Thyroid dose and cancer risk from head and neck computed tomography at two selected centres in Nigeria.

OBJECTIVE: The objective of this study was to evaluate the thyroid glands' radiation dose and the risk of thyroid cancer induction from head or neck computed tomography (CT) examinations. METHODS: In a prospective study, we evaluated all participants of all ages and sex referred for Head or Neck CT Scan at the University College Hospital, Ibadan and Me Cure Healthcare Limited, Ibadan, Oyo State, Nigeria. Thyroid radiation dose was estimated with impact scan calculator, and real-time dose measurement with thermoluminescent badge dosimeters (TLDs). Data were analysed and P < 0.05 was considered statistically significant. RESULTS: One hundred and sixty-three participants (128 adults and 35 children) participated in the study. In most participants (74%), the tube voltage was 120 kVp. The estimated median thyroid gland dose by the imPACT scan calculator was 4.95 mGy (range = 1.20-30.0 mGy) and 4.40 mGy (range = 3.0-5.10 mGy), while the real-time dose measured by the TLD was 4.79 mGy (range = 1.73-96.7 mGy) and 2.33 mGy (range = 1.20-3.73 mGy) at Centre A and B, respectively. The estimated median thyroid cancer risk was 2.88 × 10-6 (maximum range of 52 × 10-6) at centre A and a median value of 3.20 × 10-6 with a cancer risk estimate that may reach 17.9 × 10-6 recorded at centre B, compared to a cumulative thyroid cancer risk of 0.12 × 10-5 among the general Nigerian population. CONCLUSIONS: Scanner specifications and technique may significantly contribute to variations seen in thyroid radiation doses. There may be a need to optimise centre protocols and apply dose reference levels for head and neck CT examinations to reduce thyroid cancer risk in Nigeria.

Where COVID-19 testing is challenging: a case series highlighting the role of thoracic imaging in resolving management dilemma posed by unusual presentation.

The COVID-19 pandemic remains an evolving disease posing a challenge of incomplete understanding escalated by random atypical clinical presentations. Numerous challenges still exist with accessibility and availability of standard COVID-19 viral testing using real-time Polymerase Chain Reaction (RT-PCR), in low- and middle-income countries, especially in several hospital settings. The clinical information of three select patients at a major health facility in Southwestern Nigeria with unusual COVID-19 clinical presentation and clinical management dilemma related to challenges with COVID-19 viral laboratory testing, were retrospectively reviewed. The medical history in all three cases closely mimicked that of other medical conditions because of assumptions created by red herrings like an acute exacerbation of an underlying non-communicable disease (diaphragmatic eventration) in case 1, re-activation of a previously treated lung condition (tuberculosis) in case 2 and a sequalae of a previously diagnosed but poorly-managed chronic non-communicable disease (decompensated hypertensive heart disease). Also, viral testing was challenging in all cases due to reasons ranging from late turn-around time to inconsistent results. However, thoracic imaging was employed in all cases to heighten suspicion of COVID-19 infection, resolve management dilemma and limit intra-hospital spread. Thoracic imaging can play a major role within hospital settings in low-and middle-income countries in resolving diagnostic challenges of atypical COVID-19 clinical presentations, raising suspicion for early institution of intra-hospital disease containment measures, limiting exposure among hospital staff and guiding clinical case management of COVID-19; especially where challenges with confirmatory viral testing remain persistent.

Cranial tomographic angiographic evaluation of suspected intracranial vascular abnormalities among a Nigerian cohort

Background: Lately, there has been an increased utilization of computed tomography angiography (CTA) as the preferred first-line modality for the evaluation and diagnosis of most cerebral vascular lesions.Objective: The objective of this study was to evaluate suspected intracranial vascular cases, using CTA at a major referral tertiary hospital in South West Nigeria.Materials and Methods: This was a hospital-based retrospective study of suspected intracranial vascular cases in all ages and both sexes that had CTA from January 2011 to December 2018. Data were analyzed with IBM SPSS version 23.0, and P < 0.005 was considered statistically significant.Results: A total of 128 patients were studied, the mean age was 44.1 ± 17.7 years, and male: female ratio was 1:1.06. The leading clinical diagnoses were as follows: intracranial aneurysms (34/128), subarachnoid hemorrhage (27/128), intracranial vascular tumors (26/128), brain hemorrhage from vascular abnormality (19/128), and arteriovenous malformations (AVMs) (10/128). At CTA, 61 patients had vascular abnormalities: intracranial aneurysm was seen in 63.9% with a peak age range of 41­60 years, and the leading location of aneurysms was posterior cerebral artery (18.8%), followed by posterior communicating artery (16.7%) and the cavernous segment of the internal carotid artery (16.7%). AVMs were more common in patients aged 40 years and below (91.7%) in males (66.7%) and in the parietal lobe. Intracranial aneurysms were 3.25 times as common as brain AVMs.Conclusion: Intracranial aneurysms are the predominant vascular lesions, occurring mostly in the older age group. AVMs occurred mostly in younger people, more in males, and predominantly in the parietal lobes. The hospital incidence of aneurysms to AVMs was 3.25:1

Intima-media thickness of femoral arteries and carotids among an adult hypertensive Nigerian population: A case-control study to assess their use as surrogate markers of atherosclerosis.

Background: Increased intima-media thickness (IMT) is an established and important surrogate marker for atherosclerosis. Intima-media thickening in the femoral arteries occur earlier and reflect the true extent of generalized atherosclerosis better than in the carotids. Aims: To study the ultrasound-detected morphological changes in the common femoral versus carotid artery wall. Patients and Methods: A case-control study design was used, with 61 adult hypertensive as cases and 61 age-, sex- and BMI-matched normotensive as controls. Variables were participants' characteristics, cardiovascular risk factors, and ultrasonographically evaluated IMT of the carotid and femoral arteries. Results: A total of 122 participants were studied. The mean femoral IMT in hypertensives and controls on the right and left was 0.63 ± 0.07mm vs. 0.52 ± 0.06mm [P < 0.0001] and 0.69 ± 0.0 mm vs. 0.55 ± 0.05mm [P < 0.0001]. Also, the mean carotid IMT among hypertensives and controls on the right =0.80 ±0.15mm vs. 0.64 ± 0.06mm [P < 0.0001], and 0.91 ± 0.22mm vs. 0.65 ± 0.06mm [P < 0.0001] on the left. Significant correlation was observed between IMT and age (B = 0.006, P < 0.001 and B = 0.003, P < 0.001), hypertension (B = 0.205, P < 0.001 and B = 0.122, p< 0.001), and duration of hypertension (B = 0.02, P < 0.001 and B = 0.006, P = 0.02) the femoral and carotid arteries respectively. Conclusion: The femoral and the carotid artery show similar significantly increased IMT in hypertensive adults. The femoral IMT appears to be a good surrogate marker of atherosclerosis among hypertensive Nigerians.

RésuméContexte: L'épaisseur accrue de l'intima-média (IMT) est un marqueur de substitution établi et important de l'athérosclérose. L'épaississement intima-média dans les artères fémorales survient plus tôt et reflète mieux l'étendue réelle de l'athérosclérose généralisée que dans les carotides. Objectifs: étudier les modifications morphologiques détectées par échographie dans la paroi de l'artère fémorale commune par rapport à la carotide. Patients et méthodes: Un schéma d'étude cas-témoins a été utilisé, avec 61 adultes hypertensifs en tant qu'études des cas et 61 normo-tensifs appariés pour l'âge, le sexe et l'IMC en tant que contrôles. Les variables étaient les caractéristiques des participants, les facteurs de risque cardiovasculaires et les TMI évaluées par échographie des artères carotides et fémorales. Résultats: Un total de 122 participants ont été étudiés. Le TMI fémoral moyen chez les hypertensifs et chez les témoins de droite et de gauche était de 0,63 ± 0,07 mm contre 0,52 ± 0,06 mm [P <0,0001] et de 0,69 ± 0,0 mm contre 0,55 ± 0,05 mm [P <0,0001]. En outre, la moyenne IMT carotidienne chez les hypertendus et les contrôles à droite = 0,80 ± 0,15 mm vs 0,64 ± 0,06 mm [P <0,0001] et 0,91 ± 0,22 mm contre 0,65 ± 0,06 mm [p < 0,0001] à gauche. Une corrélation significative a été observée entre les TMI et l'âge (B = 0,006, p < 0,001 et B = 0,003, p < 0,001), l'hypertension (B = 0,205, p <0,001 et B = 0,122, p <0,001) et la durée de l'hypertension (B = 0,02, p < 0,001 et B = 0,006, p = 0,02) respectivement des artères fémorale et carotide. Conclusion: Les artères fémorales et carotide montrent une augmentation similaire du TMI chez les adultes hypertensifs. L'IMT fémoral semble être un bon marqueur de substitution de l'athérosclérose chez les Nigérians hypertensifs.

Uterine and umbilical artery doppler in women with pre-eclampsia and their pregnancy outcomes.

BACKGROUND: Pre-eclampsia (PE) is an important public health menace in both developed and developing countries with high maternal and perinatal morbidity and mortality globally. A major goal towards improving antenatal management of PE is to develop accurate prediction models that identify women at high risk of this disease for appropriate interventions. METHODOLOGY: In a longitudinal cohort study, high-risk singleton pregnant women enroled between April 2015 and February 2016 had uterine and umbilical artery Doppler sonography at 22-24 weeks and 32-34 weeks gestation and had their delivery outcomes documented by the obstetrician and gynaecologist. The peak systolic velocity (PSV), end-diastolic velocity (EDV), Resistivity Index (RI), Pulsatility Index (PI) and the systolic-diastolic ratio (S/D) were recorded. RESULTS: Among the ninety-eight high-risk pregnant women, 61 (62.2%) developed PE and 32 (32.8%) did not have PE. In the PE cases, 15 (24.5%) were mild and 46 (74.5%) were severe PE. The uterine artery PI was significantly associated with PE. A unit increase in uterine PI in high-risk pregnancies, increases the odd of PE by 37.37 times (95% confidence interval; odds ratio = 6.09, 241.9; P < 0.001). The combination of the uterine and umbilical PSV predicted 80.3% of severe PE. All three spontaneous abortions were in women who developed PE, more caesarean section (48.4%) and 69.2% of 45 pre-term deliveries occurred in women with severe PE. CONCLUSION: The findings from this study show significantly lower uterine and umbilical arteries PSV and EDV but higher RI, PI and S/D in cases that developed PE. The uterine artery PI is the best predictor of PE, whereas the combinations of uterine and umbilical arteries PSV best predict severity of PE among high-risk pregnant Nigeria women.

Intima-media thickness of femoral arteries and carotids among an adult hypertensive Nigerian population: a case­control study to assess their use as surrogate markers of atherosclerosis

Background: Increased intima-media thickness (IMT) is an established and important surrogate marker for atherosclerosis. Intima-media thickening in the femoral arteries occur earlier and reflect the true extent of generalized atherosclerosis better than in the carotids. Aims: To study the ultrasound-detected morphological changes in the common femoral versus carotid artery wall. Patients and Methods: A case-control study design was used, with 61 adult hypertensive as cases and 61 age-, sex- and BMI-matched normotensive as controls. Variables were participants' characteristics, cardiovascular risk factors, and ultrasonographically evaluated IMT of the carotid and femoral arteries. Results: A total of 122 participants were studied. The mean femoral IMT in hypertensives and controls on the right and left was 0.63 ± 0.07mm vs. 0.52 ± 0.06mm [P < 0.0001] and 0.69 ± 0.0 mm vs. 0.55 ± 0.05mm [P < 0.0001]. Also, the mean carotid IMT among hypertensives and controls on the right =0.80 ±0.15mm vs. 0.64 ± 0.06mm [P < 0.0001], and 0.91 ± 0.22mm vs. 0.65 ± 0.06mm [P < 0.0001] on the left. Significant correlation was observed between IMT and age (B = 0.006, P < 0.001 and B = 0.003, P < 0.001), hypertension (B = 0.205, P < 0.001 and B = 0.122, p<0.001), and duration of hypertension (B = 0.02, P < 0.001 and B = 0.006, P = 0.02) the femoral and carotid arteries respectively. Conclusion: The femoral and the carotid artery show similar significantly increased IMT in hypertensive adults. The femoral IMT appears to be a good surrogate marker of atherosclerosis among hypertensive Nigerians

Maternal ophthalmic artery Doppler velocimetry in pre-eclampsia in Southwestern Nigeria.

BACKGROUND: Pre-eclampsia (PE) poses a serious challenge to maternal and fetal health in Africa. It is associated with hemodynamic changes that may affect the internal carotid/ophthalmic artery circulation with consequent neuro-ophthalmic manifestations. Ophthalmic artery Doppler (OAD) ultrasound is an important tool that can be used to detect hemodynamic changes in PE and monitor its severity. In this study, we evaluated hemodynamic changes on OAD ultrasound in the ophthalmic arteries of pre-eclamptic women and compared these with values in healthy pregnant women. METHODS: OAD parameters, such as, peak systolic velocity, peak diastolic velocity, end diastolic velocity, pulsatility index, and peak ratio, were measured on transorbital triplex ultrasound scan with a 7-10 MHz multifrequency linear transducer in 42 consenting pre-eclamptic patients and 41 pregnant controls matched for maternal age, gestational age, and parity at the Department of Radiology, University College Hospital, Ibadan. Univariate, bivariate, and receiver operating characteristic curve data analyses were performed. P<0.05 was considered to be statistically significant. RESULTS: Mean resistivity index, pulsatility index, and peak systolic velocity were significantly lower in pre-eclamptic patients than in the controls. Mean peak diastolic velocity, end diastolic velocity, and peak ratio were significantly higher in the pre-eclamptic group. The receiver operating characteristic curve showed that the resistivity index (sensitivity 75%, specificity 77.8%) could distinguish mild from severe PE while the peak ratio (sensitivity 90.5%, specificity 81.3%) could accurately detect PE. CONCLUSION: OAD ultrasound can be used to monitor patients with PE for early detection of progression to severe forms before cerebral complications develop. OAD screening of patients at high risk for PE can also detect early changes of hemodynamic derangement.