Cadaveric Subjects Research Articles

Typology of Terminal Colon at the Chu of Point G in Bamako

Purpose: To describe the morphometric types of the terminal colon. Patients and Methods: This was an anatomical study by laparotomy for the terminal colon on 7 living subjects and by anatomical dissection on 8 fresh cadaveric subjects in the department of surgery B of the CHU of Point G and in the anatomy laboratory of the faculties of medicine of odonto-stomatology (FMOS) and pharmacy (FAPH) of Bamako from January 1, 2018 to December 31, 2019 or 2 years. Patients without a mass on the terminal recto-colonic junction or volvulus of the terminal colon or abdominopelvic mass on the terminal colon and fresh cadavers declared unknown without a laparotomy scar coming from Bamako University Hospitals or Reference Centers (CS Réf) were included in this study. Results: We investigated 15 cases, including 7 live cases and 8 cadavers. Males accounted for 60% (n=9) and females 40% (n=6), i.e. a sex ratio of 1.5. Mean age was 47.14 ±15.57 years. The mean length of the terminal colon was 41.79 cm±13.37. The mean length of the terminal mesocolon was 11.18 cm. The maximum height of the terminal mesocolon averaged 10.70 cm ± 3.61 cm. There were 46.72% (n=7) medium-form cases, 33.30% (n=5) short-form cases and 19.98% (n=3) long-form cases. Conclusion: The terminal colon can be short, medium or long, depending on its length and the height of its meso.

Utility of Handheld Ultrasound in Identifying Millimeter-Sized Vasculature in Living and Cadaveric Subjects.

Objective This study aimsto investigate the utility of handheld, Bluetooth-capable ultrasound in identifying millimeter-sized vasculature in both living and cadaveric subjects. Methods Using handheld, linear ultrasound probes, the carpal tunnel of 87 living individuals (174 forearms) was assessed for the presence of a persistent median artery (PMA). Radial, ulnar, and persistent median arterial diameters were measured, along with forearm circumference. Using the same probes, 46 cadaveric forearms were assessed for the presence of a "potential" PMA. Those same forearms were subsequently dissected to confirm the presence of the artery. Results A PMA was identified in 3.4% of individuals (1.7% of forearms). Radial, ulnar, and persistent median arterial diameters were 2.12 ± 0.40 mm, 1.89 ± 0.41 mm, and 0.82 ± 0.33 mm, respectively. The radial artery was significantly larger than the ulnar artery (p < 0.0001). In cadaveric subjects, four "potential" PMAs were identified by pre-dissection ultrasound. Upon dissection, only one of the "potential" PMAs was confirmed, and three previously unidentified PMAs were identified. Conclusions The prevalence of PMA in living subjects was lower than previously reported. Additionally, handheld ultrasound had low accuracy in identifying PMAs in cadavers prior to dissection. This could be an indication that current handheld ultrasound lacks the sensitivity to identify millimeter-sized vasculature, such as a PMA. In both populations of subjects, key, non-anomalous anatomy was readily seen, indicating the utility of handheld ultrasound in the proper context.

Mesenteric sparing approach for advanced nodal extent in small intestinal neuroendocrine tumors. Is there a limit to the vascular resection in order to avoid creating a short small bowel syndrome? An anatomic research study.

By selectively perfusing the first three jejunal arteries (JA), we aim to assess the individual perfusion length of small bowel (SB) and its impact on nodal resection in stage III-up small-intestinal neuroendocrine tumors (SI-NET). Our anatomical research protocol implies a midline laparotomy and three measures of the SB length. We then perform a classical anterior approach of the superior mesenteric vessels. We carry on with the complete dissection and checking of the superior mesenteric artery (SMA) in order to identify the first three JA. Then we selectively perfuse each artery with colored latex solutions and measure the length of small bowel perfused respectively. We conducted our protocol on six cadaveric subjects. Mean(SD) SB length was 413(5.7), 535(13.2), 485(15), 353(25.1), 730(17.3) and 525(16° cm respectively from subject one to six. Most JA originated from the left side of the SMA. The first JA originated from its posterior wall in two subjects. Mean(SD) distance of origin of the first three JA was 4.6(1.3)cm, 6(1.1)cm and 7.1(0.9)cm respectively. Mean(SD) diameter of SMA was 10.8(3.3)mm. Mean diameter of the three first JA was 4(1.4)mm, 4(1.5)mm and 5(1.2)mm respectively. Mean(SD) SB length perfused by first and second JA was 224(14.9)cm, 175(8.6)cm, 238.3(7.6)cm, 84.3(5.1)cm, 233.3(5.8)cm and 218.3(10.4)cm respectively from subject one to six. We observed a trend suggesting that the first and second JA may sustain a SB length beyond the viable 1.5m limit, implying the feasibility of stage III-up SI-NET resection with just two JA.

Flexor Hallucis Longus decompression under ultrasound guidance: A cadaver study

IntroductionThe Flexor Hallucis Longus (FHL) is a muscle that can be subject to multiple impingements caused by exaggerated plantar flexion in athletes. The most common impingement is due to inflammation of the tendon at the retrotalar pulley. The constraints exerted on the FHL are responsible for a pathology called functional Hallux Limitus. Surgical treatment consists of tenolysis of the FHL arthroscopically or via open surgery, by opening the pulley. The objective of this study was to evaluate the risk of lesions of the neurovascular pedicle and the posterior tibial tendon after tenolysis of the Flexor Hallucis Longus under ultrasound guidance. HypothesisThe hypothesis of this study is that tenolysis of the Flexor Hallucis Longus could proceed under ultrasound guidance without associated tendon lesions or neurovascular lesions. Material and methodsThirteen cadaveric specimens were studied, resulting in an analysis of 26 feet. Following identification of the Flexor Hallucis Longus, tenolysis with a 19-gauge needle under ultrasound guidance was performed by an orthopedic specialist after hydrodissection to push back the posterior tibial pedicle. The dissection of the cadavers made it possible to verify the positioning of the posterior tibial pedicle, the FHL tendon and the opening of the retrotalar pulley. ResultsFive cadaveric subjects, 10 cases, underwent a complete opening of the retrotalar pulley under ultrasound guidance. In 16 cases, the opening was partial, with a section of the pulley of 65.87±18%. The cases of partial openings showed no neurovascular or tendinous lesions. The 10 cases of complete opening resulted in 5 lesions of the tibial nerve, 4 vascular lesions: 1 venous and 3 arterial, and 6 lesions of the FHL tendon. ConclusionTenolysis of the Flexor Hallucis Longus under ultrasound guidance at the level of its retrotalar pulley was systematically associated with neurovascular lesions in the event of complete release of the pulley by the method studied, unlike a partial release where no lesion was found. Level of EvidenceIII; case-control study.

Investigating keypoint descriptors for camera relocalization in endoscopy surgery.

Recent advances in computer vision and machine learning have resulted in endoscopic video-based solutions for dense reconstruction of the anatomy. To effectively use these systems in surgical navigation, a reliable image-based technique is required to constantly track the endoscopic camera's position within the anatomy, despite frequent removal and re-insertion. In this work, we investigate the use of recent learning-based keypoint descriptors for six degree-of-freedom camera pose estimation in intraoperative endoscopic sequences and under changes in anatomy due to surgical resection. Our method employs a dense structure from motion (SfM) reconstruction of the preoperative anatomy, obtained with a state-of-the-art patient-specific learning-based descriptor. During the reconstruction step, each estimated 3D point is associated with a descriptor. This information is employed in the intraoperative sequences to establish 2D-3D correspondences for Perspective-n-Point (PnP) camera pose estimation. We evaluate this method in six intraoperative sequences that include anatomical modifications obtained from two cadaveric subjects. Show that this approach led to translation and rotation errors of 3.9mm and 0.2radians, respectively, with 21.86% of localized cameras averaged over the six sequences. In comparison to an additional learning-based descriptor (HardNet++), the selected descriptor can achieve a better percentage of localized cameras with similar pose estimation performance. We further discussed potential error causes and limitations of the proposed approach. Patient-specific learning-based descriptors can relocalize images that are well distributed across the inspected anatomy, even where the anatomy is modified. However, camera relocalization in endoscopic sequences remains a persistently challenging problem, and future research is necessary to increase the robustness and accuracy of this technique.

Alternatives to DEXA for the assessment of bone density: a systematic review of the literature and future recommendations.

Osteoporosis has significant implications in spine fusion surgery, for which reduced spinal bone mineral density (BMD) can result in complications and poorer outcomes. Currently, dual-energy x-ray absorptiometry (DEXA) is the gold standard for radiographic diagnosis of osteoporosis, although DEXA accuracy may be limited by the presence of degenerative spinal pathology. In recent years, there has been an evolving interest in using alternative imaging, including CT and MRI, to assess BMD. In this systematic review of the literature, the authors assessed the use and effectiveness of MRI, opportunistic CT (oCT), and quantitative CT (qCT) to measure BMD. In accordance with the PRISMA guidelines, the authors conducted a systematic search for articles posted on PubMed between the years 2000 and 2022 by using the keywords "opportunistic CT, quantitative CT, MRI" AND "bone density" AND "spine." Inclusion criteria consisted of articles written in English that reported studies pertaining to human or cadaveric subjects, and studies including a measure of spinal BMD. Articles not related to spinal BMD, osteoporosis, or spinal surgery or reports of studies that did not include the use of spinal MRI or CT were excluded. Key study outcomes were extracted from included articles, and qualitative analysis was subsequently performed. The literature search yielded 302 articles. Forty-two articles reported studies that met the final inclusion criteria. Eighteen studies utilized MRI protocols to correlate spinal BMD with vertebral bone quality scores, M-scores, and quantitative perfusion markers. Eight studies correlated oCT with spinal BMD, and 16 studies correlated qCT with spinal BMD. With oCT and qCT imaging, there was consensus that Hounsfield unit (HU) values > 160 demonstrated significant reduction in risk of osteoporosis, whereas HU values < 110 were significantly correlated with osteoporosis. Osteoporosis is increasingly recognized as a significant risk factor for complications after spinal fusion surgery. Consequently, preoperative assessment of BMD is a critical factor to consider in planning surgical treatment. Although DEXA has been the gold standard for BMD measurement, other imaging modalities, including MRI, oCT, and qCT, appear to be viable alternatives and may offer cost and time savings.

Postulating a pathophysiological association between hallux valgus and plantar venous thrombosis through cadaveric dissections – Geometric measurements pedobarographic and phlebology correlates and literature review

This original article postulates a pathophysiological association between two uncommon clinical entities in a cadaveric subject. A female cadaver from a willed body donor was procured for educational and research purposes. During surgical dissection, the subject was observed to have hallux valgus (HV) and lateral plantar venous thrombosis (PVT) on the left foot. Clinical significance of HV was confirmed by geometric measurements of the great toe and first metatarsal. Severity of lateral PVT was established by meticulous dissection along full course of the vein and all its grossly accessible tributaries. Dissections in other regions of the same cadaveric subject did not reveal evidence of venous thrombosis elsewhere. Extensive search of the contemporary literature confirmed HV is most common in elderly females, though not very common in the general population. It also established that isolated PVT is very rare, the medial type being rarer. No study mentioned both HV and PVT in the same subject or tried to establish a pathophysiological association between both entities. Analyzing the pedobarographic and phlebology literature on HV, PVT, foot veins, gait, posture, and foot pressure points led the authors to postulate that flattening of medial arch and increased medial forefoot pressure from HV during life in elderly females could render Uhl-Gillot’s postulated ‘footpump’ incompetent. Since the principal conduit of the foot-pump is the lateral plantar vein (LPV), ineffective foot-pump could lead to lateral PVT. Considering the paucity of literature on coexisting HV and PVT in living and cadaveric subjects, more studies are required to confirm our hypothesis of this pathophysiological association.

Layer-Specific Tensile Strength of the Human Aorta: Segmental Variations.

Knowledge of the failure properties of the aorta is essential to understand the mechanisms of dissection and rupture. Limited information is, however, available in humans or experimental animals about the layer-specific properties and their segmental variations have not been determined. In this paper, the failure properties of the intima, media, and adventitia were studied in nine consecutive aortic segments and two principal directions. Detailed biomechanical tests were performed with a tensile-testing device on 756 layer strips, harvested from fourteen cadaveric subjects aged 21-82 years. Intimal and medial strength in either direction remained invariant along the aorta, and their extensibility longitudinally decreased, whereas adventitial strength and extensibility longitudinally increased, explaining why the preferential sites for the development of aortic dissection or traumatic rupture are in the proximal aorta. The media was stronger circumferentially than longitudinally in all segments, accounting for the typically transverse tearing in dissection/rupture. The adventitial properties were significantly higher than the intimal and medial in most segments. Still, the intima had similar strength but lower extensibility compared to the media in both directions, and higher maximum stiffness longitudinally in several segments. The rupture surface of all layers was not perpendicular to the loading axis, more so in the circumferential strips compared to longitudinal ones. Aging impaired the extensibility and strength of all layers, particularly the media, but did not affect the maximum stiffness and rupture-surface direction. Females were rarely associated with different failure properties compared to age-matched males.

Regional delamination strength in the human aorta underlies the anatomical localization of the dissection channel

Aortic dissection is a life-threatening event, during which a primary tear propagates along the aorta causing catastrophic delamination of the inner (intima with most of the media) from the outer layers (leftover media with adventitia). Our understanding of mode-I fracture resistance at different aortic regions is incomplete, although the anatomical localization of the dissection channel may be assigned to this factor. To determine whether the susceptibility to dissection propagation varied with aortic region, the average and standard deviation of peel tension (indices of adhesive strength between layers when pulled apart and its fluctuation) were measured in 24 cadaveric subjects. Measurements were made in the inner and outer quadrants of 9 consecutive regions. Strong regional heterogeneity was established that was age-related based on the following evidence: (1) the average and standard deviation of peel tension peaked in the ascending aorta, decreasing to almost constant values in the descending thoracic aorta, but increasing across the abdominal aorta; (2) axial differences were more pronounced in the inner quadrant, with differences among quadrants reaching significance proximally; (3) the average peel tension was greatly impaired from <40 to 40–60 but much less to >60-year-old subjects at most regions/quadrants, leading to non-uniform axial variations in all age groups; (4) gender affected little the data. This comprehensive series of delamination tests explains the clinical observation of most dissections initiating in the ascending aorta to extend distally and of few dissections initiating in the descending thoracic aorta to extend proximally, while supporting the increased vulnerability in aged subjects.

Sternocleidomastoid Tendon as a Consistent Landmark for Identifying the Spinal Accessory Nerve: A Case Series.

ObjectiveWe propose a standardized approach of using the tendon of the sternocleidomastoid (SCM) muscle to locate the spinal accessory nerve (SAN) in neck dissection.Study DesignCross-sectional anatomic study.SettingTertiary academic medical center.MethodsAdult patients aged ≥18 years undergoing primary neck dissection for head and neck cancer were included. Anatomic measurements included the length of the SCM tendon, the distance from the mastoid tip to the entrance of the SAN into the SCM, the distance from the SAN to the distal edge of the SCM tendon, and the perpendicular distance from the anterior edge of the SCM to the SAN. Five cadaveric specimens also underwent bilateral modified radical neck dissections with the same anatomic measurements taken.ResultsTwenty-two living subjects and 5 cadavers were included. No statistical correlation was noted between patient demographics and any measurement. The mean (SD) length of the SCM tendon was 63.7 mm (11.8) in living subjects and 61.5 mm (10.4) in cadaveric specimens. The average distance from the mastoid tip to the entrance of SAN into the SCM was 51.6 mm (12.2) in living subjects and 51.6 mm (7.1) in cadaveric subjects. The distance of the SAN insertion into the SCM muscle from the anterior edge was 8.9 mm (3.4) in living subjects and 16.2 mm (7.2) in cadaver specimens. Laterality was compared in the cadaveric specimens; there was no statistically significant difference in any of the measurements between sides.ConclusionThis study demonstrates the SCM tendon to be a reliable and safe surgical landmark to identify and preserve the SAN during neck dissection.

Surgical Techniques for Thoracolumbar Spine Fractures: WFNS Spine Committee Recommendations.

To formulate the specific guidelines for the recommendation of thoracolumbar fracture regarding surgical techniques and nonfusion surgery. WFNS (World Federation of Neurosurgical Societies) Spine Committee organized 2 consensus meeting. For nonfusion surgery and thoracolumbar fracture, a systematic literature search in PubMed and Google Scholar database was done from 2010 to 2020. The search was further refined by excluding the articles which were duplicate, not in English or were based on animal or cadaveric subjects. After thorough shortlisting, only 50 articles were selected for full review in this consensus meeting. To generate a consensus, the levels of agreement or disagreement on each item were voted independently in a blind fashion through a Likert-type scale from 1 to 5. The consensus was achieved when the sum for disagreement or agreement was ≥ 66%. Each consensus point was clearly defined with evidence strength, recommendation grade, and consensus level provided. A magnitude of prospective papers were analyzed to formulate consensus on various surgical techniques that can be employed to address different types of thoracolumbar fractures. Surgical treatment of thoracolumbar fractures can be a better option over the nonoperative approach, especially for those who cannot tolerate months in an orthosis or cast, such as those with multiple extremity injuries, skin lesions, obesity, and so forth. It generally allows early mobilization, less hospital stay, reduced pulmonary complications, and better correction of sagittal balance. Current available literature fails to demonstrate any statistically significant benefit of fusion surgery over nonfusion in thoracolumbar fractures.

Mandibular magnetic distractor: preclinical validation

The feasibility of magnetic activation for mandibular distraction has been demonstrated previously. In this study, we developed a biocompatible device to evaluate the feasibility of distraction in cadaveric subjects and the functionality of the device in bench tests. To confirm, considering the dimension of the distractor, that the torque applied on the internal magnet would be sufficient to activate distraction osteogenesis we measured, for different distances, the transmitted torque between a magnet (internal and external). We evaluated the friction force of the device, and the resilience of the magnet to the sterilisation process. To confirm the feasibility of distraction with this device, we proceeded to cadaveric tests, and evaluated the satisfaction of four surgeons. The force applied to the moving plate was greater than 50 Newtons (N) with a friction coefficient of η=0.2. We determined a friction torque of 65.10-3 N.mm in the distractor mechanism and demonstrated that sterilisation did not alter the magnet. Mandibular distraction had been successfully achieved in cadaveric trials, and surgeons were satisfied. This new device could be implanted in human subjects, for clinical assay, after approval by the regulatory agencies. The use of this fully internalised device should improve patients’ comfort.

Polycarbonate-urethane coating can significantly improve talus implant contact characteristics

Talus implants can be utilized in cases of talus avascular necrosis and has been regarded as a promising treatment method. However, existing implants are made of stiff materials that directly oppose natural cartilage. The risk of long-term cartilage wear and bone fracture from the interaction between the cartilage and stiff implant surfaces has been documented in post-hemiarthroplasty of the hip, knee and ankle joints.The aim is to explore the effects of adding a layer of compliant material (polycarbonate-urethane; PCU) over a stiff material (cobalt chromium) in talus implants. To do so, we obtained initial ankle geometry from four cadaveric subjects in neutral standing to create the finite element models. We simulated seven models for each subject: three different types of talus implants, each coated with and without PCU, and a biological model. In total, we constructed 28 finite element models. By comparing the contact characteristics of the implant models with their respective biological model counterparts, our results showed that PCU coated implants have comparable contact area and contact pressure to the biological models, whereas stiff material implants without the PCU coating all have relatively higher contact pressure and smaller contact areas. These results confirmed that adding a layer of compliant material coating reduces the contact pressure and increases the contact area which in turn reduces the risk of cartilage wear and bone fracture. The results also suggest that there can be clinical benefits of adding a layer of compliant material coating on existing stiff material implants, and can provide valuable information towards the design of more biofidelic implants in the future.

The Lack of Sex, Age, and Anthropometric Diversity in Neck Biomechanical Data.

Female, elderly, and obese individuals are at greater risk than male, young, and non-obese individuals for neck injury in otherwise equivalent automotive collisions. The development of effective safety technologies to protect all occupants requires high quality data from a range of biomechanical test subjects representative of the population at risk. Here we sought to quantify the demographic characteristics of the volunteers and post-mortem human subjects (PMHSs) used to create the available biomechanical data for the human neck during automotive impacts. A systematic literature and database search was conducted to identify kinematic data that could be used to characterize the neck response to inertial loading or direct head/body impacts. We compiled the sex, age, height, weight, and body mass index (BMI) for 999 volunteers and 110 PMHSs exposed to 5,431 impacts extracted from 63 published studies and three databases, and then compared the distributions of these parameters to reference data drawn from the neck-injured, fatally-injured, and general populations. We found that the neck biomechanical data were biased toward males, the volunteer data were younger, and the PMHS data were older than the reference populations. Other smaller biases were also noted, particularly within female distributions, in the height, weight, and BMI distributions relative to the neck-injured populations. It is vital to increase the diversity of volunteer and cadaveric test subjects in future studies in order to fill the gaps in the current neck biomechanical data. This increased diversity will provide critical data to address existing inequities in automotive and other safety technologies.

Anatomical basis for ultrasound-guided infiltration of the saphenous nerve in the subsartorial canal.

The present work is aimed studying the visibility and position of the vasto-adductor membrane with ultrasonography and demonstrating that injection performed under this membrane allows to infiltrate the saphenous nerve. It was analyzed with ultrasonography in four cadaveric subjects and in 13 volunteers. This membrane was clearly visible and methylene blue was located underneath it after injection in all cadaveric subjects. This study demonstrates that it can be used as a reliable anatomic landmark when performing an injection for both regional anesthesia and in the treatment of saphenous nerve tunnel syndrome.

Recent Advances in the Generation of β-Cells from Induced Pluripotent Stem Cells as a Potential Cure for Diabetes Mellitus.

Diabetes mellitus (DM) is a group of metabolic disorders characterized by high blood glucose levels due to insufficient insulin secretion, insulin action, or both. The present-day solution to diabetes mellitus includes regular administration of insulin, which brings about many medical complications in diabetic patients. Although islet transplantation from cadaveric subjects was proposed to be a permanent cure, the increased risk of infections, the need for immunosuppressive drugs, and their unavailability had restricted its use. To overcome this, the generation of renewable and transplantable β-cells derived from autologous induced pluripotent stem cells (iPSCs) has gained enormous interest as a potential therapeutic strategy to treat diabetes mellitus permanently. To date, extensive research has been undertaken to derive transplantable insulin-producing β-cells (iβ-cells) from iPSCs in vitro by recapitulating the in vivo developmental process of the pancreas. This in vivo developmental process relies on transcription factors, signaling molecules, growth factors, and culture microenvironment. This review highlights the various factors facilitating the generation of mature β-cells from iPSCs. Moreover, this review also describes the generation of pancreatic progenitors and β-cells from diabetic patient-specific iPSCs, exploring the potential of the diabetes disease model and drug discovery. In addition, the applications of genome editing strategies have also been discussed to achieve patient-specific diabetes cell therapy. Last, we have discussed the current challenges and prospects of iPSC-derived β-cells to improve the relative efficacy of the available treatment of diabetes mellitus.

Sectioned and segmented images of the male whole body, female whole body, male head, and female pelvis from the Visible Korean.

In the Visible Korean, serially sectioned images with real color and high resolution have been prepared from four cadaveric subjects: male whole body, female whole body, male head, and female pelvis. Recently, segmented images of the female whole body were manufactured, permitting the distribution of the complete four data sets. The purpose of this report was to promote the applications of sectioned and segmented images from the Visible Korean by announcing them. Reduced image data were loaded to self-developed browsing software; using the browsing software, the contents could be quickly grasped and evaluated by other investigators. The four data sets were compared to disclose the individual merits and demerits. The sectioned and segmented images showed the possibility to be used to reconstruct the stereoscopic volume and surface models of body structures. The Visible Korean is expected to contribute to the interactive simulation of medical learning and clinical practice.

Nasal Airflow Changes With Bioabsorbable Implant, Butterfly, and Spreader Grafts.

Internal nasal valve compromise is a major cause of nasal obstruction, with a growing number of ways to treat this condition. In this study, we compared the effects of butterfly graft, spreader graft, and the bioabsorbable nasal implant on nasal airflow resistance. Cadaver study. Computational fluid dynamics (CFD) simulations were completed from nine preoperative and postoperative cadaveric subjects. Each cadaveric head underwent placement of a bioabsorbable nasal implant (BNI) (Spirox Latera; Stryker ENT, Plymouth, MN), butterfly graft, or spreader graft. Pre- and postoperative computed tomography (CT) scans were used to generate three-dimensional models of the nasal airway used in steady-state CFD simulations of airflow and heat transfer during inspiration. Butterfly graft placement resulted in a mean improvement in nasal airway resistance of 24.9% (±7.3), whereas BNI placement resulted in a 6.7% (±1.2) improvement, and spreader graft placement also resulted in a consistent improvement of 2.6% (±13.5). Pressure within the main nasal cavity was consistently lower following butterfly graft placement versus a spreader graft or BNI. Butterfly and spreader graft placement also resulted in modest improvements in airflow allocation, whereas BNI demonstrated more variation (-1% to 12%). Heat flux was not significantly different; however, a small improvement in total heat flux was seen with all three interventions. The results of this study demonstrate reduction in nasal airway resistance in all three surgical interventions, with the butterfly graft demonstrating superiority to the other two techniques. However, these data only reflect a static environment and not dynamic changes in airflow seen during respiration. NA Laryngoscope, 130:E817-E823, 2020.

In Vivo Small Bowel Length is Longer than in Formalin-Fixed Cadavers

SBL was measured prospectively in 167 formalin-fixed cadavers; and studied in 118 without intestinal surgery. A standardized and reproducible method of small bowel measurement was utilized in both <em>in vivo</em> and cadaveric subjects. Small bowel was measured in situ from the Ligament of Treitz to the ileocecal valve. These measurements were compared to previously published cadaveric and <em>in vivo</em> human SBL data. The number of cadavers examined was larger than in other published studies; the number of <em>in vivo</em> subjects was also the highest yet reported.

The Roles of Celiac Trunk Angle and Vertebral Origin in Median Arcuate Ligament Syndrome

Median arcuate ligament syndrome (MALS) is a rarely diagnosed condition resulting from compression of the celiac trunk (CT) by the median arcuate ligament (MAL) of the diaphragm. Ischemia due to reduced blood flow through the CT and/or neuropathic pain resulting from celiac ganglion compression may result in a range of gastrointestinal symptoms, including nausea, postprandial discomfort, and weight loss. However, the mechanism of compression and its anatomical correlates have been incompletely delineated. It has been hypothesized that CT angle of origination may be more acute in individuals with MALS. Here, frequency of anatomical variation in the MAL and CT were assessed in 35 cadaveric subjects (17M/18F), including the vertebral level of origin of CT and superior mesenteric artery (SMA), the distance between CT and MAL and SMA, the angles of origination of CT and SMA, the diameter at the CT base, and MAL/CT overlap. Females exhibited significantly higher rates of inferred MAL/CT overlap than males. Significant correlations were revealed between MAL/CT overlap and angles of origination of the CT and SMA. Vertebral level of origin of the CT in individuals with MAL/CT overlap was not significantly more superior than in those without. This study also revealed a significant relationship between MAL/CT overlap and angle of origination of the CT, which has clinical implications for understanding the anatomy associated with MALS.