The city has got an MRI machine with an audio-visual entertainment option that offers the distraction patients undergoing the scan badly need to fight off claustrophobia.

Doctors say one in every 10 patients feels claustrophobic while lying still for a prolonged period in the narrow tunnel during an MRI (magnetic resonance imaging) scan.

Claustrophobia often causes patients to fidget, resulting in the procedure being stopped midway.

In the Rs 7.5-crore machine - installed at AMRI Hospitals, Mukundapur - an audio-visual presentation starts as soon as the "patient table" slides into the scanner tunnel.

The images will play out on the wall at the rear and the patient will see the reflection in a mirror that will hang from the roof of the tunnel in front of her/him.

To hear the soundtrack, the patient has to use earphones. The audio will help drown out the loud noise emitted by the machine during the scan.

As part of the "In-bore Experience", a patient can watch an animation or the enchanting Alps or the serene aquatic life while the scan is on. An MRI scan lasts 15 minutes to an hour.

"Everyday, patients undergoing the MRI scan complain of claustrophobia, anxiety and emotional distress," said Manash Saha, director and head, imaging and interventional radiology, AMRI Hospitals, Mukundapur.

"There is a switch in the tunnel that a patient can press to bail out of the process. Many press the switch, aborting the scan. Since the introduction of the In-bore Experience, few patients are opting for the bail-out."

In an attempt to prevent an attack of claustrophobia, some hospitals in the city, such as Woodlands, have installed open-bore MRI machines, in which the patient's head remains outside the tunnel.

Others, such as Medica Superspecialty Hospital, provide earphones to patients to listen to music during the imaging.

Psychiatrists said an MRI scan could be traumatic for patients with a tendency to be claustrophobic. "They feel the walls are collapsing on them and they will be crushed to death," psychiatrist Ranadip Ghosh Roy said. Some of these patients need counselling before going through the process.

The in-tunnel experience can be unsettling even for patients who are not claustrophobic.

Subir Ganguly, the head of radiology at RG Kar Medical College and Hospital, said the scan had to be often stopped midway as patients got scared. "The heart rate goes up, people start sweating and fidgeting once the machine closes in on them. Also, the high-pitched sound emanating from the scanner cause problems," Ganguly said.

Doctors said the open-bore technique did not produce good results if the machine was old and its magnetic field not powerful enough.

CT scan

The AMRI Hospitals in Mukundapur and Salt Lake have recently installed HD CT scan machines that emit 60 per cent less radiation and does not require children to be sedated during the process.