A systematic review of occupational radiation individual dose monitoring among healthcare workers exposed in Africa.

Dosimetric monitoring is useful to limit exposures to ionising radiation in medical occupational settings, and reduce subsequent health risks. Scientific literatures, such as the UNSCEAR report 2017 and International Atomic Energy Agency Report 2014b, updated information on this subject; however, few African works have been found. This is the reason why we undertook this study, which summarises existing information on monitoring external radiation exposure doses for the whole body, using data from medical workers on this continent. Using standard terms and combining different keyword searches for radiation dose monitoring among radiology healthcare workers in Africa, from the titles, abstracts, and full texts, we found 3139 articles in the PubMed/MEDLINE, Google Scholar and INIS databases. Two reviewers screened the retrieved publications based on predefined eligibility criteria to identify relevant studies, extract key information from each, and summarise the data in table form. A total of 20 potentially relevant articles were identified. Among these 20 articles, 15 reported the overall average annual effective dose. Studies included in this systematic review represent an inventory of the radiation protection of medical workers in various African countries, with a focus on the monitoring of occupational radiation exposure. The size of studied populations ranged between 81 and 5152 occupational exposed workers. The mean annual effective doses ranged from 0.44 to 8.20 mSv in all specialities of medical sectors, while diagnostic radiology ranged from 0.07 to 4.37 mSv. For the nuclear medicine and radiotherapy from medical groups, the mean annual effective dose varied between 0.56 and 6.30 mSv. Industrial and research/teaching sectors data varied between 0.38 to 19.40 mSv. In conclusion, more studies implemented on dosimetric monitoring in Africa are needed to get a real picture of occupational exposure in the continent.

Radiomics-Based Classification of Tumor and Healthy Liver on Computed Tomography Images.

Liver malignancies, particularly hepatocellular carcinoma and metastasis, stand as prominent contributors to cancer mortality. Much of the data from abdominal computed tomography images remain underused by radiologists. This study explores the application of machine learning in differentiating tumor tissue from healthy liver tissue using radiomics features. Preoperative contrast-enhanced images of 94 patients were used. A total of 1686 features classified as first-order, second-order, higher-order, and shape statistics were extracted from the regions of interest of each patient's imaging data. Then, the variance threshold, the selection of statistically significant variables using the Student's t-test, and lasso regression were used for feature selection. Six classifiers were used to identify tumor and non-tumor liver tissue, including random forest, support vector machines, naive Bayes, adaptive boosting, extreme gradient boosting, and logistic regression. Grid search was used as a hyperparameter tuning technique, and a 10-fold cross-validation procedure was applied. The area under the receiver operating curve (AUROC) assessed the performance. The AUROC scores varied from 0.5929 to 0.9268, with naive Bayes achieving the best score. The radiomics features extracted were classified with a good score, and the radiomics signature enabled a prognostic biomarker for hepatic tumor screening.

[Multifocal tuberculosis simulating multimetastatic colon cancer in an immunocompetent black African patient: a case report]. / Tuberculose multifocale simulant un cancer du côlon multi-métastatique chez un Noir africain immunocompétent: à propos d´un cas.

Multifocal tuberculosis is rare in immunocompetent subjects. It is characterized by the involvement of at least two extra-pulmonary sites, associated or not with lung disease. It is often difficult to diagnose. We here report a case of multifocal tuberculosis in a non-immunocompromised black African subject at the Hubert Koutoukou Maga National Hospital and University Center (CNHU-HKM) in Cotonou, Benin. The study involved a 23-year-old man, with no particular previous history, admitted with diffuse abdominal pain associated with alteration of general state. Clinical examination showed severe malnutrition and medium-volume ascites. Imaging tests (chest X-ray, ultrasound and computed tomography (CT) scan) showed multiple lung, liver, pancreatic, bone, lymph nodes and colic lesions suggesting multimetastatic tumor. Colonoscopy then showed budding lesion of the cecum. GeneXpert test showed Koch´s bacilli. The anatomo-pathological examination of colic biopsies and GeneXpert sputum test confirmed multifocal tuberculosis. The patient received antituberculosis treatment and nutritional support. However he died. Multifocal tuberculosis is a serious disease that is difficult to diagnose. Then it is frequently mis-diagnosed in tropical areas, especially when it occurs in immunocompetent patients.

Experimental Assessment of Workplace Radiation Exposure in Diagnostic X-ray Medical Imaging Centres in Benin from 2019 to 2020.

The ease of prescribing radiological examinations has prompted an expansion in radiological procedures and, consequently, an increase of occupational dose to medical imaging workers. However, little is known about radiation exposure in the workplace of medical radiology professionals in many countries, and in Benin particularly. The purpose of this study was to assess ambient radiation doses in diagnostic X-ray medical facilities in Benin and to observe whether exposure levels are below reference levels. A total of 72 public and private medical imaging centres participated in a cross-sectional study carried out from June 2019 to February 2020 in Benin. These centres had 59 X-ray, four chest and six computed tomography (CT) scan rooms. A calibrated radiameter able to measure short, pulsed or continuous X fields and gamma/beta (50 nSv to 10 Sv) was used to measure exposure levels in these functional rooms. Scattered X-ray doses and exposure time from radiological examinations both behind the lead glass of the control area to assess the levels of exposure of professionals and outside of the examination room to evaluate the level of exposure of the public (including non-exposed workers) have been provided. Equivalent doses estimated per hour were compared with the reference levels of 7.50 and 0.05 µSv per hour for workers and the public, respectively. At the control area, the mean/median (min-max) equivalent doses were 0.09/0.07 (0.00-0.21), 2.39/0.13 (0.00-75.67), and 228.39/28.65 (0.39-869.75) µSv per hour for the chest, X-ray, and CT-scan rooms, respectively. Among 69 examination rooms, 13.04% of the equivalent dose estimated in the workplace behind the lead glass was greater than 7.50 µSv per hour; 65 out of 69 examination rooms showed that 40.00% of the equivalent dose estimated behind the doors was greater than 0.05 µSv per hour. These results demonstrated that current controls, including leaded glass separating the control panel and leaded doors between the examination room and the corridor, are inadequate to limit radiation exposures. The controls must be upgraded and a dosimetry program should be implemented to monitor exposures of employees, patients, and visitors.

Melorheostosis with bilateral involvement in a black African patient.

Melorheostosis is a rare chronic bone disease of unknown etiology that often affects a single limb. Onset usually occurs in childhood or early adolescence. A flowing wax appearance along the surface of the bone and multiple areas of bone sclerosis produce a typical radiographic picture. We describe the first case reported in a black African, in whom an exceedingly rare feature was a bilateral distribution of the lesions.

[Vesicouterine fistula: report on 15 cases at Cotonou University Urology Clinic]. / La fistule vésico-utérine: à propos de 15 cas à la Clinique Universitaire d'Urologie de Cotonou.

OBJECTIVE: To analyse the clinical and radiological features of cases of vesicouterine fistula (VUF) seen in the department and the results of treatment in order to improve the therapeutic management of patients with VUF. MATERIAL AND METHODS: The medical records of 17 woman admitted to the department and treated for vesicouterine fistula between 01/01/1994 and 15/06/2001 were reviewed. Two were excluded from this essentially retrospective study, as they were considered to be uninterpretable due to missing data. Predefined forms comprising the parameters indicated in the text constituted the basis of this study. RESULTS: The authors indicate that VUF is a rare disease: 17 cases in 7 and a half years. Detailed review of 15 cases showed that the constant presenting complaint is permanent urine leak from the cervix. It was isolated in 12 cases and associated with "vesical menstrual periods" in 3 cases. Women between the ages of 30 and 39 years were the most frequently affected. Pauciparous women were more frequently affected (7 out of 15 cases). Caesarean section was incriminated in 14 out of 15 cases. 11 out of 15 subjects consulted after at least one year of symptoms. The margins of the fistula were fibrotic in 11 cases, which did not prevent satisfactory results, with 14 cures out of 15 cases after the first surgical operation. CONCLUSION: VUF is an uncommon and very frequently iatrogenic disease, in which the presenting complaint is permanent urine leak from the genital tract, either isolated or associated with cyclic haematuria. Even when patients are seen late, with fibrotic margins, surgical treatment of VUF achieves a good cure rate. The best treatment is prevention, based on a perfect caesarean section technique.

Ultrasound diagnosis of varicocele in the adolescent: our experience from Benin.

BACKGROUND: The diagnosis of varicocèle is clinical. In order to improve diagnosis of varicocele, we compared the clinical with the ultrasound findings in schoolboys with the condition. This is because the conditions can affect testicular growth. PATIENTS AND METHODS: It was a cross-sectional, descriptive study of schoolboys aged from 10 to 19 years who had varicocele. Among 2724 boys examined, 149 had varicocele and only 81 had scrotal (18 with Doppler) and renal ultrasound examination. RESULTS: Among the 81 adolescents who were clinically diagnosed with varicocele and also with the aid of ultrasound scan, 25, 36 and 20 had grade 1, 2 and 3, respectively. Testicular hypotrophy (TH) was clinically noticed in 17 cases. At ultrasonography, varicocele was bilateral in 87.66% and unilateral in 12.34% (P = 0.01) with 32 adolescents (39.51%) showing TH compared with 20.99% being diagnosed with TH using clinical examination alone (P = 0.01). In 50 schoolboys (61.73%) with unilateral varicocele, a subclinical type was discovered at other side. Renal ultrasound revealed abnormalities in 4.93% of cases. Doppler ultrasound helped in finding varicoceles along the top edge of the testis (n = 15) and under tunica albuginea (n = 3). CONCLUSION: TH due to varicocele is better studied by ultrasound.

Profil à l'imagerie par résonnance magnétique (IRM) des lésions traumatiques du genou avec radiographie normale

Objectifs : A travers cette étude, nous envisageons effectuer un panorama des lésions découvertes à l'IRM chez les traumatisés du genou à radiographie standard normale. Matériels et méthode : Etude descriptive transversale réalisée sur une période de 28 mois portant sur 211 patients traumatisés du genou ayant une radiographie standard normale, adressés pour une IRM du genou. Résultats : Sur les 211 dossiers, nous avons colligés 80 cas de lésions soit 38,1% avec une prédominance masculine (sex ratio 1,6). Les atteintes rencontrées par ordre de fréquence étaient : méniscales (55,9%), ligaments croisés (37%), ligaments collatéraux (18%), rétinacula (13%), appareil extenseur (8,6%), contusion osseuse (20%) ; épanchement articulaire (66,7). Ces lésions étaient dominées par des lésions du compartiment médial du genou avec en chef de file l'atteinte du ménisque médial suivi des atteintes du LCA. Les atteintes du ménisque médial sont souvent aussi associées à celles du ligament collatéral médial (LCM). Conclusion : Au terme de ce travail, nous pouvons affirmer que l'IRM a permis de déterminer un nombre non négligeable de lésions ménisco-ligamentaires et osseuses non visibles en radiographie standard montrant les limites de cette dernière