Design and Validation of a 3D Printed Cranio-Facial Simulator: A Novel Tool for Surgical Education.

OBJECTIVE: To assess the ability of current 3D printing technology to generate a craniofacial bony and soft tissue anatomical model for use in simulating the performance of a fronto-orbital advancement (FOA) osteotomy and then to further assess the value of the model as an educational tool. DESIGN: Anatomic models were designed with a process of serial anatomic segmentation/design, 3D printing, dissection, and device refinement. A validation study was conducted with 5 junior and 5 senior plastic surgery residents. The validation study incorporated a multiple-choice Knowledge Assessment test (KA), an Objective Structured Assessment of Technical skills (OSATs), a Global Rating Scale (GRS) and a Michigan Standard Simulation Experience Scale (MiSSES). We compared the scores of both the junior and senior residents and compared junior resident scores, before and after viewing a lecture/demonstration. RESULTS: MiSSES showed high face validity with a score of 85.1/90, signifying high satisfaction with the simulator learning experience. Simulation and the lecture/demonstration improved the junior resident average KA score from 5.6/10 to 9.6/10 (P = .02), OSATs score from 32.4/66 to 64.4/66 (P < .001) and GRS score from 13.9/35 to 27.5/35 (P < .001). The senior residents OSATs score of 56.3/66 was higher than the pre-lecture juniors (32.4/66) (P < .001), but lower than the post-lecture juniors (64.4/66) (P < .001). CONCLUSION: We have successfully fabricated a 3D printed craniofacial simulator capable of being used as an educational tool alongside traditional surgical training. Next steps would be improving soft tissue realism, inclusion of patient and disease specific anatomy and creation of models for other surgical specialties.

Three-dimensional cardiac print assisted percutaneous closure of left ventricular pseudoaneurysm in patient with Behçet's disease.

Spontaneous left ventricular pseudoaneurysms are very rare and can have catastrophic consequences if unrecognized. A case of combined spontaneous left ventricular aneurysm and pseudoaneurysm in Behcet's disease (BD) has been reported. The case emphasizes advanced techniques for percutaneous closure of the defects with the use of an ex-vivo three-dimensional cardiac printed model as a tool to facilitate the procedure.

3-Dimensional Printed Alternative to the Standard Synthetic Flocked Nasopharyngeal Swabs Used for Coronavirus Disease 2019 Testing.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), can be detected in respiratory samples by real-time reverse transcriptase polymerase chain reaction (RT-PCR) or other molecular methods. Accessibility of diagnostic testing for COVID-19 has been limited by intermittent shortages of supplies required for testing, including flocked nasopharyngeal (FLNP) swabs. METHODS: We developed a 3-dimensional printed nasopharyngeal (3DP) swab as a replacement of the FLNP swab. The performance of 3DP and FLNP swabs were compared in a clinical trial of symptomatic patients at 3 clinical sites (n = 291) using 3 SARS-CoV-2 emergency use authorization tests: a modified version of the Centers for Disease Control and Prevention (CDC) RT-PCR Diagnostic Panel and 2 commercial automated formats, Roche Cobas and NeuMoDx. RESULTS: The cycle threshold-C(t)-values from the gene targets and the RNase P gene control in the CDC assay showed no significant differences between swabs for both gene targets (P = .152 and P = .092), with the RNase P target performing significantly better in the 3DP swabs (P < .001). The C(t) values showed no significant differences between swabs for both viral gene targets in the Roche cobas assay (P = .05 and P = .05) as well as the NeuMoDx assay (P = .401 and P = .484). The overall clinical correlation of COVID-19 diagnosis between all methods was 95.88% (Kappa 0.901). CONCLUSIONS: The 3DP swabs were equivalent to standard FLNP in 3 testing platforms for SARS-CoV-2. Given the need for widespread testing, 3DP swabs printed onsite are an alternate to FLNP that can rapidly scale in response to acute needs when supply chain disruptions affect availability of collection kits.

A review of visualization techniques of post-mortem computed tomography data for forensic death investigations.

Postmortem computed tomography (PMCT) is a standard image modality used in forensic death investigations. Case- and audience-specific visualizations are vital for identifying relevant findings and communicating them appropriately. Different data types and visualization methods exist in 2D and 3D, and all of these types have specific applications. 2D visualizations are more suited for the radiological assessment of PMCT data because they allow the depiction of subtle details. 3D visualizations are better suited for creating visualizations for medical laypersons, such as state attorneys, because they maintain the anatomical context. Visualizations can be refined by using additional techniques, such as annotation or layering. Specialized methods such as 3D printing and virtual and augmented reality often require data conversion. The resulting data can also be used to combine PMCT data with other 3D data such as crime scene laser scans to create crime scene reconstructions. Knowledge of these techniques is essential for the successful handling of PMCT data in a forensic setting. In this review, we present an overview of current visualization techniques for PMCT.

Aging of the Adult Bony Orbit.

BACKGROUND: Accurate quantitative data of the adult bony orbital volume and dimension are needed for treatment optimization. In the present study, the authors aim to evaluate adult orbital volume and corresponding linear dimensions according to age, volume, and individual symmetry. METHODS: Seventy computerized tomography facial scans of adults were randomly chosen from an institutional database and 3-dimensionally reconstructed. Studies were excluded for orbital pathology or incomplete radiographic data. Anatomic landmarks were marked. Interval linear distances and orbital volumes were calculated. Data were analyzed using paired T-tests, independent T-tests, linear regression analysis, and 1-way analysis of variance. RESULTS: A total of 140 orbits from 70 patients were analyzed (female = 35, male = 35), ranging from 20 to 88 years of age. Orbital volume was similar between an individual's left and right side; however, a difference was observed in vertical orbital height, orbital width, inferior orbital rim position, orbital roof length, orbital width, and medial orbital wall length (0.45, 0.64, 0.4, 0.77, 0.97, and 5.1 mm, respectively; P < 0.05). In comparison to females, males averaged larger orbital volume by 3.07 cm (29.58 cm versus 26.51 cm, P = 0.0002), medial wall length by 2.66 mm (P < 0.05), and orbital width by 2.66 mm (P < 0.05). Orbital volume did not correlate with patient age, while lateral wall length was correlative. CONCLUSION: This accurate normative data of the adult bony orbit impacts key aspects of patient diagnosis and treatment and also suggest clinical signs of periorbital aging are not due to bony orbital changes.

Three-Dimensional Morphological Analysis of Sex, Age, and Symmetry of Proximal Femurs from Computed Tomography: Application to Total Hip Arthroplasty.

The success of a total hip arthroplasty is directly related to the ability of the implant to match original femoral morphology. Given this critical relationship, we characterized normal proximal femoral morphology as it relates to sex, age, and symmetry. Sixty abdominopelvic computed tomography (CT) scans (30 male and 30 female, ages 20-85 years old) from patients without any osseous pathology or implants were utilized. Three-dimensional models were constructed from the CT scans using Mimics v19 (Materialize). Thirteen landmarks were placed on each femur model and yielded eight morphological measurements for each femur. Medullary cavity measurements were taken superior to, at the center of, and inferior to the lesser trochanter. Morphological measurements were analyzed by sex, age group, and left versus right. A significant difference was identified between males and females for femoral head height, inferior neck length, minimum neck diameter, neck shaft angle, mediolateral medullary cavity measurement superior to the lesser trochanter and the anteroposterior at the lesser trochanter (P < 0.05). Age was found to correlate with medullary cavity measurements. As previously identified in the literature, differences with respect to the right and left femur were not of practical significance. The results show that sex is critical in determining prosthesis fit with the examined morphological measurements of the proximal femur while age is more important with respect to the medullary cavity. It is also evident that the current practice of using one femur to approximate the opposite is a viable clinical assumption. Clin. Anat., 33:731-738, 2020. © 2019 Wiley Periodicals, Inc.

Potential use of deep learning techniques for postmortem imaging.

The use of postmortem computed tomography in forensic medicine, in addition to conventional autopsy, is now a standard procedure in several countries. However, the large number of cases, the large amount of data, and the lack of postmortem radiology experts have pushed researchers to develop solutions that are able to automate diagnosis by applying deep learning techniques to postmortem computed tomography images. While deep learning techniques require a good understanding of image analysis and mathematical optimization, the goal of this review was to provide to the community of postmortem radiology experts the key concepts needed to assess the potential of such techniques and how they could impact their work.

Angioedema and Dual Nurse Flight Crew Cricothyrotomy After Envenomation by a Severed Rattlesnake Head.

Crotalid envenomation may result in airway compromise from angioedema, anaphylaxis, or an anaphylactoid reaction. A 57-year-old man was transported by helicopter to the emergency department (ED) after a bite to his hand from a severed rattlesnake head. He rapidly developed facial and oropharyngeal edema that did not respond to standard treatment. After 2 unsuccessful attempts at intubation, the dual flight nurse team performed a cricothyrotomy. They notified the ED team en route, and antivenom was prepared before arrival. Angioedema was suspected because there was no concomitant urticaria, bronchoconstriction, or persistent hypotension. Edema and ecchymosis of the affected extremity were mild. Severe coagulopathy ensued, which was treated with bolus doses of antivenom and continuous infusion. This case report is significant for several reasons. It is the first detailing a prehospital cricothyrotomy performed by flight crew nurses for life-threatening airway edema caused by snakebite envenomation. In-flight notification enabled the ED staff to prepare and administer antivenom immediately after arrival. Despite the use of antivenom in bolus dosing, crotalid envenomation may be complicated by persistent or recurring coagulopathy, and continuous antivenom infusion may be useful. Finally, it highlights the danger of snakebite envenomation even after the death and decapitation of a snake.

3D analysis of computed tomography (CT)-derived lumbar spine models for the estimation of sex.

When skeletal remains are found scattered or in fragmentary conditions, the establishment of a biological profile of unknown individuals can be proven difficult. Consequently, multiple methods to ascertain the sex of the individual must be developed. The purpose of this study was to demonstrate that computed tomographic (CT)-derived 3D models of lumbar vertebrae could capture the unique morphologies of all five lumbar vertebrae to create equations for sex identification. The models were selected from a modern population consisting of 154 males and females that measured 30 standard linear measurements, the vertebral body wedging angle, and five aspect ratios. These measurements were then used to develop discriminant function equations for sex identification. Each lumbar level was analyzed individually as well as part of the entire lumbar spinal column. The results of this study showed that L1-L5 vertebrae can be used in sex determination with an 81.2-85.1% accuracy. When all five vertebrae are used in conjunction, the accuracy is 92.2%. The accuracy of the sex estimation found in this study for all lumbar vertebrae reinforces the distinct dimorphism between sexes while also providing forensic practitioners with more options or tools for their analyses.

Adding Depth to Cephalometric Analysis: Comparing Two- and Three-Dimensional Angular Cephalometric Measurements.

INTRODUCTION: Lateral cephalometric radiographs (LCR) have been the standard tool used for cephalometric analysis in craniofacial surgery. Over the past decade, a three-dimensional (3D) revolution in cephalometric analysis and surgical planning has been underway. To date, research has not validated whether cephalometric measurements taken from two-dimensional (2D) and 3D data sources are equivalent and interchangeable. The authors sought to compare angular cephalometric measurements taken with 2D and 3D modalities. METHODS: Sixty-two head CT scans (36 females, 26 males) with an average age of 63 ±â€Š20 years were studied. Twelve cephalometric angular measurements were taken from 3D reconstructed skulls using the software package Mimics 19.0 (Materialize; Leuven, Belgium). These same facial angles were measured from 2D lateral cephalograms reconstructed from the original CT scans using Dolphin 11.9. Measurements taken with both techniques were compared for agreement using a paired t test. Intra-class correlation coefficient assessment was used to determine inter-rater reliability. Statistical significance was set at P < 0.05. RESULTS: Five of the 12 angular measurements (SNA, SNB, MP-FH, U1-SN, and U1-L1) demonstrated statistically significant differences (P < 0.05) between the 2D and 3D analyses. All of these differences were less than the standard deviations for the respective measure. CONCLUSION: The differences between angular cephalometric values obtained from 2D LCRs and 3D CT reconstructions are small. This supports the practices of using 2D and 3D cephalometric data interchangeably in most applications. Clinicians must be selective in which measures they employ to maximize accuracy and care must be taken when measuring dental inclination with lateral cephalograms.

Monitoring the corrected QT in the acute care setting: A comparison of the 12­lead ECG and bedside monitor.

INTRODUCTION: Prolongation of the QT interval is a well-recognized complication associated with many commonly used medications. Emergency Department monitoring of the corrected QT (QTc) both before and after medication administration is typically performed using the 12­lead electrocardiogram (ECG). The purpose of this study is to compare the QTc reported on the 12­lead ECG to that reported by single brand of bedside monitor. METHODS: A convenience sample of emergency department patients over the age of 18 undergoing bedside monitoring and who had an ECG ordered by their treating physician were enrolled. These patients underwent simultaneous ECG and monitor QTc calculation. The primary outcome of interest was the correlation between the monitor and ECG QTc. Secondary outcomes included ability of each method to identify patients with a QTc >500ms and the ability of each method to identify patients with a QTc <450ms. RESULTS: A total of 125 patients had simultaneous ECG and monitor QTc measurements recorded. There was moderate correlation between the monitor and ECG QTc (Pearson's correlation coefficient=0.55). The median difference between the ECG QTc and the monitor QTc (ECG QTc minus monitor QTc) was -7ms (IQR -23 to 11ms). CONCLUSION: We found that there was moderate correlation between the QTc reported on the 12 lead ECG and that reported by the bedside monitor. This correlation is not strong enough to support the use of the bedside monitor as a substitute for the 12­lead ECG when evaluating a patient's QTc.

Anthropometric Evaluation of Periorbital Region and Facial Projection Using Three-Dimensional Photogrammetry.

INTRODUCTION: Direct anthropometric and three-dimensional (3D) photogrammetry measurements have been used extensively in cleft/craniofacial surgery to assess morphological changes and surgical outcomes. Craniofacial procedures alter the sagittal projection of periorbital bony prominences. Mulliken described a method of measuring their projection relative to the corneal plane but is impractical in clinical practice. Three-dimensional photogrammetry may offer a solution; however, the cornea is not visualized on this. The authors propose to develop new normative measurements of facial projection relative to the pupil. METHODS: Five 3D photographs were taken of 5 individuals using Vectra M5 camera. Facial projection measurements were taken of the sagittal projection of the bilateral periorbital landmarks and nasal radix relative to the pupil using Mirror 3D analysis. Standard deviations (SD) were determined for each subject and laterality. Chi-square tests confirmed all SD <1 mm. Intra and inter-rater reliability were confirmed with an intraclass correlation coefficient assessment. RESULTS: Three male and 2 female subjects were photographed with 5 unique images. Standard deviations of repeat measures of all landmarks were <0.5 mm. Chi-square tests confirmed with statistical significance that SD for all values except for the radix was <1 mm (P<0.05). Intrarater reliability was high for all landmarks (intraclass correlation coefficient coefficients 0.93-0.99). Inter-rater reliability was good for the lateral canthi and excellent for all others. CONCLUSION: This technique demonstrates repeatability with high reliability on serial photographs and is applicable to measuring surgery effects and growth on facial projection. Establishment of age-specific normative values for landmark projection will refine usage applicability in operative planning.

Massive diltiazem and metoprolol overdose rescued with extracorporeal life support.

The management of overdoses of cardioactive medications in the emergency department can be challenging. The reversal of severe toxicity from one or more types of cardioactive medication may fail maximal medical therapies and require extreme invasive measures such as transvenous cardiac pacing and extracorporeal life support. We present a case of massive diltiazem and metoprolol overdose refractory to maximal medical therapy, including intravenous calcium, glucagon, vasopressors, high dose insulin, and lipid emulsion. The patient experienced refractory bradydysrhythmia that responded only to transvenous pacing. Extracorporeal life support was initiated and resulted in successful organ perfusion and complete recovery of the patient. This case highlights the potential utility of extracorporeal life support in cases of severe toxicity due to multiple cardioactive medications.

Role of nutraceuticals in dementia care.

With an increase in the number of patients diagnosed with Alzheimer's disease, it is not surprising that there is a consistent increase in use of nutraceuticals and other over-the-counter medications to combat memory complaints and ideally treat dementia. Throughout this review article, the authors highlight recent literature updates on B vitamins, vitamin D, vitamin E, omega-3 fatty acids, and gingko biloba. Similar to any other medication, it is imperative to evaluate the risks and benefits in older patients, especially in light of comorbidities and existing medications.

Sepsis in obstetrics: cause, prevention, and treatment.

PURPOSE OF REVIEW: The aim of the study was to provide a summary of recent guidance on sepsis in obstetrics. RECENT FINDINGS: Morbidity and mortality from sepsis is increasing in the UK and other developed countries. In many cases, care has been found to be substandard. Common themes are a failure to recognize and respond to the sick woman and inadequate antibiotic and fluid management in the septic parturient. SUMMARY: Increased awareness of obstetric sepsis is required. Women and their families need to be informed about it and staff must have the skills and competencies to recognize this early. The management of severe sepsis in obstetrics is multidisciplinary. Implementation of the goals of the Surviving Sepsis Campaign into obstetric practice is important to improve outcomes. More research is needed to validate the parameters used in this and early warning scores for the obstetric population.

Predicting chronological age based on age-related osteophyte development in the superior and inferior vertebral centrum margins of T12-L5.

The purpose of this study was to determine the relationship between vertebral margins at individual vertebral levels between T12-L5 vertebra and chronological age and develop predictive models. Three hundred and nineteen CT scans from a medical imaging database in North America were randomly selected. Three superior and inferior vertebral margin sites were scored based on observable age-related changes. All individual vertebral margin site scores significantly correlated with age at death with Pearson r values ranging from 0.47 to 0.77. Totaling the individual vertebral margin site scores for L1-L5 improved Pearson r to 0.92. All resulting predictive models were significant, and the best models predicted age at death within 10 years 70%-76% of the time for males, females, and combined male and females. In conclusion, this study produced accurate and reliable models to predict age at death using age-related changes in the spine for a North American population.

Embolized Watchman Removal With Modified Hangman Technique.

In this case report, we explore a novel technique to remove an embolized Watchman device (Boston Scientific) into the thoracic aorta endovascularly. The technique involves a wire + snare combination that is threaded through the metal struts of the Watchman. This combination technique along with the threading provides increased stability during removal and decreases the risk of the Watchman slipping from the devices and causing further embolization. Further work is required to elucidate the efficacy of this technique in other scenarios.

Effect of low-osmolality intravenous contrast on serum osmolal gap in adults.

BACKGROUND: Contrast media used today is considered "low-osmolality." No study has evaluated the effect of intravenous contrast media on the measurement of the osmolal gap in adult patients. OBJECTIVE: To determine if "low-osmolality" intravenous contrast media administered to adult patients undergoing computed tomography (CT) of the abdomen and pelvis affects the osmolal gap. METHODS: We performed a prospective pilot study in the Emergency Department of a university-affiliated tertiary care center. Patients were enrolled if they were age ≥18 years and <60 years and the treatment team had ordered an abdomen and pelvis CT with intravenous (i.v.) contrast procedure and a serum basic metabolic panel (BMP) that included serum glucose, blood urea nitrogen, and sodium. Once enrolled, a serum osmolality and serum ethanol level was ordered and obtained on the same blood draw as the BMP before the CT. Patients were excluded if they had detectable ethanol on laboratory screen, if they were suspected to have ingested methanol, ethylene glycol, isopropanol, mannitol, or underwent CT with i.v. contrast within the prior 24 h. Paired samples were compared using the Wilcoxon signed-rank test. RESULTS: Of the 100 patients screened, 18 patients were lost due to withdrawal of consent or missing data. The median of the osmolal gap pre-CT was 8.18 with an interquartile range of 4.76-11.15. The median of the osmolal gap post-CT was 11.23 with an interquartile range of 7.29-14.83. The difference in the osmolal gap was a median of 2.34 (p = 0.0003) with an interquartile range of -1.32-5.97. CONCLUSION: Although the effect in our study was small, clinicians should be aware of the ability of contrast media to increase the osmolal gap.

Arteriovenous malformation of the small intestine presenting with a transfusion-dependent anaemia in pregnancy.

Gastrointestinal bleeding that originates in the small intestine is often difficult to diagnose. Bleeding from a small intestinal arteriovenous malformation (AVM) is rare, with congenital AVMs more commonly located in the rectum or sigmoid. There is a relative paucity of cases reported in the literature. In the gastrointestinal tract, it can cause acute and chronic bleeding, which can be fatal. Although the incidence of small bowel AVMs is quite low, such lesions can be identified as the bleeding source in patients with obscure gastrointestinal bleeding (OGIB) harbouring severe, transfusion-dependent anaemia. It can be exceedingly difficult to localise and diagnose gastrointestinal tract bleeding, particularly in cases of occult small bowel AVMs. CT angiography and capsule endoscopy can help to establish the diagnosis. Laparoscopy is an appropriate and beneficial treatment modality for small bowel resection. The authors present the case of a primigravida woman in her late 20s diagnosed with a symptomatic transfusion-dependent anaemia during her pregnancy. She developed OGIB and despite no history of chronic liver disease became encephalopathic. Due to her physical deterioration and uncertain diagnosis, her caesarean section was performed at 36+6 weeks to expedite investigations and treatment. She was diagnosed with a jejunal AVM and underwent coiled embolisation of her superior mesenteric artery. She became haemodynamically unstable and underwent a laparotomy and small bowel resection. A full non-invasive liver screen was negative, however, her MRI liver described multiple focal nodular hyperplasia (FNH) lesions raising the possibility of FNH syndrome in the context of a previous AVM malformation. A prompt stepwise, multimodality diagnostic approach is required to prevent patient morbidity and mortality.