implant. The results presented provide evidence that a larger investigation of space maintainers fabricated using this method is warranted.

Dural adhesion to porous cranioplastic implant: A potential safety concern

Background:

Patient-specific implants are used for cranioplastic skull reconstruction when large bone flaps must be replaced or where there are complex or critical contours, especially near the face. These implants have a low complication rate, with poor fit and postoperative infection being the most common complications. We report here a potentially serious hazard that may arise from the use of porous implants.

Case Description:

A 45-year-old woman sustained severe head trauma in a motor vehicle accident that required urgent surgical intervention. Because of progressive resorption of her native bone flap, she underwent replacement of her native flap with a hard tissue replacement/patient-matched implant cranioplasty. Eight years later, she sustained a traumatic laceration over her vertex that necessitated removal of her cranioplastic implant because of persistent local infection. Intraoperatively, the dural flap was ingrowing and firmly adherent to the inside surface of the porous cranioplasty. After several failed attempts to remove the whole implant piecemeal, we attempted to dissect the dural flap from the brain surface to remove it together with the cranioplastic implant but exposure of the extensive cortical adhesions between the brain surface and the dural flap was compromised by the hard overlying cranioplastic implant. Despite our meticulous attempts to cut off these cortical adhesions, a perisylvian blood vessel was avulsed, resulting in intraparenchymal hemorrhage.

Conclusion:

In this case, dural adhesion and ingrowth to the underside of the cranioplasty implant led to disastrous bleeding when the implant needed to be removed years after initial implantation.

Use of a Three-Dimensional Model to Optimize a MEDPOR Implant for Delayed Reconstruction of a Suprastructure Maxillectomy Defect

The use of a three-dimensional (3-D) model has been well described for craniomaxillofacial reconstruction, especially with the preoperative planning of free fibula flaps. This article reports the application of an innovative 3-D model approach for the calculation of the exact contours, angles, length, and general morphology of a prefabricated MEDPOR 2/3 orbital implant for reconstruction of a suprastructure maxillectomy defect. The 3-D model allowed intraoperative modification of the MEDPOR implant which decreased the risk of iatrogenic harm, contamination while also improving aesthetic results and function. With the aid of preoperative 3-D models, porous polypropylene facial implants can be contoured efficiently intraoperatively to precisely reconstruct complex craniomaxillofacial defects.

The use of abdominal free fat for volumetric augmentation and primary dural closure in supratentorial skull base surgery: managing the stigma of a temporal defect

The most prominent stigma of supratentorial skull base surgery is the defect caused by wasting of the temporalis muscle by denervation, devascularization, or rotation of the muscle. Any of the above may lead to a unilateral temporal deformity informally referred to patients as "the divot in my head." Abdominal free fat grafting has been used by surgeons for years to close posterior fossa defects with excellent results. We present our experience using abdominal free fat grafts to improve cosmetic results and to prevent cerebrospinal fluid leaks in supratentorial skull base surgery. The basic technique and its benefits are described.

Use of "custom made" porous hydroxyapatite implants for cranioplasty: postoperative analysis of complications in 1549 patients

Background:

Cranioplasty is a surgical intervention aimed at reestablishing the integrity of skull defects, and should be considered the conclusion of a surgical act that began with bone flap removal. Autologous bone is still considered the treatment of choice for cranioplasty. An alternative choice is bioceramic porous hydroxyapatite (HA) as it is one of the materials that meets and comes closest to the biomimetic characteristics of bone.

Methods:

The authors analyzed the clinical charts, compiled by the neurosurgeon, of all patients treated with custom-made porous HA devices (Custom Bone Service Fin-Ceramica, Faenza) from which epidemiological and pathological data as well as material-related complications were extrapolated.

Results:

From November 1997 to December 2010, 1549 patients underwent cranioplasty with the implantation of 1608 custom-made porous HA devices. HA was used in 53.8% of patients for decompressive craniectomy after trauma or intracranial hemorrhage, while the remaining cases were for treated for comminuted fracture, cutaneous or osseous resection, cranial malformation, autologous bone reabsorption or infection or rejection of previously implanted material. The incidence of adverse events in patients treated for cranioplasty, as first line treatment was 4.78% (56 events/1171 patients), and 5.02%, (19 events/378 patients) at second line.

Conclusion:

This study demonstrates that HA is a safe and effective material, is well tolerated in both adult and pediatric patients, and meets the requirements necessary to repair craniolacunia.

Calvarial reconstruction using high-density porous polyethylene cranial hemispheres

AIMS

Cranial vault reconstruction can be performed with a variety of autologous or alloplastic materials. We describe our experience using high-density porous polyethylene (HDPE) cranial hemisphere for cosmetic and functional restoration of skull defects. The porous nature of the implant allows soft tissue ingrowth, which decreases the incidence of infection. Hence, it can be used in proximity to paranasal sinuses and where previous alloplastic cranioplasties have failed due to implant infection.

MATERIALS AND METHODS

We used the HDPE implant in seven patients over a three-year period for reconstruction of moderate to large cranial defects. Two patients had composite defects, which required additional soft tissue in the form of free flap and tissue expansion.

RESULTS

In our series, decompressive craniectomy following trauma was the commonest aetiology and all defects were located in the fronto-parieto-temporal region. The defect size was 10 cm on average in the largest diameter. All patients had good post-operative cranial contour and we encountered no infections, implant exposure or implant migration.

CONCLUSIONS

Our results indicate that the biocompatibility and flexibility of the HDPE cranial hemisphere implant make it an excellent alternative to existing methods of calvarial reconstruction.

Preparation and comparative study of a new porous polyethylene ocular implant using powder printing technology

In this study, polyethylene (PE) was fabricated with porosity greater than 60% and 140—830 µm pore sizes which is suitable for fibrovascularization. The process involved three-dimensional printing of PE particles with water soluble adhesive powders followed by two-stepped heat treatment at 145°C with binder leaching between steps. Spherical ocular implants were fabricated by this process that had pore size, shaping and suturing ability comparable to commercially available porous PE (Medpor®), but had lower density, higher porosity, and antibiotic uptake, as well as, more uniform pore interconnectivity and lower needle exertion force for suturing.

Antibiotic-releasing porous polymethylmethacrylate constructs for osseous space maintenance and infection control

The use of a strategy involving space maintenance as the initial step of a two-stage regenerative medicine approach toward reconstructing significant bony or composite tissue defects in the craniofacial area, preserves the void volume of bony defects and could promote soft tissue healing prior to the subsequent definitive repair. One of the complications with a biomaterial-based space maintenance approach is local infection, which requires early, effective eradication, ideally through local antibiotic delivery. The purpose of this study is to develop a dual function implant material for maintaining osseous space and releasing an antibiotic to eliminate local infection in bony defects. Colistin, a polymyxin antibiotic, was chosen specifically to address infections with Acinetobacter species, the most common pathogen associated with combat-related traumatic craniofacial injuries. Porous polymethylmethacrylate (PMMA) constructs incorporating poly(lactic-co-glycolic acid) (PLGA) microspheres were fabricated by mixing a clinically used bone cement formulation of PMMA powder and methylmethacrylate liquid with a carboxymethylcellulose (CMC) hydrogel (40 or 50 wt%) to impart porosity and PLGA microspheres (10 or 15 wt%) loaded with colistin to control drug release. The PMMA/CMC/PLGA construct featured mild setting temperature, controllable surface/bulk porosity by incorporation of the CMC hydrogel, reasonably strong compressive properties, and continuous drug release over a period of 5 weeks with total drug release of 68.1-88.3%, depending on the weight percentage of CMC and PLGA incorporation. The concentration of released colistin was well above its reported minimum inhibitory concentration against susceptible species for 5 weeks. This study provides information on the composition parameters that enable viable porosity characteristics/drug release kinetics of the PMMA/CMC/PLGA construct for the initial space maintenance as part of a two-stage regenerative medicine approach.

Craniofacial reconstruction with bone and biomaterials: review over the last 11 years

This review aims to compare bone grafts and different biomaterials for reconstruction of craniofacial bones in congenital defects, after trauma, and after tumour surgery. A Pubmed search was performed and publications over the last 11 years describing reconstructions of craniofacial bones in non-load-bearing areas were reviewed. Only human studies using bone grafts and biomaterials were included. Studies on skull base reconstruction, distraction osteogenesis, free and pedicled bone flaps and bone-anchored epithesis were excluded. Out of 83 studies, three were prospective, 65 retrospective and 15 studies were case reports. There were seven comparative studies found and some efforts on statistical analysis were made. Except for a few studies, the statistical significant differences in outcomes were found to be related to size and location of bone defects rather than reconstruction method and biomaterial used. An increasing number of alloplastic materials have been available as alternatives to the gold standard autologous bone transplantation for craniofacial bone repair. Comparative studies with statistical analyses on differences in success rates between different biomaterials or bone grafts for specific indications are needed.

Congenital cavernous hemangioma of the calvaria. Case report

The authors present the case of a 6-month-old infant with a cavernous hemangioma of the parietal bone and discuss the radiological, operative, and pathological features and differential diagnosis of these extremely rare lesions in infants. Only 1 case of an infant with a calvarial cavernous hemangioma without intracranial invasion has previously been reported, and that case involved a 4 month old. Although a cavernous hemangioma of the calvaria is extremely rare in the newborn, this condition should be included in the differential diagnosis of calvarial lesions. During surgical treatment of calvarial cavernous hemangiomas, utmost attention should be paid to avoid blood loss, which could be fatal in infants.

Clinical evaluation of the polypropylene-polyester knit used as a cranioplasty material

The paper presents clinical evaluation of the polypropylene-polyester knit used as a cranioplasty material.

MATERIAL

Between year 1980 and 2002 275 cranioplastic procedures using the polypropylene-polyester plates Codubix were carried out in the Department of Neurosurgery of the Medical University of Łódź. There were 146 patients who primarily sustained head injuries and 129 non-traumatic patients with craniectomies carried out for various other reasons. In the majority of cases, i.e. in 158 patients, cranioplasty was performed later than 6 months after the primary surgery. The largest implant measured 430 cm2.

RESULTS

Excellent and good outcome was achieved in 92% of the patients whereas the rate of local infection was 8%.

CONCLUSIONS

Codubix knitted polypropylene-polyester implant proved to be useful and a safe cranioplastic material.