Minimally invasive surgeries for spontaneous hypertensive intracerebral hemorrhage (MISICH): a multicenter randomized controlled trial.

BACKGROUND: Intracerebral hemorrhage (ICH) is a common stroke type with high morbidity and mortality. There are mainly three surgical methods for treating ICH. Unfortunately, thus far, no specific surgical method has been proven to be the most effective. We carried out this study to investigate whether minimally invasive surgeries with endoscopic surgery or stereotactic aspiration (frameless navigated aspiration) will improve functional outcomes in patients with supratentorial ICH compared with small-bone flap craniotomy. METHODS: In this parallel-group multicenter randomized controlled trial conducted at 16 centers, patients with supratentorial hypertensive ICH were randomized to receive endoscopic surgery, stereotactic aspiration, or craniotomy at a 1:1:1 ratio from July 2016 to June 2022. The follow-up duration was 6 months. Patients were randomized to receive endoscopic evacuation, stereotactic aspiration, or small-bone flap craniotomy. The primary outcome was favorable functional outcome, defined as the proportion of patients who achieved a modified Rankin scale (mRS) score of 0-2 at the 6-month follow-up. RESULTS: A total of 733 patients were randomly allocated to three groups: 243 to the endoscopy group, 247 to the aspiration group, and 243 to the craniotomy group. Finally, 721 patients (239 in the endoscopy group, 246 in the aspiration group, and 236 in the craniotomy group) received treatment and were included in the intention-to-treat analysis. Primary efficacy analysis revealed that 73 of 219 (33.3%) in the endoscopy group, 72 of 220 (32.7%) in the aspiration group, and 47 of 212 (22.2%) in the craniotomy group achieved favorable functional outcome at the 6-month follow-up (P = .017). We got similar results in subgroup analysis of deep hemorrhages, while in lobar hemorrhages the prognostic outcome was similar among three groups. Old age, deep hematoma location, large hematoma volume, low preoperative GCS score, craniotomy, and intracranial infection were associated with greater odds of unfavorable outcomes. The mean hospitalization expenses were ¥92,420 in the endoscopy group, ¥77,351 in the aspiration group, and ¥100,947 in the craniotomy group (P = .000). CONCLUSIONS: Compared with small bone flap craniotomy, endoscopic surgery and stereotactic aspiration improved the long-term outcome of hypertensive ICH, especially deep hemorrhages. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02811614.

"Revolutionizing retrosigmoid surgical precision: AI in free bone flap reconstruction".

Free bone flap reconstruction is essential to the retrosigmoid method of microvascular decompression (MVD) and can completely transform surgical methods worldwide. According to studies like Liao et al. (2023), 92.3% of patients report feeling better after receiving treatment. The study by Shize Li et al. emphasizes the affordability and accessibility of free bone flap reconstruction, demonstrating shorter recovery times, lower expenses, and similar rates of complications to those of conventional fixation techniques. With benefits like fewer headaches and a quicker recovery in the free bone flap group, their retrospective analysis of 189 patients showed no significant differences in hospital stay or complication rates between the fixed and unfixed bone flap groups.Despite these results, larger sample sizes and longer-term studies are needed to confirm these findings and address issues such as leakage of cerebrospinal fluid. Furthermore, adding Artificial Intelligence (AI) to this method may improve accuracy and results. AI has the potential to enhance MVD procedures and patient outcomes through its capacity to create 3D models, direct bone flap placement, and track postoperative progress. Standardizing AI's application in clinical practice still presents difficulties, though. In the end, even though Shize Li et al.'s research significantly advances the body of knowledge already in existence, more creativity and investigation are required to maximize free bone flap reconstruction in MVD.

Scalp incision technique for decompressive hemicraniectomy: comparative systematic review and meta-analysis of the reverse question mark versus alternative retroauricular and Kempe incision techniques.

Decompressive hemicraniectomy (DHC) is a critical procedure used to alleviate elevated intracranial pressure (ICP) in emergent situations. It is typically performed to create space for the swelling brain and to prevent dangerous and potentially fatal increases in ICP. DHC is indicated for pathologies ranging from MCA stroke to traumatic subarachnoid hemorrhage-essentially any cause of refractory brain swelling and elevated ICPs. Scalp incisions for opening and closing the soft tissues during DHC are crucial to achieve optimal outcomes by promoting proper wound healing and minimizing surgical site infections (SSIs). Though the reverse question mark (RQM) scalp incision has gained significant traction within neurosurgical practice, alternatives-including the retroauricular (RA) and Kempe incisions-have been proposed. As choice of technique can impact postoperative outcomes and complications, we sought to compare outcomes associated with different scalp incision techniques used during DHC. We queried three databases according to PRISMA guidelines in order to identify studies comparing outcomes between the RQM versus "alternative" scalp incision techniques for DHC. Our primary outcome of interest in the present study was postoperative wound infection rates according to scalp incision type. Secondary outcomes included estimated blood loss (EBL) and operative duration. We identified seven studies eligible for inclusion in the formal meta-analysis. The traditional RQM technique shortened operative times by 36.56 min, on average. Additionally, mean EBL was significantly lower when the RQM scalp incision was used. Postoperatively, there was no significant association between DHC incision type and mean intensive care unit (ICU) length of stay (LOS), nor was there a significant difference in predisposition to developing wound complications or infections between the RQM and retroauricular/Kempe incision cohorts. Superficial temporal artery (STA) preservation and reoperation rates were collected but could not be analyzed due to insufficient number of studies reporting these outcomes. Our meta-analysis suggests that there is no significant difference between scalp incision techniques as they relate to surgical site infection and wound complications. At present, it appears that outcomes following DHC can be improved by ensuring that the bone flap is large enough to enable sufficient cerebral expansion and decompression of the temporal lobe, the latter of which is of particular importance. Although previous studies have suggested that there are several advantages to performing alternative scalp incision techniques during DHC, the present study (which is to our knowledge the first to meta-analyze the literature on outcomes in DHC by scalp incision type) does not support these findings. As such, further investigations in the form of prospective trials with high statistical power are merited.

Cryopreserved bone flaps from decompressive craniectomies: a microbiological analysis.

PURPOSE: Surgical site infection (SSI) is a serious complication after cranioplasty. Due to the relatively frequent occurrence of post-cranioplasty SSI, the utility of autologous bone flap swab cultures surrounding cryopreservation as a reliable predictor has been the subject of an ongoing debate. This bicentric study aims to contribute to this topic by conducting an in-depth analysis of bone flaps obtained via decompressive craniectomies. This study had three major aims: assessments of 1) bacterial contamination of bone flaps after decompressive craniotomy, 2) impact of cryoconservation on contamination rates and 3) potential effectiveness of anti-infective treatment to reduce the germ load prior to cranioplasty. METHODS: Cryopreserved bone flaps from two centers were used. Microbiological cultivations of swabs prior to and after cryopreservation were taken and assessed for aerobic and anaerobic growth over a 14-day incubation period. Additionally, in a subset of bone flaps, swab testing was repeated after thorough rinsing with an anti-infectant (octenidine-phenoxyethanol) followed by saline. RESULTS: All 63 bone flaps (patients median age at surgery: 59 years) were obtained via decompressive craniectomies. Swabs done prior to cryopreservation revealed a 54% infection rate with Propionibacterium acnes being the most common microorganism in 65% of those cases. After thorough disinfection of the preserved bone flaps, all but one case showed no bacterial growth in swab testing. Furthermore, no relevant risk factors for bacterial contamination could be identified. CONCLUSION: This retrospective study showed the common presence of bacterial growth in cryopreserved bone flaps before and after freezing. Rinsing with octenidine-phenoxyethanol and saline effectively prevented bacterial growth in a notable percentage of cases, suggesting a potential strategy to reduce contamination. However, persistent bacterial growth in some cases underscores the need for further research to optimize antiseptic measures during autologous cranioplasty.

Complication rates after autologous cranioplasty following decompressive craniectomy.

OBJECTIVE: The reimplantation of autologous bone grafts after decompressive craniectomy (DC) is still up for debate. The objective of this study was to analyze the surgical revision rate for autologous cranioplasties in our center, aiming to identify predictors for procedure-related-complications. METHODS: A retrospective single-center study was conducted for adult patients who underwent autologous cranioplasty after DC. The primary endpoint was the complication rate in terms of surgical revision and removal of the bone graft: infection, new onset seizures, dislocation, haemorrhage, osteolysis, wound dehiscence and cerebrospinal fluid (CSF) fistula. Demographic data, medical records, surgical reports and imaging studies were analysed and risk factors for complications were evaluated. RESULTS: 169 consecutive patients were included. The median interval between DC and cranioplasty was 84 days. Mean age was 51 ± 12.4 years. 26 patients (15.3%) had revision surgery for following reasons. n = 9 implant dislocations (5.3%), n = 7 osteolysis (3.6%), n = 6 infections (3.6%), n = 5 had re-bleedings (3%), n = 5 wound dehiscences (3%), and n = 2 CSF fistulas (1.2%). 18 patients developed new seizures (10.7%). Bi- and multivariate analysis revealed three independent risk factors, simultaneous ventriculo-peritoneal (VP) shunting increased the risk for material dislocation (p < 0.001); large bone grafts (> 193.5 cm2) increased the risk for osteolysis (p = 0.001) and bifrontal cranioplasties were associated with higher risk for infections (p = 0.04). CONCLUSION: The complication rates in our study were comparable to previously reported data for autologous or artificial cranioplasties. As osteolysis was correlated to larger bone grafts, a synthetic alternative should be considered in selected cases.

A study on the morphology of iliac crest based on the objectives of jaw bone defect reconstruction.

OBJECTIVES: to understand the morphological characteristics of iliac crest and provide advice and assistance for jaw bone reconstruction with iliac bone flap by evaluating the thickness and curvature of iliac crest. MATERIALS AND METHODS: 100 patients who had taken Spiral CT of the Abdominal region before surgeries between 2020 and 2022 were included in this study. 3D reconstruction images of the iliac bones were created. 5 vertical planes perpendicular to the iliac crest were made every 2 cm along the centerline of the iliac crest (VP2 ~ VP10). On these vertical planes, 4 perpendicular lines were made every 1 cm along the long axis of the iliac crest (D1 ~ D4). The thicknesses at these sites, horizontal angle (HA) of iliac crest and the distance between inflection point and the central point of anterior superior iliac spine (DIA) were measured. RESULTS: The thickness of iliac bone decreased significantly from D1 ~ D4 on VP6 ~ VP10 and from VP2 ~ VP10 on D3 and D4 level (P<0.05). HA of iliac crests was 149.13 ± 6.92°, and DIA was 7.36 ± 1.01 cm. Iliac bone thickness, HA and DIA had very weak or weak correlation with patient's age, height and weight. CONCLUSIONS: The average thicknesses of iliac crest were decreased approximately from front to back, from top to bottom. The thickness and curvature of the iliac crest were difficult to predict by age, height and weight. CLINICAL RELEVANCE: Virtual surgical planning is recommended before jaw bone reconstruction surgery with iliac bone flap, and iliac crest process towards alveolar process might be a better choice.

Conversion Total Hip Arthroplasty After Pedicled Peri-Hip Bone Flap Grafting: The Chinese Experience.

BACKGROUND: This study investigated the perioperative outcomes of patients undergoing conversion total hip arthroplasty (THA) after failed peri-hip bone flap grafting (PBFG) and compared them with those patients undergoing primary THA for osteonecrosis of the femoral head (ONFH). METHODS: From January 2010 to December 2021, 163 Chinese patients (163 hips) were treated by conversion THA after failed PBFG (containing 94 patients who had pedicled vascularized iliac bone flap grafting and 69 patients who had pedicled vascularized greater trochanter bone flap grafting), and 178 Chinese patients were treated by primary THA. The preoperative baseline data and perioperative indicators in both groups were compared. RESULTS: In the conversion group, patients had significantly greater blood loss, a longer length of stay, and greater changes in serum hemoglobin than those in the primary THA group (P < 0.05). The operative room time, transfusion volume, calculated blood loss, changes in serum hematocrit, and increased superficial infection (P > 0.05) in the conversion group were greater compared with the primary cohort; however, the difference was not statistically significant. The mean postoperative Harris Hip Scoring system (HHS) of the PBFG group at the 1-month follow-up was 81, and the control group had a score of 82. Importantly, subgroup analysis of the PBFG group indicated that there was no significant difference between patients who had prior pedicled vascularized iliac bone flap grafting and pedicled vascularized greater trochanter bone flap grafting (P > 0.05), except for the operative room time (P = 0.032). CONCLUSIONS: Hip-sparing surgery of ONFH did not make THA more difficult or lead to more perioperative complications, but increased blood loss and extended hospital stay from a prior PBFG are still notable problems in clinical practice. Thus, it is necessary for surgeons to focus attention on the improvement of the preoperative condition and prepare for any specific intraoperative challenges.

[Histopathological characteristics of peri-implant soft tissue in reconstructed jaws with vascularized bone flaps].

OBJECTIVE: To analyze the histopathological characteristics of peri-implant soft tissue in reconstructed jaws and the changes after keratinized mucosa augmentation (KMA) with free gingival graft (FGG). METHODS: Twenty patients were enrolled in this study. Five patients of them, who were periodontal and systemic healthy and referred for crown lengthening before restoration with healthy keratinized gingiva collected were enrolled as healthy controls. 15 patients of them were with fibula or iliac bone flaps jaw reconstruction (10 with fibula flap and 5 with iliac flap), who were referred to FGG and implant exposures before restoration. Soft tissue was collected before FGG in reconstructed jaws, and in 5 patients (3 with fibula flap and 2 with iliac flap) 8 weeks after FGG if a second surgery was conducted. Histological analysis with hematoxylin-eosin stain and immunological analysis to interlukin-1 (IL-1), interlukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were performed. RESULTS: Thickness from the bottom of stratum basale to the top of stratum granulosum and thickness of keratinized layer in reconstructed jaws were significantly lower compared with that of natural healthy keratinized gingiva [0.27 (0.20, 0.30) mm vs. 0.36 (0.35, 0.47) mm, P<0.05; 16.49 (14.90, 23.37) µm vs. 26.37 (24.12, 31.53) µm, P<0.05]. In the reconstructed area, thickness from the bottom of stratum basale to the top of stratum granulosum increased after KMA with FGG [0.19 (0.16, 0.25) mm vs. 0.38 (0.25, 0.39) mm, P=0.059] and the thickness of keratinized layer significantly increased after KMA with FGG [16.42 (14.16, 22.35) µm vs. 28.57 (27.16, 29.14) µm, P<0.05], which was similar to that in the control group. Furthermore, the number of positive cells of IL-1, IL-6 and TNF-α significantly increased after KMA [0.67 (0.17, 8.93) vs. 11.00 (9.16, 18.00); 13.00 (8.50, 14.14) vs. 21.89 (15.00, 28.12); 0.22 (0.04, 0.63) vs. 2.83 (1.68, 5.00), respectively, P<0.05] as well as the average optical density value [0.15 (0.14, 0.17) vs. 0.18 (0.17, 0.21); 0.28 (0.26, 0.33) vs. 0.36 (0.33, 0.37); 0.23 (0.22, 0.29) vs. 0.30 (0.28, 0.42), respectively, P<0.05], which was similar to that in the healthy keratinized gingiva. CONCLUSION: The lack of rete pegs and inflammatory factors were common in soft tissue with jaw reconstruction. FGG can improve the quality of the epithelium and may improve the stability of the mucosa around implants.

Iliac crest towards alveolar processes or mandibular inferior margin in mandibular reconstruction with a vascularized iliac bone flap: which is better?

OBJECTIVE: The study aims to compare differences among iliac bone flaps with different iliac crest orientations for the repair of mandibular defects with an aim to analyze their advantages, disadvantages, and effects. MATERIAL AND METHODS: Clinical data and computed tomography scans of all patients who underwent iliac bone flap repair of the mandible in Peking University School and Hospital of Stomatology from January 2016 to April 2021 were collected. Patients were divided into the iliac crest towards alveolar process (Group A) and the iliac crest towards mandibular inferior margin (Group B). Software was used to measure corresponding indicators. The results obtained for the groups were statistically analyzed. RESULTS: The study included 78 patients (25 and 53 in groups A and B, respectively). The symmetry of the LC-type defect was better in group A (p < 0.05). The all-bone width of the alveolar process side in group A was greater than 6 mm; in 15 cases of group B, the width was less than 6 mm (p < 0.05). The intermaxillary distance of two sites were higher in group B (p < 0.05). The bone cortical thickness was significantly thicker in group A (p < 0.05). CONCLUSION: One year after the mandibular body defect was reconstructed with a vascularized iliac bone flap, the iliac crest towards alveolar process group showed better bone symmetry, width, intermaxillary distance, and cortical thickness to meet the planting requirements. CLINICAL RELEVANCE: The use of an iliac crest towards alveolar process may be a better approach for mandible reconstruction.

Protocol for the multicentre prospective paediatric craniectomy and cranioplasty registry (pedCCR) under the auspices of the European Society for Paediatric Neurosurgery (ESPN).

PURPOSE: In the paediatric age group, the overall degree of evidence regarding decompressive craniectomy (DC) and cranioplasty is low, whereas in adults, randomised controlled trials and prospective multicentre registries are available. To improve the evidence-based treatment of children, a consensus was reached to establish a prospective registry under the auspices of the European Society for Pediatric Neurosurgery (ESPN). METHODS: This international multicentre prospective registry is aimed at collecting information on the indication, timing, technique and outcome of DC and cranioplasty in children. The registry will enrol patients ≤ 16 years of age at the time of surgery, irrespective of the underlying medical condition. The study design comprises four obligatory entry points as a core dataset, with an unlimited number of further follow-up entry points to allow documentation until adolescence or adulthood. Study centres should commit to complete data entry and long-term follow-up. RESULTS: Data collection will be performed via a web-based portal (homepage: www.pedccr.com ) in a central anonymised database after local ethics board approval. An ESPN steering committee will monitor the project's progress, coordinate analyses of data and presentation of results at conferences and in publications on behalf of the study group. CONCLUSION: The registry aims to define predictors for optimal medical care and patient-centred treatment outcomes. The ultimate goal of the registry is to generate results that are so relevant to be directly transferred into clinical practice to enhance treatment protocols.

A systematic review and meta-analysis of factors involved in bone flap resorption after decompressive craniectomy.

Decompressive craniectomy (DC) is effective in controlling increasing intracranial pressure determined by a wide range of conditions, mainly traumatic brain injury (TBI) and stroke, and the subsequent cranioplasty (CP) displays potential therapeutic benefit in terms of overall neurological function. While autologous bone flap (ABF) harvested at the time of DC is the ideal material for skull defect reconstruction, it carries several risks. Aseptic bone flap resorption (BFR) is one of the most common complications, often leading to surgical failure. The aim of our study was to systematically review the literature and carry out a meta-analysis of possible factors involved in BFR in patients undergoing ABF cranioplasty after DC. A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. Different medical databases (PubMed, Embase, and Scopus) were screened for eligible scientific reports until April 30th 2021. The following data were collected for meta-analysis to assess their role in BFR: sex, age, the interval time between DC and CP, the presence of systemic factors, the etiology determining the DC, CP surgical time, CP features, VP shunt placement, CP infection. Studies including pediatric patients or with less than 50 patients were excluded. Fifteen studies were included. There was a statistically significant increased incidence of BFR in patients with CPF > 2 compared to patients with CPF ≤ 2 (54.50% and 22.76% respectively, p = 0.010). TBI was a significantly more frequent etiology in the BFR group compared to patients without BFR (61.95% and 47.58% respectively, p < 0.001). Finally, patients with BFR were significantly younger than patients without BFR (39.12 ± 15.36 years and 47.31 ± 14.78 years, respectively, p < 0.001). The funnel plots were largely symmetrical for all the studied factors. Bone flap fragmentation, TBI etiology, and young age significantly increase the risk of bone resorption. Further studies are needed to strengthen our results and to clarify if, in those cases, a synthetic implant for primary CP should be recommended.

Experience and modification of skull base reconstruction results in lower complications rates.

OBJECTIVES: To investigate the efficacy of nasal septum bone flap combined with vascularized pedicle nasoseptal flap (VP-NSF) in the treatment of high-flow cerebrospinal fluid (CSF) leakage in the endonasal endoscopic skull base surgery. METHODS: A total of 156 patients in group A used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater- fascia lata-VP-NSF, and were treated with drainage of the lumbar cistern after surgery, in addition, a total of 94 patients in group B used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater-nasal septal bone flap-VP-NSF, and no lumbar cistern drainage was performed after surgery. Analyzed and compared the differences of postoperative cerebrospinal fluid rhinorrhea, intracranial infection, re-repair, average bed rest time, pulmonary infection and deep venous thrombosis of lower extremities were analyzed and compared in the two groups. RESULTS: In group A, 11 cases of cerebrospinal fluid rhinorrhea occurred after operation. In addition, 15 cases developed intracranial infection. During this period, there were 20 cases of pulmonary infection and 3 cases of deep venous thrombosis of lower extremities. In group B, there were 1 case of cerebrospinal fluid rhinorrhea (P < 0.05), 2 cases of intracranial infection (P < 0.05), 2 cases of pulmonary infection (P < 0.05), and 0 case of deep venous thrombosis of lower extremities (P > 0.05). CONCLUSION: Nasal septum bone flap combined with VP-NSF is effective in the treatment of high-flow CSF leaks in the endonasal endoscopic skull base surgery, which can avoid postoperative lumbar cistern drainage and is worth popularizing.

Effects of cruciate embedding fascia-bone flap technique on grade II-III cerebral spinal fluid leak in endoscopic endonasal surgery.

BACKGROUND: Cerebral spinal fluid (CSF) leak remains an important issue in endoscopic endonasal surgery (EES). A standard protocol for skull base closure has not yet been established, and the application of rigid buttress has not been given sufficient attention. To emphasize the functions of support and fixation from rigid buttress in reconstruction, we introduced the cruciate embedding fascia-bone flap (CEFB) technique using autologous bone graft to buttress the fascia lata attachment to the partially sutured skull base dural defect and evaluated its efficacy in a consecutive case series of grade II-III CSF leaks in EES. METHODS: Data from consecutive patients diagnosed with sellar region lesions with grade II-III CSF leaks during EES were collected from May 2015 to May 2020. Skull base reconstructions were performed with the CEFB or the conventional pedicle vascularized nasoseptal flap (PNSF). Related clinical data were analysed. The combined use of the CEFB and PNSF was applied to an additional supplemental case series of patients with grade III leak and multiple high-risk factors. RESULTS: There were 110 and 65 patients included in the CEFB and PNSF groups, respectively. The CEFB demonstrated similar effects on the incidence of postoperative CSF leak (2.7%), intracranial infection (4.5%), and lumbar drainage (LD) placement (5.5%) as PNSF (3.1%, 3.1%, and 6.2%), but with less epistaxis (CEFB: 0%, PNSF: 6.2%) and nasal discomforts (CEFB: 0%, PNSF: 7.7%). The LD duration (CEFB: 6.67 ± 2.16 days, PNSF: 10.50 ± 2.38 days), bed-stay time (CEFB: 5.74 ± 1.58 days, PNSF: 8.83 ± 3.78 days) and hospitalization time (CEFB: 10.49 ± 5.51 days, PNSF: 13.58 ± 5.50 days) were shortened in the CEFB group. The combined use of CEFB and PNSF resulted in 0 postoperative CSF leaks in the supplemental case series of 23 highly susceptible patients. CONCLUSION: This study suggested that the new CEFB technique has the potential to prevent postoperative CSF leak in EES. The results indicated that it can be used effectively without PNSF in suitable cases or applied in addition to a PNSF with high compatibility when necessary. Its effectiveness should be further verified with a larger cohort and better design in the next step. Trial Registration Current Controlled Trials ChiCTR2100044764 (Chinese Clinical Trial Registry); date of registration: 27 March 2020. Retrospectively registered.

Posterior vault "free-floating" bone flap: indications, technique, advantages, and drawbacks.

BACKGROUND: The enlargement of the posterior cranial fossa volume is considered one of the main steps of the surgical management of children with multiple sutures craniosynostosis. Different management options have been proposed including fixed expansive craniotomy, free bone flap craniotomy, and distraction osteogenesis. OBJECTIVES: To review indications to "free bone flap" craniotomy for the posterior fossa expansion, detailing advantages, disadvantages, and complications related to the technique. RESULTS AND CONCLUSIONS: A review of the literature shows that "free bone flap" posterior expansion cranioplasty still has a role, particularly in infants with thin and "honeycomb" structure of the bone, allowing to gain adequate intracranial volume increases and to postpone to a more adequate time surgery aimed at anterior cranial fossa expansion.

Cranial bone flap resorption-pathological features and their implications for clinical treatment.

Cranioplasty following decompressive craniectomy (DC) has a primary complication when using the autologous bone: aseptic bone resorption (ABR). So far, risk factors such as age, number of fragments, and hydrocephalus have been identified but a thorough understanding of the underlying pathophysiology is still missing. The aim of this osteopathological investigation was to gain a better understanding of the underlying processes. Clinical data of patients who underwent surgical revision due to ABR was collected. Demographics, the time interval between craniectomy and cranioplasty, and endocrine serum parameters affecting bone metabolism were collected. Removed specimens underwent qualitative and quantitative histological examination. Two grafts without ABR were examined as controls. Compared to the controls, the typical layering of the cortical and cancellous bone was largely eliminated in the grafts. Histological investigations revealed the coexistence of osteolytic and osteoblastic activity within the necrosis. Bone appositions were distributed over the entire graft area. Remaining marrow spaces were predominantly fibrotic or necrotic. In areas with marrow cavity fibrosis, hardly any new bone tissue was found in the adjacent bone, while there were increased signs of osteoclastic resorption. Insufficient reintegration of the flap may be due to residual fatty bone marrow contained in the bone flap which seems to act as a barrier for osteogenesis. This may obstruct the reorganization of the bone structure, inducing aseptic bone necrosis. Following a path already taken in orthopedic surgery, thorough lavage of the implant to remove the bone marrow may be a possibility, but will need further investigation.

Complications of cranioplasty following decompressive craniectomy for traumatic brain injury: systematic review and meta-analysis.

BACKGROUND: Decompressive craniectomy (DC) is a common neurosurgical intervention for severe traumatic brain injury (TBI), as well as malignant stroke, malignancy and infection. DC necessitates subsequent cranioplasty. There are significant demographic differences between TBI and non-TBI patients undergoing cranioplasty, which may influence their relative risk profiles for infection, aseptic bone flap resorption (aBFR) and re-operation. OBJECTIVE: Perform a meta-analysis to determine the relative infection, aBFR and re-operation risk profiles of TBI patients as compared to other indications for DC. METHODS: A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. PubMed, MEDLINE, EMBASE and Google Scholar were searched until 26/11/2020. Studies detailing rates of infection, re-operation and/or aBFR in specific materials and the post-TBI population were included, while studies in paediatrics or craniosynostosis repair were excluded. RESULTS: Twenty-six studies were included. There was no difference in relative risk of infection between TBI and non-TBI cohorts (RR 0.81, 95% CI 0.57-1.17), with insignificant heterogeneity (I2 = 33%). TBI was a risk factor for aBFR (RR 1.54, 95% CI 1.25-1.89), with no significant heterogeneity (I2 = 13%). TBI was a risk factor for re-operation in the autologous sub-group (RR 1.49, 95% CI 1.05-2.11) but not in the alloplastic sub-group (RR = 0.86, 95% CI 0.34-2.18). Heterogeneity was insignificant (I2 = 11%). CONCLUSION: TBI is a risk factor for aBFR and re-operation following cranioplasty. Use of an alloplastic graft for primary cranioplasty in these patients may partially mitigate this increased risk.

Treatment with endoscopic transnasal resection of hypothalamic pilocytic astrocytomas: a single-center experience.

BACKGROUNDS: Pilocytic astrocytomas (PAs) are World Health Organization (WHO) grade I tumors, which are relatively common, and are benign lesions in children. PAs could originate from the cerebellum, optic pathways, and third ventricular/hypothalamic region. Traditional various transcranial routes are used for hypothalamic PAs (HPAs). However, there are few studies on hypothalamic PAs treated through the endoscopic endonasal approach (EEA). This study reports the preliminary experience of the investigators and results with HPAs via expanded EEAs. METHODS: All patients with HPAs, undergone EEA in our hospital from 2017 to 2019, were retrospectively reviewed. The demographic data, clinical symptoms, complications, skull base reconstruction, prognosis, and endocrinological data were all recorded and analyzed in detail. RESULTS: Finally, five female patients were enrolled. The average age of patients was 28.6 ± 14.0. All patients had complaints about their menstrual disorder. One patient had severe bilateral visual impairment. Furthermore, only one patient suffered from severe headache due to acute hydrocephalus, although there were four patients with headache or dizziness. Four cases achieved gross-total resection, and one patient achieved subtotal resection. Furthermore, there was visual improvement in one patient (case 5), and postoperative worsening of vision in one patient (case 4). However, only one patient had postoperative intracranial infection. None of the patients experienced a postoperative CSF leak, and in situ bone flap (ISBF) techniques were used for two cases for skull base repair. In particular, ISBF combined with free middle turbinate mucosal flap was used for case 5. After three years of follow-up, three patients are still alive, two patients had no neurological or visual symptoms, or tumor recurrence, and one patient had severe hypothalamic dysfunction. Unfortunately, one patient died of severe postoperative hypothalamus reaction, which presented with coma, high fever, diabetes insipidus, hypernatremia and intracranial infection. The other patient died of recurrent severe pancreatitis at one year after the operation. CONCLUSION: Although the data is still very limited and preliminary, EEA provides a direct approach to HPAs with acceptable prognosis in terms of tumor resection, endocrinological and visual outcomes. ISBF technique is safe and reliable for skull base reconstruction.

The storage of skull bone flaps for autologous cranioplasty: literature review.

The use of autologous bone flap for cranioplasty after decompressive craniectomy is a widely used strategy that allows alleviating health expenses. When the patient has recovered from the primary insult, the cranioplasty restores protection and cosmesis, recovering fluid dynamics and improving neurological status. During this time, the bone flap must be stored, but there is a lack of standardization of tissue banking practices for this aim. In this work, we have reviewed the literature on tissue processing and storage practices. Most of the published articles are focused from a strictly clinical and surgical point of view, paying less attention to issues related to tissue manipulation. When bone resorption is avoided and the risk of infection is controlled, the autograft represents the most efficient choice, with the lowest risk of complication. Otherwise, depending on the degree of involvement, the patient may have to undergo new surgery, assuming further risks and higher healthcare costs. Therefore, tissue banks must implement protocols to provide products with the highest possible clinical effectiveness, without compromising safety. With a centralised management of tissue banking practices there may be a more uniform approach, thus facilitating the standardization of procedures and guidelines.

Surgical Treatment of Voluminous Jaw Cysts with a Buccal Plate: A Study of 20 Clinical Cases.

AIM AND OBJECTIVE: The aim of this paper is to present, with a series of clinical cases, some advantages of a modified surgical technique using fixed bone flaps in an approach to voluminous maxillary or mandibular odontogenic cysts (excluding keratocysts) and highlight the positive impact on the healing of mucus and bone tissues. BACKGROUND: The surgical approach of the enucleation of voluminous maxillary cysts is generally realized with a subtractive osteoplasty. The major problem with this kind of procedure is frequent fibrous healing (or scar formation) of the cavity due to mucosal invagination, especially for large lesions more than 2 cm in diameter. Several techniques have been proposed to limit these side effects. Very contrasting results have been observed in the techniques with graft or exogenous materials, and the scarring effects on mucus and bone tissues are poorly described. In situations where a vestibular cortical bone remains, our modification of the former technique is the use of this bone like a repositioned flap. TECHNIQUE: The present study is a cases series and was carried out on 20 adult patients with maxillary or mandibular cystic lesions larger than 25 mm. For all the patients, our modified technique consisted of using a bone flap to expose more widely the site and to carry out the enucleation of the cyst. Repositioning the flap in the final stage of the operation with osteosynthesis material allowed controlled mucosal and bone healing confirmed by clinical and radiographic follow-up. CONCLUSION: In all cases of our study, no invagination of the soft tissues in the cystic cavity was observed and postoperative bone volumes were identical to the initial state. Only minor postoperative complications were observed in three cases. CLINICAL SIGNIFICANCE: A bone flap approach seems to allow a tissue interception, thus better control of mucosal and bone healing, which is borne out by the clinical and radiographic controls 24 months after surgery.

[Medial femoral condyle free flap for reconstruction of carpometacarpal bone defect after giant cell tumour of tendon synovial sheath resection]. / Transfert osseux libre de condyle fémoral médial pour la reconstruction d'une perte de substance osseuse carpo-métacarpienne après résection d'une tumeur à cellule géante des gaines synoviale.

We report the case of a 23-year-old patient treated for a large giant cell tumour of the synovial sheaths of the ulnar edge of the hand and wrist invading the triquetrum, the hamatum, the ulnar part of the capitate as well as the bases of the 3rd, 4th and 5th metacarpals and the floor of the Guyon's canal and the carpal tunnel. A monobloc resection was performed in a healthy margin ; the loss of bone substance was 7×3.5cm. We performed a bone reconstruction using a cortico-cancellous medial femoral condyle free flap of 8×4cm. Postoperative follow-up was uneventful and bone consolidation was achieved at 2,5 months postoperatively. The cortico-cancellous medial femoral condyle free flap is an interesting option for treating small and medium size bone loss in the hand and wrist. Its use in its pure bone form or in its chimeric form with muscle, cartilage or skin opens up a wide range of choices for the reconstructive surgeon.