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This retrospective analysis of the Extracorporeal Life Support Organization (ELSO) registry evaluates the outcomes and identifies risk factors associated with conversion from initial venovenous extracorporeal membrane oxygenation (ECMO) support to venoarterial or hybrid ECMO in patients with coronavirus disease 2019 (COVID-19). We collected deidentified data on all adult patients (≥18 years old) diagnosed with COVID who received venovenous extracorporeal membrane oxygenation between March 2020 and November 2022. Patients initially placed on an ECMO configuration other than venovenous (VV) ECMO were excluded from the analysis. Our analysis included data from 12,850 patients, of which 393 (3.1%) transitioned from VV ECMO to an alternative mode. The primary outcome measure was in-hospital mortality, and the conversion group exhibited a higher in-hospital mortality rate. We also examined baseline variables, including demographic information, biochemical labs, and inotrope requirements. Univariate analysis revealed that pre-ECMO arrest, the need for renal replacement therapy, and the use of inotropic agents, particularly milrinone, were strongly associated with the risk of conversion. Notably, even after implementing a 3:1 propensity score matching, the impact of conversion on both mortality and complications remained substantial. Our study underscores an elevated risk of mortality for COVID-19 patients initially treated with VV ECMO who subsequently require conversion to VA-ECMO or hybrid ECMO., Competing Interests: Disclosure: The authors have no conflicts of interest to report., (Copyright © ASAIO 2024.)

Purpose of Review: Early revascularization, invasive hemodynamic profiling, and initiation of temporary mechanical circulatory support (MCS) have all become routine components of cardiogenic shock (CS) management. Despite this evolution in clinical practice, patient selection and timing of treatment initiation remain a significant barrier to achieving sustained improvement in CS outcomes. Recent efforts to standardize CS management, through the development of treatment algorithms, have relied heavily on surrogate endpoints to drive therapeutic decisions. The present review aims to provide an overview of the basis of evidence for those surrogate endpoints commonly employed in clinical trials and CS management algorithms., Recent Findings: Recent publications from both observational and randomized cohorts have demonstrated the utility of surrogate endpoints in risk stratifying patients with CS. In particular, invasive hemodynamics using pulmonary artery catheters to guide initiation and weaning of MCS, biochemical markers that portend imminent end-organ failure, and clinical risk scores that combine multiple hemodynamic and laboratory parameters have demonstrated an ability to prognosticate outcomes in patients with CS., Summary: Although further validation is necessary, multiple clinical, hemodynamic, and biochemical markers have demonstrated utility as surrogate endpoints in CS, and will undoubtedly assist physicians in clinical decision-making., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Identifying a structural brain lesion on MRI has important implications in epilepsy and is the most important factor that correlates with seizure freedom after surgery in patients with drug-resistant focal onset epilepsy. However, at conventional magnetic field strengths (1.5 and 3T), only approximately 60%-85% of MRI examinations reveal such lesions. Over the last decade, studies have demonstrated the added value of 7T MRI in patients with and without known epileptogenic lesions from 1.5 and/or 3T. However, translation of 7T MRI to clinical practice is still challenging, particularly in centers new to 7T, and there is a need for practical recommendations on targeted use of 7T MRI in the clinical management of patients with epilepsy. The 7T Epilepsy Task Force-an international group representing 21 7T MRI centers with experience from scanning over 2,000 patients with epilepsy-would hereby like to share its experience with the neurology community regarding the appropriate clinical indications, patient selection and preparation, acquisition protocols and setup, technical challenges, and radiologic guidelines for 7T MRI in patients with epilepsy. This article mainly addresses structural imaging; in addition, it presents multiple nonstructural MRI techniques that benefit from 7T and hold promise as future directions in epilepsy. Answering to the increased availability of 7T MRI as an approved tool for diagnostic purposes, this article aims to provide guidance on clinical 7T MRI epilepsy management by giving recommendations on referral, suitable 7T MRI protocols, and image interpretation., (© 2020 American Academy of Neurology.)

Background: Facial appearance transfer from donor to recipient in face transplantation is a concern. Previous studies of facial appearance transfer and facial appearance persistence (preservation of the recipient's facial likeness) in face transplants simulated using two-dimensional photographic manipulations found low facial appearance transfer (2.6 percent) and high facial appearance persistence (66 percent). Three-dimensional computer simulation of complex facial transplant patterns may improve the accuracy of facial appearance transfer and facial appearance persistence estimations., Methods: Three-dimensional virtual models of human faces were generated from deidentified computed tomographic angiographs and used as "donors" or "recipients" for virtual face transplantation. Surgical planning software was used to perform 73 virtual face transplantations by creating specific facial defects (mandibular, midface, or large) in the recipient models and restoring them with allografts extracted from the donor models. Twenty independent reviewers evaluated the resemblance of each resulting posttransplant model to the donor (facial appearance transfer) and recipient (facial appearance persistence). The results were analyzed using tests for equal results with one-sample and pairwise Rao-Scott Pearson chi-square testing, correcting for clustering and multiple testing., Results: Overall rates of facial appearance persistence and facial appearance transfer were high (69.2 percent) and low (32.4 percent), respectively. The mandibular pattern had the highest rates of facial appearance persistence and lowest rates of facial appearance transfer. Facial appearance persistence and transfer were similar across sexes., Conclusions: Facial appearance persistence is high and facial appearance transfer is low after virtual face transplantation. Appearance transfer and persistence after virtual face transplantation are more dependent on the anatomy than on the size of transplanted facial aesthetic units. This information may reassure recipients of partial face transplants and donor families.

Background: Fat grafting is a powerful tool for soft-tissue reconstruction; however, the science behind recipient bed preparation has not been thoroughly explored. External volume expansion using suction before fat grafting has been used clinically to improve reliability and consistency of graft survival. The authors developed a murine model to investigate the underlying mechanism of external volume expansion., Methods: The authors created an external volume expansion device using a soft-silicone dome connected to a vacuum source (25 mmHg) to treat the dorsum of mice, and the response was compared with treatment with an occlusive dressing. Treated areas were monitored with magnetic resonance imaging. Remodeling of microvasculature was studied with corrosion casting on day 7. Effects on tissue thickness, number of adipocytes, cell proliferation, and blood vessel density were analyzed at 28 days., Results: Macroscopic analysis showed tissue swelling at sites treated with the external volume expansion device by 21 days, without skin damage. On day 28, external volume expansion increased the thickness of the subcutaneous fat layer twofold, consistent with magnetic resonance imaging observations. The proliferation rate in the subcutaneous layer of expansion-treated areas increased twofold, with a net 2.2-fold increase in number of adipocytes in columns; remodeling of the vessels network occurred, with reorientation and increase of vessel diameters shown by corrosion casting and 1.9-fold augmentation of vessels density., Conclusions: External volume expansion applied to mouse integument induces highly proliferative and vascularized subcutaneous tissue. Recipient-site preparation using external volume expansion devices may be a promising tool to enhance cell and tissue engraftment.

Some patients with sagittal synostosis present with a fused metopic suture. We hypothesize that premature metopic suture fusion consistently and identifiably alters form associated with sagittal synostosis. We previously validated three-dimensional vector analysis as a tool for the study of cranial morphology and used it herein to distinguish between dysmorphologies of isolated sagittal synostosis (ISS) and combined sagittal-metopic synostosis (CSM). Preoperative computed tomographic scans for patients with ISS and CSM were compared with matched normative counterparts. Premature metopic suture fusion was defined by established radiographic criteria. Color-coded point clouds were created for each scan, with color gradient based on patient deviation from normal across the dysmorphic skull. Standard deviation data were evaluated in 7 cranial regions and compared between ISS and CSM. Mean ISS and CSM point clouds were evaluated. Using three-dimensional vector analysis, standard anthropometric data/indices were determined and compared between the 2 groups. Differences in ISS and CSM regional deviations and index measurements were not statistically significant. Mean ISS and CSM representations depicted similar overall morphology. Using accepted criteria for identification of metopic synostosis in CSM, only subtle differences appear between the 2 populations on average. Expected morphologic changes associated with metopic synostosis are present in only a small number of patients with CSM, arguing against our hypothesis, and calling into question the criteria used to identify premature metopic suture fusion. Normal metopic suture fusion occurs for a continuum of time. Our findings suggest that the normal continuum may begin earlier than the literature suggests. In the setting of sagittal synostosis, the influence of metopic suture fusion and treatment is best determined by individual morphologic analysis.

Because of the success of stereotactic radiosurgery (SRS) in the treatment of cerebral arteriovenous malformations (AVMs), SRS is being applied to the treatment of carotid-cavernous dural arteriovenous fistulas (CCDAVFs) when these lesions are not accessible endovascularly. We report a patient with a CCDAVF that could not be accessed endovascularly on 2 attempts, whose fistula was successfully closed with SRS, a less invasive modality than endovascular embolization. Further experience with SRS in this role will be necessary to determine its utility.

Background: Surgical correction of cranial abnormalities, including craniosynostosis, requires knowledge of normal skull shape to appreciate dysmorphic variations. However, the inability of current anthropometric techniques to adequately characterize three-dimensional cranial shape severely limits morphologic study. The authors previously introduced three-dimensional vector analysis, a quantitative method that maps cranial form from computed tomography data. In this article, the authors report its role in the development and validation of a normative database of pediatric cranial morphology and in clinical analysis of craniosynostosis., Methods: Normal pediatric craniofacial computed tomography data sets were acquired retrospectively from the Duke University Picture Archive and Communications System. Age increments ranging from 1 to 72 months were predetermined for scan acquisition. Three-dimensional vector analysis was performed on individual data sets, generating a set of point clouds. Averages and standard deviations for the age and gender bins of point clouds were used to create normative three-dimensional models. Anthropometric measurements from three-dimensional vector analysis models were compared with published matched data. Preoperative and postoperative morphologies of a sagittal synostosis case were analyzed using three-dimensional vector analysis and the normative database., Results: Three- and two-dimensional representations were created to define age-incremental normative models. Length and width dimensions agreed with previously published data. Detailed morphologic analysis is provided for a case of sagittal synostosis by applying age- and gender-matched data., Conclusions: Three-dimensional vector analysis provides accurate, comprehensive description of cranial morphology with quantitative graphic output. The method enables development of an extensive pediatric normative craniofacial database. Future application of these data will facilitate analysis of cranial anomalies and assist with clinical assessment.

Background: The physiologic effects of specific rhinoplasty maneuvers are incompletely understood, largely because of a limited ability to objectively examine such interventions. The purpose of this study was to develop and validate a cadaveric model for rhinoplasty testing., Methods: Ten cadaver heads were methodically prepared to simulate ventilatory conditions. Airway dimensions were measured with three-dimensional computed tomography and acoustic rhinometry. Airflow, pressure, and resistance were measured under conditions of both inhalation and exhalation. Resistance was determined using active anterior rhinomanometry and a continuously variable pressure gradient. Anatomic and physiologic properties were first compared against normative data. Measurements were then taken after application of an adhesive external midvault dilator (BreatheRight; GlaxoSmithKline)., Results: The average minimal cross-sectional areas by acoustic rhinometry and by computed tomography were 0.87 cm2 and 0.84 cm2 per nostril, respectively (n = 20). The average distance from the nostril to the internal nasal valve was 1.7 cm by acoustic rhinometry and 1.5 cm by computed tomography, consistent with published in vivo normative data at the internal nasal valve. The average resistance with simulated exhalation closely approximated known normative values. With the application of the adhesive nasal dilator, the average area (acoustic rhinometry) increased by 50 percent at the internal nasal valve. During inhalation, the resistance decreased by 21 percent following application of the adhesive dilator., Conclusions: The model provides an accurate representation of nasal anatomy and physiology suitable for objective analysis of rhinoplasty maneuvers. The objective modalities used herein may be applied to rhinoplasty study using this model with accuracy and reproducibility. The external dilator increased area at the internal valve (minimal cross-sectional area) and decreased resistance.

The safety of medical radiation, particularly computed tomography, has recently received much attention in both the medical literature and the popular press. As knowledge regarding side effects of radiation exposure has increased, so have attempts to limit doses to patients through more selective use of scans and transitions to lower-dose protocols to conform to the As Low As Reasonably Achievable (ALARA) principle. This trend has been apparent across many fields within medicine, including craniofacial surgery. Craniofacial surgeons should be familiar with these issues to participate in the determination of practice standards and to address patient concerns. A number of authors have questioned the value and necessity of obtaining computed tomography scans for the management of single-suture craniosynostosis in light of known radiation risks. Although unnecessary exposure to radiation from computed tomography scans should be avoided, imaging provides useful--often vital--information to the treatment of craniosynostosis. Use of low-dose protocols, which have been shown to provide images of satisfactory quality for the evaluation of both suture patency and associated intracranial abnormalities, may be a favorable alternative. The authors discuss the issue of medical radiation and its risks. In the context of risks and benefits, the authors reviewed the current practice of imaging in craniofacial surgery with the intent to encourage dialogue between surgeons and radiologists to develop thoughtful practice standards.

Background: Orbital floor injuries can occur in isolation or in association with zygomaticomaxillary complex fractures. Volumetric computed tomographic measurements of affected orbits are investigated for utility in guiding management in these two groups., Methods: The medical records of all patients with craniomaxillofacial injuries (2003 to 2005) were reviewed. Of 522 total patients, 45 patients had isolated orbital floor fractures, 13 of whom underwent repair (29 percent), and 64 had zygomaticomaxillary complex fractures, 36 of whom underwent reconstruction (56 percent) and 10 of whom underwent orbital floor repair (16 percent). Radiographic criteria for floor exploration included 50 percent area fracture in isolated injuries and 10-mm estimated zygomaticomaxillary complex compression in zygomaticomaxillary complex-associated floor injuries. Volume measurements of the affected orbits were obtained and compared with the uninjured contralateral orbit., Results: Before treatment in the operative zygomaticomaxillary complex group, there was an average decrease in orbital volume of 18.3 percent. In the isolated orbital floor group, there was an average increase in orbital volume of 28.3 percent., Conclusions: Zygomaticomaxillary complex-associated orbital floor injuries can be compressive injuries associated with loss of volume, whereas isolated injuries generally result in volume expansion. Radiographic criteria are often considered in the decision to proceed with orbital floor exploration to avoid late enophthalmos. The literature suggests that a 20 percent change in orbital volume results in perceptible deformity. Therefore, a radiographic criterion of 50 percent floor area (28 percent volume increase) in isolated injuries may be too stringent; an estimated 10 mm of compression (18.3 percent volume change) is a reasonable operative criterion for floor exploration in zygomaticomaxillary complex-associated injuries.

Background: Patients with panfacial fractures comprise a small portion of the overall facial fracture patient population. Because of the forces necessary to cause panfacial injury, these patients often have other concomitant injuries. The timing of operative facial fracture management remains controversial., Methods: A 3-year review of all patients with facial fractures was conducted at Duke University Medical Center (2003-2005, 437 total patients). All patients with panfacial fractures, defined as fractures involving at least three of the four facial segments (frontal, upper midface, lower midface, and mandible), were analyzed., Results: Panfacial fractures were present in 38 patients (9% of overall facial fracture population). Twenty (53%) of these patients suffered concomitant injuries. The most common mechanism of trauma was motor vehicle collision, and the most common category of concomitant injury was intracranial injury or hemorrhage. Other commonly occurring categories of injury included abdominal organ injury, pneumothorax, pulmonary contusion, spine fracture, rib or sternum fracture, extremity fracture, and pelvic fractures. There was no significant difference in day of operation for the management of facial fractures between those with isolated facial injuries and those with other concomitant injuries (hospital day 2.1 vs. hospital day 2.9, not significant)., Conclusions: Concomitant injuries to all parts of the body are found in patients with panfacial trauma. In our experience, these injuries do not significantly delay or have an adverse effect on the treatment of facial fractures. A treatment strategy for consistent timely management of facial fractures is described.

In a patient with a known difficult airway, history and examination may be of limited use in formulating a management plan for subsequent tracheal intubation. Further detailed and descriptive review of the airway is necessary. Virtual imaging is a recent advance in radiology that offers noninvasive airway assessment. It creates a movie clip image of the upper airway akin to the view obtained through a fiberscope. We present a patient with Goldenhar syndrome in whom virtual imaging was used to identify the cause of a previous failed tracheal intubation.

Background: Face transplantation may become a viable alternative in the treatment of patients with severe acquired facial deformity. In this study, the authors investigate morphological compatibility between donor and recipient by assessing chimeric outcomes in a human cadaver model., Methods: Four faces were harvested from fresh human cadaver specimens in a surgical plane deep to the galea, to the superficial musculoaponeurotic system, and to the platysma. The faces were subsequently exchanged among the four donor crania, simulating full-face transplantations. Eight cranium-face chimera complexes were created and analyzed with standardized photography and with volumetric computed tomographic radiography., Results: Four morphological parameters to consider in determining donor/recipient compatibility were defined: (1) skin color and texture, (2) head size, (3) soft-tissue features, and (4) gender., Conclusion: Careful selection of face donors based on compatibility criteria will aid in ensuring that the posttransplant outcome is morphologically similar to the recipient's native face.

Consensus remains lacking regarding the optimal surgical treatment modality for sagittal synostosis. There is, however, wide agreement that objective analytical methods are required to demonstrate the characteristic morphology of the condition and to substantiate the benefits of specified surgical techniques. Simple calculated anthropomorphic indices, such as the cranial index, are commonly used but fail to provide satisfactory representation of morphology, which is far more complex than can be represented by its simple length-width ratio. Techniques to provide more comprehensive, yet practical, assessment of morphology are needed for analytic purposes. Herein, we introduce vector analysis as an objective, computed tomography (CT)-based morphometric technique for assessment of cranial morphology; this work represents the first application of the technique mid-sagittal vector analysis (MSVA). MSVA is a single plane application that was devised to address dysmorphology in sagittal synostosis. It was our hypothesis that MSVA would quantitatively and qualitatively depict preoperative morphology and postoperative correction in specific regions. Sixteen patients undergoing cranial reshaping surgery for sagittal synostosis were included in the study. All patients underwent routine preoperative and 1 year postoperative CT scans, from which the MSVA was derived. MSVA is a radial vector analysis in which distances to the cranial surface are measured from a single reference point origin in the sagittal plane. Preoperative morphology, characterized by respective vectors, was analyzed in three regions: the frontal, vertex, and occipital regions. Comparison with postoperative paired data was conducted for each patient. The analysis of postoperative change demonstrated (1) decrease in prominence in the frontal and occipital regions, (2) increase in height and forward translation of the vertex, and (3) ability to distinguish and qualify frontal versus occipital bossing and correction thereof. We conclude that the longitudinal differences associated with scaphocephaly are well characterized and differentiated by MSVA. Quantitative and qualitative assessment identifies three relevant regions affected by the condition and its treatment: the frontal, vertex, and occipital regions. The transverse dimension is not addressed in this single plane analysis; a more comprehensive application will require additional planes of analysis and the development of a normative database.