Monitoring blood pressure at home is recommended by the American Heart Association for the estimated 74.5 million American adults suffering from hypertension. CalHealth has created a blood pressure monitor that's housed in a computer mouse. After a user pushes a finger into the cuff monitor, the device sends readings to software on a PC for analysis, or to send on to doctors via email.

CalHealth's MDMouse is a fully functional USB optical mouse with a sphygmomanometer payload. The blood pressure meter extends on a rotating arm out of the body of the mouse. The user inserts a finger, and an air pump expands an air bag inside the tube around the digit. A pressure sensor stops the pump when it detects that the right amount of pressure has been applied and the user sets the monitoring to start via the computer software.

The pressure on the finger is initially increased beyond cutoff and then slowly decreased until arterial vessel pulsation is detected. CalHealth says that "the corresponding cuff pressure at this point will be substantially equal to systolic blood pressure which is the pressure when the heart is pumping."

The decrease of pressure continues until the device no longer registers arterial pulsation where, according to the company, "the pressure of the cuff at this point will be substantially equal to diastolic blood pressure."

The readings are then interpreted by the software and displayed for the user. The software can also store data from previous tests and present the user with graphs for onward email transmission to medical personnel.

There's a release valve to let the air out after each test, so there's no fear of the experience turning into some Jigsaw nightmare where the device starts to menacingly crush the trapped finger.

However, there has been some doubt cast on the accuracy of finger-based monitors. The American Heart Association recommends an automatic, cuff-style, upper-arm monitor: "Wrist and finger monitors are not recommended because they yield less reliable readings."

Any home monitoring device should be checked for accuracy by medical practitioners.

There's no word on price or availability at the moment, but updates will be posted on the MDMouse website.