In situations where treatment overlies a mucous membrane, for example, the nose or mouth, a lead shield should be used to protect the membrane because the mucosa is sensitive to radiation and further, treatment reactions can be severe and painful. For treatment overlying the nostrils, a small piece of lead should be inserted into the nostril to protect the mucosa and nasal septum within the treatment area . Towards the end of treatment, the inside of the nose will become very sore so care should be taken when inserting and removing the lead shield. If necessary, lubricants can be used to assist this procedure. Similarly, when treating areas near the lips, it is advisable to insert a lead shield into the patient’s mouth, between the lips and teeth, to protect the teeth and gums.
In the event the tumour forms a thick scab, it is important to debulk the tumour and remove the scab because it acts as a layer of build up, thus absorbing the photons and therefore preventing the higher energy X-Rays from reaching the tumour . It is important that the patient be advised not to interfere with the lesion and that any debulking be done by the radiographer only. Further, this should be done carefully using aseptic techniques, for example, by thoroughly cleaning the area first before using gloves and sterile tweezers to gently pry away pieces of the scab.
It is common during this debulking process to experience bleeding of the lesion. Following treatment, it can be dressed and cared for according to the recommendations in the patient care section.
It is important to observe the patient closely during treatment because any movement may compromise the treatment being given. Generally, a CCTV system is employed using two independent cameras; one is focused on the patient whilst the other is focused on the end of the applicator.
Due to the nature of low energy X-Rays and their short penetrative distance, it is essential that the end of the applicator be kept in contact with the patient. If there is any movement or the patient pulls away from the applicator, then it is necessary to interrupt the treatment and enter the room to reposition the patient.
The PC driven control system enables the operator to select all relevant treatment parameters, such as the correct filter and applicator and the required beam on time or monitor units as in dose based systems.
The following data is displayed during treatment:
- The actual tube voltage and current or dose rate
- Filter and App selection
- Treatment Exposures:
- The set and administered values are displayed either in time or dose monitor units (system dependent)
- Backup timer
The system can also be purchased with a record and verify system, which enables the patient to be input and verified against on a daily basis to prevent incorrect treatments from being delivered.
It also acts as a verification system, providing interlocks between the system and the selected filters and applicators, thus preventing the X-Rays from being switched on until all recorded parameters are correct.