A Microwave Imaging Procedure for Lung Lesion Detection: Preliminary Results on Multilayer Phantoms

In this work, a feasibility study for lung lesion detection through microwave imaging based on Huygens’ principle (HP) has been performed using multilayer oval shaped phantoms mimicking human torso having a cylindrically shaped inclusion simulating lung lesion. First, validation of the proposed imaging method has been performed through phantom experiments using a dedicated realistic human torso model inside an anechoic chamber, employing a frequency range of 1–5 GHz. Subsequently, the miniaturized torso phantom validation (using both single and double inclusion scenarios) has been accomplished using a microwave imaging (MWI) device, which operates in free space using two antennas in multi-bistatic configuration. The identification of the target’s presence in the lung layer has been achieved on the obtained images after applying both of the following artifact removal procedures: (i) the “rotation subtraction” method using two adjacent transmitting antenna positions, and (ii) the “ideal” artifact removal procedure utilizing the difference between received signals from unhealthy and healthy scenarios. In addition, a quantitative analysis of the obtained images was executed based on the definition of signal to clutter ratio (SCR). The obtained results verify that HP can be utilized successfully to discover the presence and location of the inclusion in the lung-mimicking phantom, achieving an SCR of 9.88 dB

Free space operating microwave imaging device for bone lesion detection: a phantom investigation

In this letter, a phantom validation of a low complexity microwave imaging device operating in free space in the 1-6.5 GHz frequency band is presented. The device, initially constructed for breast cancer detection, measures the scattered signals in a multi-bistatic fashion and employs an imaging procedure based on Huygens principle. Detection has been achieved in both bone fracture lesion and bone marrow lesion scenarios using the superimposition of five doublet transmitting positions, after applying the rotation subtraction artefact removal method. A resolution of 5 mm and a signal to clutter ratio (3.35 in linear scale) are achieved confirming the advantage of employing multiple transmitting positions on increased detection capability

Developing Artefact Removal Algorithms to Process Data from a Microwave Imaging Device for Haemorrhagic Stroke Detection

In this paper, we present an investigation of different artefact removal methods for ultra-wideband Microwave Imaging (MWI) to evaluate and quantify current methods in a real environment through measurements using an MWI device. The MWI device measures the scattered signals in a multi-bistatic fashion and employs an imaging procedure based on Huygens principle. A simple two-layered phantom mimicking human head tissue is realised, applying a cylindrically shaped inclusion to emulate brain haemorrhage. Detection has been successfully achieved using the superimposition of five transmitter triplet positions, after applying different artefact removal methods, with the inclusion positioned at 0°, 90°, 180°, and 270°. The different artifact removal methods have been proposed for comparison to improve the stroke detection process. To provide a valid comparison between these methods, image quantification metrics are presented. An “ideal/reference” image is used to compare the artefact removal methods. Moreover, the quantification of artefact removal procedures through measurements using MWI device is performed

Evaluation of fluconazole effect in prevention of fungal infection and mortality and morbidity in very low-birth-weight infants

Background: Fungal infections especially Candida species are frequent cause of mortality and morbidity in very low-birth-weight (VLBW) infants receiving intensive care; Candida infections are tissue invasive. This infection increases the risks of adverse neurodevelopmental sequelae. Prevention and treatment of fungal infection is so important in very VLBW infants. The aim of this study was to determine the prophylactic effect of fluconazole in decreasing the mortality and morbidity in VLBW infants (less than 1500gr) admitted in NICU. Methods: This prospective case control study were conducted among 102 Infants (weighing less than 1500gr at birth at born) admitted in NICU department of Ali Asghar University Hospital from 2012 to 2013, Tehran, Iran. Weigh of birth in cases and groups were less than 1500 gr and both were culture negative. Cases received oral fluconazole 3 mg/kg in 3 days in 1st and 2nd weeks, alternate day in 3rd and 4th weeks, daily in 5th and 6th weeks. Control groups had not received fluconazole. Mortality and morbidity and hospital stay were compared between cases and controls groups. Results: We studied 49 very low-birth-weight infants with negative culture as cases (received fluconazole prophylaxis), 46 VLBW infants without fluconazole profilaxy (controls). No significant difference in gestational age (P=0.2), and mean weights (P=0.4) were observed between cases and controls. The mortality rate 8.7 (n=4) in controls (without prophylactic fluconazole) observed vs 2 (n=1) mortality rate in VLBW cases (with prophylactic fluconazole). Although the mortality rate in controls was 4 times higher than cases, but without significant differences (P=0.1). Indeed, mean duration of hospital stay in controls was longer than cases (28.41±9.93 vs 19.85±6.19 days, P=0.00001). Conclusion: Although prophylactic fluconazole in VLBW could decrease the mortality of cases (control the fungal infection) 4 fold in compare with controls (no treatment), it was not significant. The prophylactic effect of fluconazole might decrease the length of hospital stay of VLBW neonates in NICU. Due to limited number of cases and control. For further decision about prophylactic use of fluconazole, prospective RCT studies with larger cases and control would be helpful in future. © 2016, Tehran University of Medical Sciences. All rights reserved

Situational analysis of essential surgical care management in Iran using the WHO tool

Background: Surgery is an essential component of health care, yet it has usually been overlooked in public health across the world. Objectives: This study aimed to perform a situational analysis of essential surgical care management at district hospitals in Iran. Materials and Methods: This research was a descriptive and cross-sectional study performed at 42 first-referral district hospitals of Iran in 2013. The World Health Organization (WHO) Tool for the situational analysis of emergency and essential care was used for data collection in four domains of facilities and equipment, human resources, surgical interventions, and infrastructure. Data analysis was conducted using simple descriptive statistical methods. Results: In this study, 100 of the studied hospitals had oxygen cylinders, running water, electricity, anesthesia machines, emergency departments, archives of medical records, and X-ray machines. In 100 of the surveyed hospitals, specialists in surgery, anesthesia, and obstetrics and gynecology were available as full-time staff. Life-saving procedures were performed in the majority of the hospitals. Among urgent procedures, neonatal surgeries were conducted in 14.3 of the hospitals. Regarding non-urgent procedures, acute burn management was conducted in 38.1 of the hospitals. Also, a few other procedures such as cricothyrotomy and foreign body removal were performed in 85.7 of the hospitals. Conclusions: The results indicated that suitable facilities and equipment, human resources, and infrastructure were available in the district hospitals in Iran. These findings showed that there is potential for the district hospitals to provide care in a wider spectrum. © 2016, Iranian Red Crescent Medical Journal

3D Huygens Principle based Microwave Imaging through MammoWave Device: Validation through Phantoms.

This work focuses on developing a 3D microwave imaging (MWI) algorithm based on the Huygens principle (HP). Specifically, a novel, fast MWI device (MammoWave) has been presented and exploited for its capabilities of extending image reconstruction from 2D to 3D. For this purpose, dedicated phantoms containing 3D structured inclusion have been prepared with mixtures having different dielectric properties. Phantom measurements have been performed at multiple planes along the z-axis by simultaneously changing the transmitter and receiver antenna height via the graphic user interface (GUI) integrated with MammoWave. We have recorded the complex S21 multi-quote data at multiple planes along the z-axis. The complex multidimensional raw data has been processed via an enhanced HP-based image algorithm for 3D image reconstruction. This paper demonstrates the successful detection and 3D visualization of the inclusion with varying dimensions at multiple planes/cross-sections along the z-axis with a dimensional error lower than 7.5%. Moreover, the paper shows successful detection and 3D visualization of the inclusion in a skull-mimicking phantom having a cylindrically shaped inclusion, with the location of the detected inclusion in agreement with the experimental setup. Additionally, the localization of a 3D structured spherical inclusion has been shown in a more complex scenario using a 3-layer cylindrically shaped phantom, along with the corresponding 3D image reconstruction and visualization

Nosocomial infection in an Iranian neonatal intensive care unit: Hospital epidemiology and risk factors

Background: Hospital-acquired infection is one of the main concerns in Neonatal Intensive Care Units (NICUs), leading to increased mortality, hospital stay, and costs. Objectives: This study aimed to investigate the risk factors of hospital-acquired infection in NICUs. Methods: A descriptive, cross-sectional, prospective study was conducted in the NICU of Ali Asghar Children Hospital for one year. All admitted newborns were sampled on a simple basis. The criteria for the diagnosis of hospital-acquired infection were based on the definitions of the CDC and the NNIS system. Risk factors such as days of fully catheters usage, nurse-to-patient ratio, history of surgery, prematurity, and mechanical ventilation were considered as variables. The data collection tools consisted of a patient information questionnaire, the monthly report of the hospital infection control committee based on the NNIS system, a daily schedule of all risk factors for each infant, and the monthly nurse-to-patient ratio in the NICU. The STATA software was used for data analysis. Results: In our study, 654 newborns were enrolled. The rate of hospital-acquired infections was 13.5. Moreover, 80.7 of the cases exhibited sepsis (72.7 diagnosed based on clinical findings and 8 based on positive blood culture). Statistical analysis showed 9 pneumonia cases, 8 surgical site infection cases, and 2.3 urinary tract infection cases. The average time to the occurrence of hospital-acquired infection was 13.5 days after admission. All risk factors were significantly higher in the infected group than in the control group (P = 0.0001). Furthermore, surgical interventions were significantly more in the infected group than in the non-infected group (34.1 vs. 6.7, respectively, P = 0.0001). The prevalence rates in different weight ranges (less than 1000 g, 1001 to 1500 g, 1501 to 2500, and above 2501 g) were 2.6, 6.9, 21.4, and 69.1, respectively, in the infected group, which were significantly different from those of the non-infected group (P = 0.0001). The most common etiologic microorganism was Acinetobacter baumannii. Conclusions: Factors such as surgery, the presence of a central venous catheter, and the increased length of hospital stay significantly increased the hospital-acquired infections. Reducing invasive procedures, maintenance of full catheters, and providing optimal nursing care can help control hospital-acquired infections. © 2020, Author(s)

Comparison of risk factors related to intraventricular hemorrhage between preterm infants born after normal and in vitro fertilization conceptions

Objectives We aimed to compare the level of significance of risk factors related Intraventricular hemorrhage (IVH) between preterm infants born after IVF and non-IVF conceptions. Materials & Methods This historical cohort study was done in four Iranian Hospitals in 2013-2014. Overall, 155 preterm newborns were divided into case (IVF) and control (normal conception) groups. Both groups� demographic data were extracted and recorded. The incidence of IVH and its grades were compared between case and control groups. Significant related risk factors were also considered. Results No differences were observed between 2 groups except for gestational age and mode of delivery. The incidence of IVH especially grades II and III were significantly higher in the case group (P=0.003). Results showed no correlations between Gestational age (GA), birth weight and number of gestations with the incidence of IVH in the case group (0.059, 0.85 and 0.49, respectively). On the other hand, among GA, birth weight and number of gestations; multi gestations (P=0.0001) was an effective risk factor for IVH occurrence in the controls. Conclusion The incidence of IVH in the IVF group was significantly higher than in the non-IVF group. IVF as an independent risk factor may cause high-grade IVH; however, in the controls, multi gestational pregnancy (P=0.0001) was an effective risk factor for IVH occurrence. © 2019, Iranian Child Neurology Society. All rights reserved