Magnetic Resonance Imaging (MRI) uses a powerful magnetic field and radio waves to generate detailed images of the body’s internal structures. The tight space inside traditional MRI machines often made the experience challenging for some patients. Wide bore technology was developed to address patient discomfort and anxiety by balancing the need for high-quality imaging with a more tolerable experience.
Defining the Wide Bore Design
The term “bore” refers to the diameter of the tunnel the patient slides into during the scan. Traditional narrow bore MRIs typically have an opening of about 60 centimeters (23.6 inches). Wide bore systems increase this diameter significantly, usually featuring a 70-centimeter opening. This additional 10 centimeters provides a noticeably different physical environment.
The wide bore MRI remains a cylindrical, tube-shaped machine, similar to its predecessor. It is still a closed-bore system where the patient is enclosed within the magnet, but the machine is shorter and wider than older models. This design maintains the high magnetic field strength (often 1.5 to 3 Tesla) required for superior image clarity and detail.
Visualizing the Difference: Wide Bore vs. Traditional MRI
From the patient’s perspective, the wide bore machine looks and feels more spacious than a traditional MRI. The increased diameter provides significantly more distance between the patient’s body and the magnet walls, offering more headroom and room around the shoulders and torso.
When lying on the movable scan table, the patient can often see more outside the cylinder, depending on the area being imaged. For lower body scans, such as a knee or foot, the patient’s head and upper chest may remain completely outside the bore. Even when the head must be inside, the wider opening and greater distance to the tunnel ceiling reduce the feeling of being confined.
Enhanced Comfort and Accessibility
The primary benefit of the wide bore design is the reduction of anxiety and claustrophobia. The increased space makes the procedure less stressful for individuals overwhelmed by the narrow confines of traditional systems. This improved comfort allows more patients to complete necessary scans without sedation.
The wider opening and higher weight capacity also significantly improve accessibility. Wide bore systems can often accommodate patients weighing up to 550 pounds, a greater limit than many older machines. The wider design also allows technologists easier access to monitor patients and position equipment more comfortably. Furthermore, the scan table height is often lower on these models, which assists patients with mobility issues.
Wide Bore vs. Open MRI
A common source of confusion is the difference between a wide bore MRI and an open MRI, as they represent distinct technologies. The wide bore MRI is a closed system—a cylindrical tunnel designed to maintain high magnetic field strength. This design ensures the production of high-resolution, detailed images.
In contrast, an Open MRI typically uses a completely different magnet structure, often appearing C-shaped or like two flat plates positioned above and below the patient. While this design offers maximum openness for patients with severe claustrophobia, it often operates at a much lower magnetic field strength, frequently ranging from 0.2 to 1.0 Tesla. This lower field strength can result in longer scan times and potentially less detailed image resolution compared to the high-field wide bore machine.