Particularly, but not exclusively, the apparatus is intended for use in ultrasound examinations of lower limbs.

Lower limb venous disorders are typically examined by medical professionals by use of ultrasound scans. A prevalent form of venous disorder is varicose veins, in which faulty valves in blood vessels within the limb allow blood to flow back past the valve. This can lead to weakening of the veins, unsightly scarring and bulging of the limb, pain, numbness, and even inability to move the limb. Other venous disorders which may be identified by means of ultrasound scanning include deep vein thrombosis.

It is therefore desirable to identify possible disorders early in their progression, and to be able to identify the location within the limb of the faulty valve.

To achieve this, the medical professional typically makes use of ultrasound scanning procedures. However, such procedures can be complex and uncomfortable to perform, particularly when the lower limb is involved. It is often desirable to examine the limb in an extended position, and with as little as possible of the patient's weight borne thereon. Typically, therefore, the patient is examined while lying on a hospital bed, with the lower limbs extended. Given the complex topography of the circulatory system, it is necessary for the patient to be moved a number of times during examination to allow sufficient

access to all areas of the limb. This can be a particular difficulty when patients are old or infirm, while interrupting the scanning to allow the patient to be moved can result in the sonographer finding difficulty in following the course of a single blood vessel along the limb.

Further, to achieve inspection of the lower calf, the patient may be required to sit upright, such that the limb is vertical to ensure adequate blood circulation. This again requires the patient to move or to be moved, and further increases the complexity and time taken by the procedure.

Due to these difficulties, and to the awkward positions necessary for a sonographer to adopt while scanning patients, it is believed that medical professionals involved in this field may have an increased likelihood of experiencing certain health problems; for example, strain injuries, musculoskeletal problems, backache, and the like. Such difficulties reduce efficiency, increase time lost due to illness, and can result in costly medical bills for the professional's employer, not to mention the pain and discomfort suffered by the professional.

Specialist equipment for supporting patients during examination is known ; however, these items of equipment are typically relatively large, heavy, and costly, which factors mitigate against their widespread adoption.

Further, they do little to reduce the time necessary for

conducting an examination of a patient.

It is among the objects of embodiments of the present invention to obviate or alleviate these and other disadvantages of known patient support mechanisms.

According to a first aspect of the present invention, there is provided patient support apparatus for use in lower limb examinations, the apparatus comprising patient support means for supporting a patient in an upright position, and foot support means for supporting a patient's foot in a raised position, such that the patient's weight in use is substantially borne by the patient support means and the patient's other foot.

The present invention thus allows a patient to be supported in an upright position while being examined, so allowing a sonographer to access all parts of the lower limb without requiring patient movement. The foot support means raises the foot of the limb under examination, thereby causing the patient to bear their weight on the other foot, so relaxing the limb under examination and reducing the likelihood of circulatory artefacts which may obscure the results of the examination. Since the patient may remain standing throughout the examination, and does not need to move or be moved, the time taken to perform the examination may be reduced.

Preferably the patient support means is arranged to support a dorsal region of a patient. That is, the support means may for example support a portion of a patient's back or buttocks, or both. This arrangement provides a

comfortable support position for a patient.

Preferably the foot support means is located such that a lower calf of a limb supported thereon is in a substantially vertical orientation. This improves the efficiency of the examination procedure.

Preferably the patient support means comprises a substantially vertical column or the like. The patient may thus lean against this column, allowing the column to take some portion of the patient's weight. Use of a column, pillar, post or the like also minimises obstruction of the patient by the support means, so allowing the sonographer a greater degree of access to the patient than otherwise.

The support means may further comprise a backrest, preferably a padded or otherwise cushioned backrest, for the patient to lean against. The backrest is preferably mounted on the column. Preferably the backrest is angled at around 10 degrees to the vertical ; this has been found to improve patient posture when leaning against the patient support means.

The patient support means may comprise seating means.

Preferably the seating means does not provide complete support for the patient, but causes the patient to adopt a position such that some of the patient's weight must be borne by the patient's limbs. Conveniently, therefore, the seating means is in the form of an angled support, such as a platform. It has been found that an angle of around 40 degrees below the horizontal provides a suitable arrangement. Alternatively, the seating means may comprise

a rounded surface, a horizontal bar or perch, or the like.

Preferably the seating means is cushioned or otherwise padded. Preferably the seating means comprises a pair of supports, each of which may be independently movable to allow support of many different patient shapes. Use of spaced paired supports allows the sonographer relatively ready access to the inner thigh area without having to move the patient.

The patient support means in preferred embodiments of the invention comprises both a seating means and a substantially vertical column, as described above. This allows for improved patient comfort. Preferably the seating means is mounted on the column.

Preferably the patient support means is adjustable, to accommodate variations in patient build. Conveniently the support means is height adjustable. Where the support means comprises both a backrest and a seating means, these are preferably independently adjustable. Conveniently, the backrest and seating means are independently movably mounted on a vertical column; for example, on independent tracks provided on or within the column. The support means may be manually adjustable, or may be electrically, pneumatically, hydraulically, or mechanically adjustable.

In selected embodiments of the invention, the support means includes a manually-driven crank means operably connected to a track along which the seating means runs within the column.

Preferably the foot support means is movable, to allow

for variations in patient shape, size, and position.

Conveniently the foot support means is arranged to run in a track or the like, limiting the freedom of movement of the foot support means. The track is conveniently in the form of an arc of a circle. The apparatus may further comprise locking means for selectively preventing movement of the foot support means ; for example, the foot support means may be spring-mounted in a track such that movement of the support means is only possible when the foot support means is depressed. Alternatively a latch, bolt, or other locking means may be used.

Preferably the foot support means includes an uneven surface on which a patient's foot may rest. This makes it uncomfortable for the patient to put much of their weight on the foot support means, so preventing the patient from doing so. Conveniently the uneven surface is a curved surface; for example, the foot support means may be in the form of a dome or similar shape. It has been found that a dome with walls rising at. around 10 degrees to the horizontal provides a convenient form of the foot support means.

Preferably the foot support means comprises retaining means for retaining a patient's foot thereon. For example, the foot support means may include a portion for receiving a heel of a foot therein; this may be in the form of a loop extending rearwardly from the foot support means.

Alternatively, the retaining means may provide a portion against which a patient's toes may rest; or a foot strap,

buckle, or the like. Conveniently the retaining means is cushioned or otherwise padded, for improved patient comfort.

Preferably the apparatus further comprises arm rests for the patient. These allow the patient to take some of their weight through their arms, rather than all through the patient's unsupported limb and the patient support means. This is of assistance particularly to infirm patients who may be unable to stand unaided for long periods. The arm rests are preferably mounted to the patient support means, although they may alternatively be free-standing. Preferably the arm rests include patient grip portions, to allow a patient to comfortably grip the arm rests. For example, the arm rests may be covered with an elastomer or the like.

The apparatus may be mounted on a platform. This allows the patient to be raised relative to the sonographer, so reducing the likelihood of discomfort and possible injury to the sonographer during examination. The platform is preferably vertically movable, to allow the height of the platform to be adjusted so as to accommodate variations in patient and sonographer height. The platform may thus include a hydraulic, electric, or pneumatic mechanism to allow adjustment of the platform height.

Provision of such a mechanism in the platform has the further advantage of providing a weight to stabilize the platform against the weight of a patient resting against the patient support means. The platform may also be movable

to allow the apparatus to be transported from place to place. Conveniently the platform includes wheels, castors, or the like; preferably these are selectively lockable to prevent unwanted movement. Preferably the platform is rotatable, to allow a sonographer ready access to the patient from any angle.

These and other aspects of the invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a patient support apparatus in accordance with an embodiment of the present invention; Figure 2 shows a side view of the apparatus of Figure 1, illustrating the position of a sonographer using the apparatus; and Figure 3 shows a plan view of the apparatus of Figure 1.

Referring to the Figures, these show an apparatus 10 for supporting a patient during an ultrasonic examination of the lower limbs. The apparatus 10 includes a patient support in the form of a vertical column 12, on which are mounted a padded backrest 14, and a pair of padded seat cushions 16. As can be most clearly seen in Figure 2, the backrest 14 is angled at around 10 degrees to the vertical, while the seat cushions 16 are angled at around 40 degrees below the horizontal, and 12 degrees inward tilt. The cushions 16 are independently taillable to a limited extent, to allow for movement to support patients of differing

builds. The column 12 is mounted on a platform, which is itself mounted on lockable castors (not shown). Also mounted on the platform 18, and to the column 12, are a pair of armrests 20, portions of which are covered with Santoprene (RTM) elastomeric sleeves 22.

On the platform 18 is mounted a foot support 24 in the form of a dome, carrying a rearwardly-extending heel rest 26. The rear of the foot support 24 is slightly higher than the front, for a more relaxed and slightly bent patient limb. The foot support 24 is mounted within an arc-shaped track 28 (Figure 3), and is spring-biassed against the platform 18 such that compression of the spring by applying force to the foot support 24 allows the support 24 to be moved along the track 28.

Provided on the rear of the vertical column 12 is a winding handle 30 which is connected to a mechanism within the column 12 to which the seat cushions 16 are mounted.

Turning of the handle 30 raises and lowers the seat cushions 16 to allow for adjustment to suit patients of different heights. Similarly, the backrest 14 is provided with an adjustment mechanism to allow its vertical position on the column 12 to be altered.

In use, the apparatus 10 performs as follows. The platform 18 is first of all lowered, to allow a patient to step onto the platform. The patient then seats themselves on the seat cushions 16, while leaning against the backrest 14. These are arranged such that a portion of the patient's weight is supported via the column 12, while a portion of

the weight must be supported by the patient themselves, through their lower limbs. Patients who are unable to support much weight through their limbs may grasp the armrests 22 to provide further support.

Once the patient is comfortably supported, the operator of the apparatus raises the platform 18 to a comfortable operating height. The operator then moves the foot support 24 to an appropriate position for the first limb to be examined, and places the patient's foot thereon.

The dome shape of the support prevents the patient from placing much weight on the foot resting on the support 24, while the heel rest 26 retains the patient's foot in a relatively forward position to ensure the foot cannot be placed flat. The patient's other foot remains flat on the platform 18, supporting the patient's weight which is not taken by the column 12 or armrests 20. The patient thus has the limb to be examined in a substantially vertical alignment with little or no weight borne thereon.

The operator then performs an ultrasound scan on the limb to be examined. The nature of the column 12 and seat cushions 16 mean that the operator can access all parts of the limb without requiring the patient to move, so reducing examination time. When examination of the first limb has finished, the operator may switch examination to the second limb if necessary, by moving the foot support 24 along the track 28 to a suitable position.

It can be seen that the present invention thus provides a patient support apparatus which may be used for

ultrasound examinations of lower limbs with the patient remaining upright and in a single position throughout the examination, thereby reducing the duration of such examinations. Further, the support holds the patient in a convenient position for the operator, so reducing the risk of the operator suffering strain injuries.