The Shunt Valve Recession Technique as a Neuroplastic Surgery Adjunct in Complex and High-Risk Shunt Revisions: Technical Note and Case Series.

BACKGROUND AND OBJECTIVES: Ventricular shunting is one of the most common procedures in neurosurgery. However, complications and revisions are frequent. Patients requiring multiple revisions often suffer secondary issues with scalp healing over hardware. Many common ventricular shunt valves have an obligate thickness that creates a visible protrusion and can potentially cause local tissue ischemia and breakdown in the setting of repeated surgery. The authors present a simple technique for recessing the shunt valve into the underlying bone to alleviate protrusion in high-risk cases. Three example cases utilizing this technique are presented. METHODS: The skull directly underlying the planned valve site is uniformly recessed with a cutting burr several millimeters as desired while maintaining the inner cortical bone layer. The valve is fixed with standard cranial plating hardware. EXPECTED OUTCOMES: Three patients are reported who underwent shunt valve recession as an adjunct to their shunt revision with neuroplastic surgery assistance. All patients had undergone multiple prior surgeries that had resulted in thin and high-risk fragile scalp. In 1 patient, the prior valve was eroding through the scalp before the described revision. All patients had satisfactory cosmetic outcomes, and there were no revisions in the 2-month follow-up period. DISCUSSION: Complex and high-risk ventricular shunt patients should be considered for shunt valve recession into the bone to reduce wound-related complications and enhance healing. This is a technically simple, safe, and effective technique to include as a neuroplastic adjunct.

Skull and Scalp En-Bloc Harvest Protects Calvarial Perfusion: A Cadaveric Study.

BACKGROUND: Calvarial defects are severe injuries that can result from a wide array of etiologies. Reconstructive modalities for these clinical challenges include autologous bone grafting or cranioplasty with biocompatible alloplastic materials. Unfortunately, both approaches are limited by factors such as donor site morbidly, tissue availability, and infection. Calvarial transplantation offers the potential opportunity to address skull defect form and functional needs by replacing "like-with-like" tissue but remains poorly investigated. METHODS: Three adult human cadavers underwent circumferential dissection and osteotomy to raise the entire scalp and skull en-bloc. The vascular pedicles of the scalp were assessed for patency and perfused with color dye, iohexol contrast agent for computed tomography (CT) angiography, and indocyanine green for SPY-Portable Handheld Imager assessment of perfusion to the skull. RESULTS: Gross changes were appreciated to the scalp with color dye, but not to bone. CT angiography and SPY-Portable Handheld Imager assessment confirmed perfusion from the vessels of the scalp to the skull beyond midline. CONCLUSION: Calvarial transplantation may be a technically viable option for skull defect reconstruction that requires vascularized composite tissues (bone and soft tissue) for optimal outcomes.

Discussion on: "Let's Smarten Up: Smart Devices and the Internet of Things, an Untapped Resource for Innovation in Craniofacial Surgery".

Prior to Dr. Paul Tessier's teachings in the 1960's, many neurosurgeons and craniofacial surgeons took shortcuts and employed alloplastic materials fraught with complication, and soon thereafter, both surgical specialties moved the pendulum towards the side of bone grafts being the gold standard for neurosurgical reconstruction and the art of cranioplasty. But now half a century later, neuroplastic surgery is moving the pendulum the other way. Without a doubt, the brain is a critical organ that needs some form of modulation as opposed to replacement. The intervention delivered can be in the form of electricity, light, medicine, etc. Regardless of the medium, it needs to be housed somewhere. And there is no better real estate than to be housed within a sterile alloplastic case with embedded smart technologies; in a way that prevents obvious, visual deformity. For example, it would be naïve to think that the future of embedded neurotechnologies will one day be housed safely and dependably within one's own bone flap. Hence, moving forward, time-tested alloplastic materials will become the new gold standard for cranioplasty reconstruction as the world starts to welcome a generation of smart cranial devices; some of which may house Bluetooth-connected, Wifi-enabled, MRI-compatible pumps to perform convection-enhanced delivery of time-tested medicines - thereby forever changing the way we approach chronic neurological disease and the forever-obstructing, blood-brain barrier. As this happens, I feel confident saying that both Tessier and Cushing are somewhere applauding and smiling on these efforts.

Skull and Scalp En-Bloc Harvest Protects Calvarial Perfusion: A Cadaveric Study.

BACKGROUND: Calvarial defects are severe injuries that can result from a wide array of etiologies. Reconstructive modalities for these clinical challenges include autologous bone grafting or cranioplasty with biocompatible alloplastic materials. Unfortunately, both approaches are limited by factors such as donor site morbidly, tissue availability, and infection. Calvarial transplantation offers the potential opportunity to address skull defect form and functional needs by replacing "like-with-like" tissue but remains poorly investigated. METHODS: Three adult human cadavers underwent circumferential dissection and osteotomy to raise the entire scalp and skull en-bloc. The vascular pedicles of the scalp were assessed for patency and perfused with color dye, iohexol contrast agent for computed tomography (CT) angiography, and indocyanine green for SPY-Portable Handheld Imager assessment of perfusion to the skull. RESULTS: Gross changes were appreciated to the scalp with color dye, but not to bone. CT angiography and SPY-Portable Handheld Imager assessment confirmed perfusion from the vessels of the scalp to the skull beyond midline. DISCUSSION/CONCLUSION: Calvarial transplantation may be a technically viable option for skull defect reconstruction that requires vascularized composite tissues (bone and soft tissue) for optimal outcomes.

Special Considerations in Face Transplantation: A Systematic Review.

ABSTRACT: Vascularized composite allotransplantation of the face is an exceedingly complex procedure, requiring extensive planning and surgical precision in order to successfully manage patients with facial disfigurements. This review aims to present an overview of the salient anatomic considerations in facial transplantation, as well as give attention to unique patient populations and special considerations.A literature review was performed in search of articles pertaining to considerations in facial transplantation using the databases PubMed, Web of Science, and Cochrane. Articles selected for further review included full-text articles with an emphasis on specific anatomic defects and how they were addressed in the transplant process, as well as management of special patient populations undergoing facial transplantation. In total, 19 articles were deemed appropriate for inclusion.The use of computer-assisted technologies for the planning portion of the procedure, as well as intraoperative efficiency, has yielded favorable results and can be considered as part of the operative plan. The ultimate outcome is dependent upon the synchronization of subunits of the allograft and the desired functional outcomes, including osseous, ocular, oral, and otologic considerations. Management of specific pathology and subgroups of patients are critical aspects. Although pediatric face transplantation has not yet been performed, it is a likely a future step in the evolution of this procedure.When performing a face transplantation, many components must be considered pre-, intra-, and post-operatively. This systematic review presents specific anatomic considerations, as well as information about special patient populations within this crosssection of multidisciplinary microsurgery, psychiatry, and transplant immunology.

Cranioplasty With Customized Craniofacial Implants and Intraoperative Resizing for Single-Stage Reconstruction Following Oncologic Resection of Skull Neoplasms.

BACKGROUND: Craniectomies requiring skull reconstruction are indicated following oncological resection of masses involving the underlying brain and/or skull. Immediate cranioplasties have previously been performed using suboptimal hand-bending or molding techniques using "off - the - shelf" products. Today with computer - aided design, customized craniofacial implants have become widely available for personalized reconstruction of resected bone and soft tissue. We present here the largest series to date of single stage reconstruction using alloplastic biomaterials in consecutive patient series with oversized customized implants. METHODS: A single-surgeon, retrospective, 8-year study was conducted on all consecutive patients undergoing single stage cranioplasty with prefabricated implants using a myriad of biomaterials. All outcomes were analyzed in detail and compared with previous studies utilizing similar alloplastic implants. RESULTS: In total, 56 patients underwent resection of skull neoplasms and subsequent cranioplasty reconstruction using customized implants. The most common neoplasms were meningiomas (39%). The most common complications seen among patients were dehiscence - (7%), and extrusion of implant - (3.5%). There was no significant difference in the incidence of postoperative complications between patients who had postoperative chemotherapy/radiotherapy versus those that did not (22.2% versus 13.1%, P = 0.39). One-year follow-up revealed acceptable cranial contour and symmetry in all 56 cases. CONCLUSIONS: This is a consecutive case series of prefabricated single-stage cranioplasty, following resection of brain tumors with bone extension or skull bone neoplasm, demonstrating excellent results with regards to safety and patient satisfaction. There are several advantages such as comprehensive resection and reconstruction plan using 3D models, shorter operative time, and better restoration of complex anatomy.

Cranioplasty Outcomes From 500 Consecutive Neuroplastic Surgery Patients.

BACKGROUND: Cranioplasty is critical to cerebral protection and restoring intracranial physiology, yet this procedure is fraught with a high risk of complications. The field of neuroplastic surgery was created to improve skull and scalp reconstruction outcomes in adult neurosurgical patients, with the hypothesis that a multidisciplinary team approach could help decrease complications. OBJECTIVE: To determine outcomes from a cohort of cranioplasty surgeries performed by a neuroplastic surgery team using a consistent surgical technique and approach. METHODS: The authors reviewed 500 consecutive adult neuroplastic surgery cranioplasties that were performed between January 2012 and September 2020. Data were abstracted from a prospectively maintained database. Univariate analysis was performed to determine association between demographic, medical, and surgical factors and odds of revision surgery. RESULTS: Patients were followed for an average of 24 months. Overall, there was a reoperation rate of 15.2% (n = 76), with the most frequent complications being infection (7.8%, n = 39), epidural hematoma (2.2%, n = 11), and wound dehiscence (1.8%, n = 9). New onset seizures occurred in 6 (1.2%) patients.Several variables were associated with increased odds of revision surgery, including lower body mass ratio, 2 or more cranial surgeries, presence of hydrocephalus shunts, scalp tissue defects, large-sized skull defect, and autologous bone flaps. importantly, implants with embedded neurotechnology were not associated with increased odds of reoperation. CONCLUSIONS: These results allow for comparison of multiple factors that impact risk of complications after cranioplasty and lay the foundation for development of a cranioplasty risk stratification scheme. Further research in neuroplastic surgery is warranted to examine how designated centers concentrating on adult neuro-cranial reconstruction and multidisciplinary collaboration may lead to improved cranioplasty outcomes and decreased risks of complications in neurosurgical patients.

The Impact of Hydrocephalus Shunt Devices on Quality of Life.

BACKGROUND: Despite advances in hydrocephalus shunt technology and improvement in hydrocephalus management, many patients have chronic disability and require multiple surgeries throughout their lifetime. There is limited data from patients' perspective regarding the impact of shunt devices on quality-of-life. METHODS: A cross-sectional survey was developed to evaluate the impact of shunt devices on patient quality-of-life. The survey was distributed via social media platforms of the Hydrocephalus Association, and patients self-selected to anonymously complete the online questionnaire. A literature review was performed to contextualize the findings from the survey. RESULTS: A total of 562 survey responses were obtained from a network encompassing 35,000 members. The mean age was 30 years old (0.5-87), and 65% identified as female. Eighty one percent underwent at least 1 shunt revision surgery, with a reported average of 10 shunt revision surgeries per patient (1-200 surgeries). Occlusion, shunt migration and infection were the leading causes for revision at 60%, 47%, and 35%, respectively. In addition, 72% of patients reported pain and discomfort from the device, and 68% expressed avoidance of certain activities due to "fear of bumping shunt." Despite numerous articles discussing shunt technology, a review of the literature indicated a paucity of studies specifically evaluating the burden of shunt devices from a patient/caregiver perspective. CONCLUSIONS: The findings from this study suggest long-term physical and psychosocial burden associated with shunt devices. Importantly, this study highlights the need for concerted efforts to develop validated tools to study patient reported outcomes as it relates to neurocranial implanted devices.

Translucent Customized Cranial Implants Made of Clear Polymethylmethacrylate: An Early Outcome Analysis of 55 Consecutive Cranioplasty Cases.

BACKGROUND: Large skull reconstruction, with the use of customized cranial implants, restores cerebral protection, physiologic homeostasis, and one's preoperative appearance. Cranial implants may be composed of either bone or a myriad of alloplastic biomaterials. Recently, patient-specific cranial implants have been fabricated using clear polymethylmethacrylate (PMMA), a visually transparent and sonolucent variant of standard opaque PMMA. Given the new enhanced diagnostic and therapeutic applications of clear PMMA, we present here a study evaluating all outcomes and complications in a consecutive patient series. METHODS: A single-surgeon, retrospective, 3-year study was conducted on all consecutive patients undergoing large cranioplasty with clear PMMA implants (2016-2019). Patients who received clear PMMA implants with embedded neurotechnologies were excluded due to confounding variables. All outcomes were analyzed in detail and compared with previous studies utilizing similar alloplastic implant materials. RESULTS: Fifty-five patients underwent cranioplasty with customized clear PMMA implants. Twenty-one (38%) were performed using a single-stage cranioplasty method (ie, craniectomy and cranioplasty performed during the same operation utilizing a prefabricated, oversized design and labor-intense, manual modification), whereas the remaining 34 (62%) underwent a standard, 2-stage reconstruction (craniectomy with a delayed surgery for cranioplasty and minimal-to-no implant modification necessary). The mean cranial defect size was 101.8 cm. The mean follow-up time was 9 months (range, 1.5-39). Major complications requiring additional surgery occurred in 7 patients (13%) consisting of 2 (4%) cerebrospinal fluid leaks, 2 (4%) epidural hematomas, and 3 (4%) infections. In addition, 3 patients developed self-limiting or nonoperative complications including 2 (4%) with new onset seizures and 1 (2%) with delayed scalp healing. CONCLUSIONS: This is the first reported consecutive case series of cranioplasty reconstruction using customized clear PMMA implants, demonstrating excellent results with regard to ease of use, safety, and complication rates well below published rates when compared with other alloplastic materials. Clear PMMA also provides additional benefits, such as visual transparency and sonolucency, which is material specific and unavailable with autologous bone. Although these early results are promising, further studies with multicenter investigations are well justified to evaluate long-term outcomes.

Bilateral Versus Unilateral Cranialization in the Management of a Breached Frontal Sinus.

BACKGROUND: Frontal sinus breach during craniotomy may occur inadvertently or intentionally. Management of a breached frontal sinus is controversial as numerous operative techniques have been described. Frontal sinus breach may result in life-threatening complications, require additional surgeries, and increase the risk for long-term infectious sequelae. A literature review found a paucity of neurosurgical reports examining breached frontal sinus management or specific analyses of unilateral versus bilateral frontal sinus cranialization. OBJECTIVE: A frontal sinus cranialization technique employed for patients involving frontal sinus breach and analyze outcomes managed with bilateral versus unilateral cranialization was presented in this study. METHODS: A retrospective review of outcomes was performed using our Institutional Review Board-approved surgical case database between September 2012 and September 2018. RESULTS: Thirty-three frontal sinus cranializations following frontal sinus breach were identified. Average follow-up time was 25 months. A statistically significant difference in postoperative infections was observed in patients with a history of previous cranial surgery who underwent unilateral compared to bilateral frontal sinus cranialization. CONCLUSION: These results suggest surgeons performing craniotomy or consulted intraoperatively for suspected frontal sinus breach should have a high suspicion for breached frontal sinus and a low threshold for frontal sinus cranialization. Furthermore, when performing frontal sinus cranialization, surgeons should consider performing bilateral, instead of unilateral, cranialization in patients with a history of previous craniotomy as bilateral cranialization was shown to decrease the risk of postoperative infection.

Risk of Complications in Primary Versus Revision-Type Cranioplasty.

INTRODUCTION: Cranioplasty (CP) is a multifaceted procedure in a heterogenous patient population, with a high risk for complication. However, no previous large-scale studies have compared outcomes in primary (ie, first attempt) CP versus revision CP (ie, following previous attempts). The authors, therefore, analyzed long-term outcomes of 506 consecutive primary and revision CPs, performed by a single surgeon. METHODS: All CPs performed between 2012 and 2019 were analyzed under IRB protocol approval. Surgeries were categorized as either primary (no previous CP; n = 279) or revision CP (at least one previous CP; n = 227). Complications were defined as either major or minor. Subgroup analyses investigated whether or not CP complication risk directly correlated with the number of previous neuro-cranial surgeries and/or CP attempts. RESULTS: The primary CP group experienced a major complication rate of 9% (26/279). In comparison, the revision CP group demonstrated a major complication rate of 32% (73/227). For the revision CP group, the rate of major complications rose with each additional surgery, from 4% (1 prior surgery) to 17% (2 prior surgeries) to 39% (3-4 prior surgeries) to 47% (≥5 prior surgeries). CONCLUSION: In a review of 506 consecutive cases, patients undergoing revision CP had a 3-fold increase in incidence of major complications, as compared to those undergoing primary CP. These results provide critical insight into overall CP risk stratification and may guide preoperative risk-benefit discussions. Furthermore, these findings may support a center-of-excellence care model, particularly for those patients with a history of previous neuro-cranial surgeries and/or CP attempts.

Investigation of a Valve-Agnostic Cranial Implant for Adult Hydrocephalus Patients Requiring Ventriculoperitoneal Shunting.

INTRODUCTION: Currently, the most effective treatment strategy for adults with hydrocephalus involves cerebrospinal fluid diversion by means of a shunt system, most commonly ventriculoperitoneal shunts (VPS). Ventriculoperitoneal shunting is associated with high complication and/or revision rates, in part due to the high-profile programmable valve designs. Thus, the valve-agnostic cranial implant (VACI) was designed and investigated as a safe and effective method of reducing the valve's high profile and is currently undergoing clinical trials. As such, the objective of this study was to collate preliminary, multi-institutional data of early outcomes using a VACI approach for patients requiring VPS by way of an Institutional Review Board approved registry. METHODS: A total of 25 adult patients across 4 institutions and 6 surgeons underwent VACI placement for VPS based on preoperative evaluation and perceived benefit. Patient demographics, operative details, and preliminary outcomes are presented here. RESULTS: Valve-agnostic cranial implant placement via a limited size craniectomy at time of shunt revision was performed with no adverse events. Over an average follow-up period of 1 year (394 ±â€Š178 days), 92% of patients experienced no major shunt-related or scalp-related complications. There were 2 cases with a major complication requiring reoperation: 1 shunt tubing extrusion and 1 case of meningitis. The most frequent postsurgical intervention seen in this study was related to adjustment of drainage: a non-invasively performed valve reprogramming after initial shunt placement when proper flow rate is being established. Of the 8 cases of drainage adjustment, all but 1 (88%) were receiving a VPS for the first time, with the exception undergoing a fourth shunt revision. All instances of improper flow were treated non-surgically and remediated effectively via shunt reprogramming in clinic. Removal of the VACI was not indicated in any treatment course. In this way, all complications as they relate to the shunt valve were minor and required nonsurgical intervention, and no complications reported were directly or indirectly caused by using the VACI. CONCLUSION: Preliminary findings from this multicenter trial suggest promising outcomes with a low complication rate for patients with hydrocephalus undergoing VACI placement during VPS. Ongoing research will continue to provide a more robust clinical picture of VACI in hydrocephalus management as more data becomes available.

Dural Reconstruction With Autologous Rectus Fascia: A New Technique for Addressing Large-Sized Defects During Cranioplasty.

INTRODUCTION: Patients requiring cranioplasty reconstruction with customized cranial implants may unexpectedly present with cerebrospinal fluid (CSF) leaks and durotomies following previous neurosurgical procedures. As such, multiple factors influence the type of dural reconstruction chosen at this time, which are essential for achieving long-term success. Overall, the most common material used for duraplasty is currently an "off-the-shelf" xenograft construct. However, some believe that they are not suitable for large-sized defects and accompany a higher incident of complications. Therefore, based on our success and experience with scalp augmentation using rectus fascia grafts, the authors herein present our preliminary experience with duraplasty using autologous rectus fascia grafts (ARFGs). METHODS: A retrospective review of our database, consisting of 437 cranial reconstructions from 2012 to 2017, was performed under institutional review board approval. Selection criteria included all adult patients (n = 6) requiring dural reconstruction (duraplasty) with ARF grafting for an active CFS leak with concomitant skull defect. Cadaver study and patient illustrations are also presented to demonstrate clinical applicability. All outcomes, including complications, were reviewed and are presented here. RESULTS: A total of 6 patients underwent autologous duraplasty with either unilateral or bilateral ARFGs. All patients (6/6) of large-sized (>3 cm) defect repair with ARFGs were indicated for repair of secondary CSF leaks following previous craniotomy by neurosurgery. To date, none have demonstrated recurrent leaking and/or dura-related complications. At this time, all 6 patients were reconstructed using customized cranial implants with a mean follow-up of 10 months. CONCLUSION: Based on our preliminary experience presented here, the use of rectus fascia grafts for autologous dural reconstruction appears to be both safe and reliable. This new technique adds another tool to the neurosurgical armamentarium by reducing the additional risk of "off-the-shelf" dural substitutes.

Adult Cranioplasty.

OBJECTIVES: After reading this article, the participant should be able to: Understand the etiology of cranial defects. Understand the anatomy of the cranium. Understand the importance of the preoperative workup in the cranial reconstruction decision-making process. Describe the options available for calvarial reconstruction including autologous and alloplastic materials. Describe the basic differences between available alloplastic materials. Understand the intraoperative and postoperative complications that may arise during cranioplasty. SUMMARY: Cranial defects can arise from a variety of causes, yielding a diverse group of patients who require cranioplasty. The goals of calvarial reconstruction are to protect the underlying brain, to restore the aesthetic contour of the calvarium, and/or to treat postcraniectomy cerebrospinal fluid circulation abnormalities that may be symptomatic. Options for calvarial reconstruction include the autogenous bone flap that was removed for access, autologous bone grafting, and a variety of alloplastic materials such as titanium, hydroxyapatite, polymethylmethacrylate, polyether ether ketone, and high-density porous polyethylene. A detailed preoperative workup and discussion with the patient is important to choosing the appropriate reconstructive path.

Full-Thickness Skin Grafting for Local Defect Coverage Following Scalp Adjacent Tissue Transfer in the Setting of Cranioplasty.

INTRODUCTION: Numerous techniques have been described to overcome scalp deficiency and high-tension closure at time of cranioplasty. However, there is an existing controversy, over when and if a free flap is needed during complex skull reconstruction (ie, cranioplasty). As such the authors present here our experience using full-thickness skin grafts (FTSGs) to cover local defects following scalp adjacent tissue transfer in the setting of cranioplasty. METHODS: By way of an institutional review board-approved database, the authors identified patients treated over a 3-year period spanning January 2015 to December 2017, who underwent scalp reconstruction using the technique presented here. Patient demographics, clinical characteristics, technical details, outcomes, and long-term follow up were statistically analyzed for the purpose of this study. RESULTS: Thirty-three patients, who underwent combined cranioplasty and scalp reconstruction using an FTSG for local donor site coverage, were identified. Twenty-five (75%) patients were considered to have "high complexity" scalp defects prior to reconstruction. Of them, 12 patients (36%) were large-sized and 20 (60%) medium-sized; 21 (64%) grafts were inset over vascularized muscle or pericranium while the remaining grafts were placed over bare calvarial bone. In total, the authors found 94% (31/33) success for all FTSGs in this cohort. Two of the skin grafts failed due to unsuccessful take. Owing to the high rate of success in this series, none of the patient's risk factors were found to correlate with graft failure. In addition, the success rate did not differ whether the graft was placed over bone verses over vascularized muscle/pericranium. CONCLUSION: In contrary to previous studies that have reported inconsistent success with full-thickness skin grafting in this setting, the authors present a simple technique with consistent results-as compared to other more complex reconstructive methods-even in the setting of highly complex scalp reconstruction and simultaneous cranioplasty.

Sonolucent Cranial Implants: Cadaveric Study and Clinical Findings Supporting Diagnostic and Therapeutic Transcranioplasty Ultrasound.

BACKGROUND: Previously, sonographic evaluation of the intracranial contents was limited to intraoperative use following bone flap removal, with placement of the probe directly on the cortical surface or through a transsulcal tubular retractor. Cranioplasty with sonolucent implants may represent a postoperative window into the brain by allowing ultrasound to serve as a novel bedside imaging modality. The potential sonolucency of various commonly used cranial implant types was examined in this study. METHODS: A 3-phase study was comprised of cadaveric evaluation of transcranioplasty ultrasound (TCU) with cranioplasty implants of varying materials, intraoperative TCU during right-sided cranioplasty with clear implant made of poly-methyl-methacrylate (PMMA), and bedside TCU on postoperative day 5 after cranioplasty. RESULTS: The TCU through clear PMMA, polyether-ether-ketone, and opaque PMMA cranial implants revealed implant sonoluceny, in contrast to autologous bone and porous-polyethylene. Intraoperative ultrasound via the clear PMMA implant in a single patient revealed recognizable ventricular anatomy. Furthermore, postoperative bedside ultrasound in the same patient revealed comparable ventricular anatomy and a small epidural fluid collection corresponding to that visualized on an axial computed tomography scan. CONCLUSION: Sonolucent cranial implants, such as those made of clear PMMA, hold great promise for enhanced diagnostic and therapeutic applications previously limited by cranial bone. Furthermore, as functional cranial implants are manufactured with implantable devices housed within clear PMMA, the possibility of utilizing ultrasound for real-time surveillance of intracranial pathology becomes much more feasible.

Transcranioplasty Ultrasound Through a Sonolucent Cranial Implant Made of Polymethyl Methacrylate: Phantom Study Comparing Ultrasound, Computed Tomography, and Magnetic Resonance Imaging.

BACKGROUND: Current methods of transcranial diagnostic ultrasound imaging are limited by the skull's acoustic properties. Craniotomy, craniectomy, and cranioplasty procedures present opportunities to circumvent these limitations by substituting autologous bone with synthetic cranial implants composed of sonolucent biomaterials. OBJECTIVE: This study examined the potential to image the brain using transcranioplasty ultrasound (TCU) through a sonolucent cranial implant. MATERIALS AND METHODS: A validated adult brain phantom was imaged using computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound without an implant. Next, for experimental comparison, TCU was performed through a sonolucent implant composed of clear polymethyl methacrylate. RESULTS: All imaging modalities successfully revealed elements of the brain phantom, including the bilateral ventricular system, the falx cerebri, and a deep hyperdense mass representing a brain tumor or hematoma. In addition, ultrasound images were captured which closely resembled axial images obtained with both CT and MRI. CONCLUSION: The results obtained in this first-ever, preclinical, phantom study suggest TCU is now a viable immediate and long-term diagnostic imaging modality deserving of further clinical investigation.

Introducing the Rectus Fascia Scalp Augmentation Technique: A New Method for Improving Scalp Durability in Cranioplasty Reconstruction.

OBJECTIVE: Patients with cranioplasty in need of skull reconstruction are at increased risk of complications when presenting with abnormally thin scalps. As such, the authors sought to develop and investigate a new technique for scalp augmentation using autologous rectus fascia grafts (ARFGs) for prevention of implant extrusion and long-term scalp durability. METHODS: A retrospective review of our database, consisting of 450 consecutive cranial reconstructions from 2012 to 2017, was performed under institutional review board approval. Selection criteria included all adult patients requiring implant-based cranioplasty reconstruction and concomitant scalp augmentation using ARFGs. All long-term outcomes were reviewed for scalp-related complications and are presented here. RESULTS: In total, 12 consecutive patients receiving ARFGs were identified. Average follow-up was 10 months (range = 2-17 months). Average graft size and dimension was 82 cm (range = 12-360 cm). All patients (n = 12) underwent concomitant cranioplasty reconstruction and had a history of at least 5 or greater previous neurocranial operations. Six patients had radiation therapy prior to cranioplasty. Two major complications (2/12, 17%) were identified related to deep, recurrent intracranial infections. More importantly, none of the patients (n = 12) in this study cohort developed scalp breakdown and/or implant extrusion in the areas of rectus fascia scalp augmentation. CONCLUSION: The use of ARFGs for underlay scalp augmentation appears to be both safe and reliable based on our preliminary experience. This new approach is extremely valuable when performing large-size cranioplasty reconstruction in patients with abnormally thin scalps, an extensive neurosurgical history, and/or suboptimal tissue quality. Furthermore, this method has been successful in avoiding free tissue transfer and/or staged tissue expansion as first-line surgery in our complicated cranioplasty population.

Comparative Cost Analysis of Single and Mutli-Stage Temporal Deformity Correction Following Neurosurgical Procedures.

PURPOSE: Temporal hollowing deformity (THD) is a visible concavity/convexity in the temporal fossa; a complication often seen following neurosurgical/craniofacial procedures. Although numerous techniques have been described, no study to date has shown the healthcare costs associated with temporal hollowing correction surgery. Thus, the purpose here is to compare and contrast the direct costs related to temporal cranioplasty using various methods including: liquid poly-methyl-methacrylate (PMMA) implants with screw fixation, prebent, modified titanium mesh implants, and customized cranial implants (CCIs) with dual-purpose design. Understanding the financial implications related to this frequently encountered complication will help to motivate surgeons/healthcare facilities to better prevent and manage THD. METHODS: This is a single-surgeon, single-institution retrospective review of 23 THD patients randomly selected from between 2008 and 2015. Cost analysis variables include length of hospital stay, facility/professional fees, implant material fees, payer information, reimbursement rate, and net revenue. RESULTS: Of the 23 patients, ages ranged from 23 to 68 years with a mean of 48.3 years (SD 11.6). Within this cohort, 39.1% received dual-purpose PMMA CCIs (CCI PLUS), 17.4% received modified titanium mesh implants, and 43.5% received hand-molded, liquid PMMA implants with screw fixation. Total facility and/or professional charges ranged from $1978.00 to $126478.00. Average total facility charges per patient with dual-purpose CCIs were $34775.89 (SD ±â€Š$22205.09) versus $35826.00 (SD ±â€Š$23509.93) for modified titanium mesh implants and $46547.90 (SD ±â€Š81061.70) for liquid PMMA implants with screws. Mean length of inpatient stay was 5.7 days (SD = 8.1), and did not differ between implant types (P = 0.387). CONCLUSION: Temporal hollowing deformity is an expensive complication post-neurosurgery, and in the most severe form, requires a revision surgery for definitive correction. Therefore, surgeons should take further initiatives to employ reconstructive methods capable of minimizing risk for costly revision surgery, reducing morbidity related to visible deformity and accompanying social stigmata, and improving overall patient satisfaction.

Improving Postoperative Nasal Airway Patency in Le Fort-Based, Maxillofacial Trauma Patients Via a Modified Nasal Packing Technique.

INTRODUCTION: Combined mid-face and nasal apparatus trauma injuries pose a significant challenge to airway patency (AW), in the immediate postoperative setting following fracture reduction. As such, the authors describe a modified technique with the goal of maintaining a patent nasal AW, while at the same time, minimizing nasopharyngeal bleeding and nasal AW edema-which can complicate patients requiring intermaxillary fixation (IMF) in the setting of pan-facial trauma. METHODS: A modified technique was devised to assist the reconstruction surgeon in avoiding the risks associated with tracheostomy placement. In an effort to avoid surgical AW complications and improve nasal AW patency in the setting of concurrent IMF and nasal trauma, the authors developed a 2-stage technique drawing upon knowledge from the literature and the authors' own experiences. TECHNIQUE: Following safe extubation, the authors insert open lumen nasal splints in both the nostrils, and suture them together to the nasal septum. If additional inner nasal support is required, polyvinyl alcohol nonabsorbable nasal packing dressing is covered with antibiotic ointment, and then placed within the nasal cavity lateral to the open lumen splints-as a way to further bolster the internal valve and mid-vault anatomy. DISCUSSION: Given the fact that traditional nasal packing with merocele/gauze dressing in concomitant to IMF reduced patients ability to ventilate, the authors felt that a modified technique should be applied. The authors' preferred materials in such patients are open lumen splint, which provides nasal AW patency along with some septum support accompanied by merocele dressing. The authors feel that by applying this technique they achieve dual objectives by supporting the traumatized nose and maintaining nasal AW patency.