Coronal Multiplanar Reformatted Images Research Articles

Does Resampled Image Data Offer Quantitative Image Quality Benefit for Pediatric CT?

Acquiring CT images with thin slices can improve resolution and detectability, but cause an increase in the image noise. To compensate for the additional image noise, the kVp or mA can be increased, which carries a dose penalty to the patient. We investigate the image quality achieved in MPR images reformatted from different slice thicknesses 0.625 mm and 5 mm, to determine if a thicker slice could be resampled to smaller thickness with minimal loss of image information. Catphan?600 phantom was imaged using selected kVp/mA settings (80 kVp/250 mA, 100 kVp/ 150 mA and 120 kVp/200 mA) to generate slices with thicknesses of 0.625 mm and 5 mm using a GE Discovery HD750 64-slice CT scanner to investigate the impact of the acquisition slice thickness on the overall image quality in MPRs. Measurements of image noise, uniformity, contrast-to-noise ratio (CNR), low contrast detectability and limiting spatial resolution were performed on axial and coronal multiplanar reformatted images (MPRs). Increased noise, reduced contrast-to-noise ratio, and improved limiting spatial resolution and low contrast detection were observed in 2 mm coronal MPRs generated with 0.625 mm thin slices when compared to the MPRs from 5 mm thick slices. If the 2 mm coronal MPRs acquired with 5 mm slices are resampled to 0.6 mm slice thickness, the reductions in limiting resolution and low contrast detection are compensated, although with reduced uniformity and increased image noise. Thick slice image acquisitions yield better CNR and less noise in the images, whereas thin slices exhibited improved spatial resolution and low contrast detectability. Retrospectively resampling into thinner slices before obtaining the coronal MPRs provided a balance between image smoothness and identifying fine image detail. Which approach provides the optimal image quality may also depend on the imaging task, size and composition of the features of interest, and radiologist preference.

A fatal condition in the thoracic aorta

A fatal condition in the thoracic aorta

Radiologic Assessment of the Relationship Between the Maxillary Artery and the Lateral Pterygoid Muscle

The course of the second part of the maxillary can vary among different races. The aim of this study was to evaluate the relation between the maxillary artery and the lateral pterygoid muscle in a white population sample on computed tomographic (CT) angiograms. We retrospectively reviewed multidetector CT angiograms of 209 patients (134 men and 75 women). The images were taken using a 64-row multidetector CT scanner. The imaging parameters were 0.5 × 64-mm slice thickness, 0.5- or 0.3-mm increment, 120 kV, 250 mA s, 0.5-second rotation time, 0.641 pitch, and 512 matrix. The relationship between the pterygoid portion of the maxillary artery and the lateral pterygoid muscle was assessed on axial, sagittal, and coronal multiplanar reformatted images with the Vitrea 2 software program. A total of 572 maxillary arteries in 286 patients were assessed. Of these maxillary arteries, 418 (68.42%) had a superficial course to the pterygoid muscle and 132 (31.58%) had a deep course. In 165 (78.94%) of 286 patients, there was a cross-lateral symmetry of the course of the artery; that is, both vessels were superficial or deep. In 44 (21.1%) of 209 patients, an asymmetric course was observed. Because of the incidence of the asymmetric presentations, generalization regarding such a controversial topic should not be based on findings of cadaveric studies and each hemi head should be considered as a single entity. Therefore, advanced imaging systems are useful tools in preoperative planning and play a key role in the avoidance of hemorrhagic complications.

Detection of focal hepatic lesions with 3-T MRI: comparison of two-dimensional and three-dimensional T2-weighted sequences

To evaluate whether incorporation of a 3D turbo spin-echo sequence during T2-weighted MR imaging improves the detection of focal hepatic lesions by 3T MR imaging. Seventy-nine consecutive patients including 67 patients with 62 malignant and 71 benign lesions and 12 patients having no hepatic lesion underwent respiratory-triggered fat-suppressed axial T2-weighted turbo spin-echo imaging using two-dimensional (2D-TSE) and 3D (3D-TSE) sequences. Coronal multiplanar reformatted images (MPR-3D-TSE) were generated from 3D-TSE images. Breath-hold fat-suppressed 2D axial T2-weighted half-Fourier turbo spin-echo (HF-2D-TSE) images were combined for reading. Two independent radiologists reviewed three imaging sets, (1) 2D-TSE and HF-2D-TSE, (2) 3D-TSE and HF-2D-TSE, and (3) 3D-TSE, HF-2D-TSE and MPR-3D-TSE, for detection of malignant and benign lesions. Lesion-to-liver contrast ratio (CR) and the conspicuity of anatomical boundaries were assessed. For benign lesions, lesion-to-liver CRs with 3D-TSE (2.77 ± 1.91, p = .0002) and MPR-3D-TSE (2.47 ± 1.42, p = .012) were higher than with 2D-TSE (2.13 ± 1.80). Sensitivity for lesions of ≤ 10-mm was higher with 3D-TSE (86 %, p = .0039) and MPR-3D-TSE (84 %, p = .0078) than with 2D-TSE (72 %). However, the edge of left lateral lobe was less conspicuous with 3D-TSE (p < .0001) and MPR-3D-TSE (p = .0003) than with 2D-TSE because of susceptibility artifacts. Incorporation of 3D T2-weighted sequence may incrementally improve the detection of focal hepatic lesions.

Successful Right Middle Lobe Resection after Left Pneumonectomy with Selective Lobar Blockade Assisted by Preoperative Coronal Multiplanar Reformation Images on 64 Slice Multidetector Computed Tomography

Selective isolation of a pulmonary lobe is indispensable in patients who have undergone pneumonectomy and require surgery of the remaining lung. The use of a bronchial blocker is associated with the following problems: 1) placement can require considerable time; 2) suction is often necessary to expedite lung collapse; and 3) the position of the blocker sometimes must be corrected intraoperatively with the use of fiberoptic bronchoscopy. To solve these problems, it is useful for physicians to simulate the positioning of blockers on preoperative coronal multiplanar reformation images obtained by 64- slice multidetector computed tomography (MDCT) and to be familiar with airway devices for lung isolation. We describe the use of selective lobar blockade with an endobronchial blocker assisted by preoperative coronal multiplanar reformation images on 64-MDCT in a patient who had undergone a left pneumonectomy.

Multi-Detector Row Computed Tomographic Evaluation of Bronchopleural Fistula

To evaluate the usefulness of multi-detector row computed tomography (CT) in the diagnosis of bronchopleural fistula (BPF) and to correlate CT features with clinical, bronchoscopic, and surgical findings. Twenty-four patients had a final diagnosis of BPF. Thin-section axial and coronal multiplanar reformation images from multi-detector row CT datasets were assessed by 2 radiologists in consensus. The CT direct sign of BPF was a fistulous tract between the bronchus or lung and pleural space. The indirect signs were air bubbles beneath the bronchial stump or suspected fistula. Computed tomography demonstrated fistulous tract (central type, 3; peripheral type, 11) or indirect signs of BPF (central type, 3; peripheral type, 6), whereas bronchoscopy demonstrated 2 fistula openings (all central type) and indirect signs of BPF (central type, 2; peripheral type, 1). Thin-section axial and multiplanar reformation images are helpful in the diagnosis of BPF. Multi-detector row CT can be an initial diagnostic modality of BPF.

Staging of T3 and T4 Gastric Carcinoma with Multidetector CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion

To determine the added value of multiplanar reformation (MPR) images combined with computed tomographic (CT) images in staging of T4 gastric cancers. The institutional review board approved this retrospective study and waived informed consent. One hundred forty-nine consecutive patients (99 men [age range, 33-85 years; mean age, 63.1 years] and 50 women [age range, 30-85 years; mean age, 57.1 years]; age range, 30-85 years; mean age, 61.1 years) with pathologically and/or surgically confirmed T3 (n = 110) or T4 tumors (n = 39), with invasion of the transverse colon or mesocolon (n = 23), pancreas (n = 16), diaphragm (n = 4), liver (n = 3), and/or spleen (n = 1) were included. Two experienced radiologists independently reviewed 4-mm-thick transverse CT images and, 10 weeks later, reviewed both transverse CT and additional coronal and sagittal MPR images to assess tumor invasion in each of the aforementioned five adjacent organs. Receiver operating characteristic (ROC) analyses and weighted kappa statistics were obtained to evaluate reader performance and agreement in identifying tumor invasion. With addition of MPR images, the area under the ROC curve (AUC) led to a significant increase in the prediction of adjacent organ invasion in per-organ analyses (0.88 vs 0.95 for reader 1 [P = .01], 0.88 vs 0.98 for reader 2 [P < .001]) and identification of T4 tumors in per-patient analyses (0.79 vs 0.91 for reader 1 [P = .006], 0.78 vs 0.96 for reader 2 [P < .001]). In the five analyzed organs, AUC was significantly increased in regard to invasion of the transverse colon or mesocolon and pancreas; separate analysis was not performed for the diaphragm, liver, and spleen because of the small number of true invasions. Interobserver agreement increased in per-organ (kappa = 0.43 vs 0.67) and per-patient (kappa = 0.42 vs 0.62) analyses. Adding MPR images to transverse CT images improves the capability for distinguishing T3 from T4 gastric cancer and prediction of adjacent organ invasion. http://radiology.rsnajnls.org/cgi/content/full/2502071872/DC1.

Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A feasibility study

Purpose: To evaluate if coronal reformatted images can be used for primary interpretation of MDCT of the abdomen and pelvis using 64-slice MDCT. Materials and methods: IRB approval was obtained. We reviewed MDCT studies of the abdomen and pelvis of 220 consecutive patients performed with 64 row MDCT with constant scanning parameters. Based on a 0.625 mm raw data set, transverse images were reconstructed at 5 mm and coronal images at 3 mm using standard reconstruction algorithms. Reader familiarity was achieved by simultaneous evaluation of transverse and coronal reformats in an initial group of 20 separate cases for findings in consensus. Two subsequent phases of image analysis were then performed in two groups of 100 patients each. In the first phase two radiologists evaluated the added utility of simultaneous review of MDCT of transverse and coronal reformatted images over transverse images alone in 100 consecutive patients referred for MDCT of the abdomen and pelvis. In the second phase, the same radiologists evaluated whether coronal multiplanar reformats could be used for primary interpretation of MDCT of the abdomen and pelvis in a separate but similar cohort of 100 consecutive abdominopelvic MDCT studies. The number of lesion(s), their location, size of smallest lesion, presence of artifacts and likely diagnosis were noted at each image interpretation. Image quality and confidence for interpretation was evaluated using five-point and three-point scale, respectively. The time required for primary interpretation of coronal reformats and transverse images were recorded. Statistical analysis was performed using Wilcoxon signed rank test. Results: Both readers detected additional findings (n = 37, 35), respectively, on simultaneous review of transverse and coronal reformats as compared with transverse images alone (p < 0.001). Excellent interobserver agreement was noted (r = 0.94–0.96). Both readers detected additional findings (n = 62, 53), respectively, on independent review of coronal reformats as compared with transverse images alone (p < 0.001). Readers’ confidence was also found to be higher on coronal evaluations as compared to axial images (p < 0.01). There was good interobserver agreement between the two readers. Conclusion: Independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners show promise as the preferred orientation and can be useful for primary interpretation of MDCT of the abdomen and pelvis. Published by Elsevier Ireland Ltd

CSF Leaks: Correlation of High-Resolution CT and Multiplanar Reformations with Intraoperative Endoscopic Findings

Skull base defects can result in CSF leaks, with meningitis as a potential complication. Surgeons are now routinely repairing these leaks via a nasal endoscopic approach. Accurate preoperative imaging is essential for surgical planning. A variety of imaging regimens have been employed, including axial and direct coronal CT, CT cisternography with iodinated contrast, radionuclide cisternography, and MR imaging. Now that multidetector helical CT is available, the purpose of this study was to determine how well coronal and sagittal multiplanar reformatted (MPR) images generated from a high-resolution axial dataset correlate with intraoperative findings in a group of patients with clinically proved CSF leaks. We retrospectively reviewed imaging findings and surgical records of 19 patients who presented to our tertiary care institution during a 2.5-year period with clinically proved CSF leak. Patients underwent preoperative imaging with high-resolution helical CT (section collimation, 10 patients with 0.625-mm and 9 patients with 1.25-mm images), with MPR images processed by a neuroradiologist at a workstation. Two neuroradiologists, blinded to the intraoperative findings, determined the location and size of the skull base defects. All patients underwent endoscopic evaluation by an experienced sinonasal otolaryngologist, who confirmed the site of the CSF leak by direct inspection and measured the corresponding osseous defect. CT was considered accurate if it correctly localized the CSF leak and was within 2 mm of the endoscopic measurement. At endoscopy, 22 leaks of CSF were identified in 18 of 19 patients. CT correctly predicted the site of the leak in 20 (91%) of 22 cases and was accurate (within 2 mm of the endoscopic measurement) in 15 (75%) of 20 cases preoperatively localized. The CT measurement of the skull base defect differed from the endoscopic size in 5 (25%) of 20 cases, ranging from 7.4 mm below to 13 mm above the intraoperative measurement. When analysis was limited to the subgroup of 10 patients who had 0.625-mm axial images, the accuracy was improved, and of the 11 CSF leaks described at CT, all were verified at endoscopy. In addition, the submillimeter CT accurately measured the size of the osseous defect in 9 (82%) of 11 cases. In the remaining 2 (18%) of 11 cases, CT minimally overestimated the size of the osseous defect by only 3 mm. Axial images, and coronal, sagittal, and oblique MPR images generated from high-resolution axial CT performed well preoperatively, localizing the skull base defect responsible for the CSF leak. However, active manipulation of the axial dataset at a workstation is crucial in identifying and correctly describing these lesions. When submillimeter collimation is available, measurement of the osseous defects are accurate most of the time.

Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A feasibility study

Purpose To evaluate if coronal reformatted images can be used for primary interpretation of MDCT of the abdomen and pelvis using 64-slice MDCT. Materials and methods IRB approval was obtained. We reviewed MDCT studies of the abdomen and pelvis of 220 consecutive patients performed with 64 row MDCT with constant scanning parameters. Based on a 0.625 mm raw data set, transverse images were reconstructed at 5 mm and coronal images at 3 mm using standard reconstruction algorithms. Reader familiarity was achieved by simultaneous evaluation of transverse and coronal reformats in an initial group of 20 separate cases for findings in consensus. Two subsequent phases of image analysis were then performed in two groups of 100 patients each. In the first phase two radiologists evaluated the added utility of simultaneous review of MDCT of transverse and coronal reformatted images over transverse images alone in 100 consecutive patients referred for MDCT of the abdomen and pelvis. In the second phase, the same radiologists evaluated whether coronal multiplanar reformats could be used for primary interpretation of MDCT of the abdomen and pelvis in a separate but similar cohort of 100 consecutive abdominopelvic MDCT studies. The number of lesion(s), their location, size of smallest lesion, presence of artifacts and likely diagnosis were noted at each image interpretation. Image quality and confidence for interpretation was evaluated using five-point and three-point scale, respectively. The time required for primary interpretation of coronal reformats and transverse images were recorded. Statistical analysis was performed using Wilcoxon signed rank test. Results Both readers detected additional findings ( n = 37, 35), respectively, on simultaneous review of transverse and coronal reformats as compared with transverse images alone ( p < 0.001). Excellent interobserver agreement was noted ( r = 0.94–0.96). Both readers detected additional findings ( n = 62, 53), respectively, on independent review of coronal reformats as compared with transverse images alone ( p < 0.001). Readers’ confidence was also found to be higher on coronal evaluations as compared to axial images ( p < 0.01). There was good interobserver agreement between the two readers. Conclusion Independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners show promise as the preferred orientation and can be useful for primary interpretation of MDCT of the abdomen and pelvis.

MDCT of Pancreatic Adenocarcinoma: Optimal Imaging Phases and Multiplanar Reformatted Imaging

The objective of our study was to evaluate the individual contributions of arterial, pancreatic parenchymal, and portal venous phase (PVP) images and the utility of coronal and sagittal multiplanar reformatted (MPR) images in the assessment of pancreatic adenocarcinoma using triple-phase MDCT. Thirty-one patients with and 35 patients without pancreatic adenocarcinoma underwent triple-phase MDCT. Three radiologists independently attempted to detect pancreatic adenocarcinoma and assess local extension using the MDCT images in five sessions. The first three sessions involved sets of images obtained in arterial phase, pancreatic parenchymal phase, and PVP separately and respectively. In the fourth session, a combination of axial images from all phases was evaluated. During the fifth session, radiologists had access to coronal and sagittal MPR images together with the axial images obtained in all phases. Results were compared with surgical findings using receiver operating characteristic (ROC) analysis and kappa statistics. Regarding tumor detection, the image set composed of coronal and sagittal MPR images and of axial images obtained in all phases had a significantly higher value for the area under the ROC curve (A(Z), 0.98 +/- 0.01) than the other image sets and yielded the highest sensitivity (93.5%). The sensitivity of the arterial phase image set (80.6%) was significantly lower than that of all other image sets. Whereas the image set composed of coronal and sagittal MPR images and axial images obtained in all phases yielded the highest kappa values for all local extension factors evaluated, the image set composed of only arterial phase images yielded the lowest kappa values for almost all of the factors. A combination of pancreatic parenchymal phase and PVP imaging is necessary and efficient for the assessment of pancreatic adenocarcinoma. The addition of coronal and sagittal MPR images increased the performance of MDCT, especially in the evaluation of local extension.

The value of multi-direction adjusting multi-planar reformation in displaying the ossicles

目的 探讨多向调整多平面重组(MPR)技术全程显示听小骨及其关节的方位和方法.方法对50侧正常中耳行高分辨率CT各向同性扫描后再行多向调整MPR后处理,确定听小骨同层全程显示的基础显示方位、重组基线旋转中心点和旋转方向的定向解剖标志,测量重组基线旋转角度,对听小骨在轴面、冠状面、矢状面及多向调整MPR全程显示位4种方位上的全程显示程度进行分级,做Ridit分析和x2检验.结果多向调整MPR锤骨、砧骨、镫骨的同层全程显示率均为100%(50侧中耳),多向调整MPR对于听小骨全程显示率明显高于轴面(镫骨6侧、锤骨0侧、砧骨0侧)、冠状面(锤骨3侧、镫骨0侧、砧骨0侧)、矢状面(锤骨0侧、砧骨0侧、镫骨0侧),差异有统计学意义(P＜0.01).结论(1)各向同性扫描基础上的多向调整MPR技术提供了具有诊断意义的听小骨全程显示方法,具有重要临床应用价值.(2)只需1次扫描多次MPR后处理,就可取代多次多方位扫描,是听小骨多方位整体观察的必要途径之一。