83,838 research outputs found

    Omental Vascularized Lymph Node Flap: A Radiographic Analysis

    Get PDF
    Background Vascularized lymph node transfer is an increasingly popular option for the treatment of lymphedema. The omental donor site is advantageous for its copious soft tissue, well-defined collateral circulation, and large number of available nodes, without the risk of iatrogenic lymphedema. The purpose of this study is to define the anatomy of the omental flap in the context of vascularized lymph node harvest. Methods Consecutive abdominal computed tomography angiography (CTA) images performed at a single institution over a 1-year period were reviewed. Right gastroepiploic artery (RGEA) length, artery caliber, lymph node size, and lymph node location in relation to the artery were recorded. A two-tailed Z-test was used to compare means. A Gaussian Mixture Model confirmed by normalized entropy criterion was used to calculate three-dimensional lymph node cluster locations along the RGEA. Results In total, 156 CTA images met inclusion criteria. The RGEA caliber at its origin was significantly larger in males compared with females (p < 0.001). An average of 3.1 (1.7) lymph nodes were present per patient. There was no significant gender difference in the number of lymph nodes identified. Average lymph node size was significantly larger in males (4.9 [1.9] × 3.3 [0.6] mm in males vs. 4.5 [1.5] × 3.1 [0.5] mm in females; p < 0.001). Three distinct anatomical variations of the RGEA course were noted, each with a distinct lymph node clustering pattern. Total lymph node number and size did not differ among anatomical subgroups. Conclusion The omentum is a reliable lymph node donor site with consistent anatomy. This study serves as an aid in preoperative planning for vascularized lymph node transfer using the omental flap

    Root anatomical traits contribute to deeper rooting of maize under compacted field conditions

    Get PDF
    © The Author(s) 2020. To better understand the role of root anatomy in regulating plant adaptation to soil mechanical impedance, 12 maize lines were evaluated in two soils with and without compaction treatments under field conditions. Penetrometer resistance was 1–2 MPa greater in the surface 30 cm of the compacted plots at a water content of 17–20% (v/v). Root thickening in response to compaction varied among genotypes and was negatively associated with rooting depth at one field site under non-compacted plots. Thickening was not associated with rooting depth on compacted plots. Genotypic variation in root anatomy was related to rooting depth. Deeper-rooting plants were associated with reduced cortical cell file number in combination with greater mid cortical cell area for node 3 roots. For node 4, roots with increased aerenchyma were deeper roots. A greater influence of anatomy on rooting depth was observed for the thinner root classes. We found no evidence that root thickening is related to deeper rooting in compacted soil; however, anatomical traits are important, especially for thinner root classes

    Popliteal lymph node dissection for metastatic squamous cell carcinoma: a case report of an uncommon procedure for an uncommon presentation

    Get PDF
    Lymph node metastasis from cutaneous squamous cell carcinoma is uncommon. The popliteal fossa is rarely involved with metastasis. Popliteal lymph node dissection is uncommonly performed and not frequently discussed in the literature. We present a case of squamous cell carcinoma of the heel with popliteal and inguinal metastasis. This is followed by a description of the relevant anatomy of the popliteal fossa and the technique of popliteal lymphadenectomy

    Esophageal submucosa: The watershed for esophageal cancer

    Get PDF
    ObjectivesSubmucosal esophageal cancers (pT1b) are considered superficial, implying good survival. However, some are advanced, metastasizing to regional lymph nodes. Interplay of cancer characteristics and lymphatic anatomy may create a watershed, demarcating low-risk from high-risk cancers. Therefore, we characterized submucosal cancers according to depth of invasion and identified those with high likelihood of lymph node metastases and poor survival.MethodsFrom 1983 to 2010, 120 patients underwent esophagectomy for submucosal cancers at Cleveland Clinic. Correlations were sought among cancer characteristics (location, dimensions, histopathologic cell type, histologic grade, and lymphovascular invasion [LVI]), and their associations with lymph node metastasis were identified by logistic regression. Associations with mortality were identified by Cox regression.ResultsAs submucosal invasion increased, cancer length (P < .001), width (P < .001), area (P < .001), LVI (P = .007), and grade (P = .05) increased. Invasion of the deep submucosa (P < .001) and LVI (P = .06) predicted lymph node metastases: 45% (23/51) of deep versus 10% (3/29) of middle-third and 7.5% (3/40) of inner-third cancers had lymph node metastases, as did 46% (12/26) with LVI versus 18% (17/94) without. Older age and lymph node metastases predicted worse 5-year survival: 94% for younger pN0 patients, 62% for older pN0 patients, and 36% for pN1-2 patients regardless of age.ConclusionsSubmucosal cancer characteristics and lymphatic anatomy create a watershed for regional lymph node metastases in the deep submucosa. This previously unrecognized divide distinguishes superficial submucosal cancers with good survival from deep submucosal cancers with poor survival. Aggressive therapy of more superficial cancers is critical before submucosal invasion occurs

    Embryological Development and Topographic Anatomy of Pelvic Compartments-Surgical Relevance for Pelvic Lymphonodectomy

    Get PDF
    Background The oncological outcome of surgery for the treatment of pelvic malignancies can be improved by performing pelvic lymphonodectomy. However, the extent and regions of lymph node harvest are debated and require profound knowledge of anatomy in order to avoid collateral damage. Methods The embryological development and topographic anatomy of pelvic compartments in relation to pelvic lymphonodectomy for rectal, uterine, and prostate cancer are reviewed. Based on pre-dissected anatomical specimens, lymph node regions and drainage routes of the posterior and urogenital pelvic compartments are described in both genders. Anatomical landmarks are highlighted to identify structures at risk of injury during pelvic lymphonodectomy. Results The ontogenesis of urogenital and anorectal compartments and their lymphatic supply are key factors for adequate lymphonodectomy, and have led to compartment-based surgical resection strategies. However, pelvic lymphonodectomy bears the risk of injury to somatic and autonomic nerves, vessels, and organs, depending on the regions and extent of surgery. Conclusion Embryologically defined, compartment-based resection of pelvic malignancies and their lymphatic drainage routes are based on clearly delineated anatomical landmarks, which permit template-oriented pelvic lymphonodectomy. Comprehensive knowledge of pelvic anatomy, the exchange of surgical concepts between specialties, and minimally invasive techniques will optimize pelvic lymphonodectomy and reduce complications

    The systematic anatomy of Grevilleeae and Persooniinae (proteaceae)

    Get PDF
    The anatomy of leaves was described for 91 species In the Grevilleeae and 15 species in the Persooniinae. The anatomy of the stem-node-leaf continuum was described for 57 species in the Grevilleeae and 6 species in the Persooniinae. Anatomical features were discussed in the context of taxonomic relationships in genera and, briefly, at higher levels. In Hakea, anatomical data supported the groupings proposed by taxonomists. In Grevillea, recognised natural groups were supported and anatomical features were useful in demonstrating homologies in the leaves of some Groups. In Persoonia anatomy supported some proposed groupings but, in others, anatomical characteristics showed considerable diversity. The variability of character states, homologies and homoplasies and the suitability of anatomical data for cladistic analyses was considered. A preliminary cladistic analysis was made and discussed

    Clinical Acceptability of Automatically Generated Lymph Node Levels and Structures of Deglutition and Mastication for Head and Neck Radiation Therapy

    Get PDF
    BACKGROUND AND PURPOSE: Auto-contouring of complex anatomy in computed tomography (CT) scans is a highly anticipated solution to many problems in radiotherapy. In this study, artificial intelligence (AI)-based auto-contouring models were clinically validated for lymph node levels and structures of swallowing and chewing in the head and neck. MATERIALS AND METHODS: CT scans of 145 head and neck radiotherapy patients were retrospectively curated. One cohort (n = 47) was used to analyze seven lymph node levels and the other (n = 98) used to analyze 17 swallowing and chewing structures. Separate nnUnet models were trained and validated using the separate cohorts. For the lymph node levels, preference and clinical acceptability of AI vs human contours were scored. For the swallowing and chewing structures, clinical acceptability was scored. Quantitative analyses of the test sets were performed for AI vs human contours for all structures using overlap and distance metrics. RESULTS: Median Dice Similarity Coefficient ranged from 0.77 to 0.89 for lymph node levels and 0.86 to 0.96 for chewing and swallowing structures. The AI contours were superior to or equally preferred to the manual contours at rates ranging from 75% to 91%; there was not a significant difference in clinical acceptability for nodal levels I-V for manual versus AI contours. Across all AI-generated lymph node level contours, 92% were rated as usable with stylistic to no edits. Of the 340 contours in the chewing and swallowing cohort, 4% required minor edits. CONCLUSIONS: An accurate approach was developed to auto-contour lymph node levels and chewing and swallowing structures on CT images for patients with intact nodal anatomy. Only a small portion of test set auto-contours required minor edits

    Function-based Intersubject Alignment of Human Cortical Anatomy

    Get PDF
    Making conclusions about the functional neuroanatomical organization of the human brain requires methods for relating the functional anatomy of an individual's brain to population variability. We have developed a method for aligning the functional neuroanatomy of individual brains based on the patterns of neural activity that are elicited by viewing a movie. Instead of basing alignment on functionally defined areas, whose location is defined as the center of mass or the local maximum response, the alignment is based on patterns of response as they are distributed spatially both within and across cortical areas. The method is implemented in the two-dimensional manifold of an inflated, spherical cortical surface. The method, although developed using movie data, generalizes successfully to data obtained with another cognitive activation paradigm—viewing static images of objects and faces—and improves group statistics in that experiment as measured by a standard general linear model (GLM) analysis

    Building a cell and anatomy ontology of Caenorhabditis elegans

    Get PDF
    We are endowed with a rich knowledge about Caenorhabditis elegans. Its stereotyped anatomy and development has stimulated research and resulted in the accumulation of cell-based information concerning gene expression, and the role of specific cells in developmental signalling and behavioural circuits. To make the information more accessible to sophisticated queries and automated retrieval systems, WormBase has begun to construct a C. elegans cell and anatomy ontology. Here we present our strategies and progress

    Towards Context Driven Modularization of Large Biomedical Ontologies

    Get PDF
    Formal knowledge about human anatomy, radiology or diseases is necessary to support clinical applications such as medical image search. This machine processable knowledge can be acquired from biomedical domain ontologies, which however, are typically very large and complex models. Thus, their straightforward incorporation into the software applications becomes difficult. In this paper we discuss first ideas on a statistical approach for modularizing large medical ontologies and we prioritize the practical applicability aspect. The underlying assumption is that the application relevant ontology fragments, i.e. modules, can be identified by the statistical analysis of the ontology concepts in the domain corpus. Accordingly, we argue that most frequently occurring concepts in the domain corpus define the application context and can therefore potentially yield the relevant ontology modules. We illustrate our approach on an example case that involves a large ontology on human anatomy and report on our first manual experiments
    corecore