Linear Anterior-Posterior Computed Tomography Parameters Used to Quantify Trochlear Dysplasia Are More Reliable Than Angular Measurements

2020 ◽  
Author(s):  
Peter Wilhelm Ferlic ◽  
Armin Runer ◽  
Christopher Seeber ◽  
Maria Thöni ◽  
Anna Spicher ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Trochlear Dysplasia ◽  
Angular Measurements ◽  
Anterior Posterior

Correlation Between Anterior–Posterior and Lateral Dimensions with the Effective and Water-Equivalent Diameters in Axial Images From Head Computed Tomography Examinations

2021 ◽  
Author(s):  
Winda Kusuma Dewi ◽  
Choirul Anam ◽  
Eko Hidayanto ◽  
Annisa Lidia Wati ◽  
Geoff Dougherty
Keyword(s):  
Computed Tomography ◽  
Linear Correlation ◽  
Second Order ◽  
Patient Dose ◽  
Equivalent Diameter ◽  
Effective Diameter ◽  
Head Ct ◽  
Order Polynomial ◽  
Head Computed Tomography ◽  
Anterior Posterior

Abstract The study aims to correlate the effective diameter (Deff) and water-equivalent diameter (Dw) parameters with anterior–posterior (AP), lateral (LAT) and AP + LAT dimensions in order to estimate the patient dose in head CT examinations. Seventy-four patient datasets from head CT examinations were retrospectively collected. The patient’s sizes were calculated from the middle slice using a software of IndoseCT. Dw and Deff were plotted as functions of AP, LAT and AP + LAT dimensions. The best trendline fit for LAT and AP functions was a second order polynomial, which resulted in R2 of 0.89 for Deff vs LAT, 0.88 for Dw vs LAT, 0.92 for Deff vs AP and 0.91 for Dw vs AP. A linear correlation was found for Deff vs AP + LAT, Dw vs AP + LAT and Dw vs Deff with R2 of 0.97, 0.96 and 0.98, respectively.

scholarly journals Placement of Guide-Wireless Sharp Percutaneous Pedicle Screws Utilizing Computed Tomography-Navigation and Sentinel Fluoroscopy: 2-Dimensional Operative Video

2019 ◽  
Vol 19 (2) ◽  
pp. E149-E150 ◽  
Author(s):  
Nikolay L Martirosyan ◽  
Joshua T Wewel ◽  
Juan S Uribe
Keyword(s):  
Computed Tomography ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Transverse Process ◽  
Screw Placement ◽  
Osteoporotic Bone ◽  
Screw Insertion ◽  
Institutional Review ◽  
Stab Incision ◽  
Anterior Posterior

Abstract Many established techniques exist for minimally invasive pedicle screw placement. Nearly all techniques incorporate the use of a Kershner wire (K-wire) at various points in the work-flow. The use of a K-wire adds an additional step. If its position is lost, it requires repeating all previous steps, and placement is not without complication. The use of a guide-wireless sharp screws allows the surgeon to place a pedicle screw in 1 step with several fluid maneuvers.1 The patient underwent Institutional Review Board-approved consent for this study. Following traditional computed tomography-based navigation, a stab incision is made, followed by fascial dissection with monopolar cautery. The sharp screw is placed percutaneously at the facet-transverse process junction. The precise entry point is confirmed with navigation, followed by a sentinel anterior-posterior fluoroscopic image, verifying the accuracy of the navigation. The cortical bone is traversed by malleting the sharp tip through the cortex. When the cancellous bone is engaged, the screw is then advanced through the pedicle. This set of steps allows for safe, efficient placement of percutaneous pedicle screws without the need for a guidewire. Mal-placement regarding sharp pedicle screw insertion is similar to K-wire-dependent screw placement. Surgeons must be cognoscente of exceptionally sclerotic bone, which can prove difficult to cannulate. Conversely, osteoporotic bone that is liable to a cortical pedicle breach, transverse process fracture, and/or maltrajectory are all considerations when placing a K-wireless, sharp pedicle screw. Anterior-posterior fluoroscopy is utilized to confirm accuracy of image-guided navigation and mitigate malplacement of pedicle screws.

scholarly journals Cone-beam computed tomography for assessment of palatal displaced canine position: A methodological study

2013 ◽  
Vol 84 (3) ◽  
pp. 459-466 ◽  
Author(s):  
Julia Naoumova ◽  
Heidrun Kjellberg ◽  
Reet Palm
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Cone Beam ◽  
Vertical Position ◽  
Dental Arch ◽  
Linear Measurements ◽  
Precise Position ◽  
Angular Measurements ◽  
Mean Differences ◽  
Intraexaminer Reliability

ABSTRACT Objective: To assess the inter- and intraexaminer reliability of a measurement method for evaluation of eruption angles and position of palatal displaced canines (PDCs) with cone-beam computed tomography (CBCT) images and to test the validity of the measured angles on a dry skull. Materials and Methods: Twenty patients (eight boys, 12 girls; age 11.4 ± 1.2 years) were randomly chosen among 67 patients from a study evaluating the interceptive effect of extracting the deciduous canine in children with PDCs. In total, 60 images were analyzed, because each patient had three CBCT examinations (baseline, 6-month control, and endpoint). Two observers assessed the following measurements twice: mesioangular and sagittal angle, vertical position, canine cusp tip, and canine apex to dental arch. The validity of the angular measurements was tested against angular measurements on a dry skull using mathematical formulations. Results: The inter- and intraexaminer mean differences for angular and linear measurements were all low and statistically insignificant (P > .05). The mean differences between the physical and 3D measurements were 0.5 ± 0.39 mm for the sagittal angle and 0.22 ± 0.19 mm for the mesioangular angle. Conclusions: Linear and angular measurements on CBCT images are accurate and precise and can be used to assess the precise position of a PDC.

The Horizon Sign and Frontal Bar: Two Topographic Landmarks to Confirm Endoscopic Frontal Sinusotomy

2019 ◽  
Vol 160 (4) ◽  
pp. 740-743
Author(s):  
Evan S. Walgama ◽  
Andrew Thamboo ◽  
Navarat Tangbumrungtham ◽  
Noel Ayoub ◽  
Zara M. Patel ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Endoscopic Sinus Surgery ◽  
Frontal Sinus ◽  
Case Series ◽  
Acute Angle ◽  
Sinus Surgery ◽  
Consecutive Case ◽  
Landmark Identification ◽  
Frontal Sinuses ◽  
Anterior Posterior

Confirming a thorough dissection of the frontal sinus during endoscopic sinus surgery can be challenging, and some surgeons would benefit from reliable topographic landmark identification to ensure completion of this sinus dissection. We defined (1) the “horizon sign” as the curvilinear shadow of the posterior table cast superiorly upon the anterior table of the frontal sinus at the acute angle of their meeting point and (2) the “frontal bar” as a sagittal septation at the union of the anterior/posterior tables. A cadaveric study, followed by an intraoperative consecutive case series, was performed to evaluate these 2 landmarks as indicators of complete dissection. The horizon sign was extremely reliable, identified in 100% of cadaveric frontal sinuses and intraoperative frontal sinuses. The frontal bar was present in only 67% of frontal sinuses by computed tomography. In live patients, the sensitivity and specificity of the frontal bar were 62% and 95%, respectively.

CBCT report of three intresting cases of cysts and its radiographic presentations

2021 ◽  
Vol 7 (3) ◽  
pp. 176-181
Author(s):  
A Cicilia Subbulakshmi ◽  
Saravana Bharathi ◽  
S Naveen
Keyword(s):  
Computed Tomography ◽  
Case Series ◽  
Cone Beam ◽  
Imaging Features ◽  
Jaw Cysts ◽  
Volume Calculation ◽  
3 Dimensional ◽  
Angular Measurements ◽  
Area And Volume

Accurate diagnosis with imaging and treatment planning are key in the execution of any surgical procedure.Panoramic radiography has been routinely used in dentistry to assist in clinical diagnosis, treatment procedure but it has limitations such as overlapping of anatomical areas which are of interest in the diagnosis. The invention of computed tomography (CT) had revolutionized the digital imaging though their limitations like 2-dimensional imaging features such as distortion, magnification, and superimposition were present. Cone beam computed tomography (CBCT) is rapidly gaining Interest in the medical fraternity. it was designed with the aim to offset some of the limitations of panoramic and CT imaging .CBCT ever since its inception, it had been routinely used in dentistry for its numerous advantages such as 3-dimensional and multi-planar views. Linear, Curved and angular measurements could be performed along with area and volume calculation and density. All with less radiation exposure compared to conventional computed tomography (CT) scans. In this case series three cases of jaw cysts have been presented with varied radiographic features and the role of CBCT in these cases flooding us with enormous radiographic informations which paved the way for precise surgical management.

Androgen Stimulation and Laryngeal Development

1985 ◽  
Vol 94 (6) ◽  
pp. 634-640 ◽  
Author(s):  
Neal S. Beckford ◽  
Dan Schaid ◽  
Stewart R. Rood ◽  
Bruce Schanbacher
Keyword(s):  
Animal Model ◽  
Thyroid Cartilage ◽  
Inhibitory Effect ◽  
Growth Patterns ◽  
Treatment Groups ◽  
Vocal Process ◽  
Angular Measurements ◽  
The Mean ◽  
Induced Changes ◽  
Anterior Posterior

Androgen-induced changes in laryngeal growth patterns were studied using a sheep animal model. Forty-eight lambs were divided into eight treatment groups. Lambs in seven of the groups were castrated at birth, while lambs in the eighth group served as an intact (non-castrated) control. Six groups were then treated with varying doses of testosterone and dihydrotestosterone, while the seventh served as a castrated, nontreated control. All animals were killed and gross dissections of the larynges were performed. Thirty-four linear and angular measurements were obtained from each larynx. The mean superior thyroid horn separation showed the most dramatic androgen-induced effect (p = 0.023). Laryngeal anterior-posterior diameter, superior thyroid horn height, posterior thyroid cartilage width, thyroid cartilage angle, and vocal process to arytenoid base distances all demonstrated positive dose-response relationships. Hypoandrogenic levels appeared to have an inhibitory effect upon laryngeal growth when compared to castrated controls.

scholarly journals Evaluation of Trochlear Dysplasia Severity Using Trochlear Angle: A Retrospective Study Based on Computed Tomography (CT) Scans

2018 ◽  
Vol 24 ◽  
pp. 5118-5122 ◽  
Author(s):  
Zhenyue Dong ◽  
Yingzhen Niu ◽  
Guman Duan ◽  
Yifan Song ◽  
Jianchao Qi ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Retrospective Study ◽  
Trochlear Dysplasia ◽  
Ct Scans
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