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Sample records for anatomic landmarks based

  1. Collaborative regression-based anatomical landmark detection

    Gao, Yaozong; Shen, Dinggang

    2015-12-01

    Anatomical landmark detection plays an important role in medical image analysis, e.g. for registration, segmentation and quantitative analysis. Among the various existing methods for landmark detection, regression-based methods have recently attracted much attention due to their robustness and efficiency. In these methods, landmarks are localised through voting from all image voxels, which is completely different from the classification-based methods that use voxel-wise classification to detect landmarks. Despite their robustness, the accuracy of regression-based landmark detection methods is often limited due to (1) the inclusion of uninformative image voxels in the voting procedure, and (2) the lack of effective ways to incorporate inter-landmark spatial dependency into the detection step. In this paper, we propose a collaborative landmark detection framework to address these limitations. The concept of collaboration is reflected in two aspects. (1) Multi-resolution collaboration. A multi-resolution strategy is proposed to hierarchically localise landmarks by gradually excluding uninformative votes from faraway voxels. Moreover, for informative voxels near the landmark, a spherical sampling strategy is also designed at the training stage to improve their prediction accuracy. (2) Inter-landmark collaboration. A confidence-based landmark detection strategy is proposed to improve the detection accuracy of ‘difficult-to-detect’ landmarks by using spatial guidance from ‘easy-to-detect’ landmarks. To evaluate our method, we conducted experiments extensively on three datasets for detecting prostate landmarks and head & neck landmarks in computed tomography images, and also dental landmarks in cone beam computed tomography images. The results show the effectiveness of our collaborative landmark detection framework in improving landmark detection accuracy, compared to other state-of-the-art methods.

  2. Semi-Automatic Anatomical Tree Matching for Landmark-Based Elastic Registration of Liver Volumes

    Klaus Drechsler

    2010-01-01

    Full Text Available One promising approach to register liver volume acquisitions is based on the branching points of the vessel trees as anatomical landmarks inherently available in the liver. Automated tree matching algorithms were proposed to automatically find pair-wise correspondences between two vessel trees. However, to the best of our knowledge, none of the existing automatic methods are completely error free. After a review of current literature and methodologies on the topic, we propose an efficient interaction method that can be employed to support tree matching algorithms with important pre-selected correspondences or after an automatic matching to manually correct wrongly matched nodes. We used this method in combination with a promising automatic tree matching algorithm also presented in this work. The proposed method was evaluated by 4 participants and a CT dataset that we used to derive multiple artificial datasets.

  3. Anatomic Landmarks for the First Dorsal Compartment

    Hazani, Ron; Engineer, Nitin J.; Cooney, Damon; Wilhelmi, Bradon J.

    2009-01-01

    Objective: Knowledge of anatomic landmarks for the first dorsal compartment can assist clinicians with management of de Quervain's disease. The radial styloid, the scaphoid tubercle, and Lister's tubercle can be used as superficial landmarks for the first dorsal compartment. Methods: Thirty-two cadaveric wrists were dissected, and measurements were taken from the predetermined landmarks to the extensor retinaculum. The compartments were also inspected for variability of the abductor pollicis ...

  4. Anatomic landmarks for localization of the spinal accessory nerve.

    Durazzo, Marcelo D; Furlan, Julio C; Teixeira, Gilberto V; Friguglietti, Celso U M; Kulcsar, Marco A V; Magalhães, Roberto P; Ferraz, Alberto R; Brandão, Lenine G

    2009-05-01

    This anatomical study examines the anatomic topography and landmarks for localization of the spinal accessory nerve (SAN) during surgical dissections in 40 fresh human cadavers (2 females and 38 males; ages from 22 to 89 years with a mean of 60 years). In the submandibular region, the SAN was found anteriorly to the transverse process of the atlas in 77.5% of the dissections. When the SAN crossed the posterior belly of the digastric muscle, the mean distance from the point of crossing to the tendon of the muscle was 1.75 +/- 0.54 cm. Distally, the SAN crossed between the two heads of the SCM muscle in 45% of the dissections and deep to the muscle in 55%. The SAN exited the posterior border of the sternocleidomastoid muscle in a point superior to the nerve point with a mean distance between these two anatomic parameters of 0.97 +/- 0.46 cm. The mean overall extracranial length of the SAN was 12.02 +/- 2.32 cm, whereas the mean length of the SAN in the posterior triangle was 5.27 +/- 1.52 cm. There were 2-10 lymph nodes in the SAN chain. In conclusion, the nerve point is one of the most reliable anatomic landmarks for localization of the SAN in surgical neck dissections. Although other anatomic parameters including the transverse process of the atlas and the digastric muscle can also be used to localize the SAN, the surgeon should be aware of the possibility of anatomic variations of those parameters. Similar to previous investigations, our results suggest that the number of lymph nodes of the SAN chain greatly varies. PMID:19373901

  5. Anatomical landmarks accurately determine interfractional lymph node shifts during radiotherapy of lung cancer patients

    Background and purpose: Low contrast in the cone-beam computed tomography (CBCT) scans hampers fast online evaluation of interfractional changes in the lymph node position on a daily basis. In this study we have investigated whether high-contrast anatomical landmarks in the vicinity of the nodes may be used as surrogates for the lymph node positions. Materials and methods: Forty lung cancer patients were treated with an online CBCT-based setup strategy involving soft-tissue match on the primary tumor. One hundred and sixteen lymph nodes were delineated separately on the planning-CT scans and categorized according to the lymph node stations. Five anatomical landmarks were selected as surrogate structures and assigned to the individual nodes. In addition, the carina was delineated. Registrations between the planning-CT and the daily CBCTs were performed retrospectively and positional deviations between the nodes and the surrogate structures or the carina were registered. Results: The mean displacement between lymph nodes and surrogate structures was 1.6 mm with systematic/random errors of 0.7/0.7 mm, significantly smaller than the mean displacement between nodes and the carina. Conclusions: The position of the lymph nodes can be evaluated using selected anatomical landmarks on a daily basis using CBCT

  6. ANATOMICAL LANDMARKS FOR ROBOTIC NERVE SPARING RADICAL PROSTATECTOMY

    T. N. Moiseenko

    2013-01-01

    Full Text Available A detailed anatomical study of the prostate and pelvic organs has been recently relevant. Their anatomical knowledge is directly associated with the improved procedure of nerve-sparing robot-assisted radical prostatectomy, which contributes to the preservation of the anatomical structures responsible for postsurgical erection and urinary continence. The main tasks of radical prostatectomy are effective cancer control, early recovery of urinary continence, and recovery of erectile function.The literature on the anatomy of the prostate and its adjacent structures is analyzed in the context of nerve-sparing robot-assisted radical prostatectomy.

  7. Reproducibility of imaging skull anatomic landmarks utilizing three-dimensional computed tomography

    Sugawara, Yasushi; Harii, Kiyonori (Tokyo Univ. (Japan). Faculty of Medicine); Hirabayashi, Shinichi

    1994-05-01

    The study investigated the reproducibility of locating specific anatomic landmarks, utilizing computed tomography (CT), for the purpose of assigning accurate coordinates on the skull. Three-dimensional (3-D) CT data, obtained by scanning a dry adult skull, were processed using a multi-planar reconstruction (MPR) system. Each landmark was identified five times by the same technician, and the average distances between points identifying the same landmark were calculated. The 15 landmarks studied were the infra-orbital foramina, the external auditory meatus, the foramina rotundum, the foramina ovale, the optic canals, anterior crinoid processes, anterior nasal spine, crista galli, and the sella turcica. Three additional artificial markers placed in occlusal dental splints were also examined. The crinoid processes were identified with the highest degree of accuracy. The crista galli and optic canals were also located with reproducible results. The standard deviation calculated from the fine attempts to locate the artificial markers was smaller than that calculated from attempts to identify any of the landmarks. This implies that coordinates on the craniofacial bones should be defined using artificial markers rather than bony landmarks. Artificial markers placed in occlusal dental splints easily can be applied clinically. Complicated facial bone contours should be analyzed mathematically. In clinical setting, these points were found to be reproducible in 15 bony landmarks on the skull. (N.K.).

  8. Reproducibility of imaging skull anatomic landmarks utilizing three-dimensional computed tomography

    The study investigated the reproducibility of locating specific anatomic landmarks, utilizing computed tomography (CT), for the purpose of assigning accurate coordinates on the skull. Three-dimensional (3-D) CT data, obtained by scanning a dry adult skull, were processed using a multi-planar reconstruction (MPR) system. Each landmark was identified five times by the same technician, and the average distances between points identifying the same landmark were calculated. The 15 landmarks studied were the infra-orbital foramina, the external auditory meatus, the foramina rotundum, the foramina ovale, the optic canals, anterior crinoid processes, anterior nasal spine, crista galli, and the sella turcica. Three additional artificial markers placed in occlusal dental splints were also examined. The crinoid processes were identified with the highest degree of accuracy. The crista galli and optic canals were also located with reproducible results. The standard deviation calculated from the fine attempts to locate the artificial markers was smaller than that calculated from attempts to identify any of the landmarks. This implies that coordinates on the craniofacial bones should be defined using artificial markers rather than bony landmarks. Artificial markers placed in occlusal dental splints easily can be applied clinically. Complicated facial bone contours should be analyzed mathematically. In clinical setting, these points were found to be reproducible in 15 bony landmarks on the skull. (N.K.)

  9. Landmark Optimization Using Local Curvature for Point-Based Nonlinear Rodent Brain Image Registration

    Yutong Liu

    2012-01-01

    Full Text Available Purpose. To develop a technique to automate landmark selection for point-based interpolating transformations for nonlinear medical image registration. Materials and Methods. Interpolating transformations were calculated from homologous point landmarks on the source (image to be transformed and target (reference image. Point landmarks are placed at regular intervals on contours of anatomical features, and their positions are optimized along the contour surface by a function composed of curvature similarity and displacements of the homologous landmarks. The method was evaluated in two cases (=5 each. In one, MRI was registered to histological sections; in the second, geometric distortions in EPI MRI were corrected. Normalized mutual information and target registration error were calculated to compare the registration accuracy of the automatically and manually generated landmarks. Results. Statistical analyses demonstrated significant improvement (<0.05 in registration accuracy by landmark optimization in most data sets and trends towards improvement (<0.1 in others as compared to manual landmark selection.

  10. Forebrain development in fetal MRI: evaluation of anatomical landmarks before gestational week 27

    Schmook, Maria T.; Weber, Michael; Kasprian, Gregor; Nemec, Stefan; Prayer, Daniela [Medical University of Vienna, Department of Radiology/Division of Neuro- and Musculoskeletal Radiology, Vienna (Austria); Brugger, Peter C. [Medical University of Vienna, Integrative Morphology Group, Center for Anatomy and Cell Biology, Vienna (Austria); Krampl-Bettelheim, Elisabeth [Department of Obstetrics and Gynecology / Division of Obstetrics and Feto-maternal Medicine, Vienna (Austria)

    2010-06-15

    Forebrain malformations include some of the most severe developmental anomalies and require early diagnosis. The proof of normal or abnormal prosencephalic development may have an influence on further management in the event of a suspected fetal malformation. The purpose of this retrospective study was to evaluate the detectability of anatomical landmarks of forebrain development using in vivo fetal magnetic resonance imaging (MRI) before gestational week (gw) 27. MRI studies of 83 singleton fetuses (gw 16-26, average {+-}sd: gw 22 {+-} 2) performed at 1.5 Tesla were assessed. T2-weighted (w) fast spin echo, T1w gradient-echo and diffusion-weighted sequences were screened for the detectability of anatomical landmarks as listed below. The interhemispheric fissure, ocular bulbs, corpus callosum, infundibulum, chiasm, septum pellucidum (SP), profile, and palate were detectable in 95%, 95%, 89%, 87%, 82%, 81%, 78%, 78% of cases. Olfactory tracts were more easily delineated than bulbs and sulci (37% versus 18% and 8%), with significantly higher detection rates in the coronal plane. The pituitary gland could be detected on T1w images in 60% with an increasing diameter with gestational age (p=0.041). The delineation of olfactory tracts (coronal plane), chiasm, SP and pituitary gland were significantly increased after week 21 (p<0.05). Pathologies were found in 28% of cases. This study provides detection rates for anatomical landmarks of forebrain development with fetal MRI before gw 27. Several anatomical structures are readily detectable with routine fetal MRI sequences; thus, if these landmarks are not delineable, it should raise the suspicion of a pathology. Recommendations regarding favorable sequences/planes are provided. (orig.)

  11. Forebrain development in fetal MRI: evaluation of anatomical landmarks before gestational week 27

    Forebrain malformations include some of the most severe developmental anomalies and require early diagnosis. The proof of normal or abnormal prosencephalic development may have an influence on further management in the event of a suspected fetal malformation. The purpose of this retrospective study was to evaluate the detectability of anatomical landmarks of forebrain development using in vivo fetal magnetic resonance imaging (MRI) before gestational week (gw) 27. MRI studies of 83 singleton fetuses (gw 16-26, average ±sd: gw 22 ± 2) performed at 1.5 Tesla were assessed. T2-weighted (w) fast spin echo, T1w gradient-echo and diffusion-weighted sequences were screened for the detectability of anatomical landmarks as listed below. The interhemispheric fissure, ocular bulbs, corpus callosum, infundibulum, chiasm, septum pellucidum (SP), profile, and palate were detectable in 95%, 95%, 89%, 87%, 82%, 81%, 78%, 78% of cases. Olfactory tracts were more easily delineated than bulbs and sulci (37% versus 18% and 8%), with significantly higher detection rates in the coronal plane. The pituitary gland could be detected on T1w images in 60% with an increasing diameter with gestational age (p=0.041). The delineation of olfactory tracts (coronal plane), chiasm, SP and pituitary gland were significantly increased after week 21 (p<0.05). Pathologies were found in 28% of cases. This study provides detection rates for anatomical landmarks of forebrain development with fetal MRI before gw 27. Several anatomical structures are readily detectable with routine fetal MRI sequences; thus, if these landmarks are not delineable, it should raise the suspicion of a pathology. Recommendations regarding favorable sequences/planes are provided. (orig.)

  12. The secondary lobe as anatomic landmark for different pulmonary diseases

    The objective of this paper is to present the spectrum of pathological findings in the pulmonary parenchyma, based on the knowledge of the secondary lobe and its components. The evaluation was made using high-resolution computed tomography (HRCT) and compared with the histopathological findings. By definition, the secondary lobe is the small portion of pulmonary tissue separated by septa of connective tissue and supplied by 2-5 or more terminal bronchioles according to their central or peripheral location. Different disorders may become evident as a consequence of : 1) Bronchiolar obstruction (transient or definitive); 2) Intra-alveolar or wall involvement; 3) Involvement of the support tissue; 4) Involvement of the vascular or lymphatic structures. The etiology may be idiopathic, infectious, due to inhalation, neoplastic, allergic, due to collagen diseases, secondary to drug administration and/or post-transplantation. The evaluation of the secondary lobe components, with fine section HRCT, is the dynamic method of choice for the characterisation of pulmonary diseases, and allows to perform earlier and more precise differential diagnoses, when correlated with the clinical findings. The addition of sections during expiration to the routine study is paramount to underscore perfusion disturbances, which may remain undiagnosed during deep inspiration. The goal of this study is to review some of these disorders in which HRCT may be very useful and to correlate our observations with the histopathological findings. (author)

  13. Software Designation to Assess the Proximity of Different Facial Anatomic Landmarks to Midlines of the Mouth and Face

    Moshkelgosha V

    2014-12-01

    Full Text Available Statement of Problem: Recognition and determination of facial and dental midline is important in dentistry. Currently, there are no verifiable guidelines that direct the choice of specific anatomic landmarks to determine the midline of the face or mouth. Objectives: The purpose of this study was to determine which of facial anatomic landmarks is closest to the midline of the face as well as that of the mouth. Materials and Methods: Frontal full-face digital images of 92 subjects (men and women age range: 20-30 years in smile were taken under standardized conditions; commonly used anatomic landmarks, nasion, tip of the nose, and tip of the philtrum were digitized on the images of subjects and aesthetic analyzer software used for midline analysis using Esthetic Frame. Deviations from the midlines of the face and mouth were measured for the 3 clinical landmarks; the existing dental midline was considered as the fourth landmark. The entire process of midline analysis was done by a single observer and repeated twice. Reliability analysis and 1-sample t- tests were conducted. Results: The Intra-class correlation coefficients (ICCs for reliability analysis of RFV and RCV measures made two times revealed that the reliabilities were all acceptable. The results indicated that each of the 4 landmarks deviated uniquely and significantly (P<.001 from the midlines of the face as well as mouth in both males and females. Conclusions: There was a significant difference between the mean ratios of the chosen anatomic landmarks and the midlines of the face and mouth. The hierarchy of anatomic landmarks closest to the midline of the face is: (1 midline of the commissures, (2 nasion , (3 tip of philtrum,(4 dental midline, and (5 tip ofthe nose. The closest anatomic landmarks to the mouth midline are: (1 tip of philtrum, (2 dental midline, (3 tip of nose, and (4 nasion.

  14. Efficacy and costs comparison of anatomical landmarks and ultrasonic guidance during brachial plexus block

    Objective: To compare the efficacy and costs of brachial plexus block (BPB) guided by ultrasound with that used anatomical landmarks. Methods: Eighty ASA Ⅰ or Ⅱ patients scheduled for upper extremity operation were prospectively randomized into 2 groups: Group A (n=40, BPB using anatomical landmarks) and group U (n=40, BPB guided in real time by a two-dimensional ultrasonic image). The time spent on performing the block, the onset time and duration of analgesia were measured. The proportion of successful and excellent blocks and the incidence of complications were assessed. The cost of anesthetic and the total cost of anesthesia were recorded. Results: Compared with group A, in group U the time spent on performing the block and the onset time of analgesia were significantly shorter, the duration of analgesia was significantly longer, the excellence rate of block was significantly higher (all P<0.05). 95.0% of patients in group A and 97.5% of patients in group U had a successful block (P >0.05). Four patients in group A and two patients in group U had occurred complications (P>0.05). The cost of anesthetic in group U was significantly less than in group A (P<0.01). There was no significant difference in the total cost of anesthesia between the two groups (P>0.05). Conclusion: BPB guided by ultrasound provides better block with more rapid performance and longer duration of analgesia as compared with that used anatomical landmarks. Ultrasound-guided BPB is suitable for upper extremity operation and lowers the anesthetic cost. (authors)

  15. Impact of different anatomical landmarks on registration in imaging-guided radiation for lung cancer

    Objective: To evaluate the impact of different anatomical landmarks on registration in imaging-guided radiation (IGRT) for lung cancer. Methods: For 20 patients with non-small cell lung cancer receiving stereotactic body radiotherapy (SBRT) in Fudan University Cancer Hospital, 100 frames of kilo-voltage cone-beam computed tomography scanning were evaluated in this study. The spine, carina and tumor were selected as landmarks for registration, respectively. Results of registration using different landmarks were documented and compared. Results: The average set-up errors in the left-right, superior inferior and anterior-posterior directions were -0.08 cm ±0.32 cm, -0.16 cm ±0.45 cm and 0.06 cm ±0.23 cm with the spine for registration; 0.06 cm ±0.34 cm, -0.13 cm ±0.45 cm and -0.02 cm±0.23 cm with the carina; and -0.17 cm ±0.25 cm, 0.03 cm ±0.47 cm and 0.15 cm ±0.38 cm with tumor. The registration results between using the carina and tumor as landmarks were statistically significant different (q=4.61, P=0.002; q = 2.23 , P=0.118; q=3.44, P=0.017). The registration results were equal when using the spine and tumor as landmarks (q =1.85, P = 0.195; q = 2.54, P = 0.075; q = 1.89, P=0.185), as well as using the carina and tumor as landmarks (q=2.76, P=0.054; q=0.31, P=0.826; q=1.55, P=0.276). Conclusions: For early stage lung cancer, the spine and tumor can be used equally as registration landmarks in imaging-guided SBRT. The carina is not suggested for its poor reproducible position. (authors)

  16. An investigation on the facial midline distance to some anatomic landmarks of the jaws among people with natural dentition

    Mosharraf R

    2004-02-01

    Full Text Available The determination of the dental midline is necessary in most dental procedures."nOne of the methods to fulfill this goal is to determine the facial midline based on the midpoints of the"nforehead, nose, upper lip and chin. However, for various reasons, this method has not always been"nproved successful. In such cases, different techniques, based on the investigations in the edentulous"npatients, have been suggested."nPurpose: The aim of this study was to investigate the conformity of some landmarks such as labial"nfrenum, incisive papilla and mid palatal suture with dental and facial midlines among people with natural"ndentition in order to obtain accurate anatomic landmarks for denture replacement."nMaterials and Methods: In this descriptive study, 96 dental students, having all their permanent teeth"nand without any orthognathic problem, were chosen. For each subject, Alginate impressions and dental"ncasts were prepared. Then, centric occlusion was recorded with a biting wax and the facial mid line was"ndetermined on the anterior part of it. The distances from the facial midline to the upper teeth midline,"nincisive papilla, labial frenum and mid palatal suture were determined with a special tool and were"nmeasured by a VERNIEH two times. In order to analyze the results, Chi- Square and t-student tests were"nused."nResults: The average of facial midline distance to the upper teeth midline, the labial frenum, the incisive"npapilla and the mid palatal suture were 0.83±0.60, 0.67±G.54, 0.83±00.63 and 0.81±0.62 mm,"nrespectively. There was no significant difference between males and females. Labial frenum showed the"nminimum distance to the facial midline, while the incisive papilla had the maximum. There was no"nsignificant difference between these anatomic landmarks, in conformity or unconformity with the facial"nmidline"nConclusion: Considering the low percentage of the subjects with complete conformity and the lack of

  17. Enhancing SAT Based Planning with Landmark Knowledge

    Elffers, J.; Konijnenberg, D.; Walraven, E.M.P.; Spaan, M.T.J.

    2013-01-01

    Several approaches exist to solve Artificial Intelligence planning problems, but little attention has been given to the combination of using landmark knowledge and satisfiability (SAT). Landmark knowledge has been exploited successfully in the heuristics of classical planning. Recently it was also s

  18. Anatomic landmarks of fluoroscopy guided puncture of the pulseless femoral artery

    Jeon, Min Hee; Han, Gi Seok; Kim, Sung Jin; Park, Kil Sun; Cha, Sang Hoon; Bae, Il Hun; Lee, Seung Young [College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju (Korea, Republic of)

    2006-07-15

    We wanted to improve puncturing the pulseless femoral artery by evaluating the anatomic landmarks that suggest the course of the femoral artery on fluoroscopy. We analyzed 37 hemipelvis spot images that were centered on the arterial sheath after puncture of the femoral artery. The inguinal angles were measured between the inguinal line connecting the anterior superior iliac spine and the symphysis pubis, and the line of the arterial sheath. Inguinal ligament ratios were measured as the distance from the symphysis pubis to the arterial sheath to the length of the inguinal ligament on the inguinal line. The femoral head ratios were measured as the distance from the medial margin of the femur head to the arterial sheath to the transverse length of the femur head. The mean inguinal angle was 66.5 and the mean inguinal ligament ratio was 0.42 ({+-} 0.03). The mean femoral head ratio was 0.08 ({+-} 0.18). In comparing the men and women, there was no significant difference in the inguinal angle and the femoral head ratio, but the inguinal distance ratio was larger in women (men: 0.41 {+-} 0.033, women: 0.44 {+-} 0.031, {rho} < 0.05). The femoral artery generally courses just lateral to the medial margin of the femur head (femoral head ratio: 0.08) and the medial 40% of the inguinal ligament (inguinal ligament ratio: 0.42). So, consideration of these relations may be helpful for puncturing the pulseless femoral artery.

  19. Autonomous Robot Navigation based on Visual Landmarks

    Livatino, Salvatore

    2005-01-01

    autonomous navigation and self-localization using automatically selected landmarks. The thesis investigates autonomous robot navigation and proposes a new method which benefits from the potential of the visual sensor to provide accuracy and reliability to the navigation process while relying on naturally...... update of the estimated robot position while the robot is moving. In order to make the system autonomous, both acquisition and observation of landmarks have to be carried out automatically. The thesis consequently proposes a method for learning and navigation of a working environment and it explores......The use of landmarks for robot navigation is a popular alternative to having a geometrical model of the environment through which to navigate and monitor self-localization. If the landmarks are defined as special visual structures already in the environment then we have the possibility of fully...

  20. Anatomical landmarks and skin markers are not reliable for accurate labeling of thoracic vertebrae on MRI

    Background: Numbering of the thoracic spine on MRI can be tedious if C2 and L5-S1 are not included and may lead to errors in lesion level. Purpose: To determine whether anatomic landmarks or external markers are reliable as an aid for accurate numbering of thoracic vertebrae on MRI. Material and Methods: Sixty-seven thoracic spine MR studies of 67 patients (30 males, 37 females, age range 18-83 years) were studied, composed of 52 consecutive MR studies and an additional 15 MRI in which vitamin E markers were placed over the skin. In the 52 thoracic MR examinations potential numbering aids such as the level of the sternal apex, pulmonary artery, aortic arch, and osseous or disc abnormalities were numbered on both cervical localizer (standard of reference) and thoracic sagittal images. The additional 15 examinations in which vitamin E markers were placed over the skin were evaluated for consistency in the level of the markers on different sequences in the same exam. Results: The sternal apex level ranged from T2 to T5 [T3 in 28/51 patients (55%), T2 in 10/51 (20%)]. The aortic arch level ranged from T2 to T4 [T4 in 18/48 (38%) and T3 in 17 (35%)]. Pulmonary artery level ranged from T4 to T6-7 disc [T5 in 20/52 patients (38%) and T6 in 14/52 (27%)]. In 3 of 12 patients who had abnormalities in a vertebral body or disc as definite point reference, the non-localizer image mislabelled the level. In 11/15 (73%) patients with vitamin E markers that were placed over the upper thoracic spine, the results showed consistency in the level of the markers in relation to the reference points or consistent inter-marker gap between the sequences. Conclusion: There are only two reliable ways to accurately define the levels if no landmarking feature is available on the magnet. The first is by including C2 in the thoracic sequence of a diagnostic quality, and the second is by using an abnormality in the discs or vertebral bodies as a point of reference

  1. Dimensional ultrasonographic relationship of the right lobe of pancreas with associated anatomic landmarks in clinically normal dogs.

    Wickramasekara Rajapakshage, Bandula Kumara; Ellearaewe Garuhamilage, Janaka Pradeep Kumara; De Silva, Dona Daphney Niranjala; Dangolla, Ashoka

    2016-01-01

    The purpose of this prospective study was to establish the ultrasonographic characteristics of the dimension of the right pancreatic lobe with that of the associated anatomic landmarks in healthy dogs. Ultrasonographic examinations were performed on 25 dogs. The thickness of the right pancreatic lobe was compared with that of mural thickness of duodenum, diameter of duodenum, pancreatic duct, abdominal aorta, portal vein, caudal vena cava, and length and width of the right kidney and right adrenal gland. The correlation between each pancreatic parameter and the dimensions of the anatomical landmarks were assessed using linear regression analysis and Pearson's correlation coefficient (r) test. Significant, but weak linear correlations were observed between thickness of right pancreatic lobe with that of duodenum mural thickness (r=0.605, R(2)=0.339, P=0.001); duodenum diameter (r=0.573, R(2)=0.299, P=0.003); and right adrenal gland length (r=0.508, R(2)=0.052, P=0.01). There was no significant dimensional relationship with other selected anatomic landmarks. The ratio between the thickness of right pancreatic lobe and the mural thickness of duodenum, diameter of duodenum and length of right adrenal gland were 2.88 ± 0.53, 1.27 ± 0.27 and 0.81 ± 0.15, respectively. Calculating the ratio of thickness of the right pancreatic lobe with the dimension of significantly correlated anatomic landmarks is a useful and simple method for evaluating the size of the right pancreatic lobe in dogs in clinical practice. PMID:26234888

  2. The impact of reorienting cone-beam computed tomographic images in varied head positions on the coordinates of anatomical landmarks

    Kim, Jae Hun; Hwang, Jae Joon; Lee, Jung-Hee

    2016-01-01

    Purpose The aim of this study was to compare the coordinates of anatomical landmarks on cone-beam computed tomographic (CBCT) images in varied head positions before and after reorientation using image analysis software. Materials and Methods CBCT images were taken in a normal position and four varied head positions using a dry skull marked with 3 points where gutta percha was fixed. In each of the five radiographic images, reference points were set, 20 anatomical landmarks were identified, and each set of coordinates was calculated. Coordinates in the images from the normally positioned head were compared with those in the images obtained from varied head positions using statistical methods. Post-reorientation coordinates calculated using a three-dimensional image analysis program were also compared to the reference coordinates. Results In the original images, statistically significant differences were found between coordinates in the normal-position and varied-position images. However, post-reorientation, no statistically significant differences were found between coordinates in the normal-position and varied-position images. Conclusion The changes in head position impacted the coordinates of the anatomical landmarks in three-dimensional images. However, reorientation using image analysis software allowed accurate superimposition onto the reference positions. PMID:27358821

  3. Anatomic landmarks of fluoroscopy guided puncture of the pulseless femoral artery

    We wanted to improve puncturing the pulseless femoral artery by evaluating the anatomic landmarks that suggest the course of the femoral artery on fluoroscopy. We analyzed 37 hemipelvis spot images that were centered on the arterial sheath after puncture of the femoral artery. The inguinal angles were measured between the inguinal line connecting the anterior superior iliac spine and the symphysis pubis, and the line of the arterial sheath. Inguinal ligament ratios were measured as the distance from the symphysis pubis to the arterial sheath to the length of the inguinal ligament on the inguinal line. The femoral head ratios were measured as the distance from the medial margin of the femur head to the arterial sheath to the transverse length of the femur head. The mean inguinal angle was 66.5 and the mean inguinal ligament ratio was 0.42 (± 0.03). The mean femoral head ratio was 0.08 (± 0.18). In comparing the men and women, there was no significant difference in the inguinal angle and the femoral head ratio, but the inguinal distance ratio was larger in women (men: 0.41 ± 0.033, women: 0.44 ± 0.031, ρ < 0.05). The femoral artery generally courses just lateral to the medial margin of the femur head (femoral head ratio: 0.08) and the medial 40% of the inguinal ligament (inguinal ligament ratio: 0.42). So, consideration of these relations may be helpful for puncturing the pulseless femoral artery

  4. Iliohypogastric/ilioinguinal nerve block in inguinal hernia repair for postoperative pain management: comparison of the anatomical landmark and ultrasound guided techniques

    Abdurrahman Demirci; Esra Mercanoglu Efe; Gürkan Türker; Alp Gurbet; Fatma Nur Kaya; Ali Anil; İlker Çimen

    2014-01-01

    Objectives: The purpose of this study is to compare the efficacy of iliohypogastric/ilioinguinal nerve blocks performed with the ultrasound guided and the anatomical landmark techniques for postoperative pain management in cases of adult inguinal herniorrhaphy. Methods: 40 patients, ASA I-II status were randomized into two groups equally: in Group AN (anatomical landmark technique) and in Group ultrasound (ultrasound guided technique), iliohypogastric/ilioinguinal nerve block was performed w...

  5. Indoor monocular mobile robot navigation based on color landmarks

    LUO Yuan; ZHANG Bai-sheng; ZHANG Yi; LI Ling

    2009-01-01

    A robot landmark navigation system based on monocular camera was researched theoretically and experimentally. First the landmark setting and its data structure in programming was given; then the coordinates of them getting by robot and global localization of the robot was described; finally experiments based on Pioneer III mobile robot show that this system can work well at different topographic situation without lose of signposts.

  6. An analysis of anatomic landmark mobility and setup errors in radiotherapy for lung cancer

    case for the SD of the translations in the cranial direction of the clavicle, aortic arch and upper thoracic wall. The carina was found to be relatively mobile (up to 6 mm) in both directions. The SD for in-plane rotations was negligible (<0.5 deg.) for all structures. The interpatient variation was very small (SD < 0.5 mm). In a preliminary analysis of patient setup, the random errors for translations are 2.0 mm in the lateral direction and 2.4 mm in the cranial direction (1 SD). The standard deviations of systematic errors are about 3 mm in both directions. In plane rotations were found to be negligible. Conclusions: We have identified a number of structures which exhibit little internal motion in the frontal plane, and recommend that a combination of these structures be used as anatomic landmarks for setup verification during radiotherapy of thoracic tumors. Preliminary results indicate that setup errors of patients with lung cancer in our center appear to be acceptable, even though no specific immobilization devices were used

  7. Nasolacrimal Duct Orifice: A Cadaveric Study in Relation to Important Anatomical Landmarks

    Ankolekar, Vrinda Hari; Hosapatna, Mamatha; Das M, Aswin; Supriya, Supriya; Anne D Souza; Antony Sylvan D Souza

    2014-01-01

    AbstractThe nasolacrimal apparatus is intimately associated with the lateral nasal wall and may be approached using an endoscopic technique. This study was undertaken to describe in detail the gross anatomy of the nasolacrimal duct orifice in relation to various landmarks of the lateral nasal wall to improve the safety and efficiency of endoscopic surgical procedures. The study was conducted on 25 sagittal sections of adult cadavers in the Department of Anatomy, Kasturba Medical College, Mani...

  8. Adaptive Landmark-Based Navigation System Using Learning Techniques

    Zeidan, Bassel; Dasgupta, Sakyasingha; Wörgötter, Florentin;

    2014-01-01

    . Inspired by this, we develop an adaptive landmark-based navigation system based on sequential reinforcement learning. In addition, correlation-based learning is also integrated into the system to improve learning performance. The proposed system has been applied to simulated simple wheeled and more complex...

  9. Multirobot FastSLAM Algorithm Based on Landmark Consistency Correction

    Shi-Ming Chen

    2014-01-01

    Full Text Available Considering the influence of uncertain map information on multirobot SLAM problem, a multirobot FastSLAM algorithm based on landmark consistency correction is proposed. Firstly, electromagnetism-like mechanism is introduced to the resampling procedure in single-robot FastSLAM, where we assume that each sampling particle is looked at as a charged electron and attraction-repulsion mechanism in electromagnetism field is used to simulate interactive force between the particles to improve the distribution of particles. Secondly, when multiple robots observe the same landmarks, every robot is regarded as one node and Kalman-Consensus Filter is proposed to update landmark information, which further improves the accuracy of localization and mapping. Finally, the simulation results show that the algorithm is suitable and effective.

  10. Combining Speedup techniques based on Landmarks and Containers

    R. KALPANA

    2010-09-01

    Full Text Available The Dijkstra’s algorithm [1] , which is applied in many real world problems like mobile routing, road maps, railway networks, etc,. is used to find the shortest path between source and destination. There are many techniques available to speedup the algorithm while guaranteeing the optimality of the solution. The main focus of the work is to implement landmark technique and Containers separately and compare the results with random graphs and planar graphs. The combined speedup technique which is based on landmarks and containers were also experimented with random graphs and planar graphs to improvethe speedup of the shortest path queries.

  11. The relationship of maxillary canines to the facial anatomical landmarks in a group of Thai people

    Sinavarat, Potchaman; Anunmana, Chuchai; Hossain, Sharafat

    2013-01-01

    PURPOSE The objective was to evaluate canine positions, intercanine tip width (ICTW) and width of distal surface of canine (WDC), related to facial landmarks including interalar width (IAW), intercommissural width (ICoW), and distance between left and right projection lines drawn from inner canthus of eyes to alae of the nose (DPICa) in a group of Thai. MATERIALS AND METHODS One hundred Thai subjects aged 18-35 years were selected. IAW and ICoW were measured on subject's face using digital ve...

  12. Is the omega sign a reliable landmark for the neurosurgical team? An anatomical study about the central sulcus region

    Thiago Rodrigues

    2015-11-01

    Full Text Available ABSTRACTThe central sulcus region is an eloquent area situated between the frontal and parietal lobes. During neurosurgical procedures, it is sometimes difficult to understand the cortical anatomy of this region.Objective Find alternative ways to anatomically navigate in this region during neurosurgical procedures.Method We analyzed eighty two human hemispheres using a surgical microscope and completed a review of the literature about central sulcus region.Results In 68/82 hemispheres, the central sulcus did not reach the posterior ramus of the lateral sulcus. A knob on the second curve of the precentral gyrus was reliably identified in only 64/82 hemispheres.Conclusion The morphometric data presented in this article can be useful as supplementary method to identify the central sulcus region landmarks.

  13. An analysis of anatomic landmark mobility and setup deviations in radiotherapy for lung cancer

    Purpose: To identify thoracic structures that exhibit little internal motion during irradiation and to determine setup variations in patients with lung cancer. Methods and Materials: Intrafractional images were generated with an electronic portal-imaging device from the AP fields of 10 patients, during several fractions. To determine the intrafractional mobility of thoracic structures, visible structures were contoured in every image and matched with a reference image by means of a cross-correlation algorithm. Setup variations were determined by comparing portal images with the digitized simulator films using the stable structures as landmarks. Results: Mobility was limited in the lateral direction for the trachea, thoracic wall, paraspinal line, and aortic notch, and in the craniocaudal direction for the clavicle, aortic notch, and thoracic wall. Analysis of patient setup revealed random deviations of 2.0 mm (1 SD) in the lateral direction and 2.8 mm in the craniocaudal direction, while the systematic deviations were 2.5 and 2.0 mm (1 SD) respectively. Conclusions: We have identified thoracic structures that exhibit little internal motion in the frontal plane, and recommend that these structures be used for verifying patient setup during radiotherapy. The daily variation in the setup of lung cancer patients at our center appears to be acceptable

  14. Infraorbital nerve block within the Pterygopalatine fossa of the horse: anatomical landmarks defined by computed tomography

    In order to provide anaesthesia of the equine maxillary cheek teeth, a local nerve block of the infraorbital nerve in the pterygopalatine fossa had been proposed, which is referred to as the 'Palatine Bone Insertion' (PBI). As several complications with this method were reported, our study was designed to recommend a modified injection technique which avoids the risk of puncturing of relevant anatomical structures. Five cadaver heads and two living horses were examined by contrast medium injections and subsequent computed tomography (CT). Spinal needles were inserted using two different insertion techniques: The above mentioned (PBI), and a modification called 'Extraperiorbital Fat Body Insertion' (EFBI). Both techniques (PBI and EFBI) provide a consistent distribution of contrast medium around the infraorbital nerve. However, only the EFBI technique is appropriate to minimize the risk of complications. This study is an example for the permanent challenge of anatomists to supply a basis for clinical and surgical procedures

  15. Evaluation of polynomial image deformation for matching of 3D- abdominal MR-images using anatomical landmarks and for atlas construction

    Kimiaei, S; Jonsson, E; Crafoord, J; Maguire, G Q

    1999-01-01

    The aim of this study is to compare and evaluate the potential usability of linear and non-linear (polynomial) 3D-warping for constructing an atlas by matching abdominal MR-images from a number of different individuals using manually picked anatomical landmarks. The significance of this study lies in the fact that it illustrates the potential to use polynomial matching at a local or organ level. This is a necessary requirement for constructing an atlas and for fine intra-patient image matching and fusion. Finally 3D-image warping using anatomical landmark for inter-patient intra-modality image co-registration and fusion was found to be a very powerful and robust method. Additionally it can be used for intra-patient inter- modality image matching.

  16. Radiological diagnostics of abdomen and thorax. Image interpretation considering anatomical landmarks and clinical symptoms; Radiologische Diagnostik Abdomen und Thorax. Bildinterpretation unter Beruecksichtigung anatomischer Landmarken und klinischer Symptome

    Krombach, Gabriele A. [Universitaetsklinikum Giessen (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie; Mahnken, Andreas H. (ed.) [Universitaetsklinikum Marburg (Germany). Diagnostische und Interventionelle Radiologie

    2015-07-01

    The book on radiological diagnostics of abdomen and thorax - image interpretation considering anatomical landmarks and clinical symptoms - includes three chapters: (1) imaging of different parts of the body: thorax and abdomen. (II) Thorax: head and neck; mediastinum; heard and pericardium; large vessels; lungs and pleura; mamma. (III) Abdomen: liver; gall bladder and biliary tract; pancreas; gastrointestinal tract; spleen and lymphatic system; adrenal glands; kidneys and urinary tract; female pelvis; male pelvis.

  17. The Comparison of Learning Radiographic Extraoral Anatomic Landmarks through Lecture and blended method(Computer-Assisted teaching and Lecture:An interventional Study

    T ahmine Razi

    2013-05-01

    Full Text Available Introduction: One of the main problems in learning extraoral radiographic anatomic indexes is the long interval between presentation of radiology and human anatomy courses, resulting in forgetting anatomic regions. Therefore, radiographic indexes are formed as complete abstract and transient images in students’ minds; as a result, their learning and retention decrease. The aim of this study was to compare lecture with combination of computer-assisted learning and lecture of extra-oral radiographic landmarks among dental students. Methods: This interventional study was carried out in 2009 on 51 dental students of Tabriz University of Medical Sciences. Students were randomly allocated into two groups. The first group was taught through a teaching method which involved lectures in the classroom. In the second group, a CD was given to the students. The teaching was accomplished through presentation using skull. Six months after finishing the teaching, both groups took a similar test for evaluation of long term learning. The data was analyzed by SPSS 16 using U Mann-Whitney test. Results: There was no significant differences in the mean scores between the two groups in the first exam after teaching (P=0.13, yet it was significant in the second exam (regarding retention (P=0.006, and average of non-traditional teaching method group (20.89±10.23 was higher than that of lecture group (13.48±6.39. Conclusion: Based on the results, non-traditional technique of teaching was not more effective than the lecture in short-term learning but in longterm learning, non-traditional technique was more effective than the lecture.

  18. Iliohypogastric/ilioinguinal nerve block in inguinal hernia repair for postoperative pain management: comparison of the anatomical landmark and ultrasound guided techniques

    Abdurrahman Demirci

    2014-10-01

    Full Text Available Objectives:The purpose of this study is to compare the efficacy of iliohypogastric/ilioinguinal nerve blocks performed with the ultrasound guided and the anatomical landmark techniques for postoperative pain management in cases of adult inguinal herniorrhaphy.Methods:40 patients, ASA I-II status were randomized into two groups equally: in Group AN (anatomical landmark technique and in Group ultrasound (ultrasound guided technique, iliohypogastric/ilioinguinal nerve block was performed with 20 ml of 0.5% levobupivacaine prior to surgery with the specified techniques. Pain score in postoperative assessment, first mobilization time, duration of hospital stay, score of postoperative analgesia satisfaction, opioid induced side effects and complications related to block were assessed for 24 h postoperatively.Results:VAS scores at rest in the recovery room and all the clinical follow-up points were found significantly less in Group ultrasound (p < 0.01 or p < 0.001. VAS scores at movement in the recovery room and all the clinical follow-up points were found significantly less in Group ultrasound (p < 0.001 in all time points. While duration of hospital stay and the first mobilization time were being found significantly shorter, analgesia satisfaction scores were found significantly higher in ultrasound Group (p < 0.05, p < 0.001, p < 0.001 respectively.Conclusion:According to our study, US guided iliohypogastric/ilioinguinal nerve block in adult inguinal herniorrhaphies provides a more effective analgesia and higher satisfaction of analgesia than iliohypogastric/ilioinguinal nerve block with the anatomical landmark technique. Moreover, it may be suggested that the observation of anatomical structures with the US may increase the success of the block, and minimize the block-related complications.

  19. Automated Extraction of Cranial Landmarks from Computed Tomography Data using a Combined Method of Knowledge and Pattern Based Approaches

    Roshan N. RAJAPAKSE

    2016-03-01

    Full Text Available Accurate identification of anatomical structures from medical imaging data is a significant and critical function in the medical domain. Past studies in this context have mainly utilized two main approaches, the knowledge and learning methodologies based methods. Further, most of previous reported studies have focused on identification of landmarks from lateral X-ray Computed Tomography (CT data, particularly in the field of orthodontics. However, this study focused on extracting cranial landmarks from large sets of cross sectional CT slices using a combined method of the two aforementioned approaches. The proposed method of this study is centered mainly on template data sets, which were created using the actual contour patterns extracted from CT cases for each of the landmarks in consideration. Firstly, these templates were used to devise rules which are a characteristic of the knowledge based method. Secondly, the same template sets were employed to perform template matching related to the learning methodologies approach. The proposed method was tested on two landmarks, the Dorsum sellae and the Pterygoid plate, using CT cases of 5 subjects. The results indicate that, out of the 10 tests, the output images were within the expected range (desired accuracy in 7 instances and acceptable range (near accuracy for 2 instances, thus verifying the effectiveness of the combined template sets centric approach proposed in this study.

  20. Interfraction Displacement of Primary Tumor and Involved Lymph Nodes Relative to Anatomic Landmarks in Image Guided Radiation Therapy of Locally Advanced Lung Cancer

    Jan, Nuzhat; Balik, Salim; Hugo, Geoffrey D. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Mukhopadhyay, Nitai [Department of Biostatistics, Virginia Commonwealth University, Richmond, Virginia (United States); Weiss, Elisabeth, E-mail: eweiss@mcvh-vcu.edu [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States)

    2014-01-01

    Purpose: To analyze primary tumor (PT) and lymph node (LN) position changes relative to each other and relative to anatomic landmarks during conventionally fractionated radiation therapy for patients with locally advanced lung cancer. Methods and Materials: In 12 patients with locally advanced non-small cell lung cancer PT, LN, carina, and 1 thoracic vertebra were manually contoured on weekly 4-dimensional fan-beam CT scans. Systematic and random interfraction displacements of all contoured structures were identified in the 3 cardinal directions, and resulting setup margins were calculated. Time trends and the effect of volume changes on displacements were analyzed. Results: Three-dimensional displacement vectors and systematic/random interfraction displacements were smaller for carina than for vertebra both for PT and LN. For PT, mean (SD) 3-dimensional displacement vectors with carina-based alignment were 7 (4) mm versus 9 (5) mm with bony anatomy (P<.0001). For LN, smaller displacements were found with carina- (5 [3] mm, P<.0001) and vertebra-based (6 [3] mm, P=.002) alignment compared with using PT for setup (8 [5] mm). Primary tumor and LN displacements relative to bone and carina were independent (P>.05). Displacements between PT and bone (P=.04) and between PT and LN (P=.01) were significantly correlated with PT volume regression. Displacements between LN and carina were correlated with LN volume change (P=.03). Conclusions: Carina-based setup results in a more reproducible PT and LN alignment than bony anatomy setup. Considering the independence of PT and LN displacement and the impact of volume regression on displacements over time, repeated CT imaging even with PT-based alignment is recommended in locally advanced disease.

  1. Indirect building localization based on a prominent solid landmark from a forward-looking infrared imagery

    Xiaoping Wang; Tianxu Zhang; Xiaoyu Yang

    2011-01-01

    A novel indirect building localization technique based on a prominent solid landmark from a forwardlooking infrared imagery is proposed to localize low, deeply buried, or carefully camouflaged buildings in dense urban areas.First, the widely used effective methods are applied to detect and localize the solid landmark.The building target is then precisely indirectly localized by perspective transformation according to the imaging parameters and the space constraint relations between the building target and the solid landmark.Experimental results demonstrate this technique can indirectly localize buildings in dense urban areas effectively.%@@ A novel indirect building localization technique based on a prominent solid landmark from a forward-looking infrared imagery is proposed to localize low, deeply buried, or carefully camouflaged buildings in dense urban areas.First, the widely used effective methods are applied to detect and localize the solid landmark.The building target is then precisely indirectly localized by perspective transformation according to the imaging parameters and the space constraint relations between the building target and the solid landmark.Experimental results demonstrate this technique can indirectly localize buildings in dense urban areas effectively.

  2. Comparison of landmark-based and automatic methods for cortical surface registration.

    Pantazis, Dimitrios; Joshi, Anand; Jiang, Jintao; Shattuck, David W; Bernstein, Lynne E; Damasio, Hanna; Leahy, Richard M

    2010-02-01

    Group analysis of structure or function in cerebral cortex typically involves, as a first step, the alignment of cortices. A surface-based approach to this problem treats the cortex as a convoluted surface and coregisters across subjects so that cortical landmarks or features are aligned. This registration can be performed using curves representing sulcal fundi and gyral crowns to constrain the mapping. Alternatively, registration can be based on the alignment of curvature metrics computed over the entire cortical surface. The former approach typically involves some degree of user interaction in defining the sulcal and gyral landmarks while the latter methods can be completely automated. Here we introduce a cortical delineation protocol consisting of 26 consistent landmarks spanning the entire cortical surface. We then compare the performance of a landmark-based registration method that uses this protocol with that of two automatic methods implemented in the software packages FreeSurfer and BrainVoyager. We compare performance in terms of discrepancy maps between the different methods, the accuracy with which regions of interest are aligned, and the ability of the automated methods to correctly align standard cortical landmarks. Our results show similar performance for ROIs in the perisylvian region for the landmark-based method and FreeSurfer. However, the discrepancy maps showed larger variability between methods in occipital and frontal cortex and automated methods often produce misalignment of standard cortical landmarks. Consequently, selection of the registration approach should consider the importance of accurate sulcal alignment for the specific task for which coregistration is being performed. When automatic methods are used, the users should ensure that sulci in regions of interest in their studies are adequately aligned before proceeding with subsequent analysis. PMID:19796696

  3. Localization of skeletal and aortic landmarks in trauma CT data based on the discriminative generalized Hough transform

    Lorenz, Cristian; Hansis, Eberhard; Weese, Jürgen; Carolus, Heike

    2016-03-01

    Computed tomography is the modality of choice for poly-trauma patients to assess rapidly skeletal and vascular integrity of the whole body. Often several scans with and without contrast medium or with different spatial resolution are acquired. Efficient reading of the resulting extensive set of image data is vital, since it is often time critical to initiate the necessary therapeutic actions. A set of automatically found landmarks can facilitate navigation in the data and enables anatomy oriented viewing. Following this intention, we selected a comprehensive set of 17 skeletal and 5 aortic landmarks. Landmark localization models for the Discriminative Generalized Hough Transform (DGHT) were automatically created based on a set of about 20 training images with ground truth landmark positions. A hierarchical setup with 4 resolution levels was used. Localization results were evaluated on a separate test set, consisting of 50 to 128 images (depending on the landmark) with available ground truth landmark locations. The image data covers a large amount of variability caused by differences of field-of-view, resolution, contrast agent, patient gender and pathologies. The median localization error for the set of aortic landmarks was 14.4 mm and for the set of skeleton landmarks 5.5 mm. Median localization errors for individual landmarks ranged from 3.0 mm to 31.0 mm. The runtime performance for the whole landmark set is about 5s on a typical PC.

  4. Visual homing in the absence of feature-based landmark information.

    Gillner, Sabine; Weiss, Anja M; Mallot, Hanspeter A

    2008-10-01

    Despite that fact that landmarks play a prominent role in human navigation, experimental evidence on how landmarks are selected and defined by human navigators remains elusive. Indeed, the concept of a 'landmark' is itself not entirely clear. In everyday language, the term landmark refers to salient, distinguishable, and usually nameable objects, rendering the problem of landmark recognition a special case of the general object recognition problem. In contrast, in the insect and robot literature, this notion of landmarks is often replaced by the "local position information" [e.g., Trullier, O., Wiener, S., Berthoz, A., & Meyer, J.-A. (1997). Biologically based artificial navigation systems: Review and prospects. Progress in Neurobiology, 51, 483-544], referring to the entire set of sensor readings obtained at one location. This set may then serve as a characteristic of the particular location. Honey bees have been shown to base place recognition and homing on a snapshot-like memory of the place's visual environment, not on the distances to recognized objects [Cartwright, B., & Collett, T. (1983). Landmark learning in bees. Experiments and models. Journal of Comparative Physiology A, 151, 521-543]. A number of theoretical models of snapshot-based homing [e.g., Franz, M., Schölkopf, B., Mallot, H. A., Bülthoff, H. H. (1998). Where did I take that snapshot? Scene-based homing by image matching. Biological Cybernetics, 79, 191-202; Vardy, A., & Möller, R. (2005). Biologically plausible visual homing methods based on optical flow techniques. Connection Science, 17, 47-89] predict that the accuracy of snapshot-based homing should depend on image contrast. For rodent hippocampal place fields, models have been developed using additional image information such as three-dimensional depth and allocentric orientations (e.g., room axes) and are thus less sensitive to image contrast and noise [e.g. Barry, C., Lever, C., Hayman, R., Hartley, T., Burton, S., O'Keefe, J., et al

  5. Referências anatômicas na cirurgia do implante auditivo de tronco cerebral Anatomical landmarks in auditory brainstem implant surgery

    Rubens Vuono Brito Neto

    2005-06-01

    location of the insertion of the ABI electrode was studied through translabyrinthine access. RESULTS: The surgical technique used for implanting the brainstem electrode is similar to that used in the removal of vestibular schwannoma. The cochlear nucleus complex, comprising ventral and dorsal cochlear nuclei, is the optimal electrode site. The ventral cochlear nucleus is the principal nucleus for transmission of neural impulses from the 8th pair and form the main ascending route of the cochlear nerve. Neither the ventral nor the dorsal nuclei are visible during surgery and their location depends on the identification of adjacent anatomical structures. CONCLUSION: The region for the implantation of the electrode in the auditory brainstem implant presents anatomical landmarks that allow its easy identification during surgery.

  6. Comparison of landmark-based and automatic methods for cortical surface registration

    Pantazis, Dimitrios; Joshi, Anand; Jiang, Jintao; Shattuck, David; Bernstein, Lynne E.; Damasio, Hanna; Leahy, Richard M.

    2009-01-01

    Group analysis of structure or function in cerebral cortex typically involves as a first step the alignment of the cortices. A surface based approach to this problem treats the cortex as a convoluted surface and coregisters across subjects so that cortical landmarks or features are aligned. This registration can be performed using curves representing sulcal fundi and gyral crowns to constrain the mapping. Alternatively, registration can be based on the alignment of curvature metrics computed ...

  7. Knee joint secondary motion accuracy improved by quaternion-based optimizer with bony landmark constraints.

    Wang, Hongsheng; Zheng, Naiqaun Nigel

    2010-12-01

    Skin marker-based motion analysis has been widely used in biomechanical studies and clinical applications. Unfortunately, the accuracy of knee joint secondary motions is largely limited by the nonrigidity nature of human body segments. Numerous studies have investigated the characteristics of soft tissue movement. Utilizing these characteristics, we may improve the accuracy of knee joint motion measurement. An optimizer was developed by incorporating the soft tissue movement patterns at special bony landmarks into constraint functions. Bony landmark constraints were assigned to the skin markers at femur epicondyles, tibial plateau edges, and tibial tuberosity in a motion analysis algorithm by limiting their allowed position space relative to the underlying bone. The rotation matrix was represented by quaternion, and the constrained optimization problem was solved by Fletcher's version of the Levenberg-Marquardt optimization technique. The algorithm was validated by using motion data from both skin-based markers and bone-mounted markers attached to fresh cadavers. By comparing the results with the ground truth bone motion generated from the bone-mounted markers, the new algorithm had a significantly higher accuracy (root-mean-square (RMS) error: 0.7 ± 0.1 deg in axial rotation and 0.4 ± 0.1 deg in varus-valgus) in estimating the knee joint secondary rotations than algorithms without bony landmark constraints (RMS error: 1.7 ± 0.4 deg in axial rotation and 0.7 ± 0.1 deg in varus-valgus). Also, it predicts a more accurate medial-lateral translation (RMS error: 0.4 ± 0.1 mm) than the conventional techniques (RMS error: 1.2 ± 0.2 mm). The new algorithm, using bony landmark constrains, estimates more accurate secondary rotations and medial-lateral translation of the underlying bone. PMID:21142329

  8. Combining Speedup Techniques based on Landmarks and Containers with parallelised preprocessing in Random and Planar Graphs

    R. Kalpana

    2011-02-01

    Full Text Available The Dijkstra’s algorithm is applied in many real world problems like mobile routing, road maps,railway networks, etc,. There are many techniques available to speedup the algorithm while guaranteeingthe optimality of the solution. Almost all of the speedup techniques have a substantial amount of parallelism that can be exploited to decrease its running time. By suitably modifying portions of theexisting system various degrees of parallelism can be achieved. The rapidly growing field of multiprocessing systems and multi-core processors provide many opportunities for such improvements. Inthese techniques there’s always a demand for the running time and the time required for pre-processing.Space requirements for the pre-processing also have a major influence on the running time of thealgorithm. The main focus of the work is to implement landmark technique and to identify the segment of the code in landmark pre-processing which can be parallelized to obtain better speedup. The results are applied to the combined speedup technique which is based on landmarks and containers. The experimental results were compared and analysed for determining better performance improvements in random graphs and planar graphs.

  9. Percutaneous Placement of Central Venous Catheters: Comparing the Anatomical Landmark Method with the Radiologically Guided Technique for Central Venous Catheterization Through the Internal Jugular Vein in Emergent Hemodialysis Patients

    Koroglu, M.; Demir, M.; Koroglu, B.K.; Sezer, M.T.; Akhan, O.; Yildiz, H.; Yavuz, L.; Baykal, B.; Oyar, O. [Suleyman Demirel Univ., Isparta (Turkey). Depts. of Radiology, Internal Medicine and Anesthesiology

    2006-02-15

    Purpose: To compare the success and immediate complication rates of the anatomical landmark method (group 1) and the radiologically (combined real-time ultrasound and fluoroscopy) guided technique (group 2) in the placement of central venous catheters in emergent hemodialysis patients. Material and Methods: The study was performed prospectively in a randomized manner. The success and immediate complication rates of radiologically guided placement of central venous access catheters through the internal jugular vein (n = 40) were compared with those of the anatomical landmark method (n 40). The success of placement, the complications, the number of passes required, and whether a single or double-wall puncture occurred were also noted and compared. Results: The groups were comparable in age and sex. The indication for catheter placement was hemodialysis access in all patients. Catheter placement was successful in all patients in group 2 and unsuccessful in 1 (2.5%) patient in group 1. All catheters functioned adequately and immediately after the placement (0% initial failure rate) in group 2, but 3 catheters (7.5% initial failure rate) were non-functional just after placement in group 1. The total number of needle passes, double venous wall puncture, and complication rate were significantly lower in group 2. Conclusion: Percutaneous central venous catheterization via the internal jugular vein can be performed by interventional radiologists with better technical success rates and lower immediate complications. In conclusion, central venous catheterization for emergent dialysis should be performed under both real-time ultrasound and fluoroscopic guidance.

  10. Landmark based shape analysis for cerebellar ataxia classification and cerebellar atrophy pattern visualization

    Yang, Zhen; Abulnaga, S. Mazdak; Carass, Aaron; Kansal, Kalyani; Jedynak, Bruno M.; Onyike, Chiadi; Ying, Sarah H.; Prince, Jerry L.

    2016-03-01

    Cerebellar dysfunction can lead to a wide range of movement disorders. Studying the cerebellar atrophy pattern associated with different cerebellar disease types can potentially help in diagnosis, prognosis, and treatment planning. In this paper, we present a landmark based shape analysis pipeline to classify healthy control and different ataxia types and to visualize the characteristic cerebellar atrophy patterns associated with different types. A highly informative feature representation of the cerebellar structure is constructed by extracting dense homologous landmarks on the boundary surfaces of cerebellar sub-structures. A diagnosis group classifier based on this representation is built using partial least square dimension reduction and regularized linear discriminant analysis. The characteristic atrophy pattern for an ataxia type is visualized by sampling along the discriminant direction between healthy controls and the ataxia type. Experimental results show that the proposed method can successfully classify healthy controls and different ataxia types. The visualized cerebellar atrophy patterns were consistent with the regional volume decreases observed in previous studies, but the proposed method provides intuitive and detailed understanding about changes of overall size and shape of the cerebellum, as well as that of individual lobules.

  11. A landmark-based method for the geometrical 3D calibration of scanning microscopes

    Ritter, M.

    2007-04-27

    This thesis presents a new strategy and a spatial method for the geometric calibration of 3D measurement devices at the micro-range, based on spatial reference structures with nanometersized landmarks (nanomarkers). The new method was successfully applied for the 3D calibration of scanning probe microscopes (SPM) and confocal laser scanning microscopes (CLSM). Moreover, the spatial method was also used for the photogrammetric self-calibration of scanning electron microscopes (SEM). In order to implement the calibration strategy to all scanning microscopes used, the landmark-based principle of reference points often applied at land survey or at close-range applications has been transferred to the nano- and micro-range in the form of nanomarker. In order to function as a support to the nanomarkers, slope-shaped step pyramids have been developed and fabricated by focused ion beam (FIB) induced metal deposition. These FIB produced 3D microstructures have been sized to embrace most of the measurement volume of the scanning microscopes. Additionally, their special design allows the homogenous distribution of the nanomarkers. The nanomarkers were applied onto the support and the plateaus of the slope-step pyramids by FIB etching (milling) as landmarks with as little as several hundreds of nanometers in diameter. The nanomarkers are either of point-, or ring-shaped design. They are optimized so that they can be spatially measured by SPM and CLSM, and, imaged and photogrammetrically analyzed on the basis of SEM data. The centre of the each nanomarker serves as reference point in the measurement data or images. By applying image processing routines, the image (2D) or object (3D) coordinates of each nanomarker has been determined with subpixel accuracy. The correlative analysis of the SPM, CLSM and photogrammetric SEM measurement data after 3D calibration resulted in mean residues in the measured coordinates of as little as 13 nm. Without the coupling factors the mean

  12. Landmark-based shape analysis of the archaic Homo calvarium from Ceprano (Italy).

    Bruner, Emiliano; Manzi, Giorgio

    2007-03-01

    The Ceprano calvarium represents one of the most important sources of information about both the dynamics of the earliest hominid dispersal toward Europe and the evolution of the genus Homo in the early-to-middle Pleistocene. In this paper, the midsagittal vault profile and the 3D frontal bone morphology of Ceprano are investigated comparatively, using landmark coordinates and Procrustes superimposition. In fact, despite the fact that the skull appears partially distorted by diagenetic pressures (thus precluding a comprehensive landmark-based analysis), some aspects of the overall morphology are suitable for consideration in terms of geometric morphometrics. The midsagittal profile shows an archaic shape, comparable with the H. ergaster/erectus range of variation because of the fronto-parietal flattening, the development of the supraorbital and nuchal structures, and the occurrence of a slightly larger occipital bone. By contrast, the frontal bone displays a derived 3D shape that, mostly because of the widening of the frontal squama, appears comparable with the Afro-European variation of the Middle Pleistocene (i.e., H. heidelbergensis/rhodesiensis). Taking into account the unique morphological pattern displayed by Ceprano, its role as a link between early Homo and the Middle Pleistocene populations of Europe and Africa is not falsified. Thus, when aspects of the Ceprano's morphology are described within the analytical framework provided by geometric morphometrics, the relationships between Ceprano and the subsequent Afro-European fossil record are emphasized, suggesting the occurrence of an ancestral stock of H. heidelbergensis/rhodesiensis that is properly represented by the Italian specimen. PMID:17177181

  13. Flexible learning and use of multiple-landmark information by pigeons (Columba livia) in a touch screen-based goal searching task.

    Ushitani, Tomokazu; Jitsumori, Masako

    2011-08-01

    Three touch screen-based experiments were conducted to investigate whether pigeons would learn to use configural information about a goal's location in relation to a multiple-landmark array. In Experiment 1, 4 pigeons (Columba livia) were trained to peck a computer monitor at a location that constituted the third vertex of a hypothetical triangle defined by 2 different landmarks. The landmarks appeared in 3 orientations during the training, and the pigeons' goal-searching ability easily transferred to the landmarks presented in 3 novel orientations. Each landmark was asymmetric, so we next examined whether the pigeons used (a) the small-scale, local orientation information that could be inferred from each landmark individually, or (b) the large-scale, configural information that could be inferred from the spatial arrangement of multiple landmarks taken as a whole. Even when each single landmark appeared by itself, the pigeons were able to locate the goal accurately, suggesting that the large-scale, configural information was not essential. However, when 1 landmark locally pointed to a location that was consistent with the triangular configuration and the other landmark locally pointed to a different location, the pigeons predominantly pecked at the configurally array-consistent location. These results suggest that the pigeons redundantly learned both the large-scale, configural strategy and the local, single-landmark strategy, but they mainly used the latter information, and used the former information solely to disambiguate conflicts when the 2 landmarks pointed toward different targets. Such flexible learning and use of redundant information may reflect the pigeons' adaptation to unstable wild environments during their evolutionary history. PMID:21574692

  14. Measurement and clinical significance on anatomic landmark of anterior cervical decompression%颈椎前路减压手术解剖标志定位测量及其临床意义

    林永绥; 王万明; 张发惠; 郑和平; 王春

    2014-01-01

    Objective The primary purpose of the current study is to provide more scientific landmarks for safe and efficient decompression within limited operating field in cervical anterior decompression. Methods Relative data were observed and measured at C3~7 of 15 adult cadaveric specimens and some data were calculated basing on above data:the ratio of anterior crus of uncinate process-medial border of longus colli muscle distance and medial border of longus colli muscle-median sagittal plane distance(AULD/MLPD), the ratio of anterior crus of uncinate process- medial border of foramen transversarium distance and anterior crus of uncinate process-medial border of longus colli muscle distance (AUTD/AULD), the ratio of anterior crus of uncinate process-lateral border of dural sac perpendicular distance and posterior crus of uncinate process-lateral border of dural sac distance(AUDD/PUDD), and the ratio of the nearest point of uncinate process and nerve root-anterior crus of uncinate process perpendicular distance and anteroposterior crus of uncinate process perpendicular distance(UNAD/APUD). Results AULD/MLPD averaged 0.83 at C3, 0.55 at C4, 0.20 at C5, 0.34 at C6, and 0.27 at C7. AUTD/AULD averaged 2.71, AUDD/PUDD averaged 0.28, and UNAD/APUD averaged 0.34. Conclusion Anterior crus of uncinate process is a consistent anatomic landmark at anterior border of cervical vertebrae, which could serve as a stationary and reliable landmark in cervical anterior decompression, and facilitate the location of dural sac, cervical nerve root and vertebral artery during operation according to the ratios of AUDD/PUDD, UNAD/APUD and AUTD/AULD.%目的:为颈椎前路减压手术在有限显露术野中达到安全、有效减压提供更科学的减压标志。方法在15具成人尸体标本上,解剖观测C3~7节段相关解剖数据,以所测量的数据为基础,计算:(1)椎体钩前脚至颈长肌内侧缘的距离/颈长肌内侧缘至正中矢状面的距离(AULD/MLPD);(2

  15. Image-based dose planning of intracavitary brachytherapy: registration of serial-imaging studies using deformable anatomic templates

    cancer. These changes cannot be modeled by the conventional rigid landmark transformation method. In the current study, we found that the deformable anatomic template registration method, based on continuum-mechanics models of deformation, successfully described these large anatomic shape changes before and after ICT. These promising modeling results indicate that realistic registration of the cumulative dose distribution to the organs (or targets) of interest for radiation therapy of cervical cancers is achievable

  16. The Use of Quick Response (QR Codes in Landmark-Based Pedestrian Navigation

    Anahid Basiri

    2014-01-01

    Full Text Available Vehicle navigation systems usually simply function by calculating the shortest fastest route over a road network. In contrast, pedestrian navigation can have more diverse concerns. Pedestrians are not constrained to road/path networks; their route may involve going into buildings (where accurate satellite locational signals are not available and they have different priorities, for example, preferring routes that are quieter or more sheltered from the weather. In addition, there are differences in how people are best directed: pedestrians noticing landmarks such as buildings, doors, and steps rather than junctions and sign posts. Landmarks exist both indoors and outdoors. A system has been developed that uses quick response (QR codes affixed to registered landmarks allowing users to localise themselves with respect to their route and with navigational instructions given in terms of these landmarks. In addition, the system includes images of each landmark helping users to navigate visually in addition to through textual instructions and route maps. The system runs on a mobile device; the users use the device’s camera to register each landmark’s QR code and so update their position (particularly indoors and progress through the route itinerary.

  17. Landmark-based geometric morphometric analysis of wing shape among certain species of Aedes mosquitoes in District Dehradun (Uttarakhand), India

    Ritwik Mondal; Pemola Devi, N.; R.K. Jauhari

    2015-01-01

    Background & objectives: Insect wing morphology has been used in many studies to describe variations among species and populations using traditional morphometrics, and more recently geometric morphometrics. A landmark-based geometric morphometric analysis of the wings of three species of Aedes (Diptera: Culicidae), viz. Ae. aegypti, Ae. albopictus and Ae. pseudotaeniatus, at District Dehradun was conducted belling on the fact that it can provide insight into the population structure, ecology ...

  18. Dorsolateral Striatal Lesions Impair Navigation Based on Landmark-Goal Vectors but Facilitate Spatial Learning Based on a "Cognitive Map"

    Kosaki, Yutaka; Poulter, Steven L.; Austen, Joe M.; McGregor, Anthony

    2015-01-01

    In three experiments, the nature of the interaction between multiple memory systems in rats solving a variation of a spatial task in the water maze was investigated. Throughout training rats were able to find a submerged platform at a fixed distance and direction from an intramaze landmark by learning a landmark-goal vector. Extramaze cues were…

  19. Geodesic atlas-based labeling of anatomical trees

    Feragen, Aasa; Petersen, Jens; Owen, Megan; Lo, Pechin; Thomsen, Laura Hohwu; Wille, Mathilde Marie Winkler; Dirksen, Asger; de Bruijne, Marleen

    2015-01-01

    We present a fast and robust atlas-based algorithm for labeling airway trees, using geodesic distances in a geometric tree-space. Possible branch label configurations for an unlabeled airway tree are evaluated using distances to a training set of labeled airway trees. In tree-space, airway tree...... topology and geometry change continuously, giving a natural automatic handling of anatomical differences and noise. A hierarchical approach makes the algorithm efficient, assigning labels from the trachea and downwards. Only the airway centerline tree is used, which is relatively unaffected by pathology...

  20. Reliability of lower limb alignment measures using an established landmark-based method with a customized computer software program.

    Sled, Elizabeth A; Sheehy, Lisa M; Felson, David T; Costigan, Patrick A; Lam, Miu; Cooke, T Derek V

    2011-01-01

    The objective of the study was to evaluate the reliability of frontal plane lower limb alignment measures using a landmark-based method by (1) comparing inter- and intra-reader reliability between measurements of alignment obtained manually with those using a computer program, and (2) determining inter- and intra-reader reliability of computer-assisted alignment measures from full-limb radiographs. An established method for measuring alignment was used, involving selection of 10 femoral and tibial bone landmarks. (1) To compare manual and computer methods, we used digital images and matching paper copies of five alignment patterns simulating healthy and malaligned limbs drawn using AutoCAD. Seven readers were trained in each system. Paper copies were measured manually and repeat measurements were performed daily for 3 days, followed by a similar routine with the digital images using the computer. (2) To examine the reliability of computer-assisted measures from full-limb radiographs, 100 images (200 limbs) were selected as a random sample from 1,500 full-limb digital radiographs which were part of the Multicenter Osteoarthritis Study. Three trained readers used the software program to measure alignment twice from the batch of 100 images, with two or more weeks between batch handling. Manual and computer measures of alignment showed excellent agreement (intraclass correlations [ICCs] 0.977-0.999 for computer analysis; 0.820-0.995 for manual measures). The computer program applied to full-limb radiographs produced alignment measurements with high inter- and intra-reader reliability (ICCs 0.839-0.998). In conclusion, alignment measures using a bone landmark-based approach and a computer program were highly reliable between multiple readers. PMID:19882339

  1. Anatomically based lower limb nerve model for electrical stimulation

    Soboleva Tanya K

    2007-12-01

    Full Text Available Abstract Background Functional Electrical Stimulation (FES is a technique that aims to rehabilitate or restore functionality of skeletal muscles using external electrical stimulation. Despite the success achieved within the field of FES, there are still a number of questions that remain unanswered. One way of providing input to the answers is through the use of computational models. Methods This paper describes the development of an anatomically based computer model of the motor neurons in the lower limb of the human leg and shows how it can be used to simulate electrical signal propagation from the beginning of the sciatic nerve to a skeletal muscle. One-dimensional cubic Hermite finite elements were used to represent the major portions of the lower limb nerves. These elements were fit to data that had been digitised using images from the Visible Man project. Nerves smaller than approximately 1 mm could not be seen in the images, and thus a tree-branching algorithm was used to connect the ends of the fitted nerve model to the respective skeletal muscle. To simulate electrical propagation, a previously published mammalian nerve model was implemented and solved on the anatomically based nerve mesh using a finite difference method. The grid points for the finite difference method were derived from the fitted finite element mesh. By adjusting the tree-branching algorithm, it is possible to represent different levels of motor-unit recruitment. Results To illustrate the process of a propagating nerve stimulus to a muscle in detail, the above method was applied to the nerve tree that connects to the human semitendinosus muscle. A conduction velocity of 89.8 m/s was obtained for a 15 μm diameter nerve fibre. This signal was successfully propagated down the motor neurons to a selected group of motor units in the muscle. Conclusion An anatomically and physiologically based model of the posterior motor neurons in the human lower limb was developed. This

  2. The definitions of three-dimensional landmarks on the human face: an interdisciplinary view.

    Katina, Stanislav; McNeil, Kathryn; Ayoub, Ashraf; Guilfoyle, Brendan; Khambay, Balvinder; Siebert, Paul; Sukno, Federico; Rojas, Mario; Vittert, Liberty; Waddington, John; Whelan, Paul F; Bowman, Adrian W

    2016-03-01

    The analysis of shape is a key part of anatomical research and in the large majority of cases landmarks provide a standard starting point. However, while the technology of image capture has developed rapidly and in particular three-dimensional imaging is widely available, the definitions of anatomical landmarks remain rooted in their two-dimensional origins. In the important case of the human face, standard definitions often require careful orientation of the subject. This paper considers the definitions of facial landmarks from an interdisciplinary perspective, including biological and clinical motivations, issues associated with imaging and subsequent analysis, and the mathematical definition of surface shape using differential geometry. This last perspective provides a route to definitions of landmarks based on surface curvature, often making use of ridge and valley curves, which is genuinely three-dimensional and is independent of orientation. Specific definitions based on curvature are proposed. These are evaluated, along with traditional definitions, in a study that uses a hierarchical (random effects) model to estimate the error variation that is present at several different levels within the image capture process. The estimates of variation at these different levels are of interest in their own right but, in addition, evidence is provided that variation is reduced at the observer level when the new landmark definitions are used. PMID:26659272

  3. Dissimilarity-based classification of anatomical tree structures

    Sørensen, Lauge Emil Borch Laurs; Lo, Pechin Chien Pau; Dirksen, Asger; Petersen, Jens; de Bruijne, Marleen

    between the branch feature vectors representing those trees. Hereby, localized information in the branches is collectively used in classification and variations in feature values across the tree are taken into account. An approximate anatomical correspondence between matched branches can be achieved by......, as well as anatomical features to characterize each branch, an area under the receiver operating characteristic curve of 0.912 is achieved. This is significantly better than computing the average WA%....

  4. Dissimilarity-based classification of anatomical tree structures

    Sørensen, Lauge Emil Borch Laurs; Lo, Pechin Chien Pau; Dirksen, Asger; Petersen, Jens; de Bruijne, Marleen

    2011-01-01

    between the branch feature vectors representing those trees. Hereby, localized information in the branches is collectively used in classification and variations in feature values across the tree are taken into account. An approximate anatomical correspondence between matched branches can be achieved by......, as well as anatomical features to characterize each branch, an area under the receiver operating characteristic curveof 0.912 is achieved. This is significantly better than computing the average WA%....

  5. Reproducibility of the sella turcica landmark in three dimensions using a sella turcica-specific reference system

    Pittayapat, Pisha; Jacobs, Reinhilde [University Hospitals Leuven, University of Leuven, Leuven (Belgium); Odri, Guillaume A. [Service de Chirurgie Orthopedique et Traumatologique, Centre Hospitalier Regional d' Orleans, Orleans Cedex2 (France); De Faria Vasconcelos, Karla [Dept. of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Sao Paulo (Brazil); Willems, Guy [Dept. of Oral Health Sciences, Orthodontics, KU Leuven and Dentistry, University Hospitals Leuven, University of Leuven, Leuven (Belgium); Olszewski, Raphael [Dept. of Oral and Maxillofacial Surgery, Cliniques Universitaires Saint Luc, Universite Catholique de Louvain, Brussels (Belgium)

    2015-03-15

    This study was performed to assess the reproducibility of identifying the sella turcica landmark in a three-dimensional (3D) model by using a new sella-specific landmark reference system. Thirty-two cone-beam computed tomographic scans (3D Accuitomo 170, J. Morita, Kyoto, Japan) were retrospectively collected. The 3D data were exported into the Digital Imaging and Communications in Medicine standard and then imported into the Maxilim software (Medicim NV, Sint-Niklaas, Belgium) to create 3D surface models. Five observers identified four osseous landmarks in order to create the reference frame and then identified two sella landmarks. The x, y, and z coordinates of each landmark were exported. The observations were repeated after four weeks. Statistical analysis was performed using the multiple paired t-test with Bonferroni correction (intraobserver precision: p<0.005, interobserver precision: p<0.0011). The intraobserver mean precision of all landmarks was <1 mm. Significant differences were found when comparing the intraobserver precision of each observer (p<0.005). For the sella landmarks, the intraobserver mean precision ranged from 0.43±0.34 mm to 0.51±0.46 mm. The intraobserver reproducibility was generally good. The overall interobserver mean precision was <1 mm. Significant differences between each pair of observers for all anatomical landmarks were found (p<0.0011). The interobserver reproducibility of sella landmarks was good, with >50% precision in locating the landmark within 1 mm. A newly developed reference system offers high precision and reproducibility for sella turcica identification in a 3D model without being based on two-dimensional images derived from 3D data.

  6. Automatic landmark extraction from image data using modified growing neural gas network.

    Fatemizadeh, Emad; Lucas, Caro; Soltanian-Zadeh, Hamid

    2003-06-01

    A new method for automatic landmark extraction from MR brain images is presented. In this method, landmark extraction is accomplished by modifying growing neural gas (GNG), which is a neural-network-based cluster-seeking algorithm. Using modified GNG (MGNG) corresponding dominant points of contours extracted from two corresponding images are found. These contours are borders of segmented anatomical regions from brain images. The presented method is compared to: 1) the node splitting-merging Kohonen model and 2) the Teh-Chin algorithm (a well-known approach for dominant points extraction of ordered curves). It is shown that the proposed algorithm has lower distortion error, ability of extracting landmarks from two corresponding curves simultaneously, and also generates the best match according to five medical experts. PMID:12834162

  7. Neural Network-Based Landmark Recognition and Navigation with IAMRs. Understanding the Principles of Thought and Behavior.

    Doty, Keith L.

    1999-01-01

    Research on neural networks and hippocampal function demonstrating how mammals construct mental maps and develop navigation strategies is being used to create Intelligent Autonomous Mobile Robots (IAMRs). Such robots are able to recognize landmarks and navigate without "vision." (SK)

  8. Simultaneous detection of landmarks and key-frame in cardiac perfusion MRI using a joint spatial-temporal context model

    Lu, Xiaoguang; Xue, Hui; Jolly, Marie-Pierre; Guetter, Christoph; Kellman, Peter; Hsu, Li-Yueh; Arai, Andrew; Zuehlsdorff, Sven; Littmann, Arne; Georgescu, Bogdan; Guehring, Jens

    2011-03-01

    Cardiac perfusion magnetic resonance imaging (MRI) has proven clinical significance in diagnosis of heart diseases. However, analysis of perfusion data is time-consuming, where automatic detection of anatomic landmarks and key-frames from perfusion MR sequences is helpful for anchoring structures and functional analysis of the heart, leading toward fully automated perfusion analysis. Learning-based object detection methods have demonstrated their capabilities to handle large variations of the object by exploring a local region, i.e., context. Conventional 2D approaches take into account spatial context only. Temporal signals in perfusion data present a strong cue for anchoring. We propose a joint context model to encode both spatial and temporal evidence. In addition, our spatial context is constructed not only based on the landmark of interest, but also the landmarks that are correlated in the neighboring anatomies. A discriminative model is learned through a probabilistic boosting tree. A marginal space learning strategy is applied to efficiently learn and search in a high dimensional parameter space. A fully automatic system is developed to simultaneously detect anatomic landmarks and key frames in both RV and LV from perfusion sequences. The proposed approach was evaluated on a database of 373 cardiac perfusion MRI sequences from 77 patients. Experimental results of a 4-fold cross validation show superior landmark detection accuracies of the proposed joint spatial-temporal approach to the 2D approach that is based on spatial context only. The key-frame identification results are promising.

  9. Establishing Cephalometric Landmarks for the Translational Study of Le Fort-based Facial Transplantation in Swine: Enhanced applications using computer-assisted surgery and custom cutting guides

    Santiago, Gabriel F.; Susarla, Srinivas M.; Al Rakan, Mohammed; Coon, Devin; Rada, Erin M.; Sarhane, Karim; Shores, Jamie T.; Bonawitz, Steven C.; Cooney, Damon; Sacks, Justin; Murphy, Ryan J.; Fishman, Elliot K.; Brandacher, Gerald; Lee, WP Andrew; Liacouras, Peter; Grant, Gerald; Armand, Mehran; Gordon, Chad R.

    2014-01-01

    Background Le Fort-based, maxillofacial allotransplantation is a reconstructive alternative gaining clinical acceptance. However, the vast majority of single-jaw transplant recipients demonstrate less-than-ideal skeletal and dental relationships with suboptimal aesthetic harmony. The purpose of this study was to investigate reproducible cephalometric landmarks in a large animal model, where refinement of computer-assisted planning, intra-operative navigational guidance, translational bone osteotomies, and comparative surgical techniques could be performed. Methods Cephalometric landmarks that could be translated into the human craniomaxillofacial skeleton, and would remain reliable following maxillofacial osteotomies with mid-facial alloflap inset, were sought on six miniature swine. Le Fort I-and Le Fort III-based alloflaps were harvested in swine with osteotomies, and all alloflaps were either auto-replanted or transplanted. Cephalometric analyses were performed on lateral cephalograms pre- and post-operatively. Critical cephalometric data sets were identified with the assistance of surgical planning and virtual prediction software, and evaluated for reliability and translational predictability. Results Several pertinent landmarks and human analogues were identified including pronasale (PRN), zygion (Zy), parietale (PA), gonion (GO), gnathion (GN), lower incisior base (LIB), and alveolare (ALV). PA-PRN-ALV and PA-PRN-LIB were found to be reliable correlates of SNA and SNB measurements in humans, respectively. Conclusions There is a set of reliable cephalometric landmarks and measurement angles pertinent for utilization within a translational large animal model. These craniomaxillofacial landmarks will allow us to develop novel navigational software technology, improve our cutting guide designs, and explore new avenues for investigation and collaboration. Level of Evidence N/A (Large Animal Study) PMID:24445879

  10. Control over structure-specific flexibility improves anatomical accuracy for point-based deformable registration in bladder cancer radiotherapy

    Purpose: Future developments in image guided adaptive radiotherapy (IGART) for bladder cancer require accurate deformable image registration techniques for the precise assessment of tumor and bladder motion and deformation that occur as a result of large bladder volume changes during the course of radiotherapy treatment. The aim was to employ an extended version of a point-based deformable registration algorithm that allows control over tissue-specific flexibility in combination with the authors’ unique patient dataset, in order to overcome two major challenges of bladder cancer registration, i.e., the difficulty in accounting for the difference in flexibility between the bladder wall and tumor and the lack of visible anatomical landmarks for validation. Methods: The registration algorithm used in the current study is an extension of the symmetric-thin plate splines-robust point matching (S-TPS-RPM) algorithm, a symmetric feature-based registration method. The S-TPS-RPM algorithm has been previously extended to allow control over the degree of flexibility of different structures via a weight parameter. The extended weighted S-TPS-RPM algorithm was tested and validated on CT data (planning- and four to five repeat-CTs) of five urinary bladder cancer patients who received lipiodol injections before radiotherapy. The performance of the weighted S-TPS-RPM method, applied to bladder and tumor structures simultaneously, was compared with a previous version of the S-TPS-RPM algorithm applied to bladder wall structure alone and with a simultaneous nonweighted S-TPS-RPM registration of the bladder and tumor structures. Performance was assessed in terms of anatomical and geometric accuracy. The anatomical accuracy was calculated as the residual distance error (RDE) of the lipiodol markers and the geometric accuracy was determined by the surface distance, surface coverage, and inverse consistency errors. Optimal parameter values for the flexibility and bladder weight

  11. Landmarks in Hybrid Planning

    Mohamed Elkawkagy

    2013-11-01

    Full Text Available Although planning techniques achieved a significant progress during recent years, solving many planning problem still difficult even for modern planners. In this paper, we will adopt landmark concept to hybrid planning setting - a method that combines reasoning about procedural knowledge and causalities. Land-marks are a well-known concept in the realm of classical planning. Recently, they have been adapted to hierarchical approaches. Such landmarks can be extracted in a pre-processing step from a declarative hierarchical planning domain and problem description. It was shown how this technique allows for a considerable reduction of the search space by eliminating futile plan development options before the actual planning. Therefore, we will present a new approach to in¬tegrate landmark pre-processing technique in the context of hierarchical planning with landmark technique in the classical planning. This integration allows to incorporate the ability of using extracted landmark tasks from hierarchical domain knowledge in the form of HTN and using landmark literals from classical planning. To this end, we will construct a transformation technique to transform the hybrid planning domain into a classical domain model. The method¬ologies in this paper have been implemented successfully, and we will present some experimental results that give evidence for the consid-erable performance increase gained through planning system.

  12. Do Humans Integrate Routes Into a Cognitive Map? Map- Versus Landmark-Based Navigation of Novel Shortcuts

    Foo, Patrick; Warren, William H.; Duchon, Andrew; Tarr, Michael J.

    2005-01-01

    Do humans integrate experience on specific routes into metric survey knowledge of the environment, or do they depend on a simpler strategy of landmark navigation? The authors tested this question using a novel shortcut paradigm during walking in a virtual environment. The authors find that participants could not take successful shortcuts in a…

  13. Visual EKF-SLAM from Heterogeneous Landmarks

    Jorge Othón Esparza-Jiménez

    2016-04-01

    Full Text Available Many applications require the localization of a moving object, e.g., a robot, using sensory data acquired from embedded devices. Simultaneous localization and mapping from vision performs both the spatial and temporal fusion of these data on a map when a camera moves in an unknown environment. Such a SLAM process executes two interleaved functions: the front-end detects and tracks features from images, while the back-end interprets features as landmark observations and estimates both the landmarks and the robot positions with respect to a selected reference frame. This paper describes a complete visual SLAM solution, combining both point and line landmarks on a single map. The proposed method has an impact on both the back-end and the front-end. The contributions comprehend the use of heterogeneous landmark-based EKF-SLAM (the management of a map composed of both point and line landmarks; from this perspective, the comparison between landmark parametrizations and the evaluation of how the heterogeneity improves the accuracy on the camera localization, the development of a front-end active-search process for linear landmarks integrated into SLAM and the experimentation methodology.

  14. Visual EKF-SLAM from Heterogeneous Landmarks.

    Esparza-Jiménez, Jorge Othón; Devy, Michel; Gordillo, José L

    2016-01-01

    Many applications require the localization of a moving object, e.g., a robot, using sensory data acquired from embedded devices. Simultaneous localization and mapping from vision performs both the spatial and temporal fusion of these data on a map when a camera moves in an unknown environment. Such a SLAM process executes two interleaved functions: the front-end detects and tracks features from images, while the back-end interprets features as landmark observations and estimates both the landmarks and the robot positions with respect to a selected reference frame. This paper describes a complete visual SLAM solution, combining both point and line landmarks on a single map. The proposed method has an impact on both the back-end and the front-end. The contributions comprehend the use of heterogeneous landmark-based EKF-SLAM (the management of a map composed of both point and line landmarks); from this perspective, the comparison between landmark parametrizations and the evaluation of how the heterogeneity improves the accuracy on the camera localization, the development of a front-end active-search process for linear landmarks integrated into SLAM and the experimentation methodology. PMID:27070602

  15. Near Real-Time Assessment of Anatomic and Dosimetric Variations for Head and Neck Radiation Therapy via Graphics Processing Unit–based Dose Deformation Framework

    Qi, X. Sharon, E-mail: xqi@mednet.ucla.edu [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Santhanam, Anand; Neylon, John; Min, Yugang; Armstrong, Tess; Sheng, Ke [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Staton, Robert J.; Pukala, Jason [Department of Radiation Oncology, UF Health Cancer Center - Orlando Health, Orlando, Florida (United States); Pham, Andrew; Low, Daniel A.; Lee, Steve P. [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Steinberg, Michael; Manon, Rafael [Department of Radiation Oncology, UF Health Cancer Center - Orlando Health, Orlando, Florida (United States); Chen, Allen M.; Kupelian, Patrick [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)

    2015-06-01

    Purpose: The purpose of this study was to systematically monitor anatomic variations and their dosimetric consequences during intensity modulated radiation therapy (IMRT) for head and neck (H&N) cancer by using a graphics processing unit (GPU)-based deformable image registration (DIR) framework. Methods and Materials: Eleven IMRT H&N patients undergoing IMRT with daily megavoltage computed tomography (CT) and weekly kilovoltage CT (kVCT) scans were included in this analysis. Pretreatment kVCTs were automatically registered with their corresponding planning CTs through a GPU-based DIR framework. The deformation of each contoured structure in the H&N region was computed to account for nonrigid change in the patient setup. The Jacobian determinant of the planning target volumes and the surrounding critical structures were used to quantify anatomical volume changes. The actual delivered dose was calculated accounting for the organ deformation. The dose distribution uncertainties due to registration errors were estimated using a landmark-based gamma evaluation. Results: Dramatic interfractional anatomic changes were observed. During the treatment course of 6 to 7 weeks, the parotid gland volumes changed up to 34.7%, and the center-of-mass displacement of the 2 parotid glands varied in the range of 0.9 to 8.8 mm. For the primary treatment volume, the cumulative minimum and mean and equivalent uniform doses assessed by the weekly kVCTs were lower than the planned doses by up to 14.9% (P=.14), 2% (P=.39), and 7.3% (P=.05), respectively. The cumulative mean doses were significantly higher than the planned dose for the left parotid (P=.03) and right parotid glands (P=.006). The computation including DIR and dose accumulation was ultrafast (∼45 seconds) with registration accuracy at the subvoxel level. Conclusions: A systematic analysis of anatomic variations in the H&N region and their dosimetric consequences is critical in improving treatment efficacy. Nearly real

  16. Near Real-Time Assessment of Anatomic and Dosimetric Variations for Head and Neck Radiation Therapy via Graphics Processing Unit–based Dose Deformation Framework

    Purpose: The purpose of this study was to systematically monitor anatomic variations and their dosimetric consequences during intensity modulated radiation therapy (IMRT) for head and neck (H&N) cancer by using a graphics processing unit (GPU)-based deformable image registration (DIR) framework. Methods and Materials: Eleven IMRT H&N patients undergoing IMRT with daily megavoltage computed tomography (CT) and weekly kilovoltage CT (kVCT) scans were included in this analysis. Pretreatment kVCTs were automatically registered with their corresponding planning CTs through a GPU-based DIR framework. The deformation of each contoured structure in the H&N region was computed to account for nonrigid change in the patient setup. The Jacobian determinant of the planning target volumes and the surrounding critical structures were used to quantify anatomical volume changes. The actual delivered dose was calculated accounting for the organ deformation. The dose distribution uncertainties due to registration errors were estimated using a landmark-based gamma evaluation. Results: Dramatic interfractional anatomic changes were observed. During the treatment course of 6 to 7 weeks, the parotid gland volumes changed up to 34.7%, and the center-of-mass displacement of the 2 parotid glands varied in the range of 0.9 to 8.8 mm. For the primary treatment volume, the cumulative minimum and mean and equivalent uniform doses assessed by the weekly kVCTs were lower than the planned doses by up to 14.9% (P=.14), 2% (P=.39), and 7.3% (P=.05), respectively. The cumulative mean doses were significantly higher than the planned dose for the left parotid (P=.03) and right parotid glands (P=.006). The computation including DIR and dose accumulation was ultrafast (∼45 seconds) with registration accuracy at the subvoxel level. Conclusions: A systematic analysis of anatomic variations in the H&N region and their dosimetric consequences is critical in improving treatment efficacy. Nearly real

  17. The reliability of tablet computers in depicting maxillofacial radiographic landmarks

    This study was performed to evaluate the reliability of the identification of anatomical landmarks in panoramic and lateral cephalometric radiographs on a standard medical grade picture archiving communication system (PACS) monitor and a tablet computer (iPad 5). A total of 1000 radiographs, including 500 panoramic and 500 lateral cephalometric radiographs, were retrieved from the de-identified dataset of the archive of the Section of Oral and Maxillofacial Radiology of the University Of Connecticut School Of Dental Medicine. Major radiographic anatomical landmarks were independently reviewed by two examiners on both displays. The examiners initially reviewed ten panoramic and ten lateral cephalometric radiographs using each imaging system, in order to verify interoperator agreement in landmark identification. The images were scored on a four-point scale reflecting the diagnostic image quality and exposure level of the images. Statistical analysis showed no significant difference between the two displays regarding the visibility and clarity of the landmarks in either the panoramic or cephalometric radiographs. Tablet computers can reliably show anatomical landmarks in panoramic and lateral cephalometric radiographs

  18. The reliability of tablet computers in depicting maxillofacial radiographic landmarks

    Tadinada, Aditya; Mahdian, Mina; Sheth, Sonam; Chandhoke, Taranpreet K.; Gopalakrishna, Aadarsh; Potluri, Anitha; Yadav, Sumit [University of Connecticut School of Dental Medicine, Farmington (United States)

    2015-09-15

    This study was performed to evaluate the reliability of the identification of anatomical landmarks in panoramic and lateral cephalometric radiographs on a standard medical grade picture archiving communication system (PACS) monitor and a tablet computer (iPad 5). A total of 1000 radiographs, including 500 panoramic and 500 lateral cephalometric radiographs, were retrieved from the de-identified dataset of the archive of the Section of Oral and Maxillofacial Radiology of the University Of Connecticut School Of Dental Medicine. Major radiographic anatomical landmarks were independently reviewed by two examiners on both displays. The examiners initially reviewed ten panoramic and ten lateral cephalometric radiographs using each imaging system, in order to verify interoperator agreement in landmark identification. The images were scored on a four-point scale reflecting the diagnostic image quality and exposure level of the images. Statistical analysis showed no significant difference between the two displays regarding the visibility and clarity of the landmarks in either the panoramic or cephalometric radiographs. Tablet computers can reliably show anatomical landmarks in panoramic and lateral cephalometric radiographs.

  19. 3D ultrasound-CT registration of the liver using combined landmark-intensity information

    An important issue in computer-assisted surgery of the liver is a fast and reliable transfer of preoperative resection plans to the intraoperative situation. One problem is to match the planning data, derived from preoperative CT or MR images, with 3D ultrasound images of the liver, acquired during surgery. As the liver deforms significantly in the intraoperative situation non-rigid registration is necessary. This is a particularly challenging task because pre- and intraoperative image data stem from different modalities and ultrasound images are generally very noisy. One way to overcome these problems is to incorporate prior knowledge into the registration process. We propose a method of combining anatomical landmark information with a fast non-parametric intensity registration approach. Mathematically, this leads to a constrained optimization problem. As distance measure we use the normalized gradient field which allows for multimodal image registration. A qualitative and quantitative validation on clinical liver data sets of three different patients has been performed. We used the distance of dense corresponding points on vessel center lines for quantitative validation. The combined landmark and intensity approach improves the mean and percentage of point distances above 3 mm compared to rigid and thin-plate spline registration based only on landmarks. The proposed algorithm offers the possibility to incorporate additional a priori knowledge - in terms of few landmarks - provided by a human expert into a non-rigid registration process. (orig.)

  20. Validation of Setaria (L. P. Beauv Species based on Palyonological and Anatomical Techniques.

    Abdul nazir

    2014-05-01

    Full Text Available In present study external morphology, leaf epidermal anatomy and pollen structureof three species of genus Setaria(Poaceaeviz., S. glauca, S. verticillata and S. viridiswere studied. The major emphasis was on the importance of palyno-anatomical characters used as an aid in plant systematics. Light microscopy (LM and scanning electron microscopy (SEMwere used to study leaf epidermal anatomy and pollen structure.Palyno-anatomical analysis of genus Setaria shows variations within the species. It is stated that the study based on classical and modern approaches is very useful for systematic delimitation of problematic taxa like Setaria.

  1. Prostatome: A combined anatomical and disease based MRI atlas of the prostate

    Rusu, Mirabela; Madabhushi, Anant, E-mail: anant.madabhushi@case.edu [Case Western Reserve University, Cleveland, Ohio 44106 (United States); Bloch, B. Nicolas; Jaffe, Carl C. [Boston University School of Medicine, Boston, Massachusetts 02118 (United States); Genega, Elizabeth M. [Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215 (United States); Lenkinski, Robert E.; Rofsky, Neil M. [UT Southwestern Medical Center, Dallas, Texas 75235 (United States); Feleppa, Ernest [Riverside Research Institute, New York, New York 10038 (United States)

    2014-07-15

    Purpose: In this work, the authors introduce a novel framework, the anatomically constrained registration (AnCoR) scheme and apply it to create a fused anatomic-disease atlas of the prostate which the authors refer to as the prostatome. The prostatome combines a MRI based anatomic and a histology based disease atlas. Statistical imaging atlases allow for the integration of information across multiple scales and imaging modalities into a single canonical representation, in turn enabling a fused anatomical-disease representation which may facilitate the characterization of disease appearance relative to anatomic structures. While statistical atlases have been extensively developed and studied for the brain, approaches that have attempted to combine pathology and imaging data for study of prostate pathology are not extant. This works seeks to address this gap. Methods: The AnCoR framework optimizes a scoring function composed of two surface (prostate and central gland) misalignment measures and one intensity-based similarity term. This ensures the correct mapping of anatomic regions into the atlas, even when regional MRI intensities are inconsistent or highly variable between subjects. The framework allows for creation of an anatomic imaging and a disease atlas, while enabling their fusion into the anatomic imaging-disease atlas. The atlas presented here was constructed using 83 subjects with biopsy confirmed cancer who had pre-operative MRI (collected at two institutions) followed by radical prostatectomy. The imaging atlas results from mapping thein vivo MRI into the canonical space, while the anatomic regions serve as domain constraints. Elastic co-registration MRI and corresponding ex vivo histology provides “ground truth” mapping of cancer extent on in vivo imaging for 23 subjects. Results: AnCoR was evaluated relative to alternative construction strategies that use either MRI intensities or the prostate surface alone for registration. The AnCoR framework

  2. Efficient and Accurate Indoor Localization Using Landmark Graphs

    Gu, F.; Kealy, A.; Khoshelham, K.; Shang, J.

    2016-06-01

    Indoor localization is important for a variety of applications such as location-based services, mobile social networks, and emergency response. Fusing spatial information is an effective way to achieve accurate indoor localization with little or with no need for extra hardware. However, existing indoor localization methods that make use of spatial information are either too computationally expensive or too sensitive to the completeness of landmark detection. In this paper, we solve this problem by using the proposed landmark graph. The landmark graph is a directed graph where nodes are landmarks (e.g., doors, staircases, and turns) and edges are accessible paths with heading information. We compared the proposed method with two common Dead Reckoning (DR)-based methods (namely, Compass + Accelerometer + Landmarks and Gyroscope + Accelerometer + Landmarks) by a series of experiments. Experimental results show that the proposed method can achieve 73% accuracy with a positioning error less than 2.5 meters, which outperforms the other two DR-based methods.

  3. Quantitative assessment of regional left ventricular motion using endocardial landmarks

    C.J. Slager (Cornelis); T.E.H. Hooghoudt (Ton); P.W.J.C. Serruys (Patrick); J.C.H. Schuurbiers (Johan); J.H.C. Reiber (Johan); G.T. Meester (Geert); P.D. Verdouw (Pieter); P.G. Hugenholtz (Paul)

    1986-01-01

    textabstractIn this study the hypothesis is tested that the motion pattern of small anatomic landmarks, recognizable at the left ventricular endocardial border in the contrast angiocardiogram, reflects the motion of the endocardial wall. To verify this, minute metal markers were inserted in the endo

  4. Is it possible to treat the axillary nodes in the same radiation fields covering the breast? - A study to locate the limits of the axillary dissection relative to anatomic landmarks in the tangential fields

    Purpose/Objective: Following breast cancer surgery, radiation of the axillary contents may be considered in lieu of axillary dissection or to reduce potential failure in high risk patients. Tangential breast fields often include a portion of the axilla. This review was undertaken to locate the typical location of the axillary contents in a tangential plane. Surgical clips in the axilla were identified in patients treated with breast radiation and were related to bony landmarks in the vicinity of the tangential fields. The presumption was made that the clips, although often used for hemostasis, were contained in the surgical bed and therefore identified the general location of the axillary nodes. Materials and Methods: 111 patients with surgical clips in the axilla were identified. All patients had undergone 'lumpectomy' and axillary dissection for breast cancer. Simulation films of the breast were analyzed to determine the number and location of axillary clips relative to the tangential fields and bony landmarks. All patients were treated with an SSD technique using custom half-beam blocks designed along midline from the suprasternal notch to the xyphoid process. A 1 to 1.5 cm margin around the breast was targeted. The lateral border was placed at the midaxillary line unless accommodation was required to reduce lung volume or to cover the breast. The treatment table was angled in 22 patients along the divergence of the superior field edge if the lateral field angled into the neck or if a supraclavicular field was used (7 pts). There was no intent to include the axilla in any field. Extent of axillary dissection was not normally dictated in operative reports. Results: Two to 48 clips were identified in the axilla. The median number of clips was 10 (mean 12.4). The median number of dissected nodes was 16 (range 4 to 40). 81 patients had negative nodes. The average number of positive nodes was 3.7 (range 1 to 20). Field lengths ranged from 14 to 21.5 cm, with a median

  5. Optimal landmarks selection and fiducial marker placement for minimal target registration error in image-guided neurosurgery

    Shamir, Reuben R.; Joskowicz, Leo; Shoshan, Yigal

    2009-02-01

    We describe a new framework and method for the optimal selection of anatomical landmarks and optimal placement of fiducial markers in image-guided neurosurgery. The method allows the surgeon to optimally plan the markers locations on routine diagnostic images before preoperative imaging and to intraoperatively select the fiducial markers and the anatomical landmarks that minimize the Target Registration Error (TRE). The optimal fiducial marker configuration selection is performed by the surgeon on the diagnostic image following the target selection based on a visual Estimated TRE (E-TRE) map. The E-TRE map is automatically updated when the surgeon interactively adds and deletes candidate markers and targets. The method takes the guesswork out of the registration process, provides a reliable localization uncertainty error for navigation, and can reduce the localization error without additional imaging and hardware. Our clinical experiments on five patients who underwent brain surgery with a navigation system show that optimizing one marker location and the anatomical landmarks configuration reduces the average TRE from 4.7mm to 3.2mm, with a maximum improvement of 4mm. The reduction of the target registration error has the potential to support safer and more accurate minimally invasive neurosurgical procedures.

  6. Piriformis Fossa – An Anatomical and Orthopedics Consideration

    Lakhwani, O. P.; Mittal, P.S.; D. C. Naik

    2014-01-01

    Introduction: Piriformis fossa is an important anatomical landmark having significant clinical value in orthopedic surgery; but its location and anatomical relationship with surrounding structures are not clearly defined. Hence it is necessary to clearly describe it in respect to anatomical and orthopedic aspect.

  7. Anatomic Mesenchymal Stem Cell-Based Engineered Cartilage Constructs for Biologic Total Joint Replacement.

    Saxena, Vishal; Kim, Minwook; Keah, Niobra M; Neuwirth, Alexander L; Stoeckl, Brendan D; Bickard, Kevin; Restle, David J; Salowe, Rebecca; Wang, Margaret Ye; Steinberg, David R; Mauck, Robert L

    2016-02-01

    constructs. Immunohistochemistry showed abundant collagen type II staining and little collagen type I staining. APS/TEMED crosslinking can be used to produce MSC-seeded HA-based neocartilage and can be used in combination with rapid prototyping techniques to generate anatomic MSC-seeded HA constructs for use in filling large and anatomically complex chondral defects or for biologic joint replacement. PMID:26871863

  8. Cryptic Species or Inadequate Taxonomy? Implementation of 2D Geometric Morphometrics Based on Integumental Organs as Landmarks for Delimitation and Description of Copepod Taxa.

    Karanovic, Tomislav; Djurakic, Marko; Eberhard, Stefan M

    2016-03-01

    Discovery of cryptic species using molecular tools has become common in many animal groups but it is rarely accompanied by morphological revision, creating ongoing problems in taxonomy and conservation. In copepods, cryptic species have been discovered in most groups where fast-evolving molecular markers were employed. In this study at Yeelirrie in Western Australia we investigate a subterranean species complex belonging to the harpacticoid genus Schizopera Sars, 1905, using both the barcoding mitochondrial COI gene and landmark-based two-dimensional geometric morphometrics. Integumental organs (sensilla and pores) are used as landmarks for the first time in any crustacean group. Complete congruence between DNA-based species delimitation and relative position of integumental organs in two independent morphological structures suggests the existence of three distinct evolutionary units. We describe two of them as new species, employing a condensed taxonomic format appropriate for cryptic species. We argue that many supposedly cryptic species might not be cryptic if researchers focus on analyzing morphological structures with multivariate tools that explicitly take into account geometry of the phenotype. A perceived supremacy of molecular methods in detecting cryptic species is in our view a consequence of disparity of investment and unexploited recent advancements in morphometrics among taxonomists. Our study shows that morphometric data alone could be used to find diagnostic morphological traits and gives hope to anyone studying small animals with a hard integument or shell, especially opening the door to assessing fossil diversity and rich museum collections. We expect that simultaneous use of molecular tools with geometry-oriented morphometrics may yield faster formal description of species. Decrypted species in this study are a good example for urgency of formal descriptions, as they display short-range endemism in small groundwater calcrete aquifers in a

  9. Early fetal anatomical sonography.

    Donnelly, Jennifer C

    2012-10-01

    Over the past decade, prenatal screening and diagnosis has moved from the second into the first trimester, with aneuploidy screening becoming both feasible and effective. With vast improvements in ultrasound technology, sonologists can now image the fetus in greater detail at all gestational ages. In the hands of experienced sonographers, anatomic surveys between 11 and 14 weeks can be carried out with good visualisation rates of many structures. It is important to be familiar with the normal development of the embryo and fetus, and to be aware of the major anatomical landmarks whose absence or presence may be deemed normal or abnormal depending on the gestational age. Some structural abnormalities will nearly always be detected, some will never be and some are potentially detectable depending on a number of factors.

  10. MICROSURGICAL LANDMARKS IN MINIMALLY INVASIVE TRANSFORAMINAL LUMBAR INTERBODY FUSION

    Javier Quillo-Olvera

    2015-12-01

    Full Text Available Microsurgical landmarks of the facet joint complex were defined to provide guidance and security within the tubular retractor during transforaminal surgery. A retrospective observational study was performed in segments L4-L5 by the left side approach. Microsurgical relevant photos, anatomical models and drawing were used to expose the suggested landmarks. The MI-TLIF technique has advantages compared with conventional open TLIF technique, however minimally invasive technique implies lack of security for the surgeon due to the lack of defined microanatomical landmarks compared to open spine surgery, and disorientation within the tubular retractor, the reason why to have precise microsurgical references and its recognition within the surgical field provide speed and safety when performing minimally invasive technique.

  11. Anatomical specificity of vascular endothelial growth factor expression in glioblastomas: a voxel-based mapping analysis

    Fan, Xing [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Wang, Yinyan [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Capital Medical University, Department of Neuropathology, Beijing Neurosurgical Institute, Beijing (China); Wang, Kai; Ma, Jun; Li, Shaowu [Capital Medical University, Department of Neuroradiology, Beijing Tiantan Hospital, Beijing (China); Liu, Shuai [Chinese Academy of Medical Sciences and Peking Union Medical College, Departments of Neurosurgery, Peking Union Medical College Hospital, Beijing (China); Liu, Yong [Chinese Academy of Sciences, Brainnetome Center, Institute of Automation, Beijing (China); Jiang, Tao [Capital Medical University, Department of Neurosurgery, Beijing Tiantan Hospital, Beijing (China); Beijing Academy of Critical Illness in Brain, Department of Clinical Oncology, Beijing (China)

    2016-01-15

    The expression of vascular endothelial growth factor (VEGF) is a common genetic alteration in malignant gliomas and contributes to the angiogenesis of tumors. This study aimed to investigate the anatomical specificity of VEGF expression levels in glioblastomas using voxel-based neuroimaging analysis. Clinical information, MR scans, and immunohistochemistry stains of 209 patients with glioblastomas were reviewed. All tumor lesions were segmented manually and subsequently registered to standard brain space. Voxel-based regression analysis was performed to correlate the brain regions of tumor involvement with the level of VEGF expression. Brain regions identified as significantly associated with high or low VEGF expression were preserved following permutation correction. High VEGF expression was detected in 123 (58.9 %) of the 209 patients. Voxel-based statistical analysis demonstrated that high VEGF expression was more likely in tumors located in the left frontal lobe and the right caudate and low VEGF expression was more likely in tumors that occurred in the posterior region of the right lateral ventricle. Voxel-based neuroimaging analysis revealed the anatomic specificity of VEGF expression in glioblastoma, which may further our understanding of genetic heterogeneity during tumor origination. This finding provides primary theoretical support for potential future application of customized antiangiogenic therapy. (orig.)

  12. Anatomical specificity of vascular endothelial growth factor expression in glioblastomas: a voxel-based mapping analysis

    The expression of vascular endothelial growth factor (VEGF) is a common genetic alteration in malignant gliomas and contributes to the angiogenesis of tumors. This study aimed to investigate the anatomical specificity of VEGF expression levels in glioblastomas using voxel-based neuroimaging analysis. Clinical information, MR scans, and immunohistochemistry stains of 209 patients with glioblastomas were reviewed. All tumor lesions were segmented manually and subsequently registered to standard brain space. Voxel-based regression analysis was performed to correlate the brain regions of tumor involvement with the level of VEGF expression. Brain regions identified as significantly associated with high or low VEGF expression were preserved following permutation correction. High VEGF expression was detected in 123 (58.9 %) of the 209 patients. Voxel-based statistical analysis demonstrated that high VEGF expression was more likely in tumors located in the left frontal lobe and the right caudate and low VEGF expression was more likely in tumors that occurred in the posterior region of the right lateral ventricle. Voxel-based neuroimaging analysis revealed the anatomic specificity of VEGF expression in glioblastoma, which may further our understanding of genetic heterogeneity during tumor origination. This finding provides primary theoretical support for potential future application of customized antiangiogenic therapy. (orig.)

  13. Visual SLAM for underwater vehicles using video velocity log and natural landmarks

    Salvi, Joaquim; Petillot, Yvan R.; Thomas, Stephen; Aulinas Masó, Josep M.

    2008-01-01

    A visual SLAM system has been implemented and optimised for real-time deployment on an AUV equipped with calibrated stereo cameras. The system incorporates a novel approach to landmark description in which landmarks are local sub maps that consist of a cloud of 3D points and their associated SIFT/SURF descriptors. Landmarks are also sparsely distributed which simplifies and accelerates data association and map updates. In addition to landmark-based localisation the system utilises visual odom...

  14. Construction and Biomechanical Properties of PolyAxial Self-Locking Anatomical Plate Based on the Geometry of Distal Tibia

    Weiguo Liang; Weixiong Ye; Dongping Ye; Ziqiang Zhou; Zhiguang Chen; Aiguo Li; Zong-Han Xie; Lihai Zhang; Jiake Xu

    2014-01-01

    In order to provide scientific and empirical evidence for the clinical application of the polyaxial self-locking anatomical plate, 80 human tibias from healthy adults were scanned by spiral CT and their three-dimensional images were reconstructed using the surface shaded display (SSD) method. Firstly, based on the geometric data of distal tibia, a polyaxial self-locking anatomical plate for distal tibia was designed and constructed. Biomechanical tests were then performed by applying axial lo...

  15. Sparse decomposition and modeling of anatomical shape variation

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte;

    2007-01-01

    counterparts if constructed carefully. In most medical applications, models are required to have both good statistical performance and a relevant clinical interpretation to be of value. Morphometry of the corpus callosum is one illustrative example. This paper presents a method for relating spatial features to...... anatomical variation related to clinical outcome. In the present application, landmark-based shape data of the corpus callosum is analyzed in relation to age, gender, and clinical tests of walking speed and verbal fluency. To put the data-driven sparse principal component method into perspective, we consider...

  16. Sparse Decomposition and Modeling of Anatomical Shape Variation

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte;

    2007-01-01

    counterparts if constructed carefully. In most medical applications, models are required to have both good statistical performance and a relevant clinical interpretation to be of value. Morphometry of the corpus callosum is one illustrative example. This paper presents a method for relating spatial features to...... anatomical variation related to clinical outcome. In the present application, landmark-based shape data of the corpus callosum is analyzed in relation to age, gender, and clinical tests of walking speed and verbal fluency. To put the data-driven sparse principal component method into perspective, we consider...

  17. 3D facial landmarks: Inter-operator variability of manual annotation

    Fagertun, Jens; Harder, Stine; Rosengren, Anders;

    2014-01-01

    .g. the research fields of orthodontics and cephalometrics. We present a full facial 3D annotation procedure and a sparse set of manually annotated landmarks, in effort to reduce operator time and minimize the variance. Method Facial scans from 36 voluntary unrelated blood donors from the Danish Blood...... landmarks in order to construct a dense correspondence map of the 3D scans with a minimum point variance. Results The anatomical landmarks of the eye were associated with the lowest variance, particularly the center of the pupils. Whereas points of the jaw and eyebrows have the highest variation. We see......Background Manual annotation of landmarks is a known source of variance, which exist in all fields of medical imaging, influencing the accuracy and interpretation of the results. However, the variability of human facial landmarks is only sparsely addressed in the current literature as opposed to e...

  18. A New Anatomically Based Nomenclature for the Roots and Root Canals—Part 1: Maxillary Molars

    Jojo Kottoor

    2012-01-01

    Full Text Available Numerous terminologies have been employed in the dental literature to describe the roots and root canal systems of maxillary molars. This multiplicity in naming of roots and canals makes the reader susceptible to misinterpretation and confusion. No consensus thus far has been arrived at for defining the names of roots and root canals in maxillary molars, including their various morphological aberrations. The anatomical relation of roots and their root canals were identified and were subsequently named based on definite sets of criteria. A new method for identification and naming of roots and root canal anatomy in maxillary molars, based on their root and canal relationship, was formulated and is presented in this paper. The nomenclature makes certain essential modifications to the traditional approach to accommodate naming of the various aberrations presented in the maxillary molars. A simple, yet extensive, nomenclature system has been proposed that appropriately names the internal and external morphology of maxillary molars.

  19. DETEKSI LANDMARK CITRA WAJAH DENGAN EXTRAKSI FITUR GABOR ANALISA FUZZY

    Resmana Lim

    2003-01-01

    Full Text Available This paper proposes a method that automatically finds human faces as well as its landmark points in color images based on a fuzzy analysis. The proposed approach first uses color information to detect face candidate regions and then uses a fuzzy analysis of the color, shape, symmetry and interior facial features. A deformable Gabor wavelet graph matching is used to locate the facial landmark points describing the face. The latter allows for size and orientation variation since the search for landmark points allows for affine transformations as well as local deformations of the Gabor wavelet graph. The search is performed using a genetic algorithm that is essential because it effectively searches the solution space. Results based on the proposed method are included to verify the effectiveness of the proposed approach. Abstract in Bahasa Indonesia : Paper ini mengusulkan sebuah metode deteksi wajah beserta dengan titik landmarknya pada citra berwarna menggunakan analisa fuzzy. Proses awal menggunakan informasi warna kulit untuk menseleksi calon-calon obyek lantas dilanjukan dengan analisa fuzzy terhadap warna, bentuk, simetri dan fitur/landmark wajah. Proses lokalisasi landmark wajah menggunakan Gabor wavelet graph matching dengan memaksimalkan kemiripan antara landmark wajah model dengan obyek inputan. Proses maksimalisasi kemiripan ini menggunakan algoritma genetika. Hasil-hasil percobaan ditampilkan untuk memberikan gambaran keberhasilan dari metode yang diusulkan. Kata kunci: lokalisasi landmark wajah, analisa fuzzy, graph matching, algoritma genetika, Gabor wavelet.

  20. Describing head shapes of white stem borers (Schirpophaga innotata Walker that are able to survive on different rice types using Landmark based geometric morphometrics

    Queenilyn B. Albutra

    2012-06-01

    Full Text Available Rice stem borers are considered as the most serious insect pest of rice in Asia. It infects itsplant host by burrowing into the stem using its mandible. However, apart from the mandible, the head ofrice stem borers is also associated in the incursion process since it facilitates the entry of larvae to the riceplant. Differences in the head capsules have a direct effect on the ability of the insects to ingest hardfoods rapidly. Different rice varieties in the Philippines serve as plant host for this pest and infestationoccurred in different geographical location. Variations in habitat and plant host were thought to generateenvironmental variation in morphometric traits and host adapted herbivore phenotype respectively.Landmark based geometric morphometric analysis was used to assess the hypothesis that the head shapeof white stem borer differ between populations with respect to different rice varieties and geographicallocation where it was obtained. Relative warp analysis showed variation in the head shape betweendifferent white stem borer (Schirpophaga innotata Walker populations infesting different varieties of rice.Non-significant head shape variations were obtained between geographically separated populations. Theseresults indicate that the rice host varieties play an important role in the selection of individuals that areable to counteract the resistance factors in plants.

  1. Visual EKF-SLAM from Heterogeneous Landmarks

    Esparza-Jiménez, Jorge Othón; Devy, Michel; Gordillo, José L.

    2016-01-01

    Many applications require the localization of a moving object, e.g., a robot, using sensory data acquired from embedded devices. Simultaneous localization and mapping from vision performs both the spatial and temporal fusion of these data on a map when a camera moves in an unknown environment. Such a SLAM process executes two interleaved functions: the front-end detects and tracks features from images, while the back-end interprets features as landmark observations and estimates both the landmarks and the robot positions with respect to a selected reference frame. This paper describes a complete visual SLAM solution, combining both point and line landmarks on a single map. The proposed method has an impact on both the back-end and the front-end. The contributions comprehend the use of heterogeneous landmark-based EKF-SLAM (the management of a map composed of both point and line landmarks); from this perspective, the comparison between landmark parametrizations and the evaluation of how the heterogeneity improves the accuracy on the camera localization, the development of a front-end active-search process for linear landmarks integrated into SLAM and the experimentation methodology. PMID:27070602

  2. WE-D-9A-02: Automated Landmark-Guided CT to Cone-Beam CT Deformable Image Registration

    Purpose: The anatomical changes that occur between the simulation CT and daily cone-beam CT (CBCT) are investigated using an automated landmark-guided deformable image registration (LDIR) algorithm with simultaneous intensity correction. LDIR was designed to be accurate in the presence of tissue intensity mismatch and heavy noise contamination. Method: An auto-landmark generation algorithm was used in conjunction with a local small volume (LSV) gradient matching search engine to map corresponding landmarks between the CBCT and planning CT. The LSVs offsets were used to perform an initial deformation, generate landmarks, and correct local intensity mismatch. The landmarks act as stabilizing controlpoints in the Demons objective function. The accuracy of the LDIR algorithm was evaluated on one synthetic case with ground truth and data of ten head and neck cancer patients. The deformation vector field (DVF) accuracy was accessed using a synthetic case. The Root mean square error of the 3D canny edge (RMSECE), mutual information (MI), and feature similarity index metric (FSIM) were used to access the accuracy of LDIR on the patient data. The quality of the corresponding deformed contours was verified by an attending physician. Results: The resulting 90 percentile DVF error for the synthetic case was within 5.63mm for the original demons algorithm, 2.84mm for intensity correction alone, 2.45mm using controlpoints without intensity correction, and 1.48 mm for the LDIR algorithm. For the five patients the mean RMSECE of the original CT, Demons deformed CT, intensity corrected Demons CT, control-point stabilized deformed CT, and LDIR CT was 0.24, 0.26, 0.20, 0.20, and 0.16 respectively. Conclusion: LDIR is accurate in the presence of multimodal intensity mismatch and CBCT noise contamination. Since LDIR is GPU based it can be implemented with minimal additional strain on clinical resources. This project has been supported by a CPRIT individual investigator award RP11032

  3. Sub-micrometer anatomical models of the sarcolemma of cardiac myocytes based on confocal imaging.

    Sachse, Frank B; Savio-Galimberti, Eleonora; Goldhaber, Joshua I; Bridge, John H B

    2008-01-01

    We describe an approach to develop anatomical models of cardiac cells. The approach is based on confocal imaging of living ventricular myocytes with submicrometer resolution, digital image processing of three-dimensional stacks with high data volume, and generation of dense triangular surface meshes representing the sarcolemma including the transverse tubular system. The image processing includes methods for deconvolution, filtering and segmentation. We introduce and visualize models of the sarcolemma of whole ventricular myocytes and single transversal tubules. These models can be applied for computational studies of cell and sub-cellular physical behavior and physiology, in particular cell signaling. Furthermore, the approach is applicable for studying effects of cardiac development, aging and diseases, which are associated with changes of cell anatomy and protein distributions. PMID:18229702

  4. Landmark Image Retrieval Using Visual Synonyms

    Gavves, E.; Snoek, C.G.M.

    2010-01-01

    In this paper, we consider the incoherence problem of the visual words in bag-of-words vocabularies. Different from existing work, which performs assignment of words based solely on closeness in descriptor space, we focus on identifying pairs of independent, distant words - the visual synonyms - that are still likely to host image patches with similar appearance. To study this problems we focus on landmark images, where we can examine whether image geometry is an appropriate vehicle for detec...

  5. The variability in the external rotation axis of the distal femur: an MRI-based anatomical study.

    Jones, Carl; Nawaz, Zuhair; Hassan, Abdel; White, Simon; Khaleel, Arshad

    2016-02-01

    Commonly used total knee arthroplasty (TKA) systems utilising measured resection techniques default to 5°-7° valgus for the distal cut relative to the anatomical axis and 3° external rotation of the femoral component relative to posterior condylar axis (PCA). Rotational errors of the femoral component are associated with pain, patella maltracking and a poorer outcome. We analysed MRI scans from patients undergoing TKA using patient-specific instrumentation to assess coronal and rotational alignment from landmarks identified on the scans. One hundred and eight scans in 59 males and 49 females were studied with age range 35-93 years (mean 67.9 years). We found 91 % of patients had a femoral valgus angle between 5° and 7° (mean angles 5.9°), while only 24 % had an external rotation angle between 2.5° and 3.5° relative to PCA. There was no statistical significance in rotation between males and females although outliers tended to be female. Mean Whiteside's angle was 92.9° (87.8-98). This study highlights the variations in external rotation between patients undergoing TKA using the PCA as a reference for rotation. This may be a contributing factor in implant malalignment and patient dissatisfaction. PMID:26530410

  6. Endoscopic expand transnasal approach to the suprasellar region :anatomical study and clinical considerations

    LU Xiao-jie; CHEN Kai-lai; WANG Qin; JI Wei-yang; LI Bing; SUN Ji-yong; LI Jiang-an

    2009-01-01

    Backgroud The expanded endonasal approach (EEA) is used sparingly by surgeons for resection of lesions in the ventrocranial base. Herein, we examined the anatomy of the ventrocranial base by endoscopy and comment on the use of EEA in clinical practice.Methods Twenty artery-injected adult cadaveric heads were studied under surgical conditions using the endoscopic EEA. The extent of the surgical exposure, the endoscopic anatomic view and the maneuverability of surgical instruments about the suprasellar region were studied by the endoscopic EEA.Results The EEA by endoscope can reach the suprasellar region. In this approach, the optocarotid recess, supra and infra-optic chiasm interspace, the ophthalmic artery and others were important anatomical landmarks for identification of the suprasellar region.Conclusions The endoscopic EEA can be used to remove many types of lesions in the ventrocranial base. The microanatorny observed using the endoscope provides important anatomical information on the suprasellar region for neurosurgeons.

  7. Global and local spatial landmarks: their role during foraging by Columbian ground squirrels (Spermophilus columbianus).

    Vlasak, Anna N

    2006-01-01

    Locating food and refuge is essential for an animal's survival. However, little is known how mammals navigate under natural conditions and cope with given environmental constraints. In a series of six experiments, I investigated landmark-based navigation in free-ranging Columbian ground squirrels (Spermophilus columbianus). Squirrels were trained individually to find a baited platform within an array of nine identical platforms and artificial landmarks set up on their territories. After animals learned the location of the food platform in the array, the position of the latter with respect to local artificial, local natural, and global landmarks was manipulated, and the animal's ability to find the food platform was tested. When only positions of local artificial landmarks were changed, squirrels located food with high accuracy. When the location of the array relative to global landmarks was altered, food-finding accuracy decreased but remained significant. In the absence of known global landmarks, the presence of a familiar route and natural local landmarks resulted in significant but not highly accurate performance. Squirrels likely relied on multiple types of cues when orienting towards a food platform. Local landmarks were used only as a secondary mechanism of navigation, and were not attended to when a familiar route and known global landmarks were present. This study provided insights into landmark use by a wild mammal in a natural situation, and it demonstrated that an array of platforms can be employed to investigate landmark-based navigation under such conditions. PMID:16163480

  8. DETEKSI LANDMARK CITRA WAJAH DENGAN EXTRAKSI FITUR GABOR ANALISA FUZZY

    Resmana Lim

    2003-01-01

    This paper proposes a method that automatically finds human faces as well as its landmark points in color images based on a fuzzy analysis. The proposed approach first uses color information to detect face candidate regions and then uses a fuzzy analysis of the color, shape, symmetry and interior facial features. A deformable Gabor wavelet graph matching is used to locate the facial landmark points describing the face. The latter allows for size and orientation variation since the search for ...

  9. Selecting landmarks in novel environments.

    Miller, Jared; Carlson, Laura

    2011-02-01

    People use salient landmarks when learning a route through a novel environment. However, it is not clear what makes a given landmark salient. In two experiments, subjects learned a route through a virtual museum, performed a recognition memory test for objects in the museum, and provided spatial descriptions and drew maps of the learned route. Objects with strong perceptual features occurred at decision points or at non-decision points along the route. Objects with both of these features were recognized faster and were included more often in the maps and written directions. When these features were separated, perceptual features maintained a strong influence on the recognition task, but had no influence on the spatial tasks, which were influenced only by spatial features. These findings challenge the idea that either a recognition task or descriptive task alone provides a complete account of landmark representation. PMID:21327344

  10. Support vector machine-based classification of Alzheimer's disease from whole-brain anatomical MRI

    We present and evaluate a new automated method based on support vector machine (SVM) classification of whole-brain anatomical magnetic resonance imaging to discriminate between patients with Alzheimer's disease (AD) and elderly control subjects. We studied 16 patients with AD [mean age ± standard deviation (SD)=74.1 ±5.2 years, mini-mental score examination (MMSE) = 23.1 ± 2.9] and 22 elderly controls (72.3±5.0 years, MMSE=28.5± 1.3). Three-dimensional T1-weighted MR images of each subject were automatically parcellated into regions of interest (ROIs). Based upon the characteristics of gray matter extracted from each ROI, we used an SVM algorithm to classify the subjects and statistical procedures based on bootstrap resampling to ensure the robustness of the results. We obtained 94.5% mean correct classification for AD and control subjects (mean specificity, 96.6%; mean sensitivity, 91.5%). Our method has the potential in distinguishing patients with AD from elderly controls and therefore may help in the early diagnosis of AD. (orig.)

  11. CFD simulation of aerosol deposition in an anatomically based human large-medium airway model.

    Ma, Baoshun; Lutchen, Kenneth R

    2009-02-01

    Quantitative data on aerosol deposition in the human respiratory tract are useful for understanding the causes of certain lung diseases and for designing efficient drug delivery systems via inhalation. In this study, aerosol deposition in a 3D anatomically based human large-medium airway model was simulated using computational fluid dynamics (CFD). The model extended from mouth to generation 10 and included two-thirds of the airways obtained by multi-detector row computed tomography (MDCT) imaging on normal healthy human subjects. Steady oral inhalation (15, 30, and 60 L/min) and aerosol (1-30 micrometer) deposition were computed by CFD using the realizable k-epsilon turbulence model. Based on the mean turbulence flow field, the computed extrathoracic deposition, ratio of left to right lung deposition, and deposition efficiency at each generation compared favorably with existing in vivo and in vitro experiments. The significant deposition in the large-medium airway model showed that the total tracheobronchial deposition is dominated by the large-medium airways for micrometer-sized aerosol particles. These quantitative data and the methods developed in this study provided valuable means toward subject-specific modeling of aerosol deposition in the human lung based on realistic lung geometry. PMID:19082892

  12. Segmentation of anatomical branching structures based on texture features and conditional random field

    Nuzhnaya, Tatyana; Bakic, Predrag; Kontos, Despina; Megalooikonomou, Vasileios; Ling, Haibin

    2012-02-01

    This work is a part of our ongoing study aimed at understanding a relation between the topology of anatomical branching structures with the underlying image texture. Morphological variability of the breast ductal network is associated with subsequent development of abnormalities in patients with nipple discharge such as papilloma, breast cancer and atypia. In this work, we investigate complex dependence among ductal components to perform segmentation, the first step for analyzing topology of ductal lobes. Our automated framework is based on incorporating a conditional random field with texture descriptors of skewness, coarseness, contrast, energy and fractal dimension. These features are selected to capture the architectural variability of the enhanced ducts by encoding spatial variations between pixel patches in galactographic image. The segmentation algorithm was applied to a dataset of 20 x-ray galactograms obtained at the Hospital of the University of Pennsylvania. We compared the performance of the proposed approach with fully and semi automated segmentation algorithms based on neural network classification, fuzzy-connectedness, vesselness filter and graph cuts. Global consistency error and confusion matrix analysis were used as accuracy measurements. For the proposed approach, the true positive rate was higher and the false negative rate was significantly lower compared to other fully automated methods. This indicates that segmentation based on CRF incorporated with texture descriptors has potential to efficiently support the analysis of complex topology of the ducts and aid in development of realistic breast anatomy phantoms.

  13. Landmarks or panoramas: what do navigating ants attend to for guidance?

    Beugnon Guy

    2011-08-01

    Full Text Available Abstract Background Insects are known to rely on terrestrial landmarks for navigation. Landmarks are used to chart a route or pinpoint a goal. The distant panorama, however, is often thought not to guide navigation directly during a familiar journey, but to act as a contextual cue that primes the correct memory of the landmarks. Results We provided Melophorus bagoti ants with a huge artificial landmark located right near the nest entrance to find out whether navigating ants focus on such a prominent visual landmark for homing guidance. When the landmark was displaced by small or large distances, ant routes were affected differently. Certain behaviours appeared inconsistent with the hypothesis that guidance was based on the landmark only. Instead, comparisons of panoramic images recorded on the field, encompassing both landmark and distal panorama, could explain most aspects of the ant behaviours. Conclusion Ants navigating along a familiar route do not focus on obvious landmarks or filter out distal panoramic cues, but appear to be guided by cues covering a large area of their panoramic visual field, including both landmarks and distal panorama. Using panoramic views seems an appropriate strategy to cope with the complexity of natural scenes and the poor resolution of insects' eyes. The ability to isolate landmarks from the rest of a scene may be beyond the capacity of animals that do not possess a dedicated object-perception visual stream like primates.

  14. Anatomía Artística: Bases Anatómicas del Retrato Escultórico Realista

    Jiménez Mateos, Miguel Ángel

    1999-01-01

    El saber sobre la estructura del organismo humano ha ido creciendo siguiendo las bases de cualquier otra ciencia. La curiosidad de los propios humanos los condujo a observar los organismos y a intentar indagar en ellos más allá de los límites de la observación superficial, penetrando en su interior dividiendo sus partes. “Anatomía: cortar repetidas veces”. La Anatomía analiza las relaciones causales que tanto la estructura como la función guardan entre sí, así como las modificaciones de índol...

  15. Quantitative modeling of the accuracy in registering preoperative patient-specific anatomic models into left atrial cardiac ablation procedures

    Rettmann, Maryam E., E-mail: rettmann.maryam@mayo.edu; Holmes, David R.; Camp, Jon J.; Cameron, Bruce M.; Robb, Richard A. [Biomedical Imaging Resource, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States); Kwartowitz, David M. [Department of Bioengineering, Clemson University, Clemson, South Carolina 29634 (United States); Gunawan, Mia [Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington D.C. 20057 (United States); Johnson, Susan B.; Packer, Douglas L. [Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905 (United States); Dalegrave, Charles [Clinical Cardiac Electrophysiology, Cardiology Division Hospital Sao Paulo, Federal University of Sao Paulo, 04024-002 Brazil (Brazil); Kolasa, Mark W. [David Grant Medical Center, Fairfield, California 94535 (United States)

    2014-02-15

    Purpose: In cardiac ablation therapy, accurate anatomic guidance is necessary to create effective tissue lesions for elimination of left atrial fibrillation. While fluoroscopy, ultrasound, and electroanatomic maps are important guidance tools, they lack information regarding detailed patient anatomy which can be obtained from high resolution imaging techniques. For this reason, there has been significant effort in incorporating detailed, patient-specific models generated from preoperative imaging datasets into the procedure. Both clinical and animal studies have investigated registration and targeting accuracy when using preoperative models; however, the effect of various error sources on registration accuracy has not been quantitatively evaluated. Methods: Data from phantom, canine, and patient studies are used to model and evaluate registration accuracy. In the phantom studies, data are collected using a magnetically tracked catheter on a static phantom model. Monte Carlo simulation studies were run to evaluate both baseline errors as well as the effect of different sources of error that would be present in a dynamicin vivo setting. Error is simulated by varying the variance parameters on the landmark fiducial, physical target, and surface point locations in the phantom simulation studies. In vivo validation studies were undertaken in six canines in which metal clips were placed in the left atrium to serve as ground truth points. A small clinical evaluation was completed in three patients. Landmark-based and combined landmark and surface-based registration algorithms were evaluated in all studies. In the phantom and canine studies, both target registration error and point-to-surface error are used to assess accuracy. In the patient studies, no ground truth is available and registration accuracy is quantified using point-to-surface error only. Results: The phantom simulation studies demonstrated that combined landmark and surface-based registration improved

  16. Quantitative modeling of the accuracy in registering preoperative patient-specific anatomic models into left atrial cardiac ablation procedures

    Purpose: In cardiac ablation therapy, accurate anatomic guidance is necessary to create effective tissue lesions for elimination of left atrial fibrillation. While fluoroscopy, ultrasound, and electroanatomic maps are important guidance tools, they lack information regarding detailed patient anatomy which can be obtained from high resolution imaging techniques. For this reason, there has been significant effort in incorporating detailed, patient-specific models generated from preoperative imaging datasets into the procedure. Both clinical and animal studies have investigated registration and targeting accuracy when using preoperative models; however, the effect of various error sources on registration accuracy has not been quantitatively evaluated. Methods: Data from phantom, canine, and patient studies are used to model and evaluate registration accuracy. In the phantom studies, data are collected using a magnetically tracked catheter on a static phantom model. Monte Carlo simulation studies were run to evaluate both baseline errors as well as the effect of different sources of error that would be present in a dynamicin vivo setting. Error is simulated by varying the variance parameters on the landmark fiducial, physical target, and surface point locations in the phantom simulation studies. In vivo validation studies were undertaken in six canines in which metal clips were placed in the left atrium to serve as ground truth points. A small clinical evaluation was completed in three patients. Landmark-based and combined landmark and surface-based registration algorithms were evaluated in all studies. In the phantom and canine studies, both target registration error and point-to-surface error are used to assess accuracy. In the patient studies, no ground truth is available and registration accuracy is quantified using point-to-surface error only. Results: The phantom simulation studies demonstrated that combined landmark and surface-based registration improved

  17. Phylogenetic and phytogeographical relationships in Maloideae (Rosaceae) based on morphological and anatomical characters

    Aldasoro, J.J.; Aedo, C.; Navarro, C.

    2005-01-01

    Phylogenetic relationships among 24 genera of Rosaceae subfam. Maloideae and Spiraeoideae are explored by means of a cladistic analysis; 16 morphological and anatomical characters were included in the analysis. Published suprageneric classifications and characters used in these classifications are b

  18. The Great American Landmarks Adventure.

    Weeks, Kay

    This profusely illustrated booklet, written primarly for school children, includes drawings and descriptions of 43 of the National Historic Landmarks located in the United States. The accounts move chronologically from prehistoric cave paintings through the moon rocks collected by the Apollo astronauts in 1969. Most of the drawings represent the…

  19. A review of terminology for equine juvenile osteochondral conditions (JOCC) based on anatomical and functional considerations.

    Denoix, J-M; Jeffcott, L B; McIlwraith, C W; van Weeren, P R

    2013-07-01

    This manuscript describes a new classification of the various joint-related lesions that can be seen in the young, growing horse based on their anatomical and functional aetiopathogenesis. Juvenile osteochondral conditions (JOCC) is a term that brings together specific disorders according to their location in the joint and their biomechanical origin. When a biomechanical insult affects the process of endochondral ossification different types of osteochondrosis (OC) lesions may occur, including osteochondral fragmentation of the articular surface or of the periarticular margins, or the formation of juvenile subchondral bone cysts. In severe cases, osteochondral collapse of the articular surface or the epiphysis or even an entire small bone may occur. Tension on ligament attachments may cause avulsion fractures of epiphyseal (or metaphyseal) ossifying bone, which are classified as JOCC, but do not result from a disturbance of the process of endochondral ossification and are not therefore classified as a form of OC. The same applies to 'physitis' which can result from damage to the physeal growth plate. PMID:23683533

  20. PACS-based interface for 3D anatomical structure visualization and surgical planning

    Koehl, Christophe; Soler, Luc; Marescaux, Jacques

    2002-05-01

    The interpretation of radiological image is routine but it remains a rather difficult task for physicians. It requires complex mental processes, that permit translation from 2D slices into 3D localization and volume determination of visible diseases. An easier and more extensive visualization and exploitation of medical images can be reached through the use of computer-based systems that provide real help from patient admission to post-operative followup. In this way, we have developed a 3D visualization interface linked to a PACS database that allows manipulation and interaction on virtual organs delineated from CT-scan or MRI. This software provides the 3D real-time surface rendering of anatomical structures, an accurate evaluation of volumes and distances and the improvement of radiological image analysis and exam annotation through a negatoscope tool. It also provides a tool for surgical planning allowing the positioning of an interactive laparoscopic instrument and the organ resection. The software system could revolutionize the field of computerized imaging technology. Indeed, it provides a handy and portable tool for pre-operative and intra-operative analysis of anatomy and pathology in various medical fields. This constitutes the first step of the future development of augmented reality and surgical simulation systems.

  1. Anatomical bases for the radiological delineation of lymph node areas. Major collecting trunks, head and neck

    Cancer spreads locally through direct infiltration into soft tissues or at distance by invading vascular structures, then migrating through the lymphatic or blood flow. Although cancer cells carried in the blood can end in virtually any corner of the body, lymphatic migration is usually stepwise, through successive nodal stops, which can temporarily delay further progression. In radiotherapy, irradiation of lymphatic paths relevant to the localisation of the primary has been common practice for decades. Similarly, excision of cancer is often completed by lymphatic dissection. Both in radiotherapy and in surgery, advanced knowledge of the lymphatic pathways relevant to any tumor location is an important information for treatment preparation and execution. This first part describes the major collecting trunks of the lymphatic system and then the lymphatics of the head and neck providing anatomical bases for the radiological delineation of lymph node areas in the cervical region, it adds to the existing nomenclature of six nodal levels (I-VI), three new areas listed as parotid, buccal and external jugular levels

  2. Anatomic feature-based registration for patient set-up in head and neck cancer radiotherapy

    Modern radiotherapy equipment is capable of delivering high precision conformal dose distributions relative to isocentre. One of the barriers to precise treatments is accurate patient re-positioning before each fraction of treatment. At Massachusetts General Hospital, we perform daily patient alignment using radiographs, which are captured by flat panel imaging devices and sent to an analysis program. A trained therapist manually selects anatomically significant features in the skeleton, and couch movement is computed based on the image coordinates of the features. The current procedure takes about 5 to 10 min and significantly affects the efficiency requirement in a busy clinic. This work presents our effort to develop an improved, semi-automatic procedure that uses the manually selected features from the first treatment fraction to automatically locate the same features on the second and subsequent fractions. An implementation of this semi-automatic procedure is currently in clinical use for head and neck tumour sites. Radiographs collected from 510 patient set-ups were used to test this algorithm. A mean difference of 1.5 mm between manual and automatic localization of individual features and a mean difference of 0.8 mm for overall set-up were seen

  3. Patient Safety Curriculum for Anatomic Pathology Trainees: Recommendations Based on Institutional Experience.

    Samulski, Teresa D; Montone, Kathleen; LiVolsi, Virginia; Patel, Ketan; Baloch, Zubair

    2016-03-01

    Because of the unique systems and skills involved in patient care by the pathologist, it is challenging to design and implement relevant training in patient safety for pathology trainees. We propose a patient safety curriculum for anatomic pathology (AP) residents based on our institutional experience. The Hospital of the University of the Pennsylvania employs a self-reporting safety database. The occurrences from July 2013 to June 2015 recorded in this system that involved the division of AP were reviewed and cataloged as preanalytic, analytic, and postanalytic. The distribution of these occurrences was then used to create a framework for curriculum development in AP. We identified areas in which trainees are involved in the identification and prevention of common patient safety errors that occur in our AP department. Using these data-proven target areas, and employing current Accreditation Council for Graduate Medical Education recommendations and patient safety literature, a strategy for delivering relevant patient safety training is proposed. Teaching patient safety to pathology trainees is a challenging, yet necessary, component of AP training programs. By analyzing the patient safety errors that occur in the AP department, relevant and actionable training can be developed. This provides quality professional development and improves overall performance as trainees are integrated into laboratory systems. PMID:26849817

  4. ANATOMICAL PRINCIPLES BEHIND PRESERVATION OF LARYNGEAL NERVES DURING THYROIDECTOMY

    O. Fabian

    2011-08-01

    Full Text Available This paper presents the anatomical principles behind preservation of inferior laryngeal nerve and of the external branch of superior laryngeal nerve during thyroidectomy. The embryological development of thyroid and recurrent laryngeal nerves explains the constant relationship between Zuckerkandl’s tuberculum and the recurrent laryngeal nerve, while anomalies in development of the aortic arches explain the presence of rare anatomical variants, with a high risk of nerve injury, of non-recurrent course of the inferior laryngeal nerve. Good knowledge of the relationship between the external branch of superior laryngeal nerve and the superior thyroid artery makes possible to avoid transection of this branch during ligature around superior thyroid artery and vein. Anatomical landmarks used to identify the recurrent laryngeal nerve (tracheo-oesophageal sulcus, the cross-over with the inferior thyroid artery, Berry’s ligament, Zuckerkandl’s tuberculum and variations in the extra-laryngeal branching of the nerve are discussed based on data from the literature. The anatomical variants when the inferior laryngeal nerve doesn’t have a recurrent course are also discussed

  5. All that Glitters is not Gold: Using Landmarks for Reward Shaping in FPG

    Buffet, Olivier; Hoffmann, Joerg

    2010-01-01

    Landmarks are facts that must be true at some point in any plan. It has recently been proposed in classical planning to use landmarks for the automatic generation of heuristic functions. We herein apply this idea in probabilistic planning. We focus on the FPG tool, which derives a factored policy based on learning from samples into the state space. The rationale is that FPG's performance can be improved significantly by a trivial heuristic that counts the number of false goals; landmarks prov...

  6. Alignment of CT images of skull dysmorphology using anatomy-based perpendicular axes

    Yoo, Sun K [Department of Medical Engineering, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Yong O [Department of Plastic and Reconstructive Surgery, Yonsei University College of Medicine, Institute of Human Tissue Restoration, Seoul (Korea, Republic of); Kim, Hee-Joung [Department of Diagnostic Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Nam H [Department of Medical Engineering, Yonsei University College of Medicine, Seoul (Korea, Republic of); Jang, Young Beom [Department of Information and Telecommunication Engineering, Sangmyung University, Cheoan (Korea, Republic of); Kim, Kee-Deog [Department of Oral and Maxillofacial Radiology, Yonsei University College of Dentistry, Seoul (Korea, Republic of); Lee, Hye-Yeon [Department of Anatomy, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2003-08-21

    Rigid body registration of 3D CT scans, based on manual identification of homologous landmarks, is useful for the visual analysis of skull dysmorphology. In this paper, a robust and simple alignment method was proposed to allow for the comparison of skull morphologies, within and between individuals with craniofacial anomalies, based on 3D CT scans, and the minimum number of anatomical landmarks, under rigidity and uniqueness constraints. Three perpendicular axes, extracted from anatomical landmarks, define the absolute coordinate system, through a rigid body transformation, to align multiple CT images for different patients and acquisition times. The accuracy of the alignment method depends on the accuracy of the localized landmarks and target points. The numerical simulation generalizes the accuracy requirements of the alignment method. Experiments using a human dried skull specimen, and ten sets of skull CT images (the pre- and post-operative CT scans of four plagiocephaly, and one fibrous dysplasia patients), demonstrated the feasibility of the technique in clinical practice.

  7. Alignment of CT images of skull dysmorphology using anatomy-based perpendicular axes

    Rigid body registration of 3D CT scans, based on manual identification of homologous landmarks, is useful for the visual analysis of skull dysmorphology. In this paper, a robust and simple alignment method was proposed to allow for the comparison of skull morphologies, within and between individuals with craniofacial anomalies, based on 3D CT scans, and the minimum number of anatomical landmarks, under rigidity and uniqueness constraints. Three perpendicular axes, extracted from anatomical landmarks, define the absolute coordinate system, through a rigid body transformation, to align multiple CT images for different patients and acquisition times. The accuracy of the alignment method depends on the accuracy of the localized landmarks and target points. The numerical simulation generalizes the accuracy requirements of the alignment method. Experiments using a human dried skull specimen, and ten sets of skull CT images (the pre- and post-operative CT scans of four plagiocephaly, and one fibrous dysplasia patients), demonstrated the feasibility of the technique in clinical practice

  8. Memory consolidation of landmarks in good navigators.

    Janzen, Gabriele; Jansen, Clemens; van Turennout, Miranda

    2008-01-01

    Landmarks play an important role in successful navigation. To successfully find your way around an environment, navigationally relevant information needs to be stored and become available at later moments in time. Evidence from functional magnetic resonance imaging (fMRI) studies shows that the human parahippocampal gyrus encodes the navigational relevance of landmarks. In the present event-related fMRI experiment, we investigated memory consolidation of navigationally relevant landmarks in the medial temporal lobe after route learning. Sixteen right-handed volunteers viewed two film sequences through a virtual museum with objects placed at locations relevant (decision points) or irrelevant (nondecision points) for navigation. To investigate consolidation effects, one film sequence was seen in the evening before scanning, the other one was seen the following morning, directly before scanning. Event-related fMRI data were acquired during an object recognition task. Participants decided whether they had seen the objects in the previously shown films. After scanning, participants answered standardized questions about their navigational skills, and were divided into groups of good and bad navigators, based on their scores. An effect of memory consolidation was obtained in the hippocampus: Objects that were seen the evening before scanning (remote objects) elicited more activity than objects seen directly before scanning (recent objects). This increase in activity in bilateral hippocampus for remote objects was observed in good navigators only. In addition, a spatial-specific effect of memory consolidation for navigationally relevant objects was observed in the parahippocampal gyrus. Remote decision point objects induced increased activity as compared with recent decision point objects, again in good navigators only. The results provide initial evidence for a connection between memory consolidation and navigational ability that can provide a basis for successful

  9. Classification of error in anatomic pathology: a proposal for an evidence-based standard.

    Foucar, Elliott

    2005-05-01

    Error in anatomic pathology (EAP) is an appropriate problem to consider using the disease model with which all pathologists are familiar. In analogy to medical diseases, diagnostic errors represent a complex constellation of often-baffling deviations from the "normal" condition. Ideally, one would wish to approach such "diseases of diagnosis" with effective treatments or preventative measures, but interventions in the absence of a clear understanding of pathogenesis are often ineffective or even harmful. Medical therapy has its history of "bleeding and purging," and error-prevention has a history of "blaming and shaming." The urge to take action in dealing with either medical illnesses or diagnostic failings is, of course, admirable. However, the principle of primum non nocere should guide one's action in both circumstances. The first step in using the disease model to address EAP is the development of a valid taxonomy to allow for grouping together of abnormalities that have a similar pathogenesis. It is apparent that disease categories such as "tumor" are not valuable until they are further refined by precise and accurate classification. Likewise, "error" is an impossibly broad concept that must be parsed into meaningful subcategories before it can be understood with sufficient clarity to be prevented. One important EAP subtype that has been particularly difficult to understand and classify is knowledge-based interpretative (KBI) error. Not only is the latter sometimes confused with distinctly different error types such as human lapses, but there is danger of mistaking system-wide problems (eg, imprecise or inaccurate diagnostic criteria) for the KBI errors of individual pathologists. This paper presents a theoretically-sound taxonomic system for classification of error that can be used for evidence-based categorization of individual cases. Any taxonomy of error in medicine must distinguish between the various factors that may produce mistakes, and importantly

  10. Anatomical-based partial volume correction for low-dose dedicated cardiac SPECT/CT

    Liu, Hui; Chan, Chung; Grobshtein, Yariv; Ma, Tianyu; Liu, Yaqiang; Wang, Shi; Stacy, Mitchel R.; Sinusas, Albert J.; Liu, Chi

    2015-09-01

    Due to the limited spatial resolution, partial volume effect has been a major degrading factor on quantitative accuracy in emission tomography systems. This study aims to investigate the performance of several anatomical-based partial volume correction (PVC) methods for a dedicated cardiac SPECT/CT system (GE Discovery NM/CT 570c) with focused field-of-view over a clinically relevant range of high and low count levels for two different radiotracer distributions. These PVC methods include perturbation geometry transfer matrix (pGTM), pGTM followed by multi-target correction (MTC), pGTM with known concentration in blood pool, the former followed by MTC and our newly proposed methods, which perform the MTC method iteratively, where the mean values in all regions are estimated and updated by the MTC-corrected images each time in the iterative process. The NCAT phantom was simulated for cardiovascular imaging with 99mTc-tetrofosmin, a myocardial perfusion agent, and 99mTc-red blood cell (RBC), a pure intravascular imaging agent. Images were acquired at six different count levels to investigate the performance of PVC methods in both high and low count levels for low-dose applications. We performed two large animal in vivo cardiac imaging experiments following injection of 99mTc-RBC for evaluation of intramyocardial blood volume (IMBV). The simulation results showed our proposed iterative methods provide superior performance than other existing PVC methods in terms of image quality, quantitative accuracy, and reproducibility (standard deviation), particularly for low-count data. The iterative approaches are robust for both 99mTc-tetrofosmin perfusion imaging and 99mTc-RBC imaging of IMBV and blood pool activity even at low count levels. The animal study results indicated the effectiveness of PVC to correct the overestimation of IMBV due to blood pool contamination. In conclusion, the iterative PVC methods can achieve more accurate quantification, particularly for low

  11. Cleft lip and palate: recommendations for dental anesthetic procedure based on anatomic evidences

    Ivy Kiemle Trindade-Suedam; Bruno Felipe Gaia; Cheong Kuo Cheng; Paulo Alceu Kiemle Trindade; José Carlos da Cunha Bastos; Beatriz Silva Câmara Mattos

    2012-01-01

    Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1) to describe changes in the innervation pattern of anterior teeth and ...

  12. WIKIPEDIA ENTRIES AS A SOURCE OF CAR NAVIGATION LANDMARKS

    N. Binski

    2016-06-01

    Full Text Available Car navigation system devices provide today with an easy and simple solution to the basic concept of reaching a destination. Although these systems usually achieve this goal, they still deliver a limited and poor sequence of instructions that do not consider the human nature of using landmarks during wayfinding. This research paper addresses the concept of enriching navigation route instructions by adding supplementary route information in the form of landmarks. We aim at using a contributed source of landmarks information, which is easy to access, available, show high update rate, and have a large scale of information. For this, Wikipedia was chosen, since it represents the world’s largest free encyclopaedia that includes information about many spatial entities. A survey and classification of available landmarks is implemented, coupled with ranking algorithms based on the entries’ categories and attributes. These are aimed at retrieving the most relevant landmark information required that are valuable for the enrichment of a specific navigation route. The paper will present this methodology, together with examples and results, showing the feasibility of using this concept and its potential of enriching navigation processes.

  13. Wikipedia Entries as a Source of CAR Navigation Landmarks

    Binski, N.; Zhang, L.; Dalyot, S.

    2016-06-01

    Car navigation system devices provide today with an easy and simple solution to the basic concept of reaching a destination. Although these systems usually achieve this goal, they still deliver a limited and poor sequence of instructions that do not consider the human nature of using landmarks during wayfinding. This research paper addresses the concept of enriching navigation route instructions by adding supplementary route information in the form of landmarks. We aim at using a contributed source of landmarks information, which is easy to access, available, show high update rate, and have a large scale of information. For this, Wikipedia was chosen, since it represents the world's largest free encyclopaedia that includes information about many spatial entities. A survey and classification of available landmarks is implemented, coupled with ranking algorithms based on the entries' categories and attributes. These are aimed at retrieving the most relevant landmark information required that are valuable for the enrichment of a specific navigation route. The paper will present this methodology, together with examples and results, showing the feasibility of using this concept and its potential of enriching navigation processes.

  14. Diversity analysis of mangosteen (Garcinia mangostana irradiated by gamma-ray based on morphological and anatomical characteristics

    MUH RAHMAD SUHARTANTO

    2010-01-01

    Full Text Available Widiastuti A, Sobir, Suhartanto MR. 2010. Diversity analysis of mangosteen (Garcinia mangostana L. irradiated by gamma-ray based on morphological and anatomical characteristics. Nusantara Bioscience 2: 23-33. The aim of this research was to increase genetic variability of mangosteen (Garcinia mangostana L. irradiated by gamma rays dosage of 0 Gy, 20 Gy, 25 Gy, 30 Gy,35 Gy and 40 Gy. Plant materials used were seeds collected from Cegal Sub-village, Karacak Village, Leuwiliang Sub-district, Bogor District, West Java. Data was generated from morphological and anatomical characteristics. The result indicated that increasing of gamma ray dosage had inhibited ability of seed to growth, which needed longer time and decreased seed viability. Morphologically, it also decreased plant heigh, stem diameter, leaf seizure, and amount of leaf. Anatomically, stomatal density had positive correlation with plant height by correlation was 90% and 74%. Gamma rays irradiation successfully increase morphological variability until 30%. Seed creavage after irradiation increased variability and survival rate of mangosteen.

  15. Evaluation of contrast reproduction method based on the anatomical guidance of the cerebral images reconstruction in positron emission tomography

    Positron emission tomography is a medical imaging modality providing in-vivo volumetric images of functional processes of the human body, which is used for the diagnosis and the following of neuro degenerative diseases. PET efficiency is however limited by its poor spatial resolution, which generates a decrease of the image local contrast and leads to an under-estimation of small cerebral structures involved in the degenerative mechanism of those diseases. This so-called partial volume effect degradation is usually corrected in a post-reconstruction processing framework through the use of anatomical information, whose spatial resolution allows a better discrimination between functional tissues. However, this kind of method has the major drawback of being very sensitive to the residual mismatches on the anatomical information processing. We developed in this thesis an alternative methodology to compensate for the degradation, by incorporating in the reconstruction process both a model of the system impulse response and an anatomically-based image prior constraint. This methodology was validated by comparison with a post-reconstruction correction strategy, using data from an anthropomorphic phantom acquisition and then we evaluated its robustness to the residual mismatches through a realistic Monte Carlo simulation corresponding to a cerebral exam. The proposed algorithm was finally applied to clinical data reconstruction. (author)

  16. Quality-Aware Estimation of Facial Landmarks in Video Sequences

    Haque, Mohammad Ahsanul; Nasrollahi, Kamal; Moeslund, Thomas B.

    Face alignment in video is a primitive step for facial image analysis. The accuracy of the alignment greatly depends on the quality of the face image in the video frames and low quality faces are proven to cause erroneous alignment. Thus, this paper proposes a system for quality aware face...... alignment by using a Supervised Decent Method (SDM) along with a motion based forward extrapolation method. The proposed system first extracts faces from video frames. Then, it employs a face quality assessment technique to measure the face quality. If the face quality is high, the proposed system uses SDM...... for facial landmark detection. If the face quality is low the proposed system corrects the facial landmarks that are detected by SDM. Depending upon the face velocity in consecutive video frames and face quality measure, two algorithms are proposed for correction of landmarks in low quality faces by...

  17. Model-based dose calculations for COMS eye plaque brachytherapy using an anatomically realistic eye phantom

    Lesperance, Marielle; Inglis-Whalen, M.; Thomson, R. M., E-mail: rthomson@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa K1S 5B6 (Canada)

    2014-02-15

    Purpose : To investigate the effects of the composition and geometry of ocular media and tissues surrounding the eye on dose distributions for COMS eye plaque brachytherapy with{sup 125}I, {sup 103}Pd, or {sup 131}Cs seeds, and to investigate doses to ocular structures. Methods : An anatomically and compositionally realistic voxelized eye model with a medial tumor is developed based on a literature review. Mass energy absorption and attenuation coefficients for ocular media are calculated. Radiation transport and dose deposition are simulated using the EGSnrc Monte Carlo user-code BrachyDose for a fully loaded COMS eye plaque within a water phantom and our full eye model for the three radionuclides. A TG-43 simulation with the same seed configuration in a water phantom neglecting the plaque and interseed effects is also performed. The impact on dose distributions of varying tumor position, as well as tumor and surrounding tissue media is investigated. Each simulation and radionuclide is compared using isodose contours, dose volume histograms for the lens and tumor, maximum, minimum, and average doses to structures of interest, and doses to voxels of interest within the eye. Results : Mass energy absorption and attenuation coefficients of the ocular media differ from those of water by as much as 12% within the 20–30 keV photon energy range. For all radionuclides studied, average doses to the tumor and lens regions in the full eye model differ from those for the plaque in water by 8%–10% and 13%–14%, respectively; the average doses to the tumor and lens regions differ between the full eye model and the TG-43 simulation by 2%–17% and 29%–34%, respectively. Replacing the surrounding tissues in the eye model with water increases the maximum and average doses to the lens by 2% and 3%, respectively. Substituting the tumor medium in the eye model for water, soft tissue, or an alternate melanoma composition affects tumor dose compared to the default eye model

  18. Model-based dose calculations for COMS eye plaque brachytherapy using an anatomically realistic eye phantom

    Purpose : To investigate the effects of the composition and geometry of ocular media and tissues surrounding the eye on dose distributions for COMS eye plaque brachytherapy with125I, 103Pd, or 131Cs seeds, and to investigate doses to ocular structures. Methods : An anatomically and compositionally realistic voxelized eye model with a medial tumor is developed based on a literature review. Mass energy absorption and attenuation coefficients for ocular media are calculated. Radiation transport and dose deposition are simulated using the EGSnrc Monte Carlo user-code BrachyDose for a fully loaded COMS eye plaque within a water phantom and our full eye model for the three radionuclides. A TG-43 simulation with the same seed configuration in a water phantom neglecting the plaque and interseed effects is also performed. The impact on dose distributions of varying tumor position, as well as tumor and surrounding tissue media is investigated. Each simulation and radionuclide is compared using isodose contours, dose volume histograms for the lens and tumor, maximum, minimum, and average doses to structures of interest, and doses to voxels of interest within the eye. Results : Mass energy absorption and attenuation coefficients of the ocular media differ from those of water by as much as 12% within the 20–30 keV photon energy range. For all radionuclides studied, average doses to the tumor and lens regions in the full eye model differ from those for the plaque in water by 8%–10% and 13%–14%, respectively; the average doses to the tumor and lens regions differ between the full eye model and the TG-43 simulation by 2%–17% and 29%–34%, respectively. Replacing the surrounding tissues in the eye model with water increases the maximum and average doses to the lens by 2% and 3%, respectively. Substituting the tumor medium in the eye model for water, soft tissue, or an alternate melanoma composition affects tumor dose compared to the default eye model simulation by up to 16

  19. A New Anatomically Based Nomenclature for the Roots and Root Canals—Part 2: Mandibular Molars

    Denzil Valerian Albuquerque

    2012-01-01

    Full Text Available Several terminologies have been employed in the dental literature to describe the roots and root canal systems of mandibular molars with no consensus being arrived at, thus far. The anatomical relation of roots and their root canals were identified and a naming system was formulated. The proposed nomenclature attempts to make certain essential modifications to the traditional approach to accommodate the naming of various aberrations presented in mandibular molars. A simple, yet extensive nomenclature system has been proposed that appropriately names the internal and external morphology of mandibular molars.

  20. STUDY ON COMPARISON BETWEEN LANDMARK GUIDED (BRINKMAN'S TECHNIQUE ) AND ULTRASOUND GUIDED INTERNAL JUGULAR VEIN CANNULATION

    Vinod; Sashi Walling

    2015-01-01

    Technique of cannulating the central veins , until recently has been based on landmark guided technique . Recently ultrasound machines with high frequency probes are being used to increase success rate and reducing complications. OBJECTIVE: In our study we compare landmark guided technique ( Brinkman's technique ) ( 1 ) with ultrasound guided technique. STUDY DESIGN: outcome was evaluated in terms of 1 ) Number of attempts 2 ) ...

  1. Prognostic classification of Hodgkin disease in pathologic stage III, based on anatomic considerations

    Desser, R.K.; Golomb, H.M.; Ultmann, J.E.; Ferguson, D.J.; Moran, E.M.; Griem, M.L.; Vardiman, J.; Miller, B.; Oetzel, N.; Sweet, D.

    1977-06-01

    Fifty-two patients with pathologic stage III Hodgkin's disease were studied in an effort to determine whether location of involved abdominal nodes influenced survival. Treatment consisted of total nodal radiotherapy with or without subsequent combination chemotherapy. The initial radiation field was the ''extended mantle,'' which included supradiaphragmatic nodes, the splenic hilar area, and paraaortic nodes to the level of L2-L4. Subsequently, lower paraaortic and iliac regions were treated (''lower inverted Y''). Patients with disease limited to the spleen and/or splenic, celiac, or portal nodes (''anatomic substage'' III/sub 1/) had a more favorable 5-yr survival than did patients with involvement of paraaortic, iliac, or mesenteric nodes (''anatomic substage'' III/sub 2/) : 93% versus 57%, respectively (p < 0.05). The addition of combination chemotherapy to total nodal irradiation was associated with improved survival of patients in stage III/sub 2/, but not of those in stage III/sub 1/.

  2. Cleft lip and palate: recommendations for dental anesthetic procedure based on anatomic evidences

    Ivy Kiemle Trindade-Suedam

    2012-02-01

    Full Text Available Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1 to describe changes in the innervation pattern of anterior teeth and soft tissue caused by the presence of a cleft, 2 to describe a local anesthetic procedure in unilateral and bilateral clefts, and 3 to provide recommendations to improve anesthetic procedures in patients with cleft lip and palate. The cases of 2 patients are presented: one with complete unilateral cleft lip and palate, and the other with complete bilateral cleft lip and palate. The patients underwent local anesthesia in the cleft area in order to extract teeth with poor bone support. The modified anesthetic procedure, respecting the altered course of nerves in the cleft maxilla and soft tissue alterations at the cleft site, was accomplished successfully and the tooth extraction was performed with no pain to the patients. General dentists should be aware of the anatomic variations in nerve courses in the cleft area to offer high quality treatment to patients with cleft lip and palate.

  3. Visual landmark-directed scatter-hoarding of Siberian chipmunks Tamias sibiricus.

    Zhang, Dongyuan; Li, Jia; Wang, Zhenyu; Yi, Xianfeng

    2016-05-01

    Spatial memory of cached food items plays an important role in cache recovery by scatter-hoarding animals. However, whether scatter-hoarding animals intentionally select cache sites with respect to visual landmarks in the environment and then rely on them to recover their cached seeds for later use has not been extensively explored. Furthermore, there is a lack of evidence on whether there are sex differences in visual landmark-based food-hoarding behaviors in small rodents even though male and female animals exhibit different spatial abilities. In the present study, we used a scatter-hoarding animal, the Siberian chipmunk, Tamias sibiricus to explore these questions in semi-natural enclosures. Our results showed that T. sibiricus preferred to establish caches in the shallow pits labeled with visual landmarks (branches of Pinus sylvestris, leaves of Athyrium brevifrons and PVC tubes). In addition, visual landmarks of P. sylvestris facilitated cache recovery by T. sibiricus. We also found significant sex differences in visual landmark-based food-hoarding strategies in Siberian chipmunks. Males, rather than females, chipmunks tended to establish their caches with respect to the visual landmarks. Our studies show that T. sibiricus rely on visual landmarks to establish and recover their caches, and that sex differences exist in visual landmark-based food hoarding in Siberian chipmunks. PMID:27160702

  4. Elections and landmark policies in Tanzania and Uganda

    Kjær, Anne Mette; Therkildsen, Ole

    2013-01-01

    political elites to focus on policies they perceive to be able to gain votes. This is based on analyses of six landmark decisions made during the last fifteen years in the social, productive and public finance sectors in Tanzania and Uganda. Such policies share a number of key characteristics: they are...... Tanzania and Uganda....

  5. Fat quantification and analysis of lung transplant patients on unenhanced chest CT images based on standardized anatomic space

    Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.; Wu, Caiyun; Christie, Jason; Lederer, David J.

    2016-03-01

    Chest fat estimation is important for identifying high-risk lung transplant candidates. In this paper, an approach to chest fat quantification based on a recently formulated concept of standardized anatomic space (SAS) is presented. The goal of this paper is to seek answers to the following questions related to chest fat quantification on single slice versus whole volume CT, which have not been addressed in the literature. What level of correlation exists between total chest fat volume and fat areas measured on single abdominal and thigh slices? What is the anatomic location in the chest where maximal correlation of fat area with fat volume can be expected? Do the components of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) have the same area-to-volume correlative behavior or do they differ? The SAS approach includes two steps: calibration followed by transformation which will map the patient slice locations non-linearly to SAS. The optimal slice locations found for SAT and VAT based on SAS are different and at the mid-level of the T8 vertebral body for SAT and mid-level of the T7 vertebral body for VAT. Fat volume and area on optimal slices for SAT and VAT are correlated with Pearson correlation coefficients of 0.97 and 0.86, respectively. The correlation of chest fat volume with abdominal and thigh fat areas is weak to modest.

  6. The Virtual Family-development of surface-based anatomical models of two adults and two children for dosimetric simulations

    The objective of this study was to develop anatomically correct whole body human models of an adult male (34 years old), an adult female (26 years old) and two children (an 11-year-old girl and a six-year-old boy) for the optimized evaluation of electromagnetic exposure. These four models are referred to as the Virtual Family. They are based on high resolution magnetic resonance (MR) images of healthy volunteers. More than 80 different tissue types were distinguished during the segmentation. To improve the accuracy and the effectiveness of the segmentation, a novel semi-automated tool was used to analyze and segment the data. All tissues and organs were reconstructed as three-dimensional (3D) unstructured triangulated surface objects, yielding high precision images of individual features of the body. This greatly enhances the meshing flexibility and the accuracy with respect to thin tissue layers and small organs in comparison with the traditional voxel-based representation of anatomical models. Conformal computational techniques were also applied. The techniques and tools developed in this study can be used to more effectively develop future models and further improve the accuracy of the models for various applications. For research purposes, the four models are provided for free to the scientific community. (note)

  7. Landmark Finding Algorithms for Indoor Autonomous Mobile Robot Localization

    L. Tóth

    2015-12-01

    Full Text Available This contribution is oriented to ways of computer vision algorithms for mobile robot localization in internal and external agricultural environment. The main aim of this work was to design, create, verify and evaluate speed and functionality of computer vision localization algorithm. An input colour camera data and depth data were captured by MS® Kinect sensor that was mounted on 6-wheel-drive mobile robot chassis. The design of the localization algorithm was focused to the most significant blobs and points (landmarks on the colour picture. Actual coordinates of autonomous mobile robot were calculated out from measured distances (depth sensor and calculated angles (RGB camera with respect to landmark points. Time measurement script was used to compare the speed of landmark finding algorithm for localization in case of one and more landmarks on picture. The main source code was written in MS Visual studio C# programming language with Microsoft.Kinect.1.7.dll on Windows based PC. Algorithms described in this article were created for a future development of an autonomous agronomical m obile robot localization and control.

  8. Landmarks selection in street map design

    In Taiwan many electrical maps present their landmarks according to the category of the feature, a designer short of knowledge about mental representation of space, can cause the map to lose its communication effects. To resolve this map design problem, in this research through long-term memory recall, navigation and observation, and short-term memory processing 111 participants were asked to select the proper landmark from study area. The results reveal that in Taiwan convenience stores are the most popular local landmark in rural and urban areas. Their commercial signs have a unique design and bright color. Contrasted to their background, this makes the convenience store a salient feature. This study also developed a rule to assess the priority of the landmarks to design them in different scale maps

  9. Population-based evaluation of a suggested anatomic and clinical classification of congenital heart defects based on the International Paediatric and Congenital Cardiac Code

    Goffinet François

    2011-10-01

    Full Text Available Abstract Background Classification of the overall spectrum of congenital heart defects (CHD has always been challenging, in part because of the diversity of the cardiac phenotypes, but also because of the oft-complex associations. The purpose of our study was to establish a comprehensive and easy-to-use classification of CHD for clinical and epidemiological studies based on the long list of the International Paediatric and Congenital Cardiac Code (IPCCC. Methods We coded each individual malformation using six-digit codes from the long list of IPCCC. We then regrouped all lesions into 10 categories and 23 subcategories according to a multi-dimensional approach encompassing anatomic, diagnostic and therapeutic criteria. This anatomic and clinical classification of congenital heart disease (ACC-CHD was then applied to data acquired from a population-based cohort of patients with CHD in France, made up of 2867 cases (82% live births, 1.8% stillbirths and 16.2% pregnancy terminations. Results The majority of cases (79.5% could be identified with a single IPCCC code. The category "Heterotaxy, including isomerism and mirror-imagery" was the only one that typically required more than one code for identification of cases. The two largest categories were "ventricular septal defects" (52% and "anomalies of the outflow tracts and arterial valves" (20% of cases. Conclusion Our proposed classification is not new, but rather a regrouping of the known spectrum of CHD into a manageable number of categories based on anatomic and clinical criteria. The classification is designed to use the code numbers of the long list of IPCCC but can accommodate ICD-10 codes. Its exhaustiveness, simplicity, and anatomic basis make it useful for clinical and epidemiologic studies, including those aimed at assessment of risk factors and outcomes.

  10. Landmark perception planning for mobile robot localization

    Armingol, José M.; Moreno, Luis; Escalera, Arturo de la; Salichs, Miguel A.

    1998-01-01

    This paper presents a fuzzy perception planner that takes into account the time cost, the suitability of every landmark detection and the different uncertainties the robot encounters along its path for mobile robot localization. The sensor used is a camera with a motorized zoom on a pan & tilt platform and the artificial landmarks are circles detected through normalized grayscale correlation. An Extended Kalman Filter is used to correct the position and orientation of the vehicle. The resulti...

  11. Cortical Terminations of the Inferior Fronto-Occipital and Uncinate Fasciculi: Anatomical Stem-Based Virtual Dissection.

    Hau, Janice; Sarubbo, Silvio; Perchey, Guy; Crivello, Fabrice; Zago, Laure; Mellet, Emmanuel; Jobard, Gaël; Joliot, Marc; Mazoyer, Bernard M; Tzourio-Mazoyer, Nathalie; Petit, Laurent

    2016-01-01

    We combined the neuroanatomists' approach of defining a fascicle as all fibers passing through its compact stem with diffusion-weighted tractography to investigate the cortical terminations of two association tracts, the inferior fronto-occipital fasciculus (IFOF) and the uncinate fasciculus (UF), which have recently been implicated in the ventral language circuitry. The aim was to provide a detailed and quantitative description of their terminations in 60 healthy subjects and to do so to apply an anatomical stem-based virtual dissection, mimicking classical post-mortem dissection, to extract with minimal a priori the IFOF and UF from tractography datasets. In both tracts, we consistently observed more extensive termination territories than their conventional definitions, within the middle and superior frontal, superior parietal and angular gyri for the IFOF and the middle frontal gyrus and superior, middle and inferior temporal gyri beyond the temporal pole for the UF. We revealed new insights regarding the internal organization of these tracts by investigating for the first time the frequency, distribution and hemispheric asymmetry of their terminations. Interestingly, we observed a dissociation between the lateral right-lateralized and medial left-lateralized fronto-occipital branches of the IFOF. In the UF, we observed a rightward lateralization of the orbito-frontal and temporal branches. We revealed a more detailed map of the terminations of these fiber pathways that will enable greater specificity for correlating with diseased populations and other behavioral measures. The limitations of the diffusion tensor model in this study are also discussed. We conclude that anatomical stem-based virtual dissection with diffusion tractography is a fruitful method for studying the structural anatomy of the human white matter pathways. PMID:27252628

  12. Individual 3D region-of-interest atlas of the human brain: knowledge-based class image analysis for extraction of anatomical objects

    Wagenknecht, Gudrun; Kaiser, Hans-Juergen; Sabri, Osama; Buell, Udalrich

    2000-06-01

    After neural network-based classification of tissue types, the second step of atlas extraction is knowledge-based class image analysis to get anatomically meaningful objects. Basic algorithms are region growing, mathematical morphology operations, and template matching. A special algorithm was designed for each object. The class label of each voxel and the knowledge about the relative position of anatomical objects to each other and to the sagittal midplane of the brain can be utilized for object extraction. User interaction is only necessary to define starting, mid- and end planes for most object extractions and to determine the number of iterations for erosion and dilation operations. Extraction can be done for the following anatomical brain regions: cerebrum; cerebral hemispheres; cerebellum; brain stem; white matter (e.g., centrum semiovale); gray matter [cortex, frontal, parietal, occipital, temporal lobes, cingulum, insula, basal ganglia (nuclei caudati, putamen, thalami)]. For atlas- based quantification of functional data, anatomical objects can be convoluted with the point spread function of functional data to take into account the different resolutions of morphological and functional modalities. This method allows individual atlas extraction from MRI image data of a patient without the need of warping individual data to an anatomical or statistical MRI brain atlas.

  13. Encoding and retrieval of landmark-related spatial cues during navigation: an fMRI study.

    Wegman, Joost; Tyborowska, Anna; Janzen, Gabriele

    2014-07-01

    To successfully navigate, humans can use different cues from their surroundings. Learning locations in an environment can be supported by parallel subsystems in the hippocampus and the striatum. We used fMRI to look at differences in the use of object-related spatial cues while 47 participants actively navigated in an open-field virtual environment. In each trial, participants navigated toward a target object. During encoding, three positional cues (columns) with directional cues (shadows) were available. During retrieval, the removed target had to be replaced while either two objects without shadows (objects trial) or one object with a shadow (shadow trial) were available. Participants were informed in blocks about which type of retrieval trial was most likely to occur, thereby modulating expectations of having to rely on a single landmark or on a configuration of landmarks. How the spatial learning systems in the hippocampus and caudate nucleus were involved in these landmark-based encoding and retrieval processes were investigated. Landmark configurations can create a geometry similar to boundaries in an environment. It was found that the hippocampus was involved in encoding when relying on configurations of landmarks, whereas the caudate nucleus was involved in encoding when relying on single landmarks. This might suggest that the observed hippocampal activation for configurations of objects is linked to a spatial representation observed with environmental boundaries. Retrieval based on configurations of landmarks activated regions associated with the spatial updation of object locations for reorientation. When only a single landmark was available during retrieval, regions associated with updating the location of oneself were activated. There was also evidence that good between-participant performance was predicted by right hippocampal activation. This study therefore sheds light on how the brain deals with changing demands on spatial processing related purely

  14. Wavelet-based resolution recovery using an anatomical prior provides quantitative recovery for human population phantom PET [11C]raclopride data

    The objective of this study was to evaluate a resolution recovery (RR) method using a variety of simulated human brain [11C]raclopride positron emission tomography (PET) images. Simulated datasets of 15 numerical human phantoms were processed by a wavelet-based RR method using an anatomical prior. The anatomical prior was in the form of a hybrid segmented atlas, which combined an atlas for anatomical labelling and a PET image for functional labelling of each anatomical structure. We applied RR to both 60 min static and dynamic PET images. Recovery was quantified in 84 regions, comparing the typical ‘true’ value for the simulation, as obtained in normal subjects, simulated and RR PET images. The radioactivity concentration in the white matter, striatum and other cortical regions was successfully recovered for the 60 min static image of all 15 human phantoms; the dependence of the solution on accurate anatomical information was demonstrated by the difficulty of the technique to retrieve the subthalamic nuclei due to mismatch between the two atlases used for data simulation and recovery. Structural and functional synergy for resolution recovery (SFS-RR) improved quantification in the caudate and putamen, the main regions of interest, from −30.1% and −26.2% to −17.6% and −15.1%, respectively, for the 60 min static image and from −51.4% and −38.3% to −27.6% and −20.3% for the binding potential (BPND) image, respectively. The proposed methodology proved effective in the RR of small structures from brain [11C]raclopride PET images. The improvement is consistent across the anatomical variability of a simulated population as long as accurate anatomical segmentations are provided. (paper)

  15. Evaluation of web-based instruction for anatomical interpretation in maxillofacial cone beam computed tomography

    W.T. Al-Rawi; R. Jacobs; B.A. Hassan; G. Sanderink; W.C. Scarfe

    2007-01-01

    Objectives: To evaluate the effectiveness of a web-based instruction in the interpretation of anatomy in images acquired with maxillofacial cone beam CT (CBCT). Methods: An interactive web-based education course for the interpretation of craniofacial CBCT images was recently developed at our institu

  16. Detection of point landmarks in multidimensional tensor data☆

    Ruiz-Alzola, J.; Kikinis, R.; Westin, C.-F.

    2001-01-01

    This paper describes a unified approach to the detection of point landmarks—whose neighborhoods convey discriminant information—including multidimensional scalar, vector, and higher-order tensor data. The method is based on the interpretation of generalized correlation matrices derived from the gradient of tensor functions, a probabilistic interpretation of point landmarks, and the application of tensor algebra. Results on both synthetic and real tensor data are presented.

  17. Associative Basis of Landmark Learning and Integration in Vertebrates

    Leising, Kenneth J.; Blaisdell, Aaron P.

    2009-01-01

    Early work on spatial navigation evaluated what stimuli (kinesthetic or extra-maze) support small-scale navigation and the nature of the underlying learning (place versus response) process. Contemporary research has focused primarily on how cues interact to determine spatial search. This review covers three general findings from research on landmark-based spatial search in vertebrates. First, pigeons and rats encode simple spatial maps in both open-field and touchscreen environments. Second, ...

  18. Online updating of context-aware landmark detectors for prostate localization in daily treatment CT images

    Dai, Xiubin [College of Geographic and Biologic Information, Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu 210015, China and IDEA Lab, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, 130 Mason Farm Road, Chapel Hill, North Carolina 27510 (United States); Gao, Yaozong [IDEA Lab, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, 130 Mason Farm Road, Chapel Hill, North Carolina 27510 (United States); Shen, Dinggang, E-mail: dgshen@med.unc.edu [IDEA Lab, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, 130 Mason Farm Road, Chapel Hill, North Carolina 27510 and Department of Brain and Cognitive Engineering, Korea University, Seoul (Korea, Republic of)

    2015-05-15

    Purpose: In image guided radiation therapy, it is crucial to fast and accurately localize the prostate in the daily treatment images. To this end, the authors propose an online update scheme for landmark-guided prostate segmentation, which can fully exploit valuable patient-specific information contained in the previous treatment images and can achieve improved performance in landmark detection and prostate segmentation. Methods: To localize the prostate in the daily treatment images, the authors first automatically detect six anatomical landmarks on the prostate boundary by adopting a context-aware landmark detection method. Specifically, in this method, a two-layer regression forest is trained as a detector for each target landmark. Once all the newly detected landmarks from new treatment images are reviewed or adjusted (if necessary) by clinicians, they are further included into the training pool as new patient-specific information to update all the two-layer regression forests for the next treatment day. As more and more treatment images of the current patient are acquired, the two-layer regression forests can be continually updated by incorporating the patient-specific information into the training procedure. After all target landmarks are detected, a multiatlas random sample consensus (multiatlas RANSAC) method is used to segment the entire prostate by fusing multiple previously segmented prostates of the current patient after they are aligned to the current treatment image. Subsequently, the segmented prostate of the current treatment image is again reviewed (or even adjusted if needed) by clinicians before including it as a new shape example into the prostate shape dataset for helping localize the entire prostate in the next treatment image. Results: The experimental results on 330 images of 24 patients show the effectiveness of the authors’ proposed online update scheme in improving the accuracies of both landmark detection and prostate segmentation

  19. Support vector machine-based classification of Alzheimer's disease from whole-brain anatomical MRI

    Magnin, Benoit [UMR-S 678, Inserm, Paris (France)]|[UMR-S 610, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France); Mesrob, Lilia [UMR-S 610, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France); Kinkingnehun, Serge [UMR-S 610, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France)]|[BRAIN, Vitry-sur-Seine (France); Pelegrini-Issac, Melanie [UMR-S 678, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France); Colliot, Olivier [IFR 49, Gif-sur-Yvette (France)]|[UPR 640 LENA, CNRS, Paris (France); Sarazin, Marie; Dubois, Bruno [UMR-S 610, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France)]|[Pitie-Salpetriere Hospital, Department of Neurology, Paris (France); Lehericy, Stephane [UMR-S 610, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France)]|[UMPC Univ. Paris 06, Center for NeuroImaging Research-CENIR, Paris (France)]|[Pitie-Salpetriere Hospital, Department of Neuroradiology, Paris (France); Benali, Habib [UMR-S 678, Inserm, Paris (France)]|[UMPC Univ Paris 06, Faculte de Medecine Pitie-Salpetriere, Paris (France)]|[IFR 49, Gif-sur-Yvette (France)]|[UNF/CRIUGM, Universite de Montreal, Montreal, QC (Canada)

    2009-02-15

    We present and evaluate a new automated method based on support vector machine (SVM) classification of whole-brain anatomical magnetic resonance imaging to discriminate between patients with Alzheimer's disease (AD) and elderly control subjects. We studied 16 patients with AD [mean age {+-} standard deviation (SD)=74.1 {+-}5.2 years, mini-mental score examination (MMSE) = 23.1 {+-} 2.9] and 22 elderly controls (72.3{+-}5.0 years, MMSE=28.5{+-} 1.3). Three-dimensional T1-weighted MR images of each subject were automatically parcellated into regions of interest (ROIs). Based upon the characteristics of gray matter extracted from each ROI, we used an SVM algorithm to classify the subjects and statistical procedures based on bootstrap resampling to ensure the robustness of the results. We obtained 94.5% mean correct classification for AD and control subjects (mean specificity, 96.6%; mean sensitivity, 91.5%). Our method has the potential in distinguishing patients with AD from elderly controls and therefore may help in the early diagnosis of AD. (orig.)

  20. Landmark Analysis Of Leaf Shape Using Polygonal Approximation

    Firmansyah, Zakhi; Herdiyeni, Yeni; Paruhum Silalahi, Bib; Douady, Stephane

    2016-01-01

    This research proposes a method to extract landmark of leaf shape using static threshold of polygonal approximation. Leaf shape analysis has played a central role in many problems in vision and perception. Landmark-based shape analysis is the core of geometric morphometric and has been used as a quantitative tool in evolutionary and developmental biology. In this research, the polygonal approximation is used to select the best points that can represent the leaf shape variability. We used a static threshold as the control parameter of fitting a series of line segment over a digital curve of leaf shape. This research focuses on seven leaf shape, i.e., eliptic, obovate, ovate, oblong and special. Experimental results show static polygonal approximation shows can be used to find the important points of leaf shape.

  1. Photocephalometry: errors of projection and landmark location.

    Phillips, C; Greer, J; Vig, P; Matteson, S

    1984-09-01

    A method called photocephalometry was recently described for the possible soft-tissue evaluation of orthognathic surgery patients by the superimposition of coordinated cephalographs and photographs. A grid analysis was performed to determine the accuracy of the superimposition method. In addition, the reliability of landmark identification was analyzed by the method error of Baumrind and Frantz, using three replicates of twelve patients' photographs. Comparison of twenty-one grid intervals showed that the magnification of the photographic image for any given grid plane is not correlated to that of the radiographic image. Accurate comparisons between soft- and hard-tissue anatomy by simply superimposing the images are not feasible because of the difference in the enlargement factors between the photographs and x-ray films. As was noted by Baumrind and Frantz, a wide range exists in the variability of estimating the location of landmarks. Sixty-six percent of the lateral photographic landmarks and 57% of the frontal landmarks had absolute mean errors for all twelve patients that were less than or equal to 2.0 mm. In general, the envelope of error for most landmarks was not circular. Although the photocephalometric apparatus as described by Hohl and colleagues does not yield the desired quantitative correlation between hard and soft tissues, valuable quantitative information on soft tissue can be easily obtained with the standardization and replication possible with the camera setup and enlarged photographs. PMID:6591803

  2. An Efficient Ceiling-view SLAM Using Relational Constraints Between Landmarks

    Hyukdoo Choi; Ryunseok Kim; Euntai Kim

    2014-01-01

    In this paper, we present a new indoor ‘simultaneous localization and mapping’ (SLAM) technique based on an upward-looking ceiling camera. Adapted from our previous work [17], the proposed method employs sparsely-distributed line and point landmarks in an indoor environment to aid with data association and reduce extended Kalman filter computation as compared with earlier techniques. Further, the proposed method exploits geometric relationships between the two types of landmarks to provide ad...

  3. EXPLOITING 3D ULTRASOUND FOR FETAL DIAGNOSTIC PURPOSE THROUGH FACIAL LANDMARKING

    Enrico Vezzetti; Domenico Speranza; Federica Marcolin; Giulia Fracastoro; Giorgia Buscicchio

    2014-01-01

    In the last decade, three-dimensional landmarking has gained attention for different applications, such as face recognition for both identification of suspects and authentication, facial expression recognition, corrective and aesthetic surgery, syndrome study and diagnosis. This work focuses on the last one by proposing a geometrically-based landmark extraction algorithm aimed at diagnosing syndromes on babies before their birth. Pivotal role in this activity is the support provided by physic...

  4. Desert ants learn vibration and magnetic landmarks.

    Cornelia Buehlmann

    Full Text Available The desert ants Cataglyphis navigate not only by path integration but also by using visual and olfactory landmarks to pinpoint the nest entrance. Here we show that Cataglyphis noda can additionally use magnetic and vibrational landmarks as nest-defining cues. The magnetic field may typically provide directional rather than positional information, and vibrational signals so far have been shown to be involved in social behavior. Thus it remains questionable if magnetic and vibration landmarks are usually provided by the ants' habitat as nest-defining cues. However, our results point to the flexibility of the ants' navigational system, which even makes use of cues that are probably most often sensed in a different context.

  5. Surface-Based Analyses of Anatomical Properties of the Visual Cortex in Macular Degeneration.

    Doety Prins

    Full Text Available Macular degeneration (MD can cause a central visual field defect. In a previous study, we found volumetric reductions along the entire visual pathways of MD patients, possibly indicating degeneration of inactive neuronal tissue. This may have important implications. In particular, new therapeutic strategies to restore retinal function rely on intact visual pathways and cortex to reestablish visual function. Here we reanalyze the data of our previous study using surface-based morphometry (SBM rather than voxel-based morphometry (VBM. This can help determine the robustness of the findings and will lead to a better understanding of the nature of neuroanatomical changes associated with MD.The metrics of interest were acquired by performing SBM analysis on T1-weighted MRI data acquired from 113 subjects: patients with juvenile MD (JMD; n = 34, patients with age-related MD (AMD; n = 24 and healthy age-matched controls (HC; n = 55.Relative to age-matched controls, JMD patients showed a thinner cortex, a smaller cortical surface area and a lower grey matter volume in V1 and V2, while AMD patients showed thinning of the cortex in V2. Neither patient group showed a significant difference in mean curvature of the visual cortex.The thinner cortex, smaller surface area and lower grey matter volume in the visual cortex of JMD patients are consistent with our previous results showing a volumetric reduction in their visual cortex. Finding comparable results using two rather different analysis techniques suggests the presence of marked cortical degeneration in the JMD patients. In the AMD patients, we found a thinner cortex in V2 but not in V1. In contrast to our previous VBM analysis, SBM revealed no volumetric reductions of the visual cortex. This suggests that the cortical changes in AMD patients are relatively subtle, as they apparently can be missed by one of the methods.

  6. Electronic and film portal images: a comparison of landmark visibility and review accuracy

    Purpose: To quantitatively compare a scanning liquid ion chamber electronic portal imaging device (SLIC-EPID) and an amorphous silicon flat panel (aSi) EPID with portal film in clinical applications using measures of landmark visibility and treatment review accuracy. Methods and Materials: Six radiation oncologists viewed 39 electronic portal images (EPIs) from the SLIC-EPID, 36 EPIs from the aSi-EPID, and portal films of each of these treatment fields. The physicians rated the clarity of anatomic landmarks in the portal images, and the scores were compared between EPID and film. Nine hundred portal image reviews were performed. EPID and film portal images were acquired with known setup errors in either phantom or cadaver treatments. Physicians identified the errors visually in portal films and with computerized analysis for EPID. Results: There were no statistically significant (p<0.05) differences between film and SLIC-EPID in ratings of landmark clarity. Eleven of 12 landmarks were more visible in aSi-EPID than in film. Translational setup errors were identified with an average accuracy of 2.5 mm in film, compared to 1.5 mm with SLIC-EPID and 1.3 mm with aSi-EPID. Conclusions: Both EPIDs are clinically viable replacements for film, but aSi-EPID represents a significant advancement in image quality over film

  7. TINA manual landmarking tool: software for the precise digitization of 3D landmarks

    Schunke Anja C

    2012-04-01

    Full Text Available Abstract Background Interest in the placing of landmarks and subsequent morphometric analyses of shape for 3D data has increased with the increasing accessibility of computed tomography (CT scanners. However, current computer programs for this task suffer from various practical drawbacks. We present here a free software tool that overcomes many of these problems. Results The TINA Manual Landmarking Tool was developed for the digitization of 3D data sets. It enables the generation of a modifiable 3D volume rendering display plus matching orthogonal 2D cross-sections from DICOM files. The object can be rotated and axes defined and fixed. Predefined lists of landmarks can be loaded and the landmarks identified within any of the representations. Output files are stored in various established formats, depending on the preferred evaluation software. Conclusions The software tool presented here provides several options facilitating the placing of landmarks on 3D objects, including volume rendering from DICOM files, definition and fixation of meaningful axes, easy import, placement, control, and export of landmarks, and handling of large datasets. The TINA Manual Landmark Tool runs under Linux and can be obtained for free from http://www.tina-vision.net/tarballs/.

  8. Locally Linear Diffeomorphic Metric Embedding (LLDME) for surface-based anatomical shape modeling.

    Yang, Xianfeng; Goh, Alvina; Qiu, Anqi

    2011-05-01

    This paper presents the algorithm, Locally Linear Diffeomorphic Metric Embedding (LLDME), for constructing efficient and compact representations of surface-based brain shapes whose variations are characterized using Large Deformation Diffeomorphic Metric Mapping (LDDMM). Our hypothesis is that the shape variations in the infinite-dimensional diffeomorphic metric space can be captured by a low-dimensional space. To do so, traditional Locally Linear Embedding (LLE) that reconstructs a data point from its neighbors in Euclidean space is extended to LLDME that requires interpolating a shape from its neighbors in the infinite-dimensional diffeomorphic metric space. This is made possible through the conservation law of momentum derived from LDDMM. It indicates that initial momentum, a linear transformation of the initial velocity of diffeomorphic flows, at a fixed template shape determines the geodesic connecting the template to a subject's shape in the diffeomorphic metric space and becomes the shape signature of an individual subject. This leads to the compact linear representation of the nonlinear diffeomorphisms in terms of the initial momentum. Since the initial momentum is in a linear space, a shape can be approximated by a linear combination of its neighbors in the diffeomorphic metric space. In addition, we provide efficient computations for the metric distance between two shapes through the first order approximation of the geodesic using the initial momentum as well as for the reconstruction of a shape given its low-dimensional Euclidean coordinates using the geodesic shooting with the initial momentum as the initial condition. Experiments are performed on the hippocampal shapes of 302 normal subjects across the whole life span (18-94years). Compared with Principal Component Analysis and ISOMAP, LLDME provides the most compact and efficient representation of the age-related hippocampal shapes. Even though the hippocampal volumes among young adults are as

  9. Original Rehabilitation Programme after Anatomical ACL Reconstruction Based on MRI Evaluated Graft Remodelling

    Plenzler, Marcin; Straszewski, Dariusz; Ciszkowska-Łysoń, Beata; Śmigielski, Robert; Popieluch, Marcin

    2014-01-01

    Objectives: This study was carried out to design a rehabilitation program allowing for complete functional post-surgical recovery of the limb, that would not affect the remodelling process of the transplanted graft evaluated on MRI imaging. The main reason for changing the rehabilitation protocol was the 14 months of observation of the MRI images (a series of 9 MRIs performed over a two year period) among the patients after ACL reconstruction, in whom the adverse characteristics in remodelling of the graft were observed in line with the implementation of the traditional rehabilitation program. Methods: A 23 years old patient, a professional hi-rank skateboarder, took part in this pilot study. He had a torsion injury of the left knee joint. The main concepts of the rehabilitation program were: functional training in CKC that would involve muscles of the entire kinetic chain of the operated limb; the co-contraction training under the axial load, active extension training, the avoidance of static flexor stretching for at least 24 weeks after the surgery, no passive movements while exercising, the use of posterior translation of the tibia while doing the exercises, and no knee joint extensor strengthening activities in OKC for at least six months after the surgery. In order to evaluate the remodelling of the graft, seven oblique axial MR images (DOA) were taken, on which the graft’s cross-sectional area was measured. The MRI's were performed in the second, sixth, and twelfth week; then in the fourth, sixth, and ninth month, and, finally a year after the surgery. The angle of the graft and PCL was also measured. Additionally, the quality of tendon signal was assessed. For the functional evaluation, isokinetic and isometric tests of the knee extensor and the flexor muscles, along with the tibial rotator functions were performed using Humac Norm device. Postural stability based on COP parameter was established, as well, using the stabilometric platform HUR. For the

  10. Agreement between anatomic and ultrasound measurements of femoral trochlear depth

    Miles, James Edward; Westrup, Ulrik; Eriksen, Thomas

    Assessments of trochlear depth for patients with medial patellar luxation have traditionally been estimated from skyline radiographs or visually during surgery. Ultrasound offers a non-invasive evaluation method which could avoid the need for arthrotomy. We compared anatomic, radiographic and ult...... respective DICOM files which restricts ultrasonographic landmark resolution. Further work on quantifying interobserver variation and repeat measurement variation is required to ensure confidence in this technique....

  11. The accuracy of a designed software for automated localization of craniofacial landmarks on CBCT images

    Two-dimensional projection radiographs have been traditionally considered the modality of choice for cephalometric analysis. To overcome the shortcomings of two-dimensional images, three-dimensional computed tomography (CT) has been used to evaluate craniofacial structures. However, manual landmark detection depends on medical expertise, and the process is time-consuming. The present study was designed to produce software capable of automated localization of craniofacial landmarks on cone beam (CB) CT images based on image registration and to evaluate its accuracy. The software was designed using MATLAB programming language. The technique was a combination of feature-based (principal axes registration) and voxel similarity-based methods for image registration. A total of 8 CBCT images were selected as our reference images for creating a head atlas. Then, 20 CBCT images were randomly selected as the test images for evaluating the method. Three experts twice located 14 landmarks in all 28 CBCT images during two examinations set 6 weeks apart. The differences in the distances of coordinates of each landmark on each image between manual and automated detection methods were calculated and reported as mean errors. The combined intraclass correlation coefficient for intraobserver reliability was 0.89 and for interobserver reliability 0.87 (95% confidence interval, 0.82 to 0.93). The mean errors of all 14 landmarks were <4 mm. Additionally, 63.57% of landmarks had a mean error of <3 mm compared with manual detection (gold standard method). The accuracy of our approach for automated localization of craniofacial landmarks, which was based on combining feature-based and voxel similarity-based methods for image registration, was acceptable. Nevertheless we recommend repetition of this study using other techniques, such as intensity-based methods

  12. 75 FR 69120 - National Natural Landmark Designations

    2010-11-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR... the Interior Dirk Kempthorne designated the following National Natural Landmarks: Big Bone Lick, Boone... administered solely by public agencies; i.e., Federal, State, county or municipal governments. Nearly...

  13. Landmark papers on photorefractive nonlinear optics

    Yeh, Pochi

    1995-01-01

    This book, intended for students, researchers and engineers, is a collection of classic papers on photorefractive nonlinear optics. Included are landmark papers on fundamental photorefractive phenomena, two-wave mixing, four-wave mixing, phase conjugators and resonators, material growth and physics, and applications in image processing, optical storage and optical computing.

  14. The Effect of Electrode Designs Based on the Anatomical Heart Location for the Non-Contact Heart Activity Measurement.

    Gi, Sun Ok; Lee, Young-Jae; Koo, Hye Ran; Lee, Seung Pyo; Lee, Kang-Hwi; Kim, Kyeng-Nam; Kang, Seung-Jin; Lee, Joo Hyeon; Lee, Jeong-Whan

    2015-12-01

    This research is an extension of a previous research [1] on the different effects of sensor location that is relatively suitable for heart rate sensing. This research aimed to elucidate the causes of wide variations in heart rate measurements from the same sensor position among subjects, as observed in previous research [1], and to enhance designs of the inductive textile electrode to overcome these variations. To achieve this, this study comprised two parts: In part 1, X-ray examinations were performed to determine the cause of the wide variations noted in the findings from previous research [1], and we found that at the same sensor position, the heart activity signal differed with slight differences in the positions of the heart of each subject owing to individual differences in the anatomical heart location. In part 2, three types of dual-loop-type textile electrodes were devised to overcome variations in heart location that were confirmed in part 1 of the study. The variations with three types of sensor designs were compared with that with a single-round type of electrode design, by using computer simulation and by performing a t-test on the data obtained from the experiments. We found that the oval-oval shaped, dual-loop-type textile electrode was more suitable than the single round type for determining morphological characteristics as well as for measuring appropriate heart activity signals. Based on these results, the oval-oval, dual-loop-type was a better inductive textile electrode that more effectively overcomes individual differences in heart location during heart activity sensing based on the magnetic-induced conductivity principle. PMID:26490149

  15. Anatomic Total Shoulder System

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: ... you'll be able to watch a live global AP anatomic total shoulder surgery from Methodist Hospital ...

  16. Remembered landmarks enhance the precision of path integration

    Shannon O´Leary

    2005-01-01

    Full Text Available When navigating by path integration, knowledge of one’s position becomes increasingly uncertain as one walks from a known location. This uncertainty decreases if one perceives a known landmark location nearby. We hypothesized that remembering landmarks might serve a similar purpose for path integration as directly perceiving them. If this is true, walking near a remembered landmark location should enhance response consistency in path integration tasks. To test this, we asked participants to view a target and then attempt to walk to it without vision. Some participants saw the target plus a landmark during the preview. Compared with no-landmark trials, response consistency nearly doubled when participants passed near the remembered landmark location. Similar results were obtained when participants could audibly perceive the landmark while walking. A control experiment ruled out perceptual context effects during the preview. We conclude that remembered landmarks can enhance path integration even though they are not directly perceived.

  17. Evaluation of sexual history-based screening of anatomic sites for chlamydia trachomatis and neisseria gonorrhoeae infection in men having sex with men in routine practice

    Jansen Casper L

    2011-07-01

    Full Text Available Abstract Background Sexually transmitted infection (STI screening programmes are implemented in many countries to decrease burden of STI and to improve sexual health. Screening for Chlamydia trachomatis and Neisseria gonorrhoeae has a prominent role in these protocols. Most of the screening programmes concerning men having sex with men (MSM are based on opportunistic urethral testing. In The Netherlands, a history-based approach is used. The aim of this study is to evaluate the protocol of screening anatomic sites for C. trachomatis and N. gonorrhoeae infection based on sexual history in MSM in routine practice in The Netherlands. Methods All MSM visiting the clinic for STI in The Hague are routinely asked about their sexual practice during consulting. As per protocol, tests for urogenital, oropharyngeal and anorectal infection are obtained based on reported site(s of sexual contact. All consultations are entered into a database as part of the national STI monitoring system. Data of an 18 months period were retrieved from this database and analysed. Results A total of 1455 consultations in MSM were registered during the study period. The prevalence of C. trachomatis and N. gonorrhoeae per anatomic site was: urethral infection 4.0% respectively and 2.8%, oropharynx 1.5% and 4.2%, and anorectum 8.2% and 6.0%. The majority of chlamydia cases (72% involved a single anatomic site, which was especially manifest for anorectal infections (79%, while 42% of gonorrhoea cases were single site. Twenty-six percent of MSM with anorectal chlamydia and 17% with anorectal gonorrhoea reported symptoms of proctitis; none of the oropharyngeal infections were symptomatic. Most cases of anorectal infection (83% and oropharyngeal infection (100% would have remained undiagnosed with a symptom-based protocol. Conclusions The current strategy of sexual-history based screening of multiple anatomic sites for chlamydia and gonorrhoea in MSM is a useful and valid guideline

  18. TINA manual landmarking tool: software for the precise digitization of 3D landmarks

    Schunke Anja C; Bromiley Paul A; Tautz Diethard; Thacker Neil A

    2012-01-01

    Abstract Background Interest in the placing of landmarks and subsequent morphometric analyses of shape for 3D data has increased with the increasing accessibility of computed tomography (CT) scanners. However, current computer programs for this task suffer from various practical drawbacks. We present here a free software tool that overcomes many of these problems. Results The TINA Manual Landmarking Tool was developed for the digitization of 3D data sets. It enables the generation of a modifi...

  19. Ultrasound of the elbow: A systematic approach using bony landmarks

    The use of bony landmarks can be helpful in performing an ultrasound study of the elbow. We discuss bony landmarks that can be used for evaluation of the common extensor tendon, ulnar collateral ligament and common flexor tendon, coronoid and olecranon fossa, ulnar nerve, and biceps tendon. We discuss bony landmarks for each of these structures.

  20. Landmarks GIScience for intelligent services

    Richter, Kai-Florian

    2014-01-01

    Summarizes the latest studies on car navigation services, mobile location-based services, museum guides, tourist guides, public transport planners and recent voice interfaces to mobile devices Broadens understanding of spatial applications for smart phones Contains numerous exercises and examples to reinforce concepts

  1. Anatomical imaging for radiotherapy

    Evans, Philip M [Joint Physics Department, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT (United Kingdom)], E-mail: phil.evans@icr.ac.uk

    2008-06-21

    scans is taken on different days. Both allow planning to account for variability intrinsic to the patient. Treatment verification has been carried out using a variety of technologies including: MV portal imaging, kV portal/fluoroscopy, MVCT, conebeam kVCT, ultrasound and optical surface imaging. The various methods have their pros and cons. The four x-ray methods involve an extra radiation dose to normal tissue. The portal methods may not generally be used to visualize soft tissue, consequently they are often used in conjunction with implanted fiducial markers. The two CT-based methods allow measurement of inter-fraction variation only. Ultrasound allows soft-tissue measurement with zero dose but requires skilled interpretation, and there is evidence of systematic differences between ultrasound and other data sources, perhaps due to the effects of the probe pressure. Optical imaging also involves zero dose but requires good correlation between the target and the external measurement and thus is often used in conjunction with an x-ray method. The use of anatomical imaging in radiotherapy allows treatment uncertainties to be determined. These include errors between the mean position at treatment and that at planning (the systematic error) and the day-to-day variation in treatment set-up (the random error). Positional variations may also be categorized in terms of inter- and intra-fraction errors. Various empirical treatment margin formulae and intervention approaches exist to determine the optimum strategies for treatment in the presence of these known errors. Other methods exist to try to minimize error margins drastically including the currently available breath-hold techniques and the tracking methods which are largely in development. This paper will review anatomical imaging techniques in radiotherapy and how they are used to boost the therapeutic benefit of the treatment. (topical review)

  2. Anatomical imaging for radiotherapy

    scans is taken on different days. Both allow planning to account for variability intrinsic to the patient. Treatment verification has been carried out using a variety of technologies including: MV portal imaging, kV portal/fluoroscopy, MVCT, conebeam kVCT, ultrasound and optical surface imaging. The various methods have their pros and cons. The four x-ray methods involve an extra radiation dose to normal tissue. The portal methods may not generally be used to visualize soft tissue, consequently they are often used in conjunction with implanted fiducial markers. The two CT-based methods allow measurement of inter-fraction variation only. Ultrasound allows soft-tissue measurement with zero dose but requires skilled interpretation, and there is evidence of systematic differences between ultrasound and other data sources, perhaps due to the effects of the probe pressure. Optical imaging also involves zero dose but requires good correlation between the target and the external measurement and thus is often used in conjunction with an x-ray method. The use of anatomical imaging in radiotherapy allows treatment uncertainties to be determined. These include errors between the mean position at treatment and that at planning (the systematic error) and the day-to-day variation in treatment set-up (the random error). Positional variations may also be categorized in terms of inter- and intra-fraction errors. Various empirical treatment margin formulae and intervention approaches exist to determine the optimum strategies for treatment in the presence of these known errors. Other methods exist to try to minimize error margins drastically including the currently available breath-hold techniques and the tracking methods which are largely in development. This paper will review anatomical imaging techniques in radiotherapy and how they are used to boost the therapeutic benefit of the treatment. (topical review)

  3. Notes on the Landmark Development of CBR in China

    Dahong Zhuo

    2009-01-01

    Community-based rehabilitation has a history of 22 years in China.In spite of the preliminary achievement and experiences obtained by the pioneering and trial projects,it was not until the beginning of the new century that CBR in China experienced a landmark development.This iS characterized by a number of favorable pohcy by the government for CBR;the mechanism facilitating primary health care with CBR,a new work-force system of CBR reorganized with better motivation and efficiency,99 demonstration projects of CBR bringing about benchmark promotion effect and the active involvement in CBR by social resources agents.

  4. An Image-Based Model of the Whole Human Heart with Detailed Anatomical Structure and Fiber Orientation

    Dongdong Deng; Peifeng Jiao; Xuesong Ye; Ling Xia

    2012-01-01

    Many heart anatomy models have been developed to study the electrophysiological properties of the human heart. However, none of them includes the geometry of the whole human heart. In this study, an anatomically detailed mathematical model of the human heart was firstly reconstructed from the computed tomography images. In the reconstructed model, the atria consisted of atrial muscles, sinoatrial node, crista terminalis, pectinate muscles, Bachmann’s bundle, intercaval bundles, and limbus of ...

  5. Tools for quantitative form description; an evaluation of different software packages for semi-landmark analysis.

    Botton-Divet, Léo; Houssaye, Alexandra; Herrel, Anthony; Fabre, Anne-Claire; Cornette, Raphael

    2015-01-01

    The challenging complexity of biological structures has led to the development of several methods for quantitative analyses of form. Bones are shaped by the interaction of historical (phylogenetic), structural, and functional constrains. Consequently, bone shape has been investigated intensively in an evolutionary context. Geometric morphometric approaches allow the description of the shape of an object in all of its biological complexity. However, when biological objects present only few anatomical landmarks, sliding semi-landmarks may provide good descriptors of shape. The sliding procedure, mandatory for sliding semi-landmarks, requires several steps that may be time-consuming. We here compare the time required by two different software packages ('Edgewarp' and 'Morpho') for the same sliding task, and investigate potential differences in the results and biological interpretation. 'Morpho' is much faster than 'Edgewarp,' notably as a result of the greater computational power of the 'Morpho' software routines and the complexity of the 'Edgewarp' workflow. Morphospaces obtained using both software packages are similar and provide a consistent description of the biological variability. The principal differences between the two software packages are observed in areas characterized by abrupt changes in the bone topography. In summary, both software packages perform equally well in terms of the description of biological structures, yet differ in the simplicity of the workflow and time needed to perform the analyses. PMID:26618086

  6. The behavioural relevance of landmark texture for honeybee homing

    Laura eDittmar

    2011-04-01

    Full Text Available Honeybees visually pinpoint the location of a food source using landmarks. Studies on the role of visual memories have suggested that bees approach the goal by finding a close match between their current view and a memorized view of the goal location. The most relevant landmark features for this matching process seem to be their retinal positions, the size as defined by their edges, and their colour. Recently, we showed that honeybees can use landmarks that are statically camouflaged, suggesting that motion cues are relevant as well. Currently it is unclear how bees weight these different landmark features when accomplishing navigational tasks, and whether this depends on their saliency. Since natural objects are often distinguished by their texture, we investigate the behavioural relevance and the interplay of the spatial configuration and the texture of landmarks. We show that landmark texture is a feature that bees memorise, and being given the opportunity to identify landmarks by their texture improves the bees’ navigational performance. Landmark texture is weighted more strongly than landmark configuration when it provides the bees with positional information and when the texture is salient. In the vicinity of the landmark honeybees changed their flight behaviour according to its texture.

  7. Three-dimensional in vivo imaging of the murine liver: a micro-computed tomography-based anatomical study.

    Teresa Fiebig

    Full Text Available Various murine models are currently used to study acute and chronic pathological processes of the liver, and the efficacy of novel therapeutic regimens. The increasing availability of high-resolution small animal imaging modalities presents researchers with the opportunity to precisely identify and describe pathological processes of the liver. To meet the demands, the objective of this study was to provide a three-dimensional illustration of the macroscopic anatomical location of the murine liver lobes and hepatic vessels using small animal imaging modalities. We analysed micro-CT images of the murine liver by integrating additional information from the published literature to develop comprehensive illustrations of the macroscopic anatomical features of the murine liver and hepatic vasculature. As a result, we provide updated three-dimensional illustrations of the macroscopic anatomy of the murine liver and hepatic vessels using micro-CT. The information presented here provides researchers working in the field of experimental liver disease with a comprehensive, easily accessable overview of the macroscopic anatomy of the murine liver.

  8. Basic Restriction and Reference Level in Anatomically-based Japanese Models for Low-Frequency Electric and Magnetic Field Exposures

    Takano, Yukinori; Hirata, Akimasa; Fujiwara, Osamu

    Human exposed to electric and/or magnetic fields at low frequencies may cause direct effect such as nerve stimulation and excitation. Therefore, basic restriction is regulated in terms of induced current density in the ICNIRP guidelines and in-situ electric field in the IEEE standard. External electric or magnetic field which does not produce induced quantities exceeding the basic restriction is used as a reference level. The relationship between the basic restriction and reference level for low-frequency electric and magnetic fields has been investigated using European anatomic models, while limited for Japanese model, especially for electric field exposures. In addition, that relationship has not well been discussed. In the present study, we calculated the induced quantities in anatomic Japanese male and female models exposed to electric and magnetic fields at reference level. A quasi static finite-difference time-domain (FDTD) method was applied to analyze this problem. As a result, spatially averaged induced current density was found to be more sensitive to averaging algorithms than that of in-situ electric field. For electric and magnetic field exposure at the ICNIRP reference level, the maximum values of the induced current density for different averaging algorithm were smaller than the basic restriction for most cases. For exposures at the reference level in the IEEE standard, the maximum electric fields in the brain were larger than the basic restriction in the brain while smaller for the spinal cord and heart.

  9. The use of radial symmetry to localize retinal landmarks.

    Giachetti, A; Ballerini, L; Trucco, E; Wilson, P J

    2013-01-01

    Locating the optic disc center and the fovea in digital fundus images is surprisingly difficult due to the variation range in color and contrast and the possible presence of pathologies creating bright spots or changing the appearance of retinal landmarks. These reasons make it difficult to find good templates of optic disc and fovea shape and color for pattern matching. In this paper we propose radial symmetry as the principal cue to locate both optic disc and macula centers. Centers of bright and dark circularly symmetrical regions with arbitrary radii, can be found robustly against changes in brightness and contrast by using the Fast Radial Symmetry transform. Detectors based on this transform coupled with a weak hypothesis on vessel density (optic disc intersects large vessels while the fovea lies in an avascular region), can provide a fast location of both OD and macula with accuracy similar or better than state-of-the-art methods. The approach has been chosen as the default technique for fast localization of the two landmarks in the VAMPIRE software suite. PMID:23886574

  10. An Efficient Ceiling-view SLAM Using Relational Constraints Between Landmarks

    Hyukdoo Choi

    2014-01-01

    Full Text Available In this paper, we present a new indoor ‘simultaneous localization and mapping’ (SLAM technique based on an upward-looking ceiling camera. Adapted from our previous work [17], the proposed method employs sparsely-distributed line and point landmarks in an indoor environment to aid with data association and reduce extended Kalman filter computation as compared with earlier techniques. Further, the proposed method exploits geometric relationships between the two types of landmarks to provide added information about the environment. This geometric information is measured with an upward-looking ceiling camera and is used as a constraint in Kalman filtering. The performance of the proposed ceiling-view (CV SLAM is demonstrated through simulations and experiments. The proposed method performs localization and mapping more accurately than those methods that use the two types of landmarks without taking into account their relative geometries.

  11. Geodesic distances to landmarks for dense correspondence on ensembles of complex shapes.

    Datar, Manasi; Lyu, Ilwoo; Kim, SunHyung; Cates, Joshua; Styner, Martin A; Whitaker, Ross

    2013-01-01

    Establishing correspondence points across a set of biomedical shapes is an important technology for a variety of applications that rely on statistical analysis of individual subjects and populations. The inherent complexity (e.g. cortical surface shapes) and variability (e.g. cardiac chambers) evident in many biomedical shapes introduce significant challenges in finding a useful set of dense correspondences. Application specific strategies, such as registration of simplified (e.g. inflated or smoothed) surfaces or relying on manually placed landmarks, provide some improvement but suffer from limitations including increased computational complexity and ambiguity in landmark placement. This paper proposes a method for dense point correspondence on shape ensembles using geodesic distances to a priori landmarks as features. A novel set of numerical techniques for fast computation of geodesic distances to point sets is used to extract these features. The proposed method minimizes the ensemble entropy based on these features, resulting in isometry invariant correspondences in a very general, flexible framework. PMID:24579119

  12. Navigating virtual mazes : The benefits of audiovisual landmarks

    Werkhoven, P.; Erp, J.B.F. van; Philippi, T.G.

    2014-01-01

    It has been shown that multisensory presentation can improve perception, attention, and object memory compared with unisensory presentation. Consequently, we expect that multisensory presentation of landmarks can improve spatial memory and navigation. In this study we tested the effect of visual, auditory and combined landmark presentations in virtual mazes on spatial memory and spatial navigation. Nineteen participants explored four different virtual mazes consisting of nodes with landmarks ...

  13. The Behavioral Relevance of Landmark Texture for Honeybee Homing

    Laura eDittmar; Martin eEgelhaaf; Wolfgang eStürzl; Norbert eBoeddeker

    2011-01-01

    Honeybees visually pinpoint the location of a food source using landmarks. Studies on the role of visual memories have suggested that bees approach the goal by finding a close match between their current view and a memorized view of the goal location. The most relevant landmark features for this matching process seem to be their retinal positions, the size as defined by their edges, and their colour. Recently, we showed that honeybees can use landmarks that are statically camouflaged, suggest...

  14. Using landmarks to support older people in navigation

    Goodman, J.; Gray, P.D.G.; Khammampad, K.; Brewster, S.

    2004-01-01

    Although landmarks are an integral aspect of navigation, they have rarely been used within electronic navigation aids. This paper describes the design of a pedestrian navigation aid for a handheld computer, which guides the user along a route using photographs of landmarks, together with audio and text instructions that reference these landmarks. This aid was designed with older users in mind who often find their mobility hampered by declines in sensory, cognitive and motor abilities. It was ...

  15. Optimization of abdominal fat quantification on CT imaging through use of standardized anatomic space: A novel approach

    Purpose: The quantification of body fat plays an important role in the study of numerous diseases. It is common current practice to use the fat area at a single abdominal computed tomography (CT) slice as a marker of the body fat content in studying various disease processes. This paper sets out to answer three questions related to this issue which have not been addressed in the literature. At what single anatomic slice location do the areas of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) estimated from the slice correlate maximally with the corresponding fat volume measures? How does one ensure that the slices used for correlation calculation from different subjects are at the same anatomic location? Are there combinations of multiple slices (not necessarily contiguous) whose area sum correlates better with volume than does single slice area with volume? Methods: The authors propose a novel strategy for mapping slice locations to a standardized anatomic space so that same anatomic slice locations are identified in different subjects. The authors then study the volume-to-area correlations and determine where they become maximal. To address the third issue, the authors carry out similar correlation studies by utilizing two and three slices for calculating area sum. Results: Based on 50 abdominal CT data sets, the proposed mapping achieves significantly improved consistency of anatomic localization compared to current practice. Maximum correlations are achieved at different anatomic locations for SAT and VAT which are both different from the L4-L5 junction commonly utilized currently for single slice area estimation as a marker. Conclusions: The maximum area-to-volume correlation achieved is quite high, suggesting that it may be reasonable to estimate body fat by measuring the area of fat from a single anatomic slice at the site of maximum correlation and use this as a marker. The site of maximum correlation is not at L4-L5 as commonly assumed

  16. UAV Control on the Basis of 3D Landmark Bearing-Only Observations.

    Karpenko, Simon; Konovalenko, Ivan; Miller, Alexander; Miller, Boris; Nikolaev, Dmitry

    2015-01-01

    The article presents an approach to the control of a UAV on the basis of 3D landmark observations. The novelty of the work is the usage of the 3D RANSAC algorithm developed on the basis of the landmarks' position prediction with the aid of a modified Kalman-type filter. Modification of the filter based on the pseudo-measurements approach permits obtaining unbiased UAV position estimation with quadratic error characteristics. Modeling of UAV flight on the basis of the suggested algorithm shows good performance, even under significant external perturbations. PMID:26633394

  17. 36 CFR 62.7 - Natural landmark modifications.

    2010-07-01

    ... nationally significant features, professional error in the original designation, or additional landowners... landmark: Loss of integrity of the natural features or professional error in the original designation....

  18. Morphological measurements of anatomic landmarks in pulp chambers of human anterior teeth.

    Lee, Myong M; Rasimick, Brian J; Turner, Aura M; Shah, Rinal P; Musikant, Barry Lee; Deutsch, Allan S

    2007-02-01

    This in vitro study measured key morphological features of pulp chambers in anterior teeth and tested the hypothesis that the distance from the lingual surface (midpoint from the cusp tip to the lingual CEJ) to the pulp chamber (the midpoint from the buccal to the lingual CEJ) was similar for different tooth types. Extracted human teeth were sorted and 100 samples of each of the following tooth types were chosen: maxillary central incisor (UCI), lateral incisor (ULI), and canine (UC), as well as mandibular central incisor (LCI), lateral incisor (LLI), and canine (LC). All teeth were digitally radiographed on a 1-mm X-ray grid. The mean values of measurement C, the distance from the lingual surface to the pulp chamber, varied significantly between tooth types (pUC (5.5+/-0.5)=UCI (5.4+/-0.4)>ULI (5.0+/-0.4)>LLI (4.8+/-0.5)>LCI (4.4+/-0.4). PMID:17258629

  19. Cochlear implant electrode insertion: Jacobson’s nerve, a useful anatomical landmark

    Goravalingappa, Ravi

    2002-01-01

    The classical technique in approaching the scala tympani through the round window niche by way of facial recess has not always been successful. There have been recent reports on false insertion of the electrode array into the hypotympanic cells tracts or infralabrynithine cells tracts. In these cases the round window niche are situated posterior, or obliterated due to bony growth, or sclerosed at the basal turn of the cochlea. Therefore, successful intubation of the scala tympani much depends...

  20. Algorithms to automatically quantify the geometric similarity of anatomical surfaces

    Boyer, D; Clair, E St; Puente, J; Funkhouser, T; Patel, B; Jernvall, J; Daubechies, I

    2011-01-01

    We describe new approaches for distances between pairs of 2-dimensional surfaces (embedded in 3-dimensional space) that use local structures and global information contained in inter-structure geometric relationships. We present algorithms to automatically determine these distances as well as geometric correspondences. This is motivated by the aspiration of students of natural science to understand the continuity of form that unites the diversity of life. At present, scientists using physical traits to study evolutionary relationships among living and extinct animals analyze data extracted from carefully defined anatomical correspondence points (landmarks). Identifying and recording these landmarks is time consuming and can be done accurately only by trained morphologists. This renders these studies inaccessible to non-morphologists, and causes phenomics to lag behind genomics in elucidating evolutionary patterns. Unlike other algorithms presented for morphological correspondences our approach does not requir...

  1. Tridimensional Regression for Comparing and Mapping 3D Anatomical Structures

    Kendra K. Schmid

    2012-01-01

    Full Text Available Shape analysis is useful for a wide variety of disciplines and has many applications. There are many approaches to shape analysis, one of which focuses on the analysis of shapes that are represented by the coordinates of predefined landmarks on the object. This paper discusses Tridimensional Regression, a technique that can be used for mapping images and shapes that are represented by sets of three-dimensional landmark coordinates, for comparing and mapping 3D anatomical structures. The degree of similarity between shapes can be quantified using the tridimensional coefficient of determination (2. An experiment was conducted to evaluate the effectiveness of this technique to correctly match the image of a face with another image of the same face. These results were compared to the 2 values obtained when only two dimensions are used and show that using three dimensions increases the ability to correctly match and discriminate between faces.

  2. Post-trial anatomical frame alignment procedure for comparison of 3D joint angle measurement from magnetic/inertial measurement units and camera-based systems

    Magnetic and inertial measurement units (MIMUs) have been widely used as an alternative to traditional camera-based motion capture systems for 3D joint kinematics measurement. Since these sensors do not directly measure position, a pre-trial anatomical calibration, either with the assistance of a special protocol/apparatus or with another motion capture system is required to establish the transformation matrices between the local sensor frame and the anatomical frame (AF) of each body segment on which the sensors are attached. Because the axes of AFs are often used as the rotational axes in the joint angle calculation, any difference in the AF determination will cause discrepancies in the calculated joint angles. Therefore, a direct comparison of joint angles between MIMU systems and camera-based systems is less meaningful because the calculated joint angles contain a systemic error due to the differences in the AF determination. To solve this problem a new post-trial AF alignment procedure is proposed. By correcting the AF misalignments, the joint angle differences caused by the difference in AF determination are eliminated and the remaining discrepancies are mainly from the measurement accuracy of the systems themselves. Lower limb joint angles from 30 walking trials were used to validate the effectiveness of the proposed AF alignment procedure. This technique could serve as a new means for calibrating magnetic/inertial sensor-based motion capture systems and correcting for AF misalignment in scenarios where joint angles are compared directly. (paper)

  3. EXPLOITING 3D ULTRASOUND FOR FETAL DIAGNOSTIC PURPOSE THROUGH FACIAL LANDMARKING

    Enrico Vezzetti

    2014-06-01

    Full Text Available In the last decade, three-dimensional landmarking has gained attention for different applications, such as face recognition for both identification of suspects and authentication, facial expression recognition, corrective and aesthetic surgery, syndrome study and diagnosis. This work focuses on the last one by proposing a geometrically-based landmark extraction algorithm aimed at diagnosing syndromes on babies before their birth. Pivotal role in this activity is the support provided by physicians and 3D ultrasound tools for working on real faces. In particular, the landmarking algorithm here proposed only relies on descriptors coming from Differential Geometry (Gaussian, mean, and principal curvatures, derivatives, coefficients of first and second fundamental forms, Shape and Curvedness indexes and is tested on nine facial point clouds referred to nine babies taken by a three-dimensional ultrasound tool at different weeks' gestation. The results obtained, validated with the support of four practitioners, show that the localization is quite accurate. All errors lie in the range between 0 and 3.5 mm and the mean distance for each shell is in the range between 0.6 and 1.6 mm. The landmarks showing the highest errors are the ones belonging to the mouth region. Instead, the most precise landmark is the pronasal, on the nose tip, with a mean distance of 0.55 mm. Relying on current literature, this study is something missing in the state-of-the-art of the field, as present facial studies on 3D ultrasound do not work on automatic landmarking yet.

  4. Precision landmark location for machine vision and photogrammetry finding and achieving the maximum possible accuracy

    Gutierrez, José A

    2007-01-01

    Shows the reader how to derive theoretical limits to the precision of landmark identification in electronic imagesMATLAB® package assists the reader with applying theoretical results in real engineering systemsSteps outside the usual earth-sciences and civil-engineering base of photogrammetry to improve animation, medical imaging and robotic vision applications

  5. Anatomic Total Shoulder System

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: DePuy Orthopedics is continually advancing the standard of orthopedic patient care. In a few ...

  6. Anatomic Total Shoulder System

    Full Text Available ... Orthopedics is continually advancing the standard of orthopedic patient care. In a few moments, you'll be ... and version variability which allows adaptability to a patient's unique anatomical makeup. Dr. Gerald R. Williams, Jr., ...

  7. Anatomic Total Shoulder System

    Full Text Available ... to a patient's unique anatomical makeup. Dr. Gerald R. Williams, Jr., a shoulder specialist from the Rothman ... That might help. Could you raise the O.R. table, please? 00:28:35 WOMAN: Can you ...

  8. Anatomic Total Shoulder System

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: DePuy Orthopedics is continually advancing the standard of orthopedic patient ...

  9. 基于CPR和CLM的多视角人脸特征点定位方法%A Multi-view Facial Landmark Localization Method Based on CPR and CLM

    石正权; 赵启军; 陈虎

    2015-01-01

    准确定位人脸特征点在人脸识别、三维人脸模型重建等领域都有重要作用.目前,针对正面人脸的特征点定位已经相当成熟;但是,当姿态偏转角较大时,准确定位人脸特征点依然是一个有待解决的难题.文中针对姿态偏转比较大的特征点定位,提出了一种多视角人脸特征点定位方法.在训练阶段,针对不同姿态角度,分别定义其特征点模板,并通过训练得到用于特征点搜索的CPR(级联姿态回归)模型和用于特征点模板选择的CLM (约束局部模型)模型.在测试阶段,利用每个模型分别对测试样本进行特征点搜索,然后,利用CLM模型计算各特征点模板的拟合度,选择拟合度最高的模型作为最终结果.在FERET公开库上,与当前比较先进的算法进行的对比实验表明,文中方法有效提高了较大偏转姿态下人脸特征点定位的准确性.%Facial landmark localization plays an important role in many face-related applications such as face recognition and 3D face re-construction. Although existing methods already achieve promising results on frontal and near-frontal face images,their performance on face images with large pose angles is still far from being satisfactory. A multi-view facial landmark localization method is proposed in this paper. It divides head pose angles into a number of non-overlapping ranges. During training,for each range of head pose angles,a facial landmark template is constructed by using the CPR (Cascaded Pose Regression) method,and a corresponding texture model is established by using the CLM (Constrained Local Model) method. During testing,given a new face image,all the templates are applied to it,each resulting in a set of facial landmarks. The associated texture models are then used to compute the fitness values of them,from which the one with the maximum fitness is chosen as the final result. Experiments on the FERET database with comparison to a state-of-the-art method

  10. Quantitation of maxillary remodeling. 2. Masking of remodeling effects when an "anatomical" method of superimposition is used in the absence of metallic implants.

    Baumrind, S; Korn, E L; Ben-Bassat, Y; West, E E

    1987-06-01

    We report the results of a study aimed at quantifying the differences in the perceived pattern of maxillary remodeling that are observed when different methods are used to superimpose maxillary images in roentgenographic cephalometrics. In a previous article, we reported cumulative changes in the positions of anterior nasal spine (ANS), posterior nasal spine (PNS), and Point A for a sample of 31 subjects with maxillary metallic implants. Measurements had been made on lateral cephalograms taken at annual intervals relative to superimposition on the implants. In the present article, we quantify the differences in the perceived displacement of the same landmarks in the same sample when a standard "anatomical best bit" rule was used in lieu of superimposition on the implants. The anatomical best fit superimposition as herein defined was found in this sample to lose important information on the downward remodeling of the superior surface of the maxilla that had been detected when the implant superimposition was used. In fact, we observed a small artifactual upward displacement of the ANS-PNS line. In the anteroposterior direction, the tendency toward backward displacement of skeletal landmarks through time that had been detected with the implant superimposition was replaced by a small forward displacement of ANS and Point A together with reduced backward displacement of PNS. To the extent that the implant superimposition is to be considered the true and correct one, the anatomical best fit superimposition appears to understate the true downward remodeling of the palate by an average of about 0.3 and 0.4 mm per year, although this value differs at different ages and timepoints. The anatomical best fit superimposition also misses entirely the small mean tendency toward backward remodeling that was observed when the implant superimposition was used. In situations in which there are no implants, clinicians and research workers must necessarily continue to use anatomically

  11. Chronic Pancreatitis: Landmark Papers, Management Decisions, and Future.

    DiMagno, Eugene P; DiMagno, Matthew J

    2016-01-01

    On May 16, 2015 at the invitation of the American Gastroenterological Association Institute Council E.P.D. presented a state-of-the-art lecture at Digestive Disease Week 2015. The aims were to discuss a selection of landmark papers in chronic pancreatitis (CP) that influence modern management and to conclude by suggesting some future directions. This is based on that presentation. We will specifically review the following: duct anatomy and pancreas divisum, description of chronic relapsing pancreatitis and its differentiation from recurrent acute pancreatitis and established CP (ECP), natural histories and gene discoveries of alcoholic, idiopathic and hereditary pancreatitis, development of pancreatic cancer in CP, exocrine pancreatic insufficiency and calculation of dose and delivery of enzymes, endoscopic ultrasonography, and autoimmune pancreatitis. With some exceptions, we exclude basic science and surgery. PMID:27077713

  12. Computer-aided diagnostic scheme for the detection of lung nodules on chest radiographs: Localized search method based on anatomical classification

    We developed an advanced computer-aided diagnostic (CAD) scheme for the detection of various types of lung nodules on chest radiographs intended for implementation in clinical situations. We used 924 digitized chest images (992 noncalcified nodules) which had a 500x500 matrix size with a 1024 gray scale. The images were divided randomly into two sets which were used for training and testing of the computerized scheme. In this scheme, the lung field was first segmented by use of a ribcage detection technique, and then a large search area (448x448 matrix size) within the chest image was automatically determined by taking into account the locations of a midline and a top edge of the segmented ribcage. In order to detect lung nodule candidates based on a localized search method, we divided the entire search area into 7x7 regions of interest (ROIs: 64x64 matrix size). In the next step, each ROI was classified anatomically into apical, peripheral, hilar, and diaphragm/heart regions by use of its image features. Identification of lung nodule candidates and extraction of image features were applied for each localized region (128x128 matrix size), each having its central part (64x64 matrix size) located at a position corresponding to a ROI that was classified anatomically in the previous step. Initial candidates were identified by use of the nodule-enhanced image obtained with the average radial-gradient filtering technique, in which the filter size was varied adaptively depending on the location and the anatomical classification of the ROI. We extracted 57 image features from the original and nodule-enhanced images based on geometric, gray-level, background structure, and edge-gradient features. In addition, 14 image features were obtained from the corresponding locations in the contralateral subtraction image. A total of 71 image features were employed for three sequential artificial neural networks (ANNs) in order to reduce the number of false-positive candidates. All

  13. Tracking in anatomic pathology.

    Pantanowitz, Liron; Mackinnon, Alexander C; Sinard, John H

    2013-12-01

    Bar code-based tracking solutions, long present in clinical pathology laboratories, have recently made an appearance in anatomic pathology (AP) laboratories. Tracking of AP "assets" (specimens, blocks, slides) can enhance laboratory efficiency, promote patient safety, and improve patient care. Routing of excess clinical material into research laboratories and biorepositories are other avenues that can benefit from tracking of AP assets. Implementing tracking is not as simple as installing software and turning it on. Not all tracking solutions are alike. Careful analysis of laboratory workflow is needed before implementing tracking to assure that this solution will meet the needs of the laboratory. Such analysis will likely uncover practices that may need to be modified before a tracking system can be deployed. Costs that go beyond simply that of purchasing software will be incurred and need to be considered in the budgeting process. Finally, people, not technology, are the key to assuring quality. Tracking will require significant changes in workflow and an overall change in the culture of the laboratory. Preparation, training, buy-in, and accountability of the people involved are crucial to the success of this process. This article reviews the benefits, available technology, underlying principles, and implementation of tracking solutions for the AP and research laboratory. PMID:23634908

  14. Visual motion-sensitive neurons in the bumblebee brain convey information about landmarks during a navigational task

    Marcel eMertes

    2014-09-01

    Full Text Available Bees use visual memories to find the spatial location of previously learnt food sites. Characteristic learning flights help acquiring these memories at newly discovered foraging locations where landmarks - salient objects in the vicinity of the goal location - can play an important role in guiding the animal’s homing behavior. Although behavioral experiments have shown that bees can use a variety of visual cues to distinguish objects as landmarks, the question of how landmark features are encoded by the visual system is still open. Recently, it could be shown that motion cues are sufficient to allow bees localizing their goal using landmarks that can hardly be discriminated from the background texture. Here, we tested the hypothesis that motion sensitive neurons in the bee’s visual pathway provide information about such landmarks during a learning flight and might, thus, play a role for goal localization. We tracked learning flights of free-flying bumblebees (Bombus terrestris in an arena with distinct visual landmarks, reconstructed the visual input during these flights, and replayed ego-perspective movies to tethered bumblebees while recording the activity of direction-selective wide-field neurons in their optic lobe. By comparing neuronal responses during a typical learning flight and targeted modifications of landmark properties in this movie we demonstrate that these objects are indeed represented in the bee’s visual motion pathway. We find that object-induced responses vary little with object texture, which is in agreement with behavioral evidence. These neurons thus convey information about landmark properties that are useful for view-based homing.

  15. A multi-atlas based method for automated anatomical rat brain MRI segmentation and extraction of PET activity.

    Sophie Lancelot

    Full Text Available INTRODUCTION: Preclinical in vivo imaging requires precise and reproducible delineation of brain structures. Manual segmentation is time consuming and operator dependent. Automated segmentation as usually performed via single atlas registration fails to account for anatomo-physiological variability. We present, evaluate, and make available a multi-atlas approach for automatically segmenting rat brain MRI and extracting PET activies. METHODS: High-resolution 7T 2DT2 MR images of 12 Sprague-Dawley rat brains were manually segmented into 27-VOI label volumes using detailed protocols. Automated methods were developed with 7/12 atlas datasets, i.e. the MRIs and their associated label volumes. MRIs were registered to a common space, where an MRI template and a maximum probability atlas were created. Three automated methods were tested: 1/registering individual MRIs to the template, and using a single atlas (SA, 2/using the maximum probability atlas (MP, and 3/registering the MRIs from the multi-atlas dataset to an individual MRI, propagating the label volumes and fusing them in individual MRI space (propagation & fusion, PF. Evaluation was performed on the five remaining rats which additionally underwent [18F]FDG PET. Automated and manual segmentations were compared for morphometric performance (assessed by comparing volume bias and Dice overlap index and functional performance (evaluated by comparing extracted PET measures. RESULTS: Only the SA method showed volume bias. Dice indices were significantly different between methods (PF>MP>SA. PET regional measures were more accurate with multi-atlas methods than with SA method. CONCLUSIONS: Multi-atlas methods outperform SA for automated anatomical brain segmentation and PET measure's extraction. They perform comparably to manual segmentation for FDG-PET quantification. Multi-atlas methods are suitable for rapid reproducible VOI analyses.

  16. The accuracy of the central landmark used for central venous catheterization of the internal jugular vein.

    Bailey, Peter L; Whitaker, Emmett E; Palmer, Linda S; Glance, Laurent G

    2006-05-01

    We simulated needle paths based on the central landmark used for central venous catheterization of the internal jugular vein. We obtained ultrasound images to quantify the landmark's accuracy (precision and bias) in 107 subjects placed in Trendelenburg position with their heads turned 30-35 degrees. We also determined the frequency of simulated carotid artery puncture. The simulated needle path missed the middle 80% of the lumen of the internal jugular vein in 34% of subjects (95% confidence interval [CI], 25% to 44%) and traversed the carotid artery in 26% of subjects (95% CI, 18% to 35%). Both events occurred in 20% of subjects (95% CI, 13%-29%). The landmark had a medial bias of 3.7 mm (95% CI, 2.7 to 4.8); it was more often (77 of 104 subjects) medial to the center of the right internal jugular vein (P yield frequent success on first needle pass without risk of carotid puncture because of its imprecision and bias. The measured bias should be considered when the central landmark is used for central venous catheterization. PMID:16632804

  17. White matter abnormalities in young males with antisocial personality disorder Evidence from voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis

    Daxing Wu; Ying Zhao; Jian Liao; Huifang Yin; Wei Wang

    2011-01-01

    Voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis was used to investigate the structural characteristics of white matter in young males with antisocial personality disorder (APD) and healthy controls without APD. The results revealed that APD subjects, relative to healthy subjects, exhibited increased white matter volume in the bilateral prefrontal lobe, right insula, precentral gyrus, bilateral superior temporal gyrus, right postcentral gyrus, right inferior parietal lobule, right precuneus, right middle occipital lobe, right parahippocampal gyrus and bilateral cingulate, and decreased volume in the middle temporal cortex and right cerebellum. The white matter volume in the medial frontal gyrus was significantly correlated with antisocial type scores on the Personality Diagnostic Questionnaire in APD subjects. These experimental findings indicate that white matter abnormalities in several brain areas may contribute to antisocial behaviors in APD subjects.

  18. The location of midfacial landmarks according to the method of establishing the midsagittal reference plane in three-dimensional computed tomography analysis of facial asymmetry

    Kim, Min Sun; Lee, Eun Joo; Lee, Jae Seo; Kang, Byung Cheock; Yoon, Suk Ja [Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of); Song, In Ja [Dept. of Nursing, Kwangju Women' s University, Gwangju (Korea, Republic of)

    2015-12-15

    The purpose of this study was to evaluate the influence of methods of establishing the midsagittal reference plane (MRP) on the locations of midfacial landmarks in the three-dimensional computed tomography (CT) analysis of facial asymmetry. A total of 24 patients (12 male and 12 female; mean age, 22.5 years; age range, 18.2-29.7 years) with facial asymmetry were included in this study. The MRP was established using two different methods on each patient's CT image. The x-coordinates of four midfacial landmarks (the menton, nasion, upper incisor, and lower incisor) were obtained by measuring the distance and direction of the landmarks from the MRP, and the two methods were compared statistically. The direction of deviation and the severity of asymmetry found using each method were also compared. The x-coordinates of the four anatomic landmarks all showed a statistically significant difference between the two methods of establishing the MRP. For the nasion and lower incisor, six patients (25.0%) showed a change in the direction of deviation. The severity of asymmetry also changed in 16 patients (66.7%). The results of this study suggest that the locations of midfacial landmarks change significantly according to the method used to establish the MRP.

  19. An anatomically oriented breast model for MRI

    Kutra, Dominik; Bergtholdt, Martin; Sabczynski, Jörg; Dössel, Olaf; Buelow, Thomas

    2015-03-01

    Breast cancer is the most common cancer in women in the western world. In the breast cancer care-cycle, MRIis e.g. employed in lesion characterization and therapy assessment. Reading of a single three dimensional image or comparing a multitude of such images in a time series is a time consuming task. Radiological reporting is done manually by translating the spatial position of a finding in an image to a generic representation in the form of a breast diagram, outlining quadrants or clock positions. Currently, registration algorithms are employed to aid with the reading and interpretation of longitudinal studies by providing positional correspondence. To aid with the reporting of findings, knowledge about the breast anatomy has to be introduced to translate from patient specific positions to a generic representation. In our approach we fit a geometric primitive, the semi-super-ellipsoid to patient data. Anatomical knowledge is incorporated by fixing the tip of the super-ellipsoid to the mammilla position and constraining its center-point to a reference plane defined by landmarks on the sternum. A coordinate system is then constructed by linearly scaling the fitted super-ellipsoid, defining a unique set of parameters to each point in the image volume. By fitting such a coordinate system to a different image of the same patient, positional correspondence can be generated. We have validated our method on eight pairs of baseline and follow-up scans (16 breasts) that were acquired for the assessment of neo-adjuvant chemotherapy. On average, the location predicted and the actual location of manually set landmarks are within a distance of 5.6 mm. Our proposed method allows for automatic reporting simply by uniformly dividing the super-ellipsoid around its main axis.

  20. Anatomic Total Shoulder System

    Full Text Available ... AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: DePuy ... you don't make a bunch of small passes at the lesser tuberosity and make it a ...

  1. Anatomic Total Shoulder System

    Full Text Available ... Anatomic Total Shoulder surgery, which featured the latest innovation in shoulder surgery from DePuy Orthopedics. OR-Live makes it easy for you to learn more. Just click on the "Request Information" button on your webcast screen and open the door to informed medical care. 01:21: ...

  2. Anatomic Total Shoulder System

    Full Text Available ... advancing the standard of orthopedic patient care. In a few moments, you'll be able to watch a live global AP anatomic total shoulder surgery from Methodist Hospital in Philadelphia. A revolution in shoulder orthopedics, the Global AP gives ...

  3. Anatomic Total Shoulder System

    Full Text Available ... by almost ten years, is shoulders. So by definition, the average shoulder-replacement patient is almost ten ... Anatomic Total Shoulder surgery, which featured the latest innovation in shoulder surgery from DePuy Orthopedics. OR-Live ...

  4. US of the Peripheral Nerves of the Upper Extremity: A Landmark Approach.

    Brown, Jordan M; Yablon, Corrie M; Morag, Yoav; Brandon, Catherine J; Jacobson, Jon A

    2016-01-01

    Ultrasonography (US) has become a first-line modality for the evaluation of the peripheral nerves of the upper extremity. The benefits of US over magnetic resonance (MR) imaging include higher soft-tissue resolution, cost effectiveness, portability, real-time and dynamic imaging, and the ability to scan an entire extremity quickly and efficiently. US can be performed on patients who are not eligible for MR imaging. Metallic implant artifacts are usually not problematic. US has been shown to have equal specificity and greater sensitivity than MR imaging in the evaluation of peripheral nerves. Any abnormal findings can be easily compared with the contralateral side. The published literature has shown that US has demonstrated clinical utility in patients with suspected peripheral nerve disease by guiding diagnostic and therapeutic decisions as well as by confirming electrodiagnostic findings. Common indications for upper extremity peripheral nerve US are the evaluation for injury due to penetrating trauma, entrapment by scar tissue, and tumor. US of the upper extremity is most commonly performed to evaluate carpal and cubital tunnel syndrome. It is important for the radiologist or sonographer to have a detailed knowledge of anatomy and specific anatomic landmarks for each nerve to efficiently and accurately perform an examination. The goal of this article is to introduce readers to the basics of US of the peripheral nerves of the upper extremity with a focus on the median, ulnar, and radial nerves. Common sites of disease and the location of important anatomic landmarks will be reviewed. (©)RSNA, 2016. PMID:26963456

  5. Single Robot Localisation Approach for Indoor Robotic Systems through Integration of Odometry and Artificial Landmarks

    Ņikitenko, A; Liekna, A; Ekmanis, M.; Kuļikovskis, G; Andersone, I

    2013-01-01

    we present an integrated approach for robot localization that allows to integrate for the artificial landmark localization data with odometric sensors and signal transfer function data to provide means for different practical application scenarios. The sensor data fusion deals with asynchronous sensor data using inverse Laplace transform. We demonstrate a simulation software system that ensures smooth integration of the odometry-based and signal transfer – based localization into one approach.

  6. Pigeons combine compass and landmark guidance in familiar route navigation

    Biro, Dora; Freeman, Robin; Meade, Jessica; Roberts, Stephen; Guilford, Tim

    2007-01-01

    How do birds orient over familiar terrain? In the best studied avian species, the homing pigeon (Columba livia), two apparently independent primary mechanisms are currently debated: either memorized visual landmarks provide homeward guidance directly, or birds rely on a compass to home from familiar locations. Using miniature Global Positioning System tracking technology and clock-shift procedures, we set sun-compass and landmark information in conflict, showing that experienced birds can acc...

  7. Landmarks of History of Soil Science in Sri Lanka

    Mapa, R.

    2012-04-01

    Sri Lanka is a tropical Island in the Southern tip of Indian subcontinent positioned at 50 55' to 90 50' N latitude and 790 42' to 810 53' E longitude surrounded by the Indian Ocean. It is an island 435 km in length and 224 km width consisting of a land are of 6.56 million ha with a population of 20 million. In area wise it is ranked as 118th in the world, where at present ranked as 47 in population wise and ranked 19th in population density. The country was under colonial rule under Portuguese, Dutch and British from 1505 to 1948. The majority of the people in the past and present earn their living from activities based on land, which indicates the important of the soil resource. The objective of this paper is to describe the landmarks of the history of Soil Science to highlight the achievements and failures, which is useful to enrich our present understanding of Sri Lankan soils. The landmarks of the history of Soil Science in Sri Lanka can be divided to three phases namely, the early period (prior to 1956), the middle period (1956 to 1972) and the present period (from 1972 onwards). During the early period, detailed analytical studies of coffee and tea soils were compiled, and these gave mainly information on up-country soils which led to fertilizer recommendations based on field trials. In addition, rice and forest soils were also studied in less detail. The first classification of Sri Lankan soils and a provisional soil map based on parent material was published by Joachim in 1945 which is a major landmark of history of Soil Science in Sri Lanka. In 1959 Ponnamperuma proposed a soil classification system for wetland rice soils. From 1963 to 1968 valuable information on the land resource was collected and documented by aerial resource surveys funded by Canada-Ceylon Colombo plan aid project. This covered 18 major river basins and about 1/4th of Sri Lanka, which resulted in producing excellent soil maps and information of the areas called the Kelani Aruvi Ara

  8. Three-dimensional study of pelvic asymmetry on anatomical specimens and its clinical perspectives

    Boulay, C.; Tardieu, C; Benaim, C.; Hecquet, J.; MARTY C.; Prat-Pradal, D.; Legaye, Jean; Duval-Beaupère, Ginette; Pelissier, J.

    2006-01-01

    The aim of this study was to assess pelvic asymmetry (i.e. to determine whether the right iliac bone and the right part of the sacrum are mirror images of the left), both quantitatively and qualitatively, using three-dimensional measurements. Pelvic symmetry was described osteologically using a common reference coordinate system for a large sample of pelvises. Landmarks were established on 12 anatomical specimens with an electromagnetic Fastrak system. Seventy-one paired variables were tested...

  9. Anatomical demonstration of the Internal Thoracic Artery and its implication in the Myocardial Revascularization Surgery

    Fernández Aramburu, Julián; Villegas, Lucas; Mas, Antonela; Froján, Diego; Gaillard, Juan Manuel; Loccisano, Matías

    2012-01-01

    The internal thoracic artery (ITA), also known as internal mammary artery (IMA) is often used in coronary artery bypass graft. The knowledge of its morphology, thus its major side branches, is essential to the cardiovascular surgeon. The aim of this work is to provide a description of the collateral branches of the ITA, providing anatomical landmarks for its identification (in our case the transversus thoracis muscle) and quantification as a basis for myocardial revascularization surgery usin...

  10. Anatomical mapping of the nasal muscles and application to cosmetic surgery.

    Konschake, Marko; Fritsch, Helga

    2014-11-01

    We present an anatomical mapping of the most important muscles influencing the nose, incorporating constant anatomical structures, and their spatial correlations. At our disposal were the midfaces of 18 bodies of both sexes, obtained by informed consent from body donors aged between 60 and 80 years. Macroscopically, we dissected the nasal regions of eight corpses, six midfaces were prepared according to plastination histology, four by creating plastinated slices. On their way from their periosteal origin to the edge of the skin, the muscles of the nose cross the subcutaneous adipose tissue, dividing it into superficial and deep layers. The individual muscle fibers insert into the skin directly at the reticular corium. Sometimes, they reach the border of the epidermis which represents a special arrangement of corial muscle attachments. The course of the anatomical fibers of individual nasal muscles presented macroscopically and microscopically in this study offers surgeons a detailed overview of the anatomically important muscular landmarks of the midface. PMID:24863980

  11. Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra provides reduced effect of scanner for cortex volumetry with atlas-based method in healthy subjects

    Goto, Masami; Ino, Kenji; Yano, Keiichi [University of Tokyo Hospital, Department of Radiological Technology, Bunkyo-ku, Tokyo (Japan); Abe, Osamu [Nihon University School of Medicine, Department of Radiology, Itabashi-ku, Tokyo (Japan); Aoki, Shigeki [Juntendo University, Department of Radiology, Bunkyo-ku, Tokyo (Japan); Hayashi, Naoto [University of Tokyo Hospital, Department of Computational Diagnostic Radiology and Preventive Medicine, Bunkyo-ku, Tokyo (Japan); Miyati, Tosiaki [Kanazawa University, Graduate School of Medical Science, Kanazawa (Japan); Takao, Hidemasa; Mori, Harushi; Kunimatsu, Akira; Ohtomo, Kuni [University of Tokyo Hospital, Department of Radiology and Department of Computational Diagnostic Radiology and Preventive Medicine, Bunkyo-ku, Tokyo (Japan); Iwatsubo, Takeshi [University of Tokyo, Department of Neuropathology, Bunkyo-ku, Tokyo (Japan); Yamashita, Fumio [Iwate Medical University, Department of Radiology, Yahaba, Iwate (Japan); Matsuda, Hiroshi [Integrative Brain Imaging Center National Center of Neurology and Psychiatry, Department of Nuclear Medicine, Kodaira, Tokyo (Japan); Collaboration: Japanese Alzheimer' s Disease Neuroimaging Initiative

    2013-07-15

    This study aimed to investigate whether the effect of scanner for cortex volumetry with atlas-based method is reduced using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) normalization compared with standard normalization. Three-dimensional T1-weighted magnetic resonance images (3D-T1WIs) of 21 healthy subjects were obtained and evaluated for effect of scanner in cortex volumetry. 3D-T1WIs of the 21 subjects were obtained with five MRI systems. Imaging of each subject was performed on each of five different MRI scanners. We used the Voxel-Based Morphometry 8 tool implemented in Statistical Parametric Mapping 8 and WFU PickAtlas software (Talairach brain atlas theory). The following software default settings were used as bilateral region-of-interest labels: ''Frontal Lobe,'' ''Hippocampus,'' ''Occipital Lobe,'' ''Orbital Gyrus,'' ''Parietal Lobe,'' ''Putamen,'' and ''Temporal Lobe.'' Effect of scanner for cortex volumetry using the atlas-based method was reduced with DARTEL normalization compared with standard normalization in Frontal Lobe, Occipital Lobe, Orbital Gyrus, Putamen, and Temporal Lobe; was the same in Hippocampus and Parietal Lobe; and showed no increase with DARTEL normalization for any region of interest (ROI). DARTEL normalization reduces the effect of scanner, which is a major problem in multicenter studies. (orig.)

  12. [Establishment of anatomical terminology in Japan].

    Shimada, Kazuyuki

    2008-12-01

    The history of anatomical terminology in Japan began with the publication of Waran Naikei Ihan-teimŏ in 1805 and Chŏtei Kaitai Shinsho in 1826. Although the establishment of Japanese anatomical terminology became necessary during the Meiji era when many western anatomy books imported into Janan were translated, such terminology was not unified during this period and varied among translators. In 1871, Tsukumo Ono's Kaibŏgaku Gosen was published by the Ministry of Education. Although this book is considered to be the first anatomical glossary terms in Japan, its contents were incomplete. Overseas, the German Anatomical Society established a unified anatomical terminology in 1895 called the Basle Nomina Anatomica (B.N.A.). Based on this development, Kaibŏgaku Meishŭ which follows the BNA, by Buntarŏ Suzuki was published in 1905. With the subsequent establishment in 1935 of Jena Nomina Anatomica (J.N.A.), the unification of anatomical terminology was also accelerated in Japan, leading to the further development of terminology. PMID:19108488

  13. Reference Man anatomical model

    Cristy, M.

    1994-10-01

    The 70-kg Standard Man or Reference Man has been used in physiological models since at least the 1920s to represent adult males. It came into use in radiation protection in the late 1940s and was developed extensively during the 1950s and used by the International Commission on Radiological Protection (ICRP) in its Publication 2 in 1959. The current Reference Man for Purposes of Radiation Protection is a monumental book published in 1975 by the ICRP as ICRP Publication 23. It has a wealth of information useful for radiation dosimetry, including anatomical and physiological data, gross and elemental composition of the body and organs and tissues of the body. The anatomical data includes specified reference values for an adult male and an adult female. Other reference values are primarily for the adult male. The anatomical data include much data on fetuses and children, although reference values are not established. There is an ICRP task group currently working on revising selected parts of the Reference Man document.

  14. Genomic differentiation of Neanderthals and anatomically modern man allows a fossil-DNA-based classification of morphologically indistinguishable hominid bones.

    Scholz, M.; Bachmann, L; Nicholson, G J; Bachmann, J.; Giddings, I; Rüschoff-Thale, B; Czarnetzki, A; Pusch, C. M.

    2000-01-01

    Southern blot hybridizations of genomic DNA were introduced as a relatively simple fossil-DNA-based approach to classify remains of Neanderthals. When hybridized with genomic DNA of either human or Neanderthal origin, DNA extracted from two Neanderthal finds-the Os parietale, from Warendorf-Neuwarendorf, Germany, and a clavicula, from Krapina, Croatia-was shown to yield hybridization signals that differ by at least a factor of two compared to the signals obtained with the use of fossil DNA of...

  15. Pilot study: Computer-based virtual anatomical interactivity for rehabilitation of individuals with chronic acquired brain injury

    C. Douglas Simmons, PhD, OTR/L, FAOTA; Sajay Arthanat, PhD, OTR/L, ATP; Vincent J. Macri, BA, MA

    2014-01-01

    Deficiencies in upper-limb motor function and executive functioning can compromise an affected individual’s ability to complete everyday activities. Impaired motor and executive functioning therefore pose a risk to increasing numbers of veterans who have been diagnosed with acquired brain injury. This article reports on changes in upper-limb motor function and executive functioning of 12 adult participants with chronic acquired brain injury using a novel, computer-based, motor and cognitive r...

  16. Design, construction and mechanical testing of digital 3D anatomical data-based PCL-HA bone tissue engineering scaffold.

    Yao, Qingqiang; Wei, Bo; Guo, Yang; Jin, Chengzhe; Du, Xiaotao; Yan, Chao; Yan, Junwei; Hu, Wenhao; Xu, Yan; Zhou, Zhi; Wang, Yijin; Wang, Liming

    2015-01-01

    The study aims to investigate the techniques of design and construction of CT 3D reconstructional data-based polycaprolactone (PCL)-hydroxyapatite (HA) scaffold. Femoral and lumbar spinal specimens of eight male New Zealand white rabbits were performed CT and laser scanning data-based 3D printing scaffold processing using PCL-HA powder. Each group was performed eight scaffolds. The CAD-based 3D printed porous cylindrical stents were 16 piece × 3 groups, including the orthogonal scaffold, the Pozi-hole scaffold and the triangular hole scaffold. The gross forms, fiber scaffold diameters and porosities of the scaffolds were measured, and the mechanical testing was performed towards eight pieces of the three kinds of cylindrical scaffolds, respectively. The loading force, deformation, maximum-affordable pressure and deformation value were recorded. The pore-connection rate of each scaffold was 100 % within each group, there was no significant difference in the gross parameters and micro-structural parameters of each scaffold when compared with the design values (P > 0.05). There was no significant difference in the loading force, deformation and deformation value under the maximum-affordable pressure of the three different cylinder scaffolds when the load was above 320 N. The combination of CT and CAD reverse technology could accomplish the design and manufacturing of complex bone tissue engineering scaffolds, with no significant difference in the impacts of the microstructures towards the physical properties of different porous scaffolds under large load. PMID:25596860

  17. Modeling and matching of landmarks for automation of Mars Rover localization

    Wang, Jue

    The Mars Exploration Rover (MER) mission, begun in January 2004, has been extremely successful. However, decision-making for many operation tasks of the current MER mission and the 1997 Mars Pathfinder mission is performed on Earth through a predominantly manual, time-consuming process. Unmanned planetary rover navigation is ideally expected to reduce rover idle time, diminish the need for entering safe-mode, and dynamically handle opportunistic science events without required communication to Earth. Successful automation of rover navigation and localization during the extraterrestrial exploration requires that accurate position and attitude information can be received by a rover and that the rover has the support of simultaneous localization and mapping. An integrated approach with Bundle Adjustment (BA) and Visual Odometry (VO) can efficiently refine the rover position. However, during the MER mission, BA is done manually because of the difficulty in the automation of the cross-sitetie points selection. This dissertation proposes an automatic approach to select cross-site tie points from multiple rover sites based on the methods of landmark extraction, landmark modeling, and landmark matching. The first step in this approach is that important landmarks such as craters and rocks are defined. Methods of automatic feature extraction and landmark modeling are then introduced. Complex models with orientation angles and simple models without those angles are compared. The results have shown that simple models can provide reasonably good results. Next, the sensitivity of different modeling parameters is analyzed. Based on this analysis, cross-site rocks are matched through two complementary stages: rock distribution pattern matching and rock model matching. In addition, a preliminary experiment on orbital and ground landmark matching is also briefly introduced. Finally, the reliability of the cross-site tie points selection is validated by fault detection, which

  18. Delivering high-resolution landmarks using inkjet micropatterning for spatial monitoring of leaf expansion

    Cronk Quentin CB; Beyer Simon T; Wang Lisheng; Walus Konrad

    2011-01-01

    Abstract Background Inkjet micropatterning is a versatile deposition technique with broad applications in numerous fields. However, its application in plant science is largely unexplored. Leaf expansion is one of the most important parameters in the field of plant science and many methods have been developed to examine differential expansion rates of different parts of the leaf lamina. Among them, methods based on the tracking of natural landmarks through digital imaging require a complicated...

  19. Variants of the supplying vessels of the vascularized iliac bone graft and their relationship to important surgical landmarks.

    Ghassemi, Alireza; Furkert, Robert; Prescher, Andreas; Riediger, Dieter; Knobe, Matthias; O'dey, Dan; Gerressen, Marcus

    2013-05-01

    The iliac bone crest is one of the most valuable regions for harvesting bone grafts, both vascularized and nonvascularized. Since the first commendable description of this region as a possible source for vascularized bone flaps by Taylor, little relevant information concerning the variations of the deep circumflex iliac vessels and their relationship to the neighboring structures has been published. The purpose of the current study was to examine this region clinically and anatomically, taking into consideration the former description by Taylor. We gathered all our findings on 216 iliac regions and proposed a new classification. In addition we measured the relationships between the deep circumflex iliac artery and important surgical landmarks. A comparison of our finding with other studies showed similarities and differences but was far more complete. Generally (92%) the deep circumflex iliac artery (DCIA) originated from external iliac artery (EIA) behind the inguinal ligament (IL) and passed cranio-laterally toward the anterior superior iliac spine, where it divided into two important branches. Four variations were observed of the DCIA. The deep circumflex iliac vein (DCIV) ran over (82.5%) or under (17.5%) the EIA. The superficial circumflex iliac vein (SCIV) was observed draining into the DCIV in some dissections. Three different variations of the superficial circumflex iliac artery (SCIA) were observed. The anatomical knowledge of these variations and their correlation to important surgical landmarks can help in harvesting the DCIA flap more safely and thus increasing the success rate while reducing donor site morbidity. PMID:23355300

  20. Assessment of organ doses from exposure to neutrons using the Monte Carlo technique and an image-based anatomical model

    Bozkurt, Ahmet

    The distribution of absorbed doses in the body can be computationally determined using mathematical or tomographic representations of human anatomy. A whole- body model was developed from the color images of the National Library of Medicine's Visible Human Project® for simulating the transport of radiation in the human body. The model, called Visible Photographic Man (VIP-Man), has sixty-one organs and tissues represented in the Monte Carlo code MCNPX at 4-mm voxel resolution. Organ dose calculations from external neutron sources were carried out using VIP-man and MCNPX to determine a new set of dose conversion coefficients to be used in radiation protection. Monoenergetic neutron beams between 10-9 MeV and 10 GeV were studied under six different irradiation geometries: anterior-posterior, posterior-anterior, right lateral, left lateral, rotational and isotropic. The results for absorbed doses in twenty-four organs and the effective doses based on twelve critical organs are presented in tabular form. A comprehensive comparison of the results with those from the mathematical models show discrepancies that can be attributed to the variations in body modeling (size, location and shape of the individual organs) and the use of different nuclear datasets or models to derive the reaction cross sections, as well as the use of different transport packages for simulation radiation effects. The organ dose results based on the realistic VIP-Man body model allow the existing radiation protection dosimetry on neutrons to be re-evaluated and improved.

  1. Pilot study: Computer-based virtual anatomical interactivity for rehabilitation of individuals with chronic acquired brain injury

    C. Douglas Simmons, PhD, OTR/L, FAOTA

    2014-06-01

    Full Text Available Deficiencies in upper-limb motor function and executive functioning can compromise an affected individual’s ability to complete everyday activities. Impaired motor and executive functioning therefore pose a risk to increasing numbers of veterans who have been diagnosed with acquired brain injury. This article reports on changes in upper-limb motor function and executive functioning of 12 adult participants with chronic acquired brain injury using a novel, computer-based, motor and cognitive rehabilitation program called PreMotor Exercise Games (PEGs. Manual muscle, goniometric range of motion, and dynamometer assessments were used to determine motor functioning while the Executive Function Performance Test measured cognitive functioning. A three-level repeated measures design was conducted to determine changes pre- and postintervention. Participants demonstrated significant improvement in shoulder (p = 0.01 and wrist (p = 0.01 range of motion and clinically relevant improvement for elbow range of motion. Participants demonstrated clinically relevant improvement in shoulder, elbow, and wrist strength. Finally, participants demonstrated significant improvement in executive functioning (p < 0.05. Using PEGs as a modality for both motor and cognitive intervention is a potentially beneficial adjunct to rehabilitation and warrants further study.

  2. Lateral femoral cutaneous neuralgia: an anatomical insight.

    Dias Filho, L C; Valença, M M; Guimarães Filho, F A V; Medeiros, R C; Silva, R A M; Morais, M G V; Valente, F P; França, S M L

    2003-07-01

    A detailed anatomic study was carried out on the lateral femoral cutaneous nerve to better understand the etiology and treatment of lateral femoral cutaneous neuralgia. As it passed from the pelvis into the thigh, the lateral femoral cutaneous nerve ran through an "aponeuroticofascial tunnel," beginning at the iliopubic tract and ending at the inguinal ligament; as it passed through the tunnel, an enlargement in its side-to-side diameter was observed, suggesting that the fascial structures proximal to the inguinal ligament may be implicated in the genesis of lateral femoral cutaneous neuralgia. The finding of pseudoneuromas at this location, distant from the inguinal ligament, supports this hypothesis. The anterior superior iliac spine is located approximately 0.7 cm from the lateral femoral cutaneous nerve and serves as the bony landmark for nerve localization. Within the first 3 cm of leaving the pelvis, the lateral femoral cutaneous nerve was observed deep to the fascia lata; therefore, surgical dissection within the subcutaneous fascia may be conducted with relative impunity near the anterior superior iliac spine just inferior to the inguinal ligament. In 36% of cases there was no posterior branch of the nerve, which is correlated to lateral femoral cutaneous neuralgia symptoms often being limited to the anterior branch region. An accessory nerve was found in 30% of cases. PMID:12794914

  3. Development and application of stent-based image guided navigation system for oral and maxillofacial surgery

    The purpose of this study was to develop a stent-based image guided surgery system and to apply it to oral and maxillofacial surgeries for anatomically complex sites. We devised a patient-specific stent for patient-to-image registration and navigation. Three dimensional positions of the reference probe and the tool probe were tracked by an optical camera system and the relative position of the handpiece drill tip to the reference probe was monitored continuously on the monitor of a PC. Using 8 landmarks for measuring accuracy, the spatial discrepancy between CT image coordinate and physical coordinate was calculated for testing the normality. The accuracy over 8 anatomical landmarks showed an overall mean of 0.56 ± 0.16 mm. The developed system was applied to a surgery for a vertical alveolar bone augmentation in right mandibular posterior area and possible interior alveolar nerve injury case of an impacted third molar. The developed system provided continuous monitoring of invisible anatomical structures during operation and 3D information for operation sites. The clinical challenge showed sufficient accuracy and availability of anatomically complex operation sites. The developed system showed sufficient accuracy and availability in oral and maxillofacial surgeries for anatomically complex sites.

  4. Digital imaging in anatomic pathology.

    O'Brien, M J; Sotnikov, A V

    1996-10-01

    Advances in computer technology continue to bring new innovations to departments of anatomic pathology. This article briefly reviews the present status of digital optical imaging, and explores the directions that this technology may lead over the next several years. Technical requirements for digital microscopic and gross imaging, and the available options for image archival and retrieval are summarized. The advantages of digital images over conventional photography in the conference room, and the usefulness of digital imaging in the frozen section suite and gross room, as an adjunct to surgical signout and as a resource for training and education, are discussed. An approach to the future construction of digital histologic sections and the computer as microscope is described. The digital technologic applications that are now available as components of the surgical pathologist's workstation are enumerated. These include laboratory information systems, computerized voice recognition, and on-line or CD-based literature searching, texts and atlases and, in some departments, on-line image databases. The authors suggest that, in addition to these resources that are already available, tomorrow's surgical pathology workstation will include network-linked digital histologic databases, on-line software for image analysis and 3-D image enhancement, expert systems, and ultimately, advanced pattern recognition capabilities. In conclusion, the authors submit that digital optical imaging is likely to have a significant and positive impact on the future development of anatomic pathology. PMID:8853053

  5. Spatial Language and Children’s Spatial Landmark Use

    Amber A. Ankowski

    2012-01-01

    Full Text Available We examined how spatial language affected search behavior in a landmark spatial search task. In Experiment 1, two- to six-year-old children were trained to find a toy in the center of a square array of four identical landmarks. Children heard one of three spatial language cues once during the initial training trial (“here,” “in the middle,” “next to this one”. After search performance reached criterion, children received a probe test trial in which the landmark array was expanded. In Experiment 2, two- to four-year-old children participated in the search task and also completed a language comprehension task. Results revealed that children’s spatial language comprehension scores and spatial language cues heard during training trials were related to children’s performance in the search task.

  6. PC Assisted Anatomical Measurements in 3D Using CT Data

    Hvidtfeldt, Mogens; Pedersen, Steen

    1999-01-01

    To assess facilities and applications of a programme for a PC based CT measurements in 3D of anatomical angelse in the skeleton.......To assess facilities and applications of a programme for a PC based CT measurements in 3D of anatomical angelse in the skeleton....

  7. Effects of cephalometric landmark validity on incisor angulation.

    Chan, C K; Tng, T H; Hägg, U; Cooke, M S

    1994-11-01

    An experimental cephalometric study on the accuracy of independently locating eight landmarks and the subsequent effects on the maxillary (ILs/NL) and mandibular (ILi/ML) incisor angulation was carried out on 30 dry skulls. The true location of each landmark was marked with a steel ball glued onto the skulls. Two additional steel balls were used as reference markers. A purpose-designed skullholder was made to assure a firm and reproducible positioning of the skulls in the cephalostat. Six series of cephalograms were recorded. One reference series with all the steel balls, four series each with a single steel ball marker removed, one at a time, from each jaw and one series with all the steel ball markers removed, except the reference markers. The combined method error in relocating and replacing the steel ball markers, repositioning the skulls into the skull holder, and digitizing, was low. From the first series, the true position of the palatal plane (NL), the maxillary incisor line (ILs), the mandibular plane (ML) and the mandibular incisor line (ILi) were assessed. From series 2 to 5, each of the landmarks without the steel ball markers was estimated. The accuracy of each landmark was then assessed relative to the true cephalometric plane and its perpendicular. On average, the accuracy was high for all the landmarks except posterior nasal spine (PNS), which was estimated 1.2 mm too far anteriorly (p accuracy of the dental and skeletal landmarks were similar, being 1.4 to 2.4 mm. The maxillary incisors were proclined 1.1 degrees (p < 0.05) by the estimates of incision superior (Is).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7977189

  8. Validation of simple quantification methods for 18F FP CIT PET Using Automatic Delineation of volumes of interest based on statistical probabilistic anatomical mapping and isocontour margin setting

    18F FP CIT positron emission tomography (PET) is an effective imaging for dopamine transporters. In usual clinical practice, 18F FP CIT PET is analyzed visually or quantified using manual delineation of a volume of interest (VOI) fir the stratum. in this study, we suggested and validated two simple quantitative methods based on automatic VOI delineation using statistical probabilistic anatomical mapping (SPAM) and isocontour margin setting. Seventy five 18F FP CIT images acquired in routine clinical practice were used for this study. A study-specific image template was made and the subject images were normalized to the template. afterwards, uptakes in the striatal regions and cerebellum were quantified using probabilistic VOI based on SPAM. A quantitative parameter, QSPAM, was calculated to simulate binding potential. additionally, the functional volume of each striatal region and its uptake were measured in automatically delineated VOI using isocontour margin setting. Uptake volume product(QUVP) was calculated for each striatal region. QSPAMand QUVPwas calculated for each visual grading and the influence of cerebral atrophy on the measurements was tested. Image analyses were successful in all the cases. Both the QSPAMand QUVPwere significantly different according to visual grading (0.001). The agreements of QUVPand QSPAMwith visual grading were slight to fair for the caudate nucleus (K= 0.421 and 0.291, respectively) and good to prefect to the putamen (K=0.663 and 0.607, respectively). Also, QSPAMand QUVPhad a significant correlation with each other (0.001). Cerebral atrophy made a significant difference in QSPAMand QUVPof the caudate nuclei regions with decreased 18F FP CIT uptake. Simple quantitative measurements of QSPAMand QUVPshowed acceptable agreement with visual grad-ing. although QSPAMin some group may be influenced by cerebral atrophy, these simple methods are expected to be effective in the quantitative analysis of F FP CIT PET in usual clinical

  9. A Landmark-Free Method for Three-Dimensional Shape Analysis.

    Benjamin J Pomidor

    Full Text Available The tools and techniques used in morphometrics have always aimed to transform the physical shape of an object into a concise set of numerical data for mathematical analysis. The advent of landmark-based morphometrics opened new avenues of research, but these methods are not without drawbacks. The time investment required of trained individuals to accurately landmark a data set is significant, and the reliance on readily-identifiable physical features can hamper research efforts. This is especially true of those investigating smooth or featureless surfaces.In this paper, we present a new method to perform this transformation for data obtained from high-resolution scanning technology. This method uses surface scans, instead of landmarks, to calculate a shape difference metric analogous to Procrustes distance and perform superimposition. This is accomplished by building upon and extending the Iterative Closest Point algorithm. We also explore some new ways this data can be used; for example, we can calculate an averaged surface directly and visualize point-wise shape information over this surface. Finally, we briefly demonstrate this method on a set of primate skulls and compare the results of the new methodology with traditional geometric morphometric analysis.

  10. Transoral Surgery: An Anatomic Study

    Rock, Jack P.; Tomecek, Frank J.; Ross, Lawrence

    1993-01-01

    The transoral approaches have become commonplace in modern neurosurgical practice for treatment of ventral midline lesions of the clivus and upper cervical spine. Although the standard technique of transoral surgery is conceptually simple, anatomic relationships are not so readily appreciated. The present study was undertaken in an effort to define more clearly the midline anatomic relationships as they pertain to the standard transoral and transpalatine operations. The anatomic relationships...

  11. Delivering high-resolution landmarks using inkjet micropatterning for spatial monitoring of leaf expansion

    Cronk Quentin CB

    2011-01-01

    Full Text Available Abstract Background Inkjet micropatterning is a versatile deposition technique with broad applications in numerous fields. However, its application in plant science is largely unexplored. Leaf expansion is one of the most important parameters in the field of plant science and many methods have been developed to examine differential expansion rates of different parts of the leaf lamina. Among them, methods based on the tracking of natural landmarks through digital imaging require a complicated setup in which the leaf must remain fixed and under tension. Furthermore, the resolution is limited to that of the natural landmarks, which are often difficult to find, particularly in young leaves. To study the fine scale expansion dynamics of the leaf lamina using artificial landmarks it is necessary to place small, noninvasive marks on a leaf surface and then recover the location of those marks after a period of time. Results To monitor leaf expansion in two dimensions, at very fine scales, we used a custom designed inkjet micropatterning system to print a grid composed of c. 0.19 mm2 cells on small developing leaves of ivy (Hedera helix using 40 μm dots at a spacing of c. 91 μm. The leaves in different growing stages were imaged under magnification to extract the coordinates of the marks which were then used in subsequent computer-assisted leaf expansion analyses. As an example we obtained quantified global and local expansion information and created expansion maps over the entire leaf surface. The results reveal a striking pattern of fine-scale expansion differences over short periods of time. In these experiments, the base of the leaf is a "cold spot" for expansion, while the leaf sinuses are "hot spots" for expansion. We have also measured a strong shading effect on leaf expansion. We discuss the features required to build an inkjet printing apparatus optimized for use in plant science, which will further maximize the range of tissues that can be

  12. Impact of daily anatomical changes on EPID-based in vivo dosimetry of VMAT treatments of head-and-neck cancer

    Background and purpose: Target dose verification for VMAT treatments of head-and-neck (H&N) cancer using 3D in vivo EPID dosimetry is expected to be affected by daily anatomical changes. By including these anatomical changes through cone-beam CT (CBCT) information, the magnitude of this effect is investigated. Materials and methods: For 20 VMAT-treated H&N cancer patients, all plan-CTs (pCTs), 633 CBCTs and 1266 EPID movies were used to compare four dose distributions per fraction: treatment planning system (TPS) calculated dose and EPID reconstructed in vivo dose, both determined using the pCT and using the CBCT. D2, D50 and D98 of the planning target volume (PTV) were determined per dose distribution. Results: When including daily anatomical information, D2, D50 and D98 of the PTV change on average by 0.0 ± 0.4% according to TPS calculations; the standard deviation of the difference between EPID and TPS target dose changes from 2.5% (pCT) to 2.1% (CBCT). Small time trends are seen for both TPS and EPID dose distributions when using the pCT, which disappear when including CBCT information. Conclusions: Daily anatomical changes hardly influence the target dose distribution for H&N VMAT treatments according to TPS recalculations. Including CBCT information in EPID dose reconstructions slightly improves the agreement with TPS calculations

  13. Automated extraction of skeletal muscles from torso X-ray CT images based on anatomical positional information between skeleton and skeletal muscles

    We propose an automated approach to extract skeletal muscles in torso X-ray CT images. It transforms 3-D anatomy into 2-D stretched images for simplifying anatomical relationships to getting pathognomonical points. The experimental results show that the proposed method was effective to extract skeletal muscles. (author)

  14. 36 CFR 65.4 - National Historic Landmark criteria.

    2010-07-01

    ... yield information of major scientific importance by revealing new cultures, or by shedding light upon... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false National Historic Landmark... United States in history, architecture, archeology, engineering and culture and that possess a...

  15. An Adaptive Algorithm for Finding Frequent Sets in Landmark Windows

    Dang, Xuan-Hong; Ong, Kok-Leong; Lee, Vincent

    2012-01-01

    We consider a CPU constrained environment for finding approximation of frequent sets in data streams using the landmark window. Our algorithm can detect overload situations, i.e., breaching the CPU capacity, and sheds data in the stream to “keep up”. This is done within a controlled error threshold...

  16. Navigating virtual mazes : The benefits of audiovisual landmarks

    Werkhoven, P.; Erp, J.B.F. van; Philippi, T.G.

    2014-01-01

    It has been shown that multisensory presentation can improve perception, attention, and object memory compared with unisensory presentation. Consequently, we expect that multisensory presentation of landmarks can improve spatial memory and navigation. In this study we tested the effect of visual, au

  17. Audiovisual navigation in virtual mazes : The benefits of audiovisual landmarks

    Werkhoven, Peter; Philippi, Tom; van Erp, J.B.F.

    2014-01-01

    It has been shown that multisensory presentation can improve perception, attention, and object memory compared with unisensory presentation. Consequently, we expect that multisensory presentation of landmarks can improve spatial memory and navigation. In this study we tested the effect of visual, au

  18. Development of IDL-based software for multimodal image registration

    Image registration with anatomical modalities such as CT and MRI, facilitates the anatomical localization in the interpretation of nuclear medicine images, which are relatively lacking in anatomical information. User-friendly program for image registration and fusion of registered images was developed. In consideration of easy transplantation to various operating systems (OS), the program was developed using IDL language. For the registration without operator's interaction, several automatic algorithms were implemented, which include principal axes matching and maximization of mutual information methods. User interface was designed to support the manual registration using point landmarks and the correction for unwanted mis-registration. Fused images were composed by overlaying one image with the other one transparently, in which the opacity of overlaid image was interactively controlled. OS and platform independent program for image registration was developed based on IDL language. It will be useful for the clinical application of image registration techniques

  19. The anatomical basis and prevention of neurogenic voiding dysfunction following radical hysterectomy.

    Tong, X K; Huo, R J

    1991-01-01

    The disorder of neurogenic dysfunction is one of the most important complications of radical hysterectomy. In order to prevent this potential complication, the authors have studied the composition and layers of the pelvic paravisceral structures. The nerve branching and distribution of the pelvic plexus of 12 adult female cadavers were analyzed. From lateral to medial the pelvic paravisceral structure is made up of three layers. The lateral layer is the pelvic visceral fascia, the middle, a vascular layer, and the medial one, a nervous one which consists of the pelvic plexus and subsidiary plexuses. The pelvic plexus and subsidiary plexuses are laid closely to the lateral walls of pelvic organs. The ischial spine was taken as the central point and two perpendicular lines penetrating through the ischial spine were used as the longitudinal axis and transverse axis. According to these landmarks, the pelvic plexus could be divided into three parts: behind the longitudinal axis are the roots of the pelvic plexus, near the longitudinal axis is the uterovaginal plexus, and in front of the longitudinal axis are the branches distributed to bladder and urethra. The pelvic plexus and the uterosacral and cardinal ligaments are closely related. The pelvic and subsidiary plexuses can be damaged in radical hysterectomy and voiding dysfunction may then develop. Some anatomic bases are provided to explain and hopefully prevent this from happening. PMID:1925917

  20. Standardized anatomic space for abdominal fat quantification

    Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.

    2014-03-01

    The ability to accurately measure subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) from images is important for improved assessment and management of patients with various conditions such as obesity, diabetes mellitus, obstructive sleep apnea, cardiovascular disease, kidney disease, and degenerative disease. Although imaging and analysis methods to measure the volume of these tissue components have been developed [1, 2], in clinical practice, an estimate of the amount of fat is obtained from just one transverse abdominal CT slice typically acquired at the level of the L4-L5 vertebrae for various reasons including decreased radiation exposure and cost [3-5]. It is generally assumed that such an estimate reliably depicts the burden of fat in the body. This paper sets out to answer two questions related to this issue which have not been addressed in the literature. How does one ensure that the slices used for correlation calculation from different subjects are at the same anatomic location? At what anatomic location do the volumes of SAT and VAT correlate maximally with the corresponding single-slice area measures? To answer these questions, we propose two approaches for slice localization: linear mapping and non-linear mapping which is a novel learning based strategy for mapping slice locations to a standardized anatomic space so that same anatomic slice locations are identified in different subjects. We then study the volume-to-area correlations and determine where they become maximal. We demonstrate on 50 abdominal CT data sets that this mapping achieves significantly improved consistency of anatomic localization compared to current practice. Our results also indicate that maximum correlations are achieved at different anatomic locations for SAT and VAT which are both different from the L4-L5 junction commonly utilized.

  1. Anatomical study of spinal accessory nerve using ultrasonography

    Canella, Clarissa [Service de Radiologie et d’Imagerie Musculosquelettique, Centre de Consultations et d’Imagerie de l’Appareil Locomoteur, CHRU, 59037, Lille (France); Serviço de Radiologia e Diagnostico por Imagem, Universitadade Federal do Rio de Janeiro, Rio de janeiro (Brazil); Demondion, Xavier [Service de Radiologie et d’Imagerie Musculosquelettique, Centre de Consultations et d’Imagerie de l’Appareil Locomoteur, CHRU, 59037, Lille (France); Laboratoire d’Anatomie, Faculté de Médecine de Lille, 59037, Lille (France); Abreu, Evandro [Service de Radiologie et d’Imagerie Musculosquelettique, Centre de Consultations et d’Imagerie de l’Appareil Locomoteur, CHRU, 59037, Lille (France); Marchiori, Edson [Serviço de Radiologia e Diagnostico por Imagem, Universitadade Federal do Rio de Janeiro, Rio de janeiro (Brazil); Cotten, Hervé [Anatomie et cytologie pathologiques, Bd de la Liberté, 59000, Lille (France); Cotten, Anne, E-mail: anne.cotten@chru-lille.fr [Service de Radiologie et d’Imagerie Musculosquelettique, Centre de Consultations et d’Imagerie de l’Appareil Locomoteur, CHRU, 59037, Lille (France)

    2013-01-15

    Objective: The purpose of our study was to demonstrate that ultrasonography may allow a precise assessment of the course and relationships of the spinal accessory nerve (SAN). Material and methods: This study, initially undertaken in 7 cadavers, was followed by high-resolution ultrasonographic study in 15 volunteers (30 nerves) by two radiologists in consensus. The location, course and relations to the adjacent anatomic structures of the SAN were analyzed. Results: The precise course of the SAN between the lateroposterior border of the sternocleidomastoid muscle and the anterior border of the trapezius muscle could be identified by high-resolution ultrasonography. In contrast, clinical bone landmarks were not found helpful for the identification of the nerve. Conclusion: The SAN can be clearly depicted by means of ultrasonography. Knowledge of the nerve's precise location, which may evidence individual variations, may have useful clinical applications.

  2. Anatomical study of spinal accessory nerve using ultrasonography

    Objective: The purpose of our study was to demonstrate that ultrasonography may allow a precise assessment of the course and relationships of the spinal accessory nerve (SAN). Material and methods: This study, initially undertaken in 7 cadavers, was followed by high-resolution ultrasonographic study in 15 volunteers (30 nerves) by two radiologists in consensus. The location, course and relations to the adjacent anatomic structures of the SAN were analyzed. Results: The precise course of the SAN between the lateroposterior border of the sternocleidomastoid muscle and the anterior border of the trapezius muscle could be identified by high-resolution ultrasonography. In contrast, clinical bone landmarks were not found helpful for the identification of the nerve. Conclusion: The SAN can be clearly depicted by means of ultrasonography. Knowledge of the nerve's precise location, which may evidence individual variations, may have useful clinical applications

  3. Improving anatomical mapping of complexly deformed anatomy for external beam radiotherapy and brachytherapy dose accumulation in cervical cancer

    Purpose: In the treatment of cervical cancer, large anatomical deformations, caused by, e.g., tumor shrinkage, bladder and rectum filling changes, organ sliding, and the presence of the brachytherapy (BT) applicator, prohibit the accumulation of external beam radiotherapy (EBRT) and BT dose distributions. This work proposes a structure-wise registration with vector field integration (SW+VF) to map the largely deformed anatomies between EBRT and BT, paving the way for 3D dose accumulation between EBRT and BT. Methods: T2w-MRIs acquired before EBRT and as a part of the MRI-guided BT procedure for 12 cervical cancer patients, along with the manual delineations of the bladder, cervix-uterus, and rectum-sigmoid, were used for this study. A rigid transformation was used to align the bony anatomy in the MRIs. The proposed SW+VF method starts by automatically segmenting features in the area surrounding the delineated organs. Then, each organ and feature pair is registered independently using a feature-based nonrigid registration algorithm developed in-house. Additionally, a background transformation is calculated to account for areas far from all organs and features. In order to obtain one transformation that can be used for dose accumulation, the organ-based, feature-based, and the background transformations are combined into one vector field using a weighted sum, where the contribution of each transformation can be directly controlled by its extent of influence (scope size). The optimal scope sizes for organ-based and feature-based transformations were found by an exhaustive analysis. The anatomical correctness of the mapping was independently validated by measuring the residual distances after transformation for delineated structures inside the cervix-uterus (inner anatomical correctness), and for anatomical landmarks outside the organs in the surrounding region (outer anatomical correctness). The results of the proposed method were compared with the results of the

  4. Improving anatomical mapping of complexly deformed anatomy for external beam radiotherapy and brachytherapy dose accumulation in cervical cancer

    Vásquez Osorio, Eliana M., E-mail: e.vasquezosorio@erasmusmc.nl; Kolkman-Deurloo, Inger-Karine K.; Schuring-Pereira, Monica; Zolnay, András; Heijmen, Ben J. M.; Hoogeman, Mischa S. [Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam 3075 (Netherlands)

    2015-01-15

    Purpose: In the treatment of cervical cancer, large anatomical deformations, caused by, e.g., tumor shrinkage, bladder and rectum filling changes, organ sliding, and the presence of the brachytherapy (BT) applicator, prohibit the accumulation of external beam radiotherapy (EBRT) and BT dose distributions. This work proposes a structure-wise registration with vector field integration (SW+VF) to map the largely deformed anatomies between EBRT and BT, paving the way for 3D dose accumulation between EBRT and BT. Methods: T2w-MRIs acquired before EBRT and as a part of the MRI-guided BT procedure for 12 cervical cancer patients, along with the manual delineations of the bladder, cervix-uterus, and rectum-sigmoid, were used for this study. A rigid transformation was used to align the bony anatomy in the MRIs. The proposed SW+VF method starts by automatically segmenting features in the area surrounding the delineated organs. Then, each organ and feature pair is registered independently using a feature-based nonrigid registration algorithm developed in-house. Additionally, a background transformation is calculated to account for areas far from all organs and features. In order to obtain one transformation that can be used for dose accumulation, the organ-based, feature-based, and the background transformations are combined into one vector field using a weighted sum, where the contribution of each transformation can be directly controlled by its extent of influence (scope size). The optimal scope sizes for organ-based and feature-based transformations were found by an exhaustive analysis. The anatomical correctness of the mapping was independently validated by measuring the residual distances after transformation for delineated structures inside the cervix-uterus (inner anatomical correctness), and for anatomical landmarks outside the organs in the surrounding region (outer anatomical correctness). The results of the proposed method were compared with the results of the

  5. A New 2D Corner Detector for Extracting Landmarks from Brain MR Images

    Mohammadi, Gelareh; Fatemizadeh, Emad

    2007-01-01

    Point-based registration of images strongly depends on the extraction of suitable landmarks. Recently, various 2D operators have been proposed for the detection of corner points but most of them are not effective for medical images that need a high accuracy. In this paper we have proposed a new automatic corner detector based on the covariance between the small region of support around a central pixel and its rotated one. The main goal of this paper is medical images so we especially focus on...

  6. Solving small spaces: investigating the use of landmark cues in brown capuchins (Cebus apella).

    Hughes, Kelly D; Mullo, Enma; Santos, Laurie R

    2013-09-01

    Some researchers have recently argued that humans may be unusual among primates in preferring to use landmark information when reasoning about some kinds of spatial problems. Some have explained this phenomenon by positing that our species' tendency to prefer landmarks stems from a human-unique trait: language. Here, we test this hypothesis-that preferring to use landmarks to solve such tasks is related to language ability-by exploring landmark use in a spatial task in one non-human primate, the brown capuchin monkey (Cebus apella). We presented our subjects with the rotational displacement task, in which subjects attempt to relocate a reward hidden within an array of hiding locations which are subsequently rotated to a new position. Over several experiments, we varied the availability and the salience of a landmark cue within the array. Specifically, we varied (1) visual access to the array during rotation, (2) the type of landmark, (3) the consistency of the landmark qualities, and (4) the amount of exposure to the landmark. Across Experiments 1 through 4, capuchins did not successfully use landmarks cues, suggesting that non-linguistic primates may not spontaneously use landmarks to solve some spatial problems, as in this case of a small-scale dynamic spatial task. Importantly, we also observed that capuchins demonstrated some capacity to learn to use landmarks in Experiment 4, suggesting that non-linguistic creatures may be able to use some landmarks cues in similar spatial tasks with extensive training. PMID:23430144

  7. Audible Signage as a Wayfinding Aid: Verbal Landmark versus Talking Signs.

    Bentzen, B. L.; Mitchell, P. A.

    1995-01-01

    Comparison by 40 users of 2 technologies--Verbal Landmark and Talking Signs--that provide speech messages to hand-held receivers for blind travelers found that, on all measures, the Talking Signs system proved superior to the Verbal Landmark system. This was attributed to Verbal Landmark's more cognitively demanding technology. (DB)

  8. Slice-based supine-to-standing posture deformation for chinese anatomical models and the dosimetric results with wide band frequency electromagnetic field exposure: Simulation

    Standing Chinese adult anatomical models are obtained from supine-postured cadaver slices. This paper presents the dosimetric differences between the supine and the standing postures over wide band frequencies and various incident configurations. Both the body level and the tissue/organ level differences are reported for plane wave and the 3T magnetic resonance imaging radiofrequency electromagnetic field exposure. The influence of posture on the whole body specific absorption rate and tissue specified specific absorption rate values is discussed. . (authors)

  9. Towards anatomic scale agent-based modeling with a massively parallel spatially explicit general-purpose model of enteric tissue (SEGMEnT_HPC.

    Robert Chase Cockrell

    Full Text Available Perhaps the greatest challenge currently facing the biomedical research community is the ability to integrate highly detailed cellular and molecular mechanisms to represent clinical disease states as a pathway to engineer effective therapeutics. This is particularly evident in the representation of organ-level pathophysiology in terms of abnormal tissue structure, which, through histology, remains a mainstay in disease diagnosis and staging. As such, being able to generate anatomic scale simulations is a highly desirable goal. While computational limitations have previously constrained the size and scope of multi-scale computational models, advances in the capacity and availability of high-performance computing (HPC resources have greatly expanded the ability of computational models of biological systems to achieve anatomic, clinically relevant scale. Diseases of the intestinal tract are exemplary examples of pathophysiological processes that manifest at multiple scales of spatial resolution, with structural abnormalities present at the microscopic, macroscopic and organ-levels. In this paper, we describe a novel, massively parallel computational model of the gut, the Spatially Explicitly General-purpose Model of Enteric Tissue_HPC (SEGMEnT_HPC, which extends an existing model of the gut epithelium, SEGMEnT, in order to create cell-for-cell anatomic scale simulations. We present an example implementation of SEGMEnT_HPC that simulates the pathogenesis of ileal pouchitis, and important clinical entity that affects patients following remedial surgery for ulcerative colitis.

  10. Registration now open for landmark CERN conference

    2003-01-01

    Journalist registration is now available for the Role of Science in the Information Society (RSIS) conference, to be held at CERN on 8-9 December....RSIS will explore future contributions of science to the information society based on past and present practice (1 page).

  11. UAV Control on the Basis of 3D Landmark Bearing-Only Observations

    Karpenko, Simon; Konovalenko, Ivan; Miller, Alexander; Miller, Boris; Nikolaev, Dmitry

    2015-01-01

    The article presents an approach to the control of a UAV on the basis of 3D landmark observations. The novelty of the work is the usage of the 3D RANSAC algorithm developed on the basis of the landmarks’ position prediction with the aid of a modified Kalman-type filter. Modification of the filter based on the pseudo-measurements approach permits obtaining unbiased UAV position estimation with quadratic error characteristics. Modeling of UAV flight on the basis of the suggested algorithm shows good performance, even under significant external perturbations. PMID:26633394

  12. A Stochastic Approach to Diffeomorphic Point Set Registration with Landmark Constraints.

    Kolesov, Ivan; Lee, Jehoon; Sharp, Gregory; Vela, Patricio; Tannenbaum, Allen

    2016-02-01

    This work presents a deformable point set registration algorithm that seeks an optimal set of radial basis functions to describe the registration. A novel, global optimization approach is introduced composed of simulated annealing with a particle filter based generator function to perform the registration. It is shown how constraints can be incorporated into this framework. A constraint on the deformation is enforced whose role is to ensure physically meaningful fields (i.e., invertible). Further, examples in which landmark constraints serve to guide the registration are shown. Results on 2D and 3D data demonstrate the algorithm's robustness to noise and missing information. PMID:26761731

  13. Undecidability and temporal logic: some landmarks from Turing to the present

    Goranko, Valentin

    2012-01-01

    This is a selective survey and discussion of some of the landmark undecidability results in temporal logic, beginning with Turing's undecidability of the Halting problem which, in retrospect, can be regarded as the historically first undecidability result for a suitable temporal logic over...... configuration graphs of Turing machines. I will discuss some of the natural habitats of undecidable temporal logics, such as first-order, interval-based and real time temporal logics, as well as some extensions that often lead to undecidability, such as two-dimensional temporal logics and temporal...

  14. MR neurography with multiplanar reconstruction of 3D MRI datasets: an anatomical study and clinical applications

    Freund, Wolfgang; Aschoff, Andrik J.; Stuber, Gregor; Schmitz, Bernd [University Hospitals Ulm, Clinic for Diagnostic and Interventional Radiology, Ulm (Germany); Brinkmann, Alexander; Wagner, Florian; Dinse, Alexander [University Hospitals Ulm, Department of Anesthesiology, Ulm (Germany)

    2007-04-15

    Extracranial MR neurography has so far mainly been used with 2D datasets. We investigated the use of 3D datasets for peripheral neurography of the sciatic nerve. A total of 40 thighs (20 healthy volunteers) were examined with a coronally oriented magnetization-prepared rapid acquisition gradient echo sequence with isotropic voxels of 1 x 1 x 1 mm and a field of view of 500 mm. Anatomical landmarks were palpated and marked with MRI markers. After MR scanning, the sciatic nerve was identified by two readers independently in the resulting 3D dataset. In every volunteer, the sciatic nerve could be identified bilaterally over the whole length of the thigh, even in areas of close contact to isointense muscles. The landmark of the greater trochanter was falsely palpated by 2.2 cm, and the knee joint by 1 cm. The mean distance between the bifurcation of the sciatic nerve and the knee-joint gap was 6 cm ({+-}1.8 cm). The mean results of the two readers differed by 1-6%. With the described method of MR neurography, the sciatic nerve was depicted reliably and objectively in great anatomical detail over the whole length of the thigh. Important anatomical information can be obtained. The clinical applications of MR neurography for the brachial plexus and lumbosacral plexus/sciatic nerve are discussed. (orig.)

  15. Visual EKF-SLAM from Heterogeneous Landmarks

    Jorge Othón Esparza-Jiménez; Michel Devy; Gordillo, José L.

    2016-01-01

    Many applications require the localization of a moving object, e.g., a robot, using sensory data acquired from embedded devices. Simultaneous localization and mapping from vision performs both the spatial and temporal fusion of these data on a map when a camera moves in an unknown environment. Such a SLAM process executes two interleaved functions: the front-end detects and tracks features from images, while the back-end interprets features as landmark observations and estimates both the land...

  16. The influence of off-screen landmarks on user orientation

    Korda, Amichai

    2014-01-01

    Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies. Maps displayed on hand held devices, such as smartphones; provide limited visibility due to their small screen display. In order to overcome display limitations, researchers have developed new techniques that point users to objects and landmarks located off-screen, which is known as an “off-screen interface”. Since this is a new type of map interface, there is l...

  17. Insite: Canada's landmark safe injecting program at risk

    Drucker Ernest

    2006-01-01

    Abstract InSite is North Americas first supervised injection site and a landmark public heath initiative operating in Vancouver since 2003. The program is a vital component of that cities internationally recognized harm reduction approach to its serious problems with drugs, crime, homelessness and AIDS. InSite currently operates under a waiver of Federal rules that allow it to provide services as a research project. An extensive evaluation has produced very positive results for thousands of u...

  18. Visual landmarks facilitate rodent spatial navigation in virtual reality environments

    Youngstrom, Isaac A.; Strowbridge, Ben W.

    2012-01-01

    Because many different sensory modalities contribute to spatial learning in rodents, it has been difficult to determine whether spatial navigation can be guided solely by visual cues. Rodents moving within physical environments with visual cues engage a variety of nonvisual sensory systems that cannot be easily inhibited without lesioning brain areas. Virtual reality offers a unique approach to ask whether visual landmark cues alone are sufficient to improve performance in a spatial task. We ...

  19. Automatic Registration and Error Detection of Multiple Slices Using Landmarks

    Frimmel, Hans; Egevad, Lars; Busch, Christer; Bengtsson, Ewert

    2001-01-01

    Objectives. When analysing the 3D structure of tissue, serial sectioning and staining of the resulting slices is sometimes the preferred option. This leads to severe registration problems. In this paper, a method for automatic registration and error detection of slices using landmark needles has been developed. A cost function takes some parameters from the current state of the problem to be solved as input and gives a quality of the current solution as output. The cost function used in this ...

  20. AUTOMATIC DETECTION AND CLASSIFICATION OF RETINAL VASCULAR LANDMARKS

    Hadi Hamad

    2014-06-01

    Full Text Available The main contribution of this paper is introducing a method to distinguish between different landmarks of the retina: bifurcations and crossings. The methodology may help in differentiating between arteries and veins and is useful in identifying diseases and other special pathologies, too. The method does not need any special skills, thus it can be assimilated to an automatic way for pinpointing landmarks; moreover it gives good responses for very small vessels. A skeletonized representation, taken out from the segmented binary image (obtained through a preprocessing step, is used to identify pixels with three or more neighbors. Then, the junction points are classified into bifurcations or crossovers depending on their geometrical and topological properties such as width, direction and connectivity of the surrounding segments. The proposed approach is applied to the public-domain DRIVE and STARE datasets and compared with the state-of-the-art methods using proper validation parameters. The method was successful in identifying the majority of the landmarks; the average correctly identified bifurcations in both DRIVE and STARE datasets for the recall and precision values are: 95.4% and 87.1% respectively; also for the crossovers, the recall and precision values are: 87.6% and 90.5% respectively; thus outperforming other studies.

  1. ANATOMICAL PROPERTIES OF PLANTAGO ARENARIA

    Nicoleta IANOVICI; SINITEAN, Adrian; Aurel FAUR

    2011-01-01

    Psammophytes are marked by a number of adaptations that enable them to exist in the hard environmental conditions of the sand habitats. In this study, the anatomical characteristics of Plantago arenaria were examined. Studies were conducted to assess the diversity of anatomical adaptations of vegetative organs in this taxa. Results are presented with original photographs. The analysis of leaf anatomy in P. arenaria showed that the leaves contained a contained xeromorphic traits. Arbuscular my...

  2. 基于地标点几何形态测量法识别北部湾4种白姑鱼矢耳石形态%Using landmark-based geometric morphometrics analysis to identify sagittal otolith of four Pennahia fish species

    侯刚; 刘丹丹; 冯波; 卢伙胜

    2013-01-01

    We investigated the identification in sagittal otoliths using landmark-based geometric morphometrics method among four sympatric species of the genus Pennahia: truncatetail white croaker P.anea (n=49), bighead white croaker P.macrocephalus (n=50), pawak croaker P. pawak (n=49) and white croaker P.argentata (n=29).The specimens were collected off Beibu Gulf from April 2010 to October 2010. Landmark coordinate values were extracted after otolith digitized by image processing and processed by relative warp principal component (RW), thin plate spline analysis and grad distortion. The 12 RW were then identified using discrimination analysis to differentiate the otoliths of four Pennahia species. The result indicated that, the 1st, 2nd and 3rd RW accounted for 46.57%, 25.39% and 10.02% of the total variation respectively, of which TypeⅠlandmarks 6 and 7, TypeⅡlandmarks 5 and 8 had important contributions, and could explain the most variation. The most morphological variation were displayed in neck, head width pole, and tail of tadpole-shaped sulcus. The gradual discrimination analysis and cross validation indicated that P.anea, P.macrocephalus and P. pawak got average exactitude distinguish ratios of 81.6%~100%, while P.argentata 58.6%, indicating that it contained a potential risk by using the morphology of tadpole-shaped impression owned by Sciaenidae to discriminate the four congeneric Pennahia species. It is necessary to notice this problem in the related otolith morphology research and application in feeding ecology.%利用2010年4月至2010年10月采自北部湾海域的49尾截尾白姑鱼(Pennahia anea)、50尾大头白姑鱼(P. macrocephalus)、49尾斑鳍白姑鱼(P. pawak )和29尾白姑鱼(P.argentata)矢耳石样本,运用基于地标点法的几何形态测量学方法研究了4种鱼类矢耳石形态识别问题。耳石经图像处理后提取地标点坐标值,进行相对扭曲主成分分析,通过判别分析来区分4种白姑鱼的耳石,

  3. Integrating anatomical pathology to the healthcare enterprise.

    Daniel-Le Bozec, Christel; Henin, Dominique; Fabiani, Bettina; Bourquard, Karima; Ouagne, David; Degoulet, Patrice; Jaulent, Marie-Christine

    2006-01-01

    For medical decisions, healthcare professionals need that all required information is both correct and easily available. We address the issue of integrating anatomical pathology department to the healthcare enterprise. The pathology workflow from order to report, including specimen process and image acquisition was modeled. Corresponding integration profiles were addressed by expansion of the IHE (Integrating the Healthcare Enterprise) initiative. Implementation using respectively DICOM Structured Report (SR) and DICOM Slide-Coordinate Microscopy (SM) was tested. The two main integration profiles--pathology general workflow and pathology image workflow--rely on 13 transactions based on HL7 or DICOM standard. We propose a model of the case in anatomical pathology and of other information entities (orders, image folders and reports) and real-world objects (specimen, tissue samples, slides, etc). Cases representation in XML schemas, based on DICOM specification, allows producing DICOM image files and reports to be stored into a PACS (Picture Archiving and Communication System. PMID:17108550

  4. Review of the Historical Evolution of Anatomical Terms

    Algieri, Rubén D.

    2011-12-01

    Full Text Available Most of the medical terms of Greek origin are traditionally attributed to Hippocrates (460-370 BC. Claudius Galen of Pergamum (130-200 BC developed a classification of bones and joints and described different brain areas. His teachings have remained unchanged for over a thousand years. Andreas Vesalius of Brussels (1514-1564, through the systematic study of human body structure, changed many concepts. He published his work in his production "De humani corporis fabrica libri septem", where a special attention is evident to the discovery and description of new anatomical facts. From here there is a revolution in the morphological sciences, where the same anatomical structure passed to receive different names. In the nineteenth century, the different anatomists in the world decide to meet in order to unify criteria regarding the anatomical structures and determine a only one universal language in the anatomical sciences. In 1895, in Basel (Switzerland it’s approved a list of 5.573 terms, called Basle Nomina Anatomica (BNA and was written in Latin. Eponyms were deleted. In 1903, he founded the International Federation of Associations of anatomists (IFAA. In 1935, in Jena (Germany, approving the Jena Nomina Anatomica (JNA. In 1950, in Oxford, formed the Committee of the International Anatomical Nomenclature (IANC. In 1955, in Paris (France it is agreed to adopt a Latin nomenclature based on the BNA, the Paris Nomina Anatomica (PNA. In 1980, for the first time in Latin America, takes place on the 11th International Congress of Anatomists, Mexico. In 1989, the International Committee of Anatomical Nomenclature, published the sixth edition of the Nomina Anatomica, without review by the IFAA. The same year, the latter established a Federative International Committee of Anatomical Terminology (FICAT. In 1998, he published a new list FICAT: International Anatomical Terminology (TAI, with the structures named in Latin language and their equivalence in

  5. Anatomically Plausible Surface Alignment and Reconstruction

    Paulsen, Rasmus R.; Larsen, Rasmus

    2010-01-01

    With the increasing clinical use of 3D surface scanners, there is a need for accurate and reliable algorithms that can produce anatomically plausible surfaces. In this paper, a combined method for surface alignment and reconstruction is proposed. It is based on an implicit surface representation...... energy that has earlier proved to be particularly well suited for human surface scans. The method has been tested on full cranial scans of ten test subjects and on several scans of the outer human ear....

  6. Fusion of WiFi, smartphone sensors and landmarks using the Kalman filter for indoor localization.

    Chen, Zhenghua; Zou, Han; Jiang, Hao; Zhu, Qingchang; Soh, Yeng Chai; Xie, Lihua

    2015-01-01

    Location-based services (LBS) have attracted a great deal of attention recently. Outdoor localization can be solved by the GPS technique, but how to accurately and efficiently localize pedestrians in indoor environments is still a challenging problem. Recent techniques based on WiFi or pedestrian dead reckoning (PDR) have several limiting problems, such as the variation of WiFi signals and the drift of PDR. An auxiliary tool for indoor localization is landmarks, which can be easily identified based on specific sensor patterns in the environment, and this will be exploited in our proposed approach. In this work, we propose a sensor fusion framework for combining WiFi, PDR and landmarks. Since the whole system is running on a smartphone, which is resource limited, we formulate the sensor fusion problem in a linear perspective, then a Kalman filter is applied instead of a particle filter, which is widely used in the literature. Furthermore, novel techniques to enhance the accuracy of individual approaches are adopted. In the experiments, an Android app is developed for real-time indoor localization and navigation. A comparison has been made between our proposed approach and individual approaches. The results show significant improvement using our proposed framework. Our proposed system can provide an average localization accuracy of 1 m. PMID:25569750

  7. Continuous Indoor Positioning Fusing WiFi, Smartphone Sensors and Landmarks.

    Deng, Zhi-An; Wang, Guofeng; Qin, Danyang; Na, Zhenyu; Cui, Yang; Chen, Juan

    2016-01-01

    To exploit the complementary strengths of WiFi positioning, pedestrian dead reckoning (PDR), and landmarks, we propose a novel fusion approach based on an extended Kalman filter (EKF). For WiFi positioning, unlike previous fusion approaches setting measurement noise parameters empirically, we deploy a kernel density estimation-based model to adaptively measure the related measurement noise statistics. Furthermore, a trusted area of WiFi positioning defined by fusion results of previous step and WiFi signal outlier detection are exploited to reduce computational cost and improve WiFi positioning accuracy. For PDR, we integrate a gyroscope, an accelerometer, and a magnetometer to determine the user heading based on another EKF model. To reduce accumulation error of PDR and enable continuous indoor positioning, not only the positioning results but also the heading estimations are recalibrated by indoor landmarks. Experimental results in a realistic indoor environment show that the proposed fusion approach achieves substantial positioning accuracy improvement than individual positioning approaches including PDR and WiFi positioning. PMID:27608019

  8. Continuous Indoor Positioning Fusing WiFi, Smartphone Sensors and Landmarks

    Zhi-An Deng

    2016-09-01

    Full Text Available To exploit the complementary strengths of WiFi positioning, pedestrian dead reckoning (PDR, and landmarks, we propose a novel fusion approach based on an extended Kalman filter (EKF. For WiFi positioning, unlike previous fusion approaches setting measurement noise parameters empirically, we deploy a kernel density estimation-based model to adaptively measure the related measurement noise statistics. Furthermore, a trusted area of WiFi positioning defined by fusion results of previous step and WiFi signal outlier detection are exploited to reduce computational cost and improve WiFi positioning accuracy. For PDR, we integrate a gyroscope, an accelerometer, and a magnetometer to determine the user heading based on another EKF model. To reduce accumulation error of PDR and enable continuous indoor positioning, not only the positioning results but also the heading estimations are recalibrated by indoor landmarks. Experimental results in a realistic indoor environment show that the proposed fusion approach achieves substantial positioning accuracy improvement than individual positioning approaches including PDR and WiFi positioning.

  9. Fusion of WiFi, Smartphone Sensors and Landmarks Using the Kalman Filter for Indoor Localization

    Zhenghua Chen

    2015-01-01

    Full Text Available Location-based services (LBS have attracted a great deal of attention recently. Outdoor localization can be solved by the GPS technique, but how to accurately and efficiently localize pedestrians in indoor environments is still a challenging problem. Recent techniques based on WiFi or pedestrian dead reckoning (PDR have several limiting problems, such as the variation of WiFi signals and the drift of PDR. An auxiliary tool for indoor localization is landmarks, which can be easily identified based on specific sensor patterns in the environment, and this will be exploited in our proposed approach. In this work, we propose a sensor fusion framework for combining WiFi, PDR and landmarks. Since the whole system is running on a smartphone, which is resource limited, we formulate the sensor fusion problem in a linear perspective, then a Kalman filter is applied instead of a particle filter, which is widely used in the literature. Furthermore, novel techniques to enhance the accuracy of individual approaches are adopted. In the experiments, an Android app is developed for real-time indoor localization and navigation. A comparison has been made between our proposed approach and individual approaches. The results show significant improvement using our proposed framework. Our proposed system can provide an average localization accuracy of 1 m.

  10. Hoffa's fat pad injuries and their relationship with anterior cruciate ligament tears: new observations based on MR imaging in patients and MR imaging and anatomic correlation in cadavers

    To determine the normal anatomic relationships of Hoffa's fat pad with the anterior cruciate ligament (ACL) and with the frequency of Hoffa's fat pad abnormalities in ACL-deficient knees. Retrospective clinical study on patients and observational anatomic study on cadavers. The study was approved by the Institutional Review Board. MR imaging studies of the knees of 100 patients (21-48 years old) with or without arthroscopically proven tears of the ACL, performed at a single institution, were reviewed by two readers for abnormalities of Hoffa's fat pad. Ten cadaveric knee specimens were studied with MR imaging and Faxitron radiographs, and by inspection of sections and histology. Alterations in Hoffa's fat pad on MR imaging were present in 64% (32/50) of patients with torn ACLs, and in 24% (12/50) of patients without a tear of the ACL (P < 0.05). Hoffa's fat pad inserted into the intercondylar notch in 50% (5/10) of cadaveric specimens, four in conjunction with the ligamentum mucosum and in one in an isolated fashion. Histological study demonstrated the composition of the ligamentum mucosum and Hoffa's fat pad and their course and insertion sites in the intercondylar notch. Abnormalities of Hoffa's fat pad, such as focal and diffuse edema, tears, scars and synovial proliferation, are more common in knees with torn ACLs than in knees with intact ACLs. (orig.)

  11. Digital 3D anatomical modeling of the mandible with full teeth%数字化全牙列下颌骨三维解剖建模

    朱赴东; 石珏; 宋恩; 葛巍立; 廖胜辉

    2014-01-01

    Objective To study and establish a high quality digital 3D anatomical modeling of the mandible with full teeth.Methods A set of accurate digital models of standard anatomical specimens of mandibular teeth were obtained by laser scanning, and the 3D mandible model was reconstructed by CT scan data;then, a registration deformation method based on the geometry and image anatomical landmark was employed to do the registration of each tooth to the mandible model, and finally the tooth enamel , dentin, periodontal ligament were generated .Results A high quality digital 3D anatomical modeling of the mandible with full teeth was built , each tooth had detail crown and whole root , the distinction between the enamel , dentin, periodontal ligament , and any anatomical regions can be zoomed and rotately displayed . Conclusion The digital 3D anatomical modeling of the mandible with full teeth has realistic 3D imaging view and convenient teaching-learning function , and has tremendous apllication futures in the stomatology , maxillofacial and other medical departments .%目的:探讨建立具有高质量牙列的下颌骨三维数字化解剖模型。方法用激光扫描获取1套标准下颌牙列解剖标本的精确三维模型,用CT扫描数据重建下颌骨三维模型,使用基于几何和图像解剖标志的配准变形方法将每颗牙齿模型对齐融合到下颌骨模型,进一步生成牙齿的牙釉质、牙本质、牙周膜。结果成功建立了具有高质量牙列的下颌骨三维数字化解剖模型,每颗牙齿具有牙冠细节和完整的牙根,区分牙釉质、牙本质、牙周膜,可以对任意解剖区域放大和旋转观察,显示解剖标志。结论高质量牙列的下颌骨三维数字化解剖模型具有逼真的三维显象和方便的教学学习功能,可用于口腔、颌面、解剖等多个学科。

  12. Probabilistic anatomical labeling of brain structures using statistical probabilistic anatomical maps

    The use of statistical parametric mapping (SPM) program has increased for the analysis of brain PET and SPECT images. Montreal neurological institute (MNI) coordinate is used in SPM program as a standard anatomical framework. While the most researchers look up Talairach atlas to report the localization of the activations detected in SPM program, there is significant disparity between MNI templates and Talairach atlas. That disparity between Talairach and MNI coordinates makes the interpretation of SPM result time consuming, subjective and inaccurate. The purpose of this study was to develop a program to provide objective anatomical information of each x-y-z position in ICBM coordinate. Program was designed to provide the anatomical information for the given x-y-z position in MNI coordinate based on the statistical probabilistic anatomical map (SPAM) images of ICBM. When x-y-z position was given to the program, names of the anatomical structures with non-zero probability and the probabilities that the given position belongs to the structures were tabulated. The program was coded using IDL and JAVA language for the easy transplantation to any operating system or platform. Utility of this program was shown by comparing the results of this program to those of SPM program. Preliminary validation study was performed by applying this program to the analysis of PET brain activation study of human memory in which the anatomical information on the activated areas are previously known. Real time retrieval of probabilistic information with 1 mm spatial resolution was archived using the programs. Validation study showed the relevance of this program: probability that the activated area for memory belonged to hippocampal formation was more than 80%. These programs will be useful for the result interpretation of the image analysis performed on MNI coordinate, as done in SPM program

  13. Slice-based supine to standing postured deformation for chinese anatomical models and the dosimetric results by wide band frequency electromagnetic field exposure: Morphing

    Digital human models are frequently obtained from supine-postured medical images or cadaver slices, but many applications require standing models. This paper presents the work of reconstructing standing Chinese adult anatomical models from supine postured slices. Apart from the previous studies, the deformation works on 2-D segmented slices. The surface profile of the standing posture is adjusted by population measurement data. A non-uniform texture amplification approach is applied on the 2-D slices to recover the skin contour and to redistribute the internal tissues. Internal organ shift due to postures is taken into account. The feet are modified by matrix rotation. Then, the supine and standing models are utilised for the evaluation of electromagnetic field exposure over wide band frequency and different incident directions. . (authors)

  14. ANATOMICAL PROPERTIES OF PLANTAGO ARENARIA

    Nicoleta IANOVICI

    2011-01-01

    Full Text Available Psammophytes are marked by a number of adaptations that enable them to exist in the hard environmental conditions of the sand habitats. In this study, the anatomical characteristics of Plantago arenaria were examined. Studies were conducted to assess the diversity of anatomical adaptations of vegetative organs in this taxa. Results are presented with original photographs. The analysis of leaf anatomy in P. arenaria showed that the leaves contained a contained xeromorphic traits. Arbuscular mycorrhizal symbiosis seems to be critical for their survival.

  15. Anatomically Correct Surface Recovery

    Jensen, Rasmus Ramsbøl; Nielsen, Jannik Boll; Larsen, Rasmus;

    2015-01-01

    We present a method for 3D surface recovery in partial surface scans. The method is based on an Active Shape Model, which is used to predict missing data. The model is constructed using a bootstrap framework, where an initially small collection of hand-annotated samples is used to fit to and...

  16. Corner Feature Extraction: Techniques for Landmark Based Navigation Systems

    Namoshe, Molaletsa; Matsebe, Oudetse; Tlale, Nkgatho

    2010-01-01

    In this paper we discussed the results of an EKF SLAM using real data logged and computed offline. One of the most important parts of the SLAM process is to accurately map the environment the robot is exploring and localize in it. To achieve this however, is depended on the precise acquirement of features extracted from the external sensor. We looked at corner detection methods and we proposed an improved version of the method discussed in section 2.1.1. It transpired that methods found in th...

  17. Detection and Analysis of Statistical Differences in Anatomical Shape

    Golland, Polina; Grimson, W. Eric L.; Martha E. Shenton; Kikinis, Ron

    2005-01-01

    We present a computational framework for image-based analysis and interpretation of statistical differences in anatomical shape between populations. Applications of such analysis include understanding developmental and anatomical aspects of disorders when comparing patients vs. normal controls, studying morphological changes caused by aging, or even differences in normal anatomy, for example, differences between genders. Once a quantitative description of organ shape is extracted from input i...

  18. Exploring brain function from anatomical connectivity

    Gorka Zamora-López

    2011-06-01

    Full Text Available The intrinsic relationship between the architecture of the brain and the range of sensory and behavioral phenomena it produces is a relevant question in neuroscience. Here, we review recent knowledge gained on the architecture of the anatomical connectivity by means of complex network analysis. It has been found that corticocortical networks display a few prominent characteristics: (i modular organization, (ii abundant alternative processing paths and (iii the presence of highly connected hubs. Additionally, we present a novel classification of cortical areas of the cat according to the role they play in multisensory connectivity. All these properties represent an ideal anatomical substrate supporting rich dynamical behaviors, as-well-as facilitating the capacity of the brain to process sensory information of different modalities segregated and to integrate them towards a comprehensive perception of the real world. The result here exposed are mainly based in anatomical data of cats’ brain, but we show how further observations suggest that, from worms to humans, the nervous system of all animals might share fundamental principles of organization.

  19. Quantifying anatomical shape variations in neurological disorders.

    Singh, Nikhil; Fletcher, P Thomas; Preston, J Samuel; King, Richard D; Marron, J S; Weiner, Michael W; Joshi, Sarang

    2014-04-01

    We develop a multivariate analysis of brain anatomy to identify the relevant shape deformation patterns and quantify the shape changes that explain corresponding variations in clinical neuropsychological measures. We use kernel Partial Least Squares (PLS) and formulate a regression model in the tangent space of the manifold of diffeomorphisms characterized by deformation momenta. The scalar deformation momenta completely encode the diffeomorphic changes in anatomical shape. In this model, the clinical measures are the response variables, while the anatomical variability is treated as the independent variable. To better understand the "shape-clinical response" relationship, we also control for demographic confounders, such as age, gender, and years of education in our regression model. We evaluate the proposed methodology on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database using baseline structural MR imaging data and neuropsychological evaluation test scores. We demonstrate the ability of our model to quantify the anatomical deformations in units of clinical response. Our results also demonstrate that the proposed method is generic and generates reliable shape deformations both in terms of the extracted patterns and the amount of shape changes. We found that while the hippocampus and amygdala emerge as mainly responsible for changes in test scores for global measures of dementia and memory function, they are not a determinant factor for executive function. Another critical finding was the appearance of thalamus and putamen as most important regions that relate to executive function. These resulting anatomical regions were consistent with very high confidence irrespective of the size of the population used in the study. This data-driven global analysis of brain anatomy was able to reach similar conclusions as other studies in Alzheimer's disease based on predefined ROIs, together with the identification of other new patterns of deformation. The

  20. A cubic B-spline-based hybrid registration of lung CT images for a dynamic airway geometric model with large deformation

    The goal of this study is to develop a matching algorithm that can handle large geometric changes in x-ray computed tomography (CT)-derived lung geometry occurring during deep breath maneuvers. These geometric relationships are further utilized to build a dynamic lung airway model for computational fluid dynamics (CFD) studies of pulmonary air flow. The proposed algorithm is based on a cubic B-spline-based hybrid registration framework that incorporates anatomic landmark information with intensity patterns. A sequence of invertible B-splines is composed in a multiresolution framework to ensure local invertibility of the large deformation transformation and a physiologically meaningful similarity measure is adopted to compensate for changes in voxel intensity due to inflation. Registrations are performed using the proposed approach to match six pairs of 3D CT human lung datasets. Results show that the proposed approach has the ability to match the intensity pattern and the anatomical landmarks, and ensure local invertibility for large deformation transformations. Statistical results also show that the proposed hybrid approach yields significantly improved results as compared with approaches using either landmarks or intensity alone.

  1. A cubic B-spline-based hybrid registration of lung CT images for a dynamic airway geometric model with large deformation

    Yin Youbing; Lin, Ching-Long [Department of Mechanical and Industrial Engineering, University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A [Department of Radiology, University of Iowa, Iowa City, IA 52242 (United States); Ding Kai; Reinhardt, Joseph M, E-mail: ching-long-lin@uiowa.edu [Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242 (United States)

    2011-01-07

    The goal of this study is to develop a matching algorithm that can handle large geometric changes in x-ray computed tomography (CT)-derived lung geometry occurring during deep breath maneuvers. These geometric relationships are further utilized to build a dynamic lung airway model for computational fluid dynamics (CFD) studies of pulmonary air flow. The proposed algorithm is based on a cubic B-spline-based hybrid registration framework that incorporates anatomic landmark information with intensity patterns. A sequence of invertible B-splines is composed in a multiresolution framework to ensure local invertibility of the large deformation transformation and a physiologically meaningful similarity measure is adopted to compensate for changes in voxel intensity due to inflation. Registrations are performed using the proposed approach to match six pairs of 3D CT human lung datasets. Results show that the proposed approach has the ability to match the intensity pattern and the anatomical landmarks, and ensure local invertibility for large deformation transformations. Statistical results also show that the proposed hybrid approach yields significantly improved results as compared with approaches using either landmarks or intensity alone.

  2. APFiLoc: An Infrastructure-Free Indoor Localization Method Fusing Smartphone Inertial Sensors, Landmarks and Map Information

    Jianga Shang

    2015-10-01

    Full Text Available The utility and adoption of indoor localization applications have been limited due to the complex nature of the physical environment combined with an increasing requirement for more robust localization performance. Existing solutions to this problem are either too expensive or too dependent on infrastructure such as Wi-Fi access points. To address this problem, we propose APFiLoc—a low cost, smartphone-based framework for indoor localization. The key idea behind this framework is to obtain landmarks within the environment and to use the augmented particle filter to fuse them with measurements from smartphone sensors and map information. A clustering method based on distance constraints is developed to detect organic landmarks in an unsupervised way, and the least square support vector machine is used to classify seed landmarks. A series of real-world experiments were conducted in complex environments including multiple floors and the results show APFiLoc can achieve 80% accuracy (phone in the hand and around 70% accuracy (phone in the pocket of the error less than 2 m error without the assistance of infrastructure like Wi-Fi access points.

  3. APFiLoc: An Infrastructure-Free Indoor Localization Method Fusing Smartphone Inertial Sensors, Landmarks and Map Information.

    Shang, Jianga; Gu, Fuqiang; Hu, Xuke; Kealy, Allison

    2015-01-01

    The utility and adoption of indoor localization applications have been limited due to the complex nature of the physical environment combined with an increasing requirement for more robust localization performance. Existing solutions to this problem are either too expensive or too dependent on infrastructure such as Wi-Fi access points. To address this problem, we propose APFiLoc-a low cost, smartphone-based framework for indoor localization. The key idea behind this framework is to obtain landmarks within the environment and to use the augmented particle filter to fuse them with measurements from smartphone sensors and map information. A clustering method based on distance constraints is developed to detect organic landmarks in an unsupervised way, and the least square support vector machine is used to classify seed landmarks. A series of real-world experiments were conducted in complex environments including multiple floors and the results show APFiLoc can achieve 80% accuracy (phone in the hand) and around 70% accuracy (phone in the pocket) of the error less than 2 m error without the assistance of infrastructure like Wi-Fi access points. PMID:26516858

  4. Disorientation inhibits landmark use in 12-18-month-old infants.

    Lew, Adina R; Foster, Kirsty A; Bremner, J Gavin

    2006-07-01

    Recent research has indicated that, particularly under conditions of inertial disorientation, mammals may be sensitive to landmark configuration geometry at the expense of individual featural information when locating hidden goals. The current study sought to establish whether landmark use could be demonstrated in 12-18-month-old infants with and without a disorientation procedure, and with geometrically ambiguous landmark configurations. A peekaboo paradigm was employed in which infants learned to anticipate a peekaboo event after a cue from two locations within a circular arena, followed by a test trial from a novel position in which no peekaboo occurred after the cue. In all conditions, an isosceles triangle arrangement of landmarks was used, with peekaboo occurring between the landmarks of one of the two equal "sides", thus being geometrically ambiguous. In two conditions, the landmarks were distinctive, and in two further conditions, they were identical. In one of the distinctive conditions and one of the identical landmark conditions, infants underwent a disorientation procedure in between training and test trials. Only oriented infants with distinctive landmarks were successful in test trials, thus suggesting that infants are able to use the individual features of landmarks to locate a goal, but can only do so if oriented. PMID:17138289

  5. Study on the Construction of a High-definition Whole-body Voxel Model based on Cadaver's Color Photographic Anatomical Slice Images and Monte Carlo Dose Calculations

    Ajou University School of Medicine made the serially sectioned anatomical images from the Visible Korean Human (VKH) Project in Korea. The VKH images, which are the high-resolution color photographic images, show the organs and tissues in the human body very clearly at 0.2 mm intervals. In this study, we constructed a high-quality voxel model (VKH-Man) with a total of 30 organs and tissues by manual and automatic segmentation method using the serially sectioned anatomical image data from the Visible Korean Human (VKH) project in Korea. The height and weight of VKH-Man voxel model is 164 cm and 57.6 kg, respectively, and the voxel resolution is 1.875 x 1.875 x 2 mm3. However, this voxel phantom can be used to calculate the organ and tissue doses of only one person. Therefore, in this study, we adjusted the voxel phantom to the 'Reference Korean' data to construct the voxel phantom that represents the radiation workers in Korea. The height and weight of the voxel model (HDRK-Man) that is finally developed are 171 cm and 68 kg, respectively, and the voxel resolution is 1.981 x 1.981 x 2.0854 mm3. VKH-Man and HDRK-Man voxel model were implemented in a Monte Carlo particle transport simulation code for calculation of the organ and tissue doses in various irradiation geometries. The calculated values were compared with each other to see the effect of the adjustment and also compared with other computational models (KTMAN-2, ICRP-74 and VIP-Man). According to the results, the adjustment of the voxel model was found hardly affect the dose calculations and most of the organ and tissue equivalent doses showed some differences among the models. These results shows that the difference in figure, and organ topology affects the organ doses more than the organ size. The calculated values of the effective dose from VKH-Man and HDRK-Man according to the ICRP-60 and upcoming ICRP recommendation were compared. For the other radiation geometries (AP, LLAT, RLAT) except for PA

  6. Anatomical terminology and nomenclature: past, present and highlights.

    Kachlik, David; Baca, Vaclav; Bozdechova, Ivana; Cech, Pavel; Musil, Vladimir

    2008-08-01

    The anatomical terminology is a base for medical communication. It is elaborated into a nomenclature in Latin. Its history goes back to 1895, when the first Latin anatomical nomenclature was published as Basiliensia Nomina Anatomica. It was followed by seven revisions (Jenaiensia Nomina Anatomica 1935, Parisiensia Nomina Anatomica 1955, Nomina Anatomica 2nd to 6th edition 1960-1989). The last revision, Terminologia Anatomica, (TA) created by the Federative Committee on Anatomical Terminology and approved by the International Federation of Associations of Anatomists, was published in 1998. Apart from the official Latin anatomical terminology, it includes a list of recommended English equivalents. In this article, major changes and pitfalls of the nomenclature are discussed, as well as the clinical anatomy terms. The last revision (TA) is highly recommended to the attention of not only teachers, students and researchers, but also to clinicians, doctors, translators, editors and publishers to be followed in their activities. PMID:18488135

  7. Application of the Restriction Landmark Genome Scanning (RLGS Method for Analysis of Genetic Diversity between Asian and African Sorghum

    Hisato Okuizumi*, Tomotsugu Noguchi, Tatsuya Saguchi,Takuma Fujita, Eri Nonaka, Shinsuke Yamanaka, Koffi Kombate, Subbarayan Sivakumar , Kulandaivelu Ganesamurthy, Yasufumi Murakami

    2010-07-01

    Full Text Available Restriction Landmark Genome Scanning (RLGS used to detect large numbers of restriction landmarks in a single experiment andapplied to analyze the genetic diversity of Asian and African sorghum accessions. This method is one of the genome analysistools based on the concept that restriction enzyme sites can serve as landmarks throughout a genome. RLGS uses direct endlabelingof the genomic DNA digested with a rare-cutting restriction enzyme and high-resolution two-dimensionalelectrophoresis. It has an advantage of providing precise information on a spot intensity that reflects the copy number ofrestriction landmarks and to visualize differences in methylation levels across the genome. RLGS becomes very useful for doingwhole genome scans that equals the work of thousands of polymerase chain reactions. A study was carried out using Sorghumaccessions collected from countries viz., Morocco, Nigeria, Sudan, South Africa, Japan, South Korea, and China. Onerepresentative sample was chosen from a country for analysis carried out at National Institute of Agrobiological Sciences(NIAS. Two dimensional spot images for seven accessions obtained and spot intensities were scanned. Totally, 119 spots weredetected of which 95 spots observed as polymorphic and 24 as non polymorphic. Unique presence and null spots werespecifically detected in all accessions taken for study. A total of 37 unique spots and 12 null spots, detected in this experiment.Principal Coordinate Analysis indicated, four African accessions scattered in the diagram were diverse and three Asianaccessions closely distributed with narrow diversity. The phylogenetic tree showed that Sudan and Nigerian accessions weredistant while Chinna, Japan and Korea accessions had close proximity

  8. Maximized Posteriori Attributes Selection from Facial Salient Landmarks for Face Recognition

    Gupta, Phalguni; Sing, Jamuna Kanta; Tistarelli, Massimo

    2010-01-01

    This paper presents a robust and dynamic face recognition technique based on the extraction and matching of devised probabilistic graphs drawn on SIFT features related to independent face areas. The face matching strategy is based on matching individual salient facial graph characterized by SIFT features as connected to facial landmarks such as the eyes and the mouth. In order to reduce the face matching errors, the Dempster-Shafer decision theory is applied to fuse the individual matching scores obtained from each pair of salient facial features. The proposed algorithm is evaluated with the ORL and the IITK face databases. The experimental results demonstrate the effectiveness and potential of the proposed face recognition technique also in case of partially occluded faces.

  9. Evaluation of association between mandibular crowding and some of anatomical indexes in skeletal Cl II 8-12 years old patient with mandibular deficiency

    Shirazi Mohsen; Darvishpour Hojat; Nateghi Reza; Mirhashemi Amir Hosein; Salari Behzad

    2015-01-01

    Tehran University of Medical Sciences, Tehran, Iran ( )   Background and Aims: Nowadays patients refer to orthodontist for issue such as dental crowding and other aesthetic problems. The aims of this study were to evaluate the relationship between some of mandibular anatomical landmarks and dental crowding in the patient with skeletal Cl II due to mandibular deficiency.   Materials and Methods: 108 cases have been randomly selected out of patients with mandibular relate...

  10. Bringing history to life: simulating landmark experiments in psychology.

    Boynton, David M; Smith, Laurence D

    2006-05-01

    The course in history of psychology can be challenging for students, many of whom enter it with little background in history and faced with unfamiliar names and concepts. The sheer volume of material can encourage passive memorization unless efforts are made to increase student involvement. As part of a trend toward experiential history, historians of science have begun to supplement their lectures with demonstrations of classic physics experiments as a way to bring the history of science to life. Here, the authors report on computer simulations of five landmark experiments from early experimental psychology in the areas of reaction time, span of attention, and apparent motion. The simulations are designed not only to permit hands-on replication of historically important results but also to reproduce the experimental procedures closely enough that students can gain a feel for the nature of early research and the psychological processes being studied. PMID:17152604

  11. Posterior belly of the digastric muscle: An important landmark for various head and neck surgeries

    Vrinda Hari Ankolekar

    2015-04-01

    Conclusion: As the PBD muscle is an important surgical landmark, the present study adds to the existing knowledge about it. The present study has also included few newer landmarks, which were not given importance in the previous studies. [Arch Clin Exp Surg 2015; 4(2.000: 79-82

  12. Reorienting strategies in a rectangular array of landmarks by domestic chicks (Gallus gallus).

    Pecchia, Tommaso; Vallortigara, Giorgio

    2010-05-01

    Spatial reorientation in a rectangular array of four landmarks located in the center of a circular enclosure was investigated in domestic chicks (Gallus gallus). One of the landmark possessed unique visual features, indicating the location of a food reward. After training, chicks were tested (a) with the same array as during the training; (b) with four identical landmarks of the type previously nonrewarded, of the type previously rewarded, or of a new type; (c) after having transformed one of the landmarks located at the geometric incorrect location into the type of landmark previously rewarded; or (d) with a fifth landmark of the rewarded type at a new location. Chicks encoded information provided by local featural cues but not the geometric information provided by the shape of the array. Moreover, when trained in a rectangular array of identical landmarks chicks failed to reorient. In a second series of experiments, the array was located in correspondence to the corners of a rectangular enclosure. This time chicks successfully learned to locate the reward using geometric information. However, when the rectangular array was located in the center of a larger rectangular enclosure, chicks failed to reorient, indicating that the geometric information given by the macroscopic layout of arena surfaces was not used to specify different locations. These results suggest that chicks reorient on the basis of a local representation of single landmarks and that encoding of the global aspects of geometry only occurs with respect to the large, extended surfaces of an enclosure. PMID:20476814

  13. An Evaluation of Cellular Neural Networks for the Automatic Identification of Cephalometric Landmarks on Digital Images

    Rosalia Leonardi

    2009-01-01

    Full Text Available Several efforts have been made to completely automate cephalometric analysis by automatic landmark search. However, accuracy obtained was worse than manual identification in every study. The analogue-to-digital conversion of X-ray has been claimed to be the main problem. Therefore the aim of this investigation was to evaluate the accuracy of the Cellular Neural Networks approach for automatic location of cephalometric landmarks on softcopy of direct digital cephalometric X-rays. Forty-one, direct-digital lateral cephalometric radiographs were obtained by a Siemens Orthophos DS Ceph and were used in this study and 10 landmarks (N, A Point, Ba, Po, Pt, B Point, Pg, PM, UIE, LIE were the object of automatic landmark identification. The mean errors and standard deviations from the best estimate of cephalometric points were calculated for each landmark. Differences in the mean errors of automatic and manual landmarking were compared with a 1-way analysis of variance. The analyses indicated that the differences were very small, and they were found at most within 0.59 mm. Furthermore, only few of these differences were statistically significant, but differences were so small to be in most instances clinically meaningless. Therefore the use of X-ray files with respect to scanned X-ray improved landmark accuracy of automatic detection. Investigations on softcopy of digital cephalometric X-rays, to search more landmarks in order to enable a complete automatic cephalometric analysis, are strongly encouraged.

  14. Looking beyond the Boundaries: Time to Put Landmarks Back on the Cognitive Map?

    Lew, Adina R.

    2011-01-01

    Since the proposal of Tolman (1948) that mammals form maplike representations of familiar environments, cognitive map theory has been at the core of debates on the fundamental mechanisms of animal learning and memory. Traditional formulations of cognitive map theory emphasize relations between landmarks and between landmarks and goal locations as…

  15. The Development of Landmark and Beacon Use in Young Children: Evidence from a Touchscreen Search Task

    Sutton, Jennifer E.

    2006-01-01

    Children ages 2, 3 and 4 years participated in a novel hide-and-seek search task presented on a touchscreen monitor. On beacon trials, the target hiding place could be located using a beacon cue, but on landmark trials, searching required the use of a nearby landmark cue. In Experiment 1, 2-year-olds performed less accurately than older children…

  16. Digital photography in anatomical pathology

    Leong F; Leong A

    2004-01-01

    Digital imaging has made major inroads into the routine practice of anatomical pathology and replaces photographic prints and Kodachromes for reporting and conference purposes. More advanced systems coupled to computers allow greater versatility and speed of turnaround as well as lower costs of incorporating macroscopic and microscopic pictures into pathology reports and publications. Digital images allow transmission to remote sites via the Internet for consultation, quality assurance and ed...

  17. Landmark and route knowledge in children’s spatial representation of a virtual environment

    Marion eNys

    2015-01-01

    Full Text Available This study investigates the development of landmark and route knowledge in complex wayfinding situations. Our study focuses on how children (aged 6, 8 and 10 years and young adults (n=79 indicate, recognize, and bind landmarks and directions in both verbal and visuo-spatial tasks after learning a virtual route. Performance in these tasks is also related to general verbal and visuo-spatial abilities as assessed by independent standardized tests (attention, working memory, perception of direction, production and comprehension of spatial terms, sentences and stories. The results first show that the quantity and quality of landmarks and directions produced and recognized by participants in both verbal and visuo-spatial tasks increased with age. In addition, an increase with age was observed in participants’ selection of decisional landmarks (i.e. landmarks associated with a change of direction, as well as in their capacity to bind landmarks and directions. Our results confirm the view that children first acquire landmark knowledge, then route knowledge, as shown by their late developing ability to bind knowledge of directions and landmarks. Overall, the quality of verbal and visuo-spatial information in participants’ spatial representations was found to vary mostly with their visuo-spatial abilities (attention and perception of directions and not with their verbal abilities. Interestingly, however, when asked to recognize landmarks encountered during the route, participants show an increasing bias with age toward choosing a related landmark of the same category, regardless of its visual characteristics, i.e. they incorrectly choose the picture of another fountain. The discussion highlights the need for further studies to determine more precisely the role of verbal and visuo-spatial knowledge and the nature of how children learn to represent and memorize routes.

  18. [Sigismund Laskowski and his anatomical preparations technique].

    Gryglewski, Ryszard W

    2015-01-01

    Fixation of the entire bodies or individual organs, and later as well tissues and cellular structures, was and still is often a challenge for anatomists and histologists. Technique that combines extensive knowledge of natural sciences, as well as technical skills, was by those best researchers as Frederik Ruysch, brought to perfection. Preparations, if done with care and talent, are really propelling progress in anatomical studies and determining the quality of education for medical students and young physicians. And as it is true for many of today's medical disciplines and natural sciences, the nineteenth century was in many ways a breaking point for preparatory techniques in the realm of anatomy and histology. Among those who have achieved success, earning notoriety during their lifetime and often going into the annals of European most distinguished scholars were some Polish names: Louis Maurice Hirschfeld, whose preparations of the nervous system earned him well-deserved, international fame, Louis Charles Teichmann, who was the very first so precisely describing the lymphatic system and a creator of unique injection mass, Henry Kadyi, known for his outstanding preparations, especially of vascular system. Henry Frederick Hoyer sen., who was one of the first to use formalin regularly for accurate microscopic preparations, is seen by many as the founder of the Polish histology. In this group of innovators and precursors of modern preparation techniques place should be reserved for Zygmunt (Sigismund) Laskowski, Polish patriot, fighting in January Uprising, later an immigrant, a professor at the university sequentially Paris and Geneva. Acclaimed author of anatomical tables and certainly creator of one of the groundbreaking techniques in anatomical preparations. Based after many years of research on the simple glycerine-phenol mixture achieved excellent results both in fixation of entire bodies and organs or tissues. Quality of those preparations was as high and

  19. Parametric Anatomical Modeling: A method for modeling the anatomical layout of neurons and their projections

    Martin ePyka

    2014-09-01

    Full Text Available Computational models of neural networks can be based on a variety of different parameters. These parameters include, for example, the 3d shape of neuron layers, the neurons' spatial projection patterns, spiking dynamics and neurotransmitter systems. While many well-developed approaches are available to model, for example, the spiking dynamics, there is a lack of approaches for modeling the anatomical layout of neurons and their projections. We present a new method, called Parametric Anatomical Modeling (PAM, to fill this gap. PAM can be used to derive network connectivities and conduction delays from anatomical data, such as the position and shape of the neuronal layers and the dendritic and axonal projection patterns. Within the PAM framework, several mapping techniques between layers can account for a large variety of connection properties between pre- and post-synaptic neuron layers. PAM is implemented as a Python tool and integrated in the 3d modeling software Blender. We demonstrate on a 3d model of the hippocampal formation how PAM can help reveal complex properties of the synaptic connectivity and conduction delays, properties that might be relevant to uncover the function of the hippocampus. Based on these analyses, two experimentally testable predictions arose: i the number of neurons and the spread of connections is heterogeneously distributed across the main anatomical axes, ii the distribution of connection lengths in CA3-CA1 differ qualitatively from those between DG-CA3 and CA3-CA3. Models created by PAM can also serve as an educational tool to visualize the 3d connectivity of brain regions. The low-dimensional, but yet biologically plausible, parameter space renders PAM suitable to analyse allometric and evolutionary factors in networks and to model the complexity of real networks with comparatively little effort.

  20. Quantification of organ motion based on an adaptive image-based scale invariant feature method

    Purpose: The availability of corresponding landmarks in IGRT image series allows quantifying the inter and intrafractional motion of internal organs. In this study, an approach for the automatic localization of anatomical landmarks is presented, with the aim of describing the nonrigid motion of anatomo-pathological structures in radiotherapy treatments according to local image contrast.Methods: An adaptive scale invariant feature transform (SIFT) was developed from the integration of a standard 3D SIFT approach with a local image-based contrast definition. The robustness and invariance of the proposed method to shape-preserving and deformable transforms were analyzed in a CT phantom study. The application of contrast transforms to the phantom images was also tested, in order to verify the variation of the local adaptive measure in relation to the modification of image contrast. The method was also applied to a lung 4D CT dataset, relying on manual feature identification by an expert user as ground truth. The 3D residual distance between matches obtained in adaptive-SIFT was then computed to verify the internal motion quantification with respect to the expert user. Extracted corresponding features in the lungs were used as regularization landmarks in a multistage deformable image registration (DIR) mapping the inhale vs exhale phase. The residual distances between the warped manual landmarks and their reference position in the inhale phase were evaluated, in order to provide a quantitative indication of the registration performed with the three different point sets.Results: The phantom study confirmed the method invariance and robustness properties to shape-preserving and deformable transforms, showing residual matching errors below the voxel dimension. The adapted SIFT algorithm on the 4D CT dataset provided automated and accurate motion detection of peak to peak breathing motion. The proposed method resulted in reduced residual errors with respect to standard SIFT

  1. TOPICAL REVIEW: Anatomical imaging for radiotherapy

    Evans, Philip M.

    2008-06-01

    scans is taken on different days. Both allow planning to account for variability intrinsic to the patient. Treatment verification has been carried out using a variety of technologies including: MV portal imaging, kV portal/fluoroscopy, MVCT, conebeam kVCT, ultrasound and optical surface imaging. The various methods have their pros and cons. The four x-ray methods involve an extra radiation dose to normal tissue. The portal methods may not generally be used to visualize soft tissue, consequently they are often used in conjunction with implanted fiducial markers. The two CT-based methods allow measurement of inter-fraction variation only. Ultrasound allows soft-tissue measurement with zero dose but requires skilled interpretation, and there is evidence of systematic differences between ultrasound and other data sources, perhaps due to the effects of the probe pressure. Optical imaging also involves zero dose but requires good correlation between the target and the external measurement and thus is often used in conjunction with an x-ray method. The use of anatomical imaging in radiotherapy allows treatment uncertainties to be determined. These include errors between the mean position at treatment and that at planning (the systematic error) and the day-to-day variation in treatment set-up (the random error). Positional variations may also be categorized in terms of inter- and intra-fraction errors. Various empirical treatment margin formulae and intervention approaches exist to determine the optimum strategies for treatment in the presence of these known errors. Other methods exist to try to minimize error margins drastically including the currently available breath-hold techniques and the tracking methods which are largely in development. This paper will review anatomical imaging techniques in radiotherapy and how they are used to boost the therapeutic benefit of the treatment.

  2. Germ band retraction as a landmark in glucose metabolism during Aedes aegypti embryogenesis

    Logullo Carlos

    2010-02-01

    Full Text Available Abstract Background The mosquito A. aegypti is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of A. aegypty life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during A. aegypti embryogenesis are unknown. Results Glucose metabolism was investigated throughout Aedes aegypti (Diptera embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE and germ band retraction (GBr, 24 HAE may be considered landmarks regarding glucose 6-phosphate (G6P destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP, of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK and pyruvate kinase (PK activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3 activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis. Conclusions The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose

  3. Landmark navigation and autonomous landing approach with obstacle detection for aircraft

    Fuerst, Simon; Werner, Stefan; Dickmanns, Dirk; Dickmanns, Ernst D.

    1997-06-01

    A machine perception system for aircraft and helicopters using multiple sensor data for state estimation is presented. By combining conventional aircraft sensor like gyros, accelerometers, artificial horizon, aerodynamic measuring devices and GPS with vision data taken by conventional CCD-cameras mounted on a pan and tilt platform, the position of the craft can be determined as well as the relative position to runways and natural landmarks. The vision data of natural landmarks are used to improve position estimates during autonomous missions. A built-in landmark management module decides which landmark should be focused on by the vision system, depending on the distance to the landmark and the aspect conditions. More complex landmarks like runways are modeled with different levels of detail that are activated dependent on range. A supervisor process compares vision data and GPS data to detect mistracking of the vision system e.g. due to poor visibility and tries to reinitialize the vision system or to set focus on another landmark available. During landing approach obstacles like trucks and airplanes can be detected on the runway. The system has been tested in real-time within a hardware-in-the-loop simulation. Simulated aircraft measurements corrupted by noise and other characteristic sensor errors have been fed into the machine perception system; the image processing module for relative state estimation was driven by computer generated imagery. Results from real-time simulation runs are given.

  4. Faithful Completion of Images of Scenic Landmarks Using Internet Images.

    Zhu, Zhe; Huang, Hao-Zhi; Tan, Zhi-Peng; Xu, Kun; Hu, Shi-Min

    2016-08-01

    Previous works on image completion typically aim to produce visually plausible results rather than factually correct ones. In this paper, we propose an approach to faithfully complete the missing regions of an image. We assume that the input image is taken at a well-known landmark, so similar images taken at the same location can be easily found on the Internet. We first download thousands of images from the Internet using a text label provided by the user. Next, we apply two-step filtering to reduce them to a small set of candidate images for use as source images for completion. For each candidate image, a co-matching algorithm is used to find correspondences of both points and lines between the candidate image and the input image. These are used to find an optimal warp relating the two images. A completion result is obtained by blending the warped candidate image into the missing region of the input image. The completion results are ranked according to combination score, which considers both warping and blending energy, and the highest ranked ones are shown to the user. Experiments and results demonstrate that our method can faithfully complete images. PMID:26394429

  5. Comparison of difference registration landmarks for image - guided radiotherapy for lung cancer%肺癌图像引导IMRT配准标志的比较研究

    张彦新; 惠周光; 李明辉; 章众; 符贵山; 戴建荣

    2015-01-01

    Objective To investigate the impact of anatomical landmarks on registration in image⁃guided radiotherapy (IGRT) for central and peripheral lung cancer. Methods Twenty⁃five patients with central or peripheral lung cancer for IGRT were enrolled in this study. Kilo⁃voltage cone⁃beam CT ( kV⁃CBCT) scanning was acquired before irradiotion. Tumor coverage on CBCT was assessed using gross tumor volume (GTV), clinical target volume (CTV), and planning target volume (PTV) contours according to tumor alignment, carina registration, and spine registration, respectively. The grading analysiswas based on visual tumor assessment as follows:grade 0, tumor within GTV;grade 1, tumor outside GTV but inside CTV;grade 2, tumor outside CTV but inside PTV;and grade 3, tumor outside PTV. Results Totally 177 sets of kV⁃CBCT of 25 patients was collected. According to the registration landmarks of the tumor, carina and spine for central lung cancer, the percentages were 57�55%, 53�77% and 16�04% in grade 0, 39�62%, 45�28%and 58�49% in grade 1, and 1�89%, 0�94% and 25�47% in grade 2, respectively. For peripheral lung cancer, the percentages were 47�89%, 14�08% and 2�82% in grade 0, 43�66%, 29�58% and 45�07% in grade 1, and 8�45%, 40�85% and 35�21% in grade 2, respectively. Conclusions For central lung cancer,the tumor was recommended as the best registration landmark, and the carina was recommended as well, while the spine was not recommended. For peripheral lung cancer, the tumor was recommended as the best registration landmark, while the spine and the carina were not recommended.%目的:研究肺癌患者图像引导IMRT中采用不同配准标志的靶区符合度差异,确定合理的图像配准方法。方法回顾性收集和分析25例肺癌患者CBCT影像,按原发肿瘤位置分为中央型和周围型两组,每组分别采用肿瘤、隆突、脊柱为标志的配准方法。根据肿瘤组织靶区符合度分为4

  6. Printed Three-dimensional Anatomic Templates for Virtual Preoperative Planning Before Reconstruction of Old Pelvic Injuries: Initial Results

    Xin-Bao Wu

    2015-01-01

    Full Text Available Background: Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy, difficult-to-access surgical sites, and the relatively low incidence of such cases. Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture. The goal of this study was to assess the use of three-dimensional (3D printing techniques for surgical management of old pelvic fractures. Methods: First, 16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data. Next, nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models. The pelvic injuries were all type C, and the average time from injury to reconstruction was 11 weeks (range: 8-17 weeks. The workflow consisted of: (1 Printing patient-specific bone models based on preoperative computed tomography (CT scans, (2 virtual fracture reduction using the printed 3D anatomic template, (3 virtual fracture fixation using Kirschner wires, and (4 preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation. These models aided communication between surgical team members during the procedure. This technique was validated by comparing the preoperative planning to the intraoperative procedure. Results: The accuracy of the 3D printed models was within specification. Production of a model from standard CT DICOM data took 7 hours (range: 6-9 hours. Preoperative planning using the 3D printed models was feasible in all cases. Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases. The patients were followed for 3-29 months (median: 5 months. The fracture healing time was 9-17 weeks (mean: 10 weeks. No delayed incision healing, wound infection, or nonunions occurred. The

  7. Printed Three-dimensional Anatomic Templates for Virtual Preoperative Planning Before Reconstruction of Old Pelvic Injuries: Initial Results

    Xin-Bao Wu; Jun-Qiang Wang; Chun-Peng Zhao; Xu Sun; Yin Shi; Zi-An Zhang; Yu-Neng Li

    2015-01-01

    Background:Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy,difficult-to-access surgical sites,and the relatively low incidence of such cases.Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture.The goal of this study was to assess the use of three-dimensional (3D) printing techniques for surgical management of old pelvic fractures.Methods:First,16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data.Next,nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models.The pelvic injuries were all type C,and the average time from injury to reconstruction was 11 weeks (range:8-17 weeks).The workflow consisted of.:(1) Printing patient-specific bone models based on preoperative computed tomography (CT) scans,(2) virtual fracture reduction using the printed 3D anatomic template,(3) virtual fracture fixation using Kirschner wires,and (4) preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation.These models aided communication between surgical team members during the procedure.This technique was validated by comparing the preoperative planning to the intraoperative procedure.Results:The accuracy of the 3D printed models was within specification.Production of a model from standard CT DICOM data took 7 hours (range:6-9 hours).Preoperative planning using the 3D printed models was feasible in all cases.Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases.The patients were followed for 3-29 months (median:5 months).The fracture healing time was 9-17 weeks (mean:l0 weeks).No delayed incision healing,wound infection,or nonunions occurred.The results were excellent in two cases,good in

  8. A global solution for the gravity field, rotation, landmarks and ephemeris of Eros

    Konopliv, A. S.; Miller, J. K.; Owen, W. M.; Yeomans, D. K.; Giorgini, J. D.; Garmier, R.; Barriot, J. P.

    2001-01-01

    This solution uses the entire one-year in orbit collection of X-band radiometric tracking (Doppler and range) from the Deep Space Network and landmark tracking observations generated from the NEAR spacecraft images of Eros.

  9. Anatomic consideration for preventive implantation.

    Denissen, H W; Kalk, W; Veldhuis, H A; van Waas, M A

    1993-01-01

    The aim of preventive implant therapy is to prevent or delay loss of alveolar ridge bone mass. For use in an anatomic study of 60 mandibles, resorption of the alveolar ridge was classified into four preventive stages: (1) after extraction of teeth; (2) after initial resorption; (3) when the ridge has atrophied to a knife-edge shape; and (4) when only basal bone remains. Implantation in stage 3 necessitates removal of the knife-edge ridge to create space for cylindrical implants. Therefore, implantation in stage 2 is advocated to prevent the development of stage 3. The aim of implantation in stage 4 is to prevent total loss of function of the atrophic mandible. PMID:8359876

  10. Internal Occipital Crest Misalignment with Internal Occipital Protuberance: A Case Report of Posterior Cranial Fossa Anatomic Variations

    Jae Ha Kim

    2016-01-01

    Full Text Available During gross anatomy head and neck laboratory session, one dissection group observed an abnormal anatomic variation in the posterior cranial fossa of a 94-year-old male cadaver. The internal occipital crest was not aligned with internal occipital protuberance and groove for superior sagittal sinus. It seemed that the internal occipital protuberance was shifted significantly to the right side. As a result the skull was overly stretched in order to connect with the internal occipital ridge. These internal skull variations of occipital bone landmarks can influence the location of adjacent dural venous sinuses and possibly influence cerebrospinal fluid flow. Similar anatomical anomalies have been attributed to presence of hydrocephalus and abnormalities in cisterna magna.

  11. Cálculo distribuido de landmarks para sistemas de planificación multiagente

    Oropesa Física, Ana

    2013-01-01

    En este Proyecto Final de Carrera se verá la motivación por la que hacer una heurística multiagente utilizando landmarks, la construcción de ésta y unos posteriores resultados y comparativas con la heurística monoagente entre otras. Oropesa Física, A. (2013). Cálculo distribuido de landmarks para sistemas de planificación multiagente. http://hdl.handle.net/10251/32520. Archivo delegado

  12. Effects of image enhancement on reliability of landmark identification in digital cephalometry

    M Oshagh

    2013-01-01

    Full Text Available Introduction: Although digital cephalometric radiography is gaining popularity in orthodontic practice, the most important source of error in its tracing is uncertainty in landmark identification. Therefore, efforts to improve accuracy in landmark identification were directed primarily toward the improvement in image quality. One of the more useful techniques of this process involves digital image enhancement which can increase overall visual quality of image, but this does not necessarily mean a better identification of landmarks. The purpose of this study was to evaluate the effectiveness of digital image enhancements on reliability of landmark identification. Materials and Methods: Fifteen common landmarks including 10 skeletal and 5 soft tissues were selected on the cephalograms of 20 randomly selected patients, prepared in Natural Head Position (NHP. Two observers (orthodontists identified landmarks on the 20 original photostimulable phosphor (PSP digital cephalogram images and 20 enhanced digital images twice with an intervening time interval of at least 4 weeks. The x and y coordinates were further analyzed to evaluate the pattern of recording differences in horizontal and vertical directions. Reliability of landmarks identification was analyzed by paired t test. Results: There was a significant difference between original and enhanced digital images in terms of reliability of points Ar and N in vertical and horizontal dimensions, and enhanced images were significantly more reliable than original images. Identification of A point, Pogonion and Pronasal points, in vertical dimension of enhanced images was significantly more reliable than original ones. Reliability of Menton point identification in horizontal dimension was significantly more in enhanced images than original ones. Conclusion: Direct digital image enhancement by altering brightness and contrast can increase reliability of some landmark identification and this may lead to more

  13. Optimizing conditions for computer-assisted anatomical learning

    Luursema, Jan-Maarten; Verwey, Willem B.; Kommers, Piet A.M.; Geelkerken, Robert H.; Vos, Hans J.

    2006-01-01

    An experiment evaluated the impact of two typical features of virtual learning environments on anatomical learning for users of differing visuo-spatial ability. The two features studied are computer-implemented stereopsis (the spatial information that is based on differences in visual patterns proje

  14. Dosimetric accuracy of a deterministic radiation transport based 192Ir brachytherapy treatment planning system. Part III. Comparison to Monte Carlo simulation in voxelized anatomical computational models

    Purpose: To compare TG43-based and Acuros deterministic radiation transport-based calculations of the BrachyVision treatment planning system (TPS) with corresponding Monte Carlo (MC) simulation results in heterogeneous patient geometries, in order to validate Acuros and quantify the accuracy improvement it marks relative to TG43. Methods: Dosimetric comparisons in the form of isodose lines, percentage dose difference maps, and dose volume histogram results were performed for two voxelized mathematical models resembling an esophageal and a breast brachytherapy patient, as well as an actual breast brachytherapy patient model. The mathematical models were converted to digital imaging and communications in medicine (DICOM) image series for input to the TPS. The MCNP5 v.1.40 general-purpose simulation code input files for each model were prepared using information derived from the corresponding DICOM RT exports from the TPS. Results: Comparisons of MC and TG43 results in all models showed significant differences, as reported previously in the literature and expected from the inability of the TG43 based algorithm to account for heterogeneities and model specific scatter conditions. A close agreement was observed between MC and Acuros results in all models except for a limited number of points that lay in the penumbra of perfectly shaped structures in the esophageal model, or at distances very close to the catheters in all models. Conclusions: Acuros marks a significant dosimetry improvement relative to TG43. The assessment of the clinical significance of this accuracy improvement requires further work. Mathematical patient equivalent models and models prepared from actual patient CT series are useful complementary tools in the methodology outlined in this series of works for the benchmarking of any advanced dose calculation algorithm beyond TG43.

  15. Insite: Canada's landmark safe injecting program at risk

    Drucker Ernest

    2006-08-01

    Full Text Available Abstract InSite is North Americas first supervised injection site and a landmark public heath initiative operating in Vancouver since 2003. The program is a vital component of that cities internationally recognized harm reduction approach to its serious problems with drugs, crime, homelessness and AIDS. InSite currently operates under a waiver of Federal rules that allow it to provide services as a research project. An extensive evaluation has produced very positive results for thousands of users. Normally such strong evidence documenting the successes of such a program, and the medical and public health significance of these positive outcomes, would be the basis for celebration and moves to expand the model and provide similar services elsewhere in Canada. Instead, there is a distinct possibility that InSite will be closed by the newly elected Canadian Prime Minister Paul Harper – a conservative who has traveled to the US to visit George WQ Bush and come back antagonistic to harm reduction in all its forms. Because InSites federal waiver is expiring and up for renewal in September, the fear is that Mr. Harpers will not renew the approval and that the program will be forced to close down. The risks associated with the potential closure of InSite need to be fully understood. This editorial lays out these public health risks and the associated economic impact if InSite were to be closed. In addition to preventable deaths and disease, InSites closure will cost Vancouver and British Columbia between $3.8 and $ 8.8 million in preventable health care expenses over the next two years.

  16. Ultrasound Guided Internal Jugular Venous Cannulation: Comparison with Land-Mark Technique

    Objective: To compare real-time ultrasonography-guided technique versus the traditional land-mark technique for internal Jugular venous cannulation. Study Design: Randomized controlled trial. Place and Duration of Study: Department of Anaesthesia, Combined Military Hospital, Rawalpindi, from September 2013 to July 2014. Methodology:Atotal of 200 patients who required internal jugular vein cannulation were randomly assigned using either real-time ultrasound-guided technique or land-mark technique. Access time, number of attempts until successful cannulation, complications and the demographics of each patient were recorded. Results:Access time was significantly less in real-time ultrasound group (34.95 ± 11.47 vs. 146.59 ± 40.20 seconds, p < 0.001). Cannulation was performed in first attempt in 99 percentage of patients in ultrasound group as compared to 89 percentage of landmark group. Complication rate was significantly higher in the land-mark group than in the ultrasound-guided group. Carotid artery puncture rate (9 percentage vs. 1 percentage) and haematoma formation (7 percentage vs. 0 percentage) were more frequent in the land-mark group than in the ultrasound-guided group. Brachial plexus irritation was also more in land-mark group (6 percentage vs. 0 percentage). Conclusion:Access time, failure rate and procedure related complications are reduced when real-time ultrasonography is used to cannulate internal Jugular vein. (author)

  17. Anatomical and morphological adaptation of the leaves of Eragrostis minor Host (Poaceae in different ecological conditions

    Nataliia A. Pashkevych

    2014-04-01

    Full Text Available A study of the variability of the anatomical features of the leaf of Eragrostis minor Host from model cenopopulations, different by their affinity coenotic, environmental features and the degree of influence of the recreation has been carried out. The significant correlation between leaf characteristics was established, and estimated similarity of cenopopulations was analyzed on the base of leaf anatomical features.

  18. Anatomical and morphological adaptation of the leaves of Eragrostis minor Host (Poaceae) in different ecological conditions

    Nataliia A. Pashkevych

    2014-01-01

    A study of the variability of the anatomical features of the leaf of Eragrostis minor Host from model cenopopulations, different by their affinity coenotic, environmental features and the degree of influence of the recreation has been carried out. The significant correlation between leaf characteristics was established, and estimated similarity of cenopopulations was analyzed on the base of leaf anatomical features.

  19. Evaluation of contrast reproduction method based on the anatomical guidance of the cerebral images reconstruction in positron emission tomography; Evaluation d'une methode de restitution de contraste basee sur le guidage anatomique de la reconstruction des images cerebrales en tomographie par emission de positons

    Bataille, F

    2007-04-15

    Positron emission tomography is a medical imaging modality providing in-vivo volumetric images of functional processes of the human body, which is used for the diagnosis and the following of neuro degenerative diseases. PET efficiency is however limited by its poor spatial resolution, which generates a decrease of the image local contrast and leads to an under-estimation of small cerebral structures involved in the degenerative mechanism of those diseases. This so-called partial volume effect degradation is usually corrected in a post-reconstruction processing framework through the use of anatomical information, whose spatial resolution allows a better discrimination between functional tissues. However, this kind of method has the major drawback of being very sensitive to the residual mismatches on the anatomical information processing. We developed in this thesis an alternative methodology to compensate for the degradation, by incorporating in the reconstruction process both a model of the system impulse response and an anatomically-based image prior constraint. This methodology was validated by comparison with a post-reconstruction correction strategy, using data from an anthropomorphic phantom acquisition and then we evaluated its robustness to the residual mismatches through a realistic Monte Carlo simulation corresponding to a cerebral exam. The proposed algorithm was finally applied to clinical data reconstruction. (author)

  20. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  1. Digital inlaid design based on anatomical characteristics and preliminary implementation of its program%基于解剖特征的数字化嵌体设计及程序的初步实现

    宋杨; 孙玉春; 王勇; 韩景芸; 吕培军

    2011-01-01

    Objective : To explore the technical guideline of inlays computer aided design ( CAD) for further development, to test the feasibility of processing for the design results of the technical guideline, and to assist co-operation with automatic inlay CAD software development. Methods: On the basis of point cloud data of right mandibular first molar of standard crown, we established the coordinate system, the landmarks and lines and the characteristic curves. A dental cast of right mandibular first molar MODinlay of an individual normal occlusion was scanned. The following objects were digitized: prepared tooth、neighbor teeth and intercuspal bite record. On the basis of parametric standard crown established in the research, using Surfacer 11. 0, we achieved the reconstruction of MOD-inlay by extracting margin line, constructing tissue surface, constructing outer surface and occlusal grinding, then the design result was processed and try-in on the cast. We also developed automatic inlay CAD software based on the guideline of inlay CAD. Results : The guideline of inlay CAD was established, the design results were processed and an automatic inlay CAD software was developed on basis of Surfacer 11. 0. Conclusion: It is a feasible method to establish technical guideline of inlay based on reverse engineering technology and process its design result, and a automatic inlay CAD software could be developed based on the technical guideline.%目的:应用逆向工程软件,探索一条开发嵌体CAD软件的技术路线,验证其加工可行性,并尝试应用二次开发软件平台进行具有较高自动化设计能力的嵌体CAD软件程序的研发.方挂:首先在标准冠点云数据上创建坐标系、标志点/线以及特征曲线,建立参数化标准冠数据集,然后使用线激光扫描仪进行嵌体预备体、邻牙及咬合记录的数据采集并进行三维数据建模,再应用Surfacer 11.0软件,基于建立的参数化标准冠数据集,通过提取

  2. An anatomical and functional topography of human auditory cortical areas

    Michelle eMoerel

    2014-07-01

    Full Text Available While advances in magnetic resonance imaging (MRI throughout the last decades have enabled the detailed anatomical and functional inspection of the human brain non-invasively, to date there is no consensus regarding the precise subdivision and topography of the areas forming the human auditory cortex. Here, we propose a topography of the human auditory areas based on insights on the anatomical and functional properties of human auditory areas as revealed by studies of cyto- and myelo-architecture and fMRI investigations at ultra-high magnetic field (7 Tesla. Importantly, we illustrate that - whereas a group-based approach to analyze functional (tonotopic maps is appropriate to highlight the main tonotopic axis - the examination of tonotopic maps at single subject level is required to detail the topography of primary and non-primary areas that may be more variable across subjects. Furthermore, we show that considering multiple maps indicative of anatomical (i.e. myelination as well as of functional properties (e.g. broadness of frequency tuning is helpful in identifying auditory cortical areas in individual human brains. We propose and discuss a topography of areas that is consistent with old and recent anatomical post mortem characterizations of the human auditory cortex and that may serve as a working model for neuroscience studies of auditory functions.

  3. Multiple landmarks, the encoding of environmental geometry and the spatial logics of a dual brain.

    Chiesa, A Della; Pecchia, T; Tommasi, L; Vallortigara, G

    2006-10-01

    A series of place learning experiments was carried out in young chicks (Gallus gallus) in order to investigate how the geometry of a landmark array and that of a walled enclosure compete when disoriented animals could rely on both of them to re-orient towards the centre of the enclosure. A square-shaped array (four wooden sticks) was placed in the middle of a square-shaped enclosure, the two structures being concentric. Chicks were trained to ground-scratch to search for food hidden in the centre of the enclosure (and the array). To check for effects of array degradation, one, two, three or all landmarks were removed during test trials. Chicks concentrated their searching activity in the central area of the enclosure, but their accuracy was inversely contingent on the number of landmarks removed; moreover, the landmarks still present within the enclosure appeared to influence the shape of the searching patterns. The reduction in the number of landmarks affected the searching strategy of chicks, suggesting that they had focussed mainly on local cues when landmarks were present within the enclosure. When all the landmarks were removed, chicks searched over a larger area, suggesting an absolute encoding of distances from the local cues and less reliance on the relationships provided by the geometry of the enclosure. Under conditions of monocular vision, chicks tended to rely on different strategies to localize the centre on the basis of the eye (and thus the hemisphere) in use, the left hemisphere attending to details of the environment and the right hemisphere attending to the global shape. PMID:16941155

  4. Three-dimensional modeling of human hands based on hand anatomical structures%基于解剖结构可视化手模型的构建

    白桂有; 张正治; 杨博贵; 孙华; 贾卫斗

    2007-01-01

    确显示手掌部主要解剖结构.%BACKGROUND:The anatomic structures and kinetic characteristics are the bases to establish hand model, and the kinetic characteristics of hand are determined by the anatomic structure. So, numerous scholars have paid close attention to virtual hand models based on the anatomic structures of hand.OBJECTIVE: To construct visible hand model based on anatomic structure.DESIGN: Single sample trial.SETTING: Center Laboratory, Third Military Medical University of Chinese PLA.MATERIALS: This trial was carried out in the Center Laboratory, Third Military Medical University of Chinese PLA in October 2003. Two fresh adult hands, which involved wrist joint, provided by the Department of Anatomy, Third Military Medical University of Chinese PLA, were employed. The two hands had no organic damage by naked observation.METHODS: The specimens were embedded and mill-cut (mill-cut layer thinness 0.2 mm). Cannon (ESO 1OD) digital camera (6.3 million pixel) was used for image collection. Each image was 31.5 MB, Data of 1 200 images were obtained.Adobe Photoshop 7.0 software was used for image treatment and then two-dimensional cross-section images were collected. The bone, flexor tendon and the outline of hand was three-dimensionally reconstructed by using the software,which was developed by the Department of Computer Science and Technology,Tsinghua University and Institute of Computer Medicine, Department of Anatomy, Third Military Medical University of Chinese PLA.MATN OUTCOME MEASURES: Three-dimensional reconstruction of the bone, flexor tendon and outline of hand.RESULTS: ①The outline of hand: After being reconstructed, the outline, which consisted of all fingers and nails, was well displayed, and observed from many directions.② Three-dimensional reconstruction of the bone of hand: The reconstructed bones of hands involved digital bones, metacarpal bones, carpal bones and all joints, and they could be displayed solely or in groups with other

  5. Anatomic registration based on medial axis parametrizations

    Vera Hernàndez, Sergio; González Ballester, Miguel Ángel,

    2015-01-01

    El corregistro de imagines ha sido durante muchos años el método estándar para poner dos imágenes en correspondencia. Se ha usado de manera generalizada en el campo de la imagen médica, para poner imágenes de dos pacientes diferentes en una misma posición de solapamiento en el espacio. Sin embargo, el corregistro de estas imágenes es un proceso iterativo y lento de muchas variables y con tendencia a caer en mínimos de energía local. Un sistema de coordenadas que parametrizase el interior de l...

  6. Anatomic registration based on medial axis parametrizations

    Vera Hernàndez, Sergio

    2015-01-01

    El corregistro de imagines ha sido durante muchos años el método estándar para poner dos imágenes en correspondencia. Se ha usado de manera generalizada en el campo de la imagen médica, para poner imágenes de dos pacientes diferentes en una misma posición de solapamiento en el espacio. Sin embargo, el corregistro de estas imágenes es un proceso iterativo y lento de muchas variables y con tendencia a caer en mínimos de energía local. Un sistema de coordenadas que parametrizase el interior d...

  7. A hierarchical scheme for geodesic anatomical labeling of airway trees

    Feragen, Aasa; Petersen, Jens; Owen, Megan; Lo, Pechin Chien Pau; Thomsen, Laura; Wille, Mathilde; Dirksen, Asger; de Bruijne, Marleen

    We present a fast and robust supervised algorithm for label- ing anatomical airway trees, based on geodesic distances in a geometric tree-space. Possible branch label configurations for a given unlabeled air- way tree are evaluated based on the distances to a training set of labeled airway trees....... Disease (COPD). Performance is statis- tically similar to the inter- and intra-expert agreement, and we found no significant correlation between COPD stage and labeling accuracy....

  8. An anatomic gene expression atlas of the adult mouse brain

    Ng, Lydia; Bernard, Amy; Lau, Chris; Overly, Caroline C.; Dong, Hong-Wei; Kuan, Chihchau; Pathak, Sayan; Sunkin, Susan M.; Dang, Chinh; Bohland, Jason W.; Bokil, Hemant; Mitra, Partha P.; Puelles, Luis; Hohmann, John; Anderson, David J.

    2009-01-01

    Studying gene expression provides a powerful means of understanding structure-function relationships in the nervous system. The availability of genome-scale in situ hybridization datasets enables new possibilities for understanding brain organization based on gene expression patterns. The Anatomic Gene Expression Atlas (AGEA) is a new relational atlas revealing the genetic architecture of the adult C57Bl/6J mouse brain based on spatial correlations across expression data for thousands of gene...

  9. Pattern recognition of anatomical shapes in CT scans

    In medical image processing pattern recognition has become of major value in anatomical analysis and in computer aided information processing. Specifically, pattern recognition techniques simplify software development by means of which clinicians can manipulate anatomical relationships. As part of an overall CT pattern recognition system, a sequential edge tracking routine was devised together with a normalized Fourier descriptor analysis of identified shapes. A collection of shapes were extracted from CT scans of two patients and entered into an anatomic shape dictionary. This dictionary was employed in pattern matching experiments and in three-dimensional anatomical reconstruction. A sequential-edge tracking algorithm of high reliability, consistency, and image invariance, capable of utilizing heuristic and statistical rules, was demonstrated. Tests of pattern matching algorithms based on Fourier descriptors provided rapid and accurate body organ recognition of shapes extracted from de novo images using the shape dictionary. Results indicate that automated contour extraction and object recognition from cross-sectional images of human anatomy can be performed effectively, reliably, and rapidly. This abstract discusses an image processing environment that circumvents manual and subjective shape extraction, by substituting automatic and quantitative shape extraction, pattern matching and object recognition

  10. Multiple variations of the tendons of the anatomical snuffbox

    Thwin, San San; Zaini, Fazlin; Than, Myo

    2014-01-01

    INTRODUCTION Multiple tendons of the abductor pollicis longus (APL) in the anatomical snuffbox of the wrist can lead to the development of de Quervain's syndrome, which is caused by stenosing tenosynovitis. A cadaveric study was performed to establish the variations present in the tendons of the anatomical snuffbox in a Malaysian population, in the hope that this knowledge would aid clinical investigation and surgical treatment of de Quervain's tenosynovitis. METHODS Routine dissection of ten upper limbs was performed to determine the variations in the tendons of the anatomical snuffbox of the wrist. RESULTS In all the dissected upper limbs, the APL tendon of the first extensor compartment was found to have several (3–14) tendon slips. The insertion of the APL tendon slips in all upper limbs were at the base of the first metacarpal bone, trapezium and fascia of the opponens pollicis muscle; however, in seven specimens, they were also found to be attached to the fleshy belly of the abductor pollicis brevis muscle. In two specimens, double tendons of the extensor pollicis longus located in the third extensor compartment were inserted into the capsule of the proximal interphalangeal joints before being joined to the extensor expansion. In two other specimens, the first extensor compartment had two osseofibrous tunnels divided by a septum that separated the APL tendon from the extensor pollicis brevis tendon. CONCLUSION Multiple variations were found in the anatomical snuffbox region of the dissected upper limbs. Knowledge of these variations would be useful in interventional radiology and orthopaedic surgery. PMID:24452976

  11. Altered anatomical network in early blindness revealed by diffusion tensor tractography.

    Ni Shu

    Full Text Available The topological architecture of the cerebral anatomical network reflects the structural organization of the human brain. Recently, topological measures based on graph theory have provided new approaches for quantifying large-scale anatomical networks. Diffusion MRI studies have revealed the efficient small-world properties and modular structure of the anatomical network in normal subjects. However, no previous study has used diffusion MRI to reveal changes in the brain anatomical network in early blindness. Here, we utilized diffusion tensor imaging to construct binary anatomical networks for 17 early blind subjects and 17 age- and gender-matched sighted controls. We established the existence of structural connections between any pair of the 90 cortical and sub-cortical regions using deterministic tractography. Compared with controls, early blind subjects showed a decreased degree of connectivity, a reduced global efficiency, and an increased characteristic path length in their brain anatomical network, especially in the visual cortex. Moreover, we revealed some regions with motor or somatosensory function have increased connections with other brain regions in the early blind, which suggested experience-dependent compensatory plasticity. This study is the first to show alterations in the topological properties of the anatomical network in early blindness. From the results, we suggest that analyzing the brain's anatomical network obtained using diffusion MRI data provides new insights into the understanding of the brain's re-organization in the specific population with early visual deprivation.

  12. Ultrasound Anatomical Visualization of the rabbit liver

    Kamelia Dimcheva Stamatova-Yovcheva; Rosen Dimitrov; David Yovchev; Krassimira Uzunova; Rumen Binev

    2014-01-01

    The topic was to investigate the anatomical features of the rabbit liver by two- and three-dimensional ultrasonography. Eighteen sexually mature healthy clinically New Zealand rabbits aged eight months were studied. Two-dimensional ultarsonographic anatomical image of the rabbit liver presented it in the cranial abdominal region as a relatively hypoechoic finding. Its contours were regular and in close contact with the hyperechoic diaphragm. Liver parenchyma was heterogeneous. The gall bladde...

  13. Do familiar landmarks reset the global path integration system of desert ants?

    Collett, M; Collett, T S; Chameron, S; Wehner, R

    2003-03-01

    It is often suggested that animals may link landmark memories to a global coordinate system provided by path integration, thereby obtaining a map-like representation of familiar terrain. In an attempt to discover if desert ants form such associations we have performed experiments that test whether desert ants recall a long-term memory of a global path integration vector on arriving at a familiar food site. Ants from three nests were trained along L-shaped routes to a feeder. Each route was entirely within open-topped channels that obscured all natural landmarks. Conspicuous artificial landmarks were attached to the channelling that formed the latter part of the route. The homeward vectors of ants accustomed to the route were tested with the foodward route, either as in training, or with the first leg of the L shortened or extended. These ants were taken from the feeder to a test area and released, whereupon they performed a home vector. If travelling the latter part of a familiar route and arriving at a familiar food site triggers the recall of an accustomed home vector, then the home vector should be the same under both test conditions. We find instead that the home vector tended to reflect the immediately preceding outward journey. In conjunction with earlier work, these experiments led us to conclude in the case of desert ants that landmark memories do not prime the recall of long-term global path integration memories. On the other hand, landmark memories are known to be linked to local path integration vectors that guide ants along a segment of a route. Landmarks thus seem to provide procedural information telling ants what action to perform next but not the positional information that gives an ant its location relative to its nest. PMID:12547942

  14. Surgeon's view of the skull base from the lateral approach.

    Goldenberg, R A

    1984-12-01

    This paper presents the surgical anatomy of the skull base and infratemporal fossa. The information has been derived from the author's own experience in surgical and cadaver dissection, standard anatomical references, and selected experience of other skull base surgeons. Because the lateral approach has become the utilitarian method of exposure, the intricate detailed anatomy is demonstrated from this view at five levels of dissection, so the surgeon may gain a practical understanding of the surgical relationship of critical structures. Consistent anatomical landmarks can be used by the surgeon in the location of these critical structures. The styloid process, sphenoidal spine, and middle meningeal artery identify the internal carotid artery as it enters the carotid canal. The bony or fibrous septum that divides the jugular foramen into neural and vascular compartments may be used to better identify nerves IX, X, and XI. The zygomatic root is useful for location of the middle fossa dura. The lateral pterygoid plate leads directly to the foramen ovale. The increased precision of dissection permitted by use of the microscope requires an increased level of knowledge of anatomical structures in this area. It is hoped that the information presented in this paper will assist surgeons in the meticulous and thorough removal of skull base tumors and in the preservation of neural and vascular structures that are presently being sacrificed. PMID:6503585

  15. Atlas Toolkit: Fast registration of 3D morphological datasets in the absence of landmarks.

    Grocott, Timothy; Thomas, Paul; Münsterberg, Andrea E

    2016-01-01

    Image registration is a gateway technology for Developmental Systems Biology, enabling computational analysis of related datasets within a shared coordinate system. Many registration tools rely on landmarks to ensure that datasets are correctly aligned; yet suitable landmarks are not present in many datasets. Atlas Toolkit is a Fiji/ImageJ plugin collection offering elastic group-wise registration of 3D morphological datasets, guided by segmentation of the interesting morphology. We demonstrate the method by combinatorial mapping of cell signalling events in the developing eyes of chick embryos, and use the integrated datasets to predictively enumerate Gene Regulatory Network states. PMID:26864723

  16. A Catalytic Role for Mod5 in the Formation of the Tea1 Cell Polarity Landmark

    Bicho, Claudia C.; Kelly, David A.; Snaith, Hilary A.; Goryachev, Andrew B.; Sawin, Kenneth E.

    2010-01-01

    Summary Many systems regulating cell polarity involve stable landmarks defined by internal cues [1–5]. In the rod-shaped fission yeast Schizosaccharomyces pombe, microtubules regulate polarized vegetative growth via a landmark involving the protein Tea1 [6–9]. Tea1 is delivered to cell tips as packets of molecules associated with growing microtubule ends [10] and anchored at the plasma membrane via a mechanism involving interaction with the membrane protein Mod5 [11, 12]. Tea1 and Mod5 are hi...

  17. Analysis of anatomic variability in children with low mathematical skills

    Han, Zhaoying; Fuchs, Lynn; Davis, Nikki; Cannistraci, Christopher J.; Anderson, Adam W.; Gore, John C.; Dawant, Benoit M.

    2008-03-01

    Mathematical difficulty affects approximately 5-9% of the population. Studies on individuals with dyscalculia, a neurologically based math disorder, provide important insight into the neural correlates of mathematical ability. For example, cognitive theories, neuropsychological studies, and functional neuroimaging studies in individuals with dyscalculia suggest that the bilateral parietal lobes and intraparietal sulcus are central to mathematical performance. The purpose of the present study was to investigate morphological differences in a group of third grade children with poor math skills. We compare population averages of children with low math skill (MD) to gender and age matched controls with average math ability. Anatomical data were gathered with high resolution MRI and four different population averaging methods were used to study the effect of the normalization technique on the results. Statistical results based on the deformation fields between the two groups show anatomical differences in the bilateral parietal lobes, right frontal lobe, and left occipital/parietal lobe.

  18. Generalized metrics induced anatomical prior for MAP PET image reconstruction

    Information theoretic metrics, including mutual information (MI) and joint entropy (JE), have been investigated as priors to incorporate anatomical information in ill-posed positron emission tomography (PET) image reconstruction. These metrics are generally based on the Shannon entropy. Meanwhile, in this paper, we proposed a generalized metrics induced anatomical prior for maximum a posteriori (MAP) PET reconstruction based on the generalized Shannon entropy metrics or Tsallis entropy. For the presented prior computation, a non-parametric method was used to estimate the joint probability density of the PET and MR image. Furthermore, we also developed an one-step-advance (OSA) MAP algorithm for PET image reconstruction with the presented prior regularization. Simulation results show that the presented novel prior has significantly improved the reconstructed PET image quality. (orig.)

  19. Three-dimensional study of pelvic asymmetry on anatomical specimens and its clinical perspectives.

    Boulay, Christophe; Tardieu, Christine; Bénaim, Charles; Hecquet, Jérome; Marty, Catherine; Prat-Pradal, Dominique; Legaye, Jean; Duval-Beaupère, Ginette; Pélissier, Jacques

    2006-01-01

    The aim of this study was to assess pelvic asymmetry (i.e. to determine whether the right iliac bone and the right part of the sacrum are mirror images of the left), both quantitatively and qualitatively, using three-dimensional measurements. Pelvic symmetry was described osteologically using a common reference coordinate system for a large sample of pelvises. Landmarks were established on 12 anatomical specimens with an electromagnetic Fastrak system. Seventy-one paired variables were tested with a paired t-test and a non-parametric test (Wilcoxon). A Pearson correlation matrix between the right and left values of the same variable was applied exclusively to values that were significantly asymmetric in order to calculate a dimensionless asymmetry index, ABGi, for each variable. Fifteen variables were significantly asymmetric and correlated with the right vs. left sides for the following anatomical regions: sacrum, iliac blades, iliac width, acetabulum and the superior lunate surface of the acetabulum. ABGi values above a threshold of +/- 4.8% were considered significantly asymmetric in seven variables of the pelvic area. Total asymmetry involving the right and the left pelvis seems to follow a spiral path in the pelvis; in the upper part, the iliac blades rotate clockwise, and in the lower part, the pubic symphysis rotates anticlockwise. Thus, pelvic asymmetry may be evaluated in clinical examinations by measuring iliac crest orientation. PMID:16420376

  20. Three-dimensional study of pelvic asymmetry on anatomical specimens and its clinical perspectives

    Boulay, Christophe; Tardieu, Christine; Bénaim, Charles; Hecquet, Jérome; Marty, Catherine; Prat-Pradal, Dominique; Legaye, Jean; Duval-Beaupère, Ginette; Pélissier, Jacques

    2006-01-01

    The aim of this study was to assess pelvic asymmetry (i.e. to determine whether the right iliac bone and the right part of the sacrum are mirror images of the left), both quantitatively and qualitatively, using three-dimensional measurements. Pelvic symmetry was described osteologically using a common reference coordinate system for a large sample of pelvises. Landmarks were established on 12 anatomical specimens with an electromagnetic Fastrak system. Seventy-one paired variables were tested with a paired t-test and a non-parametric test (Wilcoxon). A Pearson correlation matrix between the right and left values of the same variable was applied exclusively to values that were significantly asymmetric in order to calculate a dimensionless asymmetry index, ABGi, for each variable. Fifteen variables were significantly asymmetric and correlated with the right vs. left sides for the following anatomical regions: sacrum, iliac blades, iliac width, acetabulum and the superior lunate surface of the acetabulum. ABGi values above a threshold of ± 4.8% were considered significantly asymmetric in seven variables of the pelvic area. Total asymmetry involving the right and the left pelvis seems to follow a spiral path in the pelvis; in the upper part, the iliac blades rotate clockwise, and in the lower part, the pubic symphysis rotates anticlockwise. Thus, pelvic asymmetry may be evaluated in clinical examinations by measuring iliac crest orientation. PMID:16420376

  1. Anatomical Localization of Lister’s Tubercle and its Clinical and Surgical Importance

    Ağır, İsmail; Aytekin, Mahmut Nedim; Küçükdurmaz, Fatih; Gökhan, Servan; Çavuş, Umut Yücel

    2014-01-01

    The dorsal tubercle of the radius, once called Lister’s tubercle, is used as a landmark in wrist arthroscopy, wrist joint injections, and similar surgical and clinical procedures. However, there is no useful information in the reference anatomy books and literature. The aim of this study was to identify the anatomical localization of Lister’s tubercle on the dorsum of radius in relation to the radial styloid process and the ulnar notch of radius and to demonstrate the clinical and surgical importance of these relationships. We studied 20 dried cadaver radius specimens. The distances from Lister’s tubercle to the radial styloid process and to the ulnar notch were measured by using a digital micrometer caliber and the ratio of the two measures was calculated. The dorsal tubercle of the radius is variable in position and can be either closer to the radial styloid process or to the ulnar notch. The present study showed that in 11 of the radii the dorsal tubercle of the radius was nearer to the radial styloid process than the ulnar notch, while in 9 subjects it was nearer to the ulnar notch. This anatomical variation may be relevant for wrist injections, wrist artroscopy or wrist surgery. PMID:24843388

  2. MORPHOLOGICAL ANATOMICAL AND PHITOCHEMICAL CHARACTERISTICS OF SOME ALGAE

    N. S. Kaysheva; M. N. Arkhipova; A. S. Kayshev

    2014-01-01

    Morphological and anatomical features of thalluses of brown (Laminaria saccharina, Fucus vesiculosus) and red (Ahnfeltia plicata) algae, procured at a coastal strip of the Northern basin in gulfs of Ura-Guba and Palkina-Guba at different depths. Compliance of Fucus and Ahnfeltia with pharmacopoeial norms and merchandising indices for Laminaria was established, except for high concentration of sand in Ahnfeltia thalluses. The identity of algae between each other was shown based on the results ...

  3. The aspects regarding Chrysanthemum vitro- and exvitroplantlets anatomical structure

    Adriana PETRUS-VANCEA

    2007-05-01

    Full Text Available This study was consecrate to observe the histoanatomical structure of roots stems and leafs of Chrysanthemum vitroplantlets, in their vitroculture period and of exvitroplantlets, at 30 days from their septic medium transfer. The registered observations were compared with those realized at similar organs level of greenhouse plants (control lot. The noted differences between vitroplantlets anatomical structure and that greenhouse plants had, in special, ontogenetic bases.

  4. Testing anatomically specified hypotheses in functional imaging using cytoarchitectonic maps.

    Eickhoff, Simon B; Heim, Stefan; Zilles, Karl; Amunts, Katrin

    2006-08-15

    The statistical inference on functional imaging data is severely complicated by the embedded multiple testing problem. Defining a region of interest (ROI) where the activation is hypothesized a priori helps to circumvent this problem, since in this case the inference is restricted to fewer simultaneous tests, rendering it more sensitive. Cytoarchitectonic maps obtained from postmortem brains provide objective, a priori ROIs that can be used to test anatomically specified hypotheses about the localization of functional activations. We here analyzed three methods for the definition of ROIs based on probabilistic cytoarchitectonic maps. (1) ROIs defined by the volume assigned to a cytoarchitectonic area in the summary map of all areas (maximum probability map, MPM), (2) ROIs based on thresholding the individual probabilistic maps and (3) spherical ROIs build around the cytoarchitectonic center of gravity. The quality with which the thus defined ROIs represented the respective cytoarchitectonic areas as well as their sensitivity for detecting functional activations was subsequently statistically evaluated. Our data showed that the MPM method yields ROIs, which reflect most adequately the underlying anatomical hypotheses. These maps also show a high degree of sensitivity in the statistical analysis. We thus propose the use of MPMs for the definition of ROIs. In combination with thresholding based on the Gaussian random field theory, these ROIs can then be applied to test anatomically specified hypotheses in functional neuroimaging studies. PMID:16781166

  5. Animals' Use of Landmarks and Metric Information to Reorient: Effects of the Size of the Experimental Space

    Sovrano, Valeria Anna; Bisazza, Angelo; Vallortigara, Giorgio

    2005-01-01

    Disoriented children could use geometric information in combination with landmark information to reorient themselves in large but not in small experimental spaces. We tested fish in the same task and found that they were able to conjoin geometric and non-geometric (landmark) information to reorient themselves in both the large and the small space…

  6. 36 CFR 62.4 - Natural landmark designation and recognition process.

    2010-07-01

    ... sufficient representation of the significant natural features. (g) National Park System Advisory Board. (1... Board. The board reviews the information and recommends whether or not the land with consenting owners qualifies for national natural landmark designation. (2) Notice of Advisory Board meetings to...

  7. Landmarks in the Professional and Academic Development of Mid-Career Teacher Educators

    Griffiths, Vivienne; Thompson, Simon; Hryniewicz, Liz

    2014-01-01

    This paper focuses on the professional and academic development of mid-career teacher educators from two universities in England. The objectives of the study were to analyse and compare the career experiences of teacher educators; in particular, to identify stages of development, landmark events and contextual factors affecting professional…

  8. Obstacles Facing Promoting Tourism for Islamic Landmarks from the Perspective of Tour Operators in Egypt

    Suzan Bakri Hassan

    2015-05-01

    Full Text Available The UNESCO launched a campaign #unite4heritage in Egypt to defeat extremism and intolerance. The message of such campaigne is peace, dialogue and unity embedded in cultural heritage. As culture and tourism are linked together, such message could be delivered through improving culture heritage tourism in Egypt. Islamic landmarks  are considered as a part of human heritage. Therefore, the purpose of this study is to identify how much tour operators in Egypt include Islamic landmarks in their programs to determine the obstacles facing promoting cultural tourism in Islamic landmarks' areas. Additionally, the study would identify positive results in the case of developing heritage tourism in Egypt. To achieve a high result, a survey approach was employed to collect data from 100 tour operators, using a completed questionnaire technique as well as a Likert Scale and statistical models in order to test and interpret the research outcomes. The research findings indicated that although tour operators in Egypt are convinced of the significance of the Islamic landmarks, there is no contradiction between creating global understanding and at the same time achieving benefit to the local community. However, there is a range of obstacles facing promoting such type of tourism in Egypt. Keywords: Culture heritage tourism, community, Egypt, Islamic civilization.

  9. The developmental trajectory of intramaze and extramaze landmark biases in spatial navigation: An unexpected journey.

    Buckley, Matthew G; Haselgrove, Mark; Smith, Alastair D

    2015-06-01

    Adults learning to navigate to a hidden goal within an enclosed space have been found to prefer information provided by the distal cues of an environment, as opposed to proximal landmarks within the environment. Studies with children, however, have shown that 5- or 7-year-olds do not display any preference toward distal or proximal cues during navigation. This suggests that a bias toward learning about distal cues occurs somewhere between the age of 7 years and adulthood. We recruited 5- to 11-year-old children and an adult sample to explore the developmental profile of this putative change. Across a series of 3 experiments, participants were required to navigate to a hidden goal in a virtual environment, the location of which was signaled by both extramaze and intramaze landmark cues. During testing, these cues were placed into conflict to assess the search preferences of participants. Consistent with previously reported findings, adults were biased toward using extramaze information. However, analysis of the data from children, which incorporated age as a continuous variable, suggested that older children in our sample were, in fact, biased toward using the intramaze landmark in our task. These findings suggest the bias toward using distal cues in spatial navigation, frequently displayed by adults, may be a comparatively late developing trait, and one that could supersede an initial developmental preference for proximal landmarks. PMID:25844850

  10. Global Polity in Adult Education and UNESCO: Landmarking, Brokering and Framing Policy

    Milana, Marcella

    2016-01-01

    Aknowledging the complexity of local-global interconnections, the author argues for the adoption of a global polity perspective in adult education, here applied to study mobilisation processes that occur through UNESCO. The findings point to three processes that cross geopolitical borders and professional interests: "landmarking," by…

  11. Parallel striatal and hippocampal systems for landmarks and boundaries in spatial memory.

    Doeller, Christian F; King, John A; Burgess, Neil

    2008-04-15

    How the memory systems centered on the hippocampus and dorsal striatum interact to support behavior remains controversial. We used functional MRI while people learned the locations of objects by collecting and replacing them over multiple trials within a virtual environment comprising a landmark, a circular boundary, and distant cues for orientation. The relative location of landmark and boundary was occasionally changed, with specific objects paired with one or other cue, allowing dissociation of learning and performance relative to either cue. Right posterior hippocampal activation reflected learning and remembering of boundary-related locations, whereas right dorsal striatal activation reflected learning and remembering of landmark-related locations. Within the right hippocampus, anterior processing of environmental change (spatial novelty) was dissociated from posterior processing of location. Behavioral studies show that landmark-related learning obeys associative reinforcement, whereas boundary-related learning is incidental [Doeller CF, Burgess N (2008) Proc Natl Acad Sci USA 105:5909-5914]. The distinct incidental hippocampal processing of boundaries is suggestive of a "geometric module" or "cognitive map" and may explain the hippocampal support of incidental/observational learning in "declarative" or "episodic" memory versus the striatal support of trial-and-error learning in "procedural" memory. Finally, the hippocampal and striatal systems appear to combine "bottom-up," simply influencing behavior proportional to their activations, without direct interaction, with "top-down" ventromedial prefrontal involvement when both are similarly active. PMID:18408152

  12. An intelligent gradient detector with minimization of visual landmarks distortion for monitoring of passenger flows

    Gorbenko, A.; Popov, V.

    2013-01-01

    In this paper, we study the problem of monitoring of passenger flows. We consider an intelligent gradient algorithm to solve the problem. We use a method of minimization of visual landmarks distortion to improve the quality of recognition. © 2013 Anna Gorbenko and Vladimir Popov.

  13. Illusionary Inclusion--What Went Wrong with New Labour's Landmark Educational Policy?

    Hodkinson, Alan

    2012-01-01

    This article examines the emergence and evolution of New Labour's landmark educational policy; namely that of inclusion. The author, Alan Hodkinson, associate professor at the Centre for Cultural and Disability Studies at Liverpool Hope University, illuminates his conceptual difficulties in attempting to define what inclusion was and what…

  14. Lateral laryngopharyngeal diverticulum: anatomical and videofluoroscopic study

    Costa, Milton Melciades Barbosa [Universidade Federal do Rio de Janeiro ICB/CCS/UFRJ, Laboratorio de Motilidade Digestiva e Imagem, S. F1-008, Departamento de Anatomia, Rio de Janeiro (Brazil); Koch, Hilton Augusto [Universidade Federal do Rio de Janeiro ICB/CCS/UFRJ, Departamento de Radiologia, Rio de Janeiro (Brazil)

    2005-07-01

    The aims were to characterize the anatomical region where the lateral laryngopharyngeal protrusion occurs and to define if this protrusion is a normal or a pathological entity. This protrusion was observed on frontal contrasted radiographs as an addition image on the upper portion of the laryngopharynx. We carried out a plane-by-plane qualitative anatomical study through macroscopic and mesoscopic surgical dissection on 12 pieces and analyzed through a videofluoroscopic method on frontal incidence the pharyngeal phase of the swallowing process of 33 patients who had a lateral laryngopharyngeal protrusion. The anatomical study allowed us to identify the morphological characteristics that configure the high portion of the piriform recess as a weak anatomical point. The videofluoroscopic study allowed us to observe the laryngopharyngeal protrusion and its relation to pharyngeal repletion of the contrast medium. All kinds of the observed protrusions could be classified as ''lateral laryngopharyngeal diverticula.'' The lateral diverticula were more frequent in older people. These lateral protrusions can be found on one or both sides, usually with a small volume, without sex or side prevalence. This formation is probably a sign of a pharyngeal transference difficulty associated with a deficient tissue resistance in the weak anatomical point of the high portion of the piriform recess. (orig.)

  15. Characterization of Capsicum species using anatomical and molecular data.

    Dias, G B; Gomes, V M; Moraes, T M S; Zottich, U P; Rabelo, G R; Carvalho, A O; Moulin, M; Gonçalves, L S A; Rodrigues, R; Da Cunha, M

    2013-01-01

    Capsicum species are frequently described in terms of genetic divergence, considering morphological, agronomic, and molecular databases. However, descriptions of genetic differences based on anatomical characters are rare. We examined the anatomy and the micromorphology of vegetative and reproductive organs of several Capsicum species. Four Capsicum accessions representing the species C. annuum var. annuum, C. baccatum var. pendulum, C. chinense, and C. frutescens were cultivated in a greenhouse; leaves, fruits and seeds were sampled and their organ structure analyzed by light and scanning electronic microscopy. Molecular accession characterization was made using ISSR markers. Polymorphism was observed among tector trichomes and also in fruit color and shape. High variability among accessions was detected by ISSR markers. Despite the species studied present a wide morphological and molecular variability that was not reflected by anatomical features. PMID:23479174

  16. Detection and analysis of statistical differences in anatomical shape.

    Golland, Polina; Grimson, W Eric L; Shenton, Martha E; Kikinis, Ron

    2005-02-01

    We present a computational framework for image-based analysis and interpretation of statistical differences in anatomical shape between populations. Applications of such analysis include understanding developmental and anatomical aspects of disorders when comparing patients versus normal controls, studying morphological changes caused by aging, or even differences in normal anatomy, for example, differences between genders. Once a quantitative description of organ shape is extracted from input images, the problem of identifying differences between the two groups can be reduced to one of the classical questions in machine learning of constructing a classifier function for assigning new examples to one of the two groups while making as few misclassifications as possible. The resulting classifier must be interpreted in terms of shape differences between the two groups back in the image domain. We demonstrate a novel approach to such interpretation that allows us to argue about the identified shape differences in anatomically meaningful terms of organ deformation. Given a classifier function in the feature space, we derive a deformation that corresponds to the differences between the two classes while ignoring shape variability within each class. Based on this approach, we present a system for statistical shape analysis using distance transforms for shape representation and the support vector machines learning algorithm for the optimal classifier estimation and demonstrate it on artificially generated data sets, as well as real medical studies. PMID:15581813

  17. Bicycle Chain Shape Models

    Sommer, Stefan Horst; Tatu, Aditya Jayant; Chen, Chen;

    2009-01-01

    In this paper we introduce landmark-based preshapes which allow mixing of anatomical landmarks and pseudo-landmarks, constraining consecutive pseudo-landmarks to satisfy planar equidistance relations. This defines naturally a structure of Riemannian manifold on these preshapes, with a natural act...

  18. Shape-based diagnosis of the aortic valve

    Ionasec, Razvan Ioan; Tsymbal, Alexey; Vitanovski, Dime; Georgescu, Bogdan; Zhou, S. Kevin; Navab, Nassir; Comaniciu, Dorin

    2009-02-01

    Disorders of the aortic valve represent a common cardiovascular disease and an important public-health problem worldwide. Pathological valves are currently determined from 2D images through elaborate qualitative evalu- ations and complex measurements, potentially inaccurate and tedious to acquire. This paper presents a novel diagnostic method, which identies diseased valves based on 3D geometrical models constructed from volumetric data. A parametric model, which includes relevant anatomic landmarks as well as the aortic root and lea ets, represents the morphology of the aortic valve. Recently developed robust segmentation methods are applied to estimate the patient specic model parameters from end-diastolic cardiac CT volumes. A discriminative distance function, learned from equivalence constraints in the product space of shape coordinates, determines the corresponding pathology class based on the shape information encoded by the model. Experiments on a heterogeneous set of 63 patients aected by various diseases demonstrated the performance of our method with 94% correctly classied valves.

  19. Sensitivity of predicted muscle forces during gait to anatomical variability in musculotendon geometry.

    Bosmans, Lode; Valente, Giordano; Wesseling, Mariska; Van Campen, Anke; De Groote, Friedl; De Schutter, Joris; Jonkers, Ilse

    2015-07-16

    Scaled generic musculoskeletal models are commonly used to drive dynamic simulations of motions. It is however, acknowledged that not accounting for variability in musculoskeletal geometry and musculotendon parameters may confound the simulation results, even when analysing control subjects. This study documents the three-dimensional anatomical variability of musculotendon origins and insertions of 33 lower limb muscles determined based on magnetic resonance imaging in six subjects. This anatomical variability was compared to the musculotendon point location in a generic musculoskeletal model. Furthermore, the sensitivity of muscle forces during gait, calculated using static optimization, to perturbations of the musculotendon point location was analyzed with a generic model. More specific, a probabilistic approach was used: for each analyzed musculotendon point, the three-dimensional location was re-sampled with a uniform Latin hypercube method within the anatomical variability and the static optimization problem was then re-solved for all perturbations. We found that musculotendon point locations in the generic model showed only variable correspondences with the anatomical variability. The anatomical variability of musculotendon point location did affect the calculated muscle forces: muscles most sensitive to perturbations within the anatomical variability are iliacus and psoas. Perturbation of the gluteus medius anterior, iliacus and psoas induces the largest concomitant changes in muscle forces of the unperturbed muscles. Therefore, when creating subject-specific musculoskeletal models, these attachment points should be defined accurately. In addition, the size of the anatomical variability of the musculotendon point location was not related to the sensitivity of the calculated muscle forces. PMID:25979383

  20. Congenital neck masses: embryological and anatomical perspectives

    Zahida Rasool

    2013-08-01

    Full Text Available Neck masses are a common problem in paediatric age group. They tend to occur frequently and pose a diagnostic dilemma to the ENT surgeons. Although the midline and lateral neck masses differ considerably in their texture and presentation but the embryological perspective of these masses is not mostly understood along with the fundamental anatomical knowledge. The article tries to correlate the embryological, anatomical and clinical perspectives for the same. [Int J Res Med Sci 2013; 1(4.000: 329-332

  1. Marginal space learning for medical image analysis efficient detection and segmentation of anatomical structures

    Zheng, Yefeng

    2014-01-01

    Presents an award winning image analysis technology (Thomas Edison Patent Award, MICCAI Young Investigator Award) that achieves object detection and segmentation with state-of-the-art accuracy and efficiency Flexible, machine learning-based framework, applicable across multiple anatomical structures and imaging modalities Thirty five clinical applications on detecting and segmenting anatomical structures such as heart chambers and valves, blood vessels, liver, kidney, prostate, lymph nodes, and sub-cortical brain structures, in CT, MRI, X-Ray and Ultrasound.

  2. Evaluation of association between mandibular crowding and some of anatomical indexes in skeletal Cl II 8-12 years old patient with mandibular deficiency

    Shirazi Mohsen

    2015-05-01

    Full Text Available Tehran University of Medical Sciences, Tehran, Iran ( mirahashemi@tums.ac.ir   Background and Aims: Nowadays patients refer to orthodontist for issue such as dental crowding and other aesthetic problems. The aims of this study were to evaluate the relationship between some of mandibular anatomical landmarks and dental crowding in the patient with skeletal Cl II due to mandibular deficiency.   Materials and Methods: 108 cases have been randomly selected out of patients with mandibular related Cl II problem associated with lower incisor crowding, out of orthodontic patient department of Tehran university of medical sciences. ANB, SNB, mandibular discrepancy, gonial angle, Sn-Go-Gn and IMPA was evaluated out of the data. Lateral cephalograms were used for this matter. The correlation between variables was evaluated by correlation test and after reviewing the data was analyzed using Normality test, the Pearson correlation coefficient was used for normally distributed variables.   Results: Corpus-ramus length ratio had a significant relationship with dental crowding (P≤0.05 but there was no meaningful and significant relationship between other facial landmarks ( P = 0.26 .   Conclusion: there seems to be a slight relationship between facial landmarks and dental crowding in lower incisors. But further case control and clinical studies may be helpful in achieving more reliable data.

  3. Anatomical aspect of the hard palate of the Cebus apella (Linnaeus, 1766 primates

    Andréia Luciana Martins Ramos

    2008-03-01

    Full Text Available Fourteen hard palates of neotropical primates were studied (Cebus apella, fixed on formaldehyde (10% and preserved in ethylic alcohol (70%, collected according to the International Bioethics Committee. The animals were supplied by the Medicine College Veterinary Medicine and Zootecnica of the University of São Paulo in 1994. They originated from the São Paulo Zoo. They had died naturally. Measurement (in centimeters of the viscerocranium (8 adults and 6 young animals was made, including palatine length (PL, interpremolar distance (ID, intermolar distance (ID, interorbital distance (IDi, and midface height (MH. The palatine anatomy showed complete right crests (7.64 to 1.22, complete left crests (8.07 to 1.71, incomplete right crests (1.71 to 1.43, and incomplete left crests (1.64 to 1.3. The diasten between the lateral incisive teeth was the main anatomical landmark for the anterior end of the crest, and the landmark for the posterior end was the second molar teeth for all the specimens. The palate is very peculiar: mild concave, from the dental arcade to the median line, covered by the non-pigmented mucous tissue, with osseous structure composed of horizontal layers of the maxilar and palatine bones; sub mucous tissue attached to the periosteum and mucous tissue showing relatively prominent palatine crests. The crests appear as a rigid elevation of the mucous tissue, with some variations at the antimers. It may be concluded that the length of the hard palate is strongly related to the maturity of the animal, relative to the interorbital distance, and that the latter is also related to the length of the palate and the labial opening.

  4. Identifying characteristic back shapes from anatomical scans of wheelchair users to improve seating design.

    Crytzer, Theresa M; Hong, Eun-Kyoung; Dicianno, Brad E; Pearlman, Jon; Schmeler, Mark; Cooper, Rory A

    2016-09-01

    Spinal deformities are common in people who require the use of a wheelchair for mobility as a result of spinal cord injuries and other disabilities. Sitting positions vary between individuals with disabilities who use wheelchairs and individuals without disabilities. In individuals with spinal cord injury, spinal deformities can result in the development of back contours that deviate from the shape of standard rigid back support shells. The purpose of this study was to distinguish and classify various back contours of wheelchair users by utilizing digital anatomic scanning technology in order to inform the future development of back supports that would enhance postural support for those with spinal deformities. The three dimensional (3D) locations of bony landmarks were digitized when participants were in position, using a mechanical wand linked to the FastScan(tm) system commonly used to measure surface contours. Raw FastScan(tm) data were transformed according to bony landmarks. A total of 129 individuals participated in this study. A wide range of back contours were identified and categorized. Although participant characteristics (e.g., gender, diagnosis) were similar amongst the contour groups; no one characteristic explained the contours. Participants who were seated in a forward lean position had a higher amount of pelvic obliquity compared to those seated in an upright position; however, participants' back contour was not correlated with pelvic obliquity. In conclusion, an array of different back shapes were classified in our cohort through 3D laser scanning technology. The methods and technology applied in this study could be replicated in future studies to categorize ranges of back shapes in larger populations of people with spinal cord injuries. Preliminary evidence indicates that customized postural support may be warranted to optimize positioning and posture when a standard rigid shell does not align with contours of a person's back. To optimize

  5. Report of a rare anatomic variant

    De Brucker, Y; Ilsen, B; Muylaert, C;

    2015-01-01

    We report the CT findings in a case of partial anomalous pulmonary venous return (PAPVR) from the left upper lobe in an adult. PAPVR is an anatomic variant in which one to three pulmonary veins drain into the right atrium or its tributaries, rather than into the left atrium. This results in a lef...

  6. Evolution of the Anatomical Theatre in Padova

    Macchi, Veronica; Porzionato, Andrea; Stecco, Carla; Caro, Raffaele

    2014-01-01

    The anatomical theatre played a pivotal role in the evolution of medical education, allowing students to directly observe and participate in the process of dissection. Due to the increase of training programs in clinical anatomy, the Institute of Human Anatomy at the University of Padova has renovated its dissecting room. The main guidelines in…

  7. Magnetic resonance angiography: infrequent anatomic variants

    We studied through RM angiography (3D TOF) with high magnetic field equipment (1.5 T) different infrequent intracerebral vascular anatomic variants. For their detection we emphasise the value of post-processed images obtained after conventional angiographic sequences. These post-processed images should be included in routine protocols for evaluation of the intracerebral vascular structures. (author)

  8. HPV Vaccine Effective at Multiple Anatomic Sites

    A new study from NCI researchers finds that the HPV vaccine protects young women from infection with high-risk HPV types at the three primary anatomic sites where persistent HPV infections can cause cancer. The multi-site protection also was observed at l

  9. Handbook of anatomical models for radiation dosimetry

    Eckerman, Keith F

    2010-01-01

    Covering the history of human model development, this title presents the major anatomical and physical models that have been developed for human body radiation protection, diagnostic imaging, and nuclear medicine therapy. It explores how these models have evolved and the role that modern technologies have played in this development.

  10. Anatomical characteristics of lingual artery in physiological condition and its relationship with tongue base%生理状态下舌动脉的解剖特点及其与舌根的关系

    龚明杰; 邹嘉平; 王均干

    2012-01-01

    Objective:To provide the clinical anatomic data of the lingual artery with 3D CT reconstruction. Method:Ten healthy subjects were recruited. Spiral CT scan ranged from the sternoclavicular joint to the lower edge of the orbit and the data was subjected to three-dimensional reconstruction. The distance from the origin of the lingual artery to the bifurcation of the common carotid artery and tip of the greater horn of hyoid bone were measured respectively and the distance between the midline of the lingual artery and the midline of tongue were also measured. Result: The horizontal distance between starting level of lingual artery to the level of the hyoid horn tip was(l. 51±0. 35)cm. The horizontal distance between the level of the lingual artery to the carotid bifurcation was(0.95±0.31)cm. The comparison of the distance from lingual artery 1 cm anterior or posterior to foramen ce-cum to midline of tongue showed (t = 45. 27,P<0. 01)a statistically significant difference.Conclusion:The lingual artery could be demonstrated clearly in 3D reconstruction. To ensure the operative safety, the depth of radiofre-quency for OSAHS at the tongue base should be limited within 2 centimeters.%目的:通过CT三维重建技术,对舌动脉的起源、分段和走行进行研究,探讨其位置关系在临床中的作用.方法:选取10例健康人,CT扫描范围从胸锁关节至眼眶下缘,数据传送到工作站进行三维重建.同时测量舌动脉起始点水平到舌骨大角尖端水平及到颈动脉分叉水平的垂直距离,以及舌动脉与舌表面和舌中线的距离.结果:舌动脉起始点水平到舌骨大角尖端水平的垂直距离为(1.51±0.35)cm,舌动脉起始点水平到颈动脉分叉水平的垂直距离为(0.95±0.31)cm;在舌盲孔前1 cm与舌盲孔后1 cm的舌动脉与舌中线距离比较,差异有统计学意义(t=45.27,P<0.01).结论:舌动脉以舌骨大角为标志的分段法更符合舌动脉走行变异大的特点.在进行舌

  11. Age-Related Differences in Associative Learning of Landmarks and Heading Directions in a Virtual Navigation Task.

    Zhong, Jimmy Y; Moffat, Scott D

    2016-01-01

    Previous studies have showed that spatial memory declines with age but have not clarified the relevance of different landmark cues for specifying heading directions among different age groups. This study examined differences between younger, middle-aged and older adults in route learning and memory tasks after they navigated a virtual maze that contained: (a) critical landmarks that were located at decision points (i.e., intersections) and (b) non-critical landmarks that were located at non-decision points (i.e., the sides of the route). Participants were given a recognition memory test for critical and non-critical landmarks and also given a landmark-direction associative learning task. Compared to younger adults, older adults committed more navigation errors during route learning and were poorer at associating the correct heading directions with both critical and non-critical landmarks. Notably, older adults exhibited a landmark-direction associative memory deficit at decision points; this was the first finding to show that an associative memory deficit exist among older adults in a navigational context for landmarks that are pertinent for reaching a goal, and suggest that older adults may expend more cognitive resources on the encoding of landmark/object features than on the binding of landmark and directional information. This study is also the first to show that older adults did not have a tendency to process non-critical landmarks, which were regarded as distractors/irrelevant cues for specifying the directions to reach the goal, to an equivalent or larger extent than younger adults. We explain this finding in view of the low number of non-critical cues in our virtual maze (relative to a real-world urban environment) that might not have evoked older adults' usual tendency toward processing or encoding distractors. We explain the age differences in navigational and cognitive performance with regards to functional and structural changes in the hippocampus and

  12. Functional Versus Anatomic Imaging of CAD: Lessons Learned from Recent Clinical Trials.

    Gewirtz, Henry

    2016-01-01

    Recent clinical trials directed at imaging of coronary artery disease (CAD) have demonstrated a paradigm shift away from endpoints related to detection of CAD in favor of those related to clinical outcomes. The objective of such trials has been to determine whether physiological metrics are superior to anatomical ones for guiding therapy and improving outcomes in patients with known or suspected CAD. The present review focuses on selected trials in this area in particular DEFER, FAME 1 and 2, a meta-analysis comparing FFR to anatomically guided treatment outcomes and COURAGE SPECT MPI sub study. The rationale for using physiological as opposed to anatomical endpoints to optimize patient management, in particular coronary revascularization decisions, is emphasized. The results of the FFR-based trials are concordant and indicate physiological metrics are superior to anatomical ones for guiding therapy and improving clinical outcomes in patients with known or suspected CAD. PMID:26699631

  13. Rhizosphere of Avicennia marina (Forsk.) Vierh. as a landmark for polythene degrading bacteria.

    Shahnawaz, Mohd; Sangale, Manisha K; Ade, Avinash B

    2016-07-01

    Due to high durability, cheap cost, and ease of manufacture, 311 million tons of plastic-based products are manufactured around the globe per annum. The slow/least rate of plastic degradation leads to generation of million tons of plastic waste per annum, which is of great environmental concern. Of the total plastic waste generated, polythene shared about 64 %. Various methods are available in the literature to tackle with the plastic waste, and biodegradation is considered as the most accepted, eco-friendly, and cost-effective method of polythene waste disposal. In the present study, an attempt has been made to isolate, screen, and characterize the most efficient polythene degrading bacteria by using rhizosphere soil of Avicennia marina as a landmark. From 12 localities along the west coast of India, a total of 123 bacterial isolates were recorded. Maximum percent weight loss (% WL; 21.87 ± 6.37 %) was recorded with VASB14 at pH 3.5 after 2 months of shaking at room temperature. Maximum percent weight gain (13.87 ± 3.6 %) was reported with MANGB5 at pH 7. Maximum percent loss in tensile strength (% loss in TS; 87.50 ± 4.8 %) was documented with VASB1 at pH 9.5. The results based on the % loss in TS were only reproducible. Further, the level of degradation was confirmed by scanning electron microscopic (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. In SEM analysis, scions/crakes were found on the surface of the degraded polythene, and mass of bacterial cell was also recorded on the weight-gained polythene strips. Maximum reduction in carbonyl index (4.14 %) was recorded in untreated polythene strip with Lysinibacillus fusiformis strain VASB14/WL. Based on 16S ribosomal RNA (rRNA) gene sequence homology, the most efficient polythene degrading bacteria were identified as L. fusiformis strainVASB14/WL and Bacillus cereus strain VASB1/TS. PMID:27072028

  14. Hoffa's fat pad injuries and their relationship with anterior cruciate ligament tears: new observations based on MR imaging in patients and MR imaging and anatomic correlation in cadavers

    Abreu, Marcelo R. [University of California San Diego, VA Health Care System, San Diego, CA (United States); Chung, Christine B.; Trudell, Debra; Resnick, Donald [University of California San Diego, VA Health Care System, San Diego, CA (United States); Hospital Mae de Deus, Porto Alegre, RS (Brazil)

    2008-04-15

    To determine the normal anatomic relationships of Hoffa's fat pad with the anterior cruciate ligament (ACL) and with the frequency of Hoffa's fat pad abnormalities in ACL-deficient knees. Retrospective clinical study on patients and observational anatomic study on cadavers. The study was approved by the Institutional Review Board. MR imaging studies of the knees of 100 patients (21-48 years old) with or without arthroscopically proven tears of the ACL, performed at a single institution, were reviewed by two readers for abnormalities of Hoffa's fat pad. Ten cadaveric knee specimens were studied with MR imaging and Faxitron radiographs, and by inspection of sections and histology. Alterations in Hoffa's fat pad on MR imaging were present in 64% (32/50) of patients with torn ACLs, and in 24% (12/50) of patients without a tear of the ACL (P < 0.05). Hoffa's fat pad inserted into the intercondylar notch in 50% (5/10) of cadaveric specimens, four in conjunction with the ligamentum mucosum and in one in an isolated fashion. Histological study demonstrated the composition of the ligamentum mucosum and Hoffa's fat pad and their course and insertion sites in the intercondylar notch. Abnormalities of Hoffa's fat pad, such as focal and diffuse edema, tears, scars and synovial proliferation, are more common in knees with torn ACLs than in knees with intact ACLs. (orig.)

  15. Accurate definition of brain regions position through the functional landmark approach.

    Thirion, Bertrand; Varoquaux, Gaël; Poline, Jean-Baptiste

    2010-01-01

    In many application of functional Magnetic Resonance Imaging (fMRI), including clinical or pharmacological studies, the definition of the location of the functional activity between subjects is crucial. While current acquisition and normalization procedures improve the accuracy of the functional signal localization, it is also important to ensure that functional foci detection yields accurate results, and reflects between-subject variability. Here we introduce a fast functional landmark detection procedure, that explicitly models the spatial variability of activation foci in the observed population. We compare this detection approach to standard statistical maps peak extraction procedures: we show that it yields more accurate results on simulations, and more reproducible results on a large cohort of subjects. These results demonstrate that explicit functional landmark modeling approaches are more effective than standard statistical mapping for brain functional focus detection. PMID:20879321

  16. Development of a landmark recognition system for the posture measurement of mobile robots

    A landmark recognition system, consisting of retroreflective landmarks, a CCD camera, a strobe unit, an image processing board, and processing software, has been developed to solve the problem of the posture (position and orientation) identification of mobile robots in manufacturing environments. The binary image processing technique instead of gray image technique has been adapted in this system to perform the fast posture measurement of the robots. The experimental results demonstrated real-time measurement capability of this system while maintaining good reliability and reasonable accuracy. A camera calibration technique has been described to reduce the effects of unwanted measurement error sources. The system after camera calibration procedure has demonstrated enhanced performance in terms of error component in posture measurement. (Author)

  17. Landmarks of Contemporary Fiscal Policy in The European Union

    Ionuţ-Cătălin CROITORU

    2011-01-01

    Fiscal policy is one of the key concerns of each state and one of the direct ways to influence economic development. Therefore, a well-based fiscal policy that takes into account the specific conditions of economic and social imperatives of the present and future requirements, it may prove beneficial for progress. This paper aims to trace the main features of modern tax policy and make an analysis of the evolution of direct and indirect taxes in Europe. The analysis includes the role attribut...

  18. Navigation in wood ants Formica japonica: context dependent use of landmarks.

    Fukushi, T; Wehner, R.

    2004-01-01

    Wood ants Formica japonica can steer their outbound (foraging) and inbound (homing) courses without using celestial compass information, by relying exclusively on landmark cues. This is shown by training ants to run back and forth between the nest and an artificial feeder, and later displacing the trained ants either from the nest (when starting their foraging runs: outbound full-vector ants) or from the feeder (when starting their home runs: inbound full-vector ants) to various nearby releas...

  19. Superficial cortical landmarks for localization of the hippocampus: Application for temporal lobectomy and amygdalohippocampectomy

    R. Shane Tubbs; Marios Loukas; Barbaro, Nicholas M.; Aaron A Cohen-Gadol

    2015-01-01

    Background: Accessing the hippocampus for amygdalohippocampectomy and procedures such as depth electrode placement requires accurate knowledge regarding the location of the hippocampus. Methods: The authors removed 10 human cadaveric brains (20 sides) from their crania, noted relationships between the lateral temporal neocortex and underlying hippocampus, and measured the distance between the hippocampus and superficial landmarks. Results: Mean distances were as follows: 3.8 cm from t...

  20. Cell cycle dynamics of histone variants at the centromere, a model for chromosomal landmarks.

    Boyarchuk, Ekaterina; Montes De Oca, Rocío; Almouzni, Geneviève

    2011-01-01

    Classical heterochromatin chromosomal landmarks, such as centromeres and telomeres, are characterized by specific chromatin signatures. Among these, the incorporation of histone variants has recently emerged as an important feature. Using the centromere as a paradigm, we consider the role of histone variant dynamics in locus-specific chromatin organization. We describe the distinct location and dynamics of CenH3, H3.3, and H2AZ at the centromere during the cell cycle. This leads us to present...

  1. Automatic landmark annotation and dense correspondence registration for 3D human facial images

    Guo, Jianya; Mei, Xi; Tang, Kun

    2012-01-01

    Background Traditional anthropometric studies of human face rely on manual measurements of simple features, which are labor intensive and lack of full comprehensive inference. Dense surface registration of three-dimensional (3D) human facial images holds great potential for high throughput quantitative analyses of complex facial traits. However there is a lack of automatic high density registration method for 3D faical images. Furthermore, current approaches of landmark recognition require fu...

  2. Historical evolution of anatomical terminology from ancient to modern.

    Sakai, Tatsuo

    2007-06-01

    The historical development of anatomical terminology from the ancient to the modern can be divided into five stages. The initial stage is represented by the oldest extant anatomical treatises by Galen of Pergamon in the Roman Empire. The anatomical descriptions by Galen utilized only a limited number of anatomical terms, which were essentially colloquial words in the Greek of this period. In the second stage, Vesalius in the early 16th century described the anatomical structures in his Fabrica with the help of detailed magnificent illustrations. He coined substantially no anatomical terms, but devised a system that distinguished anatomical structures with ordinal numbers. The third stage of development in the late 16th century was marked by innovation of a large number of specific anatomical terms especially for the muscles, vessels and nerves. The main figures at this stage were Sylvius in Paris and Bauhin in Basel. In the fourth stage between Bauhin and the international anatomical terminology, many anatomical textbooks were written mainly in Latin in the 17th century, and in modern languages in the 18th and 19th centuries. Anatomical terms for the same structure were differently expressed by different authors. The last stage began at the end of the 19th century, when the first international anatomical terminology in Latin was published as Nomina anatomica. The anatomical terminology was revised repeatedly until the current Terminologia anatomica both in Latin and English. PMID:17585563

  3. Molecular architecture of classical cytological landmarks: Centromeres and telomeres

    Meyne, J.

    1994-11-01

    Both the human telomere repeat and the pericentromeric repeat sequence (GGAAT)n were isolated based on evolutionary conservation. Their isolation was based on the premise that chromosomal features as structurally and functionally important as telomeres and centromeres should be highly conserved. Both sequences were isolated by high stringency screening of a human repetitive DNA library with rodent repetitive DNA. The pHuR library (plasmid Human Repeat) used for this project was enriched for repetitive DNA by using a modification of the standard DNA library preparation method. Usually DNA for a library is cut with restriction enzymes, packaged, infected, and the library is screened. A problem with this approach is that many tandem repeats don`t have any (or many) common restriction sites. Therefore, many of the repeat sequences will not be represented in the library because they are not restricted to a viable length for the vector used. To prepare the pHuR library, human DNA was mechanically sheared to a small size. These relatively short DNA fragments were denatured and then renatured to C{sub o}t 50. Theoretically only repetitive DNA sequences should renature under C{sub o}t 50 conditions. The single-stranded regions were digested using S1 nuclease, leaving the double-stranded, renatured repeat sequences.

  4. Eyewitness to history: Landmarks in the development of computerized electrocardiography.

    Rautaharju, Pentti M

    2016-01-01

    The use of digital computers for ECG processing was pioneered in the early 1960s by two immigrants to the US, Hubert Pipberger, who initiated a collaborative VA project to collect an ECG-independent Frank lead data base, and Cesar Caceres at NIH who selected for his ECAN program standard 12-lead ECGs processed as single leads. Ray Bonner in the early 1970s placed his IBM 5880 program in a cart to print ECGs with interpretation, and computer-ECG programs were developed by Telemed, Marquette, HP-Philips and Mortara. The "Common Standards for quantitative Electrocardiography (CSE)" directed by Jos Willems evaluated nine ECG programs and eight cardiologists in clinically-defined categories. The total accuracy by a representative "average" cardiologist (75.5%) was 5.8% higher than that of the average program (69.7, pcomputer-based and expert reader performance are likely to show evolving results with continuing improvement of computer-ECG algorithms and changing expertise of ECG interpreters. PMID:26620728

  5. Design of an enhanced visual odometry by building and matching compressive panoramic landmarks online

    Wei LU; Zhi-yu XIANG; Ji-lin LIU

    2015-01-01

    Efficient and precise localization is a prerequisite for the intelligent navigation of mobile robots. Traditional visual localization systems, such as visual odometry (VO) and simultaneous localization and mapping (SLAM), suffer from two short-comings: a drift problem caused by accumulated localization error, and erroneous motion estimation due to illumination varia-tion and moving objects. In this paper, we propose an enhanced VO by introducing a panoramic camera into the traditional stereo-only VO system. Benefiting from the 360° field of view, the panoramic camera is responsible for three tasks: (1) detect-ing road junctions and building a landmark library online; (2) correcting the robot’s position when the landmarks are revisited with any orientation; (3) working as a panoramic compass when the stereo VO cannot provide reliable positioning results. To use the large-sized panoramic images efficiently, the concept of compressed sensing is introduced into the solution and an adap-tive compressive feature is presented. Combined with our previous two-stage local binocular bundle adjustment (TLBBA) stereo VO, the new system can obtain reliable positioning results in quasi-real time. Experimental results of challenging long-range tests show that our enhanced VO is much more accurate and robust than the traditional VO, thanks to the compressive panoramic landmarks built online.

  6. A low-cost test-bed for real-time landmark tracking

    Csaszar, Ambrus; Hanan, Jay C.; Moreels, Pierre; Assad, Christopher

    2007-04-01

    A low-cost vehicle test-bed system was developed to iteratively test, refine and demonstrate navigation algorithms before attempting to transfer the algorithms to more advanced rover prototypes. The platform used here was a modified radio controlled (RC) car. A microcontroller board and onboard laptop computer allow for either autonomous or remote operation via a computer workstation. The sensors onboard the vehicle represent the types currently used on NASA-JPL rover prototypes. For dead-reckoning navigation, optical wheel encoders, a single axis gyroscope, and 2-axis accelerometer were used. An ultrasound ranger is available to calculate distance as a substitute for the stereo vision systems presently used on rovers. The prototype also carries a small laptop computer with a USB camera and wireless transmitter to send real time video to an off-board computer. A real-time user interface was implemented that combines an automatic image feature selector, tracking parameter controls, streaming video viewer, and user generated or autonomous driving commands. Using the test-bed, real-time landmark tracking was demonstrated by autonomously driving the vehicle through the JPL Mars yard. The algorithms tracked rocks as waypoints. This generated coordinates calculating relative motion and visually servoing to science targets. A limitation for the current system is serial computing-each additional landmark is tracked in order-but since each landmark is tracked independently, if transferred to appropriate parallel hardware, adding targets would not significantly diminish system speed.

  7. Some scientific landmarks of the MIT radium toxicity studies

    Maletskos, C.J. [Constantine Maletskos, Gloucester, MA (United States)

    1996-12-31

    Until the recent forced termination of the studies on radium toxicity, more than six decades of investigation and research have been devoted to them. These studies involve {approximately}2400 subjects who were exposed to long-term internally deposited radium [high linear energy transfer (LET)], whose health status was evaluated in great detail and whose radiation dosimetry was based on measurements of their actual radium body burdens. The quality and usefulness of these studies are, therefore, in sharp contrast to other human radiation-exposure studies that involve instantaneous or somewhat protracted external low-LET exposures and inferred radiation dose, as in the atomic-bomb survivor studies. As a consequence of national news in 1932 concerning the gruesome death of a prominent Pittsburgh businessman and sportsman, Robley D. Evans became involved with radium toxicity, and its study became an important project when he joined the faculty of the Massachusetts Institute of Technology physics department and set up the interdisciplinary Radioactivity Center.

  8. Freehand Thoracic Pedicle Screw Placement: Review of Existing Strategies and a Step-by-Step Guide Using Uniform Landmarks for All Levels.

    Avila, Mauricio J; Baaj, Ali A

    2016-01-01

    Pedicle screw fixation in the thoracic spine presents certain challenges due to the critical regional neurovascular anatomy as well as the narrow pedicular corridor that typically exists. With increased awareness of the dangers of intraoperative radiation, the ability to place pedicle screws with anatomic landmarks alone is paramount. In this study, we reviewed the literature from 1990 to 2015 for studies that included freehand pedicle screw placement in the thoracic spine with special emphasis on entry points and the trajectories of the screws. We excluded studies that used fluoroscopy guidance, navigation techniques, cadaveric and biomechanical articles, case reports, and experimental studies on animals. The search retrieved 40 articles, and after careful selection, seven articles were analyzed. Over 8,000 screws were placed in the different studies. The mean accuracy for placement of the thoracic screws was 93.3%. However, there is little consensus between studies in entry points, sagittal, and axial trajectories of the screws. We complete this review by presenting our step-by-step technique for the placement of freehand pedicle screws in the thoracic spine. PMID:27014535

  9. ANATOMIC RESEARCH OF SUPERIOR CLUNIAL NERVE TRAUMA

    1999-01-01

    In order to find the mechanism of superior clunial nerve (SCN) trauma, we dissected and revealed SCN from 12 corpses (24 sides). Combining 100 sides of SCN trauma, we inspected the course of SCN, the relation between SCN and it's neighbour tissues with the situation of SCN when being subjected to force. We found that the following special anatomic characteristics and mechanical elements such as the course of SCN, it's turning angles, the bony fibrous tube at the iliac crest, the posterior layer of the lumbodorsal fascia and SCN neighbour adipose tissue, are the causes of external force inducing SCN trauma. The anatomic revealment is the guidance of SCN trauma treatment with edged needle.

  10. Increased cortical-limbic anatomical network connectivity in major depression revealed by diffusion tensor imaging.

    Peng Fang

    Full Text Available Magnetic resonance imaging studies have reported significant functional and structural differences between depressed patients and controls. Little attention has been given, however, to the abnormalities in anatomical connectivity in depressed patients. In the present study, we aim to investigate the alterations in connectivity of whole-brain anatomical networks in those suffering from major depression by using machine learning approaches. Brain anatomical networks were extracted from diffusion magnetic resonance images obtained from both 22 first-episode, treatment-naive adults with major depressive disorder and 26 matched healthy controls. Using machine learning approaches, we differentiated depressed patients from healthy controls based on their whole-brain anatomical connectivity patterns and identified the most discriminating features that represent between-group differences. Classification results showed that 91.7% (patients=86.4%, controls=96.2%; permutation test, p<0.0001 of subjects were correctly classified via leave-one-out cross-validation. Moreover, the strengths of all the most discriminating connections were increased in depressed patients relative to the controls, and these connections were primarily located within the cortical-limbic network, especially the frontal-limbic network. These results not only provide initial steps toward the development of neurobiological diagnostic markers for major depressive disorder, but also suggest that abnormal cortical-limbic anatomical networks may contribute to the anatomical basis of emotional dysregulation and cognitive impairments associated with this disease.

  11. Strong links between genomic and anatomical diversity in both mammalian olfactory chemosensory systems.

    Garrett, Eva C; Steiper, Michael E

    2014-05-22

    Mammalian olfaction comprises two chemosensory systems: the odorant-detecting main olfactory system (MOS) and the pheromone-detecting vomeronasal system (VNS). Mammals are diverse in their anatomical and genomic emphases on olfactory chemosensation, including the loss or reduction of these systems in some orders. Despite qualitative evidence linking the genomic evolution of the olfactory systems to specific functions and phenotypes, little work has quantitatively tested whether the genomic aspects of the mammalian olfactory chemosensory systems are correlated to anatomical diversity. We show that the genomic and anatomical variation in these systems is tightly linked in both the VNS and the MOS, though the signature of selection is different in each system. Specifically, the MOS appears to vary based on absolute organ and gene family size while the VNS appears to vary according to the relative proportion of functional genes and relative anatomical size and complexity. Furthermore, there is little evidence that these two systems are evolving in a linked fashion. The relationships between genomic and anatomical diversity strongly support a role for natural selection in shaping both the anatomical and genomic evolution of the olfactory chemosensory systems in mammals. PMID:24718758

  12. Anatomical basis for impotence following haemorrhoid sclerotherapy.

    Pilkington, S. A.; Bateman, A C; Wombwell, S.; Miller, R

    2000-01-01

    Impotence has been reported as a rare but important complication of sclerotherapy for haemorrhoids. The relationship between the anterior wall of the rectum and the periprostatic parasympathetic nerves responsible for penile erection was studied to investigate a potential anatomical explanation for this therapeutic complication. A tissue block containing the anal canal, rectum and prostate was removed from each of six male cadaveric subjects. The dimensions of the components of the rectal wal...

  13. Identification of anatomical terminology in medical text.

    Sneiderman, C. A.; Rindflesch, T. C.; Bean, C. A.

    1998-01-01

    We report on an experiment to use the natural language processing tools being developed in the SPECIALIST system to accurately identify terminology associated with the coronary arteries as expressed in coronary catheterization reports. The ultimate goal is to map from any anatomically-oriented medical text to online images, using the UMLS as an intermediate knowledge source. We describe some of the problems encountered when processing coronary artery terminology and report on the results of a...

  14. Microstructure and Anatomical Characteristics of Daemonorops margaritae

    2008-01-01

    Daemonorops margaritae is among the most important commercial rattan in South China. Its microstructure and basic anatomical characteristics as well as variation were investigated. Results show that: 1)The variation along the height is small, while the variation along the radial direction is significant; 2) The fibre length, fibre ratio and distribution density of the vascular bundles in the cross section decrease from cortex to core, while the fibre width, vessel element length and width, parenchyma ratio,...

  15. Pure endoscopic endonasal odontoidectomy: anatomical study

    Messina, Andrea; Bruno, Maria Carmela; Decq, Philippe; Coste, Andre; Cavallo, Luigi Maria; de Divittis, Enrico; Cappabianca, Paolo; Tschabitscher, Manfred

    2007-01-01

    Different disorders may produce irreducible atlanto-axial dislocation with compression of the ventral spinal cord. Among the surgical approaches available for a such condition, the transoral resection of the odontoid process is the most often used. The aim of this anatomical study is to demonstrate the possibility of an anterior cervico-medullary decompression through an endoscopic endonasal approach. Three fresh cadaver heads were used. A modified endonasal endoscopic approach was made in al...

  16. ACCESSORY SPLEEN: A CLINICALLY RELEVANT ANATOMIC ANOMALY

    Prachi Saffar; Amit Kumar; Ankur

    2016-01-01

    The purpose of our study is to emphasize on the clinical relevance of the presence of accessory spleen. It is not only a well-documented anatomic anomaly, it holds special significance in the differential diagnosis of intra-abdominal tumours and lymphadenopathy. MATERIALS AND METHODS Thirty male cadavers from North Indian population above the age of 60 yrs. were dissected in the Anatomy Department of FMHS, SGT University, Gurgaon, over a period of 5 yrs. (Sep 2010-Aug 2015) and presence...

  17. Anatomical MRI with an atomic magnetometer

    Savukov, I

    2012-01-01

    Ultra-low field (ULF) MRI is a promising method for inexpensive medical imaging with various additional advantages over conventional instruments such as low weight, low power, portability, absence of artifacts from metals, and high contrast. Anatomical ULF MRI has been successfully implemented with SQUIDs, but SQUIDs have the drawback of cryogen requirement. Atomic magnetometers have sensitivity comparable to SQUIDs and can be in principle used for ULF MRI to replace SQUIDs. Unfortunately some problems exist due to the sensitivity of atomic magnetometers to magnetic field and gradients. At low frequency, noise is also substantial and a shielded room is needed for improving sensitivity. In this paper, we show that at 85 kHz, the atomic magnetometer can be used to obtain anatomical images. This is the first demonstration of any use of atomic magnetometers for anatomical MRI. The demonstrated resolution is 1.1x1.4 mm2 in about six minutes of acquisition with SNR of 10. Some applications of the method are discuss...

  18. Anatomic variation of cranial parasympathetic ganglia

    Selma Siéssere

    2008-06-01

    Full Text Available Having broad knowledge of anatomy is essential for practicing dentistry. Certain anatomical structures call for detailed studies due to their anatomical and functional importance. Nevertheless, some structures are difficult to visualize and identify due to their small volume and complicated access. Such is the case of the parasympathetic ganglia located in the cranial part of the autonomic nervous system, which include: the ciliary ganglion (located deeply in the orbit, laterally to the optic nerve, the pterygopalatine ganglion (located in the pterygopalatine fossa, the submandibular ganglion (located laterally to the hyoglossus muscle, below the lingual nerve, and the otic ganglion (located medially to the mandibular nerve, right beneath the oval foramen. The aim of this study was to present these structures in dissected anatomic specimens and perform a comparative analysis regarding location and morphology. The proximity of the ganglia and associated nerves were also analyzed, as well as the number and volume of fibers connected to them. Human heads were dissected by planes, partially removing the adjacent structures to the point we could reach the parasympathetic ganglia. With this study, we concluded that there was no significant variation regarding the location of the studied ganglia. Morphologically, our observations concur with previous classical descriptions of the parasympathetic ganglia, but we observed variations regarding the proximity of the otic ganglion to the mandibular nerve. We also observed that there were variations regarding the number and volume of fiber bundles connected to the submandibular, otic, and pterygopalatine ganglia.

  19. Deviation of landmarks in accordance with methods of establishing reference planes in three-dimensional facial CT evaluation

    Yoon, Kaeng Won; Yoon, Suk Ja; Kang, Byung Cheol; Kook, Min Suk; Lee, Jae Seo [School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of); Kim, Young Hee [Dept. of Oral and Maxillofacial Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Palomo, Juan Martin [Dept. of Orthodontics, School of Dental Medicine, Case Western Reserve University, Cleveland (Korea, Republic of)

    2014-09-15

    This study aimed to investigate the deviation of landmarks from horizontal or midsagittal reference planes according to the methods of establishing reference planes. Computed tomography (CT) scans of 18 patients who received orthodontic and orthognathic surgical treatment were reviewed. Each CT scan was reconstructed by three methods for establishing three orthogonal reference planes (namely, the horizontal, midsagittal, and coronal reference planes). The horizontal (bilateral porions and bilateral orbitales) and midsagittal (crista galli, nasion, prechiasmatic point, opisthion, and anterior nasal spine) landmarks were identified on each CT scan. Vertical deviation of the horizontal landmarks and horizontal deviation of the midsagittal landmarks were measured. The porion and orbitale, which were not involved in establishing the horizontal reference plane, were found to deviate vertically from the horizontal reference plane in the three methods. The midsagittal landmarks, which were not used for the midsagittal reference plane, deviated horizontally from the midsagittal reference plane in the three methods. In a three-dimensional facial analysis, the vertical and horizontal deviations of the landmarks from the horizontal and midsagittal reference planes could vary depending on the methods of establishing reference planes.

  20. Computer tomographic imaging and anatomic correlation of the human brain: A comparative atlas of thin CT-scan sections and correlated neuro-anatomic preparations

    It is of the greatest importance to the radiologist, the neurologist and the neurosurgeon to be able to localize topographically a pathological brain process on the CT scan as precisely as possible. For that purpose, the identification of as many anatomical structures as possible on the CT scan image are necessary and indispensable. In this atlas a great number of detailed anatomical data on frontal horizontal CT scan sections, each being only 2 mm thick, are indicated, e.g. the cortical gyri, the basal ganglia, details of the white matter, extracranial muscles and blood vessels, parts of the base and the vault of the skull, etc. The very precise topographical description of the numerous CT scan images was realized by the author by confrontation of these images with the corresponding anatomical sections of the same brain specimen, performed by an original technique

  1. Anatomical description and clinical significance of unilateral triheaded sternocleidomastoid muscle

    Preeti Goswami

    2014-06-01

    Full Text Available Objective of this report is to observe and report unusual pattern of origin of sternal and clavicular heads of Sternocleidomastoid (SCM. An embryological insight into the possible causes for present anomaly is elucidated. The neck region of an adult male cadaver during gross anatomy teaching program. An abnormal Sternocleidomastoid (SCM was observed while dissecting the neck region of an adult. Additional clavicular head of SCM muscle were found on the right side. The accessory clavicular head coursed deep to the sternal head whereas the some fibres of main clavicular head joined the accessory belly and together they fused with the main sternal head of SCM. There was another slip arising from sternal head and merge with deep cervical fascia near base of mandible. The topographical anatomy of SCM is extremely important, particularly because it serves as a useful surgical landmark and its relation to crucial neuro-vascular structures of the neck. The usage of SCM in reconstruction operations for covering defects is discussed. A detailed knowledge of the anatomy of SCM proves vital for radiological studies of the neck. [Int J Res Med Sci 2014; 2(3.000: 1161-1164

  2. Anatomical versus Non-Anatomical Single Bundle Anterior Cruciate Ligament Reconstruction: A Cadaveric Study of Comparison of Knee Stability

    Lim, Hong-Chul; Yoon, Yong-Cheol; Wang, Joon-Ho; Bae, Ji-Hoon

    2012-01-01

    Background The purpose of this study was to compare the initial stability of anatomical and non-anatomical single bundle anterior cruciate ligament (ACL) reconstruction and to determine which would better restore intact knee kinematics. Our hypothesis was that the initial stability of anatomical single bundle ACL reconstruction would be superior to that of non-anatomical single bundle ACL reconstruction. Methods Anterior tibial translation (ATT) and internal rotation of the tibia were measure...

  3. Integration, Disintegration, and Self-Similarity: Characterizing the Scales of Shape Variation in Landmark Data

    Bookstein, Fred L.

    2015-01-01

    The biologist examining samples of multicellular organisms in anatomical detail must already have an intuitive concept of morphological integration. But quantifying that intuition has always been fraught with difficulties and paradoxes, especially for the anatomically labelled Cartesian coordinate data that drive today’s toolkits of geometric morphometrics. Covariance analyses of interpoint distances, such as the Olson–Miller factor approach of the 1950’s, cannot validly be extended to handle...

  4. Anatomical relation between anterior ethmoidal sinus and lacrimal sac fossa on high resolution CT

    To evaluate the anatomical relation between anterior ethmoidal sinus and the lacrimal sac fossa, and thus help prevent complications during dacryocystorhinostomy. Fifty three people without previous history of trauma, surgery, or paranasal sinus disease were randomly selected, and the 106 lacrimal sac fossas of these subjects were evaluated by high resolution CT. A series of three 2-mm thick axial sections at least 2mm from the inferior orbital wall were obtained. The bony landmarks of the lacrimal sac fossa were established and the location of the most anterior ethmoid sinus was classified as one of three types. In type 1, no sinuses were anterior to the posterior lacrimal crest. While in type 2, sinuses extended anterior to this crest but remained behind the suture at the anterior edge of the lacrimal bone. In type 3, sinuses extended into the frontal process of the maxilla, anterior to the lacrimal bone suture. In addition, the category of both orbits of the same patient was compared. Among the 106 orbits examined, only seven (6.6%) were classified as type 1, with no ethmoid air cells postioned under the lacrimal sac fossa. Seventy six (71.7%) qualified as type 2, while the remaining 23 (21.7%) were type 3, demonstration anterior ethmoid air cells within the nasal process of the maxilla. The position of the air cells was symmetric in 41 of the 53 subjects (77.4%) and asymmetric in 12 (22.6%). In cases involving surgery of the lacrimal sac fossa, such as dacryocystorhinostomy, a knowledge of the consistent anatomic relationship between the anterior ethmoidal sinus and the lacrimal sac fossa is invaluable

  5. [Dyspraxia: landmarks].

    Mazeau, M

    2010-03-01

    Despite its frequency, little is known about dyspraxia. Dyspraxia, which represents disorders in development and learning movements, within the context of a deficiency in the management of spatial information (in children whose verbal intelligence is spared), is often a severe handicap at school and in social life. Dyspraxia must be distinguished from "common" difficulties of unmotivated children at school, with which it is often confused. Hence, the diagnosis must correspond to rigorous methodology. And one should avoid proposing endless training for the deficient action (writing, getting dressed...); indeed such strategies only lead to short-term 'pseudo' progress, without any long term efficacy on the educational success of these intelligent children. To the contrary, the child should be rapidly oriented in two therapeutic directions: (1) a battle between the "double-task" effect stemming from the graphical and spatial difficulties; (2) the use of palliatives (including computing). In conditions of early diagnosis (at 4-8/9 years of age) and well-coordinated management with the school, the prognosis would be excellent in terms of schooling, choice of a profession and social insertion. If not, or if (as is the case in almost a third of cases) dyspraxia is not isolated (associated with dyslexia, hyperactivity, attentional deficit and psychotic traits), the child should be oriented towards a specialised classroom and care. PMID:19942418

  6. An anatomical study of the parasacral block using magnetic resonance imaging of healthy volunteers.

    O'Connor, Maeve

    2012-01-31

    BACKGROUND: The parasacral approach to sciatic blockade is reported to be easy to learn and perform, with a high success rate and few complications. METHODS: Using magnetic resonance imaging, we evaluated the accuracy of a simulated needle (perpendicular to skin) in contacting the sacral plexus with this approach in 10 volunteers. Intrapelvic structures encountered during the simulated parasacral blocks were also recorded. RESULTS: The sacral plexus was contacted by the simulated needle in 4 of the 10 volunteers, and the sciatic nerve itself in one volunteer. The plexus was accurately located adjacent to a variety of visceral structures, including small bowel, blood vessels, and ovary. In the remaining five volunteers (in whom the plexus was not contacted on first needle pass), small bowel, rectum, blood vessels, seminal vesicles, and bony structures were encountered. Historically, when plexus is not encountered, readjustment of the needle insertion point more caudally has been recommended. We found that such an adjustment resulted in simulated perforation of intrapelvic organs or the perianal fossa. CONCLUSIONS: These findings question the reliability of the anatomical landmarks of the parasacral block and raise the possibility of frequent visceral puncture using this technique.

  7. PAVA: Physiological and Anatomical Visual Analytics for Mapping of Tissue-Specific Concentration and Time-Course Data

    We describe the development and implementation of a Physiological and Anatomical Visual Analytics tool (PAVA), a web browser-based application, used to visualize experimental/simulated chemical time-course data (dosimetry), epidemiological data and Physiologically-Annotated Data ...

  8. Constitutional and Anatomical Characteristics of Mature Women

    Vladimir NNikolenko; DmitryBNikityuk; SvetlanaVKlochkova; AnastasiaABahmet

    2015-01-01

    Objective To identify the constitutional and anatomical peculiarities of constitution of women of mature age.Methods There was completed comprehensive anthropometric and bio-electrical survey of 651 mature women ( relative norm) living in the Moscow region .Results The quantitative distribution of women by somatotypological affiliation was revealed;anthropometric and body component composition in representatives of different somatotypes were defined .Conclusion Thus, the performed study revealed and quantiely character-ised the distribution of women according to their constitutional types in the studied population of mature age women living in Moscow region under the relative norm conditions .

  9. "Direct DICOM Slice Landmarking" A Novel Research Technique to Quantify Skeletal Changes in Orthognathic Surgery.

    Anas Almukhtar

    Full Text Available The limitations of the current methods of quantifying the surgical movements of facial bones inspired this study. The aim of this study was the assessment of the accuracy and reproducibility of directly landmarking of 3D DICOM images (Digital Imaging and Communications in Medicine to quantify the changes in the jaw bones following surgery. The study was carried out on plastic skull to simulate the surgical movements of the jaw bones. Cone beam CT scans were taken at 3mm, 6mm, and 9mm maxillary advancement; together with a 2mm, 4mm, 6mm and 8mm "down graft" which in total generated 12 different positions of the maxilla for the analysis. The movements of the maxilla were calculated using two methods, the standard approach where distances between surface landmarks on the jaw bones were measured and the novel approach where measurements were taken directly from the internal structures of the corresponding 3D DICOME slices. A one sample t-test showed that there was no statistically significant difference between the two methods of measurements for the y and z directions, however, the x direction showed a significant difference. The mean difference between the two absolute measurements were 0.34±0.20mm, 0.22±0.16mm, 0.18±0.13mm in the y, z and x directions respectively. In conclusion, the direct landmarking of 3D DICOM image slices is a reliable, reproducible and informative method for assessment of the 3D skeletal changes. The method has a clear clinical application which includes the analysis of the jaw movements "orthognathic surgery" for the correction of facial deformities.

  10. Performance Characterization of a Landmark Measurement System for ARRM Terrain Relative Navigation

    Shoemaker, Michael; Wright, Cinnamon; Liounis, Andrew; Getzandanner, Kenneth; Van Eepoel, John; Deweese, Keith

    2016-01-01

    This paper describes the landmark measurement system being developed for terrain relative navigation on NASAs Asteroid Redirect Robotic Mission (ARRM),and the results of a performance characterization study given realistic navigational and model errors. The system is called Retina, and is derived from the stereophotoclinometry methods widely used on other small-body missions. The system is simulated using synthetic imagery of the asteroid surface and discussion is given on various algorithmic design choices. Unlike other missions, ARRMs Retina is the first planned autonomous use of these methods during the close-proximity and descent phase of the mission.

  11. Assistance to planning in deep brain stimulation: data fusion method for locating anatomical targets in MRI.

    Villéger, Alice; Ouchchane, Lemlih; Lemaire, Jean-Jacques; Boire, Jean-Yves

    2006-01-01

    Symptoms of Parkinson's disease can be relieved through deep brain stimulation. This neurosurgical technique relies on high precision positioning of electrodes in specific areas of the basal ganglia and the thalamus. In order to identify these anatomical targets, which are located deep within the brain, we developed a semi-automated method of image analysis, based on data fusion. Information provided by both anatomical magnetic resonance images and expert knowledge is managed in a common possibilistic frame, using a fuzzy logic approach. More specifically, a graph-based virtual atlas modeling theoretical anatomical knowledge is matched to the image data from each patient, through a research algorithm (or strategy) which simultaneously computes an estimation of the location of every structures, thus assisting the neurosurgeon in defining the optimal target. The method was tested on 10 images, with promising results. Location and segmentation results were statistically assessed, opening perspectives for enhancements. PMID:17946793

  12. Anatomic Optical Coherence Tomography of Upper Airways

    Chin Loy, Anthony; Jing, Joseph; Zhang, Jun; Wang, Yong; Elghobashi, Said; Chen, Zhongping; Wong, Brian J. F.

    The upper airway is a complex and intricate system responsible for respiration, phonation, and deglutition. Obstruction of the upper airways afflicts an estimated 12-18 million Americans. Pharyngeal size and shape are important factors in the pathogenesis of airway obstructions. In addition, nocturnal loss in pharyngeal muscular tone combined with high pharyngeal resistance can lead to collapse of the airway and periodic partial or complete upper airway obstruction. Anatomical optical coherence tomography (OCT) has the potential to provide high-speed three-dimensional tomographic images of the airway lumen without the use of ionizing radiation. In this chapter we describe the methods behind endoscopic OCT imaging and processing to generate full three dimensional anatomical models of the human airway which can be used in conjunction with numerical simulation methods to assess areas of airway obstruction. Combining this structural information with flow dynamic simulations, we can better estimate the site and causes of airway obstruction and better select and design surgery for patients with obstructive sleep apnea.

  13. Integration of tomato reproductive developmental landmarks and expression profiles, and the effect of SUN on fruit shape

    Xiao, Han; Radovich, Cheryll; Welty, Nicholas; Hsu, Jason; Li, Dongmei; Meulia, Tea; van der Knaap, Esther

    2009-01-01

    Background Universally accepted landmark stages are necessary to highlight key events in plant reproductive development and to facilitate comparisons among species. Domestication and selection of tomato resulted in many varieties that differ in fruit shape and size. This diversity is useful to unravel underlying molecular and developmental mechanisms that control organ morphology and patterning. The tomato fruit shape gene SUN controls fruit elongation. The most dramatic effect of SUN on fruit shape occurs after pollination and fertilization although a detailed investigation into the timing of the fruit shape change as well as gene expression profiles during critical developmental stages has not been conducted. Results We provide a description of floral and fruit development in a red-fruited closely related wild relative of tomato, Solanum pimpinellifolium accession LA1589. We use established and propose new floral and fruit landmarks to present a framework for tomato developmental studies. In addition, gene expression profiles of three key stages in floral and fruit development are presented, namely floral buds 10 days before anthesis (floral landmark 7), anthesis-stage flowers (floral landmark 10 and fruit landmark 1), and 5 days post anthesis fruit (fruit landmark 3). To demonstrate the utility of the landmarks, we characterize the tomato shape gene SUN in fruit development. SUN controls fruit shape predominantly after fertilization and its effect reaches a maximum at 8 days post-anthesis coinciding with fruit landmark 4 representing the globular embryo stage of seed development. The expression profiles of the NILs that differ at sun show that only 34 genes were differentially expressed and most of them at a less than 2-fold difference. Conclusion The landmarks for flower and fruit development in tomato were outlined and integrated with the effect of SUN on fruit shape. Although we did not identify many genes differentially expressed in the NILs that differ at

  14. Integration of tomato reproductive developmental landmarks and expression profiles, and the effect of SUN on fruit shape

    Li Dongmei

    2009-05-01

    Full Text Available Abstract Background Universally accepted landmark stages are necessary to highlight key events in plant reproductive development and to facilitate comparisons among species. Domestication and selection of tomato resulted in many varieties that differ in fruit shape and size. This diversity is useful to unravel underlying molecular and developmental mechanisms that control organ morphology and patterning. The tomato fruit shape gene SUN controls fruit elongation. The most dramatic effect of SUN on fruit shape occurs after pollination and fertilization although a detailed investigation into the timing of the fruit shape change as well as gene expression profiles during critical developmental stages has not been conducted. Results We provide a description of floral and fruit development in a red-fruited closely related wild relative of tomato, Solanum pimpinellifolium accession LA1589. We use established and propose new floral and fruit landmarks to present a framework for tomato developmental studies. In addition, gene expression profiles of three key stages in floral and fruit development are presented, namely floral buds 10 days before anthesis (floral landmark 7, anthesis-stage flowers (floral landmark 10 and fruit landmark 1, and 5 days post anthesis fruit (fruit landmark 3. To demonstrate the utility of the landmarks, we characterize the tomato shape gene SUN in fruit development. SUN controls fruit shape predominantly after fertilization and its effect reaches a maximum at 8 days post-anthesis coinciding with fruit landmark 4 representing the globular embryo stage of seed development. The expression profiles of the NILs that differ at sun show that only 34 genes were differentially expressed and most of them at a less than 2-fold difference. Conclusion The landmarks for flower and fruit development in tomato were outlined and integrated with the effect of SUN on fruit shape. Although we did not identify many genes differentially expressed in

  15. Electrochemical degradation of electrodeposited Pt particles on mask scratched substrate using a landmark for ex situ scanning electron microscopy

    Pt particles were deposited on a glassy carbon substrate using a landmark by a mask scratch-based Pt electrodeposition method to observe the same Pt particles by ex situ scanning electron microscopy before and after a potential cycling procedure. The potential cycling was conducted in a H2O2-containing 0.5 mol dm-3 H2SO4 solution. As a result, the Pt particle degradations are clearly observed in the solution containing 100 mmol dm-3 H2O2 in the potential range of 0.04-1.44 V vs. RHE; whereas, the degradations become more remarkable at 0.34-1.44 V vs. RHE. To clarify the reason for this potential cycling range-dependence of the Pt particle degradations, the weight change of a Pt electrode during potential cycling in the presence of H2O2 was measured using an electrochemical quartz crystal microbalance. The result suggests that the dissolved Pt is re-deposited on the Pt in ca. 0.01-0.40 V vs. RHE, which well explains the difference of the Pt particle degradations by the potential cyclings between 0.04-1.44 and 0.34-1.44 V vs. RHE.

  16. Gene Expression Data to Mouse Atlas Registration Using a Nonlinear Elasticity Smoother and Landmark Points Constraints

    Lin, Tungyou; Guyader, Carole Le; Dinov, Ivo; Thompson, Paul; Toga, Arthur; Vese, Luminita

    2013-01-01

    This paper proposes a numerical algorithm for image registration using energy minimization and nonlinear elasticity regularization. Application to the registration of gene expression data to a neuroanatomical mouse atlas in two dimensions is shown. We apply a nonlinear elasticity regularization to allow larger and smoother deformations, and further enforce optimality constraints on the landmark points distance for better feature matching. To overcome the difficulty of minimizing the nonlinear elasticity functional due to the nonlinearity in the derivatives of the displacement vector field, we introduce a matrix variable to approximate the Jacobian matrix and solve for the simplified Euler-Lagrange equations. By comparison with image registration using linear regularization, experimental results show that the proposed nonlinear elasticity model also needs fewer numerical corrections such as regridding steps for binary image registration, it renders better ground truth, and produces larger mutual information; most importantly, the landmark points distance and L2 dissimilarity measure between the gene expression data and corresponding mouse atlas are smaller compared with the registration model with biharmonic regularization. PMID:24273381

  17. Management of neovascular Age-related macular degeneration: A review on landmark randomized controlled trials

    Aniruddha Agarwal

    2016-01-01

    Full Text Available In the last decade, a number of prospective clinical trials with carefully designed study protocols have been conducted for the treatment of neovascular age.related macular degeneration (AMD. These landmark clinical trials such as ANCHOR and MARINA and, more recently, the Comparison of AMD Treatment Trials and VIEW studies have revolutionized the management of neovascular AMD. While AMD continues to remain a leading cause of severe visual loss worldwide, advances in pharmacotherapeutics have led to substantial improvements in the outcome of these patients. The introduction of anti.vascular endothelial growth factor agents has resulted in improvement of visual outcomes and has had a positive impact on the quality of life among elderly population. While the contemporary management of neovascular AMD has been successful in tremendously reducing the visual morbidity, the financial burden of therapy has increased exponentially. To overcome these challenges, newer pharmacologic agents are evaluated for their efficacy and safety in AMD. Ground.breaking advances in bench to bedside research have led to discovery of new pathways that appear to be viable targets for preventing visual loss in AMD. In this review, study designs and results of landmark clinical trials in AMD from the past decade have been summarized.

  18. Visual navigation of the UAVs on the basis of 3D natural landmarks

    Karpenko, Simon; Konovalenko, Ivan; Miller, Alexander; Miller, Boris; Nikolaev, Dmitry

    2015-12-01

    This work considers the tracking of the UAV (unmanned aviation vehicle) on the basis of onboard observations of natural landmarks including azimuth and elevation angles. It is assumed that UAV's cameras are able to capture the angular position of reference points and to measure the angles of the sight line. Such measurements involve the real position of UAV in implicit form, and therefore some of nonlinear filters such as Extended Kalman filter (EKF) or others must be used in order to implement these measurements for UAV control. Recently it was shown that modified pseudomeasurement method may be used to control UAV on the basis of the observation of reference points assigned along the UAV path in advance. However, the use of such set of points needs the cumbersome recognition procedure with the huge volume of on-board memory. The natural landmarks serving as such reference points which may be determined on-line can significantly reduce the on-board memory and the computational difficulties. The principal difference of this work is the usage of the 3D reference points coordinates which permits to determine the position of the UAV more precisely and thereby to guide along the path with higher accuracy which is extremely important for successful performance of the autonomous missions. The article suggests the new RANSAC for ISOMETRY algorithm and the use of recently developed estimation and control algorithms for tracking of given reference path under external perturbation and noised angular measurements.

  19. Nomina anatomica. Anatomic terminology and the old French terminology.

    Chiapas-Gasca, Karla; Passos, Luiz Fernando De Souza; Euzébio Ribeiro, Sandra Lúcia; Villaseñor-Ovies, Pablo

    A surprising finding in our seminars in Latin America and Spain was that approximately half of the participants continued to use the old French anatomical nomenclature. The substance of this paper is a table in which we compare the anatomical names for the items reviewed in our seminar, in a Spanish version of the old French nomenclature and in the Spanish, Portuguese, and English versions of the currently employed anatomical terms. PMID:23228528

  20. Normal anatomical measurements in cervical computerized tomography

    Radiodiagnostically relevant normal values and variations for measurements of the cervical region, the arithmetical average and the standard deviation were determined from adequate computer tomograms on 60 healthy women and men, aged 20 to 83 years. The sagittal diameter of the prevertebral soft tissue and the lumina of the upper respiratory tract were evaluated at exactly defined levels between the hyoid bone and the incisura jugularis sterni. - The thickness of the aryepiglottic folds, the maximal sagittal and transverse diameters of the thyroid gland and the calibre of the great cervical vessels were defined. - To assess information about laryngeal function in computerized tomography, measurements of distances between the cervical spine and anatomical fixed points of the larynx and hypopharynx were made as well as of the degree of vocal cord movement during normal respiration and phonation. (orig.)

  1. [Antique anatomical collections for contemporary museums].

    Nesi, Gabriella; Santi, Raffaella

    2013-01-01

    Anatomy and Pathology Museum collections display a great biological value and offer unique samples for research purposes. Pathological specimens may be investigated by means of modern radiological and molecular biology techniques in order to provide the etiological background of disease, with relevance to present-day knowledge. Meanwhile, historical resources provide epidemiologic data regarding the socio-economic conditions of the resident populations, the more frequently encountered illnesses and dietary habits. These multidisciplinary approaches lead to more accurate diagnoses also allowing new strategies in cataloguing and musealization of anatomical specimens. Further, once these data are gathered, they may constitute the basis of riedited Museum catalogues feasible to be digitalized and displayed via the Web. PMID:25807710

  2. Normal anatomical measurements in cervical computerized tomography

    Zaunbauer, W.; Daepp, S.; Haertel, M.

    1985-11-01

    Radiodiagnostically relevant normal values and variations for measurements of the cervical region, the arithmetical average and the standard deviation were determined from adequate computer tomograms on 60 healthy women and men, aged 20 to 83 years. The sagittal diameter of the prevertebral soft tissue and the lumina of the upper respiratory tract were evaluated at exactly defined levels between the hyoid bone and the incisura jugularis sterni. - The thickness of the aryepiglottic folds, the maximal sagittal and transverse diameters of the thyroid gland and the calibre of the great cervical vessels were defined. - To assess information about laryngeal function in computerized tomography, measurements of distances between the cervical spine and anatomical fixed points of the larynx and hypopharynx were made as well as of the degree of vocal cord movement during normal respiration and phonation.

  3. Anatomic correlations in radiogallium imaging of the peritoneum and retroperitoneum

    Radiogallium (67Ga) imaging of the abdomen and pelvis has been useful not only in detecting inflammations in these regions, but in pointing out their precise anatomic localization. Once the anatomic site is determined, it is often possible to infer the source of origin of the problem (such as ruptured viscus or pancreatitis). Interpretation of the images depends on recognition of patterns that define known anatomic boundaries such as the transverse mesocolon, root of the small mesentery, perirenal space, and pararenal space, or else show diffuse peritoneal uptake. The anatomic patterns may have continued usefulness in future studies, such as when radiolabeled leukocytes are employed to localize inflammations

  4. MRI anatomical variants of mammillary bodies.

    Tagliamonte, Micaela; Sestieri, Carlo; Romani, Gian Luca; Gallucci, Massimo; Caulo, Massimo

    2015-01-01

    The mammillary bodies (MBs) are classically defined as a pair of small round structures located on the undersurface of the diencephalon. The systematic observation of MR brain images of patients with neurological diseases, but also of healthy subjects enrolled in research protocols, reveals, however, a greater anatomical variability. The aim of the present study was to define the spectrum of such variability using spatial normalized 3D TFE T1-weighted MR images in a group of 151 healthy right-handed young subjects (78 females, age range 16-39 years). The MBs were identified on reformatted coronal and axial images and classified according to morphological, positional and numerical criteria. On the basis of coronal images, MBs were first divided into symmetrical (86.1 %) and asymmetrical (13.9 %), depending on their respective height. Symmetrical MBs were further subdivided into three variants [type A (2.7 %), B (76.2 %), C (7.3 %)] according to the depth of the intermammillary sulcus. Two morphological variants were defined on axial images, depending on whether the MBs were circular (63.6 %) or elliptic (36.4 %). This latter group was further divided in two subgroups, depending on whether the MBs were parallel (21.9 %) or convergent (14.6 %). Finally, two subjects (1.3 %) presented a supernumeral MB. The transverse size of the third ventricle was greater in the type A compared to the type B and C groups. Gender did not significantly affect the frequency of MBs variants, except for the three symmetrical subgroups in which the variants A and C were more frequent in males than in females. These findings suggest the presence of an anatomical variability of the MBs, in contrast to their classical definition. Therefore, atypical presentation of MBs can be the expression of this variability rather than a marker of neurological disorders (i.e. cerebral malformation, mesial temporal sclerosis, Wernicke-Korsakoff syndrome). PMID:24072163

  5. Comparison of Image Registration Based Measures of Regional Lung Ventilation from Dynamic Spiral CT with Xe-CT

    Ding, Kai; Fuld, Matthew K; Du, Kaifang; Christensen, Gary E; Hoffman, Eric A; Reinhardt, Joseph M

    2012-01-01

    Purpose: Regional lung volume change as a function of lung inflation serves as an index of parenchymal and airway status as well as an index of regional ventilation and can be used to detect pathologic changes over time. In this article, we propose a new regional measure of lung mechanics --- the specific air volume change by corrected Jacobian. Methods: 4DCT and Xe-CT data sets from four adult sheep are used in this study. Nonlinear, 3D image registration is applied to register an image acquired near end inspiration to an image acquired near end expiration. Approximately 200 annotated anatomical points are used as landmarks to evaluate registration accuracy. Three different registration-based measures of regional lung mechanics are derived and compared: the specific air volume change calculated from the Jacobian (SAJ); the specific air volume change calculated by the corrected Jacobian (SACJ); and the specific air volume change by intensity change (SAI). Results: After registration, the mean registration err...

  6. A "Second Life" for Gross Anatomy: Applications for Multiuser Virtual Environments in Teaching the Anatomical Sciences

    Richardson, April; Hazzard, Matthew; Challman, Sandra D.; Morgenstein, Aaron M.; Brueckner, Jennifer K.

    2011-01-01

    This article describes the emerging role of educational multiuser virtual environments, specifically Second Life[TM], in anatomical sciences education. Virtual worlds promote inquiry-based learning and conceptual understanding, potentially making them applicable for teaching and learning gross anatomy. A short introduction to Second Life as an…

  7. Internal fixation of the unstable pelvic fracture based on the anatomic features of the pelvis%骨盆的形态特点与不稳定型骨折内固定治疗评价

    翁阳华; 吴显奎; 彭扬国; 欧耀芬

    2011-01-01

    目的 探讨根据骨盆的形态特点选择不同的内固定手术治疗不稳定型骨盆骨折的临床应用价值。方法65例不稳定型骨盆骨折,31例Tile B型骨折经前入路,将耻骨联合或耻骨支复位用重建钢板固定,其中8例合并髂骨骨折经髂窝入路将之复位用重建钢板固定;34例Tile C型骨折的前环损伤均采用与Tile B型骨盆骨折相同的方法处理,后环损伤的固定方法:17例骶骨骨折或骶髂关节脱位之中,复位后在透视引导下从后方经皮骶髂螺钉固定11例,经髂骨的螺栓固定4例,经后路在双侧髂骨后嵴之间用张力带钢板固定2例;9例骶髂关节骨折-脱位之中,经皮骶髂螺钉固定6例,钢板固定3例;8例合并髋臼骨折行重建钢板内固定。结果通过对术后骨盆X线测量骨折分离移位的最大距离,根据Matta评分标准:小于4 mm为优,占86.1%(56例);4~10mm为良,占7.7%(5例);10~20 mm为可,占6.2%(4例);大于20 mm为差(0例)。本组骨盆X线测量结果总优良率为93.8%。结论不稳定型骨盆骨折应在血流动力学稳定时尽早根据骨折的类型及骨盆的解剖形态特点选择合理的内固定手术方案。%Objective To explore clinical efficiency of different surgical internal fixations on treating the unstable pelvic fracture according to the anatomic features of the pelvis. Methods 65 cases suffering from the unstable pelvic fractures, were included in this study. Anterior approach, with the replacement and plate fixation of symphysis pubis or ramus of pubis, was performed for 31 cases of Tile B type fracture. 8 cases combined with ilium fracture among them were replaced and fixed through iliac fossa approach. As well, anterior approach also was used for fixing damaged anterior girdle of 34 cases of Tile C type fracture. However, the damaged posterior girdles were treated with the replacement and the posterior sacroiliac screw fixation

  8. Observations of the origin and insertion of the plantar aponeurosis based on anatomic and sonographic analysis%跖腱膜起点的解剖及超声影像学研究

    程迅生; 章仁品; 罗福成; 张勇

    2009-01-01

    Objective To identify the exact origin and insertion of plantar aponeurosis and the anatomic relationship of calcaneal spur to plantar aponeurosis. Methods Fourteen specimen of feet were dissected and radiographed. Three fetus feet were observed histologically. Sonographic evaluation was carried out on 20 normal adults and 52 patients with plantar fasciitis. Results (1) Anatomic observation found that plantar aponeurosis was located under the medial process of caleaneus but not attached to it, and proximally attached to the plantar aspect of calcaneal tuborosity. The insertion (origin) of plantar aponeurosis was not a point but a face. Posteriorly the plantar aponeurosis and fascia of Archlles heel were fused or transmigrated together,entirely covered and attached very coherently to the plantar and posterior aspect of calcaneal tuborosity. (2) Histological observation of heel of fetuses found plantar aponeurosis and fascia of Arehlles heel were eosinophil band-like structure. Both continued at the plantar and posterior aspect of calcaneus and attached closely to bone at this area. There were no significant demarcation between them. (3) Sonographic evaluation:normal plantar aponeurosis showed a thin band-like echo, its orgin attached to entire plantar aspect of calcaneal tuberosity and continued with fascia coming posteriorly from Archlles heel. No distinct boundary existed between these two fascias. When plantar fasciitis occurred, the orgin of plantar aponeurosis thickened significantly,this phenomenon could be detected in wholly plantar aspect of calcaneal tuberrosity. The heel spur didn't located within plantar aponeurosis. Conclusions Plantar aponeurosis orginates from entire plantar aspect of cancaneal tuberosity. Heel spur oeeures in the orgin of the intrinsic musculature, such as flexor digitorum brevis,and doesn't locate within plantar aponeurosis.%目的 研究跖腱膜起点的确切部位及其与跟骨骨刺的关系.方法 对14只足标

  9. Foundations of Intonational Meaning: Anatomical and Physiological Factors.

    Gussenhoven, Carlos

    2016-04-01

    Like non-verbal communication, paralinguistic communication is rooted in anatomical and physiological factors. Paralinguistic form-meaning relations arise from the way these affect speech production, with some fine-tuning by the cultural and linguistic context. The effects have been classified as "biological codes," following the terminological lead of John Ohala's Frequency Code. Intonational morphemes, though arguably non-arbitrary in principle, are in fact heavily biased toward these paralinguistic meanings. Paralinguistic and linguistic meanings for four biological codes are illustrated. In addition to the Frequency Code, the Effort Code, and the Respiratory Code, the Sirenic Code is introduced here, which is based on the use of whispery phonation, widely seen as being responsible for the signaling and perception of feminine attractiveness and sometimes used to express interrogativity in language. In the context of the evolution of language, the relations between physiological conditions and the resulting paralinguistic and linguistic meanings will need to be clarified. PMID:27016315

  10. A method of basal forebrain anatomical standardization for functional image analysis.

    Buchsbaum, M S; Fallon, J H; Wei, T C; Guich, S; Spiegel-Cohen, J; Hamilton, M; Tang, C

    1998-12-14

    Functional as well as structural assessment of the basal forebrain has mostly focused on the dorsal caudate and putamen in axial slices where they are easily outlined or their centers located with stereotaxic methods. The more ventral extent of the basal forebrain, where the irregular form and indistinct boundaries of the nucleus accumbens and substantia innominata are difficult to trace and where the brain's ventral surface may contribute partial volume artifacts to measurement, has been less studied. We present a method based on coronal sections, landmarks placed on clearly visible anchor points, and the computational technique of thin-plate spline warping which allows the alignment of groups of individuals to common coordinates for pixel-by-pixel statistical mapping. The reliability of the landmarks across independent raters yields a median absolute difference of 1.3-1.6 mm. The validity of the method is confirmed by variance maps which reveal significant decreases in variance over spindle and bounding box alignment. PMID:10710168

  11. Corrective surgery for canine patellar luxation in 75 cases (107 limbs: landmark for block recession

    Mitsuhiro Isaka

    2014-05-01

    Full Text Available Canine medial patellar luxation (MPL is a very common orthopedic disease in small animals. Because the pathophysiology of this disease involves various pathways, the surgical techniques and results vary according to the veterinarian. Further, the landmark for block recession is not completely clear. We retrospectively evaluated 75 dogs (107 limbs with MPL in whom our landmark for block recession was used from July 2008 to May 2013. Information regarding the breed, age, sex, body weight, body condition score (BCS, lateral vs bilateral, pre-operative grading, surgical techniques, removal of implants, concomitance with anterior cruciate ligament (ACL rupture, re-luxation, re-operation, and rehabilitation was obtained from the medical records. The breeds were as follows: Chihuahua (n=23, Pomeranian (n=12, Yorkshire Terrier (n=9, and so on. The study group consisted of 33 males (castrated n=13 and 42 females (spayed n=21. The median age was 53.3±35.9 months (32-146 months; 13 cases were less than 12 months of age (17.3%. The pre-surgical BCSs were as follows: 1 (n=0, 2 (n=20, 3 (n=24, 4 (n=24 and 5 (n=7. The body weight was 4.51±3.48 kg (1.34-23.0 kg; 71 cases (94.7% were less than 10 kg. The MPL grades (each limb were G1 (n=1, G2 (n=18, G3 (n=78, and G4 (n=10; 32 cases were bilateral and 43 cases were unilateral (right n=27; left n=16. The specific surgical procedure (distal femoral osteotomy was 3 stifles in Chihuahuas. Concurrent with ACL rupture was 16/107 stifles (15.0% corrected with the over-the-top method or the extracapsular method in Papillons (5/6, Chihuahuas (5/23, and so on. The occurrences of re-luxation and re-operation were 3 out of 107 stifles (2.8% and 0%, respectively. In this retrospective study, we present a potentially good surgical landmark for block recession of MPL in dogs.

  12. Curricular response to increase recall and transfer of anatomical knowledge into the obstetrics/gynecology clerkship.

    Jurjus, Rosalyn A; Brown, Kirsten; Goldman, Ellen; Galoosian, Artin; Butera, Gisela; Krapf, Jill M

    2016-07-01

    Deficits in retention of anatomy knowledge from the preclinical years to clinical application on the wards have been well documented in the medical education literature. We developed and evaluated a web and laboratory-based curriculum to address deficits in anatomy knowledge retention and to increase anatomy knowledge recall through repetition and application of clinical concepts during the obstetrics and gynecology (Ob/Gyn) core clinical clerkship. Using principles of adult learning and instructional design, a curriculum was designed consisting of (1) interactive, case-based e-modules reviewing clinically relevant anatomical topics and (2) a hands-on laboratory session reinforcing the content of the e-modules, with the practice of clinical techniques using anatomical cadaveric dissections. The curriculum's effectiveness was evaluated by using multiple choice testing and comparing baseline and final test scores. For questions testing content directly covered in this curriculum, mean final scores increased by 14.3% (P improvement, P = 0.002). A curriculum with web-based preparatory material and a hands-on gross anatomy laboratory session effectively addresses deficits in anatomy retention and improves anatomical knowledge recall for medical students on a clinical clerkship. In the future, the authors plan to conduct a multicenter study to further evaluate the ability of this curriculum to improve clinically relevant anatomical knowledge. Anat Sci Educ 9: 337-343. © 2015 American Association of Anatomists. PMID:26588426

  13. Landmarks in particle physics at Brookhaven National Laboratory: Brookhaven Lecture Series, Number 238

    Robert Adair's lecture on Landmarks in Particle Physics at Brookhaven National Laboratory (BNL) is a commemoration of the 40th Anniversary of Brookhaven National Laboratory. Adair describes ten researches in elementary particle physics at Brookhaven that had a revolutionary impact on the understanding of elementary particles. Two of the discoveries were made in 1952 and 1956 at the Cosmotron, BNL's first proton accelerator. Four were made in 1962 and 1964 at the Alternating Gradient Synchrotron, the Cosmotron's replacement. Two other discoveries in 1954 and 1956 were theoretical, and strong focusing (1952) is the only technical discovery. One discovery (1958) happened in an old barrack. Four of the discoveries were awarded the Nobel prize in Physics. Adair believes that all of the discoveries are worthy of the Nobel prize. 14 figs

  14. Effects of Spatial Ability, Gender Differences, and Pictorial Training on Children Using 2-D and 3-D Environments to Recall Landmark Locations from Memory

    Kopcha, Theodore J.; Otumfuor, Beryl A.; Wang, Lu

    2015-01-01

    This study examines the effects of spatial ability, gender differences, and pictorial training on fourth grade students' ability to recall landmark locations from memory. Ninety-six students used Google Earth over a 3-week period to locate landmarks (3-D) and mark their location on a 2-D topographical map. Analysis of covariance on posttest scores…

  15. An Investigation of Anatomical Competence in Junior Medical Doctors

    Vorstenbosch, Marc A. T. M.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2016-01-01

    Because of a decrease of the time available for anatomy education, decisions need to be made to reduce the relevant content of the anatomy curriculum. Several expert consensus initiatives resulted in lists of structures, lacking analysis of anatomical competence. This study aims to explore the use of anatomical knowledge by medical doctors in an…

  16. Volumetric Image Guidance Using Carina vs Spine as Registration Landmarks for Conventionally Fractionated Lung Radiotherapy

    Lavoie, Caroline; Higgins, Jane; Bissonnette, Jean-Pierre [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, M5G 2M9 (Canada); Le, Lisa W. [Department of Biostatistics, Princess Margaret Hospital, Toronto, Ontario, M5G 2M9 (Canada); Sun, Alexander; Brade, Anthony; Hope, Andrew; Cho, John [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, M5G 2M9 (Canada); Bezjak, Andrea, E-mail: andrea.bezjak@rmp.uhn.on.ca [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, M5G 2M9 (Canada)

    2012-12-01

    Purpose: To compare the relative accuracy of 2 image guided radiation therapy methods using carina vs spine as landmarks and then to identify which landmark is superior relative to tumor coverage. Methods and Materials: For 98 lung patients, 2596 daily image-guidance cone-beam computed tomography scans were analyzed. Tattoos were used for initial patient alignment; then, spine and carina registrations were performed independently. A separate analysis assessed the adequacy of gross tumor volume, internal target volume, and planning target volume coverage on cone-beam computed tomography using the initial, middle, and final fractions of radiation therapy. Coverage was recorded for primary tumor (T), nodes (N), and combined target (T+N). Three scenarios were compared: tattoos alignment, spine registration, and carina registration. Results: Spine and carina registrations identified setup errors {>=}5 mm in 35% and 46% of fractions, respectively. The mean vector difference between spine and carina matching had a magnitude of 3.3 mm. Spine and carina improved combined target coverage, compared with tattoos, in 50% and 34% (spine) to 54% and 46% (carina) of the first and final fractions, respectively. Carina matching showed greater combined target coverage in 17% and 23% of fractions for the first and final fractions, respectively; with spine matching, this was only observed in 4% (first) and 6% (final) of fractions. Carina matching provided superior nodes coverage at the end of radiation compared with spine matching (P=.0006), without compromising primary tumor coverage. Conclusion: Frequent patient setup errors occur in locally advanced lung cancer patients. Spine and carina registrations improved combined target coverage throughout the treatment course, but carina matching provided superior combined target coverage.

  17. Selection of Laryngoscope Blade Size by Using Facial Landmark for Pediatric Intubation

    S Soltani Mohammadi

    2006-08-01

    Full Text Available Background: The study evaluates whether facial landmarks can be used to estimate an appropriate laryngoscope blade length for oral endotracheal intubation in children. We tested the hypothesis that the laryngoscope blade measuring 10 mm or less distal or proximal to the angle of the mandible (when the flat portion of the blade follows the facial contour from the upper incisor teeth to the angle of the mandible will demonstrate greater success and ease of oral tracheal intubation. Methods: In an observational and prospective study, 60 children 8 years old or younger were undergoing direct laryngoscopy for oral endotracheal intubation in the operating room, were enrolled in the study. Intubation at first time considered successful and intubation with more than one attempt considered unsuccessful. Ease and success of oral tracheal intubation were compared with distance measurements from the angle of the mandible to the tip of the laryngoscope blade. Blade lengths considered too short (blade lengths >10 mm proximal to the angle of the mandible and too long extending longer than 10 mm past the angle of the mandible. Finding: Only 66% of the intubations using the shorter blade were performed on the first attempt as compared with 88.3% of the intubations using the recommended length or 81.2 % of the intubations using blades extending longer than 10 mm past the angle of the mandible (Chi-square, p=0.02. Fisher exact test showed that recommended blade was more successful than longer blade (p=0.048. Conclusion: Our findings suggest that facial landmarks seem to be excellent clinical criteria for laryngoscope blade length selection for pediatric intubations. When the blade is placed at the upper midline incisor teeth and the tip is located within 1 cm proximal or distal to the angle of the mandible, oral tracheal intubations can be accomplished on the first attempt.

  18. Volumetric Image Guidance Using Carina vs Spine as Registration Landmarks for Conventionally Fractionated Lung Radiotherapy

    Purpose: To compare the relative accuracy of 2 image guided radiation therapy methods using carina vs spine as landmarks and then to identify which landmark is superior relative to tumor coverage. Methods and Materials: For 98 lung patients, 2596 daily image-guidance cone-beam computed tomography scans were analyzed. Tattoos were used for initial patient alignment; then, spine and carina registrations were performed independently. A separate analysis assessed the adequacy of gross tumor volume, internal target volume, and planning target volume coverage on cone-beam computed tomography using the initial, middle, and final fractions of radiation therapy. Coverage was recorded for primary tumor (T), nodes (N), and combined target (T+N). Three scenarios were compared: tattoos alignment, spine registration, and carina registration. Results: Spine and carina registrations identified setup errors ≥5 mm in 35% and 46% of fractions, respectively. The mean vector difference between spine and carina matching had a magnitude of 3.3 mm. Spine and carina improved combined target coverage, compared with tattoos, in 50% and 34% (spine) to 54% and 46% (carina) of the first and final fractions, respectively. Carina matching showed greater combined target coverage in 17% and 23% of fractions for the first and final fractions, respectively; with spine matching, this was only observed in 4% (first) and 6% (final) of fractions. Carina matching provided superior nodes coverage at the end of radiation compared with spine matching (P=.0006), without compromising primary tumor coverage. Conclusion: Frequent patient setup errors occur in locally advanced lung cancer patients. Spine and carina registrations improved combined target coverage throughout the treatment course, but carina matching provided superior combined target coverage.

  19. [The alteration of Japanese anatomical terminology in the early Showa period and the Japanese language reform campaign].

    Sawai, Tadashi; Sakai, Tatsuo

    2010-03-01

    In the second decade of the Showa period, great changes were made in the Japanese anatomical terms. It has been proposed that the presentation of JNA (Jenaer nomina anatomica) was one of the factors leading to the change. The Japanese language reform campaign, however, played an important role. The party kokugoaigo doumei and its successor kokugo kyokai required concise and unified technical terms. The anatomical nomenclature committee of the Japanese Association of Anatomists worked to satisfy this requirement. The committee consulted with nomenclature committees of other medical associations and took account of their opinions. The anatomical nomenclature committee abandoned the literal translation from Latin to Japanese and shaped a succinct Japanese terminology. Modern Japanese anatomical terms are based on this terminology. PMID:20614732

  20. Design and use of numerical anatomical atlases for radiotherapy

    The main objective of this thesis is to provide radio-oncology specialists with automatic tools for delineating organs at risk of a patient undergoing a radiotherapy treatment of cerebral or head and neck tumors. To achieve this goal, we use an anatomical atlas, i.e. a representative anatomy associated to a clinical image representing it. The registration of this atlas allows us to segment automatically the patient structures and to accelerate this process. Contributions in this method are presented on three axes. First, we want to obtain a registration method which is as independent as possible from the setting of its parameters. This setting, done by the clinician, indeed needs to be minimal while guaranteeing a robust result. We therefore propose registration methods allowing a better control of the obtained transformation, using rejection techniques of inadequate matching or locally affine transformations. The second axis is dedicated to the consideration of structures associated with the presence of the tumor. These structures, not present in the atlas, indeed lead to local errors in the atlas-based segmentation. We therefore propose methods to delineate these structures and take them into account in the registration. Finally, we present the construction of an anatomical atlas of the head and neck region and its evaluation on a database of patients. We show in this part the feasibility of the use of an atlas for this region, as well as a simple method to evaluate the registration methods used to build an atlas. All this research work has been implemented in a commercial software (Imago from DOSIsoft), allowing us to validate our results in clinical conditions. (author)

  1. Anatomical Correlates of Non-Verbal Perception in Dementia Patients

    Lin, Pin-Hsuan; Chen, Hsiu-Hui; Chen, Nai-Ching; Chang, Wen-Neng; Huang, Chi-Wei; Chang, Ya-Ting; Hsu, Shih-Wei; Hsu, Che-Wei; Chang, Chiung-Chih

    2016-01-01

    Purpose: Patients with dementia who have dissociations in verbal and non-verbal sound processing may offer insights into the anatomic basis for highly related auditory modes. Methods: To determine the neuronal networks on non-verbal perception, 16 patients with Alzheimer’s dementia (AD), 15 with behavior variant fronto-temporal dementia (bv-FTD), 14 with semantic dementia (SD) were evaluated and compared with 15 age-matched controls. Neuropsychological and auditory perceptive tasks were included to test the ability to compare pitch changes, scale-violated melody and for naming and associating with environmental sound. The brain 3D T1 images were acquired and voxel-based morphometry (VBM) was used to compare and correlated the volumetric measures with task scores. Results: The SD group scored the lowest among 3 groups in pitch or scale-violated melody tasks. In the environmental sound test, the SD group also showed impairment in naming and also in associating sound with pictures. The AD and bv-FTD groups, compared with the controls, showed no differences in all tests. VBM with task score correlation showed that atrophy in the right supra-marginal and superior temporal gyri was strongly related to deficits in detecting violated scales, while atrophy in the bilateral anterior temporal poles and left medial temporal structures was related to deficits in environmental sound recognition. Conclusions: Auditory perception of pitch, scale-violated melody or environmental sound reflects anatomical degeneration in dementia patients and the processing of non-verbal sounds are mediated by distinct neural circuits.

  2. The teleost anatomy ontology: anatomical representation for the genomics age.

    Dahdul, Wasila M; Lundberg, John G; Midford, Peter E; Balhoff, James P; Lapp, Hilmar; Vision, Todd J; Haendel, Melissa A; Westerfield, Monte; Mabee, Paula M

    2010-07-01

    The rich knowledge of morphological variation among organisms reported in the systematic literature has remained in free-text format, impractical for use in large-scale synthetic phylogenetic work. This noncomputable format has also precluded linkage to the large knowledgebase of genomic, genetic, developmental, and phenotype data in model organism databases. We have undertaken an effort to prototype a curated, ontology-based evolutionary morphology database that maps to these genetic databases (http://kb.phenoscape.org) to facilitate investigation into the mechanistic basis and evolution of phenotypic diversity. Among the first requirements in establishing this database was the development of a multispecies anatomy ontology with the goal of capturing anatomical data in a systematic and computable manner. An ontology is a formal representation of a set of concepts with defined relationships between those concepts. Multispecies anatomy ontologies in particular are an efficient way to represent the diversity of morphological structures in a clade of organisms, but they present challenges in their development relative to single-species anatomy ontologies. Here, we describe the Teleost Anatomy Ontology (TAO), a multispecies anatomy ontology for teleost fishes derived from the Zebrafish Anatomical Ontology (ZFA) for the purpose of annotating varying morphological features across species. To facilitate interoperability with other anatomy ontologies, TAO uses the Common Anatomy Reference Ontology as a template for its upper level nodes, and TAO and ZFA are synchronized, with zebrafish terms specified as subtypes of teleost terms. We found that the details of ontology architecture have ramifications for querying, and we present general challenges in developing a multispecies anatomy ontology, including refinement of definitions, taxon-specific relationships among terms, and representation of taxonomically variable developmental pathways. PMID:20547776

  3. Anatomical imbalance between cortical networks in autism

    Watanabe, Takamitsu; Rees, Geraint

    2016-01-01

    Influential psychological models of autism spectrum disorder (ASD) have proposed that this prevalent developmental disorder results from impairment of global (integrative) information processing and overload of local (sensory) information. However, little neuroanatomical evidence consistent with this account has been reported. Here, we examined relative grey matter volumes (rGMVs) between three cortical networks, how they changed with age, and their relationship with core symptomatology. Using public neuroimaging data of high-functioning ASD males and age-/sex-/IQ-matched controls, we first identified age-associated atypical increases in rGMVs of the regions of two sensory systems (auditory and visual networks), and an age-related aberrant decrease in rGMV of a task-control system (fronto-parietal network, FPN) in ASD children. While the enlarged rGMV of the auditory network in ASD adults was associated with the severity of autistic socio-communicational core symptom, that of the visual network was instead correlated with the severity of restricted and repetitive behaviours in ASD. Notably, the atypically decreased rGMV of FPN predicted both of the two core symptoms. These findings suggest that disproportionate undergrowth of a task-control system (FPN) may be a common anatomical basis for the two ASD core symptoms, and relative overgrowth of the two different sensory systems selectively compounds the distinct symptoms. PMID:27484308

  4. Anatomical imbalance between cortical networks in autism.

    Watanabe, Takamitsu; Rees, Geraint

    2016-01-01

    Influential psychological models of autism spectrum disorder (ASD) have proposed that this prevalent developmental disorder results from impairment of global (integrative) information processing and overload of local (sensory) information. However, little neuroanatomical evidence consistent with this account has been reported. Here, we examined relative grey matter volumes (rGMVs) between three cortical networks, how they changed with age, and their relationship with core symptomatology. Using public neuroimaging data of high-functioning ASD males and age-/sex-/IQ-matched controls, we first identified age-associated atypical increases in rGMVs of the regions of two sensory systems (auditory and visual networks), and an age-related aberrant decrease in rGMV of a task-control system (fronto-parietal network, FPN) in ASD children. While the enlarged rGMV of the auditory network in ASD adults was associated with the severity of autistic socio-communicational core symptom, that of the visual network was instead correlated with the severity of restricted and repetitive behaviours in ASD. Notably, the atypically decreased rGMV of FPN predicted both of the two core symptoms. These findings suggest that disproportionate undergrowth of a task-control system (FPN) may be a common anatomical basis for the two ASD core symptoms, and relative overgrowth of the two different sensory systems selectively compounds the distinct symptoms. PMID:27484308

  5. Anatomical challenges for transcatheter mitral valve intervention.

    DE Backer, Ole; Luk, Ngai H; Søndergaard, Lars

    2016-06-01

    Following the success of transcatheter aortic and pulmonary valve implantation, there is a large interest in transcatheter mitral valve interventions to treat severe mitral regurgitation (MR). With the exception for the MitraClipTM (Abbott, Abbott Park, IL, USA) edge-to-edge leaflet plication system, most of these transcatheter mitral valve interventions are still in their early clinical or preclinical development phase. Challenges arising from the complex anatomy of the mitral valve and the interplay of the mitral apparatus with the left ventricle (LV) have contributed to a more difficult development process and mixed clinical results with these novel technologies. This review aims to discuss the several anatomical aspects and challenges related to transcatheter mitral valve intervention - the relevant anatomy will be reviewed in relation to specific requirements for device design and procedural aspects of transcatheter mitral valve interventions. To date, experience with these novel therapeutic modalities are still limited and resolution of many challenges are pending. Future studies have to evaluate for whom the transcatheter approach is a feasible and preferred treatment and which patients will benefit from either transcatheter mitral valve repair or replacement. Nevertheless, technological developments are anticipated to drive the transcatheter approach forward into a clinically feasible alternative to surgery for selected patients with severe MR. PMID:27028333

  6. Landmark-based model-free 3D face shape reconstruction from video sequences

    Dam, van Chris; Veldhuis, Raymond; Spreeuwers, Luuk; Broemme, A.; Busch, C.

    2013-01-01

    In forensic comparison of facial video data, often only the best quality frontal face frames are selected, and hence potentially useful video data is ignored. To improve 2D facial comparison for law enforcement and forensic investigation, we introduce a model-free 3D shape reconstruction algorithm b

  7. Landmark based morphometric variation in Common dolphin (Delphinus delphis L.,1758)

    Nicolosi, Paola; Loy, Anna

    2010-01-01

    In this study we compare Mediterranean stocks of Delphinus delphis (L., 1758) with other populations of the same species coming from different seas using a geometric morphometrics method. The aim is to define the patterns of geographical variation of Delphinus delphis through a geometric morphometrics analysis of the skulls of 124 individuals from seven marine areas (West and East Pacific Ocean; North-east and South-East Atlantic Ocean, West and East Indian Ocean, Mediterran...

  8. An anatomic gene expression atlas of the adult mouse brain.

    Ng, Lydia; Bernard, Amy; Lau, Chris; Overly, Caroline C; Dong, Hong-Wei; Kuan, Chihchau; Pathak, Sayan; Sunkin, Susan M; Dang, Chinh; Bohland, Jason W; Bokil, Hemant; Mitra, Partha P; Puelles, Luis; Hohmann, John; Anderson, David J; Lein, Ed S; Jones, Allan R; Hawrylycz, Michael

    2009-03-01

    Studying gene expression provides a powerful means of understanding structure-function relationships in the nervous system. The availability of genome-scale in situ hybridization datasets enables new possibilities for understanding brain organization based on gene expression patterns. The Anatomic Gene Expression Atlas (AGEA) is a new relational atlas revealing the genetic architecture of the adult C57Bl/6J mouse brain based on spatial correlations across expression data for thousands of genes in the Allen Brain Atlas (ABA). The AGEA includes three discovery tools for examining neuroanatomical relationships and boundaries: (1) three-dimensional expression-based correlation maps, (2) a hierarchical transcriptome-based parcellation of the brain and (3) a facility to retrieve from the ABA specific genes showing enriched expression in local correlated domains. The utility of this atlas is illustrated by analysis of genetic organization in the thalamus, striatum and cerebral cortex. The AGEA is a publicly accessible online computational tool integrated with the ABA (http://mouse.brain-map.org/agea). PMID:19219037

  9. Neuroanatomy-based matrix-guided trimming protocol for the rat brain.

    Defazio, Rossella; Criado, Ana; Zantedeschi, Valentina; Scanziani, Eugenio

    2015-02-01

    Brain trimming through defined neuroanatomical landmarks is recommended to obtain consistent sections in rat toxicity studies. In this article, we describe a matrix-guided trimming protocol that uses channels to reproduce coronal levels of anatomical landmarks. Both setup phase and validation study were performed on Han Wistar male rats (Crl:WI(Han)), 10-week-old, with bodyweight of 298 ± 29 (SD) g, using a matrix (ASI-Instruments(®), Houston, TX) fitted for brains of rats with 200 to 400 g bodyweight. In the setup phase, we identified eight channels, that is, 6, 8, 10, 12, 14, 16, 19, and 21, matching the recommended landmarks midway to the optic chiasm, frontal pole, optic chiasm, infundibulum, mamillary bodies, midbrain, middle cerebellum, and posterior cerebellum, respectively. In the validation study, we trimmed the immersion-fixed brains of 60 rats using the selected channels to determine how consistently the channels reproduced anatomical landmarks. Percentage of success (i.e., presence of expected targets for each level) ranged from 89 to 100%. Where 100% success was not achieved, it was noted that the shift in brain trimming was toward the caudal pole. In conclusion, we developed and validated a trimming protocol for the rat brain that allow comparable extensiveness, homology, and relevance of coronal sections as the landmark-guided trimming with the advantage of being quickly learned by technicians. PMID:24947989

  10. An unusual intraventricular interthalamic vein: two anatomical case reports.

    Capel, Cyrille; Peltier, Johann; Foulon, Pascal; Page, Cyril; Havet, Eric; Le Gars, Daniel

    2012-12-01

    Neurosurgeons use ventricular veins during an endoscopic third ventriculocisternostomy as landmark to progress in ventricles. In the current literature, there is lack of detailed intraventricular venous anatomy. Majority of those papers treats Monro's foramen venous variations. There are no data of third ventricle venous anatomy and variations in the literature. We reported two cases of unusual interthalamic vein that we need to spare during endoscopy. PMID:22543760

  11. Assessment and Evaluation of Anatomic Variations of Retromolar Pad: A Cross Sectional Study

    Deep, Anchal; Siwach, Amit; Singh, Manas; Bhargava, Akshay; Siwach, Reenu

    2016-01-01

    Introduction The retromolar pad also called piriformis papilla is a mucosal elevation located in the retromolar area covering the retromolar triangle. After molar loss, the bony alveolar process and surrounding soft periodontal tissue remodel, mainly resorb and blend with retromolar pad. It is a key intraoral landmark in prosthodontics. Aim The aim of this in-vitro study was to analyze the various anatomical shapes and sizes of retromolar pad in 150 completely edentulous patients between 55 to 70 years of age group. Materials and Methods The study was conducted on 150 completely edentulous patients. The shapes of retromolar pad on the left and right side were seen and divided into pear, triangular and round shape. The comparison of the mean longitudinal diameter and transverse diameter on the right and left sides was done. The data was evaluated statistically. The chi-square test was used for the comparison between the proportions with the help of standard deviation, t-test was used for comparison between the left and the right side and ANOVA test was used for comparison between the various shapes of the retromolar pads. Results The result showed that there was statistically significant difference among different shapes of retromolar pad and there was significant difference in mean transverse and longitudinal diameter on right and left side, the mean value of the longitudinal diameter on left and right side was 8.81 and 8.69 whereas the mean value of the transverse diameter on left and right side was 6.79 and 6.82 respectively and p-value obtained for both was 0.550 and 0.814 respectively. Conclusion The study conclude that there are three different shapes of retromolar pad among which pear and triangular shaped retomolar pad provides more stability in lower denture because of increase surface area. PMID:27437350

  12. CBCT with specification of imaging dose and CNR by anatomical volume of interest

    Leary, Del, E-mail: dleary@dal.ca [Department of Physics and Atmospheric Science, Dalhousie University, 5820 University Avenue, Halifax, Nova Scotia B3H 1V7 (Canada); Robar, James L., E-mail: james.robar@cdha.nshealth.ca [Department of Radiation Oncology and Department of Physics and Atmospheric Science, Dalhousie University, 5820 University Avenue, Halifax, Nova Scotia B3H 1V7 (Canada)

    2014-01-15

    Purpose: A novel method has been developed for volume of interest (VOI) cone-beam CT (CBCT) imaging using a 2.35 MV/Carbon target linac imaging beam line combined with dynamic multileaf collimator sequences. Methods: The authors demonstrate the concept of acquisition of multiple, separate imaging volumes, where volumes can be either completely separated or nested, and are associated with predetermined imaging dose and contrast-to-noise ratio (CNR) characteristics. Two individual MLC sequences were established in the planning system (Eclipse, Varian Medical) to collimate the beam according to a defined inner VOI (e.g., containing a target volume under image guidance) and an outer VOI (e.g., including surrounding landmarks or organs-at-risk). MLC sequences were interleaved as a function of gantry angle to produce a reconstructed CBCT image with nested VOIs. By controlling the ratio of inner-to-outer ratio of MLC segments (and thus Monitor Units) during acquisition, the relative dose and CNR in the two volumes can be controlled. Inner-to-outer ratios of 2:1 to 6:1 were examined. Results: The concept was explored using an anatomical head phantom to assess image quality. A geometric phantom was used to quantify absolute dose and CNR values for the various sequences. The authors found that the dose in the outer VOI decreased by a functional relationship dependent on the inner-to-outer sequence ratio, while the CNR varied by the square root of dose, as expected. Conclusions: In this study the authors demonstrate flexibility in VOI CBCT by tailoring the imaging dose and CNR distribution in separate volumes within the patient anatomy. This would allow for high quality imaging of a target volume for alignment purposes, with simultaneous low dose imaging of the surrounding anatomy (e.g., for coregistration)

  13. Embryologic and anatomic basis of duodenal surgery.

    Androulakis, J; Colborn, G L; Skandalakis, P N; Skandalakis, L J; Skandalakis, J E

    2000-02-01

    The following points should be remembered by surgeons (Table 1). In writing about the head of the pancreas, the common bile duct, and the duodenum in 1979, the authors stated that Embryologically, anatomically and surgically these three entities form an inseparable unit. Their relations and blood supply make it impossible for the surgeon to remove completely the head of the pancreas without removing the duodenum and the distal part of the common bile duct. Here embryology and anatomy conspire to produce some of the most difficult surgery of the abdominal cavity. The only alternative procedure, the so-called 95% pancreatectomy, leaves a rim of pancreas along the medial border of the duodenum to preserve the duodenal blood supply. The authors had several conversations with Child, one of the pioneers of this procedure, whose constant message was to always be careful with the blood supply of the duodenum (personal communication, 1970). Beger et al popularized duodenum-preserving resection of the pancreatic head, emphasizing preservation of endocrine pancreatic function. They reported that ampullectomy (removal of the papilla and ampulla of Vater) carries a mortality rate of less than 0.4% and a morbidity rate of less than 10.0%. Surgeons should not ligate the superior and inferior pancreaticoduodenal arteries because such ligation may cause necrosis of the head of the pancreas and of much of the duodenum. The accessory pancreatic duct of Santorini passes under the gastrointestinal artery. For safety, surgeons should ligate the artery away from the anterior medial duodenal wall, where the papilla is located, thereby avoiding injury to or ligation of the duct. "Water under the bridge" applies not only to the relationship of the uterine artery and ureter but also to the gastroduodenal artery and the accessory pancreatic duct. In 10% of cases, the duct of Santorini is the only duct draining the pancreas, so ligation of the gastroduodenal artery with accidental inclusion of

  14. ACCESSORY SPLEEN: A CLINICALLY RELEVANT ANATOMIC ANOMALY

    Prachi Saffar

    2016-02-01

    Full Text Available The purpose of our study is to emphasize on the clinical relevance of the presence of accessory spleen. It is not only a well-documented anatomic anomaly, it holds special significance in the differential diagnosis of intra-abdominal tumours and lymphadenopathy. MATERIALS AND METHODS Thirty male cadavers from North Indian population above the age of 60 yrs. were dissected in the Anatomy Department of FMHS, SGT University, Gurgaon, over a period of 5 yrs. (Sep 2010-Aug 2015 and presence of accessory spleen recorded. Tissue from the accessory spleen was also subjected to routine histological processing and slide prepared by haematoxylin and eosin staining. RESULTS Accessory spleen was present in two cadavers near the splenic hilum. One was 3.9 cm in the long axis and weighed about 48.4 grams, while the other was 1.2 cm in long axis and weighed about 12.5 grams. One had a separate arterial branch from the main splenic artery; that it was splenic tissue was confirmed histologically. DISCUSSION The presence of accessory spleen is considered to be due to embryonic non-fusion of the splenic aggregate with the main mass. CONCLUSION Though accessory spleen in itself pose no clinical problems, its significance cannot be undermined. Surgeons and radiologists are advised to look for and rule out the presence of accessory spleen, especially while evaluating a case of abdominal and perineal pathology, else it may be wrongly diagnosed as malignant tumour or enlarged lymph node leading to grave consequences.

  15. Use of contextual inquiry to understand anatomic pathology workflow: Implications for digital pathology adoption

    Jonhan Ho; Orly Aridor; Parwani, Anil V.

    2012-01-01

    Background: For decades anatomic pathology (AP) workflow have been a highly manual process based on the use of an optical microscope and glass slides. Recent innovations in scanning and digitizing of entire glass slides are accelerating a move toward widespread adoption and implementation of a workflow based on digital slides and their supporting information management software. To support the design of digital pathology systems and ensure their adoption into pathology practice, the needs of ...

  16. An anatomically driven anisotropic diffusion filtering method for 3D SPECT reconstruction

    In this study, we aim to reconstruct single-photon emission computed tomography images using anatomical information from magnetic resonance imaging as a priori knowledge about the activity distribution. The trade-off between anatomical and emission data is one of the main concerns for such studies. In this work, we propose an anatomically driven anisotropic diffusion filter (ADADF) as a penalized maximum likelihood expectation maximization optimization framework. The ADADF method has improved edge-preserving denoising characteristics compared to other smoothing penalty terms based on quadratic and non-quadratic functions. The proposed method has an important ability to retain information which is absent in the anatomy. To make our approach more stable to the noise-edge classification problem, robust statistics have been employed. Comparison of the ADADF method is performed with a successful anatomically driven technique, namely, the Bowsher prior (BP). Quantitative assessment using simulated and clinical neuroreceptor volumetric data show the advantage of the ADADF over the BP. For the modelled data, the overall image resolution, the contrast, the signal-to-noise ratio and the ability to preserve important features in the data are all improved by using the proposed method. For clinical data, the contrast in the region of interest is significantly improved using the ADADF compared to the BP, while successfully eliminating noise. (paper)

  17. An Improved Medical Image Fusion Algorithm for Anatomical and Functional Medical Images

    CHEN Mei-ling; TAO Ling; QIAN Zhi-yu

    2009-01-01

    In recent years,many medical image fusion methods had been exploited to derive useful information from multimodality medical image data,but,not an appropriate fusion algorithm for anatomical and functional medical images.In this paper,the traditional method of wavelet fusion is improved and a new fusion algorithm of anatomical and functional medical images,in which high-frequency and low-frequency coefficients are studied respectively.When choosing high-frequency coefficients,the global gradient of each sub-image is calculated to realize adaptive fusion,so that the fused image can reserve the functional information;while choosing the low coefficients is based on the analysis of the neighborbood region energy,so that the fused image can reserve the anatomical image's edge and texture feature.Experimental results and the quality evaluation parameters show that the improved fusion algorithm can enhance the edge and texture feature and retain the function information and anatomical information effectively.

  18. Anatomical Variations of Anterior Osteomeatal Complex in Patients With Chronic Sinusitis

    Sarafraz

    2016-06-01

    Full Text Available Background Identifying predisposing factors for chronic sinusitis is very important. Objectives Anatomical variation of the lateral nasal wall has been investigated in several studies and it has been suggested as a predisposing factor for sinusitis. Patients and Methods In this case-control study, 74 patients who were diagnosed with chronic sinusitis (the case group based on clinical criteria and CT scan were entered into the study and 74 patients without chronic sinusitis were considered as the control group. CT scans of all patients were reviewed by a radiologist to interpret and evaluate anatomic variations of anterior osteomeatal complex including nasal deviation, concha bullosa, agger nasi, lateralized uncinate, Haller’s cells, paradoxical middle turbinate, and maxillary hypoplasia. Data were analyzed using the chi-squared test and Fisher’s exact test with SPSS software version 18. P < 0.05 was considered statistically significant. Results Results showed that the most common sinus involved was maxillary sinus. Among anatomic variations, septal deviation and concha bullosa were associated with chronic sinusitis (P < 0.01 and P < 0.032, respectively. Conclusions Among anatomic variations, septal deviation and concha bullosa are predisposing factors for chronic sinusitis and we recommend that patients with chronic sinusitis be treated by surgical procedures.

  19. Anatomic Double-Bundle Posterior Cruciate Ligament Reconstruction.

    Chahla, Jorge; Nitri, Marco; Civitarese, David; Dean, Chase S; Moulton, Samuel G; LaPrade, Robert F

    2016-02-01

    The posterior cruciate ligament (PCL) is known to be the main posterior stabilizer of the knee. Anatomic single-bundle PCL reconstruction, focusing on reconstruction of the larger anterolateral bundle, is the most commonly performed procedure. Because of the residual posterior and rotational tibial instability after the single-bundle procedure and the inability to restore the normal knee kinematics, an anatomic double-bundle PCL reconstruction has been proposed in an effort to re-create the native PCL footprint more closely and to restore normal knee kinematics. We detail our technique for an anatomic double-bundle PCL reconstruction using Achilles and anterior tibialis tendon allografts. PMID:27284530

  20. Obstetric Ultrasound Simulator With Task-Based Training and Assessment.

    Liu, Li; Kutarnia, Jason; Belady, Petra; Pedersen, Peder C

    2015-10-01

    The increasing use of point-of-care (POC) ultrasound presents a challenge in providing efficient training to POC ultrasound users for whom formal training is not readily available. In response to this need, we developed an affordable compact laptop-based obstetric ultrasound training simulator. It offers a realistic scanning experience, task-based training, and performance assessment. The position and orientation of the sham transducer are tracked with 5 DoF on an abdomen-sized scan surface with the shape of a cylindrical segment. On the simulator, user interface is rendered a virtual torso whose body surface models the abdomen of the pregnant scan subject. A virtual transducer scans the virtual torso by following the sham transducer movements on the scan surface. A given 3-D training image volume is generated by combining several overlapping 3-D ultrasound sweeps acquired from the pregnant scan subject using a Markov random field-based approach. Obstetric ultrasound training is completed through a series of tasks, guided by the simulator and focused on three aspects: basic medical ultrasound, orientation to obstetric space, and fetal biometry. The scanning performance is automatically evaluated by comparing user-identified anatomical landmarks with reference landmarks preinserted by sonographers. The simulator renders 2-D ultrasound images in real time with 30 frames/s or higher with good image quality; the training procedure follows standard obstetric ultrasound protocol. Thus, for learners without access to formal sonography programs, the simulator is intended to provide structured training in basic obstetrics ultrasound. PMID:25993700

  1. Cerebral functional connectivity periodically (de)synchronizes with anatomical constraints.

    Liégeois, Raphaël; Ziegler, Erik; Phillips, Christophe; Geurts, Pierre; Gómez, Francisco; Bahri, Mohamed Ali; Yeo, B T Thomas; Soddu, Andrea; Vanhaudenhuyse, Audrey; Laureys, Steven; Sepulchre, Rodolphe

    2016-07-01

    This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber tractography. Instead of a static analysis based on the correlation between SC and FC averaged over the entire fMRI time series, we propose a dynamic analysis, based on the time evolution of the correlation between SC and a suitably windowed FC. Assessing the statistical significance of the time series against random phase permutations, our data show a pronounced peak of significance for time window widths around 20-30 TR (40-60 s). Using the appropriate window width, we show that FC patterns oscillate between phases of high modularity, primarily shaped by anatomy, and phases of low modularity, primarily shaped by inter-network connectivity. Building upon recent results in dynamic FC, this emphasizes the potential role of SC as a transitory architecture between different highly connected resting-state FC patterns. Finally, we show that the regions contributing the most to these whole-brain level fluctuations of FC on the supporting anatomical architecture belong to the default mode and the executive control networks suggesting that they could be capturing consciousness-related processes such as mind wandering. PMID:26197763

  2. Anatomical features and clinical relevance of a persistent trigeminal artery

    Alcalá-Cerra, Gabriel; Tubbs, R S; Niño-Hernández, Lucía M

    2012-01-01

    Background: Although persistent trigeminal artery (PTA) is uncommonly identified, knowledge of this structure is essential for clinicians who interpret cranial imaging, perform invasive studies of the cerebral vasculature, and operate this region. Methods: A review of the medical literature using standard search engines was performed to locate articles regarding the PTA, with special attention with anatomical descriptions. Results: Although anatomical reports of PTA anatomy are very scarce, those were analyzed to describe in detail the current knowledge about its anatomical relationships and variants. Additionally, the embryology, classification, clinical implications, and imaging modalities of this vessel are extensively discussed. Conclusions: Through a comprehensive review of isolated reports of the PTA, the clinician can better understand and treat patients with such an anatomical derailment. PMID:23087827

  3. Ultrasound of the rotator cuff with MRI and anatomic correlation

    Magnetic resonance imaging and high-resolution ultrasound (US) are frequently used for the detection of rotator cuff tears. The diagnostic yield of US is influenced by several factors as technique, knowledge of the imaging characteristics of anatomic and pathologic findings and of pitfalls. The purpose of this article is to illustrates that the standardized high-resolution US examination of the shoulder covers the entire rotator cuff and correlates with MR imaging and anatomic sections

  4. Identification of Salicornia population: Anatomical characterization and RAPD fingerprinting

    Milić Dubravka; Luković Jadranka; Đan Mihajla; Zorić Lana; Obreht Dragana; Veselić Sanja; Anačkov G.; Petanidou Theodora

    2011-01-01

    Anatomical and Random Amplified Polymorphic DNA (RAPD) analysis of two typical populations of Salicornia europaea from Montenegro and Greece (Lesvos), one typical population of S. ramosissima from Spain and one population that belongs to the Salicornia genus from Serbia, was undertaken to develop a new strategy for identifying Salicornia plants. Anatomical variability and differentiation were examined using Principal Component Analysis (PCA) and Multivariate Discriminant Function Analys...

  5. Anatomic Dead Space Cannot Be Predicted by Body Weight

    Brewer, Lara M.; Orr, Joseph A.

    2007-01-01

    Anatomic, airway, or tracheal, dead space is the part of the tidal volume that does not participate in gas exchange. Knowledge of the size of the dead space is important for proper mechanical ventilation, especially if small tidal volumes are used. Respiratory and medical textbooks state that anatomic dead space can be estimated from the patient’s body weight. Specifically, these references suggest dead space can be predicted using a relationship of one milliliter per pound of body weight. Us...

  6. Anatomic Double-Bundle Posterior Cruciate Ligament Reconstruction

    Chahla, Jorge; Nitri, Marco; Civitarese, David; Dean, Chase S.; Moulton, Samuel G.; LaPrade, Robert F.

    2016-01-01

    The posterior cruciate ligament (PCL) is known to be the main posterior stabilizer of the knee. Anatomic single-bundle PCL reconstruction, focusing on reconstruction of the larger anterolateral bundle, is the most commonly performed procedure. Because of the residual posterior and rotational tibial instability after the single-bundle procedure and the inability to restore the normal knee kinematics, an anatomic double-bundle PCL reconstruction has been proposed in an effort to re-create the n...

  7. Anatomic anterior cruciate ligament reconstruction using an individualized approach

    Carola F. van Eck

    2014-01-01

    Full Text Available Anterior cruciate ligament (ACL reconstruction is one of the most commonly performed orthopaedic procedures. Recently, there has been a shift in interest towards reconstruction techniques that more closely restore the native anatomy of the ACL. This review paper discusses our approach to individualized anatomic ACL reconstruction, including the anatomy of the ACL, the physical exam, imaging modalities, the surgical technique for anatomic reconstruction including pre- and intraoperative considerations and our postoperative rehabilitation protocol.

  8. Proposal of anatomical terminology to call the arteries of the base of the encephalon in the monkey (Cebus paella L., 1766 Nomenclatura proposta para denominar as artérias da base do encéfalo do macaco-prego (Cebus apella L., 1766

    Jussara Rocha Ferreira

    2001-05-01

    Full Text Available Arteries of the encephalon basis of 30 monkeys (Cebus paella were studied. Arteries were injected with colored latex, fixed in formaldehyde solution at 10% and dissected under magnifying lenses. Since the animals died from natural causes they had been previously used in other experiments. Human and veterinary anatomical terminology and literature were used as a reference for the determination of vessels studied in the primates. Arteries of the encephalon base represent division branches of three vascular pedicules: the right and left internal carotid arteries and the basilar system. Vessels in the basilar system of the animal were called vertebral arteries; anterior spinal artery; anterior and posterior cerebelar arteries; pontine arteries; satellite cerebelar arteries; caudal and cranial cerebelar arteries. The basilar artery bifurcates into two posterior cerebral arteries (100%. The caudal area of the encephalon’s arterial circuit is thus constituted. Linking between the vertebro-basilar and the carotid segments is done by the posterior communicating artery, that caudally anastomizes (100% with the posterior cerebral artery. The internal carotid artery gives origin to the posterior communicating artery. The right and left internal carotid artery (intracranial portion compounds the carotid system. The following vessels were identified: middle cerebral artery; anterior cerebral artery; interhemispheric artery; olfactory arteries. Results report that Cebus paella presents an arterial pattern of relative morphological stabilityEstudaram-se as artérias da base do encéfalo do Cebus apella em 30 animais, vindos a óbito por morte natural no Zoológico de São Paulo e coletados durante 10 anos. O material recebeu injeção de látex corado, fixado em formol a 10%, e foi dissecado sob lupa. Encontramos dificuldade e denominar estes vasos. As terminologias anatômicas humana e veterinária e a recuperação da literatura nos serviram de base para

  9. Investigation of radon and thoron concentrations in a landmark skyscraper in Tokyo

    The temporal variation of the radon concentration, and the radon and thoron concentrations every 3 months for a year were measured using two types of devices in a landmark skyscraper, the Tokyo Metropolitan Government Daiichi Building. In the measurement of temporal variation of the radon concentration using a pulse type ionization chamber, the average radon concentration was 21 ± 13 Bq m-3 (2-68 Bq m-3). The measured indoor radon concentration had a strong relationship with the operation of the mechanical ventilation system and the activities of the office workers. The radon concentration also increased together with temperature. Other environmental parameters, such as air pressure and relative humidity, were not related to the radon concentration. In the long-term measurements using a passive radon and thoron discriminative monitor, no seasonal variation was observed. The annual average concentrations of radon and thoron were 16 ± 8 and 16 ± 7 Bq m-3, respectively. There was also no relationship between the two concentrations. The annual average effective dose for office workers in this skyscraper was estimated to be 0.08 mSv y-1 for 2000 working hours per year. When considering the indoor radon exposure received from their residential dwellings using the annual mean radon concentration indoors in Japan (15.5 Bq m-3), the annual average effective dose was estimated to be 0.37 mSv y-1. This value was 31 % of the worldwide average annual effective dose. (author)

  10. RTS,S: Toward a first landmark on the Malaria Vaccine Technology Roadmap.

    Kaslow, David C; Biernaux, Sophie

    2015-12-22

    The Malaria Vaccine Technology Roadmap calls for a 2015 landmark goal of a first-generation malaria vaccine that has protective efficacy against severe disease and death, lasting longer than one year. This review focuses on product development efforts over the last five years of RTS,S, a pre-erythrocytic, recombinant subunit, adjuvanted, candidate malaria vaccine designed with this goal of a first-generation malaria vaccine in mind. RTS,S recently completed a successful pivotal Phase III safety, efficacy and immunogenicity study. Although vaccine efficacy was found to be modest, a substantial number of cases of clinical malaria were averted over a 3-4 years period, particularly in settings of significant disease burden. European regulators have subsequently adopted a positive opinion under the Article 58 procedure for an indication of active immunization of children aged 6 weeks up to 17 months against malaria caused by Plasmodium falciparum and against hepatitis B. Further evaluations of the benefit, risk, feasibility and cost-effectiveness of RTS,S are now anticipated through policy and financing reviews at the global and national levels. PMID:26431982

  11. The linguistic roots of Modern English anatomical terminology.

    Turmezei, Tom D

    2012-11-01

    Previous research focusing on Classical Latin and Greek roots has shown that understanding the etymology of English anatomical terms may be beneficial for students of human anatomy. However, not all anatomical terms are derived from Classical origins. This study aims to explore the linguistic roots of the Modern English terminology used in human gross anatomy. By reference to the Oxford English Dictionary, etymologies were determined for a lexicon of 798 Modern English gross anatomical terms from the 40(th) edition of Gray's Anatomy. Earliest traceable language of origin was determined for all 798 terms; language of acquisition was determined for 747 terms. Earliest traceable languages of origin were: Classical Latin (62%), Classical Greek (24%), Old English (7%), Post-Classical Latin (3%), and other (4%). Languages of acquisition were: Classical Latin (42%), Post-Classical Latin (29%), Old English (8%), Modern French (6%), Classical Greek (5%), Middle English (3%), and other (7%). While the roots of Modern English anatomical terminology mostly lie in Classical languages (accounting for the origin of 86% of terms), the anatomical lexicon of Modern English is actually much more diverse. Interesting and perhaps less familiar examples from these languages and the methods by which such terms have been created and absorbed are discussed. The author suggests that awareness of anatomical etymologies may enhance the enjoyment and understanding of human anatomy for students and teachers alike. PMID:22461143

  12. Correlating intravital multi-photon microscopy to 3D electron microscopy of invading tumor cells using anatomical reference points.

    Matthia A Karreman

    Full Text Available Correlative microscopy combines the advantages of both light and electron microscopy to enable imaging of rare and transient events at high resolution. Performing correlative microscopy in complex and bulky samples such as an entire living organism is a time-consuming and error-prone task. Here, we investigate correlative methods that rely on the use of artificial and endogenous structural features of the sample as reference points for correlating intravital fluorescence microscopy and electron microscopy. To investigate tumor cell behavior in vivo with ultrastructural accuracy, a reliable approach is needed to retrieve single tumor cells imaged deep within the tissue. For this purpose, fluorescently labeled tumor cells were subcutaneously injected into a mouse ear and imaged using two-photon-excitation microscopy. Using near-infrared branding, the position of the imaged area within the sample was labeled at the skin level, allowing for its precise recollection. Following sample preparation for electron microscopy, concerted usage of the artificial branding and anatomical landmarks enables targeting and approaching the cells of interest while serial sectioning through the specimen. We describe here three procedures showing how three-dimensional (3D mapping of structural features in the tissue can be exploited to accurately correlate between the two imaging modalities, without having to rely on the use of artificially introduced markers of the region of interest. The methods employed here facilitate the link between intravital and nanoscale imaging of invasive tumor cells, enabling correlating function to structure in the study of tumor invasion and metastasis.

  13. Medial calcar of proximal humeral fracture as landmark in restoration of humeral length in case of hemiarthroplasty

    Hromádka, R.; Kuběna, Aleš Antonín; Šmíd, Martin; Popelka, S.

    2014-01-01

    Roč. 35, č. 5 (2014), s. 473-479. ISSN 0930-1038 Institutional support: RVO:67985556 Keywords : Fracture of proximal humerus * Calcar of humeral fracture * Reconstruction of proximal humerus * Reconstruction of humeral length * Shoulder arthroplasty * Shoulder hemiarthroplasty Subject RIV: FJ - Surgery incl. Transplants Impact factor: 1.047, year: 2014 http://library.utia.cas.cz/separaty/2013/E/smid-medial calcar of proximal humeral fracture as landmark in restoration of humeral length in case of hemiarthroplasty.pdf

  14. Somaclonal variation and comparison to mutation induced by X-rays in rice (Oryza sativa L.) by using rice landmarker

    By using rice DNA clones of landmarker set 1, set 2 and new set, RFLP analysis was carried out in plants of cv. Tsugaruotome and cv. Mutsuhomare which were derived from 300 Gy of X-ray-irradiated seeds. In the three landmarker sets were consisted of 106 genomic DNA clones and 235 cDNA clones. Each cultivar has five plants which showed polymorphism. It is considered that the occurrence of some mutation of gene concerned with DNA repairing because certain plants showed polymorphism by many landmarkers as probes. Activity of retrotransposon such as Tos17 and alteration of methylation pattern were not observed on any plants derived from X-ray-irradiated seeds. On the other hand, in plants regenerated from cultured calli, it was found the movement of Tos17 to certain area of hot spot and alteration of methylation pattern. Furthermore, it has been reported that amplification of repeated DNA segment which was not observed in the mutation induced by X-rays. Thus, on plant breeding the somaclonal variation may be more useful than the mutation induced by X-rays

  15. Anatomical connectivity of the basal ganglia : methodological developments and application to motor disorders

    Kacem, Linda

    2011-01-01

    The recent advances in magnetic resonance imaging helped understanding brain anatomy and function. Today, MR imaging is a key tool for inferring imaging-based biomarkers for most neuropathologies. In this work, we focused on the anatomical connectivity of the basal ganglia which are involved in several cortico-subcortical loops and which dysfunction is the origin of motor disorders like Huntington and Parkinson diseases and Gilles de la Tourette syndrome. We developed several tools allowing t...

  16. Gray Matter Alterations in Obsessive–Compulsive Disorder: An Anatomic Likelihood Estimation Meta-Analysis

    Rotge, Jean-Yves; Langbour, Nicolas; Guehl, Dominique; Bioulac, Bernard; Jaafari, Nematollah; Allard, Michele; Aouizerate, Bruno; Burbaud, Pierre

    2009-01-01

    Many voxel-based morphometry (VBM) studies have found abnormalities in gray matter density (GMD) in obsessive–compulsive disorder (OCD). Here, we performed a quantitative meta-analysis of VBM studies contrasting OCD patients with healthy controls (HC). A literature search identified 10 articles that included 343 OCD patients and 318 HC. Anatomic likelihood estimation meta-analyses were performed to assess GMD changes in OCD patients relative to HC. GMD was smaller in parieto-frontal cortical ...

  17. Anatomical correlates of cognitive functions in early Parkinson's disease patients.

    Roberta Biundo

    Full Text Available BACKGROUND: Cognitive deficits may occur early in Parkinson's disease (PD but the extent of cortical involvement associated with cognitive dysfunction needs additional investigations. The aim of our study is to identify the anatomical pattern of cortical thickness alterations in patients with early stage PD and its relationship with cognitive disability. METHODS: We recruited 29 PD patients and 21 healthy controls. All PD patients performed an extensive neuropsychological examination and 14 were diagnosed with mild cognitive impairment (PD-MCI. Surface-based cortical thickness analysis was applied to investigate the topographical distribution of cortical and subcortical alterations in early PD compared with controls and to assess the relationship between cognition and regional cortical changes in PD-MCI. RESULTS: Overall PD patients showed focal cortical (occipital-parietal areas, orbito-frontal and olfactory areas and subcortical thinning when compared with controls. PD-MCI showed a wide spectrum of cognitive deficits and related significant regional thickening in the right parietal-frontal as well as in the left temporal-occipital areas. CONCLUSION: Our results confirm the presence of changes in grey matter thickness at relatively early PD stage and support previous studies showing thinning and atrophy in the neocortex and subcortical regions. Relative cortical thickening in PD-MCI may instead express compensatory neuroplasticity. Brain reserve mechanisms might first modulate cognitive decline during the initial stages of PD.

  18. Anterolateral muscle sparing approach total hip arthroplasty: an anatomic and clinical study

    ZHANG Xian-long; SHEN Hao; QIN Xiao-long; WANG Qi

    2008-01-01

    Background Many kinds of approaches have been used for minimally invasive surgery of total hip arthroplasty (MIS-THA). However, until now when considering the balance of efficacy and associated surgical injury there is no approach widely accepted for MIS-THA. In this study, a modified anterolateral muscle sparing approach was developed to optimize MIS-THA. Methods Twenty adult cadaver specimens (40 hips) were used for anatomic research. The distance from anterior origin of the gluteus medius on the lilac crest to the anterior superior lilac spine was measured; the course of the superior gluteal nerve and the distances from the nerve to the regional anatomic landmarks were recorded. Simulated surgeries were performed in three fresh cadaver specimens to evaluate the soft tissues injury around incisions. From October 2004 to June 2006, 57 patients (57 hips) were treated with anterolateral muscle sparing minimally invasive total hip arthroplasty, of which 17 were femoral neck fractures, 9 osteoarthritis, 16 developmental dysplasia of hip (DDH) and 15 avascular necrosis (AVN). All the operations were performed by the same senior surgeon. Operation time, blood loss and drainage volume were recorded and the correlation between the local complications and the native anatomical characteristics was especially noted. All cases were followed for at least 12 months.Results The distance from the anterior origin of the gluteus medius to anterior superior lilac spine along the lilac crest was (61±4) mm (range, 55-68 mm), and the distance from inferior branch of the superior gluteal nerve to the anterior tubercle of the greater trochanter was (74±6)mm (range, 60-88 mm). In simulated surgeries, excessive distraction of tissue was found to be the main cause of the anterior border injury of the gluteus medius muscle. Of the 57 patients treated with anterolateral muscle sparing MIS-THA, the average incision length was 9 cm (range 7.5-13 cm). Blood transfusions were performed in 11

  19. Scaling-law for the energy dependence of anatomic power spectrum in dedicated breast CT

    Vedantham, Srinivasan; Shi, Linxi; Glick, Stephen J.; Karellas, Andrew [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States)

    2013-01-15

    Purpose: To determine the x-ray photon energy dependence of the anatomic power spectrum of the breast when imaged with dedicated breast computed tomography (CT). Methods: A theoretical framework for scaling the empirically determined anatomic power spectrum at one x-ray photon energy to that at any given x-ray photon energy when imaged with dedicated breast CT was developed. Theory predicted that when the anatomic power spectrum is fitted with a power curve of the form k f{sup -{beta}}, where k and {beta} are fit coefficients and f is spatial frequency, the exponent {beta} would be independent of x-ray photon energy (E), and the amplitude k scales with the square of the difference in energy-dependent linear attenuation coefficients of fibroglandular and adipose tissues. Twenty mastectomy specimens based numerical phantoms that were previously imaged with a benchtop flat-panel cone-beam CT system were converted to 3D distribution of glandular weight fraction (f{sub g}) and were used to verify the theoretical findings. The 3D power spectrum was computed in terms of f{sub g} and after converting to linear attenuation coefficients at monoenergetic x-ray photon energies of 20-80 keV in 5 keV intervals. The 1D power spectra along the axes were extracted and fitted with a power curve of the form k f{sup -{beta}}. The energy dependence of k and {beta} were analyzed. Results: For the 20 mastectomy specimen based numerical phantoms used in the study, the exponent {beta} was found to be in the range of 2.34-2.42, depending on the axis of measurement. Numerical simulations agreed with the theoretical predictions that for a power-law anatomic spectrum of the form k f{sup -{beta}}, {beta} was independent of E and k(E) =k{sub 1}[{mu}{sub g}(E) -{mu}{sub a}(E)]{sup 2}, where k{sub 1} is a constant, and {mu}{sub g}(E) and {mu}{sub a}(E) represent the energy-dependent linear attenuation coefficients of fibroglandular and adipose tissues, respectively. Conclusions: Numerical

  20. Scaling-law for the energy dependence of anatomic power spectrum in dedicated breast CT

    Purpose: To determine the x-ray photon energy dependence of the anatomic power spectrum of the breast when imaged with dedicated breast computed tomography (CT). Methods: A theoretical framework for scaling the empirically determined anatomic power spectrum at one x-ray photon energy to that at any given x-ray photon energy when imaged with dedicated breast CT was developed. Theory predicted that when the anatomic power spectrum is fitted with a power curve of the form k f−β, where k and β are fit coefficients and f is spatial frequency, the exponent β would be independent of x-ray photon energy (E), and the amplitude k scales with the square of the difference in energy-dependent linear attenuation coefficients of fibroglandular and adipose tissues. Twenty mastectomy specimens based numerical phantoms that were previously imaged with a benchtop flat-panel cone-beam CT system were converted to 3D distribution of glandular weight fraction (fg) and were used to verify the theoretical findings. The 3D power spectrum was computed in terms of fg and after converting to linear attenuation coefficients at monoenergetic x-ray photon energies of 20–80 keV in 5 keV intervals. The 1D power spectra along the axes were extracted and fitted with a power curve of the form k f−β. The energy dependence of k and β were analyzed. Results: For the 20 mastectomy specimen based numerical phantoms used in the study, the exponent β was found to be in the range of 2.34–2.42, depending on the axis of measurement. Numerical simulations agreed with the theoretical predictions that for a power-law anatomic spectrum of the form k f−β, β was independent of E and k(E) =k1[μg(E) −μa(E)]2, where k1 is a constant, and μg(E) and μa(E) represent the energy-dependent linear attenuation coefficients of fibroglandular and adipose tissues, respectively. Conclusions: Numerical simulations confirmed the theoretical predictions that in dedicated breast CT, the spatial frequency