Overview of radiation dose to patients from medical X-ray examinations in Nigeria.

OBJECTIVES: Medical Imaging accounts for the largest radiation exposure of population from artificial sources of radiation. The radiation dose rcceivedby patients from iedicail x-ray examinations in Nigeria has shown large variations within and among diagnostic centers for similar examinations. This could be traced to lack of imaging protocols and on avalability of local/national diagnostic reference, levels. Hence, the need to assess the trend of radiation doseto patients from radiological practice in Nigeria. Methocls:Entrance surface doses(ESDs) reported by, Nigerian authors for common x-ray examinations from 2000 - 2014 were extracted from articles published in peer reviewed journals, analyzed and compared with ifiternationally recommended Diagnostic Reference Levels (DkLs). RESULTS: Among x-ray examinations, skull accounted for 32% followed by chest (22%), lumbar spine (13%), abdomen (12%), pelvis (8%), extremitics(8%), thorax and cervical spine(5%). The range of mean ESDs reported for various projections of x-ray examination are chest (2.28 - 3.70 mGy); Abdomen (4.42 - 7.22 mGy); Skull (3.81 - 5.19 mGy); Pelvis (5.93 mGy); Lumbar spine (5.73 - 10.98 mGy); Thorax (0.96 - 1.85 mGy); Cervical spine (1.45 - 1.49mGy) and Extremitics (0.31 -0.49 mGy). In this study, it was found that the mean ESDs received by patients from chest, skull and pelvis ex'aminations were higher than the published DRLs for similar x-ray examinations. CONCLUSION: The results of this study showed that to harmonize radiation protection of patients and improve radiological practice in Nigeria there is need for development of comprehensive national diagnostic reference levels.

Radiation therapy interruption in a poor resource setting: causes and management..

BACKGROUND: Treatment interruption is the failure to execute approved treatment plan of a patient. This adversely affects treatment outcomeif not properly managed. This retrospective study causes and management of radiation treatment interruptions during High Dose Rate Brachytherapy(HDRB) for carcinoma of the cervix in a teaching hospital in Nigeria. METHODS: Five hundred patients with cervical carcinoma, who received HDRB, post external beam radiotherapy, between August, 2008 and July, 2013 were assessed. They were grouped into (A): those who experienced treatment interruption and (B): those who did not. Each patient was scheduled to receive three fractions of HDRB over 3 weeks. Those in groups A were assessed for the exact treatment fraction missed, the cause and duration of treatment interruption and the actions taken to compensate for non-execution of treatment. RESULTS: A total of 90 patients fall into group A and most (41) of them experienced interruptions in the third fraction of their treatment. The most frequent (44%) causes of treatment interruptions observed among them were patient-related. Record of compensation for treatment interruption was not found in patients' treatment folders. This action may be due to lack of functional procedures for managing treatment interruptions and insufficient follow-up of patients, who never came back for consideration for compensation. CONCLUSION: This study showed that radiation oncology centres need to review their policies for managing treatment interruptions and documentation. Also, the mechanism for patients' follow-up should be strengthened to a reasonable extent to achieve better radiotherapy care.

Pattern of paediatric malignancies seen at the Radiotherapy Department of the University College Hospital, Ibadan, Nigeria.

BACKGROUND: Paediatric tumours are seen by the radiotherapist following referral from other specialists. Patients seen by the radiotherapists may not conform to the full spectrum seen in the hospital. OBJECTIVE: To review the pattern of presentation of paediatric malignancies seen at the radiotherapy department of the UCH, Ibadan. METHODS: Retrospective study of all patients below the age of 12 seen in Radiotherapy Department of UCH, Ibadan over a 19-year period was undertaken. Data were collected from the case files and the radiotherapy treatment cards. RESULTS: 244 cases were evaluated with age ranged between 4 months and 12 years. Male to female ratio was 1.15 to 1.0. 23 tumour types were seen with retinoblastoma accounting for about 45% of all the patients reviewed. Burkitt's lymphoma accounted for only about 2.5%. CONCLUSION: Retinoblastoma, nephroblastoma, intracranial malignancies and rhabdomyosarcoma are the tumours most commonly seen at the Radiotherapy Department of the UCH, Ibadan.

Comparison of entrance surface doses of some X ray examinations with CEC reference doses.

Entrance surface dose (ESD) measurements have been carried out in Nigeria as part of the ongoing dose reduction programme. Thermoluminescence dosemeters (TLD) were used to measure skin entrance doses for four common radiographic views in three hospitals. The mean ESD for the PA chest examination in all the participating hospitals was in the range 0.12 - 4.46 mGy. The mean ESD for the AP skull. PA skull and LAT skull were 8.55, 5.17 and 6.97 mGy respectively. The mean ESD values are greater than the CEC reference doses, except for rooms 1 and 2 in UCH where the entrance surface doses for PA chest examination are below the CEC reference dose. The QA test results show non-compliance of the accuracy of tube voltage with acceptance limit in three rooms. The timer accuracy is also not within the acceptance limit in two rooms. The reproducibility of both the kVp and timer in all the rooms is good.

Advanced cervical carcinoma in Ibadan, Nigeria: an appraisal of radiation therapy.

This is a retrospective study of 500 patients with advanced cervical cancer (FIGO Stages IIB, III and IVA) who were seen and managed at the University College Hospital Ibadan between 1988 and 1992. External pelvic radiation therapy plus intractivary radioactive caesium brachytherapy was mainstay of treatment. Complete response to therapy was recorded in 68% of patients with stage IIB, 57% in stage III and 41.2% of patients in stage IVA. In patients with stage IIB, the local tumour control was 65%, in stage III patients 54% and in patients with stage IV 41%. The cumulative rates of survival at 5 years (for all the patients-with stage IIB, III and IVa) were 41.5%. The cumulative rates for disease-free survival at 5 years was 25.5%. Radiotherapy as the sole treatment modality in the management of advanced cervical cancer in Ibadan has yielded poor results as revealed in this study. There is an urgent need to evolve a new treatment policy with the aim of improving the response rate and survival in this group of patients.