Simultaneous Mapping of T1 and T2 Using Cardiac Magnetic Resonance Fingerprinting in a Cohort of Healthy Subjects at 1.5T.

BACKGROUND: Cardiac MR fingerprinting (cMRF) is a novel technique for simultaneous T1 and T2 mapping. PURPOSE: To compare T1 /T2 measurements, repeatability, and map quality between cMRF and standard mapping techniques in healthy subjects. STUDY TYPE: Prospective. POPULATION: In all, 58 subjects (ages 18-60). FIELD STRENGTH/SEQUENCE: cMRF, modified Look-Locker inversion recovery (MOLLI), and T2 -prepared balanced steady-state free precession (bSSFP) at 1.5T. ASSESSMENT: T1 /T2 values were measured in 16 myocardial segments at apical, medial, and basal slice positions. Test-retest and intrareader repeatability were assessed for the medial slice. cMRF and conventional mapping sequences were compared using ordinal and two alternative forced choice (2AFC) ratings. STATISTICAL TESTS: Paired t-tests, Bland-Altman analyses, intraclass correlation coefficient (ICC), linear regression, one-way analysis of variance (ANOVA), and binomial tests. RESULTS: Average T1 measurements were: basal 1007.4±96.5 msec (cMRF), 990.0±45.3 msec (MOLLI); medial 995.0±101.7 msec (cMRF), 995.6±59.7 msec (MOLLI); apical 1006.6±111.2 msec (cMRF); and 981.6±87.6 msec (MOLLI). Average T2 measurements were: basal 40.9±7.0 msec (cMRF), 46.1±3.5 msec (bSSFP); medial 41.0±6.4 msec (cMRF), 47.4±4.1 msec (bSSFP); apical 43.5±6.7 msec (cMRF), 48.0±4.0 msec (bSSFP). A statistically significant bias (cMRF T1 larger than MOLLI T1 ) was observed in basal (17.4 msec) and apical (25.0 msec) slices. For T2 , a statistically significant bias (cMRF lower than bSSFP) was observed for basal (-5.2 msec), medial (-6.3 msec), and apical (-4.5 msec) slices. Precision was lower for cMRF-the average of the standard deviation measured within each slice was 102 msec for cMRF vs. 61 msec for MOLLI T1 , and 6.4 msec for cMRF vs. 4.0 msec for bSSFP T2 . cMRF and conventional techniques had similar test-retest repeatability as quantified by ICC (0.87 cMRF vs. 0.84 MOLLI for T1 ; 0.85 cMRF vs. 0.85 bSSFP for T2 ). In the ordinal image quality comparison, cMRF maps scored higher than conventional sequences for both T1 (all five features) and T2 (four features). DATA CONCLUSION: This work reports on myocardial T1 /T2 measurements in healthy subjects using cMRF and standard mapping sequences. cMRF had slightly lower precision, similar test-retest and intrareader repeatability, and higher scores for map quality. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1 J. Magn. Reson. Imaging 2020;52:1044-1052.

Evaluation of dyspnea of unknown etiology in HIV patients with cardiopulmonary exercise testing and cardiovascular magnetic resonance imaging.

AIM: Human Immunodeficiency Virus (HIV) patients commonly experience dyspnea for which an immediate cause may not be always apparent. In this prospective cohort study of HIV patients with exercise limitation, we use cardiopulmonary exercise testing (CPET) coupled with exercise cardiovascular magnetic resonance (CMR) to elucidate etiologies of dyspnea. METHODS AND RESULTS: Thirty-four HIV patients on antiretroviral therapy with dyspnea and exercise limitation (49.7 years, 65% male, mean absolute CD4 count 700) underwent comprehensive evaluation with combined rest and maximal exercise treadmill CMR and CPET. The overall mean oxygen consumption (VO2) peak was reduced at 23.2 ± 6.9 ml/kg/min with 20 patients (58.8% of overall cohort) achieving a respiratory exchange ratio > 1. The ventilatory efficiency (VE)/VCO2 slope was elevated at 36 ± 7.92, while ventilatory reserve (VE: maximal voluntary ventilation (MVV)) was within normal limits. The mean absolute right ventricular (RV) and left ventricular (LV) contractile reserves were preserved at 9.0% ± 11.2 and 9.4% ± 9.4, respectively. The average resting and post-exercise mean average pulmonary artery velocities were 12.2 ± 3.9 cm/s and 18.9 ± 8.3 respectively, which suggested lack of exercise induced pulmonary artery hypertension (PAH). LV but not RV delayed enhancement were identified in five patients. Correlation analysis found no relationship between peak VO2 measures of contractile RV or LV reserve, but LV and RV stroke volume correlated with PET CO2 (p = 0.02, p = 0.03). CONCLUSION: Well treated patients with HIV appear to have conserved RV and LV function, contractile reserve and no evidence of exercise induced PAH. However, we found evidence of impaired ventilation suggesting a non-cardiopulmonary etiology for dyspnea.

Multidisciplinary approach to paediatric aerodigestive disorders: A single-centre longitudinal observational study.

AIM: Aerodigestive clinics (ADCs) are multidisciplinary programmes for the care of children with complex congenital or acquired conditions affecting breathing, swallowing and growth. Our objective was to describe the demographic, clinical, etiological and investigational profile of children attending the inaugural ADC at a tertiary paediatric centre in Queensland. METHODS: Children referred to the ADC at Queensland Children's Hospital from August 2018 to December 2019 were included. Data on clinical, growth and lung function parameters, bronchoscopy and upper gastrointestinal endoscopy findings, thoracic imaging and comorbidities were retrospectively analysed. RESULTS: Fifty-six children (median (range) age 4 years (3 months-15 years); 18 female) attended the ADC during this 17-month period. Forty-six (82%) children had previous oesophageal atresia with tracheo-oesophageal fistula; 43 of these were type C. Previous isolated oesophageal atresia, congenital diaphragmatic hernia and congenital pulmonary malformation were the underlying disorder in three (5%) children each, with one child having a repaired laryngeal cleft. Vertebral Anal Tracheo Esophageal Renal Limb anomalies (VACTERL)/Vertebral Anal Tracheo Esophageal renal anomalies (VATER) association was seen in 21 (38%) children. Growth was adequate (median weight and body mass index z-score -0.63 and -0.48, respectively). Thirty-four (61%) children reported ongoing wet cough, with 12 (21%) requiring previous hospital admission for lower respiratory tract infection. Fourteen (25%) had bronchiectasis on computed tomography chest and 33 (59%) had clinical tracheomalacia, apparent on bronchoscopic examination in 21 patients. Dysphagia was reported in 15 (27%) children, 11 (20%) were gastrostomy feed-dependent and 5 (9%) had biopsy-proven eosinophilic oesophagitis. CONCLUSION: High proportion of children attending the ADC have ongoing respiratory symptoms resulting in chronic pulmonary suppuration and bronchiectasis. Potential benefits of this model of care need to be studied prospectively to better understand the outcomes.

Unenhanced Velocity-Selective MR Angiography (VS-MRA): Initial Clinical Evaluation in Patients With Peripheral Artery Disease.

BACKGROUND: Safe and accurate imaging of the peripheral arterial system is important for diagnosis and treatment planning of patients with peripheral artery disease (PAD). PURPOSE: To evaluate image quality and diagnostic performance of unenhanced magnetic resonance angiography (MRA) based on velocity-selective (VS) magnetization preparation (termed VS-MRA). STUDY TYPE: Prospective. POPULATION: Thirty-one symptomatic PAD patients underwent VS-MRA. Twenty-four of them underwent clinical digital subtraction angiography (DSA) examination, 18.8 ± 5.2 days after the MR scans. FIELD STRENGTH/SEQUENCE: 1.5T MRI that included VS-MRA (homemade research sequence) and phase-contrast flow imaging (clinical sequence). ASSESSMENT: Image quality (0: nondiagnostic, 3: excellent) and stenosis severity (0: normal, 3: occlusion) of VS-MRA images were assessed independently by three reviewers. Arterial signal-to-noise-ratio (SNR) and artery-to-muscle contrast-to-noise ratio (CNR) were calculated. STATISTICAL TESTS: The sensitivity and specificity of VS-MRA were calculated for the detection of significant stenosis (>50%) with DSA as the reference standard. Interobserver agreement among the three reviewers was evaluated by using Cohen κ-statistics. RESULTS: The image quality score of VS-MRA was 2.7 ± 0.5 for Reader 1, 2.8 ± 0.5 for Reader 2, and 2.8 ± 0.4 for Reader 3; SNR and CNR were 37.8 ± 12.5 and 30.5 ± 11.8, respectively. Segment-based analysis revealed that VS-MRA had sensitivities of 85.3%, 74.5%, and 78.4%, respectively, for the three reviewers, and specificities of 93.5%, 96.8%, and 95.2%. The interobserver agreement for the stenosis grading was good, as demonstrated by Cohen κ values of 0.76 (Reader 1 vs. Reader 2), 0.82 (Reader 1 vs. Reader 3), and 0.79 (Reader 2 vs. Reader 3). DATA CONCLUSION: Unenhanced VS-MRA allows clear depiction of the peripheral arteries and accurate stenosis grading, as evidenced by high image quality scores and strong agreement with DSA. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:744-751.

Impact of residual coronary atherosclerosis on transfemoral transcatheter aortic valve replacement.

OBJECTIVES: This study reports on the clinical effects of complete vs incompletely revascularized coronary artery disease on transcatheter aortic valve replacement (TAVR). BACKGROUND: There is a high prevalence of active coronary artery disease (CAD) in patients undergoing TAVR but preemptive revascularization remains controversial. METHODS: Patients were categorized into three cohorts: complete revascularization (CR), incomplete revascularization of a major epicardial artery (IR Major), and incomplete revascularization of a minor epicardial artery only (IR Minor). When feasible, SYNTAX scoring was performed for exploratory analysis. Analyses were performed using Cox proportional hazard models and Kaplan-Meier method. RESULTS: A total of 323 patients with active CAD were included. Adjusted outcomes showed that patients with IR Major had increased incidence of acute myocardial infarction (AMI) or revascularization compared with those in the CR cohort (HR 3.72, P = 0.048). No difference was noted in all-cause mortality or all-cause readmission rates. Exploratory secondary analysis with residual SYNTAX scores showed a significant interaction between disease burden and AMI/revascularization, as well as all-cause readmission. All-cause mortality remained unaffected based on residual SYNTAX scores. CONCLUSIONS: This is a retrospective single-center study reporting on pre-TAVR revascularization outcomes in patients with active CAD. In this analysis, we found that patients undergoing TAVR benefited from achieving complete revascularization to abate future incidence of AMI/revascularization. Despite this finding, all-cause mortality remained unaffected. Future efforts should focus on the role of functional assessment of the coronaries, as well as the long-term effects of complete revascularization in a larger patient cohort.

Comparison of fieldworker interview and a pictorial diary method for recording morbidity of infants in semi-urban slums.

BACKGROUND: Cohort studies conducted in low-income countries generally use trained fieldworkers for collecting data on home visits. In industrialised countries, researchers use less resource intensive methods, such as self-administered structured questionnaires or symptom diaries. This study compared and assessed the reliability of the data on diarrhoea, fever and cough/cold in children as obtained by a pictorial diary maintained by the mother and collected separately by a fieldworker. METHODS: A sample of 205 children was randomly selected from an ongoing birth cohort study. Pictorial diaries were distributed weekly to mothers of study children who were asked to maintain a record of morbidity for four weeks. We compared the reliability and completeness of the data on diarrhoea, fever and cough/cold obtained by the two methods. RESULTS: Of 205 participants, 186 (91%) ever made a record in the diary and 62 (30%) mothers maintained the diary for all 28 days. The prevalence-adjusted bias-adjusted kappa statistics for diarrhoea, fever, cough/cold and for a healthy child were 92%, 79%, 35% and 35% respectively. CONCLUSION: Diary recording was incomplete in the majority of households. When recorded, the morbidity data by the pictorial diary method for acute illnesses were reliable. Strategies are needed to address behavioural factors affecting maternal recording such that field studies can obtain accurate morbidity measurements with limited resources.

Establishment of the MAL-ED birth cohort study site in Vellore, Southern India.

The Indian Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) site is in Vellore, Tamil Nadu, in south India and is coordinated by the Christian Medical College, Vellore, which has many years of experience in establishing and following cohorts. India is a diverse country, and no single area can be representative with regard to many health and socioeconomic indicators. The site in Vellore is an urban semiorganized settlement or slum. In the study site, the average family size is 5.7, adults who are gainfully employed are mostly unskilled laborers, and 51% of the population uses the field as their toilet facility. Previous studies from Vellore slums have reported stunting in well over a third of children, comparable to national estimates. The infant mortality rate is 38 per 1000 live births, with deaths due mainly to perinatal and infectious causes. Rigorous staff training, monitoring, supervision and refinement of tools have been essential to maintaining the quality of the significantly large quantity of data collected. Establishing a field clinic within the site has minimized inconvenience to participants and researchers and enabled better rapport with the community and better follow-up. These factors contribute to the wealth of information that will be generated from the MAL-ED multisite cohort, which will improve our understanding of enteric infections and its interactions with malnutrition and development of young children.

Endovascular treatment of infrainguinal chronic total occlusions using the TruePath device: features, handling, and 6-month outcomes.

PURPOSE: To report experience with a recently approved peripheral chronic total occlusion (CTO) crossing device in the superficial femoral (SFA), popliteal, and below-the-knee (BTK) arteries. METHODS: Thirteen patients (all men; mean age 68.6±7.9 years) from the XLPAD registry (ClinicalTrials.gov identifier NCT01904851) were treated between April 2012 and August 2013 with the TruePath device after an unsuccessful guidewire crossing attempt. More than half of the patients had diabetes mellitus. Most lesions were TASC classification type C (n=5) or D (n=6), with mean lesion length 169.8±83.3 mm; 12 lesions were de novo and severely calcified. Procedure success was defined as successful revascularization of the CTO. Technical success was placement of a guidewire beyond the distal CTO cap into the true lumen without the need for a re-entry device. RESULTS: All CTOs were successfully crossed using the TruePath, but 3 subintimal recanalizations required the use of a re-entry device (77% technical success). Eight lesions were stented, while the remaining were treated with balloon angioplasty and/or atherectomy. Average fluoroscopy time was 41.1±18.3 minutes, during which a mean 200.0±46.2 mL of iodinated contrast were used (radiation dose area product 211.2±202.6 Gy*cm(2)). There were no periprocedural complications. Significant improvement was seen in the 6-month ankle-brachial index (p=0.018) and Rutherford class (p=0.019). The 6-month clinically indicated target vessel revascularization rate was 8%. CONCLUSION: TruePath facilitated successful crossing of infrainguinal CTOs following an unsuccessful guidewire recanalization, with significant improvement in symptoms and no complications.

Blunt microdissection for endovascular treatment of infrainguinal chronic total occlusions.

PURPOSE: To present a systematic safety evaluation of the CrossBoss blunt microdissection catheter for crossing peripheral chronic total occlusions (CTOs). METHODS: Between July 2010 and July 2011, 15 patients (all men; mean age 60.7±9.1 years) underwent endovascular treatment of 17 infrainguinal CTOs that were resistant to guidewire passage, so the blunt microdissection catheter was employed to recanalize the artery. Fourteen lesions were de novo and 3 were in-stent restenoses. Sixteen lesions were in the superficial femoral artery; 8 of 17 CTOs were TASC II type D. Extensive calcification was present in 12 lesions. Mean lesion length was 182.9±66.2 mm (range 57-296). RESULTS: Procedural success was 100% and successful crossing without the use of a re-entry device (technical success) was achieved in 15 cases. Twelve lesions were stented. Average fluoroscopy time was 36.5±21.2 minutes (143.8±76.9 Gy*cm (2) radiaton dose area product), during which a mean 172.1±62.2 mL of iodinated contrast were used. Two patients had access site hematomas that were treated conservatively, and there was no perforation, distal embolization, amputation, or need for urgent revascularization. During the mean follow-up of 11.4±0.1 months, 1 patient died, and none required an amputation or surgical revascularization. There was a significant improvement in ankle-brachial index (0.6±0.1 to 0.8±0.2, p=0.001) and symptoms as assessed by Rutherford class at 1 year. Four of 17 limbs required secondary revascularization procedures within 1 year. CONCLUSION: The CrossBoss blunt microdissection catheter facilitated successful crossing of CTOs in patients with infrainguinal lesions following unsuccessful guidewire crossing, with an acceptably low rate of periprocedural complications and significant improvement in symptoms.

Role of Spirometry, Radiology, and Flexible Bronchoscopy in Assessing Chronic Cough in Children.

Chronic cough in children is a common and multifaceted symptom, often requiring a comprehensive approach for accurate diagnosis and effective management. This review explores the use of spirometry, radiology (chest X-rays and computed tomography (CT) scans), and flexible bronchoscopy in the assessment of chronic cough in children through current guidelines and studies. The strengths, clinical indications, and limitations of each modality are examined. Spirometry, radiology, and in some cases flexible bronchoscopy are integral to the assessment of chronic cough in children; however, a tailored approach, leveraging the strengths of each modality and guided by clinical indications, enhances diagnostic accuracy and therapeutic outcomes of pediatric chronic cough.

Clinical utility of elective paediatric flexible bronchoscopy and impact on the quality of life: protocol for a single-centre, single-blind, randomised controlled trial.

INTRODUCTION: Elective flexible bronchoscopy (FB) is now widely available and standard practice for a variety of indications in children with respiratory conditions. However, there are no randomised controlled trials (RCTs) that have examined its benefits (or otherwise).Our primary aim is to determine the impact of FB on the parent-proxy quality-of-life (QoL) scores. Our secondary aims are to determine if undertaking FB leads to (a) change in management and (b) improvement of other relevant patient-reported outcome measures (PROMs). We also quantified the benefits of elective FB (using 10-point Likert scale). We hypothesised that undertaking elective FB will contribute to accurate diagnosis and therefore appropriate treatment, which will in turn improve QoL and will be deemed to be beneficial from patient and doctor perspectives. METHODS AND ANALYSIS: Our parallel single-centre, single-blind RCT (commenced in May 2020) has a planned sample size of 114 children (aged <18 years) recruited from respiratory clinics at Queensland Children's Hospital, Brisbane, Australia. Children are randomised (1:1 concealed allocation) within two strata: age (≤2 vs >2 years) and indication for FB (chronic cough vs other indications) to either (a) early arm (intervention where FB undertaken within 2 weeks) or (b) delayed (control, FB undertaken at usual wait time). Our primary outcome is the difference between groups in their change in QoL at the T2 timepoint when the intervention group has had the FB and the control group has not. Our secondary outcomes are change in management, change in PROMs, adverse events and the Likert scales. ETHICS AND DISSEMINATION: The human research ethics committee of the Queensland Children's Hospital granted ethical clearance (HREC/20/QCHQ/62394). Our RCT is conducted in accordance with Good Clinical Practice and the Australian legislation. Results will be disseminated through conference presentations, teaching avenues, workshops, websites and publications. REGISTRATION: Australia New Zealand Clinical Trial Registry ACTRN12620000610932.

The utility of elective flexible bronchoscopy to improve quality of life and clinical outcomes for children: A systematic review.

INTRODUCTION: Elective flexible bronchoscopy (FB) is now widely available and standard practice for a variety of indications in children with respiratory conditions. However, there is limited evidence regarding the utility of elective FB in children. This systematic review (SRs) aimed to determine the utility of FB on its impact in clinical decision making and quality of life (QoL). METHODS: We searched Pubmed, Cochrane central register of controlled trials, Embase, World Health Organization Clinical Trials Registry Platform and Cochrane database of SRs from inception to April 20, 2023. We included SRs and randomized controlled trials (RCTs) that used parallel group design (comparing use of elective FB vs. no FB, or a wait-list approach [early FB vs. usual wait FB]) in children aged ≤ 18 years. Our protocol was prospectively registered and used Cochrane methodology for systemic reviews of interventions. RESULTS: Our search identified 859 articles; 102 duplicates were removed, and 753 articles were excluded by title and abstract. Four full text articles were reviewed and subsequently excluded, as none met the inclusion criteria outlined in our patient, intervention, comparator, outcome measures framework. CONCLUSIONS: There is a paucity of high-quality RCT evidence to support the routine use of elective FB in children with respiratory conditions. However, available retrospective and a single prospective study demonstrate the high utility of FB in the elective pediatric setting. REGISTRATION: PROSPERO CRD42021291305.

Flexible Bronchoscopy Diagnosis of Uncommon Congenital H-type Tracheoesophageal Fistula, Dual Fistulae, Bronchoesophageal Fistula, and Recurrence of Fistula in Children: A 20-year Experience.

BACKGROUND: Interventional pediatric flexible bronchoscopy has many advantages over radiologic investigations in diagnosing uncommon congenital H-type tracheoesophageal fistula (TEF), dual TEF, bronchoesophageal fistula (BEF) and fistula recurrence including higher rates of identification and anatomic localization with guide wire cannulation. We compare the diagnostic utility of flexible bronchoscopy to radiologic techniques for congenital aerodigestive fistula. METHODS: A single center retrospective review was completed of all cases of pediatric TEF and BEF diagnosed with flexible bronchoscopy between January 2000 and November 2020. RESULTS: Fistulae were diagnosed 21 times in 18 patients at a median age of 1.22 years (interquartile range: 0.50 to 2.99). The median time from diagnosis to repair was 17.5 days (interquartile range: 5.5 to 43). Symptoms commonly related to fistula were found in all patients. Uncommon fistulae included single H-type TEF (n=10, 47.6%), dual H-type TEF (n=2, 9.5%), dual proximal and distal TEF with esophageal atresia (n=5, 23.8%), TEF recurrence (n=2, 14.3%), BEF (n=1, 4.8%), and a BEF recurrence (n=1, 4.8%). Flexible bronchoscopy confirmed the diagnosis in all fistulae using a guide wire cannulation or methylene blue dye injection. A combined procedure with simultaneous bronchoscopy and esophagoscopy was used for 6 fistulae. The positive examination rate was 75% for bronchoscopy compared with 2.6% for contrast swallow studies and 28.6% for tube esophagograms. CONCLUSIONS: Flexible bronchoscopy should be considered as a first line investigation in uncommon aerodigestive fistulae. In the absence of a skilled bronchoscopist, the best radiologic investigation is a pull-back tube esophagogram but may still require endoscopic confirmation at the time of fistula repair.

Lung parenchymal calcifications in a child with cystic fibrosis.

We describe a 6-year-old girl with homozygous p.Phe508del cystic fibrosis with severe multi-lobar bronchiectasis and obstructive lung disease who was found to have prominent parenchymal calcifications in the right middle lobe on a computed tomography scan of the chest. Histopathology from the calcified area of lung biopsy showed fibrous tissue with chronic inflammation with CD3+ T-lymphocytes and macrophages with no granulomas. Dystrophic calcification was seen within this necrotic debris.

The 'knee' pattern in spirometry flow-volume curves in children: Does it relate to tracheomalacia?

BACKGROUND: There is little data on patterns of spirometry curves in children with tracheomalacia but convex inflection on flow-volume curves (identified as the 'knee') is thought to represent tracheomalacia. OBJECTIVES: To determine (a) the prevalence of tracheomalacia in children with the 'knee' pattern on spirometry, and (b) whether spirometry parameters and visual characteristics of the 'knee' can identify presence/absence or severity of tracheomalacia. PATIENTS/METHODS: We reviewed the spirometry undertaken at Queensland Children's Hospital between 2016 and 2019 and retrieved spirometry with the 'knee' pattern in the flow-volume curves. Flexible bronchoscopy videos of these children were reviewed for tracheomalacia diagnosis and severity in a blinded manner. We also evaluated several 'knee' characteristics (onset of inflection, angle of inflection, a scoop before plateau, plateau progression), spirometry parameters and tracheomalacia severity. RESULTS: Of the 78 children with the 'knee', 51 (65.4%) had tracheomalacia. Spirometry values were significantly lower in those with tracheomalacia, compared to those without (predicted FEV1 = 86.1% vs 99.9%, FVC = 95.1% vs 104%, FEF25-75% = 68.6% vs 89.6%, all p < 0.02). A scoop before plateau was significantly associated with tracheomalacia (66.7% vs 40.7%, p = 0.03). There was no significant difference in spirometry parameters or the 'knee' characteristics between children with mild versus moderate-to-severe tracheomalacia. CONCLUSION: Most but not all children with the 'knee' pattern have flexible bronchoscopy-defined tracheomalacia. Those with tracheomalacia had lower spirometry values and the presence of a scoop before plateau was the most characteristic feature. A prospective longitudinal study is required to determine the diagnostic value of spirometry flow-volume curve characteristics in children.

Pulmonary function of children with tracheomalacia and associated clinical factors.

OBJECTIVES: Spirometry is easily accessible yet there is limited data in children with tracheomalacia. Availability of such data may inform clinical practice. We aimed to describe spirometry indices of children with tracheomalacia, including Empey index and flow-volume curve pattern, and determine whether these indices relate with bronchoscopic features. METHODS: From the database of children with tracheomalacia diagnosed during 2016-2019, we reviewed their flexible bronchoscopy and spirometry data in a blinded manner. We specially evaluated several spirometry indices and tracheomalacia features (cross-sectional lumen reduction, malacic length, and presence of bronchomalacia) and determined their association using multivariable regression. RESULTS: Of 53 children with tracheomalacia, the mean (SD) peak expiratory flow (PEF) was below the normal range [68.9 percent of predicted value (23.08)]. However, all other spirometry parameters were within normal range [Z-score forced expired volume in 1 s (FEV1 ) = -1.18 (1.39), forced vital capacity (FVC) = -0.61 (1.46), forced expiratory flow between 25% and 75% of vital capacity​​​​​​ (FEF25%-75% ) = -1.43 (1.10), FEV1 /FVC = -1.04 (1.08)], Empey Index = 8.21 (1.59). The most common flow-volume curve pattern was the "knee" pattern (n = 39, 73.6%). Multivariable linear regression identified the presence of bronchomalacia was significantly associated with lower flows: FEV1 [coefficient (95% CI) -0.78 (-1.54, -0.02)], FEF25%-75% [-0.61 (-1.22, 0)], and PEF [-12.69 (-21.13, -4.25)], all p ≤ 0.05. Other bronchoscopic-defined tracheomalacia features examined (cross-sectional lumen reduction, malacic length) were not significantly associated with spirometry indices. CONCLUSION: The "knee" pattern in spirometry flow-volume curve is common in children with tracheomalacia but other indices, including Empey index, cannot be used to characterize tracheomalacia. Spirometry indices were not significantly associated with bronchoscopic tracheomalacia features but children with tracheobronchomalacia have significantly lower flow than those with tracheomalacia alone.

Association of childhood tracheomalacia with bronchiectasis: a case-control study.

OBJECTIVE: Children with tracheomalacia can develop chronic lower airway infection and neutrophilic inflammation. It is plausible children with tracheomalacia are at increased risk of developing bronchiectasis. We hypothesised that compared with controls, tracheomalacia in children is associated with bronchiectasis. DESIGN: Single-centre, case-control study. SETTING AND PATIENTS: 45 children with chest high-resolution CT (c-HRCT) confirmed bronchiectasis (cases) and enrolled in the Australian Bronchiectasis Registry were selected randomly from Queensland, and 90 unmatched children without chronic respiratory symptoms or radiographic evidence of bronchiectasis (disease controls). Cases and controls had flexible bronchoscopy performed for clinical reasons within 4 weeks of their c-HRCT. INTERVENTIONS: The bronchoscopy videos were reviewed in a blinded manner for: (a) any tracheomalacia (any shape deformity of the trachea at end-expiration) and (b) tracheomalacia defined by the European Respiratory Society (ERS) statement (>50% expiratory reduction in the cross-sectional luminal area). MAIN OUTCOME MEASURES AND RESULTS: Cases were younger (median age=2.6 years, IQR 1.5-4.1) than controls (7.8 years, IQR 3.4-12.8), but well-balanced for sex (56% and 52% male, respectively). Using multivariable analysis (adjusted for age), the presence of any tracheomalacia was significantly associated with bronchiectasis (adjusted OR (ORadj)=13.2, 95% CI 3.2 to 55), while that for ERS-defined tracheomalacia further increased this risk (ORadj=24.4, 95% CI 3.4 to infinity). CONCLUSION: Bronchoscopic-defined tracheomalacia is associated with childhood bronchiectasis. While causality cannot be inferred, children with tracheomalacia should be monitored for chronic (>4 weeks) wet cough, the most common symptom of bronchiectasis, which if present should be treated and then investigated if the cough persists or is recurrent.

Smartphone videos to predict the severity of obstructive sleep apnoea.

OBJECTIVE: Diagnosis of obstructive sleep apnoea (OSA) is made on overnight polysomnography (PSG). Given the widespread availability of smartphone video technology, we aimed to develop and test a standardised scoring system for smartphone videos and compare these scores to PSG results. METHODS: Children aged 1-16 years undergoing PSG for suspected OSA were included. Parents were asked to take 1-2 min videos of the breathing they were concerned about. Videos were scored using a newly developed and tested tool on five components: inspiratory obstructive noises (1-4), presence of obstructive events (0-1), increased work of breathing (0-1), mouth breathing (0-1) and neck extension (0-1). Video scores and the Obstructive Apnoea Hypopnoea Index (OAHI) were compared using Spearman correlation. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for different cut-off scores to achieve the best results. RESULTS: Videos from 43 children (28 men (65.1%), median age 5.7 years (range 2.6-14.0 years), median OAHI 3.8/hour (range 0-82 events/hour) were included. Nine children (20.9%) had a video score of <3, all of whom had an OAHI of ≤5 events/hour. For a video score of ≥3, sensitivity was 100%; specificity was 36%; positive predictive value was 53%; and negative predictive value 100% for moderate to severe OSA (OAHI>5 events/hour) . CONCLUSION: We have developed and validated a simple clinical tool (the Monash Obstructive Sleep Apnoea Video Score) to quantify abnormalities in breathing seen on short video recordings made on a smartphone. A low score rules out moderate-severe OSA and may be valuable in the triage of children with symptoms of OSA.

Verbal feedback enhances motor learning during post-stroke gait retraining.

BACKGROUND: Fast treadmill walking combined with functional electrical stimulation to ankle muscles (FastFES) is a well-studied gait intervention that improves post-stroke walking function. Although individualized verbal feedback is commonly incorporated during clinical gait training, and a variable practice structure is posited to enhance learning, the influence of these two factors on motor learning during locomotor interventions such as FastFES is poorly understood. OBJECTIVES: To determine if the addition of individualized verbal feedback or variable practice to a FastFES training session enhances motor learning of targeted gait patterns. METHODS: Nine individuals with post-stroke hemiparesis completed a crossover study comprising exposure to 3 dose-matched types of gait training: (1) FastFES (FF), comprising five 6-minute bouts of training with intermittent FES, (2) FF with addition of individualized verbal instructions and faded feedback delivered by a physical therapist (FF+PT), (3) FF with variable gait speed and FES timing (FF+Var). Gait biomechanics data were collected before (Pre), immediately after (Post), and 24-h following (Retention) each training type. Within-session and retention change scores of 3 targeted gait variables were calculated to assess locomotor learning. RESULTS: FF+PT resulted in larger improvements within-session and at retention in trailing limb angle, and a trend for larger improvements in paretic pushoff compared to FF. FF+Var failed to show greater learning of biomechanical variables compared to FF. CONCLUSIONS: Addition of individualized verbal feedback (FF+PT) to a single session of gait training may enhance within- and across-session learning of targeted gait variables in people post-stroke, and merits more investigation.

Development and validation of a bronchoscopically defined bronchitis scoring tool in children.

INTRODUCTION/AIM: A validated tool for scoring bronchitis during flexible bronchoscopy (FB) is potentially useful for clinical practice and research. We aimed to develop a bronchoscopically defined bronchitis scoring system in children (BScore) based on our pilot study. METHODS: Children undergoing FB were prospectively enrolled. Their FB was digitally recorded and assessed (two clinicians blinded to each other and clinical history) for six features: secretion amount (six-point scale), secretion color (BronkoTest, 0-8), mucosal oedema (0-3), ridging (0-3), erythema (0-3), and pallor (0-3) based on pre-determined criteria. We correlated (Spearman's rho) each feature with bronchoalveolar lavage (BAL) neutrophil percentage (neutrophil%). BScore was then derived using models with combinations of the six features that best related to airway BAL neutrophil%. The various models of BScore were plotted against BAL neutrophil% using receiver operating characteristic (ROC) curves. RESULTS: We analyzed 142 out of 150 children enrolled. Eight children were excluded for unavailability of BAL cytology or FB recordings. Chronic/recurrent cough was the commonest indication for FB (75%). The median age was 3 years (IQR, 1.5-5.3 years). Secretion amount (r = 0.42) and color (r = 0.46), mucosal oedema (r = 0.42), and erythema (r = 0.30) significantly correlated with BAL neutrophil%, P < .0001. The highest area under ROC (aROC) was obtained by the addition of the scores of all features excluding pallor (aROC = 0.84; 95% CI, 0.76-0.90) with airway neutrophilia (defined as BAL neutrophil% of >10%). CONCLUSION: This prospective study has developed the first validated bronchitis scoring tool in children based on bronchoscopic visual inspection of airways. Further validation in other cohorts is however required.