Trendelenburg (Head-Down tilt) and head rotation: Ultrasonographic effects on the internal jugular vein for catheterization safety.

Most guidelines fail to specify patient positioning during central venous catheterization. The objective was to determine the effects of head-down tilt (Trendelenburg position) and head rotation on the internal jugular vein (IJV). A prospective, observational, longitudinal, and descriptive study using healthy adult volunteers, of both sexes, was performed. The change in position and cross-sectional areas (CSA) of the right IJV and common carotid artery (CA) were measured by ultrasonography during Trendelenburg position (TP) (0°, 5°, 10°, and 15°) and contralateral head-rotation (HR) (0°, 45°, and 90°) for a total of 12 positions. The neutral supine position was first, randomizing the other 11 positions, with 5-min rest intervals in between. Vital signs and symptoms were recorded. A total of 54 volunteers were recruited between the ages of 21 and 32, of which 30 were men. Any degree of TP or HR significantly increased the CSA. The largest area obtained was 1.78 cm2 with a TP15HR90 which did not have a statistical difference with TP10HR45 1.59 cm2 . A HR90 tended to displace the IJV medially, overlaying the CA. Any degree of TP or HR will significantly increase CSA or the right IJV. A 5° to 10° TP is recommended when the patient's condition allows it, with a 45° HR, without significantly displacing the IJV anterior to the CCA.

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.

Trendelenburg position for internal jugular vein catheterization: A systematic review and meta-analysis.

To determine the effect of Trendelenburg position on the diameter or cross-section area of the internal jugular vein (IJV) a systematic review and metanalysis was performed. Studies that evaluated the cross-sectional area (CSA) and anteroposterior (AP) diameter of the right internal jugular vein (RIJV) with ultrasonography in supine and any degree of head-down tilt (Trendelenburg position) were analyzed. A total of 22 articles (613 study subjects) were included. A >5° Trendelenburg position statistically increases RIJV CSA and AP diameter. Further inclination from 10° does not statistically benefit IJV size. This position should be recommended for CVC placement, when patient conditions allow it, and US-guided cannulation is not available.

Anatomy of foot Compartments: a systematic review.

INTRODUCTION: There are discrepancies regarding the anatomy of the foot which complicate standardizing foot compartment treatment. We synthesized the existing evidence regarding the compartmental anatomy of the foot MATERIALS AND METHODS: A systematic review was performed evaluating the anatomy of the foot compartments in non-pathologic specimens. The search strategy was performed in MEDLINE, Scopus, Web of Science, and EMBASE. Three reviewers worked independently and in duplicate to screen all references via a title/abstract and full-text phase. The risk of bias was assessed with the Anatomical Quality Assurance (AQUA) checklist. RESULTS: Ten studies were included. All were performed in cadavers except one. Half of them evaluated the plantar section of the foot and the other half evaluated the whole foot. Methods employed across studies tended to vary: anatomical dissections, dye infusion, imaging studies, or a combination of these. Five studies directly addressed the anatomic limits of each compartment and eight addressed the anatomical structures inside each of them. There seems to be an agreement regarding the number of compartments in the plantar region (three major compartments divided by the medial and lateral intermuscular septum), nevertheless, disagreements across authors tend to arise when describing its dorsal section. Only two studies were ranked with an overall low risk of bias, agreeing on nine compartments. CONCLUSION: This review provides the best available anatomical evidence regarding the anatomy of the foot compartments for compartment syndrome management. Future research should focus on settling the discrepancies highlighted to reach a more accurate anatomical description.

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.

Collaborative mentoring for effective medical research groups.

This article was migrated. The article was marked as recommended. Research benefits professors and students, mentors and mentees, however, many Universities lack formal programs, especially in basic sciences such as anatomy. Faculty, many times, lack the time, resources, and a well-structured program. Mentoring and collaborative work, have played an important role in creating an effective environment that inspires its members into scientific production, enhances research skills, while gaining experience. The authors presented a student anatomy research group (Grupo de Investigación en Anatomía [GIA]) model that integrates faculty from basic and clinical fields through a collaborative mentoring and tightly organized structure that increases training, experience, and scientific output. The transformation stages described shows the progress, reporting the fundamental elements for integration of the model, with results presented at 16 years of experience of the group in the Anatomy department. Results evidence a steady increase in student/professor involvement, scientific publishing, presentations in meetings (national/international), and cites.