War of words over Cruise's ultrasound 

Movie icon Tom Cruise is at the centre of a fresh medical row with experts expressing concern over his purchase of a sonogram machine to perform at-home scans on expectant fiancee Katie Holmes.

Cruise told US television interviewer Barbara Walters last month that he had bought an ultrasound machine to peek at the foetus of his unborn baby with the Batman Begins actress who he has been dating since April.

But medical experts are warning it is dangerous for untrained Cruise and Holmes to be operating a complex piece of medical equipment such as an ultrasound machine at home.

Both the The Society of Diagnostic Medical Sonography (SDMS) and the American College of Radiology (ACR) are up in arms at the Mission Impossible and Top Gun star's admission that he bought the machine that can cost anywhere between $20 000 and $280,000.

"The Society is concerned about the safety of Cruise's decision to purchase a medical device and perform a medical diagnostic procedure without appropriate training," the SDMS said in a statement.

"Diagnostic medical sonographers complete educational programs and take national certification examinations to ensure they can perform sonograms safely and in a manner that obtains accurate results," it added.

The SDMS said use of such a machine required knowledge, hand-eye coordination and pattern recognition and that "reading the manufacturer's manual or having a one hour orientation is not sufficient".

The ACR issued a similar warning, saying the famous couple could potentially harm their unborn baby by performing ultrasounds without a doctor's supervision.

"This is a patient safety issue. Untrained people, even if they have the financial means, should not buy, or be allowed to buy and operate, ultrasound machines which are, in fact, medical devices and should not be used without a medical indication," said Dr Carol Rumack of the ACR's Ultrasound Commission.

The medical broohaha is the second that 43-year-old Cruise has become embroiled in this year following a clash with psychiatrists over his opposition to their science.

The American Psychiatric Association (APA) slammed Cruise for referring to psychiatry as a "pseudoscience", while he got into a public row with actress Brooke Shields after he criticised her use of drugs to treat postnatal depression.

"It is irresponsible for Mr Cruise to use his movie publicity tour to promote his own ideological views and deter people with mental illness from getting the care they need," said APA president Dr Steven Sharfstein in June.

Cruise is an ardent member of the Church Scientology that dismisses the use of psychiatry and psychotropic and anti-depressant drugs.