Safety Survey on Lone Working Magnetic Resonance Imaging Technologists in Saudi Arabia.

PURPOSE: The American College of Radiology (ACR) requires MR personnel not to work alone due to the increased risk of safety issues such as projectiles, aggressive patients, and technologist fatigue. As a result, we intend to assess the current safety of lone-working MRI technologists in MRI departments in Saudi Arabia. MATERIALS AND METHODS: A cross-sectional study using a self-report questionnaire was conducted in 88 Saudi hospitals. RESULTS: A response rate of 64% (174/270) was obtained among the 270 MRI technologists which were identified. The study discovered that 86% of MRI technologists had prior experience working alone. In terms of MRI safety training, 63% of MRI technologists received such training. A question about lone MRI workers' awareness of the ACR's recommendations revealed that 38% were unaware of such recommendations. Furthermore, 22% were misinformed, believing that working alone in an MRI unit is optional or depends on the individual's desire to work alone. Working alone has the primary consequence of being statistically significantly associated with projectile/object-related accidents/mistakes (p = 0.03). CONCLUSION: Saudi Arabian MRI technologists have extensive experience working alone without supervision. Most MRI technologists are unaware of lone working regulations, which has raised concerns about accidents/mistakes. There is a need for MRI safety training and adequate practical experience to raise awareness of MRI safety regulations and policies related to lone working among departments and MRI workers.

Evaluation occupationally radiation exposure during diagnostic imaging examinations.

Occupational radiation exposure can occur due to various human activities, including the use of radiation in medicine. Occupationally exposed personnel surpassing 7.4 millions, and respresent the biggest single group of employees who are exposed to artificial radiation sources at work. This study compares the occupational radiation dose levels for 145 workers in four different hospitals located in the Aseer region in Saudi Arabia. The occupational exposure was quantified using thermoluminescence dosimeters (TLD-100). The levels of annual occupational exposures in targeted hospitals were calculated and compared with the levels of the international atomic energy agency (IAEA) Safety Standards. An average yearly cumulative dose for the two consecutive years. The average, highest and lowest resulted occupational doses under examination in this work is 1.42, 3.9 mSv and 0.72 for workers in various diagnostic radiology procedures. The resulted annual effective dose were within the IAEA approved yearly dose limit for occupational exposure of workers over 18, which is 20 mSv. Staff should be monitored on a regular basis, according to current practice, because their annual exposure may surpass 15% of the annual effective doses.

Estimation of patient effective doses in PET/CT- 18F-Sodium Fluoride examinations.

The positron emitters (18F-Sodium Fluoride (NaF)) and X-rays used in Positron emission tomography (PET) combined with computed tomography (PET/CT) imaging have a high radiation dose, which results in a high patient dose. The present research intends to determine the radiation dose and risks associated with PET/CT- 18F-Sodium fluoride examinations in patients. The 18F-NaF PET/CT was used to investigate the doses of 86 patients. Patient exposure parameters and ImPACT software were used to calculate mean effective doses. The administered activity of 185 MBq (5.0 mCi) per procedure has a mean and range based on the patient's BMI (BMI). The range of patient effective doses per procedure was found to be 4-10 mSv, with a radiation risk of 1 × 10-5 per procedure. Patient doses are determined by the patient's size, scanner type, imaging protocol, and reconstruction method. For further dose reduction, proper justification and radiation dose optimization is required.

Effective radiation doses in pediatric PET/CT examinations: Pilot study.

The young are significantly more sensitive to radiation than adults, by up to 3 times, due to their rapidly dividing cells and anticipation of a relatively longer lifespan. Positron emission tomography (PET)/Computed tomography (CT) plays a major role in the diagnosis of many clinical disorders, albeit with patients being subject to enhanced radiogenic risk from ionizing radiation. The aims of present research are to assess the effective doses during pediatric PET/CT examination using 18F-Sodium fluoride (18F-NaF) and 18F- Fluorodeoxy-d-glucose (18F-FDG) radiotracers. A total of 122 pediatric patients were examined, 78% (95 patients) and 22% (27 patients) undergoing 18F-FDG and 18F-NaF studies, respectively. The patients were scanned using two General Electric (GE) Discovery 710 128 slice PET/CT facilities installed in two tertiary hospitals. Patients were categorized into three age groups: ≤5 years, 6 - ≤10 years and 11 - ≤15 years. Per procedure, the mean cumulative effective doses (in mSv) for 18F-FDG group were 12.1, 10.7 and 12.1 for the three respective age groups. Moreover, the mean cumulative effective doses (in mSv) for 18F-NaF group were 6.8, 6.4 and 7.1 for the same three respective age groups. The cumulative effective doses have been found to be comparable with previous studies.

Measurements of surface air 7Be concentrations in Saudi Arabia.

The main objective of this study is to identify the atmospheric 7Be concentrations in 130 surface air samples collected from three stations located in Riyadh, Haql and Khafji cities in Saudi Arabia between November 2012 and April 2014. Monthly variations as well as seasonal patterns of 7Be were studied using a medium-volume air sampler and a gamma spectroscopy system equipped with a high-purity germanium (HPGe) detector. 7Be exhibited one maximum specific activity in summer and one minimum in winter with average monthly concentrations of 12.4 ± 0.9, 15.4 ± 1.2, and 18.0 ± 1.3 mBq m-3 in Riyadh, Haql and Khafji, respectively. Overall, the average 7Be concentration in the three stations was 12.9 ± 1.0 mBq m-3, whereas the maximum value of 29.5 mBq m-3 was registered in Khafji city in August 2013. Besides 7Be, measurements indicate observations of 40 K, 137Cs, 226Ra radionuclides in surface air samples collected from the three stations. 40 K showed measurable concentrations, whereas the concentrations of 137Cs and 226Ra were only detected in a limited number of samples.

Multifunctional, biocompatible and pH-responsive carbon nanotube- and graphene oxide/tectomer hybrid composites and coatings.

Here we present a route for non-covalent functionalization of carboxylated multi-walled carbon nanotubes and graphene oxide with novel two-dimensional peptide assemblies. We show that self-assembled amino-terminated biantennary and tetraantennary oligoglycine peptides (referred to as tectomers) effectively coat carboxylated multi-walled carbon nanotubes and also strongly interact with graphene oxide due to electrostatic interactions and hydrogen bonding as the driving force, respectively. The resulting hybrids can be made into free-standing conducting composites or applied in the form of thin, pH-switchable bioadhesive coatings onto graphene oxide fibers. Monitoring of cell viability of pancreatic cell lines, seeded on those CNT hybrids, show that they can be used as two- and three-dimensional scaffolds to tissue engineer tumour models for studying ex vivo the tumour development and response to treatment. This highly versatile method in producing pH-responsive hybrids and coatings offers an attractive platform for a variety of biomedical applications and for the development of functional materials such as smart textiles, sensors and bioelectronic devices.

Carbon nanotubes buckypaper radiation studies for medical physics applications.

Graphite ion chambers and semiconductor diode detectors have been used to make measurements in phantoms but these active devices represent a clear disadvantage when considered for in vivo dosimetry. In such circumstance, dosimeters with atomic number similar to human tissue are needed. Carbon nanotubes have properties that potentially meet the demand, requiring low voltage in active devices and an atomic number similar to adipose tissue. In this study, single-wall carbon nanotubes (SWCNTs) buckypaper has been used to measure the beta particle dose deposited from a strontium-90 source, the medium displaying thermoluminescence at potentially useful sensitivity. As an example, the samples show a clear response for a dose of 2Gy. This finding suggests that carbon nanotubes can be used as a passive dosimeter specifically for the high levels of radiation exposures used in radiation therapy. Furthermore, the finding points towards further potential applications such as for space radiation measurements, not least because the medium satisfies a demand for light but strong materials of minimal capacitance.

Favorable therapeutic response of osteoporosis patients to treatment with intravenous zoledronate compared with oral alendronate.

OBJECTIVES: To evaluate the efficacy of orally-administered alendronate compared with intravenously-administered zoledronate. METHODS: This prospective study was carried out at Barts Health HNS Trust between April 2010 and March 2012. This study compares changes in bone mineral density (BMD) in 234 patients treated with 2 bisphosphonates: alendronate taken orally, and zoledronate administered intravenously. One hundred and eighteen patients received alendronate at 70 mg/week, while 116 patients received zoledronate once annually. Dual energy x-ray absorptiometry was used to measure BMD of the left hip and anterior-posterior spine (lumbar L1-L4) skeletal sites at baseline, and at one-, and 2-years post-treatment. RESULTS: This study provides evidence that lumbar spine BMD increased by 3.6% in patients receiving alendronate, and 5.7% in patients receiving zoledronate after 2 years compared with baseline values (p=0.0001 for both). Total hip BMD decreased in patients treated with alendronate by 0.4% but increased in patients receiving zoledronate by 0.8% (p=0.0001). CONCLUSION: This study provides evidence that zoledronate is more effective than alendronate in treating patients with osteoporosis and with no gastrointestinal (GI) serious side effects. Furthermore, zoledronate appears to have the added advantage of a better safety profile in patients suffering from GI intolerance of oral bisphosphonates.

"To-and-fro" waveform in the diagnosis of arterial pseudoaneurysms.

Medical ultrasound imaging with Doppler plays an essential role in the diagnosis of vascular disease. This study intended to review the clinical use of "to-and-fro" waveform at duplex Doppler ultrasonography (DDU) in the diagnosis of pseudoaneurysms in the arterial vessels of upper and lower extremities, abdominal aorta, carotid and vertebral arteries as well as to review our personal experiences of "to-and-fro" waveform at DDU also. After receiving institutional review board approval, an inclusive literature review was carried out in order to review the scientific foundation of "to-and-fro" waveform at DDU and its clinical use in the diagnosis of pseudoaneurysms in various arterial vessels. Articles published in the English language between 2000 and 2013 were evaluated in this review study. Pseudoaneurysms in arterial vessels of the upper and lower extremities, abdominal aorta, carotid and vertebral arteries characterized by an extraluminal pattern of blood flow, which shows variable echogenicity, interval complexity, and "to-and-fro" flow pattern on color Doppler ultrasonography. In these arterial vessels, Duplex ultrasonography can demonstrate the degree of clotting, pseudoaneurysm communication, the blood flow patterns and velocities. Spectral Doppler applied to pseudoaneurysms lumen revealed systolic and diastolic turbulent blood flow with traditional "to-and-fro" waveform in the communicating channel. Accurate diagnosis of pseudoaneurysm by spectral Doppler is based on the documentation of the "to-and-fro" waveform. The size of pseudoaneurysm determines the appropriate treatment approach as surgical or conservative.

High-Intensity Focused Ultrasound (HIFU) in Localized Prostate Cancer Treatment.

BACKGROUND: High-intensity focused ultrasound (HIFU) applies high-intensity focused ultrasound energy to locally heat and destroy diseased or damaged tissue through ablation. This study intended to review HIFU to explain the fundamentals of HIFU, evaluate the evidence concerning the role of HIFU in the treatment of prostate cancer (PC), review the technologies used to perform HIFU and the published clinical literature regarding the procedure as a primary treatment for PC. MATERIAL/METHODS: Studies addressing HIFU in localized PC were identified in a search of internet scientific databases. The analysis of outcomes was limited to journal articles written in English and published between 2000 and 2013. RESULTS: HIFU is a non-invasive approach that uses a precisely delivered ultrasound energy to achieve tumor cell necrosis without radiation or surgical excision. In current urological oncology, HIFU is used clinically in the treatment of PC. Clinical research on HIFU therapy for localized PC began in the 1990s, and the majority of PC patients were treated with the Ablatherm device. CONCLUSIONS: HIFU treatment for localized PC can be considered as an alternative minimally invasive therapeutic modality for patients who are not candidates for radical prostatectomy. Patients with lower pre-HIFU PSA level and favourable pathologic Gleason score seem to present better oncologic outcomes. Future advances in technology and safety will undoubtedly expand the HIFU role in this indication as more of patient series are published, with a longer follow-up period.

High-Intensity Focused Ultrasound (HIFU) in Uterine Fibroid Treatment: Review Study.

BACKGROUND: High-intensity focused ultrasound (HIFU) is a highly precise medical procedure used locally to heat and destroy diseased tissue through ablation. This study intended to review HIFU in uterine fibroid therapy, to evaluate the role of HIFU in the therapy of leiomyomas as well as to review the actual clinical activities in this field including efficacy and safety measures beside the published clinical literature. MATERIAL/METHODS: An inclusive literature review was carried out in order to review the scientific foundation, and how it resulted in the development of extracorporeal distinct devices. Studies addressing HIFU in leiomyomas were identified from a search of the Internet scientific databases. The analysis of literature was limited to journal articles written in English and published between 2000 and 2013. RESULTS: In current gynecologic oncology, HIFU is used clinically in the treatment of leiomyomas. Clinical research on HIFU therapy for leiomyomas began in the 1990s, and the majority of patients with leiomyomas were treated predominantly with HIFUNIT 9000 and prototype single focus ultrasound devices. HIFU is a non-invasive and highly effective standard treatment with a large indication range for all sizes of leiomyomas, associated with high efficacy, low operative morbidity and no systemic side effects. CONCLUSIONS: Uterine fibroid treatment using HIFU was effective and safe in treating symptomatic uterine fibroids. Few studies are available in the literature regarding uterine artery embolization (UAE). HIFU provides an excellent option to treat uterine fibroids.

Preliminary Monte Carlo study of (18)F-FDG SPECT imaging with LaBr(3):Ce Crystal-based Gamma Cameras.

The utility of (18)F-deoxyglucose ((18)F-FDG) in oncology, cardiology, and neurology has generated great interest in a more economical ways of imaging (18)F-FDG than conventional PET scanners. The main thrust of this work is to investigate the potential use of LaBr(3):Ce materials in a low-cost FDG-SPECT system compared to NaI(Tl) using GATE Monte Carlo simulation. System performance at 140 keV and 511 keV was assessed using energy spectra, system sensitivity and count rate performance. Comparison of the LaBr(3):Ce and NaI(Tl) crystal-based systems showed 4.5% and 8.9% higher system sensitivity for the LaBr(3):Ce at 140 keV and 511 keV, respectively. The LaBr(3):Ce scintillator significantly improves intrinsic count rate performance due to its fast decay time with respect to NaI(Tl). In conclusion, because LaBr(3):Ce crystal combines excellent intrinsic count rate performance with slightly increased system sensitivity, it has the potential to be used for (18)F-FDG -SPECT systems.