Early experience with surgically inaccessible wide-necked intracranial aneurysm embolised with Guglielmi Electrically Detachable coils and electrothrombosis.

We describe our early successful experience with Guglielmi Electrically Detachable Coils (GDC) and electrothrombosis in treating a surgically inaccessible wide-necked intracranial aneurysm in a Chinese patient. The precautions taken to prevent unnecessary complications while performing this technique was also described. It provides a serious alternative to other less ideal types of embolising agents and direct surgery in treating patients with these difficult-to-treat aneurysms.

Bladder dose estimation during intracavitary brachytherapy for carcinoma of the cervix using a single line source system.

The estimation of maximum bladder doses from orthogonal radiographs is unreliable when triple source systems are used for intracavitary brachytherapy (BT) for gynaecological cancers. For single line source systems, the estimation of maximum bladder doses from radiographs should be more reliable due to the radial symmetry of the isodose distribution. A pilot study has been carried out to compare the estimated maximum bladder doses from standard radiographs with data obtained from CT for single line source BT treatments.

The influence of air cavities on the optic chiasm dose during pituitary radiotherapy for acromegaly.

The treatment planning of acromegalic patients can be complicated by the presence of abnormally large frontal air sinuses which allow increased anterior beam transmission causing increased dose to the optic nerve and chiasm which, if excessive, can result in blindness. This potential problem has been investigated by computer treatment planning exercises which have allowed for a variable thickness (1-3 cm) of air cavity beneath the frontal field and for different weightings of the lateral opposed fields relative to the anterior field. The resultant overdosage can be greater than 5% of the intended dose.

Treatment of carcinomas of the uterine cervix which remain bulky after initial external beam radiotherapy: a pilot study using integrated cytotoxic chemotherapy prior to brachytherapy.

The use of cytotoxic chemotherapy (CT) between external beam radiotherapy (EBRT) and intracavitary brachytherapy (BT) in patients with bulky carcinomas of the uterine cervix which regress poorly after initial EBRT has been evaluated in a pilot study. The aim of CT was to limit tumour clonogen repopulation while awaiting further tumour regression in order to improve the BT dose distribution. Between 1989 and 1992, 22 patients with FIGO Stage IIA, IIB and IIIB cervical carcinomas were given two to three cycles of cisplatin-based CT between EBRT and intracavitary BT.

Case report: low dose rate and high dose rate intracavitary brachytherapy in a patient with carcinoma of the cervix.

The role of low dose rate (LDR) intracavitary radiotherapy in the management of carcinoma of the uterine cervix is well established. However, there are selected groups of patients in whom high dose rate (HDR) intracavitary radiotherapy may have particular advantages. A case report of a patient with carcinoma of the cervix who received both LDR and HDR intracavitary radiotherapy is presented.

National Patient Master Index in Singapore.

It has been the practice of hospitals and medical institutions to keep their patients' medical records. Access to such valuable information will be confined within the respective health institutions if there is no proper infrastructure to facilitate sharing of the information. On the other hand, it has been the wish of medical professionals, as well as patients who frequent hospitals and medical institutions that patients' medical records, especially essential medical conditions, are readily available, whenever required, regardless of the health institution by which the patient is being attended to.

The achievement of isoeffective bronchial mucosal dose during endobronchial brachytherapy.

Purpose: The use of endobronchial brachytherapy in the treatment of lung cancer is increasing due to the more widespread availability of high dose rate afterloading equipment. The complications include small airway (segmental and small lobar bronchi) fibrosis, stenosis, and obstructive complications in addition to hemorrhage. A progressive reduction in the diameter of the bronchial lumen occurs at each division of the bronchial tree.

Derivation of the optimum dose per fraction from the linear quadratic model.

The linear quadratic equation for fractionated radiotherapy has already been adapted to include a time factor for tumour repopulation: loge cell kill (E) is given as a function of dose per fraction (d), number of fractions (n), overall treatment time (T) and the clonogen doubling time (Tp). By incorporating a normal tissue isoeffect and replacing the relationship between T and n by a function f, the equation for E can be rewritten as a more complex function of d. In this form, E and d are continuous variables so that the dose per fraction (d') required to produce maximum values of E for isoeffective late normal tissue effects can be found by differential calculus.

Non-uniform dwell times in line source high dose rate brachytherapy: physical and radiobiological considerations.

The ability to vary source dwell times in high dose rate (HDR) brachytherapy allows for the use of non-uniform dwell times along a line source. This may have advantages in the radical treatment of tumours depending on individual tumour geometry. This study investigates the potential improvements in local tumour control relative to adjacent normal tissue isoeffects when intratumour source dwell times are increased along the central portion of a line source (technique A) in radiotherapy schedules which include a relatively small component of HDR brachytherapy.

Results of a questionnaire regarding the practice of radiotherapy for carcinoma of the cervix in the UK.

A questionnaire was sent to 50 departments of clinical oncology in the UK in September 1991. The aim was to determine the range of external beam and brachytherapy techniques employed at that time in the radical treatment of carcinoma of the cervix. Replies were received from 35 centres.

A mathematical model of intraluminal and intracavitary brachytherapy.

The adaptation of the linear-quadratic model to allow for the effect of tumour regression and clonogen repopulation between initial teletherapy and subsequent brachytherapy has been extended to include the geometrical conditions encountered in intraluminal and intracavitary brachytherapy. For a radiation line source placed at the centre of a lumen or cavity, regression of any endoluminal tumour towards its mural origin will not result in any change in the minimum brachytherapy-tumour dose with time. In contrast, regression of transmural tumour will cause a potentially advantageous increase in the minimum brachytherapy-tumour dose with time.

The effect of bruised beef addition on the quality of processed meat products.

The aim of this study was to determine the levels of bruised beef that could be incorporated into processed meat products without detrimental effects on product quality. Bruised beef was incorporated into fresh sausages, Devon and semi-dry salami, and compared to products containing unbruised beef. Up to 30%, 25% and 65% of the unbruised beef in fresh sausages, Devon and semidry salami respectively can be replaced with bruised beef with no detrimental effect on product quality (as assessed by a sensory panel), either initially or over the shelf-life of the product at 4°C.

Ministry of Health computerisation programme.

The purpose of the paper is to give the readers an idea of the state of computerisation in the Ministry of Health, Singapore and to highlight some of the benefits of computerisation. The Ministry employs a wide range of computer systems from portable microcomputers, point-of-sale microcomputers, supermicros, minicomputers to mainframe computer. What are the roles of these computers? Why and how are they interconnected? Carry on reading if these questions are appealing to you.

Between-technician variation in the measurement of spirometry with air and helium.

A study using a two-period cross-over design was conducted to determine the between-technician variation in the measurement of variables derived from spirograms with subjects breathing room air and also breathing a mixture of 80% helium and 20% oxygen (He-O2). Twenty-four subjects were allocated systematically into three 2-period cross-over studies (blocks) of 8 subjects each (4 in each sequence in each block). There were 3 technicians in the study, and the subjects in each block were tested by a pair of technicians.