Thoracic Insufficiency Syndrome Research Articles

Characterizing Lung Parenchymal Aeration via Standardized Signal Intensity from Free-breathing 4D Dynamic MRI in Phantoms, Healthy Children, and Pediatric Patients with Thoracic Insufficiency Syndrome.

Purpose To investigate free-breathing thoracic bright-blood four-dimensional (4D) dynamic MRI (dMRI) to characterize aeration of parenchymal lung tissue in healthy children and patients with thoracic insufficiency syndrome (TIS). Materials and Methods All dMR images in patients with TIS were collected from July 2009 to June 2017. Standardized signal intensity (sSI) was investigated, first using a lung aeration phantom to establish feasibility and sensitivity and then in a retrospective research study of 40 healthy children (16 male, 24 female; mean age, 9.6 years ± 2.1 [SD]), 20 patients with TIS before and after surgery (11 male, nine female; mean age, 6.2 years ± 4.2), and another 10 healthy children who underwent repeated dMRI examinations (seven male, three female; mean age, 9 years ± 3.6). Individual lungs in 4D dMR images were segmented, and sSI was assessed for each lung at end expiration (EE), at end inspiration (EI), preoperatively, postoperatively, in comparison to normal lungs, and in repeated scans. Results Air content changes of approximately 6% were detectable in phantoms via sSI. sSI within phantoms significantly correlated with air occupation (Pearson correlation coefficient = -0.96 [P < .001]). For healthy children, right lung sSI was significantly lower than that of left lung sSI (at EE: 41 ± 6 vs 47 ± 6 and at EI: 39 ± 6 vs 43 ± 7, respectively; P < .001), lung sSI at EI was significantly lower than that at EE (P < .001), and left lung sSI at EE linearly decreased with age (r = -0.82). Lung sSI at EE and EI decreased after surgery for patients (although not statistically significantly, with P values of sSI before surgery vs sSI after surgery, left and right lung separately, in the range of 0.13-0.51). sSI varied within 1.6%-4.7% between repeated scans. Conclusion This study demonstrates the feasibility of detecting change in sSI in phantoms via bright-blood dMRI when air occupancy changes. The observed reduction in average lung sSI after surgery in pediatric patients with TIS may indicate postoperative improvement in parenchymal aeration. Keywords: MR Imaging, Thorax, Lung, Pediatrics, Thoracic Surgery, Lung Parenchymal Aeration, Free-breathing Dynamic MRI, MRI Intensity Standardization, Thoracic Insufficiency Syndrome Supplemental material is available for this article. © RSNA, 2024.

Reconstruction method for massive lateral chest wall sarcoma using titanium plates and mesh: a case report

BackgroundVery large chest wall resections can lead to acute thoracic insufficiency syndrome due to the interdependence of lung expansion and thoracic volume. Chest wall tumor surgeries often encounter complications, with the size of the chest wall defect being a significant predictor. Several methods for large chest wall reconstruction have been described, aiming to provide stability, prevent flail chest, and ensure airtight closure. However, no single method fulfills all requirements. Composite chest wall reconstruction using titanium plates and Gore-Tex patches has shown the potential to minimize physiologic abnormalities caused by extensive defects.Case presentationA 42-year-old man with myxofibrosarcoma underwent multiple surgeries, chemotherapies, and radiation therapies due to repeated local recurrences. After right arm amputation and resection of the right third to fifth ribs, a local recurrence was detected. A 30 × 40 cm chest wall defect was resected en bloc, and a titanium plate was used for three-dimensional formability, preventing flail chest and volume loss. The Gore-Tex patch was then reconstructed into an arch shape, allowing lateral thoracic mobility. The patient recovered well and did not experience respiratory dysfunction or local recurrence but later succumbed to distant metastasis.ConclusionsIn this case, the combination of a titanium plate and a Gore-Tex patch proved effective for reconstructing massive lateral chest wall defects. The approach provided stability, preserved thoracic volume, and allowed for lateral mobility. While the patient achieved a successful outcome in terms of local recurrence and respiratory function, distant metastasis remained a challenge for myxofibrosarcoma patients, and its impact on long-term prognosis requires further investigation. Nevertheless, the described procedure offers promise for managing extensive chest wall defects.

A novel growth-friendly system alleviates pulmonary dysplasia in early-onset scoliosis combined with thoracic insufficiency syndrome: Radiological, pathological, and transcriptomic assessments

BackgroundThe posterior procedure utilizing growth-friendly techniques is the golden standard for patients with early-onset scoliosis combined with thoracic insufficiency syndrome (EOS + TIS). Pulmonary hypoplasia is the main cause of dying prematurely in the EOS + TIS. This study assessed the therapeutic impact of a novel growth-friendly system on the pulmonary development of piglet's EOS + TIS model. MethodsThe animal procedure period lasts 12 weeks, of which the construction of the EOS + TIS was performed at 0–8 weeks, and implantation of a novel growth-friendly system was applied at 8–12 weeks. During the animal procedure, X-rays and CT were performed to observe scoliosis, thorax, and lungs. After 12 weeks, pathological changes in lung tissue were assessed using HE and IHC staining. RNA-seq characterized novel growth-friendly system-associated differentially expressed genes (DEGs) and validated using RT-qPCR, western blotting, and IHC. ResultsImplantation of the novel growth-friendly system increased body weight, body length, and total lung volume, as well as decreased the coronal and sagittal Cobb angles for the EOS + TIS model. It also ameliorated EOS + TIS-induced thickening of the alveolar wall, increased alveolar spaces, and decreased alveolar number and diameter. In lung tissue, a total of 790 novel growth-friendly system-associated DEGs were identified, and they were mainly involved in the regulation of immune, inflammatory, calcium transport, and vascular development. Among these DEGs, BDKRB1, THBS1, DUSP1, IDO1, and SPINK5 were hub genes, and their differential expression was consistent with RNA-seq results in lung tissues. ConclusionThe novel growth-friendly system has mitigated scoliosis and pulmonary hypoplasia in the EOS + TIS model. We further elucidate the molecular mechanisms underlying the amelioration of pulmonary hypoplasia.

Increase in Early Onset Scoliosis Publications in Major Orthopaedic and Spine Journals: 2005-2020

Study Design: Retrospective review Purpose: To quantify trends in published research in 8 major orthopaedic and spine journals related to Early Onset Scoliosis (EOS) from 2005-2020. We also investigated publication trends in specific subtopics within EOS research. Methods: The electronic archives of 8 journals (Spine, European Spine Journal, Journal of Children’s Orthopaedics, Spine Deformity, Journal of Pediatric Orthopaedics, Journal of Pediatric Orthopaedics B, The Journal of Bone and Joint Surgery-American Volume and The Bone and Joint Journal) were queried for articles published from 2005-2020 containing search terms particular to the following subtopics of EOS research: congenital scoliosis, infantile scoliosis, thoracic insufficiency syndrome, scoliosis casting, Traditional Growing Rod, Vertical Expandable Prosthetic Titanium Rib, Magnetically Controlled Growing Rod and EOS in general. Results were screened to exclude editorials, conference papers and corrections. Included EOS articles were aggregated and analyzed with respect to journal, year of publication and subtopic. Results: From 2005-2020, a total of 32,000 publications were identified, of which 1,818 (5.7%) were qualified as EOS articles by the presence of at least one search term. The annual number of EOS articles increased from 60 in 2005 to 157 in 2020 and the annual ratio of EOS articles to total publications increased from 4.1% to 7.9%. Congenital spine-related terms matched to the greatest number of articles, while implant-related terms collectively experienced the greatest percentage increase in matching articles per year. Conclusion: The number of EOS articles published in 8 major orthopaedic and spine journals increased in both absolute and relative terms from 2005-2020. Implant-related subtopics saw the greatest increase.

The effectiveness of growth-friendly systems in the treatment of early onset scoliosis: a systematic review

Objective. To perform a systematic analysis of the literature evaluating the effectiveness of growth-friendly systems in the treatment of early onset scoliosis.Material and Methods. A subject search was conducted in the Google Scholar database for the terms “growing rods”, “early onset scoliosis”, “treatment”, “surgery” and “growth-friendly” using AND or OR logical operators with a search depth of 10 years. At the first stage, 824 abstracts of publications were selected. The second stage of search was carried out in accordance with the PICOS criteria, 38 abstracts of original studies, case series and reviews of surgical techniques for spinal deformity correction with preservation of growth potential were selected. The evaluation criteria were divided into four groups: general data, correction of the frontal and sagittal components of the deformity, complications and unplanned scenarios.Results. In the analyzed studies, gender equality of distribution was observed, and the average age at the time of the primary operation was 6.6 years for patients with traditional growing rods (TGR) and Schilla/Luque trolley and 4.9 years for patients with Vertical Expandable Prosthetic Titanium Rib (VEPTR). From the point of view of the magnitude of spinal deformity correction, the VEPTR systems demonstrated the minimum result (18 % correction), and the TGR and Schilla results were comparable (42.1 and 53.1 %, respectively), as well as the indicators of the dynamics of body lengthening.Conclusion. The use of VEPTR systems is associated with a high risk of complications and a somewhat lower efficiency of spinal deformity correction, however, VEPTR is indispensable in the treatment of thoracic insufficiency syndrome, as well as severe deformities of the axial skeleton in young children using non-vertebral fixation points. Growth modulation systems (Schilla and Luque trolley) showed deformity correction results similar to those of TGR.

Auto-segmentation of thoraco-abdominal organs in free breathing pediatric dynamic MRI.

Quantitative analysis of the dynamic properties of thoraco-abdominal organs such as lungs during respiration could lead to more accurate surgical planning for disorders such as Thoracic Insufficiency Syndrome (TIS). This analysis can be done from semi-automatic delineations of the aforesaid organs in scans of the thoraco-abdominal body region. Dynamic magnetic resonance imaging (dMRI) is a practical and preferred imaging modality for this application, although automatic segmentation of the organs in these images is very challenging. In this paper, we describe an auto-segmentation system we built and evaluated based on dMRI acquisitions from 95 healthy subjects. For the three recognition approaches, the system achieves a best average location error (LE) of about 1 voxel for the lungs. The standard deviation (SD) of LE is about 1-2 voxels. For the delineation approach, the average Dice coefficient (DC) is about 0.95 for the lungs. The standard deviation of DC is about 0.01 to 0.02 for the lungs. The system seems to be able to cope with the challenges posed by low resolution, motion blur, inadequate contrast, and image intensity non-standardness quite well. We are in the process of testing its effectiveness on TIS patient dMRI data and on other thoraco-abdominal organs including liver, kidneys, and spleen.

Effects of spinal deformities on lung development in children: a review

Scoliosis before the age of 5 years is referred to as early-onset scoliosis (EOS). While causes may vary, EOS can potentially affect respiratory function and lung development as children grow. Moreover, scoliosis can lead to thoracic insufficiency syndrome when aggravated or left untreated. Therefore, spinal thoracic deformities often require intervention in early childhood, and solving these problems requires new methods that include the means for both deformity correction and growth maintenance. Therapeutic strategies for preserving the growing spine and thorax include growth rods, vertically expandable titanium artificial ribs, MAGEC rods, braces and casts. The goals of any growth-promoting surgical strategy are to alter the natural history of cardiorespiratory development, limit the progression of underlying spondylarthrosis deformities and minimize negative changes in spondylothorax biomechanics due to the instrumental action of the implant. This review further elucidates EOS in terms of its aetiology, pathogenesis, pathology and treatment.

A porcine model of early-onset scoliosis combined with thoracic insufficiency syndrome: Construction and transcriptome analysis

BackgroundEarly-onset scoliosis (EOS) is a scoliosis deformity caused by various reasons before the age of 10 years and is often combined with thoracic insufficiency syndrome (TIS) causing patients with difficulty in securing lung growth in the thoracic cage. Currently, there is a shortage of effective large animal models for evaluating EOS + TIS in therapeutic studies. Consequently, we propose to construct a porcine EOS + TIS model and evaluate its transcriptome changes by RNA sequencing. MethodsPiglets were constructed using unilateral posterior spine-tethering and ipsilateral rib-tethering in the EOS + TIS model, and X-ray and computed tomography (CT) were performed to assess growth changes in the spine, thoracic cage and lungs. The H&E and Masson staining was performed for pathological analysis of lung tissue. After RNA sequencing of lung tissues, data were analyzed for differential expression of mRNA, functional enrichment analysis (GO, KEGG and GSEA) and protein–protein interaction (PPI) network construction, and differential expression of hub gene was verified by RT-qPCR. ResultsIn the model group, growth (body weight and length) of piglets was significantly delayed; fusion of ribs occurred and cobb angle changes in the coronal and sagittal planes were significantly enlarged; total lung volume (TLV) was significantly reduced, especially at the T7-T10 level. Pathological analysis revealed that, in the model lung tissue, the alveolar wall of was poorly perfused, the alveolar space was enlarged, the number and size of alveoli were significantly reduced, and it was accompanied by collagen fiber deposition. Moreover, a total of 432 differentially expressed mRNAs (DE-mRNAs) were identified in model lung tissues, which contained 262 down-regulated and 170 up-regulated DE-mRNAs, and they were mainly involved in the regulation of immunity, inflammation, cell cycle and extracellular matrix. A PPI network containing 71 nodes and 158 edges was constructed based on all DE-mRNAs, and JUN, CCL2, EGR1, ATF3, BTG2, DUSP1 and THBS1 etc. were hub gene. ConclusionsOverall, we constructed a porcine model that was capable of replicating the common clinical features of EOS + TIS such as rib fusion, asymmetric thoracic cage, increased cobb angle, decreased TLV, and pulmonary hypoplasia. Also, we revealed transcriptomic changes in the EOS + TIS model that may cause pulmonary hypoplasia.

A transcriptome analysis based on a novel porcine model of early-onset scoliosis combined with thoracic insufficiency syndrome

A transcriptome analysis based on a novel porcine model of early-onset scoliosis combined with thoracic insufficiency syndrome

Jarcho–Levin syndrome: A rare case of thoracic insufficiency syndrome in a newborn

Jarcho–Levin syndrome: A rare case of thoracic insufficiency syndrome in a newborn

Assessment of Regional Functional Effects of Surgical Treatment in Thoracic Insufficiency Syndrome via Dynamic Magnetic Resonance Imaging.

Quantitative regional assessment of thoracic function would enable clinicians to better understand the regional effects of therapy and the degree of deviation from normality in patients with thoracic insufficiency syndrome (TIS). The purpose of this study was to determine the regional functional effects of surgical treatment in TIS via quantitative dynamic magnetic resonance imaging (MRI) in comparison with healthy children. Volumetric parameters were derived via 129 dynamic MRI scans from 51 normal children (November 2017 to March 2019) and 39 patients with TIS (preoperatively and postoperatively, July 2009 to May 2018) for the left and right lungs, the left and right hemi-diaphragms, and the left and right hemi-chest walls during tidal breathing. Paired t testing was performed to compare the parameters from patients with TIS preoperatively and postoperatively. Mahalanobis distances between parameters of patients with TIS and age-matched normal children were assessed to evaluate the closeness of patient lung function to normality. Linear regression functions were utilized to estimate volume deviations of patients with TIS from normality, taking into account the growth of the subjects. The mean Mahalanobis distances for the right hemi-diaphragm tidal volume (RDtv) were -1.32 ± 1.04 preoperatively and -0.05 ± 1.11 postoperatively (p = 0.001). Similarly, the mean Mahalanobis distances for the right lung tidal volume (RLtv) were -1.12 ± 1.04 preoperatively and -0.10 ± 1.26 postoperatively (p = 0.01). The mean Mahalanobis distances for the ratio of bilateral hemi-diaphragm tidal volume to bilateral lung tidal volume (BDtv/BLtv) were -1.68 ± 1.21 preoperatively and -0.04 ± 1.10 postoperatively (p = 0.003). Mahalanobis distances decreased after treatment, suggesting reduced deviations from normality. Regression results showed that all volumes and tidal volumes significantly increased after treatment (p < 0.001), and the tidal volume increases were significantly greater than those expected from normal growth for RDtv, RLtv, BDtv, and BLtv (p < 0.05). Postoperative tidal volumes of bilateral lungs and bilateral hemi-diaphragms of patients with TIS came closer to those of normal children, indicating positive treatment effects from the surgical procedure. Quantitative dynamic MRI facilitates the assessment of regional effects of a surgical procedure to treat TIS. Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Врожденный лордоз и лордосколиоз: состояние проблемы (обзор литературы)

the dorsal part of the vertebrae and normal growth of the ventral part. The most common nosological variant of the defect is lordoscoliotic deformity of the thoracic spine, which often occurs due to syndromic defects (spondylocostal dysostosis) and systemic diseases of the musculoskeletal system (arthrogryposis). Along with the vertebral syndrome, the pathological complex in congenital lordosis of the thoracic or thoracolumbar spine includes thoracic insufficiency syndrome, which in the overwhelming cases leads to the development of respiratory failure caused by bronchial obstruction. The purpose of the study is to summarize information and analyze literature data on a rare pathology of the spine, which is clinically manifested by the formation of thoracic lordosis due to congenital anomaly in the development of the vertebrae. Materials and methods An analysis of the literature on the diagnosis and treatment of congenital lordosis and lordoscoliosis in children was carried out. The depth of the search was more than 100 years. Inclusion criteria: presence of lordotic deformity of the thoracic, cervicothoracic or thoracolumbar spine. Results and discussion Respiratory failure in this group of patients develops due to reduction in the anteroposterior size of the chest (an increase in the chest penetration index), a decrease in the height of the thoracic spine, changes in the mechanics of rib movements, bronchial obstruction, worsening ventilation and perfusion on the convex side of the deformity. The leading component of disability and impairment of the quality of life of patients is respiratory failure syndrome. A decrease in lung function, primarily due to reduction in VC, is directly proportional to the magnitude of the deformation of the spine and chest. Surgical correction of spinal and chest deformity is the main component of treatment for this group of patients. Surgical treatment consists in the mandatory multilevel mobilization of all three columns of the spine (preferably combined access) and bilateral resection of the ribs to reduce chest rigidity. Postoperative respiratory support is critical in respiratory failure. Conclusion Congenital spinal deformities in the form of thoracic lordosis and lordoscoliosis are extremely rare. The key aspects of treatment are the fight against respiratory failure and the selective choice of surgical technologies for deformity correction with a trend towards simultaneity of interventions. The literature review confirmed the insufficient knowledge on the issues of this pathology.

Early-onset scoliosis: a narrative review.

Early-onset scoliosis (EOS) is defined as any spinal deformity that is present before 10 years old, regardless of etiology.Deformity must be evaluated based on the intercorrelation between the lungs, spine, and thorax.Curvatures of early-onset have increased risk of progression, cardiorespiratory problems, and increased morbidity and mortality.Progression of the deformity may produce thoracic insufficiency syndrome, where a distorted thorax is unable to support normal respiratory function or lung growth.Management and treatment of EOS should pursue a holistic approach in which the psychological impact and quality of life of the patient are also taken into consideration.Growth-friendly surgical techniques have not met the initial expectations of correcting scoliotic deformity, promoting thoracic growth, and improving pulmonary function.

QdMRI: A system for comprehensive analysis of thoracic dynamics via dynamic MRI.

Quantitative thoracic dynamic magnetic resonance imaging (QdMRI), a recently developed technique, provides a potential solution for evaluating treatment effects in thoracic insufficiency syndrome (TIS). In this paper, we integrate all related algorithms and modules during our work from the past 10 years on TIS into one system, named QdMRI, to address the following questions: (1) How to effectively acquire dynamic images? For many TIS patients, subjects are unable to cooperate with breathing instructions during image acquisition. Image acquisition can only be implemented under free-breathing conditions, and it is not feasible to use a surrogate device for tracing breathing signals. (2) How to assess the thoracic structures from the acquired image, such as lungs, left and right, separately? (3) How to depict the dynamics of thoracic structures due to respiration motion? (4) How to use the structural and functional information for the quantitative evaluation of surgical TIS treatment and for the design of the surgery plan? The QdMRI system includes 4 major modules: dynamic MRI (dMRI) acquisition, 4D image construction, image segmentation (from 4D image), and visualization of segmentation results, dynamic measurements, and comparisons of measurements from TIS patients with those from normal children. Scanning/image acquisition time for one subject is ~20 minutes, 4D image construction time is ~5 minutes, image segmentation of lungs via deep learning is 70 seconds for all time points (with the average DICE 0.96 in healthy children), and measurement computation time is 2 seconds.

Monitoring and Management of Fibrodysplasia Ossificans Progressiva: Current Perspectives.

Fibrodysplasia ossificans progressiva (FOP), sometimes known as myositis ossificans progressiva, is an ultra-rare disease in which bone is formed in muscular tissue, tendons and ligaments. This is known as heterotopic ossification (HO). FOP is caused by a heterozygous mutation in the highly conserved ACVR1/ALK2 gene which affects about 1 in 1.5–2 million individuals. At birth, patients with the predominant R206H mutation only exhibit a bilateral hallux valgus. During childhood, heterotopic bone formation develops in a typical pattern, affecting the axial muscles first before appendicular body parts are involved. HO can start spontaneously but is often elicited by soft tissue trauma or medical procedures. After soft tissue injury, an inflammatory process called a flare-up can start, followed by the formation of HO. HO leads to a limited range of motion, culminating in complete ankylosis of nearly all joints. As a result of HO surrounding the thorax, patients often suffer from thoracic insufficiency syndrome (TIS). TIS is the most common cause of a limited life expectancy for FOP patients, with a median life expectancy of 56 years. Management is focused on preventing soft-tissue injury that can provoke flare-ups. This includes prevention of iatrogenic damage by biopsies, intramuscular injections and surgery. Anti-inflammatory medication is often started when a flare-up occurs but has a poor basis of evidence. Several forms of potential treatment for FOP are being researched in clinical trials. Progression of the disease is monitored using CT and 18F-NaF PET/CT combined with functional assessments. Patients are regularly evaluated for frequently occurring complications such as restrictive lung disease. Here, we review the current management, monitoring and treatment of FOP.

Surgical and Nonsurgical Factors Associated with Salvaging Exposed Vertical Expandable Prosthetic Titanium Rib Hardware.

Vertical expandable prosthetic titanium rib (VEPTR) devices were designed to treat childhood scoliosis and thoracic insufficiency syndrome. Although they have drastically reduced patient mortality, they present a profound subcutaneous hardware burden. The authors examined the surgical and nonsurgical factors associated with salvage of VEPTR hardware exposures. Between 2014 and 2020, a prospective institutional database was queried for patients with VEPTR hardware complications who required soft-tissue reconstruction. Hardware salvage was considered successful if reconstruction allowed the hardware to be retained until the next VEPTR expansion. Fifty-eight patients required VEPTR hardware salvage. Hardware complications were successfully salvaged in 62.1 percent of patients at 60.0 percent of operative sites. Neuromuscular scoliosis (p = 0.041) and nonambulatory status (p = 0.018) were factors associated with VEPTR hardware salvage failure, whereas congenital scoliosis was associated with successful hardware salvage (p = 0.012) and preventing need for immediate hardware removal (p = 0.049). Exposed hardware, as compared to threatened exposure, was more likely to require immediate removal (p = 0.045) and result in unsuccessful hardware salvage (p = 0.015). Local and regional muscle flaps were able to prevent VEPTR hardware removal in the majority of patients, even in the setting of infection, immobility, incontinence, and multiple systemic comorbidities. Patients with neuromuscular scoliosis and nonambulatory status were at increased risk for failure, whereas those with incontinence and low body mass index trended toward increased risk of failure. Threatened exposure was associated with higher rates of salvage than exposed hardware, and thus earlier referral to plastic surgeons for soft-tissue salvage may be advised. Risk, III.

Assessment of the respiratory system in children with congenital scoliosis by impulse oscillometry and computed tomography (preliminary results)

BACKGROUND: Segmentation disorder of the vertebral body lateral surfaces and rib synostosis are severe variants of congenital pathology of the spine and thorax. They lead to the development of thoracic insufficiency syndrome and are manifested by the inability of the thorax to provide normal respiratory mechanics.&#x0D; AIM: This study presents the preliminary results of functional and radiological (CT-morphometric) methods of lung examinations in patients with congenital thoracic spine scoliosis with impaired segmentation of the lateral surfaces of the vertebral bodies and unilateral rib synostosis.&#x0D; MATERIALS AND METHODS: This design is represented by a small clinical series. This study is a prospective study of 10 patients aged 3 to 7 years with congenital spinal deformity, with impaired segmentation of the lateral surfaces of vertebral bodies and unilateral rib synostosis. This paper presents the preliminary results of the pulmonary function assessment by pulse oscillometry and CT morphometry in a 3D reconstruction of multispiral computer tomography (MSCT) of the thorax.&#x0D; RESULTS: The study of respiratory function using pulse oscillometry revealed no respiratory impairment in seven observations, also reflected in the CT morphometry results. According to the Institute of Medicine (IOM), three children with detected ventilatory abnormalities showed the following parameters with the most significant changes: total respiratory impedance, resonance frequency, and frequency dependence of the resistive component. In all patients, the morphometric indexes of the lung scoring revealed during 3D modeling of the lung were completely consistent with the results of the lung function study by the IOM method.&#x0D; CONCLUSIONS: Further study of the problem of respiratory function assessment in children with congenital scoliosis seems promising in diagnostic terms and for evaluating effective surgical treatment.

Dynamic Contrast Magnetic Resonance Lymphangiography Localizes Lymphatic Leak to the Duodenum in Protein-Losing Enteropathy.

Protein-losing enteropathy (PLE) is a disorder of intestinal lymphatic flow resulting in leakage of protein-rich lymph into the gut lumen. Our primary aim was to report the imaging findings of dynamic contrast magnetic resonance lymphangiography (DCMRL) in patients with PLE. Our secondary objective was to use these imaging findings to characterize lymphatic phenotypes. Single-center retrospective cohort study of patients with PLE unrelated to single-ventricle circulation who underwent DCMRL. We report imaging findings of intranodal (IN), intrahepatic (IH), and intramesenteric (IM) access points for DCMRL. Nineteen patients 0.3-58 years of age (median 1.2 years) underwent 29 DCMRL studies. Primary intestinal lymphangiectasia (PIL) was the most common referring diagnosis (42%). Other etiologies included constrictive pericarditis, thoracic insufficiency syndrome, and genetic disorders. IN-DCMRL demonstrated a normal central lymphatic system in all patients with an intact thoracic duct and localized duodenal leak in one patient (1/19, 5%). IH-DCMRL detected a duodenal leak in 12 of 17 (71%), and IM-DCMRL detected duodenal leak in 5 of 6 (83%). Independent of etiology, lymphatic leak was only visualized in the duodenum. In patients with PLE, imaging via DCMRL reveals that leak is localized to the duodenum regardless of etiology. Comprehensive imaging evaluation with three access points can provide detailed information about the site of duodenal leak.

The Use of VEPTR in Congenital Scoliosis

Background: Congenital scoliosis is nowadays addressed by many surgical solutions. There are rare cases presenting with mixed vertebral defects associated with Thoracic Insufficiency Syndrome (TIS). The presence of mixed vertebral defects may present with a very high progressive potential, inducing a severe scoliotic curve which impairs the development of the thoracic cage. Additionally, these cases may associate rib fusions which will further impair the development of the lung in these patients. The unique surgical solution in these cases is represented by VEPTR (Vertical Expandable Prosthesis Titanium Rib) devices able to expand the thorax and to control the scoliotic curve. Material and methods: The surgical technique of the VEPTR device in a rib-to-spine construct consists in a distraction based device able to expand the thorax on the concave side of the scoliosis by consecutive distractions and, secondary, to control de scoliotic curve. The upper module of the device is placed on the first, second and/or third rib and the lower module is fixed to the upper lumbar spine. The construct is completed with the expansion module which allows distractions (1/2 or 1 cm for each distraction). The patients undergo every 4-6 months consecutive distractions until skeletal maturity when definitive spinal fusion is performed. Results: The VEPTR device in standard constructs with placement as recommended by the developer proved to be efficient in controlling congenital scoliotic curves and thoracic expansion. Unusual placements of the device complicated the evolution of patients with congenital scoliosis and required additional surgical procedures to correct the deformities and to try to ensure remnant spinal growth. Conclusions: The VEPTR device has strict indications, congenital scoliosis with TIS being one of them. Proper indication and surgical procedure will aid the patients all along spinal and thoracic growth, in order to obtain a lung and spinal development as close to normal as possible in order to avoid premature death due to TIS.

OFx: A method of 4D image construction from free-breathing non-gated MRI slice acquisitions of the thorax via optical flux.

Since real-time 4D dynamic magnetic resonance imaging (dMRI) methods with adequate spatial and temporal resolution for imaging the pediatric thorax are currently not available, free-breathing slice acquisitions followed by appropriate 4D construction methods are currently employed. Self-gating methods, which extract breathing signals only from image information without any external gating technology, have much potential for this purpose, such as for use in studying pediatric thoracic insufficiency syndrome (TIS). Patients with TIS frequently suffer from extreme malformations of the chest wall, diaphragm, and spine, leading to breathing that is very complex, including deep or shallow respiratory cycles. Existing 4D construction methods cannot perform satisfactorily in this scenario, and most are not fully automatic, requiring manual interactive operations. In this paper, we propose a novel fully automatic 4D image construction method based on an image-derived concept called flux to address these challenges. We utilized 25 dMRI data sets from 25 pediatric subjects with no known thoracic anomalies and 58 dMRI data sets from 29 patients with TIS where each patient had a dMRI scan before and after surgery. A time sequence of 80 slices are acquired at each sagittal location continuously at a rate of ~480ms per slice under free-breathing conditions, with 30-40 sagittal locations across the chest for each subject depending on the thoracic size. In our approach, we first extract the breathing signal for each sagittal location based on the flux of the optical flow vector field of the body region from the image time series. Here, for each time point of respiratory phase, the net flux of the body region can be regarded as the flux going into or out of the body region, which we term Optical Flux (OFx). OFx provides a very robust representation of the real breathing motion of the thorax. OFx allows us to perform a full analysis of all respiratory cycles, extract only normal cycles in a robust manner, and map all extracted normal cycles on to one cosine respiration model for each sagittal location. Subsequently, we re-sample one normal cycle from the respiration model for each location independently. The normal cycle models associated with the different sagittal locations are finally composited to form the final constructed 4D image. We employ several metrics to evaluate the quality of the 4D construction results: Eie - error in locating time instants corresponding to end inspiration and end expiration; Eto - deviation from correct temporal order in each detected normal cycle; Ess - deviation in spatial smoothness; and Esc - deviation from spatial continuity as scored by a reader. The means and standard deviations of these metrics for normal subjects and TIS patients are found to be, respectively: Eie: 0.25±0.05 and 0.38±0.16 in units of time instance (ideal value=0); Eto: 2.7% ± 2.3% and 1.8%±2% (ideal value=0%); Ess: 0.5±0.17 and 0.54±0.25 in pixel units (ideal value=0); Esc: 4.6±0.48 and 4.56±0.98 (score range: best=5, worst=1). The results show that the OFx method achieves excellent spatial and temporal continuity and its yield was 100% meaning that it successfully performed 4D construction on every data set tested. Compared to a recently published method, OFx is fully automatic requiring about 5min of computational time per study starting from acquired dMRI scans. The method achieves high temporal and spatial continuity even on complex TIS data sets that include many abnormal respiratory cycles. A new 4D dMRI construction method based on the concept of optical flux is presented which is fully automatic and very robust in deriving respiratory signals purely from dynamic image sequences even when presented with complex breathing patterns due to severe disease conditions like TIS. Evaluations show that its accuracy is comparable to the variations found in manual annotations. An important characteristic of the method is that it is independent of the number of sagittal locations used in the construction process, which suggests that it is applicable to imaging techniques where data are acquired at only a few sagittal locations instead of the full width of the thorax. The method is not tied to any specific imaging modality, as demonstrated in this paper on not just dMRI but dynamic computed tomography (CT) as well.