Multi-Slice Computed Tomography (MSCT)

Indications

Multi-Slice Computed Tomography (MSCT) image analysis included defining the three-dimensional anatomical location of the tumor, and cancerous cell, evaluating the maximum axial diameter, margin fracture, and density of the bony lesions, and assessing associate anatomical relationships of feeding arteries, vessel, capillary, and vertebral artery on the pre-contrast images and contrast-enhanced CT images. It can also help in dissecting vertebra overlapping superior and inferior borders of the spinal tumor, complete, incomplete vertebral fracture, stroke, vascular perforation in the brain, separating and protecting peripheral vessels around the tumor, as well as a resecting tumor for revealing intratumoral vessels to achieve maximal resection 3D image of the tumor and minimal damage to the spinal cord.

Thoraco‐abdominal aorta

• Diagnosis of congenital and degenerative aortic diseases
• Assessment of acute aortic injuries and dissections
• Evaluation of visceral arteries (coeliac, superior mesenteric, and renal arteries)
• Preoperative planning and follow up
• Tumor staging and surgical planning

Renal arteries

• Assessment of anatomy for donor transplants
• Diagnosis of renal artery stenosis in hypertensives or deteriorating renal function
• Assessment of renal arteries post‐intervention (renal artery stenting)

Peripheral arterial system

• Assessment of peripheral vascular disease
• Assessment of bypass grafts

Carotid/intracranial circulation

• Characterization of the atherosclerotic disease
• Assessment of aortic arch vessels
• Verification of internal carotid artery stenosis
• Preoperative planning of endovascular and surgical treatment of intracranial aneurysms and vascular malformations

Cardiac imaging

• Atypical chest pain
• Patients with intermediate-risk
• Young patients with a high risk for coronary disease
• Coronary artery anomalies
• Non‐invasive follow‐up following percutaneous transluminal angioplasty and stenting
• Assessment of myocardial scars, aneurysms, tumors, and thrombi
• Assessment of coronary artery bypass grafts
• Assessment of the pulmonary veins before and following radiofrequency ablation
• the diagnostic accuracy of coronary artery disease; the prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques.

Bone and spine

• Intraspinal or intervertebral foramen cervical dumbbell tumors,
• tumors beyond the intervertebral foramen
• Spinous process, supraspinal and interspinous ligament,
• The contralateral paravertebral muscle thus
• Investigate stability and flexibility problems of cervical vertebrae and
• alleviates cervical stiffness.
• Reveals the contour of the tumor as well as compression upon the spinal cord, the extent of spinal edema as well as mutual relationships among the tumor, dura mater, and nerve root [rx,rx].
• At the same time, VRT is conducive to analyzing tumors at different levels for intratumoral vascular route and evaluating infliction and erosion extent of vessels thus assessing neurosurgical difficulties and risks.
• Owing to its high resolution based on the reconstruction thickness at the sub-millimeter level,
• VRT formulates images from different perspectives for locating vertebral artery, confirming vascular route and compression degree as well as visualizing peripheral vessels around the tumor.
• sparing nerve roots: nerve roots above the tumor or enwrapped by the tumor could be dissected and protected, while nerve roots coursing through the tumor should be resected due to their involvement in the tumor original.

Analysis of coronary artery lesions

Systematic analyses of a coronary artery MDCT study took into consideration the following steps:

• (1) Analysis of images reconstructed from different phases of the cardiac cycle, in order to choose those where the coronary arterial tree is best filled with contrast and where movement artifacts are the least.
• (2) A complete review of axial images that constitute the cardiac volume, paying attention to cardiac anatomy, degree of opacification of chamber and walls of the heart, and aspect of extracardiac structures.
• (3) Optimization of images aimed to improve the visualization of coronary arteries, by using specific post-processing protocols.
• (4) Analysis of the coronary artery tree, for which is fundamental the following systematization:
• □ Examination of the anatomical distribution of coronary arteries aimed to identify normal variants and congenital abnormalities of the origin of vessels.
  □ Detection and localization of coronary artery lesions, carefully avoiding sections and angulations or interposed structures with potential image artifacts.
• □ Evaluation of composition and morphology of the lesion. In regard to the composition of the plaque, a distinction was made between calcified and non-calcified plaques. Plaques with a mean attenuation of 130 HU or greater were graded as calcified, whereas plaques with a mean attenuation of less than 130 HU were graded as non-calcified. Calcified plaques were identified on nonenhanced scans, and non-calcified plaques were identified on contrast-enhanced scans.
• □ Qualitative and quantitative assessment of obstruction of the vessel caused by the lesion.

A classification of atherosclerotic coronary artery lesions is possible by applying this systematic analysis of MDCT. This classification can be made according to the following aspects:

• The number of vessels involved.

□ The location: proximal, middle, or distal portions of the vessel.

□ The extension of the lesion: focal or diffuse.

□ The degree of obstruction.

a. Non-significant stenosis (less than 60 % of the vessel lumen, including mild and moderate degrees of obstruction).

b. Significant stenosis (equal or more than 60 %, including critical subocclusive and occlusive lesions.

□ The components of the lesion:

a. Non-calcified, mixed, or “soft” lesions.

b. Calcified lesions: The calcium component of the lesion can be focal, diffuse, eccentric or concentric.

Currently, MSCTA has been applied for late-phase image reconstruction in the following ways [rx] multiplanar reconstruction (MPR), shaded surface display (SSD), bone scintigraphy, maximum intensity projection (MIP), and recently volume rendering technique (VRT) which surpass its predecessors as a supreme technique in reconstructing three-dimensional spatial relationships.

Side Effects

Potential adverse effects of contrast medium injection and radiation exposure side effects were explained to all the patients by a radiologist, and written informed consent was obtained before the procedure.