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In view of their superior soft tissue contrast compared to computed tomography, magnetic resonance images are commonly involved in stereotactic radiosurgery/radiotherapy applications for target delineation purposes. It is known, however, that magnetic resonance images are geometrically distorted, thus deteriorating dose delivery accuracy. The present work focuses on the assessment of geometric distortion inherent in magnetic resonance images used in stereotactic radiosurgery/radiotherapy treatment planning and attempts to quantitively evaluate the consequent impact on dose delivery. The geometric distortions for 3 clinical magnetic resonance protocols (at both 1.5 and 3.0 T) used for stereotactic radiosurgery/radiotherapy treatment planning were evaluated using a recently proposed phantom and methodology. Areas of increased distortion were identified at the edges of the imaged volume which was comparable to a brain scan. Although mean absolute distortion did not exceed 0.5 mm on any spatial axis, maximum detected control point disposition reached 2 mm. In an effort to establish what could be considered as acceptable geometric uncertainty, highly conformal plans were utilized to irradiate targets of different diameters (5-50 mm). The targets were mispositioned by 0.5 up to 3 mm, and dose–volume histograms and plan quality indices clinically used for plan evaluation and acceptance were derived and used to investigate the effect of geometrical uncertainty (distortion) on dose delivery accuracy and plan quality. The latter was found to be strongly dependent on target size. For targets less than 20 mm in diameter, a spatial disposition of the order of 1 mm could significantly affect (>5%) plan acceptance/quality indices. For targets with diameter greater than 2 cm, the corresponding disposition was found greater than 1.5 mm. Overall results of this work suggest that efficacy of stereotactic radiosurgery/radiotherapy applications could be compromised in case of very small targets lying distant from the scanner’s isocenter (eg, the periphery of the brain).

PURPOSE:Asthma control test (ACT) has been devised to assess the degree of asthma control in out-patients setting. The aim of this study is to validate the Arabic version of ACT.MATERIALS AND METHODS:Patients completed the Arabic version of ACT during regular visit to one of two asthma specialists. Spirometry was obtained. The asthma specialist rated asthma control using a 5-point scale and indicated modification in management as step up, same or step down of asthma treatment.RESULTS:40 patients completed the study, the mean age was 32.6 + 14.0 years, mean FEV1 was 2.7 + 1.0 L (89.2% + 23.6% of predicted). The mean ACT score was 15.9 + 5.8; mean of specialist asthma control rating was 3.4 + 1.0. The internal consistency reliability of the 5-item ACT survey was alpha = 0.92. The correlation was moderate between ACT and specialists rating (r = 0.482, P = 0.002) and between ACT and treatment modification (r = −0.350, P = 0.027). The correlation between FEV1 and ACT was low (r = 0.185, P = 0.259). ACT distinguished between patients with different specialist rating (F = 3.37, P = 0.02) and the need to change therapy (F = 3.62, P = 0.037). The areas under the curve (ROC) for ACT, FEV1, and ACT and FEV1 as independent variables were 0.720, 0.721, and 0.766 respectively. All results were comparable to the initial work for development of ACT.CONCLUSION:The Arabic version of the ACT is a valid tool to assess asthma control. ACT correlates better with asthma specialist rating of asthma control than with FEV1.

AimTo assess parental perceptions and beliefs about asthma in children.MethodsWe invited 6000 children aged 3 to 15 years from different schools in Lebanon to participate in the study from September 2007 to May 2008. In the first phase, in order to determine the prevalence of asthma in children, parents of all participating children filled out a small questionnaire. In the second phase, only parents of children with asthma filled out a detailed questionnaire about their perceptions of asthma.ResultsPhase I included parents of 4051 children, 574 (14%) of whom had asthma and were recruited to phase II. Out of these, 389 parents entered the final data analysis. Around 54% of parents believed that asthma was hereditary and 7% believed it was contagious. When asked about triggering factors, 51% stated virus infection, 75% dust, and 17% food. Sixty percent of children with asthma lived with someone who smoked. Sixty-seven percent of parents believed that herbs had a role in asthma treatment and only 49% received asthma education. There was a significant difference in education level (P = 0.01) between the parents who denied the label of asthma (79%) and those who accepted it (21%). Sixty-seven percent of parents preferred oral over inhaler treatment, 48% believed inhalers were addictive, 56% worried about inhalers’ side effects, and 76% worried about using inhaled corticosteroids. Significantly more parents from rural (53%) than from urban areas (38%) believed that inhalers were addictive (P = 0.004).ConclusionParents of children with asthma had considerable misperceptions about the use of inhalers and the safety of inhaled corticosteroids. To improve asthma care in children, it is necessary to provide adequate education to parents.

Chronic inflammatory airway diseases, including asthma, chronic rhinosinusitis, eosinophilic COPD and allergic rhinitis are a global health concern. Despite the coexistence of these diseases and their common pathophysiology, they are often managed independently, resulting in poor asthma control, continued symptoms and poor quality of life. Understanding disease pathophysiology is important for best treatment practice, reduced disease burden and improved patient outcomes.The pathophysiology of type 2 inflammation is driven by both the innate immune system triggered by pollutants, viral or fungal infections involving type 2 innate lymphoid cells (ILC2) and the adaptive immune system, triggered by contact with an allergen involving type 2 T-helper (Th2) cells. Both ILC2 and Th2 cells produce the type-2 cytokines (interleukin (IL)-4, IL-5 and IL-13), each with several roles in the inflammation cascade. IL-4 and IL-13 cause B-cell class switching and IgE production, release of pro-inflammatory mediators, barrier disruption and tissue remodelling. In addition, IL-13 causes goblet-cell hyperplasia and mucus production. All three interleukins are involved in trafficking eosinophils to tissues, producing clinical symptoms characteristic of chronic inflammatory airway diseases.Asthma is a heterogenous disease; therefore, identification of biomarkers and early targeted treatment is critical for patients inadequately managed by inhaled corticosteroids and long-acting β-agonists alone. The Global Initiative for Asthma guidelines recommend add-on biological (anti IgE, IL-5/5R, IL-4R) treatments for those not responding to standard of care. Targeted therapies, including omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab and tezepelumab, were developed on current understanding of the pathophysiology of type 2 inflammation. These therapies offer hope for improved management of type 2 inflammatory airway diseases.

The Saudi Thoracic Society (STS) launched the Saudi Initiative for Chronic Airway Diseases (SICAD) to develop a guideline for the diagnosis and management of chronic obstructive pulmonary disease (COPD). This guideline is primarily aimed for internists and general practitioners. Though there is scanty epidemiological data related to COPD, the SICAD panel believes that COPD prevalence is increasing in Saudi Arabia due to increasing prevalence of tobacco smoking among men and women. To overcome the issue of underutilization of spirometry for diagnosing COPD, handheld spirometry is recommended to screen individuals at risk for COPD. A unique feature about this guideline is the simplified practical approach to classify COPD into three classes based on the symptoms as per COPD Assessment Test (CAT) and the risk of exacerbations and hospitalization. Those patients with low risk of exacerbation (<2 in the past year) can be classified as either Class I when they have less symptoms (CAT < 10) or Class II when they have more symptoms (CAT ≥ 10). High-risk COPD patients, as manifested with ≥2 exacerbation or hospitalization in the past year irrespective of the baseline symptoms, are classified as Class III. Class I and II patients require bronchodilators for symptom relief, while Class III patients are recommended to use medications that reduce the risks of exacerbations. The guideline recommends screening for co-morbidities and suggests a comprehensive management approach including pulmonary rehabilitation for those with a CAT score ≥10. The article also discusses the diagnosis and management of acute exacerbations in COPD.

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