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Purpose Source strength (Sk), sizes of vaginal cylinder applicators (VCA), number of dwell positions (DPs), and the prescribed dose (D) are basic parameters in brachytherapy (BT) treatment planning contributing to total dwell time (TDT). This study was aimed at assessing the relationships between the specified variables in an attempt to verify the TDT in high‐dose‐rate (HDR) vaginal cylinder applications. Methods One hundred and twenty‐one patients treated with Gynesource‐Co60 (Bebig, Germany) using VCAs of diameters 20, 25, and 30 mm at University College Hospital, Nigeria, were enrolled in this study. Brachytherapy doses ranging from 3 to 7 Gy were always prescribed to points 5 mm away from the cylinder's surface. Treatment planning was undertaken on HDR‐Basic treatment planning system (TPS) which utilizes source step size of 5 mm. Data on the stated parameters related to the first BT fractions of the patients were acquired. With the aid of EViews statistical software, two forms of mathematical models were thereafter developed. The resulting TDTs from the models were compared with the TPS values using Minitab statistical software. Results The relationships obtained for the increasing sizes of the VCA were TDT1(min)=2.22+3.17DSk;TDT1(min)=3.52+3.74DSk;TDT1(min)=−1.96+6.91DSkandTDT2(min)=0.50−0.03Sk+0.02D+0.55DPs;TDT2(min)=7.08−0.06Sk+0.02D+0.67DPs;TDT2(min)=7.02−0.11Sk+0.03D+1.25DPs The model‐based TDTs correlate with the TPS‐calculated values with r1 = 0.80 (P = 0.412) and r2 = 0.97 (P = 0.468). Conclusions The findings of this study could suggest likely variations in the treatment time when certain changes occur in the related parameters. The increasing size of the vaginal cylinder has a positive influence on the brachytherapy treatment time. The latter model has been a useful tool in the verification of the dose delivery time at the first HDR brachytherapy center in Nigeria and West Africa.

OBJECTIVE: This study assessed bladder and rectal dose based on Cartesian-coordinates in intracavitary brachytherapy and examined the variations resulting from use of tandem-ring (T-R) of different angles. METHODS: Cartesian-co-ordinates of bladder and rectum points were derived on orthogonal-radiographs of 90 patients who had high-dose-rate brachytherapy for cervical cancer at the Department of Radiation Oncology, University College Hospital, Ibadan, Nigeria. The patients were classified in three groups of 30, based on T-R angles 30°, 45° and 60° used, bearing same lengths and diameters across sets. The measured co-ordinates and the related percentage doses to points of interest in the two organs were analysed using EViews and SPSS statistical softwares. RESULTS: The mean rectal point dose (RPD) obtained was 68.97 ± 13.57 % of the prescribed doses as against 56.57 ± 11.83% for bladder point dose. While the maximums of the mean RPD were 95.7, 90.5 and 82.5% for T-R angles 30°, 45° and 60° respectively; corresponding values for the bladder point were 72.8, 87.8 and 62.3%. CONCLUSION: The baseline data obtained in this study served as guidelines for subsequently achieving acceptable values of bladder point dose and RPD at University College Hospital, Nigeria. Special attention should be paid to the application of 2 cm-tandems in relation to the RPD. ADVANCES IN KNOWLEDGE: This is one of the few studies assessing the influence of T-R angles on organs-at-risk. The increase in RPD with the use of intrauterine tandem-2 cm is found to be most pronounced with T-R 30(0), and this trend reduced with larger angles.

Background: The role of Computed Tomography (CT) in the medical diagnosis of diseases has greatly expanded, despite the potential risk of cancer following exposures to ionising radiation (XRay) from this modality. This risk is particularly of great concern in children, who are more radiosensitive and have many years to manifest radiation effect than adults. Aims: To estimate risk of cancer induction from Pediatric cranial CT. Materials and Methods: A total of 203 patients, who were referred from various pediatric clinics and wards for cranial CT in a teaching hospital in the South Western Nigeria between the year 2011 and 2013 were considered. All patients were grouped into four age (year) groups: less than 1, 1-5, 5-10 and 10-15. A mathematical method was used to estimate the risk of cancer from the Original Research Article Atalabi et al.; BJMMR, 9(10): 1-7, 2015; Article no.BJMMR.18079 2 effective dose(ED) calculated from volume computed tomography dose index (CTDIvol), dose length product (DLP) and standard conversion factor. Results: The range of CTDIvol (mGy) received by all patients was 10–250 mGy while majority of the patients received 50–100. The range of DLP (mGy.cm) received by all patients and majority of patients was 500–5000 and 2001–2500 respectively. The range of ED (mSv) received by all patients and majority of the patients was 1–25 and 5–10 respectively. The risk estimated with respect to patients’ age showed that patient in the age group 1–5 years have the highest risk of cancer induction while the risk based on gender showed no significant difference. Conclusion: Over 60% of pediatric patients received more than the recommended values of CTDIvol, DLP and ED from cranial CT. Urgent steps must be taken to ensure compliant with international recommended precautions for dose reduction in pediatric medical imaging.

PURPOSE In-vivo measurements to determine doses to organs-at-risk can be an essential part of brachytherapy quality assurance (QA). This study compares calculated doses to the rectum with measured dose values as a means of QA in vaginal vault brachytherapy using cylinder applicators. MATERIAL AND METHODS At the Department of Radiotherapy, University College Hospital (UCH), Ibadan, Nigeria, intracavitary brachytherapy (ICBT) was delivered by a GyneSource high-dose-rate (HDR) unit with (60)Co. Standard 2D treatment plans were created with HDR basic 2.6 software for prescription doses 5-7 Gy at points 5 mm away from the posterior surface of vaginal cylinder applicators (20, 25, and 30 mm diameters). The LiF:Mg, Ti thermoluminescent dosimeter rods (1 x 6 mm) were irradiated to a dose of 7 Gy on Theratron (60)Co machine for calibration purpose prior to clinical use. Measurements in each of 34 insertions involving fourteen patients were performed with 5 TLD-100 rods placed along a re-usable rectal marker positioned in the rectum. The dosimeters were read in Harshaw 3500 TLD reader and compared with doses derived from the treatment planning system (TPS) at 1 cm away from the dose prescription points. RESULTS The mean calculated and measured doses ranged from 2.1-3.8 Gy and 1.2-5.6 Gy with averages of 3.0 ± 0.5 Gy and 3.1 ± 1.1 Gy, respectively, for treatment lengths 2-8 cm along the cylinder-applicators. The mean values correspond to 48.9% and 50.8% of the prescribed doses, respectively. The deviations of the mean in-vivo doses from the TPS values ranged from -1.9 to 2.1 Gy with a p-value of 0.427. CONCLUSIONS This study was part of efforts to verify rectal dose obtained from the TPS during vaginal vault brachytherapy. There was no significant difference in the dose to the rectum from the two methods of measurements.

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.

Background : Pain is a symptom of both physical and psychological disorder in patients. Pain may be acute or chronic. Chronic pain can also be the consequence of progressive diseases such as cancer. Cancer pain can be defined as a complex sensation that reflects both damage to the body and the body's response to the damage. Proper pain management is crucial in the overall care of patients. The doctor-patient ratio is still low in Nigeria according to World Health Organization (WHO) 2012, we have 1:3500 doctor-patient ratio as against the standard 1:600, but that of nurse-patient is better, 1:30 as against WHO standard of 1:6, however more nurses are needed to meet the need of the rising population of Nigeria. Incidence of cancer is rising worldwide and majority of the advanced cases occur in the developing countries like Nigeria. In order to uphold the standard of cancer pain management in our patients, active participation of the nurses is essential. More importantly all health professionals need to serve as advocates for adequate cancer pain control and should ensure that pain treatment is based on ethical principles and evidence-based standards. However nurses play a critical role in effective pain management because they have more contact time with patients in any healthcare setting. This vantage position gives the nurse a unique privilege to identify patients who have pain, assess the pain and its impact on the patients and their family members, thus initiate actions to manage the pain and evaluate the effectiveness of those actions. Aims and Objectives: This study is aimed at assessing the level of knowledge of cancer pain management among trained Nurses at the University College Hospital (UCH), Ibadan, Nigeria. Materials and Methods: Trained nurses who consented to take part in the study were tested using self-administered questionnaire. The questionnaires consisted of 3 major sections namely (a) Demography, (b) Pain assessment, (c) Cancer Pain management. Their individual level of knowledge of cancer pain management was thereafter assessed from their response to the questionnaires. Results: 119 N urses completed the questionnaire. 105 (88.24%) were double qualified, Registered Nurse (RN) and Registered Midwife (RM), while 10 (8.40%) had only RN certificate. Approximately 21 (18%) respondents had additional formal training in pain management. 100 (84%) respondents gave correct definition of pain and out of these, only 2 (2%) could give a good account on the management for cancer pain. 24 (20%) of the respondent could use Visual Analogue Scale (VAS) for pain assessment. Only 23 (19%) could state the relevance of opioids in cancer pain management. Conclusion: This study revealed inadequate knowledge in cancer pain management among the nurses. To achieve holistic care for cancer patients in all health care delivery centers, additional training in pain management is required.

Patient dosimetry studies in diagnostic radiology in Nigeria have been on measurement of entrance skin dose and effective dose. Another important and easy to measure radiation dose descriptor that could be used to assess patient dose in radiological procedures is dose area product (DAP). Knowledge of DAP with location and projection of X‐ray beam allows direct calculation of organ dose and effective dose. In this study, DAP for commonly performed radiological examinations (abdomen, chest, lumbo sacral joint, pelvis, paranasal sinus, and skull) in four diagnostic centers in Nigeria were determined. These centers comprise of three classes of health care center namely tertiary, private, and specialist hospitals. Mathematical method was used to determine DAP received by 336 patients undergoing radiological examinations at the selected diagnostic centers. The DAP received by patient from each radiological examination varies from center to center. The range factor (RF) of DAP for individual patients ranged from 1.55–4.56, while RF of DAP among the selected centers was 2.27–55.84. The highest RF of DAP (55.84) was obtained from X‐ray examination of the chest. This variation was due to the application of anti‐scatter grid, and high kVp and high mAs values for chest examination by only one of the centers. The very wide variation in DAP found among diagnostic centers in this survey showed that there is need to harmonize radiological techniques of common X‐ray examination among different diagnostic centers. This would ensure optimal protection of patient against excessive radiation dose. PACS numbers: 87.53.Bn; 87.59.B

The main objective of this work was to show that a gamma camera in a developing country could perform efficiently despite electricity outages using intrinsic flood uniformity tests as an index of performance. A total of 143 intrinsic uniformity test results for a new gamma camera in use in an environment with unstable power supply are presented. The integral uniformity for the central field of view (CFOV) was found to be between 3.43% and 1.49% (3.29% for acceptance test) while the integral uniformity for the useful field of view (UFOV) was between 4.51% and 1.9% (5.21% for acceptance test). The differential uniformity for the CFOV was between 1.99% and 1.04% (2.25% for acceptance test) while that of the UFOV was between 2.84% and 1.23% (2.63% for acceptance test). In conclusion, these results show that the uniformity of the gamma camera under this condition is within an acceptable range for both planar and SPET imaging.

Iridium-192 is widely used for high-dose rate brachytherapy. Co-60 source with similar geometric and dosimetric properties are now available. It has a longer half life but higher energy than Iridium-192. If Co-60 source can produce similar results, it will be more economical for low resource settings. Objective To evaluate the acute gastrointestinal and genitourinary toxicity associated with Co-60 source in the brachytherapy of cervical cancer. Methods Seventy patients with cervical cancer received 45 Gy in 22 fractions of pelvic external beam radiotherapy and 19.5 Gy in 3 fractions of HDR with Co-60 source using tandem and ring applicators with 6 courses of cisplatin 50 mg/m2 and 5 fluorouracil 1000 mg/m2 every 3 weeks Toxicity was scored using NCI-CTC version 4.0. Results The median total BED (Gy10) for tumor was 86.2 (84.4–88.8) while that for rectum (BED Gy3) was 124.4 (120–133). Two patients (3%) had grade 3 gastrointestinal toxicity while all others had ≤grade 2 toxicity and this is comparable with previous results. Conclusion Co-60 as HDR brachytherapy source is tolerable and is economical for low resource settings.

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. NQJHM Vol. 17 (4) 2007: pp. 152-154

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.

Background: The Iridium-192 radionuclide source is commonly used for high-dose-rate brachytherapy of uterine cervical cancer. The cobalt-60 radionuclide source, which is more economical, is now available with dosimetric properties similar to iridium-192. Objective: To evaluate late gastrointestinal and genitourinary complications, and also the survival pattern in cervical cancer patients treated with cobalt-60 high-dose-rate brachytherapy, three years after treatment. Materials and Methods: Seventy patients, who were treated with high-dose-rate brachytherapy using the cobalt-60 radionuclide source were followed up for three years. All the patients received 45 Gy of external beam radiotherapy in 22 daily fractions, with 19.5 Gy from high-dose-rate brachytherapy, in three fractions, over three weeks, using the cobalt-60 radio nuclide source. The patients also received concurrent cisplatin-based chemotherapy. Late complications were assessed every three months, using Radiation Therapy Oncology Group (RTOG) late toxicity criteria. The pattern of disease control was also assessed. Results: Late complications in the bowel were, six (9%) grade 1, four (6%) grade 2, one (1%) grade 3, and one (1%) grade 4. The late complications affecting the bladder were 5 (7%) grade 1 and 1 (1%) grade 4. Twenty-eight patients (40%) were alive without disease, seven (10%) were alive with disease, seven (10%) died of persistent disease, four (6%) died of metastatic disease, while 24 (34%) were lost to follow-up. Conclusion: The late complications were similar to those reported for Iridium-192 as a source of high-dose brachytherapy. Cobalt-60 high-dose-rate brachytherapy is tolerable, effective, and economical for low resource settings.