Surgical management of a temporal meningoencephalocele with a patient-specific combined craniofossa prosthesis: illustrative case.

BACKGROUND: Meningoencephaloceles can originate through any defect in the cranial bones, including the skull base. They can be completely asymptomatic or present with typical symptoms such as headaches, seizures, or meningitis. OBSERVATIONS: The authors present the case of a 54-year-old female who presented with right-sided ear and temporomandibular joint (TMJ) pain. Computed tomography showed a large lytic lesion of the squamous part of the temporal bone with cortical bone destruction, extending to the mandibular fossa. Magnetic resonance imaging demonstrated a temporal bone meningoencephalocele. The patient underwent resection, dural repair, and multilayer reconstruction with a patient-specific three-dimensional-printed titanium combined craniofossa prosthesis. LESSONS: To the authors' knowledge, this is the first case report of TMJ pain associated with a temporal meningoencephalocele. The exact location and extension of the lesion determine the surgical approach and need for reconstruction in temporal bone meningoencephaloceles. In cases of destruction of the mandibular fossa, a patient-specific combined craniofossa prosthesis is recommended to reconstruct the bone defect. https://thejns.org/doi/10.3171/CASE24132.

Virtual reconstruction of orbital defects using Gaussian process morphable models.

PURPOSE: The conventional method to reconstruct the bone level for orbital defects, which is based on mirroring and manual adaptation, is time-consuming and the accuracy highly depends on the expertise of the clinical engineer. The aim of this study is to propose and evaluate an automated reconstruction method utilizing a Gaussian process morphable model (GPMM). METHODS: Sixty-five Computed Tomography (CT) scans of healthy midfaces were used to create a GPMM that can model shape variations of the orbital region. Parameter optimization was performed by evaluating several quantitative metrics inspired on the shape modeling literature, e.g. generalization and specificity. The reconstruction error was estimated by reconstructing artificial defects created in orbits from fifteen CT scans that were not included in the GPMM. The developed algorithms utilize the existing framework of Gaussian process morphable models, as implemented in the Scalismo software. RESULTS: By evaluating the proposed quality metrics, adequate parameters are chosen for non-rigid registration and reconstruction. The resulting median reconstruction error using the GPMM was lower (0.35 ± 0.16 mm) compared to the mirroring method (0.52 ± 0.18 mm). In addition, the GPMM-based reconstruction is automated and can be applied to large bilateral defects with a median reconstruction error of 0.39 ± 0.11 mm. CONCLUSION: The GPMM-based reconstruction proves to be less time-consuming and more accurate than reconstruction by mirroring. Further validation through clinical studies on patients with orbital defects is warranted. Nevertheless, the results underscore the potential of GPMM-based reconstruction as a promising alternative for designing patient-specific implants.

Reconstruction of Craniomaxillofacial Bone Defects with 3D-Printed Bioceramic Implants: Scoping Review and Clinical Case Series.

Reconstruction of craniomaxillofacial bone defects using 3D-printed hydroxyapatite (HA) bioceramic patient-specific implants (PSIs) is a new technique with great potential. This study aimed to investigate the advantages, disadvantages, and clinical outcomes of these implants in craniomaxillofacial surgeries. The PubMed and Embase databases were searched for patients with craniomaxillofacial bone defects treated with bioceramic PSIs. Clinical outcomes such as biocompatibility, biomechanical properties, and aesthetics were evaluated and compared to those of commonly used titanium or poly-ether-ether-ketone (PEEK) implants and autologous bone grafts. Two clinical cases are presented to illustrate the surgical procedure and clinical outcomes of HA bioceramic PSIs. Literature review showed better a biocompatibility of HA PSIs than titanium and PEEK. The initial biomechanical properties were inferior to those of autologous bone grafts, PEEK, and titanium but improved when integrated. Satisfactory aesthetic results were found in our two clinical cases with good stability and absence of bone resorption or infection. Radiological signs of osteogenesis were observed in the two clinical cases six months postoperatively. HA bioceramic PSIs have excellent biocompatible properties and imitate natural bone biomechanically and radiologically. They are a well-suited alternative for conventional biomaterials in the reconstruction of load-sharing bone defects in the craniomaxillofacial region.

Congenital Unilateral Zygomaticomaxillomandibular Fusion in a 4-year-old Girl.

Congenital zygomaticomaxillomandibular (ZMM) fusion is an extremely rare and debilitating condition. Fusion of the jaws results in a severe limitation of the mouth opening accompanied by breathing and feeding difficulties. Mandibular fusions to the maxilla, palate, zygoma, and temporal bone are described in literature. We present the case of 4-year-old girl diagnosed with congenital unilateral ZMM fusion. She was treated surgically at 1 year and at 4 and a half years to release the fusion and to improve mouth opening. Second surgery was indicated due to recurrence. Management of young patients with congenital maxillomandibular fusion is challenging. The scarcity of cases makes formulating practice guidelines very difficult. If surgery is performed, the importance of postoperative physical therapy cannot be overstated. The goal of this article is to emphasize the risk of recurrence in ZMM fusion after surgical treatment and importance of regular follow-up.

OrthoCalc: The six degrees of freedom measurement workflow of rotational and displacement changes for maxilla positioning evaluation.

BACKGROUND: This study is undertaken to establish the accuracy and reliability of OrthoCalc, a 3D application designed for the evaluation of maxillary positioning. METHODS: We registered target virtual planned models, maxillary models from pre-operative and post-operative CT scans, and post-operative intra-oral scans to a common reference system, allowing for digital evaluation. To assess rotational changes, we introduced a novel measurement method based on virtual cuboid models. Displacement errors were calculated based on proposed registration matrices. We also compared OrthoCalc to established commercial medical software as a benchmark. RESULTS: Statistical significance calculated showed no significant differences between OrthoCalc and commercial software. the biggest error of 0.04 degree in rotation change was found in the yaw. A maximum displacement change of 0.75 mm was found in the X direction. CONCLUSIONS: Our study validates OrthoCalc as a precise and reliable tool for assessing maxillary position changes with six degrees of freedom in orthognathic surgery, endorsing its clinical utility.

Exploring long-term responses to immune checkpoint inhibitors in recurrent and metastatic head and neck squamous cell carcinoma.

OBJECTIVES: Immune checkpoint inhibitors (ICI) have introduced a new era in the treatment of recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC). Optimal duration for ICI therapy is still unclear and the long-term outcomes and toxicity in patients responding to these therapies warrant further exploration. This study attempts to identify the clinical and biological determinants of a durable response and evaluate outcomes following ICI treatment discontinuation. MATERIALS AND METHODS: A retrospective review of 181 patients treated with ICI for R/M HNSCC was conducted. Long-term responders were defined as patients who sustained disease control at least two years after initiating ICI therapy. We compared clinical and biological characteristics associated with these long-term responders against the broader treatment population. RESULTS: 10 % of R/M HNSCC patients treated with ICIs demonstrated a durable long-term response. Only three relapses (16 %) occurred after discontinuing ICI treatment in this subset, with a median follow-up of 52 months. Upon retreatment with ICI, two attained a documented response. Extended ICI response was observed even with < 2 years of treatment. 74 % of long-term responders experienced immune-related adverse events (irAEs), 37 % of which severe irAEs. Hypothyroidism was the most frequently reported irAEs. The predictive potential of systemic inflammation indices for clinical response appears to be limited. CONCLUSIONS: ICI present an optimistic avenue for HNSCC patients, offering substantial long-term responses. The study suggests that a two-year treatment could be optimal and irAEs, although common, are typically mild.

Accuracy of surgical navigation for patient-specific reconstructions of orbital fractures: A systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to review the recent literature on the technical accuracy of surgical navigation for patient-specific reconstruction of orbital fractures using a patient-specific implant, and to compare surgical navigation with conventional techniques. MATERIALS AND METHODS: A systematic literature search was conducted in PubMed (Medline), Embase, Web of Science, and Cochrane (Core Collection) databases on May 16, 2023. Literature comparing surgical navigation with a conventional method using postoperative three-dimensional computed tomography imaging was collected. Only articles that studied at least one of the following outcomes were included: technical accuracy (angular accuracy, linear accuracy, volumetric accuracy, and degree of enophthalmos), preoperative and perioperative times, need for revision, complications, and total cost of the intervention. MINORS criteria were used to evaluate the quality of the articles. RESULTS: After screening 3733 articles, 696 patients from 27 studies were included. A meta-analysis was conducted to evaluate volumetric accuracy and revision rates. Meta-analysis proved a significant better volumetric accuracy (0.93 cm3 ± 0.47 cm3) when surgical navigation was used compared with conventional surgery (2.17 cm3 ± 1.35 cm3). No meta-analysis of linear accuracy, angular accuracy, or enophthalmos was possible due to methodological heterogeneity. Surgical navigation had a revision rate of 4.9%, which was significantly lower than that of the conventional surgery (17%). Costs were increased when surgical navigation was used. CONCLUSION: Studies with higher MINORS scores demonstrated enhanced volumetric precision compared with traditional approaches. Surgical navigation has proven effective in reducing revision rates compared to conventional approaches, despite increased costs.

Augmented and Virtual Reality for Preoperative Trauma Planning, Focusing on Orbital Reconstructions: A Systematic Review.

BACKGROUND: This systematic review summarizes recent literature on the use of extended reality, including augmented reality (AR), mixed reality (MR), and virtual reality (VR), in preoperative planning for orbital fractures. METHODS: A systematic search was conducted in PubMed, Embase, Web of Science and Cochrane on 6 April 2023. The included studies compared extended reality with conventional planning techniques, focusing on computer-aided surgical simulation based on Computed Tomography data, patient-specific implants (PSIs), fracture reconstruction of the orbital complex, and the use of extended reality. Outcomes analyzed were technical accuracy, planning time, operative time, complications, total cost, and educational benefits. RESULTS: A total of 6381 articles were identified. Four articles discussed the educational use of VR, while one clinical prospective study examined AR for assisting orbital fracture management. CONCLUSION: AR was demonstrated to ameliorate the accuracy and precision of the incision and enable the better identification of deep anatomical tissues in real time. Consequently, intraoperative imaging enhancement helps to guide the orientation of the orbital reconstruction plate and better visualize the precise positioning and fixation of the PSI of the fractured orbital walls. However, the technical accuracy of 2-3 mm should be considered. VR-based educational tools provided better visualization and understanding of craniofacial trauma compared to conventional 2- or 3-dimensional images.

A 16-year retrospective study of vascular anomalies in the head and neck region.

Depending on the diagnostic modality, the classification of vascular anomalies varies and so does the nomenclature. The 'International Society for the Study of Vascular Anomalies' (ISSVA) is the most widely accepted classification in the literature and is mainly based on the radiologic and clinical presentation. The aim of this article is to review the clinical practice of diagnosis and treatment of vascular anomalies in the head and neck region in a university hospital, with special focus on the nomenclature. All patients with a vascular anomaly presenting to the department of oral and maxillofacial surgery were reviewed in a retrospective manner. Nomenclature, diagnostic process, lesion characteristics, treatment and outcome were examined. The lesions were (re)classified according to the ISSVA classification. A total of 185 patients were identified, of which 12.4% (n = 23) had a congenital anomaly. After reclassification, the most common lesions were venous malformations (n = 47, 25.4%), followed by lobular capillary hemangiomas (n = 17, 9.2%). A group of 39 anomalies could not be further specified. One hundred and one patients (54,6%) received treatment, of which 93 were treated surgically (92,1% of treated patients). Endovascular treatment was considered in 41 patients but applied in only eight. This strict selection led to a low a complication rate. We provide an overview of the clinical practice in the management of vascular anomalies in a university hospital. The histology report is a source of miscommunication because clinicians use the ISSVA classification, while pathologists use the WHO classification. Every professional involved should be aware of the differences in classification and nomenclature.

Indications and complications regarding titanium osteosynthesis in pediatric maxillofacial trauma: A scoping review and critical appraisal.

With the advent of biodegradable osteosynthesis material, titanium osteosynthesis for ORIF in pediatric maxillofacial trauma is not as indisputable as before. The aim of this study was to conduct a scoping review to assess the indications, complications of ORIF with titanium osteosynthesis material in pediatric maxillofacial trauma. A systematic search was conducted in PubMed/MEDLINE, Embase, Web of Science, Cochrane Library, gray literature (ICTRP and clinicaltrials.gov) for studies published until April 2022. 3436 studies were screened and finally 13 articles, compromising a sample of 340 pediatric patients were included after full text reading. Reported complications were infection (6.5% of population), malocclusion (5% of population) and dental maleruption (8% of population). Influence on future growth could not be assessed due to short and heterogeneous follow-up periods. Eight of the thirteen studies concluded to a positive and predictable outcome using titanium ORIF for displaced/complex pediatric maxillofacial fractures. Results of this review suggest that titanium ORIF for maxillofacial fractures in the pediatric population is a reliable treatment. The surgeon must be committed to following these patients longitudinally. Interpreting the results should, however, be done with great care, as most articles have a medium to high risk of bias and limited follow-up.

Systemic Antibiotic Prophylaxis in Maxillofacial Trauma: A Scoping Review and Critical Appraisal.

Infection after maxillofacial trauma remains an important complication, with a significant socio-economic impact. While consensus exists that systemic antibiotic prophylaxis reduces the risk of infection in the management of maxillofacial fractures, the type, and duration remain controversial. Therefore, the purpose of this scoping review was to provide an overview of the current evidence that supports the use of prophylactic antibiotics in the treatment of maxillofacial fractures. A comprehensive literature search on 1 January 2022, in PubMed, Web of Science, Embase, and Cochrane, revealed 16 articles. Most studies focused on the duration of systemic antibiotic prophylaxis and compared a one-day to a five-day regimen. Included studies showed considerable variability in design and research aims, which rendered them difficult to compare. Furthermore, a variety of antibiotic regimens were used, and most studies had a short follow-up period and unclear outcome parameters. This scoping review demonstrates the lack of well-constructed studies investigating the type and duration of systemic antibiotic prophylaxis in the treatment of maxillofacial trauma. Based on the included articles, prolonging antibiotic prophylaxis over 24 h for surgically treated fractures does not appear to be beneficial. Furthermore, there is no evidence for its use in conservatively treated fractures. These results should be interpreted with caution since all included studies had limitations.

Value of six comorbidity scales for predicting survival of patients with primary surgery for oral squamous cell carcinoma.

BACKGROUND: Comorbidities influence treatment outcome of oral squamous cell carcinoma (OSCC). This study compared the predictive performance of six comorbidity scales for overall survival after surgery for OSCC. METHODS: We retrospectively analyzed OSCC patients, surgically treated at an academic center in Belgium between January 01, 2000 and January 01, 2020. Validity of the scales was evaluated using the area under the curve (AUC) of receiver operating characteristic curves. RESULTS: Three hundred and twenty three patients were included. Elixhauser Comorbidity Index (AUC = 0.74, 95% CI: 0.55-0.92; AUC = 0.73, 95% CI: 0.55-0.80), modified Elixhauser Comorbidity Index (AUC = 0.72, 95% CI: 0.54-0.91; AUC = 0.69, 95% CI: 0.51-0.77), and Combined Comorbidity Index (AUC = 0.76, 95% CI: 0.58-0.84; AUC = 0.76, 95% CI: 0.59-0.84) were meaningful predictors for 2 and 5-year survival, respectively. CONCLUSION: Selected comorbidity scales were capable of predicting overall survival for OSCC patients 2 and 5 years after primary surgery.

Tough Photo-Cross-Linked PCL-Hydroxyapatite Composites for Bone Tissue Engineering.

Acrylate-based photo-cross-linked poly(ε-caprolactone) (PCL) tends to show low elongation and strength. Incorporation of osteo-inductive hydroxyapatite (HAp) further enhances this effect, which limits its applicability in bone tissue engineering. To overcome this, the thiol-ene click reaction is introduced for the first time in order to photo-cross-link PCL composites with 0, 10, 20, and 30 wt % HAp nanoparticles. It is demonstrated that the elongation at break and ultimate strength increase 10- and 2-fold, respectively, when the photopolymerization mechanism is shifted from a radical chain-growth (i.e., acrylate cross-linking) toward a radical step-growth polymerization (i.e., thiol-ene cross-linking). Additionally, it is illustrated that osteoblasts can attach to and proliferate on the surface of the photo-cross-linked PCL-HAp composites. Finally, the incorporation of HAp nanoparticles is shown to reduce the ALP activity of osteoblasts. Overall, thiol-ene cross-linked PCL-HAp composites can be considered as promising potential materials for bone tissue engineering.

Biomechanical evaluation of the human mandible after temporomandibular joint replacement under different biting conditions.

Temporomandibular joint (TMJ) replacement with an implant is only used when all other conservative treatments fail. Despite the promising short-term results, the long-term implications of TMJ replacement in masticatory function are not fully understood. Previous human and animal studies have shown that perturbations to the normal masticatory function can lead to morphological and functional changes in the craniomaxillofacial system. A clearer understanding of the biomechanical implications of TMJ replacement in masticatory function may help identify design shortcomings that hinder their long-term success. In this study, patient-specific finite element models of the intact and implanted mandible were developed and simulated under four different biting tasks. In addition, the impact of re-attaching of the lateral pterygoid was also evaluated. The biomechanics of both models was compared regarding both mandibular displacements and principal strain patterns. The results show an excessive mediolateral and anteroposterior displacement of the TMJ implant compared to the intact joint in three biting tasks, namely incisor (INC), left moral (LML), and right molar (RML) biting. The main differences in principal strain distributions were found across the entire mandible, most notably from the symphysis to the ramus of the implanted side. Furthermore, the re-attachment of the lateral pterygoid seems to increase joint anteroposterior displacement in both INC, LML and RML biting while reducing it during LGF. Accordingly, any new TMJ implant design must consider stabilising both mediolateral and anteroposterior movement of the condyle during biting activities and promoting a more natural load transmission along the entire mandible.

Complications Following One-Stage Versus Two-Stage Surgical Treatment of Transverse Maxillary Hypoplasia.

PURPOSE: Contemporary literature suggests a similar transverse stability of a surgical-assisted rapid palatal expansion and a segmented Le Fort I osteotomy. The aim of this study was to compare postoperative complications of 1-stage (segmental maxillary osteotomy) and 2-stage (surgical-assisted rapid palatal expansion followed by Le Fort I osteotomy) treated patients to determine the preferred treatment strategy. MATERIALS AND METHODS: This retrospective study included 74 consecutive patients (age range: 14 - 57 years; 36 males, 38 females) with a moderate transverse maxillary hypoplasia: 32 patients were treated in a 1-stage protocol and 42 in a 2-stage protocol with a postoperative follow-up of at least 1 year. Dental complications such as loss of teeth, gingival dehiscence, periodontal bone loss, apical root resorption, and surgical complications such as pain, hemorrhage, altered neurosensitivity, wound infection, aseptic necrosis were analyzed. Univariate analysis consisted of a generalized linear model with logit link or Fisher exact test. RESULTS: No significant difference was found for group characteristics except for longer orthodontic treatment time in the 2-stage group. Incidence and severity of complications were comparable for the 1-stage and 2-stage patients. Only overall pain was significantly greater in the 2-stage patient group (P = .038). CONCLUSIONS: Considering a similar complication rate and transversal stability, the choice between 1-stage and 2-stage approach for patients with a moderate transverse maxillary hypoplasia should be patient specific.

A novel fully automatic design approach of a 3D printed face specific mask: Proof of concept.

The use of high quality facemasks is indispensable in the light of the current COVID pandemic. This study proposes a fully automatic technique to design a face specific mask. Through the use of stereophotogrammetry, computer-assisted design and three-dimensional (3D) printing, we describe a protocol for manufacturing facemasks perfectly adapted to the individual face characteristics. The face specific mask was compared to a universal design of facemask and different filter container's designs were merged with the mask body. Subjective assessment of the face specific mask demonstrated tight closure at the nose, mouth and chin area, and permits the normal wearing of glasses. A screw-drive locking system is advised for easy assembly of the filter components. Automation of the process enables high volume production but still allows sufficient designer interaction to answer specific requirements. The suggested protocol can be used to provide more comfortable, effective and sustainable solution compared to a single use, standardized mask. Subsequent research on printing materials, sterilization technique and compliance with international regulations will facilitate the introduction of the face specific mask in clinical practice as well as for general use.

Three-dimensional characterisation of the globe position in the orbit.

PURPOSE: Current methods to analyse the globe position, including Hertel exophthalmometry and computed tomography (CT), are limited to the axial plane and require the lateral orbital rim and cornea as landmarks. This pilot study aimed to design a method to measure the position of the globe in the axial, coronal and sagittal plane and independent from orbital bony and corneal references. METHODS: With the aid of three-dimensional CT reconstruction technology, we determined the globe position in the orbit based on the centre of the globe. Method validation was performed using data of consecutive orbital CT scans from the control group and from the patients with Graves' orbitopathy who underwent orbital decompression surgery with removal of the lateral orbital margin. RESULTS: The inter- and intra-observer reliability was excellent with a high intraclass correlation coefficient (> 0.99, 95% CI [0.97; 1.00]). In the decompressed orbits, there was a statistically significant globe position shift along the anterior-posterior axis (P = 0.0005, 95% CI [0.63; 3.66]), but not along the medial-lateral and superior-inferior axis. CONCLUSION: The 3D CT method can accurately and reliably characterise the globe position shift in the three dimensions without using orbital and corneal anatomical landmarks. The method can be useful to determine the globe shift in proptosis, enophthalmos, hypoglobus and hyperglobus, even in the presence of strabismus and orbital bone defects.

New Technologies in Rhinoplasty: A Comprehensive Workflow for Computer-assisted Planning and Execution.

Rhinoplasty in facial cleft patients is among the most challenging types of reconstructive facial surgery due to its variability. Advances in 3-dimensional imaging enable improved preoperative assessment in rhinoplasty. In complex cases with bony support irregularities and asymmetry, it is rational to initiate planning with reconstruction of the aberrant substructure (ie, "bottom-up" planning) rather than starting the surgical design with soft-tissue morphing. We present a new comprehensive workflow in which novel advanced technologies are implemented to perform "bottom-up" computer-assisted planning and execution in complex rhinoplasty cases. This workflow enables meticulous planning, use of grafting templates, and 3-dimensional-guided osteotomies with integration of piezotome and intraoperative navigation. Previous reports separately discuss some of these innovations. However, greater benefit lies in the combination of these techniques, with emphasis on preoperative computer analysis, virtual planning, and transfer to the operation theater. Surgeons are seeking new ways to enhance minimally invasive approaches and to obtain predictable and favorable clinical results. The presently introduced workflow allows clinicians to plan complex cases in a simple, effective, and safe manner, with the combination of different techniques to produce consistent results.