The Ability to Sustain Facial Expressions.

To gain more insight into facial muscle function, imaging during action would be optimal. Magnetic resonance imaging is highly suitable for visualizing facial muscles. However, magnetic resonance imaging requires the individual to remain as still as possible for a while. Knowledge of the ability to sustain facial expressions is requisite before scanning individuals. This could help adapting the scanning protocol to obtain optimal quality of imaging the muscles in action. A study, including 10 healthy volunteers, was done to perceive the extent of movement while holding facial expressions of smiling and pouting. During 6 minutes, 3-dimensional photographs were taken every consecutive minute while the participants maintained their facial expressions as motionless as possible. The movement was objectified by creating distance maps between the 2 models and calculating the Root Mean Square using the software 3DMedX. The results showed that most movements occurred in the first minute, with a decrease of the intensity of the expression. After the first minute, the expression, although less intense, could be held stable. This implies that magnetic resonance imaging scanning during facial expression is possible, provided that the scanning starts after the first minute has elapsed. In addition, results demonstrated that more slackening of the muscles while smiling compared with pouting.

A novel anatomical description of the esophagus: the supracarinal mesoesophagus.

BACKGROUND: During thoracoscopic esophageal resection, while performing the supracarinal lymphadenectomy along the left recurrent laryngeal nerve (LRLN) from the aortic arch to the thoracic apex, we observed a not previously described bilayered fascia-like structure, serving as prolongation of the already known mesoesophagus. METHODS: We retrospectively evaluated 70 consecutively unedited videos of thoracoscopic interventions on esophageal resections for cancer, in order to determine the validity of this finding and to describe its utility for performing a systematic and more accurate dissection of the LRLN and its adequate lymphadenectomy. RESULTS: After mobilization of the upper esophagus from the trachea and tilting the esophagus by means of two ribbons, a bilayered fascia was observed between the esophagus and the left subclavian artery in 63 of the 70 patients included in this study. By opening the right layer, the left recurrent nerve became visualized and could be dissected free in its whole trajectory. Vessels and branches of the LRLN were divided between miniclips. Mobilizing the esophagus to the right, the base of this fascia could be found at the left subclavian artery. After dissecting and clipping the thoracic duct, complete lymphadenectomy of 2 and 4L stations could be performed. Mobilizing the esophagus in distal direction, the fascia continued at the level of the aortic arch, where it had to be divided in order to mobilize the esophagus from the left bronchus. Here, a lymphadenectomy of the aorta-pulmonary window lymph nodes (station 8) can be performed. It seems that from there the fascia continued without interruption with the previously described mesoesophagus between the thoracic aorta and the esophagus. CONCLUSIONS: Here we described the concept of the supracarinal mesoesophagus on the left side. Applying the description of the mesoesophagus will create a better understanding of the supracarinal anatomy, leading to a more adequate and reproducible surgery.

Eversion technique versus traditional carotid endarterectomy with patch angioplasty: a systematic review with meta-analyses and trial sequential analysis.

Introduction: The use of an 'eversion' technique is not unequivocally proven to be superior to carotid endarterectomy with patch angioplasty. An up-to-date systematic review is needed for evaluation of benefits and harms of these two techniques. Methods: RCTs comparing eversion technique versus endarterectomy with patch angioplasty in patients with a symptomatic and significant (≥50 %) stenosis of the internal carotid artery were enrolled. Primary outcomes were all-cause mortality rate, health-related quality of life and serious adverse events. Secondary outcomes included 30-day stroke and mortality rate, (a) symptomatic arterial occlusion or restenosis, and adverse events not critical for decision making. Results: Four RCTs were included with 1272 surgical procedures for carotid stenosis; eversion technique n = 643 and carotid endarterectomy with patch closure n = 629. Meta-analysis comparing both techniques showed, with a very low certainty of evidence, that eversion technique might decrease the number of patients with serious adverse events (RR 0.47; 95% CI 0.34 to 0.64; p ≤ 0.01). However, no difference was found on the other outcomes. TSA demonstrated that the required information sizes were far from being reached for these patient-important outcomes. All patient-relevant outcomes were at low certainty of evidence according to GRADE. Conclusions: This systematic review showed no conclusive evidence of any difference between eversion technique and carotid endarterectomy with patch angioplasty in carotid surgery. These conclusions are based on data obtained in trials with very low certainty according to GRADE and should therefore be interpreted cautiously. Until conclusive evidence is obtained, the standard of care according to ESVS guidelines should not be abandoned.

The Average Facial Expressions: A Range of Motion Analysis for Different Sex and Age Groups.

Facial expressions are ubiquitous in communication. Therefore, assessment of mimic function is essential in facial surgery, but no reference standards are currently available. This prospective study aims to create reference values of three-dimensional landmark displacement for different sex and age groups. Methods: Three-dimensional photographs were taken from healthy subjects in rest, maximum closed smile, and pouting. Displacement for both exercises of perioral landmarks was analyzed with MATLAB as absolute displacement and as the ratio of mouth width. Additionally, displacement in three planes was analyzed for each landmark. Averages were calculated for both genders in four age groups: 4-8, 8-12, 12-16, and >16 years. Results: In total, 328 subjects were included. Oral landmarks predominantly moved forward and backward for both exercises. Nasal landmarks predominantly moved vertically. Growing up, oral landmark displacement decreased for smiling, whereas nasal landmark displacement increased. For pouting, oral landmark displacement increased while growing up, whereas nasal landmark displacement decreased. Conclusions: The present study creates reference values for movement of perioral structures for different sex and age groups, for two facial expressions. These data are of great value for the assessment of mimic function and give insight into the development of facial animation over time.

The clinical significance of the human vomeronasal organ.

OBJECTIVE: To find out whether the vomeronasal organ (VNO) can be identified in the nose as a mucosal pit in the anterior nasal septum, to elucidate its function in man and to determine whether it is important to preserve the VNO during septal surgery. METHODS: Literature review. RESULTS AND CONCLUSION: The VNO is histologically present in almost all humans, but a macroscopically visible septal pit does not necessarily correspond with the actual VNO. The human VNO is probably a vestigial organ with a non-operational sensory function. It is not necessary to take particular care not to damage the VNO during septal surgery.

Endoscopic vs. microscopic stapes surgery: An anatomical feasibility study.

Objectives: To investigate the feasibility of the endoscopic approach vs. microscopic approach during stapes surgery, focusing on the visualization of the important anatomical structures of the middle ear, the volume of the resected scutum and chorda tympani (CT) injury. Methods: Fresh frozen human cadaveric heads underwent two stapes surgeries using an operating microscope on one ear and an endoscope on the other ear. The surgeon documented the visualization of critical landmarks, as well as exposure and injury of the CT. The volume of resected scutum was evaluated using cone beam computed tomography scanning and three-dimensional imaging. Results: We performed endoscopic stapes surgery in 10 ears and microscopic stapes surgery in 11 ears. A stapes prosthesis was placed in all ears. The volume of bony scutum resection was significantly lower in the endoscopic group (median = 2.20 mm3, IQR = 4.17) than in the microscopic group (median 13.25 mm3, IQR = 8.71). No scutum was removed in two endoscopic ears, while scutum was removed in all microscopic ears. The endoscopic and microscopic group had similar CT injury. Conclusions: This study showed that the endoscopic stapes surgery procedure is feasible and might be less invasive than microscopic stapes surgery. Future clinical prospective and functional studies will be needed to support our findings.

The origin and course of the infrapatellar branch of the saphenous nerve: An anatomical study.

Nerve injury of the saphenous nerve or infrapatellar branch seems to be a frequent complication following knee surgery or trauma. Denervation results vary, and in some cases, no pain relief is achieved. This might be due to anatomic variation. The purpose of this anatomical study is to identify the variation in the course of the infrapatellar branch and saphenous nerve. We dissected 18 cadavers from adult donors. Medial to the knee, the saphenous nerve and infrapatellar branch were identified and followed proximally to the point where the infrapatellar branch branched from the saphenous nerve. The location where the infrapatellar branch came off from the saphenous nerve relative to the knee joint and where it passed the knee joint were measured. A total of 23 infrapatellar branches were found. We identified 10 branches between 0-10 cm proximal to the knee joint, 3 branches at 10-20 cm, and 9 branches at >20 cm. Between the patella and semitendinosus tendon, the knee joint was crossed by 5 branches in the anterior, 15 in the middle, and 2 in the posterior one-third. The origin of the infrapatellar branch and the location at which it passes the knee are highly variable. This, in addition to people having multiple branches, might explain why denervation is frequently unsuccessful. Based on the anatomical findings, we propose a more proximal diagnostic nerve block to help differentiate between a distal-middle or proximal origin of the infrapatellar branch. Appropriate placement of the nerve block might help identify people who benefit from denervation.

Cochlear implant positioning and fixation using 3D-printed patient specific surgical guides; a cadaveric study.

HYPOTHESIS: To develop and validate the optimal design and evaluate accuracy of individualized 3D- printed surgical guides for cochlear implantation. BACKGROUND: Positioning and fixation of the cochlear implant (CI) are commonly performed free hand. Applications of 3-dimensional (3D) technology now allow us to make patient specific, bone supported surgical guides, to aid CI surgeons with precise placement and drilling out the bony well which accommodates the receiver/stimulator device of the CI. METHODS: Cone beam CT (CBCT) scans were acquired from temporal bones in 9 cadaveric heads (18 ears), followed by virtual planning of the CI position. Surgical, bone-supported drilling guides were designed to conduct a minimally invasive procedure and were 3D-printed. Fixation screws were used to keep the guide in place in predetermined bone areas. Specimens were implanted with 3 different CI models. After implantation, CBCT scans of the implanted specimens were performed. Accuracy of CI placement was assessed by comparing the 3D models of the planned and implanted CI's by calculating the translational and rotational deviations. RESULTS: Median translational deviations of placement in the X- and Y-axis were within the predetermined clinically relevant deviation range (< 3 mm per axis); median translational deviation in the Z-axis was 3.41 mm. Median rotational deviations of placement for X-, Y- and Z-rotation were 5.50°, 4.58° and 3.71°, respectively. CONCLUSION: This study resulted in the first 3D-printed, patient- and CI- model specific surgical guide for positioning during cochlear implantation. The next step for the development and evaluation of this surgical guide will be to evaluate the method in clinical practice.

Multiple Perforations of the ECRB Tendon Using an Innovative Standardized, Reproducible Technique; A Cadaveric Study on Accuracy and Prospective Clinical Safety Assessment Pilot Study. No Adverse Effects in the First 122 Patients with Lateral Epicondylitis.

Background: In LE (Lateral Epicondylitis) otherwise known as Tennis Elbow, the Extensor Carpi Radialis Brevis (ECRB) tendon is most commonly involved. In the majority of studies, injections are performed with a lack of standardization. The Instant Tennis Elbow Cure (ITEC) device has been developed to perform reproducible and standardized perforations by multiple needles. The goal of this pilot study was to estimate the accuracy of this ITEC device by means of a cadaveric study and to assess the clinical safety of this procedure. Methods: Ten cadaveric arms were injected using the ITEC device. The location and depth of the ECRB tendon was measured by ultrasound imaging. The accuracy of the infiltration was assessed by locating the injected dye through dissection and arthrotomy of the cadaveric elbow. A prospective clinical pilot study was conducted to assess the safety of the ITEC device in treating patients with chronic LE. An optional infiltration with an injection fluid was carried out?? Primary outcome measures were side effects and complications of the ITEC device occurring within a follow up period of 8 weeks after treatment. Results: In all cadaveric elbows the injection fluid ( in this case an injection fluid) was located at the ECRB tendon. In one cadaver, a minimal amount of dye was found intra-articular and in 3 cadavers a small quantity was located in the surrounding tissue of the ECRB tendon. 122 patients with LE were treated with the ITEC device. No adverse effects or complications were reported at 8-week follow up. Conclusion: Treatment of LE using the ITEC device appears accurate and safe. It may improve future research since it is reproducible and it can be performed in a standardized way.

Identification of the Peri-oral Mimic Muscles on Cadaver Slices and 3 and 7 Tesla MRI Scans.

Decreased smile dynamics is reported as an unwanted side effect after Le Fort I osteotomies. It is assumed that this negative sequela might be caused by postoperative changes in the anatomy of peri-oral mimic muscles. Due to a lack of specific anatomical knowledge, the exact mechanism is not yet clarified. This makes prevention of the undesired changes in smile dynamics difficult. The first aim of this study is to increase basic anatomical and radiological MRI knowledge of the peri-oral mimic muscles. The second aim is to investigate if 7 Tesla MRI scans are better suited to identify these muscles than 3 Tesla MRI scans. METHODS: Eleven peri-oral mimic muscles were chosen as subjects of the present study. Three and 7 Tesla MRI scans of a cadaver head were made. The same head was cut in axial slices using a cryomacrotome. Every second slice was digitally photographed. A three-dimensional model was created utilizing EMAC software, which served as gold standard for the identification and comparison of the chosen peri-oral mimic muscles on both MRI scans. RESULTS: All predetermined peri-oral mimic muscles could be identified in the cadaver head, and a detailed radiological atlas was created. The ease of identification and separation of the peri-oral mimic muscles was significantly higher on the 7 Tesla MRI than on the 3 Tesla MRI scan (P < 0.001). CONCLUSION: A 7 Tesla MRI scanner offers great improvement in the identification of peri-oral mimic muscles compared with a 3 Tesla scanner.

The Presence of Metastatic Thoracic Duct Lymph Nodes in Western Esophageal Cancer Patients: A Multinational Observational Study.

BACKGROUND: The thoracic lymphadenectomy during an esophagectomy for esophageal cancer includes resection of the thoracic duct (TD) compartment containing the TD lymph nodes (TDLNs). The role of TD compartment resection is still a topic of debate since metastatic TDLNs have only been demonstrated in squamous cell carcinomas in Eastern esophageal cancer patients. Therefore, the aim of this study was to assess the presence and metastatic involvement of TDLNs in a Western population, in which adenocarcinoma is the predominant type of esophageal cancer. METHODS: From July 2017 to May 2020, all consecutive patients undergoing an open or robot-assisted transthoracic esophagectomy with concurrent lymphadenectomy and resection of the TD compartment in the University Medical Center Utrecht in Utrecht, the Netherlands, and the Città della Salute e della Scienza University Hospital in Turin, Italy, were included. The TD compartment was resected en bloc and was separated in the operation room by the operating surgeon after which it was macroscopically and microscopically assessed for (metastatic) TDLNs by the pathologist. RESULTS: A total of 117 patients with an adenocarcinoma (73%) or squamous cell carcinoma (27%) of the esophagus were included. In 61 (52%) patients, TDLNs were found, containing metastasis in 9 (15%) patients. No major complications related to TD compartment resection were observed. CONCLUSIONS: This study demonstrates the presence of metastatic TDLNs in adenocarcinomas of the esophagus. This result provides a valid argument to routinely extend the thoracic lymphadenectomy with resection of the TD compartment during an esophagectomy for esophageal cancer.

A comparative anatomical and histological study on the presence of an apical splenic nerve in mice and humans.

The cranial pole of the mouse spleen is considered to be parasympathetically innervated by a macroscopic observable nerve referred to as the apical splenic nerve (ASN). Electrical stimulation of the ASN resulted in increased levels of splenic acetylcholine, decreased lipopolysaccharide-induced levels of systemic tumor necrosis factor alpha and mitigated clinical symptoms in a mouse model of rheumatoid arthritis. If such a discrete ASN would be present in humans, this structure is of interest as it might represent a relatively easily accessible electrical stimulation target to treat immune-mediated inflammatory diseases. So far, it is unknown if a human ASN equivalent exists. This study aimed to provide a detailed description of the location and course of the ASN in mice. Subsequently, this information was used for a guided exploration of an equivalent structure in humans. Microscopic techniques were applied to confirm nerve identity and compare ASN composition. Six mice and six human cadavers were used to study and compare the ASN, both macro- and microscopically. Macroscopic morphological characteristics of the ASN in both mice and humans were described and photographs were taken. ASN samples were resected, embedded in paraffin, cut in 5 µm thin sections where after adjacent sections were stained with a general, sympathetic and parasympathetic nerve marker, respectively. Neural identity and nerve fiber composition was then evaluated microscopically. Macroscopically, the ASN could be clearly identified in all mice and was running in the phrenicosplenic ligament connecting the diaphragm and apical pole of the spleen. If a phrenicosplenic ligament was present in humans, a similar configuration of potential neural structures was observed. Since the gastrosplenic ligament was a continuation of the phrenicosplenic ligament, this ligament was explored as well and contained white, potential discrete nerve-like structures as well which could represent an ANS equivalent. Microscopic evaluation of the ASN in mice and human showed that this structure did not represent a nerve, but most likely connective tissue strains. White nerve-like structures, which could represent the ASN, were macroscopically observed in the phrenicosplenic ligament in both mice and human and in the gastrosplenic ligament in humans. The microscopic investigation did not confirm their neural identity and therefore, this study disclaims the existence of a parasympathetic ASN in both mice and human.

Microanatomy of the Frontal Branch of the Facial Nerve: The Role of Nerve Caliber and Axonal Capacity.

BACKGROUND: A commonly seen issue in facial palsy patients is brow ptosis caused by paralysis of the frontalis muscle powered by the frontal branch of the facial nerve. Predominantly, static methods are used for correction. Functional restoration concepts include the transfer of the deep temporal branch of the trigeminal nerve and cross-facial nerve grafts. Both techniques can neurotize the original mimic muscles in early cases or power muscle transplants in late cases. Because axonal capacity is particularly important in cross-facial nerve graft procedures, the authors investigated the microanatomical features of the frontal branch to provide the basis for its potential use and to ease intraoperative donor nerve selection. METHODS: Nerve biopsy specimens from 106 fresh-frozen cadaver facial halves were obtained. Histologic processing and digitalization were followed by nerve morphometric analysis and semiautomated axon quantification. RESULTS: The frontal branch showed a median of three fascicles (n = 100; range, one to nine fascicles). A mean axonal capacity of 1191 ± 668 axons (range, 186 to 3539 axons; n = 88) and an average cross-sectional diameter of 1.01 ± 0.26 mm (range, 0.43 to 1.74 mm; n = 67) were noted. In the linear regression model, diameter and axonal capacity demonstrated a positive relation (n = 57; r2 = 0.32; p < 0.001). Based on that equation, a nerve measuring 1 mm is expected to carry 1339 axons. CONCLUSION: The authors' analysis on the microanatomy of the frontal branch could promote clinical use of cross-facial nerve graft procedures in frontalis muscle neurotization and free muscle transplantations.

Surgical anatomy of the upper esophagus related to robot-assisted cervical esophagectomy.

Robot-assisted cervical esophagectomy (RACE) enables radical surgery for tumors of the middle and upper esophagus, avoiding a transthoracic approach. However, the cervical access, narrow working space, and complex topographic anatomy make this procedure particularly demanding. Our study offers a stepwise description of appropriate dissection planes and anatomical landmarks to facilitate RACE. Macroscopic dissections were performed on formaldehyde-fixed body donors (three females, three males), according to the surgical steps during RACE. The topographic anatomy and surgically relevant structures related to the cervical access route to the esophagus were described and illustrated, along with the complete mobilization of the cervical and upper thoracic segment. The carotid sheath, intercarotid fascia, and visceral fascia were identified as helpful landmarks, used as optimal dissection planes to approach the cervical esophagus and preserve the structures at risk (trachea, recurrent laryngeal nerves, thoracic duct, sympathetic trunk). While ventral dissection involved detachment of the esophagus from the tracheal cartilage and membranous part, the dorsal dissection plane comprised the prevertebral compartment harboring the thoracic duct and right intercosto-bronchial artery. On the left side, the esophagus was attached to the aortic arch by the aorto-esophageal ligament; on the right side, the esophagus was bordered by the azygos vein, right vagus nerve, and cardiac nerves. The stepwise, illustrated topographic anatomy addressed specific surgical demands and perspectives related to the left cervical approach and dissection of the esophagus, providing an anatomical basis to facilitate and safely implement the RACE procedure.

Histopathological characterization of intimal lesions and arterial wall calcification in the arteries of the leg of elderly cadavers.

INTRODUCTION: Although arteries of the leg have been studied in extensively diseased amputation specimens, little is known about the composition of vascular lesions present in the general population. The aim of this study was to describe the natural development of adaptive intimal thickening, atherosclerotic lesion development and vascular calcification in the leg of a general elderly population. MATERIALS AND METHODS: Two hundred and seventy postmortem samples from the popliteal and posterior tibial arteries of 14 elderly cadavers were studied histologically. RESULTS: Atherosclerotic lesions were more frequently observed in the popliteal (60%) than in the posterior tibial artery (34%; p < .0005). These atherosclerotic plaques were most often nonatheromatous (80% and 83% for popliteal and posterior tibial plaques, respectively). The atheroma's that were present were small (most <25% of plaque area). Atherosclerotic plaque calcification was observed more often in the popliteal (39%) than in the posterior tibial samples (17%; p < .0005). Medial arterial calcification was observed more often in the posterior tibial (62%) than in the popliteal samples (46%; p = .008). Plaque calcification and medial arterial calcification were not associated with lumen stenosis. CONCLUSIONS: In the leg of elderly cadavers, the presence of atherosclerotic plaque and intimal calcification decreases from the proximal popliteal artery to the more distal posterior tibial artery and most atherosclerotic lesions are of the fibrous nonatheromatous type. In contrast, the presence and severity of medial calcification increases from proximal to distal.

Feasibility of fresh frozen human cadavers as a research and training model for endovascular image guided interventions.

OBJECTIVE: To describe the feasibility of a fresh frozen human cadaver model for research and training of endovascular image guided procedures in the aorta and lower extremity. METHODS: The cadaver model was constructed in fresh frozen human cadaver torsos and lower extremities. Endovascular access was acquired by inserting a sheath in the femoral artery. The arterial segment of the specimen was restricted by ligation of collateral arteries and, in the torsos, clamping of the contralateral femoral artery and balloon occlusion of the supratruncal aorta. Tap water was administered through the sheath to create sufficient intraluminal pressure to manipulate devices and acquire digital subtraction angiography (DSA). Endovascular cannulation tasks of the visceral arteries (torso) or the peripheral arteries (lower extremities) were performed to assess the vascular patency of the model. Feasibility of this model is based on our institute's experiences throughout the use of six fresh frozen human cadaver torsos and 22 lower extremities. RESULTS: Endovascular simulation in the aortic and peripheral vasculature was achieved using this human cadaver model. Acquisition of DSA images was feasible in both the torsos and the lower extremities. Approximately 84 of the 90 target vessels (93.3%) were patent, the remaining six vessels showed signs of calcified steno-occlusive disease. CONCLUSIONS: Fresh frozen human cadavers provide a feasible simulation model for aortic and peripheral endovascular interventions, and can potentially reduce the need for animal experimentation. This model is suitable for the evaluation of new endovascular devices and techniques or to master endovascular skills.

Morphological hallmarks facilitating distinction of omental milky spots and lymph nodes: an exploratory study on their discriminative capacity.

BACKGROUND: Omental milky spots (OMSs) are the primary lymphoid structures of the greater omentum. However, the presence of lymph nodes (LNs) has occasionally been mentioned as well. Understanding which lymphoid structures are present is of significance, especially in gastric tumor metastasis; tumor deposits in omental LNs suggest local lymphatic spread, whereas tumor deposits in OMSs suggest peritoneal spread and hence extensive disease. Since LNs and OMSs share morphological characteristics and OMSs might be wrongly identified as LNs, reliable hallmarks facilitating easy discrimination are needed. MATERIALS AND METHOD: A series of microscopic morphological hallmarks unique to LNs were selected as potential candidates and were assessed for their discriminative capacity: 1) capsule, 2) trabeculae, 3) subcapsular sinus, 4) afferent lymphatic vessels, 5) distinct B- and T cell regions, and 6) a layered organization with, from the outside in a capsule, cortex, paracortex, and medulla. These hallmarks were visualized by multiple staining techniques. RESULTS: Hallmarks 1, 2 5 and 6 were shown to be the most efficient as these were consistent and discriminative. They were best visualized by Picrosirius red, smooth muscle actin and a B-cell / T-cell double staining. CONCLUSION: The presence of a capsule, trabeculae, distinct B- and T-cell regions and a layered organization represent consistent and reliable morphological features which allow to easily distinguish LNs from OMSs, especially when applied in combination.

Eversion technique versus conventional endarterectomy with patch angioplasty in carotid surgery: protocol for a systematic review with meta-analyses and trial sequential analysis of randomised clinical trials.

INTRODUCTION: Traditional carotid endarterectomy is considered to be the standard technique for prevention of a new stroke in patients with a symptomatic carotid stenosis. Use of patch angioplasty to restore the arterial wall after longitudinal endarterectomy is, to date, not unequivocally proven to be superior to eversion technique. A systematic review is needed for evaluation of benefits and harms of the eversion technique versus the traditional endarterectomy with patch angioplasty in patients with symptomatic carotid stenosis. METHODS AND OUTCOMES: The review will be conducted according to this protocol following the recommendations of the 'Cochrane Handbook for Systematic Reviews' and reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Randomised clinical trials comparing eversion technique versus endarterectomy with patch angioplasty in patients with a symptomatic stenosis of the internal carotid artery will be included. Primary outcomes are all-cause mortality rate, health-related quality of life and serious adverse events. Secondary outcomes are 30-day stroke and mortality rate, symptomatic arterial restenosis or occlusion and non-serious adverse events. The databases Cochrane Central Register of Controlled Trials, PubMed/MEDLINE and EMBASE will be searched (November 2019). We will primarily base our conclusions on meta-analyses of trials with overall low-risk of bias. We will use trial sequential analysis to assist the evaluation of imprecision in Grading of Recommendations, Assessment, Development and Evaluation. However, if pooled point estimates of all trials are similar to pooled point estimates of trials with overall low risk of bias and there is lack of a statistical significant interaction between estimates from trials with overall high risk of bias and trials with overall low risk of bias we will consider the trial sequential analysis adjusted precision of the estimate achieved in all trials as the result of our meta-analyses. ETHICS AND DISSEMINATION: The proposed systematic review will collect and analyse data from published studies, therefore, ethical approval is not required. The results of the review will be disseminated by publication in a peer-review journal and submitted for presentation at conferences. PROSPERO REGISTRATION NUMBER: CRD42019119361.

Sympathetic nerve tissue in milky spots of the human greater omentum.

Omental milky spots (OMSs), small lymphoid structures positioned in the greater omentum, are involved in peritoneal immune homeostasis and the formation of omental metastases. Sympathetic nerve activity is known to regulate immune function in other lymphoid organs (e.g. spleen and lymph nodes) and to create a favourable microenvironment for various tumour types. However, it is still unknown whether OMSs receive sympathetic innervation. Therefore, the aim of this study was to establish whether OMSs of the adult human greater omentum receive sympathetic innervation. A total of 18 OMSs were isolated from five omenta, which were removed from 3% formaldehyde-perfused cadavers (with a median age of 84 years, ranging from 64 to 94). OMSs were embedded in paraffin, cut and stained with a general (PGP9.5) and sympathetic nerve marker (TH and DBH), and evaluated by bright field microscopy. A T-cell, B-cell, and macrophage staining was performed to confirm OMS identity. In 50% of the studied OMSs, sympathetic nerve fibres were observed at multiple levels of the same OMS. Nerve fibres were represented as dots or elongated structures and often observed in relation to small vessels and occasionally as individual structures residing between lymphoid cells. The current study shows that 50% of the investigated OMSs contain sympathetic nerve fibres. These findings may contribute to our understanding of neural regulation of peritoneal immune response and the involvement of OMSs in omental metastases.