Size Of Anatomical Structures Research Articles

A New Look at Structural Changes in the Aortic Root in Aortic Valve Stenosis.

The dataset of computed tomography angiography prior to aortic valve replacement in 262 patients was analyzed. The mean age was 75.0±5.9 years. 99 (37.8±3.0%) men and 163 (62.2±3.0%) women took part in the study. The annulus fibrosus, sinotubular junction, and height of the sinuses of Valsalva were measured. In the tricuspid aortic valve group (n=251), in more than 50% of the cases, the diameter of the annulus fibrosus ranged from 23 to 26 mm. No significant association between the diameter of the annulus fibrosus and patient height (r=0.35; p=0.01) or body surface area (r=0.25; p=0.01) and the height of the sinuses of Valsalva (r=0.34; p=0.01) were revealed. Based on the ratio of the height of the sinuses of Valsalva and the diameter of the annulus fibrosus, three variants of the structure of the aortic root were identified: type A - K>1.05; type B- 0.95≤K≤1.05; type C- K<0.95. Type C of the aortic root was found to predominate in most cases, namely, in 98.0±0.9% (n=246).In the bicuspid aortic valve group (n=11), 2 patients had a type A of the aortic root, 1 patient had a type B, and 8 patients had a type C. A classification of variants of the aortic root structure has been proposed, which will be useful not only for practitioners when choosing a treatment method, but also for researchers to understand the structural characteristics of the aortic root in patients with its pathology.

Comparison of Sizes of Anatomical Structures according to Scan Position Changes in Patients with Interstitial Lung Disease Using High-Resolution Thoracic CT

Comparison of Sizes of Anatomical Structures according to Scan Position Changes in Patients with Interstitial Lung Disease Using High-Resolution Thoracic CT

Morphometric analysis of mandibular corpus relevance to sagittal split osteotomy: Comparison of dentoskeletal Class I and Class III patients

IntroductionThe purpose of this study is to determine the 3-dimensional location of mandibular canal (MC), thickness of the cortical and cancellous bone at distal of 1st and 2nd mandibular molars in patients with Class 3 dentofacial deformity and compare with the dentoskeletal Class I individuals in relevance to sagittal split ramus osteotomy. MethodsThe study was conducted on CBCT images of 30 dentoskeletal Class I patients with a mean age of 22.9 years and 30 dentoskeletal Class III patients with a mean age of 21.27years. ResultsThe comparison of the measurements in the distal root of the first molar area showed that: thickness of the buccal cancellous bone, the distance from buccal aspect of MC to outer buccal cortical margin of mandible and the distance between superior aspect of MC and alveolar crest were significantly greater in Class I patients. The comparison of the measurements in the distal root of the second molar area showed that; the distance between superior aspect of MC and alveolar crest was significantly greater in Class I patients. However, the distances from the distal margin of mental foramen was significantly lower in Class I patients (P<0.05). ConclusionIn case of deviated skeletal development, position and size of anatomical structures can vary significantly. Prognathic mandibles has increased risk of neurovascular complications and bad splits. Morphologic data provided in this study may help practitioners for better surgical planning to reduce complications.

Anatomical Changes During Laparoscopic Procedures

Determining the exact sizes of anatomical structures play a very important today in laparoscopic surgery. This makes it possible to make a correct selection of gauges of instruments needed, prosthetic materials, and to make decisions regarding the further strategy of the surgical procedure. The device developed at the clinic has proven itself in everyday clinical practices. It is currently used in laparoscopic operations for hiatal hernias, choledoch measurements in patients with choledocholithiasis, stomach stump size measurements during the resection in patients with morbid obesity. The presented clinical case serves to confirm that obtaining objective data in video endoscopic surgery makes it possible to choose the optimal treatment strategy.

Published Human Cadaveric Measurements Are Strongly Biased Toward the Elderly Population.

Understanding of anatomy is based on the study of anatomical variations. Morphometric variations can have important implications in surgical practice. The sizes of some anatomical structures are affected by age; however, cadavers used in anatomical research are usually of advanced age. The main aim of this study is to quantify the mean age of samples in cadaveric studies reporting morphometric values. PubMed was searched for the last 3 years to locate cadaveric studies reporting size values, excluding histological, forensic, and osteological collections. Out of the 390 potentially relevant papers, 109 (28%) studies did not report the ages of their samples. In total, 177 studies were included for analysis comprising 4,807 subjects. The most studied structures were those of the musculoskeletal system. The mean age of the pooled sample was 71.1 ± 11.0 years. The lowest reported age was 16 while the highest was 104 years. Univariate and multivariate analyses showed no correlation with any of the following variables: country of study, anatomical region, anatomical structure, or journal type. The mean age of cadavers used to measure the sizes of human anatomical structures falls largely within the senior age category. The reported values in an aging population will not necessarily mirror other populations such as the pediatric. The outcomes of surgeries that depend to some extent on tight morphometric values such as flap surgeries, microsurgery, tendon transfer, or mini-invasive procedures could differ when they are performed on other age categories. More anatomical research is needed for better reporting of age-related morphometric changes. Clin. Anat., 33:804-808, 2020. © 2019 Wiley Periodicals, Inc.

AdaSLIC: adaptive supervoxel generation for volumetric medical images

In the last decade, supervoxels have become a useful mid-level representation of volumetric medical images such as MRIs and CT scans. Several methods were suggested to produce uniform supervoxels, yet little has been done to generate content-sensitive over-segmentations. This is particularly beneficial to 3D medical image analysis, where sizes of anatomical structures vary largely. In this paper, we propose AdaSLIC as an adaptive supervoxel generation technique that applies to volumetric medical images. In small structures, it generates tiny supervoxels to capture the details of the image. Meanwhile, it partitions large structures into bigger supervoxels, hence leading to a sparse description. The proposed technique is an extension of the Simple Linear Iterative Clustering (SLIC) algorithm. Rather than using a regular sampling to initiate supervoxel centers, a content-sensitive initialization is performed using a Poisson-disk sampling algorithm (PDS). It relies on a map of distances to the main image contours. The size of each supervoxel depends on the distance of its center to the closest image contour. We compare our algorithm to the SLIC algorithm as well as to an extension of the DBSCAN algorithm (Density-Based Spatial Clustering of Applications with Noise). Two datasets are used for this purpose: knee MRIs and cardiovascular magnetic resonance (CMR) images. We use different metrics to assess the quality of the generated over-segmentations. Experimental results show that our algorithm achieves comparable or better boundary adherence than the state of the art algorithms while producing compact and adaptive supervoxels.

Catastrophic Hand Injuries in Children

Objective: Catastrophic injuries of the hand are devastating and often lead to a significant functional and psychosocial disability. These injuries usually affect most hand structures (skin, soft tissues, bones, and joints) and compromise the function of the hand. The treatment objectives in these injuries are, in order of importance, save the life, save the limb, and restore the function. The initial care is one of the most important aspects in the treatment of catastrophic injuries of the hand. The general principles of management are debride devitalized tissue, restore the vascularization, provide rigid skeletal fixation, repair or reconstruct all damaged structures, and provide adequate soft tissue coverage. The concept of useful hand meets the following requirements: have at least 3 fingers of normal length, have at least proximal interphalangeal joint motion of the fingers, have near normal sensitivity, and have a functional opposing thumb or finger. Catastrophic injuries are not common in the pediatric population, but when they occur, they are often not properly managed. Around the world, many of the patients who suffer catastrophic injuries in the hand receive only skin coverage, and the hand reconstruction is made with secondary procedures, with poor functional results and lengthy hospital stays. Materials and Methods: We present our series of 25 cases of catastrophic hand injuries in pediatric patients aged 2 to 17 years with grade II to IV of the Hand Injury Severity Scoring System, which were managed by our team between 2010 and 2014. The main cause of injury was motor vehicle accident, followed by mangling by a machine. In all these patients, an attempt was made to repair or reconstruct all damaged structures in 1 surgical sitting, to avoid lengthy hospital stays, move the hand and fingers as quickly as possible, and diminish the psychological damage these injuries cause. Free flaps were used in 19 of the patients. No pedicled flaps were done in any of the patients, in order to be able to start the therapy program very early, sometimes on the first postoperative day. The range of surgical procedures performed in these patients was 1 to 3 surgeries. The initial reconstruction surgery was complemented in these cases with other 2 procedures such as flap thinning, hardware removal, secondary tendon grafting, etc. Results: Patients were assessed at least 1 year after the initial surgery with the Quick Disabilities of Arm, Shoulder and Hand (QuickDASH) disability instrument (which has been validated to use on older children). In average, all patients scored 18 or better. The patients and their parents also evaluated cosmetic appearance. Conclusions: It is very important to consider special factors in the pediatric population, such as the size of anatomical structures, compliance with treatment, rehabilitation of the patient, and the psychological and emotional complications for the child and their families. We show the importance of the initial total hand reconstruction in the pediatric population in the treatment of catastrophic injuries of the hand; this approach gives the child the opportunity to have an aesthetically acceptable and functional hand in the shortest time possible.

MODERN METHODS OF DIAGNOSIS IN ORTHODONTICS

The paper presents the possibilities of the virtual planning of orthodontic treatment with programs In Vivo Anatomage and 3Shape Ortho Analyzer, which allows you to create an individual plan of orthodontic treatment. Using three-dimensional cephalometric analysis and cone-beam computed tomography eliminates the risk of complications during orthodontic tooth moving. Aim - to determine the main directions of application of three-dimensional cephalometric analysis in orthodontist’s practice Materials and methods. The study involved 20 patients aged between 18 and 35 years (women 85%, men 15%). All patients underwent cone-beam computed tomography of the facial region of the skull conducted on a tomograph with a matrix 16h10. To obtain the most objective data, a wide range of clinical and other diagnostic methods was used in the study: clinical (survey, visual examination of face and oral cavity, clinical functional tests), anthropometric (measurement of jaw models in the program 3Shape Ortho Analyzer), CBCT of the facial region of the skull and cervical part of the spine. The survey was conducted on every patient according to the developed protocol. 1. Assessment of the dental hard tissues (diagnosis of caries, pulpitis and periodontitis), periapical periodontal tissues, and the state of the cortical bone; construction of three-dimensional panoramic reconstruction to determine the parallelism of the roots and their position in the bone of the alveolar processes on the vestibular and lingual surfaces. 2. Assessment of the patency of airways. 3. Evaluation of the bone elements of the temporomandibular joint on both sides, determining the position of articular head in the glenoid fossa. 4. Three-dimensional cephalometric analysis. 5. Superimposition of the data of the facial skull computed tomography; analysis of the changes in the course of dental treatment. The results of research. The obtained CBCT of the facial skull, processed in the program In Vivo Anatomage version 5.2, allows specifying the status and location of the bony structures of the temporomandibular joint, sinuses, individual structural features of the upper and lower jaws, dental roots deep in the alveolar processes and their correlation to the cortical plate. Additional features of the program are the opportunity to study the airways, combination of the scanned plaster models in .Stl format and superimposition of one CT scan to the other to produce a report on the changes that occurred. Discussion. The computer program allows correction of congenital abnormalities of dentition, reducing the risk of complications to a minimum. Moreover, the expected result can be predicted at the initial stage of treatment. The main advantage of CBCT is the possibility to determine the exact anatomical parameters of a patient without overlapping of adjacent structures and projection distortion of the sizes of anatomical structures.

Creation of a 3D printed temporal bone model from clinical CT data

PurposeGenerate and describe the process of creating a 3D printed, rapid prototype temporal bone model from clinical quality CT images. Materials and methodsWe describe a technique to create an accurate, alterable, and reproducible rapid prototype temporal bone model using freely available software to segment clinical CT data and generate three different 3D models composed of ABS plastic. Each model was evaluated based on the appearance and size of anatomical structures and response to surgical drilling. ResultsMastoid air cells had retained scaffolding material in the initial versions. This required modifying the model to allow drainage of the scaffolding material. External auditory canal dimensions were similar to those measured from the clinical data. Malleus, incus, oval window, round window, promontory, horizontal semicircular canal, and mastoid segment of the facial nerve canal were identified in all models. The stapes was only partially formed in two models and absent in the third. Qualitative feel of the ABS plastic was softer than bone. The pate produced by drilling was similar to bone dust when appropriate irrigation was used. ConclusionWe present a rapid prototype temporal bone model made based on clinical CT data using 3D printing technology. The model can be made quickly and inexpensively enough to have potential applications for educational training.

2D Histogram based volume visualization: combining intensity and size of anatomical structures

Surgical planning requires 3D volume visualizations based on transfer functions (TF) that assign optical properties to volumetric image data. Two-dimensional TFs and 2D histograms may be employed to improve overall performance. Anatomical structures were used for 2D TF definition in an algorithm that computes a new structure-size image from the original data set. The original image and structure-size data sets were used to generate a structure-size enhanced (SSE) histogram. Alternatively, the gradient magnitude could be used as second property for 2D TF definition. Both types of 2D TFs were generated and compared using subjective evaluation of anatomic feature conspicuity. Experiments with several medical image data sets provided SSE histograms that were judged subjectively to be more intuitive and better discriminated different anatomical structures than gradient magnitude-based 2D histograms. In clinical applications, where the size of anatomical structures is more meaningful than gradient magnitude, the 2D TF can be effective for highlighting anatomical structures in 3D visualizations.

Direct vs. inclusive fitness in the evolution of aphid cornicle length

By comparing the relative sizes of anatomical structures among phenotypes, selective pressures that shape species' morphologies can be evaluated. Aphids emit droplets containing an alarm pheromone/defensive secretion from unique anatomical structures called cornicles, upon being attacked. As aphids live in colonies of high relatedness, it is uncertain whether direct or inclusive fitness benefits have chiefly promoted cornicle evolution. Morphological measurements for apterous parthenogen, alate parthenogen, female sexual and male sexual morphs of 43 species (21 genera, one subfamily) were assessed to distinguish between the hypotheses that: (1) cornicles evolved for mechanical defence against natural enemies (direct fitness); (2) cornicles evolved for alarm signalling (inclusive fitness); or (3) cornicle length has been largely constrained by flight aerodynamics. Our results generally support the inclusive fitness hypothesis; cornicle length decreases as the relative number and relatedness of offspring decreases. As cornicle length is greatest in apterous parthenogenetic morphs, inclusive fitness benefits of protecting highly related kin may have been a key factor selecting for cornicles, and increased cornicle length, in aphids.

Comparative Assessment of the Effects of Livestock Grazing and Periodic Cutting on Steppe Plants of Tuva

A comparative study of the effects of heavy grazing load and periodic low cutting of above-ground phytomass on three plant species—Carex pediformis, Iris humilis, and Artemisia frigida—was performed in central Tuva in 1985–1989. Similar changes in the size of anatomical structures and ecophysiological characteristics of steppe plants were observed under the impact of both factors. They included signs of accelerated aging combined with adaptive reactions aimed at the most rapid development of shoots after the cessation of stress.

Regional differences in abdominal muscle activity during various maneuvers in humans.

To determine if regional differences exist in the activity of abdominal muscles during respiratory and nonrespiratory maneuvers, we studied four healthy subjects by comparing electromyographic (EMG) activity from surface electrodes placed lateral to rectus muscle, one pair on the upper abdomen and the other on the lower abdomen. In one subject EMG recordings were made from wires placed in various layers of the abdominal wall. Relative positions and changes in size of anatomic structures during maneuvers were determined from real-time ultrasonography of the abdominal wall. Expulsive or valsalva maneuvers evoked the same relative EMG activity in the upper and lower abdomen. In the resting supine posture no EMG activity was detectable; however, in the standing posture greater tonic EMG activity appeared in the lower abdomen. During rebreathing, phasic EMG activity during expiration was greater in the upper than in the lower abdomen in all subjects. Observations from ultrasonographic and electromyographic evaluations suggest that the control of abdominal muscles and their influence on respiratory mechanics are potentially more complex than has been suggested by previous reports.