scholarly journals A novel arthrodesis technique of the sacroiliac joint

2019 ◽  
Author(s):  
Volker Fuchs
Keyword(s):  
Sacroiliac Joint ◽  
Data Sets ◽  
High Porosity ◽  
X Rays ◽  
Comprehensive Review ◽  
Sacropelvic Fixation ◽  
Detailed Explanation ◽  
Ct Data ◽  
Implant System ◽  
Individual Implant

Abstract Purpose The aim of the study was to develop an implant for fusion of the sacroiliac joint (SIJ) which, in contrast to known implant systems, can be used for isolated fusion of the SIJ as well as in combination with a lumbar instrumentation procedure or as an alternative to existing sacropelvic fixation (SPF) methods. Methods Following a comprehensive review of more than 200 high-resolution pelvic CT data sets, an implant body with high porosity and a large contact surface to the ilium and sacrum favoring integration was designed. Its shape was modeled based on the recess of the SIJ. A screw anchored in the ilium secures the position of the implant in the recess and allows connection to a lumbar instrumentation via an S1 screw. After receiving a detailed explanation and information about the novelty of the procedure, two patients with confirmed SIJ syndrome, who had undergone conservative treatment for more than 6 months without success, were operated on with a patient individual implant adapted to their anatomy. Results There were no intraoperative or postoperative complications. The postoperative CT and pelvic X-rays showed a good form fit of the implant body in the respective recess as well as correct positioning of the inserted screws. Conclusions The implant used first takes into account the special anatomy of the SIJ and also meets the requirements of a true arthrodesis of the joint. Clinical studies will now have to show whether the considerable theoretical advantages of the new implant system over existing SIJ implants and SPFs can be put into practice.

Effect of CT-based attenuation correction on uptake ratios in skeletal SPECT

2007 ◽  
Vol 46 (01) ◽  
pp. 38-42 ◽  
Author(s):  
V. Schulz ◽  
I. Nickel ◽  
A. Nömayr ◽  
A. H. Vija ◽  
C. Hocke ◽  
...  
Keyword(s):  
Vertebral Body ◽  
Facet Joint ◽  
One Dimension ◽  
Patient Specific ◽  
Data Sets ◽  
Facet Joints ◽  
Lumbar Vertebral Body ◽  
Ct System ◽  
Ct Data ◽  
Attenuation Corrected

SummaryThe aim of this study was to determine the clinical relevance of compensating SPECT data for patient specific attenuation by the use of CT data simultaneously acquired with SPECT/CT when analyzing the skeletal uptake of polyphosphonates (DPD). Furthermore, the influence of misregistration between SPECT and CT data on uptake ratios was investigated. Methods: Thirty-six data sets from bone SPECTs performed on a hybrid SPECT/CT system were retrospectively analyzed. Using regions of interest (ROIs), raw counts were determined in the fifth lumbar vertebral body, its facet joints, both anterior iliacal spinae, and of the whole transversal slice. ROI measurements were performed in uncorrected (NAC) and attenuation-corrected (AC) images. Furthermore, the ROI measurements were also performed in AC scans in which SPECT and CT images had been misaligned by 1 cm in one dimension beforehand (ACX, ACY, ACZ). Results: After AC, DPD uptake ratios differed significantly from the NAC values in all regions studied ranging from 32% for the left facet joint to 39% for the vertebral body. AC using misaligned pairs of patient data sets led to a significant change of whole-slice uptake ratios whose differences ranged from 3,5 to 25%. For ACX, the average left-to-right ratio of the facet joints was by 8% and for the superior iliacal spines by 31% lower than the values determined for the matched images (p <0.05). Conclusions: AC significantly affects DPD uptake ratios. Furthermore, misalignment between SPECT and CT may introduce significant errors in quantification, potentially also affecting leftto- right ratios. Therefore, at clinical evaluation of attenuation- corrected scans special attention should be given to possible misalignments between SPECT and CT.

scholarly journals Lower resolution Laue neutron data yield correct nanocluster formulations

2014 ◽  
Vol 70 (a1) ◽  
pp. C187-C187
Author(s):  
Alison Edwards
Keyword(s):  
Neutron Diffraction ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Precise Determination ◽  
Data Sets ◽  
X Rays ◽  
Low Resolution ◽  
Neutron Data ◽  
X Ray ◽  
Product Formulation

"The renaissance in Laue studies - at neutron sources - provides us with access to single crystal neutron diffraction data for synthetic compounds without requiring synthesis of prohibitively large amounts of compound or improbably large crystals. Such neutron diffraction studies provide vital data where proof of the presence or absence of hydrogen in particular locations is required and which cannot validly be proved by X-ray studies. Since the commissioning of KOALA at OPAL in 2009[1] we have obtained numerous data sets which demonstrate the vital importance of measuring data even where the extent of the diffraction pattern is at relatively low resolution - especially when compared to that obtainable for the same compound with X-rays. In the Laue experiment performed with a fixed radius detector, data reduction is only feasible for crystals in the ""goldilocks"" zone – where the unit cell is relatively large for the detector, a correspondingly low resolution diffraction pattern in which adjacent spots are less affected by overlap will yield more data against which a structure can be refined than a pattern of higher resolution – one where neighbouring spots overlap rendering both unusable (in our current methodology). Analogous application of powder neutron diffraction in such determinations is also considered. Single crystal neutron diffraction studies of several important compounds (up to 5KDa see figure below)[2] in which precise determination of hydride content by neutron diffraction was pivotal to the final formulation will be presented. The neutron data sets typically possess 20% or fewer unique data at substantially "lower resolution" than the corresponding X-ray data sets. Careful refinement clearly reveals chemical detail which is typically unexplored in related X-ray diffraction studies reporting high profile chemistry despite the synthetic route being one which hydride ought to be considered/excluded in product formulation."

Computer-assisted Diagnosis for Early Stage Pleural Mesothelioma

2007 ◽  
Vol 46 (03) ◽  
pp. 324-331 ◽  
Author(s):  
P. Jäger ◽  
S. Vogel ◽  
A. Knepper ◽  
T. Kraus ◽  
T. Aach ◽  
...  
Keyword(s):  
Early Stage ◽  
Computation Time ◽  
Hounsfield Unit ◽  
Computer Assisted ◽  
Clinical Test ◽  
Pleural Mesothelioma ◽  
Data Sets ◽  
Data Set ◽  
Average Computation Time ◽  
Ct Data

Summary Objectives: Pleural thickenings as biomarker of exposure to asbestos may evolve into malignant pleural mesothelioma. Foritsearly stage, pleurectomy with perioperative treatment can reduce morbidity and mortality. The diagnosis is based on a visual investigation of CT images, which is a time-consuming and subjective procedure. Our aim is to develop an automatic image processing approach to detect and quantitatively assess pleural thickenings. Methods: We first segment the lung areas, and identify the pleural contours. A convexity model is then used together with a Hounsfield unit threshold to detect pleural thickenings. The assessment of the detected pleural thickenings is based on a spline-based model of the healthy pleura. Results: Tests were carried out on 14 data sets from three patients. In all cases, pleural contours were reliably identified, and pleural thickenings detected. PC-based Computation times were 85 min for a data set of 716 slices, 35 min for 401 slices, and 4 min for 75 slices, resulting in an average computation time of about 5.2 s per slice. Visualizations of pleurae and detected thickeningswere provided. Conclusion: Results obtained so far indicate that our approach is able to assist physicians in the tedious task of finding and quantifying pleural thickenings in CT data. In the next step, our system will undergo an evaluation in a clinical test setting using routine CT data to quantifyits performance.

Structural study of the X-ray-induced enzymatic reaction of octahaem cytochromecnitrite reductase

2015 ◽  
Vol 71 (5) ◽  
pp. 1087-1094 ◽  
Author(s):  
A. A. Trofimov ◽  
K. M. Polyakov ◽  
V. A. Lazarenko ◽  
A. N. Popov ◽  
T. V. Tikhonova ◽  
...  
Keyword(s):  
Nitrite Reductase ◽  
Catalytic Reaction ◽  
Active Sites ◽  
Enzymatic Reaction ◽  
Absorbed Dose ◽  
Free Form ◽  
Data Sets ◽  
X Rays ◽  
X Ray ◽  
Site Water

Octahaem cytochromecnitrite reductase from the bacteriumThioalkalivibrio nitratireducenscatalyzes the reduction of nitrite to ammonium and of sulfite to sulfide. The reducing properties of X-ray radiation and the high quality of the enzyme crystals allow study of the catalytic reaction of cytochromecnitrite reductase directly in a crystal of the enzyme, with the reaction being induced by X-rays. Series of diffraction data sets with increasing absorbed dose were collected from crystals of the free form of the enzyme and its complexes with nitrite and sulfite. The corresponding structures revealed gradual changes associated with the reduction of the catalytic haems by X-rays. In the case of the nitrite complex the conversion of the nitrite ions bound in the active sites to NO species was observed, which is the beginning of the catalytic reaction. For the free form, an increase in the distance between the oxygen ligand bound to the catalytic haem and the iron ion of the haem took place. In the case of the sulfite complex no enzymatic reaction was detected, but there were changes in the arrangement of the active-site water molecules that were presumably associated with a change in the protonation state of the sulfite ions.

scholarly journals Clinical Incidence of Sacroiliac Joint Arthritis and Pain after Sacropelvic Fixation for Spinal Deformity

2012 ◽  
Vol 53 (2) ◽  
pp. 416 ◽  
Author(s):  
Seiji Ohtori ◽  
Takeshi Sainoh ◽  
Masashi Takaso ◽  
Gen Inoue ◽  
Sumihisa Orita ◽  
...  
Keyword(s):  
Spinal Deformity ◽  
Sacroiliac Joint ◽  
Sacropelvic Fixation ◽  
Joint Arthritis

scholarly journals AI INFLUENCE IN COVID-19 DETECTION

2021 ◽  
Vol 23 (07) ◽  
pp. 1116-1120
Author(s):  
Cijil Benny ◽  
Keyword(s):  
Neural Network ◽  
Statistical Analysis ◽  
Convolutional Neural Network ◽  
Case Reports ◽  
Ct Scans ◽  
Data Sets ◽  
X Rays ◽  
Medical Field ◽  
Primary Key ◽  
Made In

This paper is on analyzing the feasibility of AI studies and the involvement of AI in COVID interrelated treatments. In all, several procedures were reviewed and studied. It was on point. The best-analyzing methods on the studies were Susceptible Infected Recovered and Susceptible Exposed Infected Removed respectively. Whereas the implementation of AI is mostly done in X-rays and CT- Scans with the help of a Convolutional Neural Network. To accomplish the paper several data sets are used. They include medical and case reports, medical strategies, and persons respectively. Approaches are being done through shared statistical analysis based on these reports. Considerably the acceptance COVID is being shared and it is also reachable. Furthermore, much regulation is needed for handling this pandemic since it is a threat to global society. And many more discoveries shall be made in the medical field that uses AI as a primary key source.

Revision Robotic Sacroiliac Joint Fusion with Sacropelvic Fixation

2021 ◽  
pp. 65-74
Author(s):  
Colin M. Haines ◽  
Brandon J. Allen ◽  
Miles T. Guth ◽  
Christopher R. Good
Keyword(s):  
Sacroiliac Joint ◽  
Sacropelvic Fixation ◽  
Joint Fusion ◽  
Sacroiliac Joint Fusion

scholarly journals Anatomical variation of the distal femur - a CT data analysis of 24,042 knees

2018 ◽  
Vol 6 (4_suppl2) ◽  
pp. 2325967118S0003
Author(s):  
Cornelia Merz ◽  
Andre Steinert ◽  
Wiliam Kurtz ◽  
Franz Xaver Köck ◽  
Johannes Beckmann
Keyword(s):  
Distal Femur ◽  
External Rotation ◽  
Anatomical Variation ◽  
Data Sets ◽  
Medial Condyle ◽  
First Results ◽  
The Difference ◽  
Ct Data ◽  
The Individual ◽  
Femoral Size

Based on a large quantity of CT data, variations in distal femoral geometry was examined and evaluated for TKA. A retrospective study was performed on 24,042 data sets generated during the process of designing individual knee implants. Following parameters were recorded for the distal femur: Femoral absolute anterior-posterior (AP) and medial-lateral (ML) extent, lateral and medial condyle and trochlea size, distal condylar offset (DCO) between lateral and medial condyle, and the difference between medial and lateral posterior condylar offset (PCO) measured in AP direction. Variable patient geometry was found with analysis of the AP and ML extent. Approximately one-third of the patients would experience size conflicts of +/- 3 mm with standard arthroplasty systems. 62% of the knees had a DCO> 1 mm. 83% of the distal femur had a mediolateral difference in PCO> 2 mm, which corresponds to about 3° external rotation and does not correlate with the femoral size. There is a distinct variability of femoral AP and ML extent as well as offsets / asymmetries. Medial and lateral PCOs are different and do not correlate with femoral size. This first results in mismatches between size of implant and individual knee anatomy and secondly in possible softtissue release and different femoral external rotations to adapt systems with fixed distal geometry to the individual situation.

scholarly journals Lung Segmentation in 4D CT Volumes Based on Robust Active Shape Model Matching

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Gurman Gill ◽  
Reinhard R. Beichel
Keyword(s):  
Image Data ◽  
Active Shape Model ◽  
Data Sets ◽  
Segmentation Method ◽  
Data Set ◽  
Shape Model ◽  
Lung Segmentation ◽  
4D Ct ◽  
Active Shape ◽  
Ct Data

Dynamic and longitudinal lung CT imaging produce 4D lung image data sets, enabling applications like radiation treatment planning or assessment of response to treatment of lung diseases. In this paper, we present a 4D lung segmentation method that mutually utilizes all individual CT volumes to derive segmentations for each CT data set. Our approach is based on a 3D robust active shape model and extends it to fully utilize 4D lung image data sets. This yields an initial segmentation for the 4D volume, which is then refined by using a 4D optimal surface finding algorithm. The approach was evaluated on a diverse set of 152 CT scans of normal and diseased lungs, consisting of total lung capacity and functional residual capacity scan pairs. In addition, a comparison to a 3D segmentation method and a registration based 4D lung segmentation approach was performed. The proposed 4D method obtained an average Dice coefficient of0.9773±0.0254, which was statistically significantly better (pvalue≪0.001) than the 3D method (0.9659±0.0517). Compared to the registration based 4D method, our method obtained better or similar performance, but was 58.6% faster. Also, the method can be easily expanded to process 4D CT data sets consisting of several volumes.

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