Reporting Diagnostic Reference Levels for Paediatric Patients Undergoing Brain Computed Tomography.

Brain computed tomography (CT) is a diagnostic imaging tool routinely used to assess all paediatric neurologic disorders and other head injuries. Despite the continuous development of paediatric CT imaging, radiation exposure remains a concern. Using diagnostic reference levels (DRLs) helps to manage the radiation dose delivered to patients, allowing one to identify an unusually high dose. In this paper, we propose DRLs for paediatric brain CT examinations in Saudi clinical practices and compare the findings with those of other reported DRL studies. Data including patient and scanning protocols were collected retrospectively from three medical cities for a total of 225 paediatric patients. DRLs were derived for four different age groupings. The resulting DRL values for the dose-length product (DLP) for the age groups of newborns (0-1 year), 1-y-old (1-5 years), 5-y-old (5-10 years) and 10-y-old (10-15 years) were 404 mGy cm, 560 mGy cm, 548 mGy cm, and 742 mGy cm, respectively. The DRLs for paediatric brain CT imaging are comparable to or slightly lower than other DRLs due to the current use of dose optimisation strategies. This study emphasises the need for an international standardisation for the use of weight group categories in DRL establishment for paediatric care in order to provide a more comparable measurement of dose quantities across different hospitals globally.

Neuroprotective potential of Cordia dichotoma in Parkinson's syndrome induced by haloperidol: An animal study.

Background: Parkinson's disease (PD) is one of the major neurodegenerative disorders and the prevalence is expected to increase during the next couple of decades. There is a need for safe and effective therapeutic regimen that can effectively manage this neurotoxicity. The leaves and several other parts of Cordia dichotoma are known to possess number of medicinal properties. The purpose of this study was to examine the neuroprotective role of Cordia dichotoma in an experimental model of haloperidol-induced P.D. Materials and methods: Five groups of rats were randomly assigned into different groups. Intraperitoneal haloperidol 1 mg/kg was given to the inducer group and 0.5% CMC to the normal control. The reference standard was syndopa 10 mg/kg, p.o., and the test group animals received C. dichotoma's ethanolic extract at 200 and 400 mg/kg orally for one week. Rats exposed to haloperidol were assessed for behavioral, neurochemical, and histopathological parameters. Results: C. dichotoma leaves extract dose-dependently increased behavioral activity and muscle coordination. The extract at 400 mg/kg was found to increase significantly (P < 0.001) the central square activity in open-field test, compared to haloperidol treated rats. In stepping test, both tested doses of C. dichotoma (200 mg and 400 mg/kg) were found to significantly (P < 0.001) reduce akinesia, besides these doses also decreased the catatonic responses induced by haloperidol. Further, the extraction treatment (200 mg and 400 mg/kg) significantly (P < 0.001) decreased malonaldehyde and increased antioxidant enzymes like catalase compared to the control group. Histopathological changes in the test group showed a significant reduction in haloperidol damage to normal morphology in cortical, hippocampus, substantia nigra, and pyramidal. Conclusion: The observations of the study suggest that Cordia dichotoma attenuated the haloperidol-induced neurological changes, indicating that the plant might benefit in the treatment of Parkinson's disease. The activity of Cordia dichotoma could be linked to its antioxidant property. Since, the drug is traditionally used in different parts of world; it could be a promising agent if more research establishes its safety and efficacy in other experimental models of Parkinson's Disease.

Multiple Brown Tumors in Primary Hyperparathyroidism Causing Pathological Fracture: A Case Report of a 21-Year-Old Adult Male.

Multiple brown tumors are more common in females and older age groups and an unlikely site is the long bones. We report a case of a 21-year-old male presenting with a pathological fracture at the left neck of the femur. Laboratory investigations showed elevated parathyroid hormone (PTH) and serum calcium levels (PTH-dependent hypercalcemia). A CT scan revealed multiple osteolytic lesions in the pelvis and femurs, and a Tc-99m sestamibi scan showed a solitary parathyroid adenoma. We demonstrate this rare case and illustrate the importance of the consideration of multiple brown tumors in young males presenting with multiple osteolytic lesions at the long bones in the differential diagnosis. Every physician needs to have a high clinical suspicion of primary hyperparathyroidism innovation, in those who present with osteolytic lesions, with respect to the patient's age and gender.

Prevalence and Correlation of Metabolic Syndrome in Patients with Bipolar Disorder in NGHA, Riyadh.

Background: Metabolic syndrome is considered dangerous, especially to patients that are diagnosed with a mental condition such as bipolar disorder, since these types of patients can be difficult to deal with. Metabolic syndrome can lead to multiple cardiovascular diseases, strokes, and diabetes. A careful approach is important when it comes to facing a complex condition such as this. This research will contribute to giving more information about the prevalence and statistics of metabolic syndrome in bipolar disorder patients at NGHA, Riyadh. No published study in literature has investigated the prevalence of metabolic syndrome in patients with bipolar disorder in NGHA, Riyadh. Methods: The study was conducted among 191 adult male (66) and female (125) patients at NGHA, Riyadh. The medical records were used for the assessment of metabolic syndrome and referrals by using a chart review for individuals. The main variables are metabolic syndrome and bipolar disorder. It was conducted on both males and females. Data was collected on data collection form and further analysis on relations was made by using SAS (Version 9.4). Chi-squared test and the Wilcoxon Two-sample test for two-level continuous variables. P ≤ 0.05 was determined to be the significance level. Results: Out of 191 patients, 130 were obese, 85 had diabetes, and 89 were hypertensive. Additionally, 50 (40%) females and 29 (43.9%) males had metabolic syndrome, a total of 79 (41.4%) out of 191. Conclusion: The findings of this study indicate that there is an elevated prevalence of metabolic syndrome in bipolar disorder patients in NGHA, Riyadh. Highlighting the potential danger that people may not be aware of.

Optimization of computed tomography pulmonary angiography protocols using 3D printed model with simulation of pulmonary embolism.

BACKGROUND: Three-dimensional (3D) printing has been shown to accurately replicate anatomical structures and pathologies in complex cardiovascular disease. Application of 3D printed models to simulate pulmonary arteries and pulmonary embolism (PE) could assist development of computed tomography pulmonary angiography (CTPA) protocols with low radiation dose, however, this has not been studied in the literature. The aim of this study was to investigate optimal CTPA protocols for detection of PE based on a 3D printed pulmonary model. METHODS: A patient-specific 3D printed pulmonary artery model was generated with thrombus placed in both main pulmonary arteries to represent PE. The model was scanned with 128-slice dual-source CT with slice thickness of 1 and 0.5 mm reconstruction interval. The tube voltage was selected to range from 70, 80, 100 to 120 kVp, and pitch value from 0.9 to 2.2 and 3.2. Quantitative assessment of image quality in terms of signal-to-noise ratio (SNR) was measured in the main pulmonary arteries and within the thrombus regions to determine the relationship between image quality and scanning protocols. Both two-dimensional (2D) and 3D virtual intravascular endoscopy (VIE) images were generated to demonstrate pulmonary artery and thrombus appearances. RESULTS: PE was successfully simulated in the 3D printed pulmonary artery model. There were no significant differences in SNR measured in the main pulmonary arteries with 100 and 120 kVp CTPA protocols (P>0.05), regardless of pitch value used. SNR was significantly lower in the high-pitch 3.2 protocols when compared to other protocols using 70 and 80 kVp (P<0.05). There were no significant differences in SNR measured within the thrombus among the 100 and 120 kVp protocols (P>0.05). For low dose 70 and 80 kVp protocols, SNR was significantly lower in the high-pitch of 3.2 protocols than that in other protocols with different pitch values (P<0.01). 2D images showed the pulmonary arteries and thrombus clearly, while 3D VIE demonstrated intraluminal appearances of pulmonary wall and thrombus in all protocols, except for the 70 kVp and pitch 3.2 protocol, with visualization of thrombus and pulmonary artery wall affected by artifact associated with high image noise. Radiation dose was reduced by up to 80% when lowering kVp from 120 to 100 and 80 kVp with use of 3.2 high-pitch protocol, without significantly affecting image quality. CONCLUSIONS: Low-dose CT pulmonary angiography can be achieved with use of low kVp (80 and 100) and high-pitch protocol with significant reduction in radiation dose while maintaining diagnostic images of PE. Use of high pitch, 3.2 in 70 kVp protocol should be avoided due to high image noise and poorer quality.

Patient-specific 3D printed pulmonary artery model with simulation of peripheral pulmonary embolism for developing optimal computed tomography pulmonary angiography protocols.

BACKGROUND: Computed tomography pulmonary angiography (CTPA) is the preferred imaging modality for diagnosis of patients with suspected pulmonary embolism (PE). Radiation dose associated with CTPA has been significantly reduced due to the use of dose-reduction strategies, however, investigation of low-dose CTPA with use of different kVp and pitch values has not been systematically studied. The aim of this study was to utilize a 3D printed pulmonary model with simulation of small thrombus in the pulmonary arteries for development of optimal CTPA protocols. METHODS: Animal blood clots were inserted into the pulmonary arteries to simulate peripheral embolism based on a realistic 3D printed pulmonary artery model. The 3D printed model was scanned with 192-slice 3rd generation dual-source CT with 1 mm slice thickness and 0.5 mm reconstruction interval. All images were reconstructed with advanced modelled iterative reconstruction (IR) at a strength level of 3. CTPA scanning parameters were as follows: 70, 80, 100 and 120 kVp, 0.9, 2.2 and 3.2 pitch values. Quantitative assessment of image quality was determined by measuring signal-to-noise ratio (SNR) in both main pulmonary arteries, while qualitative analysis of images was scored by two experienced radiologists (score of 1 indicates poor visualization of thrombus with no confidence, and score of 5 excellent visualization of thrombus with high confidence) to determine the image quality in relation to different scanning protocols for detection of thrombus in the pulmonary arteries. RESULTS: No significant differences were found in SNR measurements among all CTPA protocols (P>0.05), regardless of kVp or pitch values used, although SNR was higher with 120 kVp and 0.9 and 2.2 pitch protocols than that in other protocols. The thrombi were detected in all images, with 70 kVp and 3.2 pitch protocol scored the lowest with a score of 3 by two observers, and images with other protocols were scored 4 or 5. Lowering kVp from 120 to 70 with use of high-pitch 2.2 or 3.2 protocol resulted in up to 80% dose reduction without significantly affecting image quality. CONCLUSIONS: Low-dose CT pulmonary angiography protocols comprising 70 kVp and high pitch 2.2 or 3.2 allow for detection of peripheral PE with significant reduction in radiation dose while images are still considered diagnostic.

A Systematic Review of Double Low-dose CT Pulmonary Angiography in Pulmonary Embolism.

BACKGROUND: The aim of this study is to perform a systematic review of the feasibility and clinical application of double low-dose CT pulmonary angiography (CTPA) in the diagnosis of patients with suspected pulmonary embolism. DISCUSSION: A total of 13 studies were found to meet selection criteria reporting both low radiation dose (70 or 80 kVp versus 100 or 120 kVp) and low contrast medium dose CTPA protocols. Lowdose CTPA resulted in radiation dose reduction from 29.6% to 87.5% in 12 studies (range: 0.4 to 23.5 mSv), while in one study, radiation dose was increased in the dual-energy CT group when compared to the standard 120 kVp group. CTPA with use of low contrast medium volume (range: 20 to 75 ml) was compared to standard CTPA (range: 50 to 101 ml) in 12 studies with reduction between 25 and 67%, while in the remaining study, low iodine concentration was used with 23% dose reduction achieved. Quantitative assessment of image quality (in terms of signal-to-noise ratio and contrast-to-noise ratio) showed that low-dose CTPA was associated with higher, lower and no change in image quality in 3, 3 and 6 studies, respectively when compared to the standard CTPA protocol. The subjective assessment indicated similar image quality in 11 studies between low-dose and standard CTPA groups, and improved image quality in 1 study with low-dose CTPA. CONCLUSION: This review shows that double low-dose CTPA is feasible in the diagnosis of pulmonary embolism with significant reductions in both radiation and contrast medium doses, without compromising diagnostic image quality.