GB2216012A

GB2216012A - Irradiation reducing devices

Info

Publication number: GB2216012A
Application number: GB8903605A
Authority: GB
Inventors: R John Ives Cater; Michael Timothy Tobert; R David Andrew Whiten
Original assignee: University of St Andrews
Current assignee: University of St Andrews
Priority date: 1988-02-17
Filing date: 1989-02-16
Publication date: 1989-10-04
Also published as: GB8903605D0; GB8803676D0

Abstract

Devices which reduce or prevent damaging radiation from an irradiation source (1) from impinging on selected areas of a patient's body e.g. the eyes comprise means for retaining (22, 23) the patient and filtering (21) out the undesirable radiation. In another embodiment monitoring means on or near the patient detects the radiation and by controlling a positioning means helps to prevent the radiation from impinging on the part of the body that it could damage. <IMAGE>

Description

IRRADIATION REDUCING DEVICES This invention relates to devices which reduce the irradiation of radiation therapy treatment reaching the eyes of a patient, for example young babies, from a radiation source. The devices disclosed in this invention may be equally applicable to the treatment by irradiation of patients suffering from a number of diseases including jaundice.

Young babies suffering from jaundice are routinely treated by phototherapy. The phototherapy, from a light source emitting blue and white light, acts to break down the bilirubin in the baby's skin which give it the yellow tinge characteristic of jaundice. The baby is usually subjected to the phototherapy treatment whilst it is lying in a bassinet which is typically made of transparent plastic. Eyepads are placed over the eyes of the baby being treated in order to prevent their retinas being damaged by the phototherapy treatment, the eyepads being retained by netting and bandages. Furthermore because the baby is naked in the bassinet, to allow the phototherapy treatment to affect the whole body surface, a transparent cover is frequently fitted over the whole of the bassinet. This transparent cover may also act as a heat shield.The combination of unsightly and uncomfortable eyepads, which the babies scratch resulting in mittens being applied to their hands, and the transparent cover which isolates the baby from its parents, causes distress both to the baby and its parents and may thus reduce the time that the baby is exposed to the phototherapy treatment.

It is an object of the present invention to provide devices which reduce the irradiation from the phototherapy treatment from reaching the eyes of the baby without the need for the baby to wear eyepads or to be covered by transparent covers which isolate the baby from its parents, thus reducing the distress experienced by the baby and its parents thereby increasing the length of time that the baby is exposed to the phototherapy treatment.

Accordingly, the present invention provides a device for reducing the irradiation reaching the eyes of a patient from a radiation source characterized in that said device comprises a filter and a retaining means, the filter being supported in a position intermediate the patient's head and the radiation source to reduce irradiation reaching the patient's eyes while leaving the patient's trunk and limbs exposed thereto and said retaining means being adapted to keep the patient 5 head in the area where the irradiation from the radiation source is reduced by the filter.

From another aspect, the invention provides a crevice for reducing the irradiation reaching the eyes of a patient from a radiation source, comprising monitor means operative to monitor the patient's position relative to the radiation source, means for positioning the beam of irradiation from the radiation source under the control of the monitor means so as to shade the patient's head Trom the irraciation of the radiation source while exposing the patient's trunk and limbs thereto.

The filter disclosed in this invention can be made from a number of materials including for example amber coloured perspex or may be made from a material totally opaque to the irradiation from the radiation source. It will be appreciated, by a person skilled in the art, that the filter may be made from a material which reduces or is opaque to that part of the irradiation which it is desired to prevent from reaching the patient's eyes.

The retaining means of this invention can include for example, shaped foam blocks, pillows and cushions or may also include for example straps or other suitable retaining means.

The monitor means disclosed in this invention include monitors, adapted to be placed on the baby, which can detect the irradiation from the radiation source and can transmit a signal to the means for positioning the beam of irradiation from the radiation source.

Suitable monitor means include for example active monitor means such as for example photoelectric cells or other irradiation detecting devices which will detect all or part of the irradiation from the radiation source.

Other suitable monitor means are passive monitor means which include for example materials, which when attached to the patient will reflect irradiation from the radiation source to for example a further sensor associated with the positioning means.

In a preferred embodiment the monitor means will proue a signal when irradiated by the radiation source, the signal being transmitted by known conventional means to the positioning means to effect a change therein such that the irradiation is removed from the monitor means and hence from the part of the patient adjacent the monitor means.

It will be appreciated that whilst the monitor means is preferably attached to the patient they may also be placed in an appropriate place beside the patient.

The means for positioning the beam of irradiation from the radiation source include for example shields around the radiation source which give a tight, well defined beam or irradiation and a motor, controlled by the monitor means to move the radiation source so that the irradiation does not reach for example the eyes of the patient.

In further embodiments the positioning means can include for example focusing means, for expanding or contracting the width of the beam of irradiation, and shutters, which can be movable, so arranged as to interrupt the beam of irradiation when moved.

It will be appreciated that the devices of the present invention may be used for a variety of medical purposes and for use in the treatment by a number of different radiation sources.

The invention will now be described by way of example only, with reference to the accompanying drawings of which: Figure 1 is a schematic representation of the present known equipment used to prevent irradiation from a radiation source from reaching the eyes of a baby; Figure 2 is a schematic representation of a device according to the invention which incorporates a filter and retaining means; Figure 3 is a schematic representation of a device according to this invention whizz incorporates a monitor means and a means for postiioning the beam of irradiation from the radiation source.

Referring now to Figure 1, the radiation source 1, in this embodiment a series of fluorescent tubes, irradiates the patient 2 in this case a baby whose eyes and head are covered by eyepads and netting 3. The baby 2 lies in a bassinet 4 which has a heat shield cover 5 placed over the top of the whole cot 4.

Figure 2 shows an embodiment of the invention in whicn the radiation source 1 is placed above the bassinet 4 containing the baby 2 which has no eyepads on its eyes, being protected from the irradiation of the radiation source 1 by a filter 21. Optionally the filter 21 may be hinged, (not shown) to allow easy access to the patient. The eyes of the baby are kept in the area where the irradiation is reduced by the filter by retaining means 22 and 23 which prevent the baby from moving up and down the cot. A clamp (not shown) may be used to fix the radiation source 1 relative to the bassinet 4 so that neither can move relative to each other.

Figure 3 shows another embodiment of the invention in which the radiation source 1 is a single bulb irradiating the baby 2 lying in the bassinet 4. The monitor means 31, and 32, consists of a marker 31 for example a reflective disc, placed on the baby below the eyes, and a detector 32, for example a photoelectric cell which detects the position of the marker 31 and moves the shutter 33 (positioning means) in the direction of Arrow A so as to cut out the irradiation that would otherwise fall on the eyes of the baby. For example, the detector 32 may be responsive to the brightness of the marker 31, and thus act to detect when the marker 31 is illuminated by the radiation source 1.

Claims

1. A device for reducing the irradiation reaching the eyes of a patient from a radiation source characterised in that said-device comprises a filter and a retaining means, the filter being supported in a position intermediate the patient's head and the radiation source to reduce irradiation reaching the patient's eyes while leaving the patient's trunk and limbs exposed thereto and said retaining means being adapted to keep the patient's head in the area where the irradiation from the radiation source is reduced by the filter.

2. A device as claimed in claim 1 wherein the ssìd filter is made from an amber coloured material.

3. A device as claimed in any preceeding claim in which the said retaining means comprise two members, one placed at the patient's head and one at the patient'.# feet in order t help prevent movement of the patient.

4. A device for reducing the irradiation reaching tr eyes of a patient from a radiation source comprising means operative to monitor the patient's position relative to the radiation source, means for positioning the beam of irradiation from the radiation source under the control of the monitor means so as to shade the patient's head from the irradiation of the radiation source while exposing the patient's trunk and limbs thereto.

5. A device as claimed in claim 4 wherein the monitor means comprises a first sensor means which is capable of detecting irradiation from the radiation source.

6. A device as claimed in claims 4 or 5 in which the monitor means comprises a photoelectric cell, which can detect visible light, which may be attached to the patient.

7. A device as claimed in claims 4,5, or 6 in which the monitor means comprises a reflecting member adapted to be attached to the patient and a second sensor means which responds to irradiation reflected from the said reflecting member and thus control the positioning means.

8. A device as claimed in any of claims 4,5,6 or 7 in which the positioning means comprises a focusing means whereby the irradiation from the radiation source is focused as necessary to avoid impinging on the monitor means.

9. A device as claimed in any of claims 4,5,6,7 or 8 in which the positioning means comprises a movable member, essentially opaque to the irradiation, placed between the patient and the irradiation source

10. A device as claimed in any of claims 4,5,6,7,8 or 9 in which the positioning means comprises a means for moving the radiation source, and thus the irradiation, relative to the patient.

11. A device as substantially hereinbefore described with reference to the accompanying drawings 2 or 3.