Spiral Scan Research Articles

A field map updating algorithm to improve fat-water spiral imaging.

An accurate field map is essential to separate fat and water signals in a dual-echo chemical shift encoded spiral MRI scan. A rapid low-resolution B0 map prescan is usually performed before each exam. Occasional inaccuracy in these field map estimates can lead to misclassification of the water and fat signals as well as blurring artifacts in the reconstruction. The present work proposes a self-consistent model to evaluate residual field offsets according to the image data to improve the reconstruction quality and facilitate the scan efficiency. The proposed method compares the phase differences of the two-echo data after correcting for fat frequency offsets. A more accurate field map is approximated according to the phase discrepancies and improved image quality. Experiments were conducted with simulated off-resonance on a numerical phantom, five volunteer head scans, and four volunteer abdominal scans for validation. The initial reconstruction of the demonstrated examples exhibit blurring artifacts and misregistration of fat and water because of the inaccuracy of the field map. The proposed method updates the field map to amend the fat and water estimation and improve image quality. This work presents a model to improve the quality of fat-water imaging of the spiral MRI by estimating a better field map from the acquired data. It allows reducing the field map pre-scans before each spiral scan under normal circumstances to increase scan efficiency.

Improved Target Laser Capture Technology for Hexagonal Honeycomb Scanning

In laser tracking systems, capturing moving targets is a prerequisite to guaranteeing a tracking system’s performance. Previous studies have confirmed that the capture probability of hexagonal spiral scanning is higher than that for other scanning methods, but there is still room for improvement. This article proposes an improved hexagonal honeycomb scanning capture method based on hexagonal spiral scanning for a prior moving target model with a Gaussian distribution positioned within the scanning range of the visual threshold. Through experimental verification, it was found that, within the same scanning field of view, the capture probability can be increased by 3% compared to that in traditional hexagonal spiral scanning, making the capture probability greater than 98%. The improved hexagonal honeycomb structure scanning method proposed in this article provides a new solution for target acquisition problems in fields such as laser communication, laser docking, and airborne radar.

Comparative study of postmortem computed tomography (PMCT) against traditional forensic autopsy findings in fatal road traffic accidents — a pilot analysis

BackgroundVirtopsy is “a virtual alternative to the traditional autopsy, conducted with scanning and imaging technology,” mainly with the use of postmortem computed tomography (PMCT). It is still in the budding stage in India. The Department of Forensic Medicine and Toxicology, All India Institute of Medical Science, New Delhi, is the first center in the country that has established a facility for virtual autopsy. This facility aims to supplement the traditional autopsy findings and also to replace/curtail internal dissection in autopsy in the future, for which there has always been an aversion in relatives of the deceased due to emotional and religious reasons. The PMCT being a noninvasive, preservative, and objective procedure would be preferred by relatives than traditional autopsy. So, in this regard, this pilot study was conducted with the objective for comparison of PMCT vs traditional autopsy findings in fatal road traffic accidents to analyze its advantages and limitations in order to replace/augment the traditional autopsy with PMCT in the near future in road traffic accident cases.ResultsThe authors evaluated 10 cases of road traffic accident victims. In each case, an autopsy was preceded by a PMCT examination using a 16-slice Multi-Slice CT spiral scanner. The fractures of the skull, facial bones, clavicle, scapula, and vertebra were located more precisely as compared to traditional autopsy. Interpretation of the ventricular hemorrhages of the brain is much better in PMCT. PMCT should be the investigation of choice for pneumothorax, pneumoperitoneum, pneumocephalus, and hemosiuns, while it needs further exploration to detect injuries of soft tissues as out of 14 injuries only 2 were identified by PMCT.ConclusionsThe procedure of whole-body PMCT followed by region-wise CT can be studied for a better PMCT acquisition to detect soft tissue injury findings more precisely. However, the PMCT in this study was able to conclude the cause of death in a more scientific way than the traditional autopsy.

Chromatic confocal sensor-based on-machine measurement for microstructured optical surfaces featuring a self-aligned spiral center.

Chromatic confocal sensor-based on-machine measurement is effective for identifying and compensating for form errors of the ultra-precisely machined components. In this study, an on-machine measurement system was developed for an ultra-precision diamond turning machine to generate microstructured optical surfaces, for which the sensor probe adopts a uniform spiral scanning motion. To avoid the tedious spiral center alignment, a self-alignment method was proposed without additional equipment or artefact, which identified the deviation of the optical axis to the spindle axis by matching the measured surface points and the designed surface. The feasibility of the proposed method was demonstrated by numerical simulation with full consideration of noises and system dynamics. Practically, taking a typical microstructured surface as an example, the on-machine measured points were reconstructed after calibrating the alignment deviation, which was then verified by off-machine white light interferometry measurement. Avoiding tedious operations and special artefacts may significantly simplify the on-machine measurement process, thereby greatly improving the efficiency and flexibility for the measurement.

B1 and magnetization decay correction for hyperpolarized 129 Xe lung imaging using sequential 2D spiral acquisitions.

To mitigate signal variations caused by inhomogeneous RF and magnetization decay in hyperpolarized 129 Xe ventilation images using flip-angle maps generated from sequential 2D spiral ventilation images acquired in a breath-hold. Images and correction maps were compared with those obtained using conventional, 2D gradient-recalled echo. Analytical expressions to predict signal intensity and uncertainty in flip-angle measurements were derived from the Bloch equations and validated by simulations and phantom experiments. Imaging in 129 Xe phantoms and human subjects (1 healthy, 1 cystic fibrosis) was performed using 2D gradient-recalled echo and spiral. For both sequences, consecutive images were acquired with the same slice position during a breath-hold (Cartesian scan time = 15 s; spiral scan time = 5 s). The ratio of these images was used to calculate flip-angle maps and correct intensity inhomogeneities in ventilation images. Mean measured flip angle showed excellent agreement with the applied flip angle in simulations (R2 = 0.99) for both sequences. Mean measured flip angle agreed well with the globally applied flip angle (∼15% difference) in 129 Xe phantoms and in vivo imaging using both sequences. Corrected images displayed reduced coil-dependent signal nonuniformity relative to uncorrected images. Flip-angle maps were obtained using sequentially acquired, 2D spiral, 129 Xe ventilation images. Signal intensity variations caused by RF-coil inhomogeneity can be corrected by acquiring sequential single-breath ventilation images in less than 5-s scan time. Thus, this method can be used to remove undesirable heterogeneity while preserving physiological effects on the signal distribution.

Non-line-of-sight imaging based on Archimedean spiral scanning

Non-line-of-sight imaging can reconstruct objects hidden out of sight, which has drawn great attention in recent years. However, long data acquisition time is required since most of transient non-line-of-sight imaging need multi-point raster scanning of the visible wall. Here, we propose an Archimedean spiral scanning method based on confocal non-line-of-sight imaging, which greatly reduces the data acquisition time. Fewer scanning points are sufficient for imaging owing to accurate extraction of effective information. The Archimedean spiral scanning method is experimentally verified with published data and real scenes, then the curvature regularization algorithm is used to process data to achieve higher quality imaging. In the case of guaranteeing the imaging quality, the number of scanning points is reduced by an order of magnitude with the proposed method compared to traditional multi-point raster scanning method in this experiment. As a comparison, the imaging quality of Archimedean spiral scanning method is higher than those of the circular and confocal non-line-of-sight scanning methods at the same number of scanning points. This scanning method is expected to have a certain remarkable effect for real-time NLOS imaging.

Feasibility of free-breathing 19 F MRI image acquisition tocharacterize ventilation defects in CF and healthy volunteers at wash-in.

To explore the feasibility of measuring ventilation defect percentage (VDP) using 19 F MRI during free-breathing wash-in of fluorinated gas mixture with postacquisition denoising and to compare these results with those obtained through traditional Cartesian breath-hold acquisitions. Eight adults with cystic fibrosis and 5 healthy volunteers completed a single MR session on a Siemens 3T Prisma. 1 H Ultrashort-TE MRI sequences were used for registration and masking, and ventilation images with 19 F MRI were obtained while the subjects breathed a normoxic mixture of 79% perfluoropropane and 21% oxygen (O2 ). 19 F MRI was performed during breath holds and while free breathing with one overlapping spiral scan at breath hold for VDP value comparison. The 19 F spiral data were denoised using a low-rank matrix recovery approach. VDP measured using 19 F VIBE and 19 F spiral images were highly correlated (r=0.84) at 10 wash-in breaths. Second-breath VDPs were also highly correlated (r=0.88). Denoising greatly increased SNR (pre-denoising spiral SNR, 2.46 ± 0.21; post-denoising spiral SNR, 33.91 ± 6.12; and breath-hold SNR, 17.52 ± 2.08). Free-breathing 19 F lung MRI VDP analysis was feasible and highly correlated with breath-hold measurements. Free-breathing methods are expected to increase patient comfort and extend ventilation MRI use to patients who are unable to perform breath holds, including younger subjects and those with more severe lung disease.

Quantification of the methodological error in kinematic evaluation of the DRUJ using dynamic CT

Distal radio-ulnar joint (DRUJ) motion analysis using dynamic CT is gaining popularity. Following scanning and segmentation, 3D bone models are registered to (4D-)CT target frames. Imaging errors like low signal-to-noise ratio (SNR), limited Z-coverage and motion artefacts influence registration, causing misinterpretation of joint motion. This necessitates quantification of the methodological error. A cadaver arm and dynamic phantom were subjected to multiple 4D-CT scans, while varying tube charge-time product and phantom angular velocity, to evaluate the effects of SNR and motion artefacts on registration accuracy and precision. 4D-CT Z-coverage is limited by the scanner. To quantify the effects of different Z-coverages on registration accuracy and precision, 4D-CT was simulated by acquiring multiple spiral 3D-CT scans of the cadaver arm. Z-coverage was varied by clipping the 3D bone models prior to registration. The radius position relative to the ulna was obtained from the segmentation image. Apparent relative displacement seen in the target images is caused by registration errors. Worst-case translations were 0.45, 0.08 and 1.1 mm for SNR-, Z-coverage- and motion-related errors respectively. Worst-case rotations were 0.41, 0.13 and 6.0 degrees. This study showed that quantification of the methodological error enables composition of accurate and precise DRUJ motion scanning protocols.

Calculation of average acquisition probability for spiral–circular composite scanning in free space optical communication

This study investigates the acquisition probability calculation method for spiral–circular composite scanning (SCCS) in free space optical communication. The concepts of effective coverage area (ECA) and average acquisition probability (AAP) are proposed. Owing to the fast movement of the fine tracking system (FTS) of the transmitting terminal, the beam width of the transmitter is enlarged from the perspective of the receiving terminal, and the ECA is actually the enlarged area. Based on the concept of ECA, the SCCS can be considered as the traditional spiral scanning (TSS) with an enlarged beam. Then the AAP calculation method is presented to describe the acquisition probability by considering the field of uncertainty (FOU) and platform vibration simultaneously. Furthermore, the AAP builds up a connection between two existing concepts of acquisition probabilities and includes them as special cases. The effectiveness of the proposed method is validated by Monte Carlo simulations.

Differential confocal measurement of microstructure surface topography based on centering error optimization and wavelet threshold denoising

This paper proposes a precise differential confocal measurement method based on centering error optimization and wavelet threshold denoising (DCM-COWD), which can realize non-contact measurement of microstructure surface topography with high precision and efficiency. Firstly, the influence of pinhole diaphragm size and offset on axial response curve is analyzed through multiple experiments to obtain the optimal pinhole diaphragm diameter and offset of the differential confocal measurement system. Secondly, a probe centering method based on grating rotation successive approximation is designed, in order to reduce the centering error of 3D topography measurement during the spiral scanning process. Thirdly, a translation invariant (TI) wavelet threshold denoising algorithm based on median filtering and whale optimization (WOA) is proposed, which can improve the signal-to-noise ratio (SNR) and reduce the root mean square error (RMSE), and effectively suppress the Pseudo-Gibbs phenomenon of discontinuous points. Finally, the surface topography of a standard sample is measured based on DCM-COWD system. The measurement results show that the center error is within 0.75 μm and the maximum deviation is within 1.45 %. The measurement results show high accordance with the commercial white light interferometer, and the processing speed is improved by 4.17 times. The proposed method has great application potential for the precise and efficient measurement of 3D surface topography.

Evaluation of the Spiral Chest CT Scan Findings in Patients with Multiple Trauma.

To evaluate the spiral chest computed tomography (CT) scan findings in patients with multiple trauma during the COVID-19 pandemic. This retrospective study was performed on multiple trauma patients admitted to a tertiary hospital in the north of Iran in 2020. All patients with multiple trauma who had undergone a chest spiral CT were included in this study. Furthermore, the data analysis was performed through descriptive and analytical statistics using SPSS software. A total of 600 patients were included over the study period. The mean age of patients was 48.2±20.3 years. Of the total, 496 (65.3%) patients had blunt chest injuries, and 104 (34.7%) had penetrating chest injuries. Falling was the most common mechanical cause of chest trauma in 270 patients (45%). Surgical interventions were performed in 110 (18.3%) patients. A total of 276 (46%) patients had chest injuries identified by CT scans. Many patients (15.6%) had ground-glass lung opacity in the CT scan reports. Lung consolidation, pneumothorax, lung contusion, hemothorax, and rib fractures were the most common. Due to the high frequency of typical findings in spiral CT scan examinations, obtaining a reliable history of trauma severity, injury mechanism, and a detailed physical examination is recommended before prescribing a CT scan for patients.

Material Removal Capability and Profile Quality Assessment on Silicon Carbide Micropillar Fabrication with a Femtosecond Laser.

Silicon carbide (SiC) has a variety of applications because of its favorable chemical stability and outstanding physical characteristics, such as high hardness and high rigidity. In this study, a femtosecond laser with a spiral scanning radial offset of 5 μm and a spot radius of 6 μm is utilized to process micropillars on a SiC plate. The influence of pulsed laser beam energies and laser translation velocities on the micropillar profiles, dimensions, surface roughness Ra, and material removal capability (MRC) of micropillars was investigated. The processing results indicate that the micropillar has the best perpendicularity, with a micropillar bottom angle of 75.59° under a pulsed beam energy of 50 μJ in the range of 10-70 μJ, with a pulsed repetition rate of 600 kHz and a translation velocity of 0.1 m/s. As the laser translation velocity increases between 0.2 m/s and 1.0 m/s under a fixed pulsed beam energy of 50 μJ and a constant pulsed repetition rate of 600 kHz, the micropillar height decreases from 119.88 μm to 81.79 μm, with the MRC value increasing from 1.998 μm3/μJ to 6.816 μm3/μJ, while the micropillar bottom angle increases from 68.87° to 75.59°, and the Ra value diminishes from 0.836 μm to 0.341 μm. It is suggested that a combination of a higher pulsed laser beam energy with a faster laser translation speed is recommended to achieve micropillars with the same height, as well as an improved processing efficiency and surface finish.

Spiral scanning nano-profiler using normal vector tracing method.

Unlike interferometers that obtain data from the entire sample, three-dimensional (3D) measuring instruments acquire data from multiple points. A nano-profiler measures slopes at different points on the surface to determine the sample shape, while a coordinate measuring machine (CMM) utilizes contact or non-contact height displacement probes for taking measurements. Therefore, the 3D measurement time increases if the area to be measured is wide. This leads to a reduced measurement accuracy owing to environmental changes. To reduce the 3D measurement time, a nano-profiler that rotates measured objects at a constant velocity and quickly scans each measurement point by following a spiral trajectory was designed. The developed nano-profiler measures angular distribution instead of height distribution. This makes it possible to reduce the drive error during rotation. Compared to an interferometer, the measurement time was reduced from 163 to 17minwith the nano-profiler and a 10nm peak-to-valley difference was achieved. The slope measurement with spiral scanning was confirmed to be a quick and accurate shape measurement technique that can be used while manufacturing high-precision optical components.

Acceleration of spiral scanning of soil by means of continuous wavelet transform

The scientific article shows the application of the method of continuous wavelet data transform to estimate soil breaking up when tilling. Due to the high speed of experimental data processing, it became possible to reduce the total time of soil section scanning for determining its agrotechnical parameters. The reduction of time is achieved by both choosing the type of spiral along which scanning is performed and choosing the angular velocity. On the whole, scanning is performed twice as fast per one revolution depending on the studied area of the field. In some cases the number of revolutions can be reduced by 3-5 times.

Electromagnetic 2D scanning micromirror fabricated with 3D printed polymer parts for LiDAR applications

In this research, an omnidirectional scanning micromirror fabricated using a three-dimensional (3D) printing process and manual assembly is presented. The core part of the scanning micromirror is printed with photocurable resin using vat polymerization based on digital light processing. Externally fabricated 6mm-diameter aluminum-coated silicon mirror plate, self-supported coils, and permanent magnets were assembled with the printed part to provide a reflective surface and electromagnetic actuation. Two types of devices with different spring shapes were designed and tested. Modal analyses were performed for each model with different magnet combinations in the design phase. To optimize the 3D printing process, resin mixtures with various mixing ratios were tested. An optical scan angle of 8.98° has been obtained for model #1 printed with an ABS-like resin at 309 Hz and an input current of 0.2 A rms . For model #2 printed with a 9:1 mixture of ABS-like resin and B9R-2-Black resin, an optical scan angle of 6.04° at 356 Hz an input current of 0.2 A rms has been obtained. Spiral scan patterns with various modulation depths were generated using model #1. • An omnidirectional scanning micromirror fabricated using a 3D printing process • Core part of the device is printed with vat polymerization using DLP • Resin mixtures with various mixing ratios were tested to optimize the fabrication • Two types of devices with different spring geometries were designed and tested

Effect of spiral scan distance on the nanosecond-pulsed-laser lap joint of Al/Cu

The T2 Cu with a thickness of 0.2 mm and 6063 Al alloy with a thickness of 0.4 mm were joined via nanosecond pulsed laser welding in an inner spiral scanning mode. The lap configuration was Cu (upper)/Al (under). The influence of spiral scan distance (spiral distance for short) on the weld formation, microstructure and mechanical property was investigated. The results showed that circular holes and arc-shaped cracks formed on the weld surface at the spiral distance of 0.02 mm, and these defects disappeared at higher spiral distances. The tendency of porosity increased initially and decreased afterwards as the spiral distance increased. The interfacial morphology exhibited a wave-shaped structure at the spiral distance of 0.02 mm, and a continuous lump θ-CuAl2 phase was produced at the interface. When the spiral distance was larger than 0.02 mm, the wave-shaped structure disappeared and V-shaped areas were generated due to the invasion of Al element into Cu base metal. α-Al and θ-CuAl2 phases were possibly produced in these areas. The Cu-rich areas generated on the sidewall of the weld could cause the formation of θ-CuAl2. According to the tensile-shear load results, the maximum shear force reached 107.7 N at the spiral distance of 0.04 mm. The satisfactory weld formation and larger effective bounding area contributed to the superior bonding strength. Three fracture modes (button pulling out failure, weld shear failure and interface failure) were observed in this study.

Deep Learning-based calculation of patient size and attenuation surrogates from localizer Image: Toward personalized chest CT protocol optimization

PurposeExtracting water equivalent diameter (DW), as a good descriptor of patient size, from the CT localizer before the spiral scan not only minimizes truncation errors due to the limited scan field-of-view but also enables prior size-specific dose estimation as well as scan protocol optimization. This study proposed a unified methodology to measure patient size, shape, and attenuation parameters from a 2D anterior-posterior localizer image using deep learning algorithms without the need for labor-intensive vendor-specific calibration procedures. Methods3D CT chest images and 2D localizers were collected for 4005 patients. A modified U-NET architecture was trained to predict the 3D CT images from their corresponding localizer scans. The algorithm was tested on 648 and 138 external cases with fixed and variable table height positions. To evaluate the performance of the prediction model, structural similarity index measure (SSIM), body area, body contour, Dice index, and water equivalent diameter (DW) were calculated and compared between the predicted 3D CT images and the ground truth (GT) images in a slicewise manner. ResultsThe average age of the patients included in this study (1827 male and 1554 female) was 53.8 ± 17.9 (18–120) years. The DW, tube current ,and CTDIvol measured on original axial images in the external 138 cases group were significantly larger than those of the external 648 cases (P < 0.05). The SSIM and Dice index calculated between the prediction and GT for body contour were 0.998 ± 0.001 and 0.950 ± 0.016, respectively. The average percentage error in the calculation of DW was 2.7 ± 3.5 %. The error in the DW calculation was more considerable in larger patients (p-value < 0.05). ConclusionsWe developed a model to predict the patient size, shape, and attenuation factors slice-by-slice prior to spiral scanning. The model exhibited remarkable robustness to table height variations. The estimated parameters are helpful for patient dose reduction and protocol optimization.

High frame rate deformation analysis of knee cartilage by spiral dualMRI and relaxation mapping.

Daily activities including walking impose high-frequency cyclic forces on cartilage and repetitive compressive deformation. Analyzing cartilage deformation during walking would provide spatial maps of displacement and strain and enable viscoelastic characterization, which may serve as imaging biomarkers for early cartilage degeneration when the damage is still reversible. However, the time-dependent biomechanics of cartilage is not well described, and how defects in the joint impact the viscoelastic response is unclear. We used spiral acquisition with displacement-encoding MRI to quantify displacement and strain maps at a high frame rate (25 frames/s) in tibiofemoral joints. We also employed relaxometry methods (T1 , T1ρ , T2 , T2 *) on the cartilage. Normal and shear strains were concentrated on the bovine tibiofemoral contact area during loading, and the defected joint exhibited larger compressive strains. We also determined a positive correlation between the change of T1ρ in cartilage after cyclic loading and increased compressive strain on the defected joint. Viscoelastic behavior was quantified by the time-dependent displacement, where the damaged joint showed increased creep behavior compared to the intact joint. This technique was also successfully demonstrated on an in vivo human knee showing the gradual change of displacement during varus load. Our results indicate that spiral scanning with displacement encoding can quantitatively differentiate the damaged from intact joint using the strain and creep response. The viscoelastic response identified with this methodology could serve as biomarkers to detect defects in joints in vivo and facilitate the early diagnosis of joint diseases such as osteoarthritis.

Precision 1070nm Ultrafast Laser-Induced Photothrombosis of Depth-Targeted Vessels In Vivo.

The cerebrovasculature plays an essential role in neurovascular and homeostatic functions in health and disease conditions. Many efforts have been made for developing vascular thrombosis methods to study vascular dysfunction in vivo, while technical challenges remain, such as accuracy and depth-selectivity to target a single vessel in the cerebral cortex. Herein, this paper first demonstrates the evaluation and quantification of the feasibility and effects of Rose Bengal (RB)-induced photothrombosis with 720-1070nm ultrafast lasers in a raster scan. A flexible and reproducible approach is then proposed to employ a 1070nm ultrafast laser with a spiral scan for producing RB-induced occlusion, which is described as precision ultrafast laser-induced photothrombosis (PLP). Combine with two-photon microscopy imaging, this PLP displays highly precise and fast occlusion induction of various vessel types, sizes, and depths, which enhances the precision and power of the photothrombosis protocol. Overall, the PLP method provides a real-time, practical, precise, and depth-selected single-vessel photothrombosis technology in the cerebral cortex with commercially available optical equipment, which is crucial for exploring brain vascular function with high spatial-temporal resolution in the brain.

Comparison of three-dimensional digital analyses and two-dimensional histomorphometric analyses of the bone-implant interface.

Histological analysis is considered to be the gold standard method of evaluating osseointegration around a bone-implant. However, this method requires invasive specimen preparation and is capable of representing only one plane. By comparison, micro-computed tomography (μCT) is a fast and convenient method that offers three-dimensional information but is hampered by problems related to resolution and artifacts, making it a supplementary method for osseointegration analysis. To verify the reliability of μCT for osseointegration evaluation, this animal model study compared bone-to-implant contact (BIC) ratios obtained by the gold standard histomorphometric method with those obtained by the μCT method, using a rabbit tibia implant model. A sandblasted, large-grit, acid-etched (SLA) implant and a machined surface implant were inserted into each tibia of two rabbits (giving eight implants in total). Bone-implant specimens were analyzed using μCT with a spiral scan technique (SkyScan 1275) and histological sections were prepared thereafter. Three-dimensional (3D) reconstructed μCT data and four two-dimensional (2D) μCT sections, including one section corresponding to the histologic section and three additional sections rotated 45°, 90°, and 135°, were used to calculate the BIC ratio. The Pearson’s test was used for correlation analysis at a significance level of 0.05. The histomorphometric BIC and the 2D-μCT BIC showed strong correlation (r = 0.762, P = 0.046), whereas the histomorphometric BIC and 3D-μCT BIC did not (r = -0.375, P = 0.385). However, the mean BIC value of three or four 2D-μCT sections showed a strong correlation with the 3D-μCT BIC (three sections: r = 0.781, P = 0.038; four sections: r = 0.804, P = 0.029). The results of this animal model study indicate that μCT can be used to complement the histomorphometric method in bone-implant interface analyses. With the limitations of this study, 3D-μCT analysis may even have a superior aspect in that it eliminates random variables that arise as a consequence of the selected cutting direction.