Multiplanar Imaging Research Articles

Clinical feasibility and validation of 3D principal strain analysis from cine MRI: comparison to 2D strain by MRI and 3D speckle tracking echocardiography

Two-dimensional (2D) strain analysis is constrained by geometry-dependent reference directions of deformation (i.e. radial, circumferential, and longitudinal) following the assumption of cylindrical chamber architecture. Three-dimensional (3D) principal strain analysis may overcome such limitations by referencing intrinsic (i.e. principal) directions of deformation. This study aimed to demonstrate clinical feasibility of 3D principal strain analysis from routine 2D cine MRI with validation to strain from 2D tagged cine analysis and 3D speckle tracking echocardiography. Thirty-one patients undergoing cardiac MRI were studied. 3D strain was measured from routine, multi-planar 2D cine SSFP images using custom software designed to apply 4D deformation fields to 3D cardiac models to derive principal strain. Comparisons of strain estimates versus those by 2D tagged cine, 2D non-tagged cine (feature tracking), and 3D speckle tracking echocardiography (STE) were performed. Mean age was 51 ± 14 (36% female). Mean LV ejection fraction was 66 ± 10% (range 37–80%). 3D principal strain analysis was feasible in all subjects and showed high inter- and intra-observer reproducibility (ICC range 0.83–0.97 and 0.83–0.98, respectively—p < 0.001 for all directions). Strong correlations of minimum and maximum principal strain were respectively observed versus the following: 3D STE estimates of longitudinal (r = 0.81 and r = −0.64), circumferential (r = 0.76 and r = −0.58) and radial (r = −0.80 and r = 0.63) strain (p < 0.001 for all); 2D tagged cine estimates of longitudinal (r = 0.81 and r = −0.81), circumferential (r = 0.87 and r = −0.85), and radial (r = −0.76 and r = 0.81) strain (p < 0.0001 for all); and 2D cine (feature tracking) estimates of longitudinal (r = 0.85 and −0.83), circumferential (r = 0.88 and r = −0.87), and radial strain (r = −0.79 and r = 0.84, p < 0.0001 for all). 3D principal strain analysis is feasible using routine, multi-planar 2D cine MRI and shows high reproducibility with strong correlations to 2D conventional strain analysis and 3D STE-based analysis. Given its independence from geometry-related directions of deformation this technique may offer unique benefit for the detection and prognostication of myocardial disease, and warrants expanded investigation.

Improving CT detection sensitivity for nodal metastases in oesophageal cancer with combination of smaller size and lymph node axial ratio.

To investigate the value of CT with inclusion of smaller lymph node (LN) sizes and axial ratio to improve the sensitivity in diagnosis of regional lymph node metastases in oesophageal squamous cell carcinoma (OSCC). The contrast-enhanced multidetector row spiral CT (MDCT) multiplanar reconstruction images of 204 patients with OSCC were retrospectively analysed. The long-axis and short-axis diameters of the regional LNs were measured and axial ratios were calculated (short-axis/long-axis diameters). Nodes were considered round if the axial ratio exceeded the optimal LN axial ratio, which was determined by receiver operating characteristic analysis. A positive predictive value (PPV) exceeding 50% is needed. This was achieved only with LNs larger than 9mm in short-axis diameter, but nodes of this size were rare (sensitivity 37.3%, specificity 96.4%, accuracy 85.8%). If those round nodes (axial ratio exceeding 0.66 ) between 7mm and 9mm in size were considered metastases as well, it might improve the sensitivity to 67.2% with a PPV of 63.9% (specificity 91.6%, accuracy 87.2%). Combination of a smaller size and axial ratio for LNs in MDCT as criteria improves the detection sensitivity for LN metastases in OSCC. • CT is widely used to assess metastatic lymph nodes. • CT has low sensitivity in detecting metastases using conventional criteria. • Diagnostic sensitivity of CT was improved by using lymph node axial ratio. • New diagnostic criteria provide greater diagnostic confidence with PPVs exceeding 50%. • New diagnostic criteria may help clinicians assess patients with oesophageal cancer.

MRI Evaluation of Lumbar Disc Degenerative Disease

Aim of the work: lumbar disc degenerative disease is most leading cause of back pain, it is the most common cause of disability at age above 45 years and 2nd most common reason for primary care physician visit. Magnetic Resonance Imaging (MRI) is the standard imaging modality for detecting disc pathology due to its advantage of lack of radiation, multi planar imaging capability, excellent spinal soft-tissue contrast and precise localization of intervertebral discs’ changes. this study aimed to evaluate the characterization, extent and changes associated with the degenerative lumbar disc disease by Magnetic Resonance Imaging. Study Design: cross-sectional and observational study. Study Sample: forty consecutive and clinically examined patients with lower back pain suggestive of lumbar disc disease. Material and Methods: 40 patients with age group between 17 and 80 years with low back pain were diagnosed on 1.5 Tesla MRI machine. The following MRI findings were noted: lumbar lordosis preserved or not, ligamentum flavum hypertrophy, facet joint arthrosis or osteophytes formation and Endplate (modic) changes, decreased disc height as compared to the upper and lower vertebral levels and loss of signals, disc bulge at different levels, Disc protrusion and disc extrusion was observed. Result: most of patient showed lossof lumbar lordosis, facet joint arthrosis, ligamentum flavum hypertrophy, Endplate (modic) changes, and osteophytes formation. Disc dehydration which is one of the earliest features of aging and disc degeneration was present in (42%) patients with the most dehydrated disc seen at L4/L5 and L5/S1. Patients with degenerative disc disease had the following disc contour abnormalities. Disc bulges (26.5%) and herniations (10.5%). Herniations were further reported as broad based herniations (9.5%), extrusions (19.0%) and the protrusions (71.4%). The most common site for bulges and herniations was L4/L5 (33.6%) and (57.1%) respectively. The most common complication of bulges and herniations was impingement of exiting nerve roots (40%) and compression of exiting nerve roots and cauda equina (47.6%) respectively. Conclusion: lumbar disc degeneration is the most common cause of low back pain. It is the most common cause of disability at age above 45 years. Plain radiograph can be helpful, but MRI is the standard imaging modality for detecting disc pathology due to its advantage of lack of radiation, multi planar imaging capability, excellent spinal soft-tissue contrast and precise localization of intervertebral discs changes.

Evaluation of peritalar subluxation in adult acquired flatfoot deformity using computed tomography and weightbearing multiplanar imaging

BackgroundThe aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other. MethodsInf-tal-sup-tal angles were compared between a stage II AAFD group (n=38) with routine MP-WB and CT scans and a control group (n=20) with preoperative CT scans for lisfranc injuries and normal hindfoot alignment after healing. ResultsThe CT inf-tal-sup-tal angle was significantly greater in AAFD compared to control (AAFD, 12±6; control, 5±4; p<0.001), but was even greater with MP-WB. There was no significant correlation between inf-tal-sup-tal angles on MP-WB and CT (Pearson’s=0.29, p=0.08). ConclusionsMP-WB imaging proved to be correlated more strongly with AAFD than CT by revealing greater hindfoot valgus. This confirmed that CT scans are useful in predicting AAFD, but cannot be used as a surrogate for MP-WB scans.

Extraskeletal and Skeletal Ewing Sarcoma Family of Tumours in Adults: A Clinico Radiological Review of 50 Cases

This review describes the imaging characteristics of Ewing sarcoma family of tumours ESFT exclusively in an adult population The magnetic resonance imaging MRI and computed tomography CT appearances in adult patients with ESFT is described The imaging characteristics in this largest case series of adult ESFT reported so far were similar to those reported in the paediatric ESFT Our incidence of extra skeletal ESFT of is the highest reported so far in the adult population and is higher than the reported incidence of in the paediatric and adolescent population MRI was found to be superior to CT scan in identifying tumour involvement of the bone marrow and in delineating the soft tissue involvement due to its multi planar imaging capability

The Use of 3D Prints to Compare the Efficacy of Three Different Calcaneal Osteotomies for the Correction of Heel Varus

Category: Hindfoot Introduction/Purpose: There are multiple surgical osteotomies described for the correction of heel varus. An adequately powered clinical comparison of these osteotomies has not been published. In this study we used 18 identical 3D prints of a patient with heel varus to compare the surgical correction obtained with a Dwyer, oblique or Z osteotomy. The adequately powered statistical results of this study quantify the unique advantages and limitations of these osteotomies. Methods: A CT scan of a patient with heel varus (16 degrees) from Charcot-Marie-Tooth disease was selected for 3D modeling. Eighteen identical 3D prints were created of an anatomical construct of the talus, calcaneus and cuboid. Coordinate frames were added to the talus and calcaneus to evaluate rotation. Six of the prints were CT scanned to establish baseline data measurements (Uncut Control Group). All 18 prints were then divided into 3 groups of 6 models each. A custom jig was used to precisely and accurately replicate a different osteotomy in each group( Dwyer, oblique or Z). A 1 cm wedge was removed from each osteotomy. Following the simulated surgeries, all 18 models were CT scanned using the same parameters as had been used for the uncut models. Anatomic and coordinate measurements were calculated using multiplanar reconstruction image processing. Coordinate measurements were established as the rotation of the calcaneal coordinate frame with respect to the talar coordinate frame. Results: A standard 1-way analysis (ANOVA) was performed on the initial data. Additionally, a Tukey Studentized Range test was run using the raw data to compare the uncut model, Dwyer, oblique and Z osteotomies for all variables that showed statistically significant differences using the ANOVA. Coronal angle correction (Figure 1): The overall ANOVA test is significant (p &lt; 0.001). Tukey post-hoc comparisons demonstrate that Z is significantly different from Oblique (mean difference = 8.8; 95pct CI [5.5,12.0]; p &lt; 0.001) and Dwyer (mean difference = 10.4; 95pct CI [7.1, 13.6]; p &lt; 0.001), but Oblique and Dwyer are not significantly different from each other (mean difference = 1.6; 95 pct CI [-1.6, 4.9]; p=0.422). Calcaneal shortening (Figure 2): The overall ANOVA test is significant (p &lt; 0.001). All group comparisons are significant except for the Z vs Uncut (p=0.919). Lateral translation (Figure 3): The overall ANOVA test is significant (p &lt; 0.001). All group comparisons are statistically significant from one another. Conclusion: The Z osteotomy provided significantly more correction in the coronal plane (varus/valgus), with no significant shortening of the calcaneus, compared to the Dwyer and oblique osteotomies. The Z osteotomy, however, produced much less correction than anticipated, with only 3 degrees of final heel valgus. The Dwyer and Oblique osteotomies remained in varus. None of the osteotomies provided more than 6mm lateral translation of the tuberosity. These results have significant application to the appropriate choice of a calcaneal osteotomy for heel varus.

Prediction of Vascular Invasion Using a 3-Point Scale Computed Tomography Grading System in Pancreatic Ductal Adenocarcinoma: Correlation With Surgery.

The aim of this study was to evaluate the correlation between a 3-point scale multidetector computed tomography (MDCT) grading system and surgical exploration in predicting vascular invasion and resectability in patients with pancreatic ductal adenocarcinoma (PDA). Fifty-five patients with surgical and pathologic confirmation of PDA were retrospectively analyzed by 3 radiologists independently. All patients had MDCT examination with multiplanar reformatted images, computed tomography (CT) angiography, and negative-contrast CT cholangiopancreatography (nCTCP). A 3-point scale CT grading system and criteria for unresectability adopting the latest guidelines were used in predicting the correlation between the invasion and resectability of 5 peripancreatic vessels and surgical grade and pathology. Tumor location was correctly identified in all patients including 2 isodense lesions by means of nCTCP. The mean sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MDCT were 92%, 83%, 95%, 78%, and 90%, respectively, in predicting tumor resectability compared with surgery and pathology and with good agreement (κ = 0.72-0.77). A correlation was observed between CT and surgical grade in predicting vascular invasion on a per-vessel basis, and the agreement presented as good to excellent (κ = 0.66-1.00). A 3-point scale CT grading system is a simple and practical method in predicting peripancreatic vessel invasion and, importantly, correlates with surgical grade and pathology. Axial images combined with multiplanar reformation, nCTCP, and CT angiography can strengthen the comprehensive evaluation of PDA for resectability.

CT Virtual Intravascular Endoscopy in the Visualization of Coronary Plaques: A Pictorial Essay

Coronary CT angiography has been increasingly used to diagnose coronary artery disease with high diagnostic value achieved. For further assessment of coronary lumen stenosis, coronary CT angiography allows characterization of coronary plaques in terms of plaque morphology and composition. Coronary plaques are commonly assessed on 2D axial and multiplanar reformatted images. However, these visualization tools are limited to viewing extraluminal changes in the coronary artery but fail to provide intraluminal appearances of the coronary wall due to presence of plaques. In this pictorial essay, we present various intraluminal appearances of coronary wall and plaques with use of 3D virtual intravascular endoscopy (VIE) visualization in relation to different types of plaques. VIE appearances of coronary stents in patients treated with coronary stenting are also briefly demonstrated to show both normal stents and in-stent restenosis. Keywords: Coronary artery disease, coronary CT angiography, plaque, virtual intravascular endoscopy, visualization.

Magnetic resonance imaging in neuropsychiatric systemic lupus erythematosus: current state of the art and novel approaches.

Systemic lupus erythematosus is a chronic, inflammatory, immune-mediated disease affecting 0.1% of the general population. Neuropsychiatric manifestations in systemic lupus erythematosus have been more frequently recognized and reported in recent years, occurring in up to 75% of patients during the disease course. Magnetic resonance imaging is known to be a useful tool for the detection of structural brain abnormalities in neuropsychiatric systemic lupus erythematosus patients because of the excellent soft-tissue contrast observed with MRI and the ability to acquire multiplanar images. In addition to conventional magnetic resonance imaging techniques to evaluate the presence of atrophy and white matter lesions, several different magnetic resonance imaging techniques have been used to identify microstructural or functional abnormalities. This review will highlight different magnetic resonance imaging techniques, including the advanced magnetic resonance imaging methods used to determine central nervous system involvement in systemic lupus erythematosus.

Accurate and Simple Screw Insertion Procedure With Patient-Specific Screw Guide Templates for Posterior C1-C2 Fixation.

Prospective clinical trial of the screw insertion method for posterior C1-C2 fixation utilizing the patient-specific screw guide template technique. To evaluate the efficacy of this method for insertion of C1 lateral mass screws (LMS), C2 pedicle screws (PS), and C2 laminar screws (LS). Posterior C1LMS and C2PS fixation, also known as the Goel-Harms method, can achieve immediate rigid fixation and high fusion rate, but the screw insertion carries the risk of injury to neuronal and vascular structures. Dissection of venous plexus and C2 nerve root to confirm the insertion point of the C1LMS may also cause problems. We have developed an intraoperative screw guiding method using patient-specific laminar templates. Preoperative bone images of computed tomography (CT) were analyzed using three-dimensional (3D)/multiplanar imaging software to plan the trajectories of the screws. Plastic templates with screw guiding structures were created for each lamina using 3D design and printing technology. Three types of templates were made for precise multistep guidance, and all templates were specially designed to fit and lock on the lamina during the procedure. Surgery was performed using this patient-specific screw guide template system, and placement of the screws was postoperatively evaluated using CT. Twelve patients with C1-C2 instability were treated with a total of 48 screws (24 C1LMS, 20 C2PS, 4 C2LS). Intraoperatively, each template was found to exactly fit and lock on the lamina and screw insertion was completed successfully without dissection of the venous plexus and C2 nerve root. Postoperative CT showed no cortical violation by the screws, and mean deviation of the screws from the planned trajectories was 0.70 ± 0.42 mm. The multistep, patient-specific screw guide template system is useful for intraoperative screw navigation in posterior C1-C2 fixation. This simple and economical method can improve the accuracy of screw insertion, and reduce operation time and radiation exposure of posterior C1-C2 fixation surgery. 3.

Prognosis of local recurrence in giant cell tumour of bone: what can we do?

Giant cell tumour of bone (GCTB) is classified as an intermediate tumour with rare metastasis, but is challenged by local recurrence. This review focuses on the role of radiological evaluation in terms of prognosis of local recurrence in GCTB. We hope to highlight the value of radiological evaluation by integrating studies on the impact of surgical treatments and non-surgical factors on local recurrence of GCTB and the current statuses of genetic and molecular prognostic factors of GCTB. Radiological evaluation can provide diverse information on tumours. As a non-invasive method, magnetic resonance imaging (MRI) is especially valuable for the diagnosis and evaluation of bone tumours due to its heightened sensitivity to soft tissue disease and multiplanar image acquisition. Imaging findings should be integrated with clinical characteristics, pathology and genetic and molecular prognostic factors to direct clinical approach and reduce the local recurrence of GCTB. Therefore, it is necessary to establish a multi-perspective evaluation system by which prognostic factors can be reliably determined. We further advocate more large-scale prospective studies. With the help of radiological evaluation, the clinic treatment of GCTB can be guided and local recurrence might be reduced; additionally, MR imaging can identify local recurrence of GCTB after surgical treatment in the early stage.

Prevalence of Femoroacetabular Impingement Morphology in Asymptomatic Adolescents.

Femoroacetabular impingement (FAI) can lead to acetabular chondrolabral damage and has been theorized as a causative factor in the development of osteoarthritis. The pathogenesis of FAI is unknown. The purpose of this study was to determine the prevalence of FAI morphology in asymptomatic adolescents. We identified children 10 to 18 years of age who had undergone a pelvic CT between 2007 and 2012. Exclusion criteria included hip pain, any hip pathology, bone tumor, long-term steroid use, history of chemotherapy or radiation therapy, nonambulatory status, neuromuscular disorder, chromosomal abnormality, and metabolic bone disease. Multiplanar reformatted images were created from axial images to calculate α angles and lateral center-edge angles (LCEA). Cam morphology was defined as an α-angle ≥55 degrees and pincer morphology as a LCEA≥40 degrees. We analyzed 558 patients (1116 hips). There were 276 males and 282 females. The average age was 14.4 years (range, 10.0 to 18.2 y). The mean α-angle was 47.9 degrees (range, 25.7 to 78 degrees) and the mean LCEA was 34.4 degrees (range, 3.9 to 58.6 degrees). Males had a significantly higher mean α-angle (49.7 vs. 46.0 degrees) (P<0.0005) and females had a significantly higher mean LCEA (35.7 vs. 33.0 degrees) (P<0.0005). Ninety-four adolescents (16.8%) had an α-angle ≥55 degrees. Cam morphology was significantly more common in males (23.9% vs. 9.9%) (P<0.001). A total of 181 adolescents (32.4%) had a LCEA≥40 degrees. Pincer morphology was equally common in males and females (29.7% vs. 35.1%) (P=0.17). Thirty-four adolescents (6.1%) had mixed morphologies. Mixed morphologies were found in 21 males (7.6%) and 13 females (4.6%) (P=0.19). The prevalence of pincer morphology increased significantly with increased age in males (P<0.001). The prevalence of cam-type FAI morphology in asymptomatic adolescents is similar to the reported prevalence in asymptomatic adults. Pincer morphology may be more common than cam morphology in adolescents. Cam morphology is more prevalent in males, whereas pincer and mixed morphologies are equally prevalent in both sexes. Level III-diagnostic.

Evaluation of condylar positioning in bimaxillary orthognathic surgery using intraoperative cone-beam computed tomography

Background: Bilateral sagittal split osteotomy (BSSO) constitutes the most used surgical method in the treatment of dentofacial deformities. Alterations in the condylar position, after the BSSO, can lead to recurrence of postoperative malocclusions, temporomandibular joint disorders (TMJ) and condylar resorption. Nowadays, the use of intraoperative cone-beam would allow to objectify the condylar position after the BSSO, avoiding deleterious effects on TMJ for wronged condylar positioning, optimising masticatory efficiency, functionality and postoperative skeletal stability. Objectives: Design a tomographic intraoperative control protocol, with O-Arm cone-beam equipment, of condylar positioning in BSSO on orthognathic surgery (OS) and evaluate its utility. Methods: Clinical prospective study made between July 2013 and August 2016 of 300 patients who underwent OS at the Oral and Maxillofacial Unit, Faculty of Medicine, School of Dentistry Clínica Alemana – Universidad del Desarrollo Clinica Alemana Santiago, Chile. In operating room, after BSSO, with radioprotection protocol, O-Arm cone-beam is used with multiplanar and three-dimensional images. The condylar position is evaluated, and if necessary, new repositioning and new control is made. Conclusions: The use of intraoperative cone-beam is a reliable technique that allows performing an immediate diagnosis of wrong condylar positioning in OS, avoiding future complications.

Mammography image restoration based on a radiographic scattering model from a single projection: Experimental study

In conventional mammography, contrast sensitivity remains limited due to the superimposition of breast tissue and scattered X-rays, which induces low visibility of lesions in the breast and, thus, an excessive number of false-positive findings. Several methods, including digital breast tomosynthesis as a multiplanar imaging modality, air-gap and slot techniques for the reduction of scatters, phase-contrast imaging as another image-contrast modality, etc., have been investigated in attempt to overcome these difficulties. However, those techniques typically require a higher imaging dose or special equipment. In this work, as an alternative, we propose a new image restoration method based on a radiographic scattering model in which the intensity of scattered X-rays and the direct transmission function of a given medium are estimated from a single projection by using the dark-channel prior. We implemented the proposed algorithm and performed an experiment to demonstrate its viability. Our results indicate that most of the structures in the examined breast were very discernable even with no adjustment in the display-window level, thus preserving superior image features and edge sharpening.

Spectrum of CT Findings in Thoracic Extranodal Non-Hodgkin Lymphoma.

Non-Hodgkin lymphoma (NHL) frequently manifests in extranodal structures in the chest, often in the form of secondary involvement but occasionally as primary disease. Because staging and treatment are affected by the presence of extranodal disease at imaging, radiologists' interpretation and management of suspicious findings are critical to patient care. Unfortunately, owing to considerable imaging overlap with other diseases, primary extranodal lymphoma is difficult to diagnose with imaging alone. Radiologists should have a heightened degree of suspicion in patients at risk (including patients with immune compromise, autoimmune diseases, or a history of stem cell or solid organ transplant) or with particular imaging appearances (including the vertebral wraparound sign, nonresolving consolidation, an infiltrative soft-tissue mass, and lesions demonstrating vascular encasement without invasion). For patients with known NHL, positron emission tomography/computed tomography (PET/CT) using fluorine 18 (18F)-labeled fluorodeoxyglucose (FDG) is now preferred for routine staging in most cases. CT remains heavily used, and identification of subtle extranodal involvement with CT can be improved with use of intravenous contrast material and careful review of multiplanar images. Pericardial effusion, pleural soft tissue (even when mild), mass-like consolidation, perilymphatic nodularity, and new lytic bone lesions are particularly suggestive of secondary involvement in a patient with known NHL. Magnetic resonance imaging is a helpful problem-solving tool when equivocal findings would change staging and treatment. This comprehensive review illustrates the spectrum of CT manifestations of extranodal NHL in the chest, including the pleura, lung, airways, heart, pericardium, esophagus, chest wall, and breast. ©RSNA, 2017.

Association between vertebral cross-sectional area and lumbar lordosis angle in adolescents.

Lumbar lordosis (LL) is more prominent in women than in men, but the mechanisms responsible for this discrepancy are poorly defined. A recent study indicates that newborn girls have smaller vertebral cross-sectional area (CSA) when compared to boys—a difference that persists throughout life and is independent of body size. We determined the relations between vertebral cross-sectional area (CSA) and LL angle and whether sex differences in lumbar lordosis are related to sex differences in vertebral CSA. Using multi-planar magnetic resonance imaging (MRI), we measured vertebral cross-sectional area (CSA) and vertebral height of the spine of 40 healthy boys and 40 girls, ages 9–13 years. Measures of the CSA of the lumbar vertebrae significantly differed between sexes (9.38 ± 1.46 vs. 7.93 ± 0.69 in boys and girls, respectively; P < 0.0001), while the degree of LL was significantly greater in girls than in boys (23.7 ± 6.1 vs. 27.6 ± 8.0 in boys and girls, respectively; P = 0.02). When all subjects were analyzed together, values for LL angle were negatively correlated to vertebral CSA (r = -0.47; P < 0.0001); this was also true when boys and girls were analyzed separately. Multivariate regression analysis indicated that vertebral CSA was independently associated with LL, even after accounting for sex, age, height or vertebral height, and weight. Similar negative relations were present when thoracic vertebrae were analyzed (Model P < 0.0001, R2 = 0.37, thoracic vertebral CSA slope P < 0.0001), suggesting that deficient vertebral cross-sectional dimensions are not merely the consequence of the anterior lumbar curvature. We conclude that vertebral CSA is negatively associated with LL, and that the greater degree of LL in females could, at least in part, be due to smaller vertebral cross-sectional dimensions. Studies are needed to examine the potential relations between vertebral CSA and spinal conditions known to be associated with increased LL, such as spondylolysis and spondylolisthesis.

Feasibility Study for Improving the Image Characteristics in Digital Tomosynthesis (DTS) Using a Compressed-Sensing (Cs)-Based Pre-Deblurring Scheme

ABSTRACTDigital tomosynthesis (DTS) has been widely used in both industrial nondestructive testing and medical x-ray imaging as a popular multiplanar imaging modality. However, although it provides some of the tomographic benefits of computed tomography (CT) at reduced dose and imaging time, the image characteristics are relatively poor due to blur artifacts originated from incomplete data sampling for a limited angular range and also aspects inherent to imaging system, including finite focal spot size of the x-ray source, detector resolution, etc. In this work, in order to overcome these difficulties, we propose an intuitive method in which a compressed-sensing (CS)-based deblurring scheme is applied to the projection images before common DTS reconstruction. We implemented the proposed deblurring algorithm and performed a systematic experiment to demonstrate its viability for improving the image characteristics in DTS. According to our results, the proposed method appears to be effective for the blurring problems in DTS and seems to be promising to our ongoing application to x-ray nondestructive testing.

A new method of 3-dimensional localization of intraocular foreign bodies using CT imaging: A role of optic nerve.

Computed tomography (CT) is considered the most sensitive method for the detection of intraocular foreign bodies (IOFBs). The purpose of this study was to evaluate a new method of 3-dimentional (3D) localization of IOFBs that takes advantage of the anatomical structure of the optic nerve and to assess the clinical outcomes using this new method. Twenty-two trauma patients with IOFBs or suspected IOFBs admitted to our hospital were scanned with multislice CT (MSCT) between July and December 2003. All scanning was performed with a 16-row spiral CT in axial plane using a sequential scanning protocol. During the scanning, the eyeball of the patient was kept stable and was not allowed to rotate internally or externally. Section collimation was set at 16 mm × 0.75 mm. Table feed was 12 mm. Reconstruction index was 0.75 mm. After scanning, the reconstructed images were loaded into a workstation to create the multiplanar reconstruction images with the aid of the 3D software. We compared the localization results with the operative findings. Multiplanar reconstruction images showed IOFBs in all 22 patients. IOFBs occurred in the eyeball of 14 patients, in the wall of the eyeball of 5 patients and in the posterior orbits of 3 patients. Different surgical procedures were designed according to the localization by this new method and all IOFBs were successfully removed. All of these foreign bodies were metallic and the localization of IOFB using MSCT was consistent with that found by operative findings. It was suggested that MSCT is a simple and effective imaging modality for the localization of IOFBs. In our study, we localized the IOFBs more quickly and accurately by taking advantage of the fixed position of the intraocular segment of the optic nerve, and determined the necessary surgical parameters.

Multiplanar evaluation of radiological findings associated with acetabular dysplasia and investigation of its prevalence in an Asian population: a CT-based study

BackgroundAcetabular dysplasia (AD) is a well-known cause of osteoarthritis (OA) of the hip, with its prevalence previously determined on plain radiography. The prevalence of preexisting AD was reported as 7.3% in a patient-based Asian population. Although computed tomography (CT) could evaluate AD in multiple planes, its prevalence using multiplanar CT images has not been reported. We investigated its prevalence with CT on coronal, axial, and sagittal planes and then determined if adding the axial and sagittal planes enhanced the investigation.MethodsWe retrospectively examined 52 consecutive Japanese individuals (mean age 59.4 years) who had undergone CT for conditions unrelated to hip disorders. The inclusion criteria of CT images were (1) reconstructed axial slice thickness of ≤1 mm and (2) normal pelvic rotations and tilt. Exclusion criteria were (1) age <20 years, (2) neither hip center could be clearly detected, (3) evidence of hip OA. The parameters used to define AD on the coronal plane were the center–edge angle, Sharp angle, acetabular index, acetabular depth ratio, and acetabulum head index. The anterior and posterior acetabular sector angles were used as axial parameters and the vertical-center-anterior margin angle as the sagittal parameter. AD prevalence was calculated using multiplanar images and then compared with the previously reported Asian prevalence using 95% confidence intervals (CI). In this study, we defined “prevalence” as the proportion of subjects who had AD in at least one hip.ResultsThe mean prevalence of AD on coronal, axial, and sagittal planes was 16.9, 15.4, and 7.7%, respectively. The lowest prevalence found by combining the three planes was 25.0% (95% CI 15.2–38.2%). This prevalence was significantly higher than that in the previously reported Asian population (7.3%).ConclusionsAt the lowest estimate, the prevalence of AD evaluated in three planes was more than twice as high as the previously reported prevalence in Asians when we investigated its prevalence using multiplanar images. The prevalence of AD in the axial and sagittal planes was not negligible. We therefore suggest that it is important to add axial and sagittal planes’ data when investigating the prevalence of AD.

3D power Doppler in the evaluation of abnormally invasive placenta.

The anomalies in placental insertion and invasion, such as placenta previa and the various forms of abnormally invasive placenta, are today a rising obstetric pathology. Two-dimensional (2D) ultrasonography is the gold standard in the diagnosis of abnormally invasive placenta (AIP), but the important feto-maternal impact of this pathology suggests the opportunity to employ all the available diagnostic techniques, such as three-dimensional (3D) power Doppler. This technique allows acquiring multiplanar images on coronal, axial and sagittal planes and with a rotational technique, it permits visualizing the placenta-bladder interface more accurately. Consequently, it allows a better study of the degree of bladder invasion, which is information that has a great impact on the subsequent counseling and management. Thus, 3D power Doppler represents an important technique complementary to 2D ultrasound in the diagnosis of AIP. The aim of this paper is to illustrate the possible applications of this procedure, referring to the main literature data.