Papers by Uchechukwu Nwadike
Journal of X-ray Science and Technology, May 25, 2018
BACKGROUND: There is abundant quartz deposit in Nigeria which has been used for export and buildi... more BACKGROUND: There is abundant quartz deposit in Nigeria which has been used for export and building purposes. However, its electrical and piezoelectric properties have not been studied. Thus, whether it can be used as raw material for the indigenous electric industries is unknown to date. OBJECTIVE: This study aims to characterize the piezoelectric properties of smoky quartz for ultrasonic transducer and determine its sonic properties. METHOD: In the research approach, the raw quartz was cut into six crystals of rectangular shape using a universal cutter. The crystals were purified with a 100 ml hydrofluoric and hydrochloric acid solution under a temperature of 250 • C in a furnace. The sizes, weights, and capacitance of crystals were determined using the standard measuring instruments. The resonance method was used for the determination of the frequency of minimum and maximum impedance of the crystals. The piezoelectric constants of the crystals were derived using the standard formula for determination of piezoelectric constants. RESULTS: The results show that the sonic properties represented by the piezoelectric charge constant (d 31) and the piezoelectric voltage constant (g31) values are 2.52(±1.075) × 10 −8 c/m 2 and 1030.6114 ± 250.89v/m 2 respectively. CONCLUSION: The present study has characterized Nigerian quartz for its piezoelectric properties and found that it was suitable for use in the construction of ultrasonic transducers.
African Health Sciences, Jan 5, 2018
Objectives: The study was to classify lesions identified on mammograms using Breast Imaging Repor... more Objectives: The study was to classify lesions identified on mammograms using Breast Imaging Reporting and Data System (BI-RADS) grading method. This was in view of ascertaining the rate of occurrence of breast malignancy of the studied population. Methods: A retrospective cohort study of 416 mammographic reports of women was undertaken. The reports were written by consultant radiologists of 10 years' experience and above. The reports were evaluated and characterised using Breast Imaging Reporting and Data system (BIRADS). Demographic data of patients were sourced from the request cards. The data was entered into a proforma and analysed using SPSS version 17. All request cards with incomplete data were excluded from the study. Results: Using the BI-RADS Classification, the mammographic reports shows that 29.57% of the lesions were benign, and 4.57% were suspicious and biopsy recommended, while 3.60% were highly suggestive of malignancy. The right breast was predominantly affected with 42.7% of the patients (P<0.05). Conclusion: Classification of breast lesion using BI-RADS grading system is a veritable tool in the diagnosis of the breast lesion. The present study shows that 3.6% of the population has a high index of malignancy.
The West Indian medical journal, 2015
Objective The objective of this study was to develop a sonographic technique for the measurement ... more Objective The objective of this study was to develop a sonographic technique for the measurement of fetal interorbital distance (IOD) for gestational age (GA) determination and to establish a normogram of IOD for the local population. Methods The fronto-transverse sonographic technique was established as a feasible and reproducible technique for IOD measurement. Two independent and experienced sonographers tested the technique and had a coefficient of variation of 17.64% and 19.72%, respectively, which is statistically insignificant. The established technique was used to measure the IOD of 320 fetuses from the 13th week to 40th week GA, while standard technique was used to measure biparietal diameter (BPD), head circumference (HC) and femur length (FL) of the fetuses. The data obtained were used to determine the regression equation GA = 6.24 + 4.89 IOD for the prediction of the gestational age. Results There was good correlation between IOD, BPD, HC and FL. The predicted normogram o...
Journal of X-Ray Science and Technology, 2018
BACKGROUND: There is abundant quartz deposit in Nigeria which has been used for export and buildi... more BACKGROUND: There is abundant quartz deposit in Nigeria which has been used for export and building purposes. However, its electrical and piezoelectric properties have not been studied. Thus, whether it can be used as raw material for the indigenous electric industries is unknown to date. OBJECTIVE: This study aims to characterize the piezoelectric properties of smoky quartz for ultrasonic transducer and determine its sonic properties. METHOD: In the research approach, the raw quartz was cut into six crystals of rectangular shape using a universal cutter. The crystals were purified with a 100 ml hydrofluoric and hydrochloric acid solution under a temperature of 250 • C in a furnace. The sizes, weights, and capacitance of crystals were determined using the standard measuring instruments. The resonance method was used for the determination of the frequency of minimum and maximum impedance of the crystals. The piezoelectric constants of the crystals were derived using the standard formula for determination of piezoelectric constants. RESULTS: The results show that the sonic properties represented by the piezoelectric charge constant (d 31) and the piezoelectric voltage constant (g31) values are 2.52(±1.075) × 10 −8 c/m 2 and 1030.6114 ± 250.89v/m 2 respectively. CONCLUSION: The present study has characterized Nigerian quartz for its piezoelectric properties and found that it was suitable for use in the construction of ultrasonic transducers.
African Health Sciences, 2018
Objectives: The study was to classify lesions identified on mammograms using Breast Imaging Repor... more Objectives: The study was to classify lesions identified on mammograms using Breast Imaging Reporting and Data System (BI-RADS) grading method. This was in view of ascertaining the rate of occurrence of breast malignancy of the studied population. Methods: A retrospective cohort study of 416 mammographic reports of women was undertaken. The reports were written by consultant radiologists of 10 years' experience and above. The reports were evaluated and characterised using Breast Imaging Reporting and Data system (BIRADS). Demographic data of patients were sourced from the request cards. The data was entered into a proforma and analysed using SPSS version 17. All request cards with incomplete data were excluded from the study. Results: Using the BI-RADS Classification, the mammographic reports shows that 29.57% of the lesions were benign, and 4.57% were suspicious and biopsy recommended, while 3.60% were highly suggestive of malignancy. The right breast was predominantly affected with 42.7% of the patients (P<0.05). Conclusion: Classification of breast lesion using BI-RADS grading system is a veritable tool in the diagnosis of the breast lesion. The present study shows that 3.6% of the population has a high index of malignancy.
Radiography, 2016
ABSTRACT
African Health Sciences, 2015
Background: Regional variations in size and parenchyma echo-texture of the spleen among sickle ce... more Background: Regional variations in size and parenchyma echo-texture of the spleen among sickle cell disease (SCD) patients have been documented in various publications. The objectives of this study were to assess the size and parenchyma echo-texture of the spleen of SCD patients and ascertain the relationship of age, height and weight with the spleen sizes. Methods: This was a cross sectional study involving 103 each of SCD and age matched control subjects. Aloka ST-550-3500 ultrasound machine with 3.5 and 5 MHz convex transducers was used to scan the subjects over a 15 months period (September, 2012 to November, 2013). The age, height and weight of each subject were recorded. Results: The spleen sizes of SCD patients were generally larger than those of the controls (p < 0.05). Abnormal spleen parenchyma of varied appearances was found among the SCD subjects. There were negative correlations between mean spleen sizes and height, weight and age in SCD patients but positive correlations were found between them in the controls. Conclusion: Routine sonographic assessment of spleen size and echo-texture is useful in the management of SCD patients.
African Health Sciences, 2015
Background: Accuracy of some ultrasound equations used in our locality for fetal weight estimatio... more Background: Accuracy of some ultrasound equations used in our locality for fetal weight estimation is doubtful. Objective: To assess the accuracy of common ultrasound equations used for fetal weight estimation. Subjects and Methods: A longitudinal study was conducted on selected Nigerian obstetric population at Central Hospital, Kwale between March, 2009 and January, 2011. Sonography was performed on 412 women with advanced singleton cyesis and measurements of BPD, HC, AC, and FL were obtained and figured into 12 common ultrasound equations for the estimation of fetal weight. The actual birth weight at delivery was recorded. Results: The highest intraclass correlation coefficient was generated by the Hadlock 5 and Hsieh 2 equations. The least mean absolute percent error was obtained with Hsieh 2 equation, followed by Woo 3, and Hadlock 5. These equations also had the least percentage error and the least range of limits of agreement in the same order with no significant difference between their mean fetal weight estimates and that of the actual birth weight (p > 0.05). All twelve equations had strong positive correlation with the actual birth weight with Nzeh 2 equation the least. Conclusion: Hsieh 2 equation has the best accuracy in fetal weight estimation studied.
African Health Sciences, 2013
Background: Uterine myomas co-existing with pregnancy could cause obstetric complications. Object... more Background: Uterine myomas co-existing with pregnancy could cause obstetric complications. Objectives: To assess sonographically the frequency of occurrence and effect of uterine myomas co-existing with pregnancy. Methods: A longitudinal study was conducted during a period of 23 months. A convenience sample of 816 consecutive consenting pregnant women who met the inclusion criteria was evaluated during routine prenatal ultrasound scan. The women were referred for prenatal sonography. One hundred of the subjects who had myoma co-existing with pregnancy and another 100 subjects without myoma were selected for follow-up. These groups were followed up till delivery and obstetric complications and outcomes were documented. Any changes in size and growth rate of myoma were documented. Results: Subjects with myoma co-existing with pregnancy were 12.3%. This was commoner with increasing maternal age. An increase was observed in myoma mean size from 60mm to 63mm from the 1 st scan sequence to the 2 nd scan sequence and a reduction from 63mm to 59mm in the 3 rd scan sequence. Myoma growth rate was 0.667mm per week. Myomas in pregnancy especially large ones caused more complications during delivery when compared to pregnancies without myomas. Conclusion: Routine sonography is important in pregnancy management of uterine myomas co-existing with pregnancy.
Journal of Diagnostic Medical Sonography, 2017
This study aimed to establish reference values of fetal transverse cerebellar diameter (TCD) in a... more This study aimed to establish reference values of fetal transverse cerebellar diameter (TCD) in a Nigerian population. A cross-sectional convenience study was carried out between June 2013 and May 2014 in Enugu, Nigeria. The sonographic examinations were performed on 697 pregnant women with gestational ages between 14 and 40 weeks. The TCD measurements were obtained from the proximal outer margin to the distal outer margin of cerebellum. The women’s last menstrual period, femur length, biparietal diameter, head circumference, and abdominal circumference were also recorded. The mean (standard deviation) TCD increased from 13.6 (2.2) mm to 27.3 (2.6) mm and 28.9 (2.0) mm to 42.9 (2.0) mm in the second and third trimesters, respectively. The relationship of TCD with gestational age obtained from last menstrual period, femur length, biparietal diameter, head circumference, and abdominal circumference was determined. The TCD had a strong correlation with gestational age ( r = .93; P <...
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Papers by Uchechukwu Nwadike