Intravascular Tumor Extension and Pulmonary Tumor Embolism in Children With Solid Malignancies: Is There a Role for Inferior Vena Cava Filters?

Intravascular tumor extension is an uncommon complication of solid malignancies that, when present in the inferior vena cava (IVC), can result in fatal pulmonary tumor embolism. Currently, neoadjuvant chemotherapy and surgery are the mainstays of treatment; however, there are no consensus guidelines for management. We describe three cases of pediatric solid malignancies with associated IVC extension and pulmonary tumor embolism. We hypothesize that there is scope for IVC filter placement in such cases to mitigate the risk of fatal pulmonary tumor embolism.

Presentation, treatment, and outcome of renovascular hypertension below 2 years of age.

Renovascular hypertension in most cases requires endovascular treatment and/or surgery. This is technically much more difficult in small children and there is very limited published knowledge in this age group. We here present treatment and outcome of young children with renovascular hypertension at our institution. Children below 2 years of age, with renovascular hypertension between January 1998 and March 2020 were retrospectively reviewed. Demographics and treatment modalities were noted. Primary outcome was blood pressure within a week after the procedures and at last available visit. Sixty-six angiographies were performed in 34 patients. Median age at time of first angiography was 1.03 (interquartile range (IQR) 0.4-1.4) years and systolic blood pressure at presentation 130 (IQR 130-150) mm Hg. Thirty-eight percent (13/34) of children were incidentally diagnosed and 18% (6/34) presented with heart failure. Twenty-six (76%) children had main renal artery stenosis and 17 (50%) mid-aortic syndrome. Seventeen (50%) children showed intrarenal, six (18%) mesenteric, and three (9%) cerebrovascular involvement. Twenty patients underwent 45 percutaneous transluminal angioplasty procedures and seven children surgeries. In 44% of the 16 patients who underwent only percutaneous transluminal angioplasty blood pressure was normalized, 38% had improvement on same or decreased treatment and 19% showed no improvement. Complications were seen in 7.5% (5/66) of angiographies. In four of the seven (57%) children who underwent surgery blood pressure was normalized, two had improved (29%) and one unchanged (14%) blood pressure. CONCLUSION: In small children with renovascular hypertension below the age of 2 years, percutaneous transluminal angioplasty caused significant improvement in blood pressure with low complication profile. Surgery can be recommended where percutaneous transluminal angioplasty and medical treatments failed. WHAT IS KNOWN: • Renovascular hypertension is diagnosed in all age groups from a few weeks of life until adulthood. • Both angioplasty and surgery are significantly more difficult to perform in small children and the published information on short and long-term outcome in these children is very scarce. WHAT IS NEW: • Children below the age of two years can safely and successfully undergo selective renal angiography and also safely be treated with angioplasty. • We here present a large group of babies and infants where angioplasty and in some cases surgery effectively and safely improved their blood pressure.

Pediatric interventional radiology - does it add value?

Although attempts have been made to show that pediatric interventional radiology adds value in children's hospitals, none has been particularly persuasive. An analysis of individual procedures would seem to be the most scientific approach, but there are numerous problems, including the effects that different health care systems have on clinical practice and the difficulty of generalizing the results of a single-center study to other hospitals, even within the same type of health care system. It is unsurprising that there are no published randomized controlled trials comparing both the costs and outcomes of specific pediatric interventional radiology procedures with surgical alternatives, and in fact these may not be feasible. There is only anecdotal evidence of the value of pediatric interventional radiology in multidisciplinary teams in children's hospitals. Currently, the best justification may be the counterfactual: demonstrating what can go wrong if pediatric interventional radiology expertise is not available.

Imaging of Airway Obstruction in Children.

Various imaging techniques may be used to diagnose airway obstruction in children. Digital radiography, computed tomography and magnetic resonance imaging are the most important modalities, but the choice of technique will depend on the level and nature of suspected obstruction, as well as patient-specific factors such as age and ability to cooperate. This review examines the forms of airway obstruction that are commonly encountered in childhood.

Interventional radiology in the airway in children.

Interventional procedures in the airway can be performed in interventional radiology suites or the operating room, by radiologists or other specialists. The most common therapeutic interventions carried out by radiologists are balloon dilatation, stenting, and the treatment of certain airway fistulas. These operations can be very challenging for anesthetists in terms of planning, airway management, the identification and treatment of procedural complications and postoperative care. In particular, a multidisciplinary approach to decision-making and planning is important to obtain the best results.

Self-expanding esophageal stents for the management of benign refractory esophageal strictures in children: A systematic review and review of outcomes at a single center.

BACKGROUND: This study aimed to evaluate our outcomes and complication rate following placement of self-expanding esophageal stents in children for the management of refractory esophageal strictures and comparing these to the existing literature. METHODS: Outcomes following placement of stents in consecutive patients under 18 years at a single center from 2003 to 2018 were reviewed. A PRISMA-guided systematic review was conducted identifying studies with 5 or more children evaluating self-expanding stents published from 1975 to 2018. Endpoints for both the retrospective and systematic reviews were the requirement for further intervention and stent-associated complications. RESULTS: 25 patients received 65 stents. There were 12 caustic injury-related strictures (48%), 9 anastomotic strictures (36%), and 4 esophagitis-related strictures (16%). Four patients were lost to follow-up. 19/21 patients (90%) required further intervention, and 8/21 (38%) had esophageal replacement. Nine studies, all case series, were included in the systematic review. 97 patients received 160 stents for esophageal strictures and/or perforation. 36 out of 69 patients (52%) with strictures required no further treatment post-stenting, and 22/29 (76%) of esophageal perforations closed with stenting. CONCLUSIONS: Esophageal stents may have a role as a bridge to definitive surgery and for the management of esophageal leaks, but complete stricture resolution post-stenting is unlikely. TYPE OF STUDY: Treatment Study (Case Series with no Comparison Group) LEVEL OF EVIDENCE: Level IV.

Tracheobronchial stenting for airway malacia.

Tracheobronchomalacia is a rare but clinically troublesome condition in paediatrics. The softening of the major airways - which can include some or all of the tracheobronchial tree can lead to symptoms ranging from the minor (harsh barking cough, recurrent chest infections) to severe respiratory difficulties including prolonged ventilator support and 'near death attacks'. The causes are broadly divided into intrinsic softening of the airway wall which is considered a primary defect (e.g. syndromes; post tracheo-oesophageal fistula repair; extreme prematurity) or secondary malacia due to external compression from vascular structures or cardiac components. These secondary changes can persist even when the external compression is relieved, for example, following the repair of a pulmonary artery sling or double aortic arch. For children with severe clinical symptoms attributed to malacia, consideration is given to possible surgical remedies such as an aortopexy for short limited areas of malacia, or long term positive pressure support with CPAP either by non invasive or tracheostomy interface. More recently the role of stenting in children is receiving attention, especially with the development of newer techniques such as bioabsorbable stents which buy time for a natural history of improvement in the malacia to occur. This paper reviews the stents available and discusses the pros and cons of stenting in paediatric airway malacia.

Non-invasive imaging cannot replace formal angiography in the diagnosis of renovascular hypertension.

OBJECTIVES: Renovascular disease (RVD) is found in about 10 % of secondary childhood hypertension. Digital subtraction angiography (DSA) is the gold standard to diagnose RVD. Non-invasive imaging methods like Doppler ultrasound (US), magnetic resonance angiography (MRA), and computed tomography angiography (CTA) are increasingly used. Our aim was to evaluate the role and accuracy of US, MRA, and CTA compared to DSA in diagnosing RVD in children. PATIENTS AND METHODS: A retrospective review of 127 children with suspected renovascular hypertension was performed in children referred to Great Ormond Street Hospital between 2006 and 2014 due to clinical suspicion of renovascular hypertension and/or findings on US and/or MRA or CTA. RESULTS: Ninety-nine of 127 children (78 %) were diagnosed with renovascular disease and 80 were treated with percutaneous transluminal angioplasty during the same procedure. The median age at presentation was 5.6 (range, 2.5-10.6) years. Thirty-six children had unilateral renal artery stenosis in major extraparenchymal vessels, 47 bilateral stenosis and 16 intrarenal small vessel disease. US had a sensitivity of 63 % and specificity of 95 %. MRA and CTA were performed in 39 and 34 children, respectively. CTA sensitivity was slightly higher than that of MRA, 88 vs. 80 %, and specificity 81 vs. 63 %. CONCLUSIONS: The sensitivity of MRA and CTA is still too low to reliably rule out renovascular disease in children with a strong suspicion of this diagnosis. DSA remains the gold standard to diagnose renovascular hypertension and is recommended when clinical and laboratory criteria are highly suggestive of renovascular disease even with normal radiological investigations from non-invasive methods.

Angioplasty for renovascular hypertension in 78 children.

OBJECTIVES: To evaluate the outcome of percutaneous transluminal angioplasty (PTA) in children with renovascular hypertension (RVH) treated at a single centre over 29 years. METHODS: A retrospective study of the medical charts of all children with RVH who underwent PTA between 1984 and 2012. The primary outcome measurement was blood pressure (BP) achieved after the procedure. The BP before the procedure was compared with that at last available follow-up, 6 (range 0.6-16) years after the initial procedure. RESULTS: Seventy-eight children with median (range) age of 6.5 (0.5-17) years were studied. Twenty-three (29.5%) had an underlying syndrome, 35 (44.9%) children had bilateral renal artery stenosis (RAS), 18 (23%) intrarenal disease and 11(14%) showed bilateral RAS and intrarenal disease. Twenty (25.6%) children had mid-aortic syndrome and 14 (17.9%) cerebrovascular disease. One hundred and fourteen PTA procedures were carried out including 31 stent insertions. Following PTA, BP was improved in 49 (62.8%) children and of those 18 (23.1%) were cured. Children with involvement of only the main renal arteries showed improved BP control in 79.9% of the children with cure in 39.5%. BP was intentionally maintained above the 95th centile for age and height in four children with coexistent cerebrovascular disease. No change in BP was seen in 18 children despite observed technical success of the PTA, and in seven children due to technical failure of the procedure. CONCLUSIONS: PTA provided a clinical benefit in 62.8% of children with RVH.

The influence of stents on microbial colonization of the airway in children after slide tracheoplasty: a 14-year single-center experience.

OBJECTIVES: This study describes the microbial colonization profile of the airway in children after slide tracheoplasty (STP) with and without stents, and compares colonization to children undergoing cardiothoracic surgical procedures without airway related disease. METHODS: A 14-year retrospective single case note review was performed on patients undergoing STP and stent insertion. Nose and throat (NT) and bronchoalveolar lavage (BAL) specimens were analyzed for microbial profile and expressed as cumulative mean microorganisms per patient (MMP). RESULTS: Forty-three patients (median age ± SD 15.02 ± 31.76 months) underwent STP and 141 patients underwent cardiothoracic but no airway surgery (median age ± SD 31.7 ± 47.2 months). Sixteen patients required a stent after STP. One-hundred seventy-two positive microbial specimens were identified. The predominant 6 microorganisms were (1) Staphylococcus aureus; (2) Pseudomonas aeruginosa; (3) Haemophilus influenzae not type B; (4) Coliforms; (5) Streptococcus pneumoniae; and (6) Candida Albicans, and accounted for 128 (74%) of all positive specimens found. Children with stents had more MMP compared to children without stents after STP [4.06 ± 2.38 and 2.04 ± 2.24 MMP (P < 0.001), respectively]. Both groups of children after STP had more MMP compared to the control group (P < 0.001). Children with stents had more microbial colonization of their lower respiratory tract compared to their upper respiratory tract (3.36 ± 2.02 and 1.36 ± 0.93 MMP (P < 0.01) respectively). Staphylococcus aureus colonization of the lower respiratory tract was significantly higher in children with stents compared to children without stents after STP [0.5 and 0.15 MMP (P < 0.05) respectively]. CONCLUSIONS: This study indicates airway surgery and the subsequent use of stents to be a significant risk factor for microbial colonization of the airway in children. More specifically airway stents appear to increase colonization in the distal airway, which appears unrelated to that of the upper respiratory tract.

Renal artery revascularisation can restore kidney function with absent radiotracer uptake.

BACKGROUND: Children with renovascular hypertension often present with severe hypertension. Some children have severe obstruction of their renal arteries resulting in <10% relative function on [(99m)Tc]dimercaptosuccinic acid (DMSA) scan. Conventional treatment of these children has been nephrectomy of the poorly functioning kidney to normalise their blood pressure (BP). CASE-DIAGNOSIS/TREATMENT: We describe three children aged 20 months to 9 years with severe renal artery stenosis and severe hypertension who had radionucleotide uptake of 0% in one kidney. In one case, no renal perfusion was demonstrated by duplex ultrasound scan. Significant recovery of relative renal function of 18 to 52% was achieved after revascularisation by percutaneous angioplasty or open surgery of the obstructed renal artery. CONCLUSION: These cases illustrate that scintigraphy alone cannot be used to predict salvageable function in children with renovascular disease.

Do tracheas grow after slide tracheoplasty?

BACKGROUND: Slide tracheoplasty has become the surgical technique of choice for repair of congenital tracheal stenosis. Despite the initial reluctance regarding the ability of this "reconstructed" trachea to grow, the reduced morbidity and mortality have allowed slide tracheoplasty to be widely adopted. The aim of this study was to evaluate tracheal growth after slide tracheoplasty. METHODS: This was a retrospective study. In follow-up bronchography performed 1, 6, 12, 18, and 24 months after slide tracheoplasty, we measured the cross-sectional areas of the midtrachea and distal trachea at each investigation and correlated the measurements with the anthropomorphic factors (body weight, height, and body surface). RESULTS: Fourteen patients were enrolled in this study. The midtracheal and distal tracheal cross-sectional areas significantly increased with time (p ≤ 0.0001). The average rates of midtracheal growth were 21.0 mm(2)year in the first 6 months and 8.0 mm(2)/year in the first 2 years, and the distal trachea grew 18.5 mm(2)/year and 8.4 mm(2)/year, respectively. Regression analysis showed that both the midtrachea and the distal trachea increase significantly with weight (r(2) = 0.257, p ≤ 0.0001), height (r(2) = 0.376, p ≤ 0.0001), and body surface area (r(2) = 0.315, p ≤ 0.0001). Balloon dilation did not significantly alter the tracheal growth in the first 2 years after slide tracheoplasty. CONCLUSIONS: Slide tracheoplasty does not inhibit tracheal growth. The reconstructed trachea grows faster in the first 6 months and slows in the following 18 months. There is a positive correlation between tracheal cross-sectional area and weight, height, and body surface area.

A new morphologic classification of congenital tracheobronchial stenosis.

BACKGROUND: Congenital tracheal stenoses are rare and life-threatening anomalies, associated with considerable variation in both morphology and prognosis. They have been classified previously according to the length of the stenosis or the severity of the symptoms, but not according to bronchial involvement. METHODS: Data from patients who underwent slide tracheoplasty for long-segment (>50%) congenital tracheal stenosis were collected. We identified four different types of bronchial arborization (normal, n=52; tracheal right upper lobe bronchus, n=10; carina with "trifurcation," n=14; and unilateral bronchial and lung agenesis, n=8). Each type included congenital tracheal (above the carina) or tracheobronchial (extending below the carina) stenosis. RESULTS: Eighty-four children were enrolled in the study. Preoperative ventilation was necessary in 44 patients (52.4%; 75% in patients with a single lung), and preoperative extracorporeal membrane oxygenation was needed in 10 patients (11.9%). Preoperative tracheostomy was present in 3 patients initially treated elsewhere (3.5%), and a left pulmonary artery sling was performed in 44% (37 of 84). The overall mortality was 13% (11 of 84), 7.9% in patients with tracheal stenosis and 28.6% with tracheobronchial stenosis. No deaths occurred in patients with right upper lobe bronchus anatomy. Endoscopic procedures after slide tracheoplasty were required in 34 patients (40.4%). Stents were placed in 18 patients (21.4%), with a higher incidence in those with bronchial trifurcation (42.8%, 6 of 12). CONCLUSIONS: This classification appears useful for the morphologic characterization of congenital airway stenosis and could be the benchmark for future prospective studies on the outcome of these patients.

Infantile midaortic syndrome with aortic occlusion.

Mid aortic syndrome (MAS) is a rare condition often presenting with severe hypertension. It is characterized by narrowing of the abdominal aorta. We here describe a case of complete occlusion of the abdominal aorta presenting in infancy. This child presented at four months of age with heart failure and hypertension. CT angiogram showed total narrowing of the abdominal aorta. This was initially felt to be too severe for surgical treatment and he was planned for palliative care. We were however able to improve his blood pressure with antihypertensive agents and he underwent succesful angioplasty at five and a half months of age. He has required three further angioplasty procedures and still needs two antihypertensive agents to control his blood pressure. His renal function remains normal and at age six years he has excellent quality of life with normal growth and development. This case illustrates that the combination of medical treatment and angioplasty can give an excellent long-term treatment response even in children with extremely severe MAS. This boy now has normal blood pressure and has experienced normal growth, development and quality of life.

First experience with biodegradable airway stents in children.

PURPOSE: We here report our experience with biodegradable polydioxanone stents for tracheal narrowing in children. DESCRIPTION: Eleven custom-made polydioxanone stents were implanted in 4 patients with airway narrowing due to external compression or intrinsic collapse. The median stent diameter was 9 mm (range, 6 to 14 mm) and median length was 15 mm (range, 13 to 70 mm). EVALUATION: Narrowing was relieved initially in all cases. There was no bleeding or perforation after polydioxanone stent implantation. Size mismatching was a problem in 2 cases. Three patients needed repeat stenting after stent absorption. There was 1 death, unrelated to the stent implantation. All 3 survivors are in good clinical condition up to 12 months after first stenting. CONCLUSIONS: This pilot study shows that polydioxanone stents offer an alternative to metallic or silastic stents for collapse or external compression of the trachea in children. They may avoid the need for permanent stenting and allow subsequent growth of the airway.

Interventions in the chest in children.

The scope for image-guided intervention in the chest is very wide and encompasses procedures in the heart, pulmonary and systemic vasculature, lungs and pleural cavities, airway, and esophagus. This review describes the most important procedures that are usually performed by radiologists. Percutaneous drainage is now the most common method of treating both empyemas and lung abscesses in children. Although most lung biopsies are carried out by other means, percutaneous biopsy and localization are important alternatives for the diagnosis of focal lung lesions. Esophageal strictures are common in children and are usually best treated by balloon dilatation. The use of retrievable or biodegradable stents has recently been introduced for refractory esophageal strictures. Similarly, balloon dilatation and stenting are now increasingly used in children with stenosis or extrinsic compression of the trachea or bronchi.

Gastrointestinal intervention in children.

Interventional radiology is a rapidly growing discipline in paediatrics. Many non-vascular interventional techniques may be used in the gastrointestinal tract in children. The technically simpler and more common of these may be adopted by any paediatric radiologist with an interest in interventional radiology. Other rarer and more complex techniques are currently restricted to specialist centres with a higher overall caseload. This review emphasizes the common procedures such as oesophageal dilatation, gastrostomy, insertion of transgastric jejunal feeding tubes and biopsy. Less common salivary, hepatobiliary, pancreatic and intestinal interventions are also described.

Severe bronchomalacia treated by combination of Nuss procedure and aortopexy: an unusual therapy combination.

Aortopexy is the treatment of choice for clinically significant tracheobronchomalacia from external vascular compression. When a marked chest depression is present, aortopexy may be less effective. We report 2 patients with pectus excavatum and vascular compression of the trachea who, despite their young age, benefited from combined Nuss bar insertion and aortopexy.