Initial evaluation and external validation of 68Ga-PSMA-11 PET/CT in tubarial gland characterization

INTRODUCTION

Radiotracer 68Ga-PSMA-11 used in PET/CT scans allows for identification and localization of gland tissue. It allows for their consideration in clinical scenarios and to design further and stronger research to answer pertinent questions regarding their function and implications. We aimed to externally validate first reported findings of location, size, and ligand uptake of the tubarial glands using 68Ga-PSMA-11 PET/CT.

MATERIALS AND METHODS

A cross-sectional study was performed with 68Ga-PSMA-11 PET/CT studies of patients with prostate cancer confirmed diagnosis from the database of the Radiology Department from 2018 to 2022. The maximum cephalocaudal length (CCL) in the tubarial glands and the Maximum Standardized Uptake Value (SUVmax) of major glands were recorded.

RESULTS

A total of 202 patients were included (mean age 67.43 ± 8.5). The mean CCL of the tubarial glands was 37.38 ± 9.84 and a SUVmax of 6.56 ± 2.14. The rest of the glands were as follows: parotid 15.12 ± 4.43, submandibular 16.82 ± 5.43 and sublingual 5.84 ± 3.24. No differences were found between laterality. A weak correlation between age and SUVmax of tubarial glands was identified. Tubarial glands had a similar 68Ga-PSMA-11 uptake to that of sublingual glands.

CONCLUSION

This study corroborates the existence of a conglomerate of glands in the nasopharynx roof, near the posterolateral pharyngeal recess. It serves as validation in a different population with similar results in previous research. Without 68GA-PSMA-11 PET/CT the abundance, configuration and potential clinical relevance of these glands would probably not have been identified. Radiotracer uptake was similar amongst the major salivary glands, with a more similar uptake to that shown by the sublingual gland.

Screws versus plate with screws for osteosynthesis of the posterior malleolus: a systematic review and meta-analysis

INTRODUCTION

fractures involving the posterior malleolus (PM) of the ankle can have significant functional and clinical implications if not properly treated. The optimal treatment approach for these fractures remains uncertain. This review aims to compare the use of cannulated screws versus plate with screw fixation in terms of their impact on the development of postoperative ankle osteoarthritis and functional outcomes in patients with PM fractures.

MATERIAL AND METHODS

a comprehensive search was conducted in PubMed, EMBASE, and Cochrane Library databases to identify studies directly comparing cannulated screws versus plate with screw fixation for PM fractures and their association with the development of postoperative osteoarthritis and functional outcomes. The quality of the included studies was assessed using appropriate assessment tools. The data on osteoarthritis development and functional outcomes were extracted and analyzed.

RESULTS

a total of 691 articles were screened, and several studies were included for analysis. The findings revealed no statistically significant difference in the development of postoperative ankle osteoarthritis between the cannulated screws and plate with screw fixation groups. Similarly, there was no significant difference in functional outcomes between the two treatment approaches.

CONCLUSION

based on the available evidence, there is no significant difference in the development of postoperative ankle osteoarthritis or functional outcomes between cannulated screws and plate with screw fixation for PM fractures. However, further research is needed to strengthen these findings and provide more conclusive evidence.

Gallstone Ileus in a Young Patient: A Clinical Case Report and Literature Review

Gallstone ileus is a rare presentation of gallbladder disease. It is mostly encountered in female and elderly patients. It occurs when a stone causes a fistula between the gallbladder and the intestinal lumen. More than half of the patients do not have a history of biliary disease. Surgical intervention is still considered the best treatment option; however, the best choice between one-stage and two-stage surgery is still unknown. We present a gallstone Ileus case in a patient with uncommon epidemiological characteristics: a 28-year-old male Hispanic patient without a gallbladder disease history.

Fixed-bearing unicompartmental knee arthroplasty provides a lower failure rate than mobile-bearing unicompartimental knee arthroplasty when used after a failed high tibial osteotomy: a systematic review and meta-analysis

Despite the fact that the choice of bearing design has been thought to influence the functional outcomes and longevity of unicompartimental knee arthroplasty (UKA), there is a lack of clinical evidence supporting the decision-making process in patients who have undergone high tibial osteotomy (HTO). A systematic review of studies was carried out that reported the outcomes of fixed-bearing (FB) or mobile-bearing (MB) medial UKA in patients with a previous HTO. A random effect meta-analysis using a generalized linear mixed-effects model to calculate revision rates was done. Seven retrospective cohort studies were included for this study. Regarding the fixation method, 40 were the FB-UKA and 47 were MB-UKA. For both groups, the mean post-operative follow-up was 5.8 years. The survival rates were 92% for the FB-UKA with a mean follow-up of 10 years. For the MB-UKA, it ranged from 35.7 to 93%, with a mean follow-up of 4.2 years. For the FB, the time to revision was reported as 9.3 years, while 1.2, 2.5 and 2.91 years was reported for the MB. The results of the meta-analysis showed that the revision rate for the patients receiving a FB-UKA after failed HTO was 8%, compared to 17% in those who received an MB-UKA. The results of the review suggest that the use of the FB-UKA is associated with lower revision rates and a longer survival time than the MB-UKA and have similar functional ability scores.Level of evidence: III (systematic review of level-III studies).

Staph’s Toxins IgE Antibodies and Its Relation to the Severity of Allergic Rhinitis

Background

Specific IgE against Staphylococcus can be found in approximately 40% of patients with allergies, also in patients without allergies because they may be sensitized. These antibodies are functional, and they can induce histamine release contributing to chronic pruritus which can worsen disease severity. The objective of this study was to compare levels of specific IgE against S. aureus toxins in those populations.

Methods

A cross-sectional, comparative non-blinded survey was made at the Regional Center for Allergy and Clinical Immunology. Ninety-nine adults between 18 and 70 years of age with allergic rhinitis (AR) and without allergic rhinitis (wAR) were recruited. A clinical history and demographic data, and allergic sensitization patterns to 35 aeroallergens were obtained, and participants were classified according to their severity using the Allergic Rhinitis and Its Impact on Asthma (ARIA) classification. Specific IgE levels were determined using ImmunoCAP™ 100 platform.

Results

The median age (IQR) of the participants was 23 (20–33.7); 56.2% were women. The most frequent comorbidities were asthma and obesity. Of the patients with AR, 46.7% were classified as mild intermittent and 25% as moderate persistent. IgE levels against staph toxins A, B, and TSST were significantly higher in the AR group vs the wAR group [median IQR 0.01 (0.01–0.03) vs. 0.01 (0–0.02), p = 0.01; 0.02 (0.01–0.03) vs. 0.01 (0–0.02), p= 0.02; 0.04 (0.02–0.09) vs. 0.01 (0–0.04), p=0.002, respectably]. A significant difference was found in serum IgE levels against Staph B toxin between severity subgroups.

Conclusion

People with AR have higher IgE levels against staph toxins A, B and TSST than wAR subjects. However, it is not possible declare that the IgE titers were related to disease severity.

MRI evaluation of the peripheral attachments of the lateral meniscal body: the menisco-tibio-popliteus-fibular complex

PURPOSE

To determine, identify and measure the structures of the menisco-tibio-popliteus-fibular complex (MTPFC) with magnetic resonance imaging (MRI) in knees without structural abnormalities or a history of knee surgery.

METHODS

One-hundred-and-five knees without prior injury or antecedent surgery were analyzed by means of MRI. The average age was 50.1 years ± 14.8. All the measurements were performed by three observers. The peripherical structures of the lateral meniscus body were identified to determine the location, size, and thickness of the entire MTPFC. The distance to other "key areas" in the lateral compartment was also studied and compared by gender and age.

RESULTS

The lateral meniscotibial ligament (LMTL) was found in 97.1% of the MRIs, the popliteofibular ligament (PFL) in 93.3%, the popliteomeniscal ligaments (PML) in 90.4% and the meniscofibular ligament (MFL) in 39%. The anteroposterior distance of the LMTL in an axial view was 20.7 mm ± 3.9, the anterior thickness of the LMTL was 1.1 mm ± 0.3, and the posterior thickness of the LMTL 1.2 mm ± 0.1 and the height in a coronal view was 10.8 mm ± 1.9. The length of the PFL in a coronal view was 8.7 mm ± 2.5, the thickness was 1.4 mm ± 0.4 and the width in an axial view was 7.8 mm ± 2.2.

CONCLUSIONS

The MTPFC has a constant morphological and anatomical pattern for three of its main ligaments and can be easily identified and measured in an MRI; the MFL has a lower prevalence, considering a structure difficult to identify by 1.5 T MRI.

Factors Influencing Scientific Achievements of Medical Students in the Anatomy Research Group: An Analysis From the Autonomous University of Nuevo León in Mexico

Scientific research and student involvement are critical to the formation of physicians, yet the number of medical researchers has decreased over time. To implement corrective strategies, the variables associated with positive research attitudes and productivity among medical students must be identified. The aim of this study was to evaluate the variables associated with students interested or involved in research. A validated questionnaire was applied to the student members of an established anatomy research group in a Mexican medical school with a six-year medical program. Data were collected and analyzed. A total of 85.5% (n = 77/90) students answered the survey with most respondents being second-year medical students. The majority of respondents indicated that the important component of conducting research was a contribution to the new knowledge (45.5%) and to the scientific community (42.9%). More than half of respondents mentioned a professor or a peer as the initial motivation to become involved in research. Lack of time was the main limitation (59.7%) to research involvement. Perceived benefits were knowledge and team work skills. Of those involved, most (85.7%) wished to continue participating in research as a complement to their clinical work. Professors and student colleagues were found to play an important motivational and recruitment role for medical research. These efforts in turn have developed into long-lasting mentor-mentee relationships. Students also anticipated that early involvement in research will positively influence the likelihood of future physicians' contribution and collaboration in research.

The morphology of the femoral footprint of the anterior cruciate ligament changes with aging from a large semicircular shape to a small flat ribbon-like shape

PURPOSE

Compare the differences in the morphology of the ACL femoral footprint between the cadavers of the young and elderly in consideration of the degenerative physiological process that occurs with aging.

METHODS

The femoral footprint of the ACL was dissected in 81 knees of known gender and age (45 male/36 female). They were divided into four groups by age and gender, establishing 50 years as the cut-off point to divide patients by age. Three observers analyzed the femoral footprint dissections, and the shapes were described and classified. The area and morphometric characteristics of the femoral insertion of the ACL were determined and these were compared between genders and age groups.

RESULTS

The femoral footprint of the ACL from the cadavers of males younger than 50 years of age presented a semicircular morphology in 90% of the cases. In males aged more than 50 years, a ribbon-like morphology was found in 96% of the cases. In women less than 50 years old, the semicircular morphology was observed in 93.7% of the cases. In women aged over 50 years old, the ribbon-like morphology was found in 95% of the cases. A significant difference was observed between the prevalence rates of the morphologies, area size and measurements of the younger and older groups (p < 0.001 for both genders).

CONCLUSIONS

The femoral insertion of the ACL presents variations in its morphology, area and morphometric characteristics over time. It goes from a large semicircular shape that almost contacts the posterior articular cartilage to a smaller, flattened ribbon-like shape that moves away from the edge of the articular cartilage. It is bounded anteriorly by the lateral intercondylar ridge. These findings should be considered to avoid employing reconstruction techniques in which femoral tunnels with oval or rectangular shapes are used in patients under 50 years of age because they do not correspond to the morphology of the femoral insertion of the ACL in this age group.

Aged rats learn Morris Water maze using non-spatial search strategies evidenced by a parameter-based algorithm

Spatial learning and memory are used by all individuals who need to move in a space. Morris water maze (MWM) is an accepted method for its evaluation in murine models and has many protocols, ranging from the classic parameters of latency, distance, and number of crossings to the platform zone, to other more complex methods involving computerized trajectory analysis. Algorithm-based SS analysis is an alternative that enriches traditional classic parameters. We developed a non-computerized parameter-based Search Strategy Algorithm (SSA), to classify strategies and detect changes in spatial memory and learning. For this, our algorithm was validated using young and aged rats, evaluated by two observers who classified the trajectories of the rats based on the effectiveness, localization, and precision to reach the platform. SSA is classified into 10 categories, classified by effectiveness, initial direction, and precision. Traditional measurements were unable to show significant differences in the learning process. However, significant differences were identified in SSA. Young rats used a direct search strategy (SS), while aged rats preferred indirect ones. The number of platform crossings was the only variable to show the difference in the intermediate probe trial. The parameter-based algorithm represents an alternative to the computerized SS methods to analyze the spatial memory and learning process in young and age rats. We validate the use of SSA as an alternative to computerized SS analysis spatial learning acquisition. We demonstrated that aged rats had the ability to learn spatial memory tasks using different search strategies. The use of SSA resulted in a reliable and reproducible method to analyze MWM protocols.

Relationship of Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratio With Visual Acuity After Surgical Repair of Open Globe Injury

Purpose: To assess the relationship and prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) with poor final best-corrected visual acuity (BCVA) after surgical repair of open globe injuries (OGI) in adults.

Design: Retrospective analysis of data from an ongoing prospective cohort of consecutive patients.

Methods: In a tertiary university hospital, 197 eyes of 197 patients were included between 2013 and 2017. NLR and PLR were obtained from pre-operative blood tests to analyze its relationship with poor final BCVA.

Results: Severe visual impairment (SVI) was defined as ≤20/200, and was observed in 96 (48.7%) patients after surgical repair of OGI. SVI patients had higher NLR (7.4 ± 6.6 vs. 4.0 ± 3.2, p < 0.001), and PLR (167 ± 92 vs. 139 ± 64; p = 0.021) than non-SVI. NLR ≥ 3.47 and PLR ≥ 112.2 were the best cut-off values for SVI, were univariate risk factors for SVI, and had sensitivity: 69.0, 71.4, and specificity: 63.6, 44.8, respectively. In multivariate analysis, only OTS, athalamia, and hyphema remained as risk factors. NLR had significant correlation with ocular trauma score (OTS) (r = −0.389, p < 0.001) and final BCVA (r = 0.345, p < 0.001).

Limitations: Simultaneous trauma in other parts of the body that could influence the laboratory findings.

Conclusion: Patients with SVI after a repaired OGI had increased pre-operative NLR and PLR levels. High NLR and PLR are risk factors for SVI in univariate analysis. It is confirmed that low OTS is a risk factor for SVI. High NLR and PLR could be used as a prognostic tool to identify patients at higher risk for SVI after repair of OGI.

Localized gallbladder perforation: a systematic review of treatment and prognosis

BACKGROUND

The optimal management of localized gallbladder perforation (Neimeier type II) has yet to be defined. The aim of this systematic review was to identify factors associated with improved patient outcomes.

METHODS

Systematic review of studies that described the management of Neimeier type II perforation, reported complications of the first intervention, necessity of added interventions, resolution of the pathology, and days of hospital stay were included. The search strategy was conducted in EMBASE, Mayo Journals, MEDLINE, SCOPUS, and Web of Science (December 2020) RESULTS: A total of 122 patients (53% male) from case reports, series, and cohorts were included for analysis. In total 56 (46%) and 44 (36%)patients were treated with open and laparoscopic cholecystectomy respectively. Overall risk of bias was moderate. The need for another intervention was higher in the laparoscopic group (5 vs 17, p=<0.001) as well as prevalence of complications (4 vs 16, p=<0.001), but lower for days of hospital stay (median days 5. vs 15, p = 0.008) against open cholecystectomy. Preoperative percutaneous catheter drainage did not influence outcome.

CONCLUSION

Open cholecystectomy has a lower need for further surgical procedures and postoperative complications, but a longer hospital stay. These outcomes did not vary with preoperative percutaneous drainage. The effect of timing of cholecystectomy did not influence the outcomes.

Proteomic profile of preeclampsia in the first trimester of pregnancy

OBJECTIVE

Preeclampsia (PE) is a leading cause of pregnancy-associated maternal and neonatal morbidity and mortality. Detection of patients at risk before the clinical onset of PE is a priority. Proteomics have become a valuable tool for the discovery of new biomarkers; however, the understanding of the underlying mechanism is necessary. The aim of the study was to determine differences between proteomic serum profiles of PE and normotensive pregnancies using quantitative and qualitative approaches.

STUDY DESIGN

Serum samples from pregnant women were taken at 10-12 weeks of gestation with follow-up to determine PE development. Samples were analyzed using nano 2-D liquid chromatography UPLC and qTOF-MS/MS.

RESULTS

A total of 136 women were recruited, of which eight (5.9%) developed PE, and eight normotensive were randomly selected as a control group for comparison. A different profile was obtained between groups. Nine proteins showed quantitative differences with fold-change over 1.5: PRRC2C (217.02), HEATR5A (179.46), ATP6 (162.38), PRRC2B (83.09), RBM25 (5.36), NUP205 (3.38), HLA-I (2.27), ZC3H13 (2.15), and SREK1 (1.66); and two under 0.66: Importin-4 (0.55) and Cytochrome b (0.26). Using bilateral Fisher's exact test for the qualitative approach, LRRK1 had statistical significance (p = .044), while PRRC2B (p = .121), PRRC2C (p = .134), and NUP205 (p = .134) showed a tendency to be present in PE.

CONCLUSION

The found proteins have plausibility with the early pathophysiological events that have been associated with this pathology. Further studies should be performed to confirm these findings and elucidate their specific roles.

Avoiding iatrogenic injuries to the vertebral artery: A morphometric study of the vertebral artery-free dissection area

OBJECTIVE

To determine the area of a safety window that excludes the vertebral artery for the safe access of the occipital condyle screws during occipitocervical fixation.

METHODS

This study included 138 cervical computed tomography angiograms. Six measurements per side were made in each imaging study. These measurements are from the vertebral artery to (A) the mastoid process, (B) the mastoid incisura, (C) the posterior condylar fossa, (D) the occipital condyle in its midline, and (E) the medial border of the condyle. We also measured from the tip of the mastoid process to the lower border of the occipital condyle on its lateral side (F).

RESULTS

A total of 276 areas from 138 individuals were included, of which 51.4 % were men. The mean age was 54.2 ± 18.63 years. The mean variable measurements (mm) for all the population were 21 ± 4, 16 ± 3, 6 ± 2, 3 ± 2, 2 ± 1 and 35 ± 4 for variables A-F, respectively. We found significant differences between sex when we compared measurements A (p = 0.003), C (p = 0.001), D (p = 0.000) and F (p = 0.000). The incidence rate of dominance for the vertebral artery was 18.8 % and 30.4 % for right and left respectively.

CONCLUSION

Women had significantly smaller measures than men. This could indicate a higher risk of iatrogenic injury secondary to a smaller vertebral artery-free area. Results may guide surgeons in the pre-surgical planning aiming to reduce the risk of iatrogenic injuries to the vertebral artery.

Origin variations of the superior thyroid, lingual, and facial arteries: a computed tomography angiography study

PURPOSE

To determine the anatomical variations and morphology of the external carotid artery (ECA) and its anterior branches.

METHODS

Using computed tomography angiography (CTA), the origin, internal diameter, and surface laterality emergence of the superior thyroid (STA), lingual (LA), and facial (FA) arteries were evaluated retrospectively evaluated and classified. The bifurcation level of the common carotid artery (CCA) in relation to the cervical vertebrae and disc was also determined.

RESULTS

A total of 76 CTA were included in the study. STA originated from the carotid bifurcation (CB) (type I), CCA (type II) and ECA (type III) in 20.4 (31/152), 17.1 (26/152) and 50.7% (77/152) cases, respectively. Also 10.5% (16/152) arose from a shared trunk with LA as a thyrolingual trunk (TLT) (type IVa), and absent in 1.3% (2/152). LA originated in the CB in only one case. A linguofacial trunk (LFT) was present in 14.5% (22/152). Mean diameters of STA, LA and FA were 1.70, 1.95 and 2.45 mm, respectively. Meanwhile, surface laterality were predominately from anteromedial, medial, and anterior, respectively. CB was mainly on C3 or C3-C4 (55.9% of cases).

CONCLUSIONS

STA origin below the ECA is a common finding. Our population presented the highest percentage of TLT (10.5%) and high CB (9.8%) in literature. Considering these variations are important to prevent complications in neck surgical procedures.

A proposed extension to the elongated styloid process definition: A morphological study with high-resolution tomography computer

The objective of the present study was to evaluate the morphology and angulation of the styloid process (SP), analyzing results stratified by gender, side and age on asymptomatic patients. We retrospectively analyzed 99 high-resolution computed tomography study images from asymptomatic patients. The images were assessed intra-observatory by a head and neck expert radiologist. Data for length, morphology, and angulation in a coronal and sagittal plane were recorded and stratified by age and gender. Morphology was classified according to the Langlais modified by Guimares classification. The mean lengths were 31.67±0.97mm and 31.64±0.90mm for the right and left sides respectively. Using the Langlais modified by Guimares classification, the normal type was the most prevalent and without a statistically significant difference when comparing between genders. A total of 27.6% presented a morphologically elongated SP (>25mm of continuous process), 49.5% presented a radiologically elongated SP (>30mm), and a total of 9.59% had a longer length than the proposed≤45mm. The right transverse angle was greater in men than women, and a statistically significant difference was found (P=0.010). We show the morphological variability of the SP. Although our results are reported with the traditional definition, the high prevalence supports the need for a new definition of elongated SP and a normal angulation ranges.

The Use of Clinical Reasoning Skills in the Setting of Uncertainty: A Case of Trial Femoral Head Migration

Clinical skills and medical knowledge enable physicians to overcome the uncertainty of emergent and rare clinical scenarios. Recently, a growing emphasis on evidence-based medicine (EBM) has flooded medical curricula of universities across the globe with guideline-based material, and while it has given teachers and students new tools to improve medical education, clinical reasoning must be reaffirmed in its capacity to provide physicians with the ability to solve unexpected clinical scenarios. Anatomical education in medical school should have two main objectives: to acquire anatomical knowledge and to develop the skill of applying that knowledge in clinical scenarios. The authors present a clinical scenario in which an unexpected and rare complication occurred during a routine elective hip replacement surgery. The general surgeon presiding over the case, also an anatomy professor, solved the problem using clinical reasoning and anatomical knowledge. It was a clear example of how clinical reasoning is key in approaching unprecedented, rare, or unknown complications. The intention of this scenario is to remind colleagues and medical schools that, although EBM is the standard, educators must uphold sound clinical reasoning to best prepare health care providers for their careers.

Uncommon variant of pre-axial polydactyly and its surgical management: a case report

We report the case of an adult patient with thumb polydactyly. The pre-axial thumb is in a non-functional flexion, while the 1st thumb maintains normal function. X-ray of the hand reveals a “T” shape 1st metacarpus bone, giving origin to the pre-axial polydactyly. Although this variation is not specifically described in the Wassel classification, we classify it as a type V of the Rotterdam´s classification. Patient is managed surgically, using a dynamic incision for polydactyly amputation. The polydactyly thumb has no identifiable muscle/tendon structures responsible of this unique deformation. The procedure results in good post-operative evolution with aesthetic scaring, and integral thumb function.

Neuronavigation-guided Endoscopic Endonasal Excision of Schwannoma-like Chordoma of Meckel's Cave: A Case Report

Chordomas are locally aggressive malignant tumors due to their recurrence potential and originate from embryonic notochord remnants. Chordomas can originate anywhere on the axial skeleton. They are extradural and spread by bone destruction. Chordomas are locally aggressive tumors that invade the dura mater, and may also present with secondary intradural growth. The Meckel's cave location of chordomas has been very rarely reported in the literature. Chordomas located in Meckel's cave can be radiologically confused with trigeminal schwannomas. Herein, we report a case of Meckel's cave chordoma that was successfully excised through neuronavigation-guided endoscopic endonasal excision, a technique commonly used in skull base surgeries.

Schwann Cell Precursor Transplant in a Rat Spinal Cord Injury Model

Background

Differentiation of mesenchymal stem cells into Schwann cell precursors could reverse established lesions and sequelae of medullary transection.

Objective

The objective of this study was to study the clinical response of mesenchymal stem cell transplantation with Schwann precursor cell transplantation in a rat spinal cord injury model, using motor function and histopathologic studies.

Materials and Methods

A total of 28 Sprague-Dawley rats were randomly divided among four groups (n = 7 in each): sham group, control group, mesenchymal stem cell transplant group, and Schwann cell precursor transplant group. The surgical procedure was a laminectomy with transection of the spinal cord at the T11 level in the transplant groups and the injury control group. After 1 week, the transplant groups received stem cells directly in the injury site. Hind limb motor function was assessed using the locomotive scale of Basso, Beattie, and Bresnahan. 1 month after transplantation, all specimens were sacrificed to make a histopathologic description of sections taken from the site of injury and where stem cells were transplanted. Mean scores of mobility were compared using analysis of variance (ANOVA) of one factor with 95% reliability between groups and ANOVA of repetitive measures to evaluate evolution in the same group.

Results

We observed that the control group had statistically greater mobility than the other groups (p < 0.0001) and that the group with spinal injury without treatment had the lowest mean mobility. The mobility score values from the Schwann cell precursor group were statistically higher than the group treated with mesenchymal stem cells (p < 0.0001).

Conclusion

Schwann precursor cells had a greater effect on locomotive function than mesenchymal stem cells.

Dermatology Surgery Training in a Live Animal Model

Background Surgical technique is an important part of resident training, which is the reason why various models have been implemented to acquire this skill. Animal models have been useful in teaching dermatologic suturing techniques. With the advancements in technology, simulators have been developed for these exercises, but at a very high cost. The use of pig heads and freshly killed animals have proven to be effective and low-cost. However, they do not reproduce skin pathologies with accuracy.

Objective To evaluate the effectiveness of a live anesthetized rat model to simulate skin pathologies requiring surgical excision in a dermatologic suture workshop for residents.

Methods We analyze the outcome of a theoretical and practical suturing workshop using live Wistar rats with 13 dermatology residents.

Results The residents showed an improvement in surgical maneuvers, suturing techniques, and in the use of surgical instruments (p < 0.01).

Conclusion The model proposed in the present study was economic, easy to obtain and to manage, and it portrays live and accurate skin response to manipulation. Therefore, it is effective for conducting surgical training sessions in dermatology.

Human Umbilical Vessels: Choosing the Optimal Decellularization Method

There is an increasing demand of small-diameter vascular grafts for treatment of circulatory pathologies. Decellularization offers the possibility of using human blood vessels as scaffolds to create vascular grafts. Umbilical vessels have great potential because of their availability and morphological characteristics. Various decellularization techniques have been used in umbilical vessels, but consensus on which is the most appropriate has not yet been reached. The objective of this review is to analyze the morphological and biomechanical characteristics of decellularized human umbilical arteries and veins with different techniques. Evidence indicates that the umbilical vessels are a viable option to develop small-diameter vascular grafts. Detergents are the agents most often used and with most evidence. However, further studies are needed to accurately analyze the components of the extracellular matrix and biomechanical characteristics, as well as the capacity for recellularization and in vivo functionality.

Conduits Used in Coronary Artery Bypass Grafting: A Review of Morphological Studies

There is a significant variety of vascular conduits options for coronary bypass surgery. Adequate graft selection is the most important factor for the success of the intervention. To ensure durability, permeability, and bypass function, there must be a morphological similarity between the graft and the coronary artery. The objective of this review was to analyze the morphological characteristics of the grafts that are most commonly used in coronary bypass surgery and the coronary arteries that are most frequently occluded. We included clinical information regarding the characteristics that determine the behavior of the grafts and its permeability over time. Currently, the internal thoracic artery is the standard choice for bypass surgery because of the morphological characteristics of the wall that makes less prone to developing atherosclerosis and hyperplasia. The radial and right gastroepiploic arteries are the following second and third best options, respectively. The ulnar artery is the preferred choice when other conduits are not feasible.

A modified chemical protocol of decellularization of rat sciatic nerve and its recellularization with mesenchymal differentiated schwann-like cells: morphological and functional assessments

The functional reconstruction of large neural defects usually requires the use of peripheral nerve autografts, though these have certain limitations. As a result, interest in new alternatives for autograft development has risen. The acellular peripheral nerve graft is an alternative for peripheral nerve injury repair, but to date there is not a standardized chemical decellularization method widely accepted. The objective of this study was to propose a modified chemical protocol of decellularization of rat sciatic nerve and its recellularization in vitro with mesenchimal differentiated Schwann-like cells. After the transplantation, an evaluation of its regeneration was performed using morphological and functional tests. The study consisted of two phases; in phase 1, different concentrations and times of exposure of rat sciatic nerves to detergents were tested, to establish a modified chemical protocol for nerve decellularization. The chemical treatment with 3% triton X-100 and 4% sodium deoxycholate for 15 days allowed a complete decellularization whilst conserving the extracellular matrix of the harvested nerve. In phase 2, the decellularized and recellularized alografts were compared against autografts. The morphological analysis showed a higher positivity to specific myelin antibodies in the recellularized group compared to the autograft. There were no differences in this parameter between the control limb and the experimental limb (recellularized group). The functional analysis showed no statistical differences at week 15 in the Sciatic Function Index in the autograft group vs the other groups. This study sets the morphological and functional bases for posterior studies about nerve defects regeneration in humans.

Morphological and histomorphometric evaluation of the ventral rectus sheath of the rectus abdominis muscle, fascia lata and pectoral fascia. The beginning of a morphological information bank of human fascias

The aim of this study was to characterize and compare the morphological and histomorphometric characteristics of the pectoral fascia, fascia lata and ventral rectus sheath. Twenty cadaveric samples of these fascias were analyzed and stained with hematoxylin and eosin, orcein, Van Gieson, Masson's trichrome and Verhoeff¨s stain (1200 slides in total). Morphological evaluation, semiquantitative, morphometric and microdensitometric analysis of elastic fibers present in each of the tissues and a morphometrical analysis of tissue thickness were performed. The mean value of the pectoral fascia thickness was 612±68.13 μm; 84±246 μm for the fascia lata and 584±92 μm for the ventral rectus sheath. The area occupied by the elastic fibers in the pectoral fascia was 12.24±5.84%; 6,54±3.85% for the fascia lata and 11.11±5.26% for the ventral rectus sheath. There were no statistically significant differences when comparing the mean values between the pectoral fascia and the ventral rectus sheath (p=0.07). There were statistically significant differences when comparing the fascia lata to the pectoral fascia and the ventral rectus sheath (p≤0.001). This study reports other morphological characteristics not described in previous histological studies of the analyzed tissues. The results of the morphometric and densitometric analysis in this study reveal that the fascia lata has the fewest elastic fibers of all the tissues analyzed, and the pectoral fascia has the most. These results will be useful for the beginning of a morphological information bank of human fascias.

Characterization and morphological comparison of human dura mater, temporalis fascia, and pericranium for the correct selection of an autograft in duraplasty procedures

PURPOSE

The objective of this study was to characterize and compare the morphological characteristics of the dura mater, the pericranium, and the temporal fascia to ascertain the most adequate tissue to use as a dura graft.

METHODS

20 dura mater, 20 pericranium and 20 temporalis fascia samples were analyzed. Each of the samples was stained with hematoxylin and eosin, orcein, Van Gieson, Masson's trichrome and Verhoeff-Van Gieson (600 slides in total) for a general morphological evaluation, as well as a quantitative, morphometric and densitometric analysis of elastic fibers present in each of the tissues.

RESULTS

The micro-densitometric analysis of the tissues indicated that the area occupied by the elastic fibers showed values of 1.766 ± 1.376, 4.580 ± 3.041, and 8.253 ± 4.467 % for the dura mater, the temporalis fascia and the pericranium, respectively (p < 0.05, all pairs). The values observed in the analysis of the density intensity were 3.42E+06 ± 2.57E+06, 1.41E+07 ± 1.28E+07, and 1.63E+07 ± 9.19E+06 for the dura mater, the temporalis fascia and the pericranium, respectively (p < 0.05), dura mater vs. temporalis fascia and dura mater vs. pericranium).

CONCLUSIONS

This is the first study to compare the dura mater with tissues for dural autograft and to quantify the elastic component present in these tissues. The results indicate that the temporalis fascia is a better dural graft because of its intrinsic tissue properties.

[New arthroscopic portal for performing tenotomy/tenodesis procedures on the long head of the biceps brachii tendon]

BACKGROUND

Shoulder arthroscopy is the standard technique for performing procedures involving the intertubercular groove. Current techniques continue to produce excessive soft tissue manipulation and neurovascular injury.

MATERIALS AND METHODS

A cross-sectional, observational and descriptive study was conducted on a cohort of 24 shoulders following the standard surgical protocol and using punch dissection. The neurovascular structures with risk of damage by the standard lateral portal were evaluated during the study to establish a secure area for a new arthroscopic portal. Finally, the safety of the new proposed site was evaluated.

RESULTS

The presence of 24 venous structures, with a mean diameter was 1.05mm (SD: 0.71) was documented. A tendency was observed in locating these structures in the lower half of the dissecting field for the left shoulders and a hypovascular area between the 7 and 10hours circle dissected relative to the right shoulder. The new site was determined at a point 1.5 cm anterolateral to the anterolateral border of the acromion at an angle of 60° degrees to the horizontal axis of the acromion and towards the intertubercular groove of the humerus.

CONCLUSIONS

The methodology used in this study is innovative, reproducible and applicable for the study of all existing shoulder arthroscopic portals procedures, as well as any joint. The results provided by this study will be helpful for clinicians to improve tenotomy/tendon tenodesis procedures of the long head of the biceps brachii tendon.

Clinical and surgical implications regarding morphometric variations of the medial wall of the orbit in relation to age and gender

The ethmoidal foramens are located on the medial wall of the orbit and are key reference points for intraoperative orientation. Detailed knowledge of the anatomy, bony landmarks and morphometric characteristics of the medial wall of the orbit is essential for various surgical procedures. The aim of this study was to determine the morphometric variations in the medial wall of the orbit and establish significant variations regarding age and gender. A total of 110 orbits were analyzed and subdivided by age (over or under 40 years) and gender. The distances of the medial wall of the orbit between the anterior lacrimal crest, the ethmoidal foramen, the optic canal and the interforamina were determined. Safe surgical areas were sought. Statistical tests were used to determine the differences between groups. In men, there is a safe surgical area proximal to the anterior and posterior ethmoidal foramen. In women, this area is in the posterior third of the medial wall of the orbit between the posterior ethmoidal foramen and the optic canal. Regarding variation according to age, the results of this study suggested that the anteroposterior diameter of the medial wall increases with age. This study showed that the anteroposterior total length of the medial orbit wall is similar between genders of similar age, increases with age, and has significant variations in the distances between the various structures that make up the medial orbit wall with regard to gender and age.