External Beam Radiotherapy in Western Africa: 1969-2019.

AIMS: We describe the absolute and per capita numbers of megavoltage radiotherapy machines (MVMs) in Western Africa from 1969 to 2019. MATERIALS AND METHODS: Western Africa was defined in accordance with the United Nations' delineation and inclusive of 16 countries. A literature search for publications detailing the number of cobalt-60 machines (COs) and linear accelerators (LINACs) in radiotherapy centres was carried out. Population data from the World Bank Group and crude cancer rates from the International Agency for Research on Cancer were used to calculate ratios of million persons per MVM and MVMs per 1000 cancer cases. RESULTS: The numbers of MVMs in Western Africa in 1969, 1979, 1989, 1999 and 2009 were zero, two, three, six and nine, respectively. In 2019 there were 22 MVMs distributed across Ghana (five), Côte d'Ivoire (two), Mali (one), Mauritania (two), Nigeria (nine) and Senegal (three). Nine countries (56.3%) had no history of external beam radiotherapy (EBRT). The largest increase in absolute EBRT capacity occurred from 2017 to 2019, during which 13 MVMs were commissioned. The largest decrease in EBRT capacity occurred from 2015 to 2017, during which four LINACs and three COs were rendered non-operational. The ratio of million persons per MVM improved from 67.0 in 1979 to 17.8 in 2019. As of 2019, there was 0.09 MVM per 1000 cancer cases. CONCLUSIONS: Western African nations have experienced an increase in the absolute number of MVMs and per capita radiotherapy capacity during the last 50 years, especially in the last decade. As non-functional LINACs contributed to a temporary decline in the EBRT infrastructure, dual use of CO/LINAC technologies may act to promote the availability of EBRT treatment in centres with capacity for multiple MVMs.

Determination of neutron energy spectrum at KAMINI shielding experiment location.

The neutron spectrum at KAMINI reactor south beam tube end has been determined using multifoil activation method. This beam tube is being used for characterizing neutron attenuation of novel shield materials. Starting from a computed guess spectrum, the spectrum adjustment/unfolding procedure makes use of minimization of a modified constraint function representing (a) least squared deviations between the measured and calculated reaction rates, (b) a measure of sharp fluctuations in the adjusted spectrum and (c) the square of the deviation of adjusted spectrum from the guess spectrum. The adjusted/unfolded spectrum predicts the reaction rates accurately. The results of this new procedure are compared with those of widely used SAND-II code.

Implementation status of self-assessment/peer-group discussion program: a bottom-up approach of monitoring/supervision in improving quality of health services.

BACKGROUND: Monitoring/supervision is an essential component for improving the quality of health services including rational use of medicines. A new bottom-up approach of monitoring/supervision consisting of self-assessment/ peer-group discussion was found to be effective in improving prescribing practices. The new strategy significantly improved the prescribing practices based on standard treatment guidelines. The government has implemented it as a Program in primary health care services of Nepal. This article aims to share the implementation status of the self-assessment/peer-group discussion Program for improving the prescribing practices of common health problems and availability of drugs in the district health system. METHODS: Concurrent mixed research design was applied for data collection. The data were collected at different levels of health care system using in-depth interviews, participatory observations and documentary analysis. RESULTS: The Management Division, Department of Health Services implemented the Program in 2009-10 and the PHC Revitalization Division, DoHs is the implementation division since 2010-11. The Program comprised revision of participant's and trainer's manuals, training of trainers and prescribers, finalisation of health conditions and indicators, distribution of carbon copy prescription pads, and conduction of peer-group discussions.The Program was implemented in number of districts. CONCLUSIONS: The government made the policy decision to implement the Program for monitoring prescribing practices and the availability of free drugs in districts. However, it has covered only few districts and needs escalation to cover all 75 districts of the country.

Improving private drug sellers' practices for managing common health problems in Nepal.

BACKGROUND: In most Asian countries, 50 - 90% of pharmaceutical sales are made in private drug outlets, by personnel with some training in drugs but not for the treatment of common health problems. The objective of the study was to determine effects of focused training for private drug sellers to improve practices in treating acute respiratory infections and diarrhoea in children, and anaemia in pregnancy in Nepal. METHODS: Randomized controlled, four way nested design study incorporating four interventions for drug retailers in both hill and terai districts. One group received mailed printed educational materials followed by mailed feedback; a second received small group training followed by feedback; a third received small group training only; and a fourth, the control group, received no intervention. Surrogate customer method was used to assess practices. Outcomes were measured using multivariate linear regression. RESULTS: A significant increase in the asking of key history questions, recommendation ( prescribing by drug retailers) of cotrimoxazole, and advice-giving for pneumonia; a significant increase in ORS recommendation, and advice giving for diarrhoea including the avoidance of antidiarrhoeals; and a significant increase in asking key history questions and recommending appropriate products in pregnancy cases. CONCLUSIONS: Training intervention as well as training followed by practice feedback was effective in improving the management of common illnesses and pregnancy by private drug sellers.

Charged-particle spectroscopy for diagnosing shock ρR and strength in NIF implosions.

The compact Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the National Ignition Facility (NIF) as a National Ignition Campaign diagnostic. The WRF measures the spectrum of protons from D-(3)He reactions in tuning-campaign implosions containing D and (3)He gas; in this work we report on the first proton spectroscopy measurement on the NIF using WRFs. The energy downshift of the 14.7-MeV proton is directly related to the total ρR through the plasma stopping power. Additionally, the shock proton yield is measured, which is a metric of the final merged shock strength.

Imaging of high-energy x-ray emission from cryogenic thermonuclear fuel implosions on the NIF.

Accurately assessing and optimizing the implosion performance of inertial confinement fusion capsules is a crucial step to achieving ignition on the NIF. We have applied differential filtering (matched Ross filter pairs) to provide broadband time-integrated absolute x-ray self-emission images of the imploded core of cryogenic layered implosions. This diagnostic measures the temperature- and density-sensitive bremsstrahlung emission and provides estimates of hot spot mass, mix mass, and pressure.

Hard x-ray (>100 keV) imager to measure hot electron preheat for indirectly driven capsule implosions on the NIF.

We have fielded a hard x-ray (>100 keV) imager with high aspect ratio pinholes to measure the spatially resolved bremsstrahlung emission from energetic electrons slowing in a plastic ablator shell during indirectly driven implosions at the National Ignition Facility. These electrons are generated in laser plasma interactions and are a source of preheat to the deuterium-tritium fuel. First measurements show that hot electron preheat does not limit obtaining the fuel areal densities required for ignition and burn.

Characterizing high energy spectra of NIF ignition Hohlraums using a differentially filtered high energy multipinhole x-ray imager.

Understanding hot electron distributions generated inside Hohlraums is important to the national ignition campaign for controlling implosion symmetry and sources of preheat. While direct imaging of hot electrons is difficult, their spatial distribution and spectrum can be deduced by detecting high energy x-rays generated as they interact with target materials. We used an array of 18 pinholes with four independent filter combinations to image entire Hohlraums with a magnification of 0.87× during the Hohlraum energetics campaign on NIF. Comparing our results with Hohlraum simulations indicates that the characteristic 10-40 keV hot electrons are mainly generated from backscattered laser-plasma interactions rather than from Hohlraum hydrodynamics.

Community intervention to improve knowledge and practices on commonly used drugs.

BACKGROUND: World Health Organisation (WHO) estimates that about half of all medicines are inappropriately prescribed, dispensed and sold and about half of all patients fail to take their medicines properly. OBJECTIVE: The overall objective of the study was improving use of medicines in the community by creating awareness among different target groups. MATERIALS AND METHODS: It was a pre-post comparison of intervention implemented at the community level in purposively selected Bhaktapur District of Kathmandu Valley, Nepal. The study was conducted in the private schools of the study district. Twelve schools were randomly selected. Thereafter, students from 6-9 grades were listed from the selected schools. Then 15% of the total students in each grade were randomly selected to get six students from each grade of the each school, totaling 288 students. The households of the selected students served as the sample households for the study. Thus, there were 288 households sampled for the study. The intervention and the targeted intermediary groups consisted of a. training of schools teachers b. training of journalists c. interactive discussions of trained school teachers with school children using key messages and c. communication of key messages through the local F.M. radio, newspaper/magazine. RESULTS: There was a significant increase in correct knowledge on action of antibiotics and excellent knowledge on the methods of administration of antibiotics of households after the intervention. Similarly, there was a significant increase in knowledge on cough as a disease and a significant decrease in the use of cough medicines after intervention. There was also a significant increase in excellent knowledge on the sources of vitamins and a significant decrease in the use of vitamin/tonics after the intervention. CONCLUSION: The participation of intermediary groups eg. school teachers, journalists and school children in the implementation of intervention were successful. The groups have fulfilled the commitments in implementing the plan of action. The key messages have effectively reached the households, and the knowledge and practices of the community members in drug use have improved.

An intervention improving prescribing practices and monitoring drugs availability in a district.

To improve the quality of health care in Nepal, supervision/ monitoring involving periodic visits by the district supervisor to health facilities (top-down approach) is in practice. It is not objectively implemented because of time and financial constraints and terrain of the country. To assess the effectiveness of a pre-tested strategy i.e. peer-group discussion with self-assessment piloted through the district health system in improving quality of care. A pre-post pilot study was conducted in 41 PHC facilities of Chitwan district of Central Nepal. The intervention included small-group training to prescribers followed by peer-group discussion with self-assessment data. It involved visit of in-charges from health facilities to district level regular meeting with self-assessment data on the treatment of four targeted health problems and also the availability of drugs of their health facilities as well as from health facilities which were under their supervision (bottom-up approach). In under-five children, there was a significant improvement in use of antimicrobials in diarrhoea, paracetamol alone and antibiotics in no pneumonia, and co-trimoxazole or amoxycillin alone or with paracetamol in pneumonia. The use of benzyl benzoate or gamma benzene hexachloride alone and antibiotics in scabies were also significantly improved. The peer-group discussion, a bottom-up approach of supervision/monitoring implemented through district health system improves the prescribing practices and availability of drugs in the district.

Evaluation of a successful intervention for sustainability and effects in post research phase.

INTRODUCTION: Promoting appropriate use of drugs is an essential element in achieving quality of health and medical cares for patients and the community, and also to minimize financial burden. OBJECTIVE: The objective of this paper is to assess the successful intervention for sustainability and effects in post research phase. To address these problems, a variety of educational, managerial and regulatory strategies to improve prescribing have been tried in Nepal. When training is combined with a managerial intervention i.e. peer-group discussion, it results into improved changes in prescribing practices of paramedics in several practices. METHODOLOGY: A prospective, three-way design study consisting of small group training, small group training followed by peer-group discussion and control was conducted in three regions of Nepal including one hill and two terai (plains) districts from each region. The study included all health post from the sampled districts, making 80 health posts the study population. RESULTS: The study revealed the effectiveness of the peer-group discussion approach in improving the prescribing practices. An assessment to identify the sustainability of the strategy and its effect within the district healthcare system after the completion of the research phase was undertaken. The study found that peer-group discussion was discontinued in all targeted districts and the improved practices were not sustained after the completion of the research. Various reasons have been found for not continuing the effective intervention.

Intracranial adenoid cystic carcinoma--a case report.

Adenoid cystic carcinoma (ACC) is a relatively common malignant neoplasm which occurs in the head and neck region, particularly in the salivary glands. It is a slow growing, locally aggressive neoplasm with a unique feature of perineural spread. Intracranial extension can occur by direct extension, hematogenous metastases or by perineural spread. However, the occurrence of primary intracranial ACC with no evidence of a primary, is rare, with only ten cases reported in reviewed English literature until now. One such case is presented here with brief review of literature. This patient showed a good response to treatment with surgery followed by post-operative radiotherapy and has remained disease free, 32 months after the completion of treatment.

Leptomeningeal carcinomatosis from carcinoma of the palatine tonsil.

Distant metastases from carcinoma of the palatine tonsil are very uncommon. We encountered a case of a carcinoma involving the tonsillar region that resulted in subarachnoid mestastases following local radical radiotherapy. Metastases were diagnosed following magnetic resonance imaging and spinal fluid cytology. The patient succumbed to the disease after a rapid downhill course, 1 month following diagnosis of the secondary deposit. The present paper describes the rare site of distant metastasis and reviews the relevant literature.

Malignant melanoma presenting as bilateral breast masses.

Malignant melanoma presenting initially with disseminated disease is common. However, bilateral breast masses as the initial symptom of malignant melanoma are rare. One such case is detailed here, together with a review of literature.

Fine-needle aspiration cytology in the diagnosis of superficial lymphadenopathy: an analysis of 2,418 cases.

During a period of 5 yr, 2,418 fine-needle aspirations (FNA) were performed on 2,216 patients with superficial lymphadenopathy. Chronic nonspecific lymphadenitis was the commonest inflammatory lesion followed by tuberculosis. Among malignant lesions, metastatic tumors were most common followed by non-Hodgkin's lymphoma. The FNAC findings were correlated with subsequent histopathological diagnosis in 1,041 cases. The sensitivity rates of FNAC in tuberculosis, metastatic tumors, Hodgkin's disease, and non-Hodgkin's lymphoma were found to be 83.3, 97, 30, and 80.3%, respectively, the specificity being 94.3, 98.9, 98.6, and 95.4% in the same order. Immunocytochemical tests performed on the aspirated material helped in classifying the metastatic poorly differentiated tumors and confirming the diagnosis of non-Hodgkin's lymphomas. Effects of FNA on subsequent biopsy in 81 lymph nodes with benign hyperplasia were studied and showed that aspiration does not interfere with subsequent histologic assessment. Thus FNAC is a simple, inexpensive procedure, and when complemented by appropriate immunocytochemical studies is accurate and reliable for routine diagnosis of lymphadenopathy.

Application of fractal geometry techniques to the study of trabecular bone.

It is well recognized that both trabecular bone density and structure affect the overall bone quality and strength. In this study the aim is to quantify variations in the structural network of trabeculae using the concepts of fractal geometry. Fractal objects are objects that appear statistically similar over a range of scales. Typically fractals do not have smooth surfaces, but instead have rather complex structures with highly convoluted surfaces. Associated with every fractal is a characteristic dimension, called the fractal dimension. In this study, techniques of fractal analysis were used to characterize the trabecular bone matrix on digital images acquired by quantitative computed tomography (QCT) of dried excised human vertebral bodies (density ranging from 76-220 mg/cc) and photomicrography of transiliac crest biopsies. An automatic boundary tracking algorithm was used to identify the trabecular-bone and bone marrow interface, and a box-counting algorithm was used to estimate the fractal dimension of the trabecular boundary. Using this technique for fractal objects, if the boundary being analyzed is covered with boxes of differing sizes, epsilon, then the number of boxes N required to cover the surface increases indefinitely according to the relation N = epsilon-D, where D is the fractal dimension. Using this relationship in a preliminary study on five specimens we have found that the trabecular-bone boundary is fractal in nature. Using photomicrographs of iliac crest biopsies, it is found that the fractal dimension changes with the fractional trabecular bone content.(ABSTRACT TRUNCATED AT 250 WORDS)