Autologous Cranial Bone Research Articles

Neurological functional outcome of early versus delayed cranioplasty following decompressive craniectomy at a tertiary care centre

Cranioplasty performed after a decompressive craniectomy (DC) for traumatic brain injury (TBI), stroke, or aneurysmal bleed has a role of restoring cerebral protection and craniofacial cosmesis as well as improving neuromotor function. There has been no consensus with regards to the ideal timing of cranioplasty (CP) after DC. A retrospective cohort study was carried out at a tertiary care hospital on patients who had undergone early (less than or equal to 12 weeks) and late (greater than 12 weeks) cranioplasty using autologous cranial bone after DC. Functional independence measure (FIM) tools were used to compare neuromotor and cognitive function outcome between the two groups. Appropriate statistical tools were used to compare neuromotor and cognitive function improvement as well as complication rates between early and late cranioplasty. A total of 31 adult patients of cranioplasty (21 male and 10 female) were evaluated. Sixteen had undergone early and 15 late cranioplasty. Comparison for neuromotor and cognitive function using FIM tools revealed statistically significant neuromotor and cognitive advantages in the early cranioplasty group. Overall complication rates between the two groups varied but were statistically insignificant. Performing an early cranioplasty provides advantages of improvement of neuromotor and cognitive function through early restoration of cerebrospinal fluid and intracerebral haemo-dynamics. It further avoids the potential problems of developing the ‘Syndrome of the Trephined’ (otherwise known as sinking skin flap syndrome) and resorption of the autologous bone.

Complications and Failures of Autologous Heterotopic Cranial Bone versus Alloplastic Cranioplasties.

Fresh autologous cranial bone graft has traditionally been regarded as the ideal cranioplasty material; however, long-term comparisons of outcomes with modern alloplastic materials are absent in the literature. The authors evaluated complications and failures among cranioplasties performed with fresh, heterotopic, cranial bone graft versus 3 common alloplastic materials. Random-effects meta-analyses of logit-transformed proportions were performed on studies published between 1971 and 2021 to evaluate complications and failures of cranioplasties performed with fresh, autologous, heterotopic cranial bone; polyetheretherketone (PEEK); polymethylmethacrylate (PMMA); or titanium with a mean follow-up of 12 months or more. Generalized mixed model meta-regressions were performed to account for heterogeneity and to evaluate the contributions of moderators to outcomes variables. A total of 1490 patients (mean age, 33.9 ± 10.8 years) were included. Pooled, all-cause complications were 6.2% for fresh, heterotopic, autologous cranial bone (95% CI, 2.1% to 17.0%; I2 = 55.0; P = 0.02), 18.5% for PEEK (95% CI, 14.0% to 24.0%; I2 = 0.0%; P = 0.58), 26.1% for titanium (95% CI, 18.7% to 35.1%; I2 = 60.6%; P < 0.01), and 28.4% for PMMA (95% CI, 12.9% to 51.5%; I2 = 88.5%; P < 0.01). Pooled all-cause failures were 2.2% for fresh autologous cranial bone (95% CI, 0.4% to 10.6%; I2 = 0.0%; P = 0.45), 6.3% for PEEK (95% CI, 3.2% to 12.3%; I2 = 15.5%; P = 0.31), 11.4% for titanium (95% CI, 6.7% to 18.8%; I2 = 60.8%; P < 0.01), and 12.7% for PMMA (95% CI, 6.9% to 22.0%; I2 = 64.8%; P < 0.01). Meta-regression models indicated that each alloplastic subtype significantly and independently predicted higher complications, whereas titanium and PMMA were significant predictors for all-cause failures compared with autologous bone. All 3 subtypes were predictive of higher cranioplasty failures secondary to infection compared with autologous bone. Cranioplasties performed with fresh, autologous, heterotopic cranial bone grafts resulted in lower complication and failure rates compared with alloplastic materials.

Management of Total Frontal Bone Loss After Surgery for Craniosynostosis: The Modified Visor Bone Flap With Brain Cage.

Complications after craniosynostosis surgery occur in 11% to 36% of cases and may be precipitated by poor soft tissue coverage and concomitant exposure of non-sterile regions; sequelae may result in infection, osteomyelitis, and bone loss requiring complex reconstruction. In the pediatric population, autologous cranioplasty remains the gold standard due to growth potential and a more favorable complication profile than synthetic cranioplasty. Virtual surgery planning (VSP) and computer-assisted design (CAD)/computer-assisted manufacturing (CAM) technology can be utilized to create innovative, patient-specific autologous solutions, similar to the approach with synthetic cranioplasty. A novel surgical approach using VSP was used for an 18-month-old female with near total bifrontal bone loss. Surface area measurements were used to determine the amount of bone available to replace the infected frontal bone. VSP was utilized to determine the most efficient construct configuration possible to achieve maximal coverage via calculation of cranial bone surface area measurements. Surgical reconstruction of the defect was planned as a Modified Visor Bone Flap with Posterior Brain Cage. A construct was fashioned from available cranial bone struts to obtain widespread coverage. 3D Recon images from before and after surgery demonstrate almost complete re-ossification of the cranial vault with significant resulting clinical improvement. Reconstruction of total frontal bone loss is possible by utilizing this technique. VSP can improve the safety and efficiency of complex autologous cranial bone reconstructions. We propose a treatment algorithm to address the problem of near total frontal bone loss in young children for whom alloplastic implants are not suitable.

Massive posterior cranial vault erosion and its reconstruction: A peculiar presentation of “mega cisterna magna”

Dandy-Walker (DW) complex is a rare central nervous system malformation, commonly associated with complex non-neurological conditions, defined by four variants with characteristic anatomic features, still inadequately known for its etiological aspects. “Mega Cisterna Magna” (MCM) is a type of DW complex which is represented by an enlarged posterior cranial fossa. Though reduction cranioplasty has been reported in enlarged posterior cranial fossa malformations, however we report a peculiar case of MCM with massive posterior cranial bone erosion, presenting completely asymptomatic at an age of 8 years, without any associated co-morbidities till date, nor with any evident occipital mass at birth. Survival of the child till this age is an exception in itself, but this can probably be explained by the presence of the giant defect of the posterior cranial bone, which must have acted like a vent and prevented the elevation of the ICP. Hence no symptoms were observed till date. Ventriculo-peritoneal (VP) shunting was done to drain the accumulated fluid, followed by massive cranioplasty, which was challenging and was performed with autologous cranial and fibular bone grafts, along with alloplastic titanium mesh, and thus achieving marked aesthetic improvement with satisfactory bone healing at a 3-year follow-up.

Cryopreservation of Autologous Cranial Bone Flaps for Cranioplasty: A Large Sample Retrospective Study.

To clarify the clinical outcomes of cranioplasty with cryopreserved bone flaps and identify risk factors related to bone flap infection and resorption after cranioplasty with cryopreserved bone flaps. A total of 946 patients (989 bone flaps) underwent decompressive craniectomy and delayed cranioplasty via the use of cryopreserved autogenous cranial bone flaps. Cranial bone flaps were removed during the initial craniectomy and reserved in liquid nitrogen (-196°C) with dimethyl sulfoxide as a cryoprotectant. Cranioplasty subsequently was performed once the brain injury had healed. Data regarding complications and clinical outcomes were recorded and the potential risk factors were analyzed. Data from 960 flaps were available for analysis. The overall complication rate was 15.83% (152 of 960). Bone resorption occurred in 42 flaps in 37 patients (4.38%). The bone flaps resorption rate was greater in patients ≤18 years than in patients >18 years (9.38% vs. 3.61%, P < 0.05). Cryopreservation for more than 365 days tended to result in a greater bone resorption rate (6.88% vs. 2.92%, P < 0.01). Skull bone grafts infection occurred in 39 flaps in 34 patients (4.06%). The bone graft infection rate was greater in emergency craniectomy cases (8.81% vs. 2.59%, P < 0.01) and in patients with diabetes (10.53% vs. 3.07%, P < 0.01). Cryopreservation of autologous cranial bone flaps is safe and effective for cranioplasty. Cranioplasty with cryopreserved autologous cranial bone flaps should be performed no more than 1 year after craniectomy. Emergency craniectomy and patients with diabetes require special attention.

Biomimetic approaches to complex craniofacial defects.

The primary goals of craniofacial reconstruction include the restoration of the form, function, and facial esthetics, and in the case of pediatric patients, respect for craniofacial growth. The surgeon, however, faces several challenges when attempting a reconstructive cranioplasty. For that reason, craniofacial defect repair often requires sophisticated treatment strategies and multidisciplinary input. In the ideal situation, autologous tissue similar in structure and function to that which is missing can be utilized for repair. In the context of the craniofacial skeleton, autologous cranial bone, or secondarily rib, iliac crest, or scapular bone, is most favorable. Often, this option is limited by the finite supply of available bone. Therefore, alternative strategies to repair craniofacial defects are necessary. In the field of regenerative medicine, tissue engineering has emerged as a promising concept, and several methods of bone engineering are currently under investigation. A growth factor-based approach utilizing bone morphogenetic proteins (BMPs) has demonstrated stimulatory effects on cranial bone and defect repair. When combined with cell-based and matrix-based models, regenerative goals can be optimized. This manuscript intends to review recent investigations of tissue engineering models used for the repair of craniofacial defects with a focus on the role of BMPs, scaffold materials, and novel cell lines. When sufficient autologous bone is not available, safe and effective strategies to engineer bone would allow the surgeon to meet the reconstructive goals of the craniofacial skeleton.

Does Mastoid Obliteration following Mastoidectomy Offer an Improvement in Quality of Life?

Objectives: 1) Recognize the impact mastoidectomy with obliteration has on quality of life (QOL). 2) Describe the QOL change with primary or secondary mastoid obliteration with autologous bone graft. 3) Review of the literature on mastoid obliteration. Methods: This retrospective observational study was conducted to determine if mastoid obliteration with autologous cranial bone graft following mastoidectomy improves QOL. Patients with cholesteatoma who had mastoidectomy with primary or secondary mastoid obliteration by a tertiary otologist were surveyed using the validated Glasgow Benefit Inventory (GBI), our primary outcome measure. Our secondary outcomes were recurrence rates. Results: Fifty-five patients were interviewed: 44 were primary obliterations, and 11 were secondary obliterations of an existing mastoid cavity. Overall GBI scores were improved, with average scores of 25. Average general subscale scores were 26, physical health scores were 22, and social health scores were 24. The primary obliteration group had average scores of 22, general subscale scores of 23, physical health scores of 21, and social health scores of 19. Those with secondary obliteration scored higher, with average scores of 37, general subscale scores of 40, physical health scores of 21, and social health scores of 42. Recurrence rates were comparable with the current literature. Conclusions: This study shows that mastoidectomy with obliteration using autologous cranial bone graft offers a significant QOL benefit. The GBI scores compare favorably with other otology procedures. Secondary obliterations after revision mastoidectomy scored much higher than primary obliterations. This is currently the only QOL study comparing these two patient groups.

Computer-assisted midface reconstruction in Treacher Collins syndrome part 1: Skeletal reconstruction

IntroductionTreacher Collins syndrome (TCS) is a severe and complex craniofacial malformation affecting the facial skeleton and soft tissues. The palate as well as the external and middle ear are also affected, but his prognosis is mainly related to neonatal airway management. Methods of zygomatico-orbital reconstruction are numerous and currently use primarily autologous bone, lyophilized cartilage, alloplastic implants, or even free flaps. This work developed a reliable “customized” method of zygomatico-orbital bony reconstruction using a generic reference model tailored to each patient. MethodsFrom a standard computed tomography (CT) acquisition, we studied qualitatively and quantitatively the skeleton of four individuals with TCS whose age was between 6 and 20 years. In parallel, we studied 40 controls at the same age to obtain a morphometric database of reference. Surgical simulation was carried out using validated software used in craniofacial surgery. ResultsThe zygomatic hypoplasia was very important quantitatively and morphologically in all TCS individuals. Orbital involvement was mainly morphological, with volumes comparable to the controls of the same age. The control database was used to create three-dimensional computer models to be used in the manufacture of cutting guides for autologous cranial bone grafts or alloplastic implants perfectly adapted to each patient's morphology. Presurgical simulation was also used to fabricate custom positioning guides permitting a simple and reliable surgical procedure. ConclusionsThe use of a virtual database allowed us to design a reliable and reproducible skeletal reconstruction method for this rare and complex syndrome. The use of presurgical simulation tools seem essential in this type of craniofacial malformation to increase the reliability of these uncommon and complex surgical procedures, and to ensure stable results over time.

Single-Donor Allogeneic Platelet Fibrin Glue and Osteoconductive Scaffold in Orbital Floor Fracture Reconstruction

Commonly used materials for orbital floor fracture reconstruction include autologous cranial bone graft and titanium mesh. We have evaluated here a biomaterial combining biphasic calcium phosphate (hydroxyapatite [HA]/β-tricalcium phosphate [TCP]) osteoconductive scaffold with single-donor allogeneic platelet fibrin glue. The study was conducted on 10 consecutive patients with a follow-up of up to 4 years. Platelet fibrin glue was prepared by mixing equal volumes of single-donor platelet-rich plasma and cryoprecipitate with HA/β-TCP followed by activation with human thrombin prepared by plasma activation. Postoperative evaluations included serial photographs, repeated physical examination, and 3-dimensional computed tomography scan performed 2 years after surgery. The fibrin-rich platelet biomaterial was easy to mold and to apply on the surgical site allowing the surgeon to sculpt accurately the bone defect, providing mechanical stability while avoiding spillage of the scaffold. No infection of the orbit or extrusion of HA/β-TCP was observed. Ocular motility was normal, and no diplopia or enophthalmos of the injured orbit was noted. Coronal computed tomography scans of the reconstructed orbits revealed good restoration of the orbital floor defect in all 10 patients. The use of single-donor platelet fibrin glue combined with an osteoconductive scaffold offers a valuable alternative to autologous cranial bone graft or titanium mesh in the reconstruction of orbital floor bone defect.

Mastoidectomy and mastoid obliteration with autologous bone graft: A quality of life study

BackgroundA mastoid cavity resulting from a canal wall down mastoidectomy can result in major morbidity for patients due to chronic otorrhea and infection, difficulty with hearing aids and vertigo with temperature changes. Mastoid obliteration with reconstruction of the bony external ear canal recreates the normal anatomy to avoid such morbidity. Few have the studied the quality of life benefit that this procedure confers.MethodsThis retrospective observational study was conducted to determine if mastoid obliteration with autologous cranial bone graft following mastoidectomy improves quality of life (QOL). Patients with cholesteatoma who had mastoidectomy with primary or secondary mastoid obliteration by a tertiary otologist were surveyed using the validated Glasgow Benefit Inventory (GBI), our primary outcome measure.ResultsFifty-eight patients were interviewed. Forty-six were primary obliteration after canal wall down mastoidectomy of a primary cholesteatoma. Twelve were secondary obliteration of an existing canal wall down mastoid cavity. Overall GBI scores were improved, with average scores of 22. Average general subscale scores were 23, physical health scores were 25, and social health scores were 22. The primary obliteration group had average scores of 19, general subscale scores of 20, physical health scores of 21, and social health scores of 22. Those with secondary obliteration scored higher, with average scores of 31, general subscale scores of 34, physical health scores of 39, and social health scores of 25.ConclusionThis study shows that mastoidectomy with obliteration using autologous cranial bone graft offers a significant QOL benefit. The GBI scores compare favourably with other otorhinolaryngology procedures. Secondary obliterations after revision mastoidectomy scored much higher than primary obliterations. This is currently the only QOL study comparing these two patient groups.

Survival and regeneration of deep-freeze preserved autologous cranial bones after cranioplasty

Background. After decompressive craniectomy, a deep-freeze-preserved autologous cranial bone graft can be used for cranioplasty to avoid immunoreaction against an artificial patch material. Autologous cranial bone grafts not only have better physical properties, such as heat conduction, compared to artificial patch materials, but they also have the advantages of a lower medical cost and satisfactory physical flexibility. The discussion over 99Tcm-MDP SPECT static cranial bone tomography in the diagnosis of survival and regeneration in deep-freeze preservation autologous cranial bones after cranioplasty is valuable. Objective. To investigate whether deep-freeze-preserved autologous cranial bone grafts could survive and regenerate after autologous reimplantation. Methods. The method of cranial bone preservation involved removing the cranial graft and sealing it in a double-layer sterile plastic bag under sterile surgical conditions. On the day of the cranioplasty operation, the cranial bone graft was disinfected by immersing it in 3% povidone–iodine for 30 minutes. At short-term (2 weeks), medium-term (3 months), and long-term (12 months) postoperative follow-up visits, 99Tcm-MDP SPECT static cranial bone tomography was used to examine the reimplanted cranial bone. Results. There were no postoperative infections or seromas in all 16 cases. Two weeks following cranial bone graft reimplantation, the SPECT tomography showed some radioactivity uptake in the reimplanted cranial bone graft, which was lower than that in the cranial bone on the healthy side. At 3 months and 12 months after the operation, the radioactivity uptake in the reimplanted cranial bone graft was the same as that in the cranial bone on the healthy side. X-ray films showed blurred sutures in the reimplanted cranial bone graft at 12 months after surgery. Conclusion. Reimplanted deep-freeze-preserved autologous cranial bone can survive in the short term and regenerate in the medium and long terms.

Evaluation of super-hypothermally preserved autologous cranial bones for cranioplasty with SPECT

Objective To explore the clinic value of 99Tcm - MDP SPECT in the diagnosis of survival and regeneration of super - hypothermally preserved autologous cranial bones for cranioplasty. Method All 16 cases of skull defect after decompressive craniectomy had been replanted with super - hypothermally ( - 80℃ ) preserved autologous cranial bones. The time of cranioplasty ( namely autologous cranial bone preservation time) was 63 -289 days( 111.7 days in average). 99Tcm - methylene diphosphonate( MDP) SPECT was used to detect replanted autologous cranial bone at the end of 2nd weeks, 3rd month and 12th month after cranioplasty. Results 99Tcm - MDP SPECT examination showed that the radionuclide uptake in grafts at the end of the 2nd weeks was sparse after cranioplasty, which was less than the contralateral normal side. The radionuclide uptake in grafts at the end of the 3rd month and 12th month after cranioplasty were the same as that of the contralateral normal side. Conclusions 99Tcm - MDP SPECT could detect survival of transplanted super - hypothermally preserved autologous cranial bones for cranioplasty and regeneration in medium and long term after cranioplasty. Key words: Cryopreservation; Autologous cranial bone; Cranioplasty; Tomography, emission - computed, single - photon

Autologous Cranial Particulate Bone Grafting Reduces the Frequency of Osseous Defects After Cranial Expansion

Primary autologous particulate bone grafting has been demonstrated to heal osseous defects after fronto-orbital advancement. We sought to determine if this technique was equally effective for larger defects resulting from major cranial expansion procedures. We studied children who underwent cranial expansion (other than fronto-orbital advancement) between 1989 and 2008. Defects either were left to heal spontaneously (group 1) or had autologous cranial particulate bone graft placed over dura at the time of cranial expansion (group 2). Particulate bone graft was harvested from the endocortical or ectocortical surface using a hand-driven brace and bit. Outcome variables were ossification and need for revision cranioplasty. The study included 53 children. Mean (SD) age at procedure was 12.2 (8.1) months (range, 1.0-36.0 months) for group 1 (n = 15) and 20.2 (15.1) months (range, 3.3-78.6 months) for group 2 (n = 38) (P = 0.06). There were palpable bony defects in 33.0% (n = 5) of group 1 patients versus 7.9% (n = 3) of group 2 patients (P = 0.03). Corrective cranioplasty was needed in 26.7% of group 1 patients and only 5.3% of those in group 2 (P = 0.04). Primary cranial particulate bone grafting significantly reduced the frequency of osseous defects and secondary cranioplasty following cranial remodeling.

Pediatric Cranioplasty Using Particulate Calvarial Bone Graft

Closure of calvarial defects in children is problematic because the supply of autologous bone is limited and alloplastic materials are not advocated. The authors previously showed that cranial particulate bone graft applied over the coronal gap during primary fronto-orbital advancement reduced the incidence of residual osseous defects. The purpose of this study was to determine the effectiveness of particulate bone graft for established calvarial defects. The authors analyzed consecutive children who had undergone cranioplasty with inlay particulate bone grafting between 1989 and 2007. Particulate bone was harvested from parietal calvaria or from the endocortex of the cranial elements using a hand-driven brace and bit. Patient records were reviewed for age at the time of cranioplasty, operative indication, size of defect, and length of follow-up. Outcome variables included persistent osseous defects, need for further cranioplasty, and complications. Thirty-eight children had inlay particulate bone grafting at an average age of 8.0 years (range, 3 to 20 years). The average defect size was 66.5 cm (range, 5 to 250 cm). Indications for inlay grafting were revision fronto-orbital advancement, bony gaps following primary cranial remodeling, congenital defects, trauma, and tumor. Mean follow-up was 6.1 years (range, 0.5 to 18 years). Three patients (7.9 percent) had small persistent osseous defects, and one (2.6 percent) required another cranioplasty. Inlay autologous cranial particulate bone graft effectively heals established cranial defects in children. Particulate bone graft can be harvested in infants and young children, does not require neurosurgical assistance, and has minimal morbidity.

Primary Grafting with Autologous Cranial Particulate Bone Prevents Osseous Defects following Fronto-Orbital Advancement

Approximately 20 percent of patients require cranioplasty for defects after fronto-orbital advancement. The authors hypothesized that corticocancellous cranial particulate bone placed over exposed dura at the time of fronto-orbital advancement would decrease the frequency of incomplete ossification. The authors retrospectively analyzed consecutive children who underwent fronto-orbital advancement for craniosynostosis between 1988 and 2006. In group I, cranial gaps resulting from frontal advancement were left open and allowed to heal spontaneously. In group II, corticocancellous particulate bone was used to fill the calvarial defects. Bone was harvested from the endocortex of the frontal segments or parietal calvaria using a hand-driven brace and bit. Outcome variables were persistent osseous defects and need for corrective cranioplasty. The study included 213 children. There were 50 patients in group I: mean age at fronto-orbital advancement was 7.0 months (range, 2 to 15 months); 12 patients (24 percent) had residual defects and 10 (20 percent) required cranioplasty. Group II contained 163 patients: mean age at fronto-orbital advancement was 14.1 months (range, 6 to 72 months); nine children (5.5 percent) had a cranial defect and five (3.1 percent) required cranioplasty. Infants in group II were less likely to have bony defects (p = 0.0005) or require cranioplasty (p = 0.0002) compared with children in group I, despite being older at the time of fronto-orbital advancement (p = 0.001). Corticocancellous cranial particulate bone grafting during fronto-orbital advancement reduces the prevalence of osseous defects and the need for secondary cranioplasty, independent of patient age.

Nasal bone haemangiomas: rare entities treatable by craniofacial approach

Three cases of haemangioma of the nasal bone are illustrative of a rare clinical entity. These were treated by current craniofacial surgical techniques. The advantages of this approach are obvious minimising of the facial deformity, obtaining autologous cranial bone graft and rigid fixation to enhance stability and minimise resorption.