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Objective: To three-dimensionally evaluate the position and morphology of the TMJ in skeletal Class I with variable degrees of overbite and overjet in comparison with normal peers., Methods: Pretreatment CBCT scans of 126 adults were retrieved. Based on the severity of overjet and overbite, the sample was divided into three main groups and six subgroups (18 patients each): the first group with a normal overbite and variable overjet degree and the second group with normal overjet and variable overbite degree. These six subgroups were compared with a third control group of normal overjet and overbite., Results: There were significant differences in vertical condylar position, vertical and anteroposterior condylar inclinations, condylar height, and significant posterior condylar positioning in severe deep overbite, compared with the control group., Conclusion: There were significant changes in the TMJ components in severe deep overbite cases. Therefore, sever deep overbite could be considered a predisposing factor for temporomandibular disorders.

Background: Dynamic contrast-enhanced ultrasound (DCE-US) is highly susceptible to motion artifacts arising from patient movement, respiration, and operator handling and experience. Motion artifacts can be especially problematic in the context of perfusion quantification. In conventional 2D DCE-US, motion correction (MC) algorithms take advantage of accompanying side-by-side anatomical B-Mode images that contain time-stable features. However, current commercial models of 3D DCE-US do not provide side-by-side B-Mode images, which makes MC challenging., Purpose: This work introduces a novel MC algorithm for 3D DCE-US and assesses its efficacy when handling clinical data sets., Methods: In brief, the algorithm uses a pyramidal approach whereby short temporal windows consisting of three consecutive frames are created to perform local registrations, which are then registered to a master reference derived from a weighted average of all frames. We applied the algorithm to imaging studies from eight patients with metastatic lesions in the liver and assessed improvements in original versus motion corrected 3D DCE-US cine using: (i) frame-to-frame volumetric overlap of segmented lesions, (ii) normalized correlation coefficient (NCC) between frames (similarity analysis), and (iii) sum of squared errors (SSE), root-mean-squared error (RMSE), and r-squared (R 2 ) quality-of-fit from fitted time-intensity curves (TIC) extracted from a segmented lesion., Results: We noted improvements in frame-to-frame lesion overlap across all patients, from 68% ± 13% without correction to 83% ± 3% with MC (p = 0.023). Frame-to-frame similarity as assessed by NCC also improved on two different sets of time points from 0.694 ± 0.057 (original cine) to 0.862 ± 0.049 (corresponding MC cine) and 0.723 ± 0.066 to 0.886 ± 0.036 (p ≤ 0.001 for both). TIC analysis displayed a significant decrease in RMSE (p = 0.018) and a significant increase in R 2 goodness-of-fit (p = 0.029) for the patient cohort., Conclusions: Overall, results suggest decreases in 3D DCE-US motion after applying the proposed algorithm., (© 2024 American Association of Physicists in Medicine.)

High frame rate three-dimensional (3D) ultrasound imaging would offer excellent possibilities for the accurate assessment of carotid artery diseases. This calls for a matrix transducer with a large aperture and a vast number of elements. Such a matrix transducer should be interfaced with an application-specific integrated circuit (ASIC) for channel reduction. However, the fabrication of such a transducer integrated with one very large ASIC is very challenging and expensive. In this study, we develop a prototype matrix transducer mounted on top of multiple identical ASICs in a tiled configuration. The matrix was designed to have 7680 piezoelectric elements with a pitch of 300 μm × 150 μm integrated with an array of 8 × 1 tiled ASICs. The performance of the prototype is characterized by a series of measurements. The transducer exhibits a uniform behavior with the majority of the elements working within the -6 dB sensitivity range. In transmit, the individual elements show a center frequency of 7.5 MHz, a -6 dB bandwidth of 45%, and a transmit efficiency of 30 Pa/V at 200 mm. In receive, the dynamic range is 81 dB, and the minimum detectable pressure is 60 Pa per element. To demonstrate the imaging capabilities, we acquired 3D images using a commercial wire phantom.

Objectives: In the Netherlands, cyclists continue to outnumber other road users in injuries and deaths. The wearing of bicycle helmets is not mandatory in the Netherlands even though research has shown that wearing bicycle helmets can reduce head and brain injuries by up to 88%. Therefore, the aim of this study was to assess the feasibility of using 3D technology to evaluate bicycle-related head injuries and helmet protection., Methods: Three patients who had been involved in a bicycle accident while wearing a helmet were subjected to multi-detector row computed tomography (MDCT) imaging after trauma. The helmets were separately scanned using the same MDCT scanner with tube voltages ranging from 80kVp to 140kVp and tube currents ranging from 10mAs to 300mAs in order to determine the best image acquisition parameters for helmets. The acquired helmet images were converted into virtual 3D surface hence Standard Tessellation Language (STL) models and merged with MDCT-derived STL models of the patients' skulls. Finally, all skull fractures and corresponding helmet damage were visualized and related., Results: Imaging bicycle helmets on an MDCT scanner proved to be feasible using a tube voltage of 120kVp and a tube current of 120mAs. Merging the resulting STL models of the patients' skull and helmet allowed the overall damage sustained by both skull and helmet to be related., Conclusion: Our proposed 3D method of assessing bicycle helmet damage and corresponding head injuries could offer valuable information for the development and design of safer bicycle helmets., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Purpose: To perform a clinical assessment of quantitative three-dimensional (3D) dynamic contrast-enhanced ultrasound (DCE-US) feasibility and repeatability in patients with liver metastasis, and to evaluate the extent of quantitative perfusion parameter sampling errors in 2D compared to 3D DCE-US imaging. Materials and Methods: Twenty consecutive 3D DCE-US scans of liver metastases were performed in 11 patients (45% women; mean age, 54.5 years; range, 48-60 years; 55% men; mean age, 57.6 years; range, 47-68 years). Pairs of repeated disruption-replenishment and bolus DCE-US images were acquired to determine repeatability of parameters. Disruption-replenishment was carried out by infusing 0.9 mL of microbubbles (Definity; Latheus Medical Imaging) diluted in 35.1 mL of saline over 8 min. Bolus consisted of intravenous injection of 0.2 mL microbubbles. Volumes-of-interest (VOI) and regions-or-interest (ROI) were segmented by two different readers in images to extract 3D and 2D perfusion parameters, respectively. Disruption-replenishment parameters were: relative blood volume (rBV), relative blood flow (rBF). Bolus parameters included: time-to-peak (TP), peak enhancement (PE), area-under-the-curve (AUC), and mean-transit-time (MTT). Results: Clinical feasibility and repeatability of 3D DCE-US using both the destruction-replenishment and bolus technique was demonstrated. The repeatability of 3D measurements between pairs of repeated acquisitions was assessed with the concordance correlation coefficient (CCC), and found to be excellent for all parameters (CCC > 0.80), except for the TP (0.74) and MTT (0.30) parameters. The CCC between readers was found to be excellent (CCC > 0.80) for all parameters except for TP (0.71) and MTT (0.52). There was a large Coefficient of Variation (COV) in intra-tumor measurements for 2D parameters (0.18-0.52). Same-tumor measurements made in 3D were significantly different ( P = 0.001) than measurements made in 2D; a percent difference of up to 86% was observed between measurements made in 2D compared to 3D in the same tumor. Conclusions: 3D DCE-US imaging of liver metastases with a matrix array transducer is feasible and repeatable in the clinic. Results support 3D instead of 2D DCE US imaging to minimize sampling errors due to tumor heterogeneity., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Aims: Microscopic evaluation of prostate specimens for both clinical and research purposes is generally performed on 5-μm-thick tissue sections. Because cross-sections give a two-dimensional (2D) representation, little is known about the actual underlying three-dimensional (3D) architectural features of benign prostate tissue and prostate cancer (PCa). The aim of this study was to show that a combination of tissue-clearing protocols and confocal microscopy can successfully be applied to investigate the 3D architecture of human prostate tissue., Methods and Results: Optical clearing of intact fresh and formalin-fixed paraffin-embedded (FFPE) clinical prostate specimens allowed us to visualize tissue structures up to a depth of 800 μm, whereas, in uncleared tissue, detection of fluorescence was only possible up to 70 μm. Fluorescent labelling with a general nuclear dye and antibodies against cytokeratin (CK) 5 and CK8-18 resulted in comprehensive 3D imaging of benign peripheral and transition prostate zones, as well as individual PCa growth patterns. After staining, clearing, and imaging, samples could still be processed for 2D (immuno)histochemical staining and DNA analysis, enabling additional molecular and diagnostic characterization of small tissue specimens., Conclusions: In conclusion, the applicability of 3D imaging to archival FFPE and fresh clinical specimens offers unlimited opportunities to study clinical and biological topics of interest in their actual 3D context., (© 2016 John Wiley & Sons Ltd.)

Objective: To discriminate clinically relevant aberrance, the accuracy of linear measurements in three-dimensional (3D) reconstructed datasets was investigated., Materials and Methods: Three partly edentulous human skulls were examined. Landmarks were defined prior to acquisition. Two CBCT-scanners and a Quad-slice CT-scanner were used. Actual distances were physically measured with calipers and defined as a reference. Subsequently, from digital DICOM datasets, 3D virtual models were generated using maximum intensity projections (MIPs). Linear measurements were performed by semi-automated image analysis. Virtual and analogue linear measurements were compared using repeated measurements in a mixed model (p ≤ 0.05)., Results: No significant difference was found among all of the digital measurements when compared to one another, whereas a significant difference was found in matched-pairs analysis between CBCT and calipers (p = 0.032). All digitally acquired data resulted in lower mean values compared to the measurements via calipers. A high level of inter-observer reliability was obtained in the digital measurements (inter-rater correlation = 0.988-0.993)., Conclusions: The reconstructed datasets led to highly consistent values among linear measurements. Yielding sub-millimeter precision, these modalities are assumed to reflect reality in a clinically irrelevant altered manner. During data acquisition and evaluation, a maximum of precision must be achieved.

Background: Laparoscopic procedures for children and adults already provide many advantages in two-dimensional (2D) vision. Only limited experiences exist for laparoscopic three-dimensional (3D) procedures in vivo. The aim of this prospective trial was to identify indications and limitations of the 3D-system in laparoscopic minimally invasive procedures in children and adults., Material and Methods: In a prospective quality assurance for laparoscopic 3D evaluation in children and adults, a total of 53 consecutive patients (22 children, 31 adults) were included. Laparoscopic transabdominal, retroperitoneal and thoracoscopic procedures were performed. For laparoscopic 3D imaging a Camera Control Unit (CCU), 3D monitor and 3D-TIPCAM® were used. Patient data, operative procedures and image quality of the 3D system were assessed., Results: Of 53 patients, 22/53 were children and 31/53 adults with a mean age of 7.6 years (range, 10 months to 15 years) and 51.5 years (range, 18 to 79 years), respectively. 8/22 children were two years old or younger. No relevant difficulties occurred with nausea, fatigue, vertigo, eye blurring or double vision, burning eyes, visual fatigue, inconvenience of visual adaptation of 3D to 2D, or medical discomforts for the surgeons in both children and adults. Difficulties were mainly addressed to the small distance of the video endoscope and the organ tissue in small children and affected mainly image definition, resolution and eye focusing., Conclusions: Advantages of 3D over 2D were mainly considered to be of relevant benefit in adults. Subjective advantages were seen in children and adults for stereoscopic depth perception, better visualization of anatomical structures and understanding of the anatomy, as well as for complex maneuvers such as suturing.

Magnetic resonance (MR) neurography has progressed in the past 2 decades because of rapid technological developments in both hardware and software. In addition to improvements in high-resolution anatomic pulse sequences, functional techniques are becoming feasible. This article presents the current state-of-the-art three-dimensional anatomic techniques, discusses the advantages of functional techniques being exploited, and portrays novel contrast types and molecular techniques that are under development and promise a bright future for this rapidly evolving technique., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: To determine whether a controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) technique can improve the image quality of three-dimensional (3D), T1-weighted gradient echo (T1w-GRE) imaging compared with the use of a standard, parallel acquisition technique (PAT)., Materials and Methods: Sixty-four patients who underwent liver MR on a 3 Tesla (T) scanner, were included in this study. Twenty minutes after the injection of 0.025 mmole/kg of gadoxetic acid, 3D T1w-GRE imaging (volumetric interpolated breathhold examination [VIBE]) was acquired twice using a generalized autocalibrating partially parallel acquisition (384 × 250 matrix, acceleration factor [AF] of 2) and a CAIPIRINHA (384 × 380 matrix, AF of 4), respectively. Qualitative image analysis was performed for two image sets., Results: CAIPIRINHA-VIBE showed better hepatic vessel clarity and lesion conspicuity than standard VIBE (P < 0.05). CAIPIRINHA-VIBE in the coronal plane also provided better results of motion artifact and liver edge sharpness than the standard VIBE (P < 0.05). Despite the more apparent PAT artifact on CAIPIRINHA-VIBE than on standard VIBE (P < 0.05), CAIPIRINHA-VIBE showed better overall image quality., Conclusion: The CAIPIRINHA-VIBE was able to provide a higher spatial resolution, T1-weighted imaging with better image quality compared with a standard VIBE., (Copyright © 2013 Wiley Periodicals, Inc.)