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Introduction to: Problem Oriented Approach in Pediatric Radiology Introduction Pediatric Radiology is the application of diagnostic radiology in the understanding ,diagnosis, therapy, and follow up of diseases of infants and children. To minimize radiation risks and maximize benefits from any imaging examination ,the procedure should be tailored to the specific clinical problem. An algorithm for each clinical presentation , will help to reach a “definite “ diagnosis ,with the least radiation exposure and cost . The referring physician ,as well as the pediatric Radiologist ,have the duty to take PROBLEM ORIENTED DECISIONS ,which will decide ,which techniques will be used or omitted in any given clinical situation ,so as to reach the appropriate diagnosis. I-Thorax CXR-showing a large mediastinal mass lesion . 1. Patient with a chest mass. The clinical problem : The discovery of a chest mass on CXR is a common finding which can happen in the course of investigation for a tachypneic child ,signs of SVC obstruction ,coughing ,chest infection ,or incidentally. The need for identifying a normal thymus is needed. The location of chest mass is necessary to build a working differential diagnosis. Role of Radiology: An approach includind CXR with chest US has been proposed by some authors . The technique depends on examining the chest through suprasternal ,parasternal and sub-xiphoid windows. The main role of U.S. is : 1. Identify a normal thymus.

Problem oriented approach in pediatric radiology

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This hand book tries to address the most common clinical problems in pediatrics ,by building a problem based imaging algorithm ,which probes the different differential diagnosis and try to reach a final diagnosis.

Text of Problem oriented approach in pediatric radiology

  • 1. Introduction to: Problem Oriented Approach inPediatric RadiologyIntroductionPediatric Radiology is the application of diagnostic radiology in the understanding ,diagnosis, therapy, andfollow up of diseases of infants and children.To minimize radiation risks and maximize benefits from any imaging examination ,the procedure should betailored to the specific clinical problem.An algorithm for each clinical presentation , will help to reach a definite diagnosis ,with the least radiationexposure and cost .The referring physician ,as well as the pediatric Radiologist ,have the duty to take PROBLEM ORIENTEDDECISIONS ,which will decide ,which techniques will be used or omitted in any given clinical situation ,so asto reach the appropriate diagnosis. I-ThoraxCXR-showing a large mediastinal mass lesion . 1. Patient with a chest mass.The clinical problem :The discovery of a chest mass on CXR is a common finding which can happen in the course ofinvestigation for a tachypneic child ,signs of SVC obstruction ,coughing ,chest infection ,or incidentally.The need for identifying a normal thymus is needed.The location of chest mass is necessary to build a working differential diagnosis.Role of Radiology:An approach includind CXR with chest US has been proposed by some authors .The technique depends on examining the chest through suprasternal ,parasternal and sub-xiphoidwindows.The main role of U.S. is :1. Identify a normal thymus.

2. 2. Differentiate between a cystic or solid mass lesions.3. Study of the cystic lesion which is most likely bening-regarding its size ,wall ,contents ,etc..Etiology Anterior MediastinumMiddle Mediastinum Posterior MediastinumCongenital Thymic cyst Foregut cyst Foregut cyst. Morgagni Hernia Hiatal hernia-achalasiaLateral meningoceleBochdaleck HerniaInflammatory Mediastinitis.Mediastinitis. +spinal inflammatory Lymohadenopathy LymphadenopathydiseasesNeoplastic Lymphoma-Leukemia Lymphoma-LeukemiaNeurogenic Germ Cell tumor. tumours(neural crest or Teratoma peripheral nerveTumors ).lymphoma-Leukemia-Phaechromocytoma.TraumaticHaematoma Hematoma.Spinal fracture Thymic Hemorrhage Diaphragmatic ruptureVascular Annomalous vessel Aneurysm.Aortic aneurysm Great vessels anomalyDilated azygous veinMiscelaneous Histiocytosis Pancreatic pseudocyst- Extramedullary Sarcoidosis Histiocytosis-sarcoidosisHaematopoiesis.4. Evaluate the solid lesion regarding its site ,size ,borders ,presence or absence of necrosis ,vascularity ,etc..5. guide for interventional procedure (biopsy or aspiration for peripheral lesion Etiology:I-Mediastinal masses.II-Chest wall masses:-Normal structures at pleural surfaceLocation CausesSoft tissue tumors Lymphangioma Cystic HygromaExtrapleural intrathoracicMesenchymoma-Lipoma RhabdomyosarcomaBony thorax tumors Generalized bone diseases :Neurofibromatosis-Multiple hereditary exostosis, Benign causes:fibrous dysplasia-osteochondroma-eosinophilic granuloma- Aneurysmal bone cyst. Malignant:Ewing Sarcoma- PNET-chondrosarcoma-Osteosarcoma 3. Metastatic: Neuroblastoma-LeukemiaIII-Lung Masses :LocationCausesPleural Metastasis-Leukemia-Lymphoma-Askin tumorPrimary:Parenchymal Benign:Bronchogenic cyst-Sequestration-Roundpneumonia-hamartoma-bronchial adenoma.Malignant:Sarcoma-Pulmonary BlastomaSecondary:Benign:PapillomatosisMalignant:Wilmstumor,Osteosarcoma,etc.B-Flow of thinking : 5 questions to ask.1.Location 2.Density 3.enhancement 4.Morphology 5. Associations(Wall/med/lung) (air/fat/calcification) ( border/size/shape) (displacement/bony Destruction) 4. 2. Patient with upper Airway Obstruction CXR:Church steeple sign denoting CroupA-Etiology :The differential diagnosis of upper air way obstruction depends upon :the age of presentation (neonatal?older children),associated findings (fever/nasal obstruction/stridor),history of foreign body inhalation.MechanismCauses Choanal atresia -micrognathia-ectopic thyroid-laryngomalacia-laryngeal ,subglottic trachealCongenital stenosis-nasal encephalocele. Adenoids- retropharyngeal abscess-croup-epiglottitis-Inflammatory Laryngeal,aryepiglottic,retention,or epiglottic cysts-cystic hygroma-hemangioma-papilloma- Rhabdomyosarcoma-dermoid / teratoma-Nasopharyngeal mass(Angiofibroma)Masses Foreign body-hematoam-radiation-thrermal injury.Traumatic Tracheomalacia-vascular ring-angioneurotic edemaMiscellaneousRole of Imaging:1.Croup:Pathophysiology: The cells of the respiratory epithelium are infected following viral inhalation. Inflammation isdiffuse in the involved airway.X-ray diagnosis: Frontal neck radiograph: The lateral walls of the subglottic larynx normally are convex orshouldered . Wall edema in croup narrows this space with loss of lateral convexity, creating a steeple shapebelow the vocal cords The narrowing may extend for 5-10 mm below the vocal cords.2.Epiglottitis:Pathophysiology: Epiglottitis causes inflammation and swelling of the epiglottis, vallecula, arytenoids, andaryepiglottic folds. As the tissues swell, they protrude downward and over the glottic opening, making breathingdifficult. 5. X-ray diagnosis: In epiglottitis, images show diffuse soft-tissue swelling with enlargement of the epiglottis and also ofthe normally thin aryepiglottic folds. One should look for an enlarged epiglottis (thumbprint sign), thickenedaryepiglottic folds, and ballooning of the hypopharynx, usually with normal subglottic structures .CXR:Bilateral consolidation patches-Broncho-pneumonia3. Patient with chest InfectionA-Etiology : 1. Viral(Adeno virus-Haemophylis Influenza Respiratory syncitial virus) 2. Bacterial (streptococcal-Staphylococcal-Klebsiella) 3. Fungal(aspergillosis) 4. Tuberculous. 5. Mycoplasma. 6. Amebic.B-Complications: 1. Empyema. 2. Pulmonary abscess. 3. Bronchopleural fistula. 4. Septic embolization. 6. Large pleural collection in left hemithorax post staph pneumonia-Empyema. Ultrasonic examination revealing loculated pleural effusion.4. Patient with recurrent/chronic pulmonary problemsA-Etiology :Extensive list for the causes of chronic /recurrent lung infections are present.Mechanism CausesCNS malformation-cerebral tumors-1. Aspiration Tracheo-esophageal fistula-RefluxCongenital lobar emphysema-2.Anomaly Sequestration-Tracheobronchial treeanomalies(tracheal bronchus-stenosis-atresia)-bronchogenic cyst.Astham- Loeffler pneumonia-allergic3.Allergy.alveolitisCystic fibrosis4.Systemic disease.Prematurity-AIDS-Neutropenia5.Immunodeficiency.Foreign body-Drugs-radiation-6.Physical agents.Bronchopulmonary dysplasia 7. Leukemia-Lymphoma-Histiocytosis7.Neoplasm. Left to right shunt -PA stenosis-8.CVSvascular ring TB-Mycoplasma-Bronchiectasis9.specific Infections. Interstitial Pneumonia-Collagen10.Miscellaneous vascular disease-Alveolar proteinosis-sarcoidosis.B-Role of Radiology :The role of radiology is 3 folds :1 .Evaluate the present X-ray. Look for : The presence and distribution of opacities,Pleural involvement ,Lymph nodal swellings ,pulmonaryvascularity ,soft tissue involvement , bony structures .2.Review of previous films.Look for:Are the lesion stable in the same location (Sequestration ?)Are they present always in upper lobe (aspiration ? )Are they changing in location (Immunodeficiency ?)3.Perform esophagogram.Look for :1. Reflux of gastric contents.2. Abnormal peristalsis-Compression of esophagus by a mass ,vascular ring.3. Tracheo-esophageal fistula.4. Hiatal Hernia 8. Left basal pulmonary lesion with systemic aterial supply (2)..Pulmonary sequestration5.Neonate with respiratory distressCXR :RDS Bilateral Opacification with air bronchogram.Etiology:1.Respiratory distress syndrome.2.Congenital Diaphragmatic Hernia. 9. 3. Congenital Cystic Adenomatoid Malformation. 4. Congenital Lobar Emphysema. 5. Lung agenesis /hypoplasia. 6. Tracheal stenosis/atresia. 7. Pulmonary sling. 8. Vascular ring.Role of imaging1.Congenital Cystic adenomatoid Malformation:Pathogenesis and pathophysiologic features: CAM is believed to result from focal arrest in fetal lung developmentbefore the seventh week of gestation secondary to a variety of pulmonary insults.Types:Type I lesions, the most common, are composed of 1 or more cysts measuring 2-10 cm in diameter.Type II lesions are characterized by small relatively uniform cysts resembling bronchiolesType III lesions consist of microscopic, adenomatoid cysts, and are grossly a solid mass without obvious cystformation.Radiographic findings:The pattern in the lung demonstrates multiple radiolucent areas that vary greatly in size and shape. Cysts are separatedfrom each other by strands of opaque pulmonary tissue.The involved lung may appear honeycombed or spongy, but occasionally, 1 large cyst may overshadow the others. Airtrapping within cystic spaces can cause rapid enlargement of the CAMCT findings:Areas of small cysts (2 cm in diameter) are seen alone or with other abnormalities (areas of small cysts,consolidation, or low attenuation).Low-attenuation areas are clusters of microcysts.Air-fluid levels can be seen in some cysts. These lesions may be predominantly type I, type II, or a combination ofboth. 10. MRI findings:In CAM, prenatal MRI findings on T2-weighted images have been reported. CAMs appear asintrapulmonary masses with increased signal intensity on T2-weighted images. Type III CAM lesions have moderatelyhigh signal intensity.Ultrasonic diagnosis:Partially cystic partially echogenic masses are characteristic of type I or type II lesions. The size or dimension of thecysts distinguishes the 2 types. Type III lesions may be large and entirely echogenic.Chest X-ray revealing multiple basal lung cysts (CCAM)CT chest :right basal cystic lesions-CCAM2.Congenital lobar emphysema:Pathophysiology: Overdistension of the airspaces within a pulmonary lobe is associated with air trapping andcompressive changes in the remainder of the lung . Mediastinal shift away from the increased volume results incompression of the contralateral lung. CLE almost always involves one lobe, with rates of occurrence as follows:Left upper lobe - 41%Right middle lobe - 34%Right upper lobe - 21%X-ray findings: A large, hyperlucent lung with attenuated but defined vascularity is observed. Compressed remaininglung on that side, flattened hemidiaphragm, and widened intercostal spaces also are seen. An involved lung is seenherniated across the anterior midline.On a lateral view, the heart is displaced posteriorly with retrosternal lucencyrepresenting an anteriorly herniated lobe . 11. CXR:large right basal cystic lesion. CT rvealed area of hyperlucency :Congental Lobar EmphysemaCT findings: CT scan shows a hyperlucent, hyperexpanded lobe (attenuated but intact pattern of organized vascularity)with midline substernal lobar herniation and compression of the remaining lung. Usually, the mediastinum issignificantly shifted away from the side of the abnormal lobe .3.Respiratory distress syndrome :Pathophysiology: RDS is the result of anatomic pulmonary immaturity and a deficiency of surfactant. Pulmonarysurfactant synthesis, in type II pneumocytes, begins at 24-28 weeks of gestation, and gradually increases until fullgestation. Pulmonary surfactant decreases surface tension in the alveolus during expiration, allowing the alveolus toremain partly expanded, thereby maintaining a functional residual capacity.In premature infants, an absence of surfactant results in poor pulmonary compliance, atelectasis, decreased gasexchange, and severe hypoxia and acidosis.X-ray diagnosis:The radiologic spectrum of RDS ranges from mild to severe and is generally correlated with the severity of the clinicalfindings.In the early stages of the disease, notable air bronchograms are lacking because the major bronchi lie in themore anterior portions of the lungs and because alveolar atelectasis tends to involve the dependent areas of the lungs,which are posterior in recumbent infants. However, a bubble appearance, which represents overdistended bronchiolesand alveolar ducts, can be observed. As RDS progresses, the reticulogranular pattern becomes prominent due tocoalescence of the small atelectatic areas. This coalescence leads to larger areas of increased lung opacity. As theanterior portions of the lung become involved with microatelectasis, the granularity becomes uniformly distributed, andair bronchograms can be seen. With increasing severity of disease, progressive opacification of the anterior portions ofthe lungs cause obscuration of cardiac silhouette and the formation of prominent air bronchograms. With severedisease, the lungs appear opaque and display prominent air bronchograms, with total obscuration of cardiomediastinalsilhouette. 12. CXR :respiratory distress syndromeComplications:1.Pulmonary interstitial emphysema:PIE can be symmetrical, asymmetrical, or localized to 1 portion of a lung. Peripheral PIE can producesubpleural blebs and ultimately rupture into pleural space to produce pneumothorax (usually tensionpneumothorax), or they can extend centrally to produce pneumomediastinum or pneumopericardium.Because infants are supine and because air rises to the highest point of the thorax, the pneumothorax islocated paramediastinally, resulting in the sharp mediastinum sign, whereby the mediastinum/heart issharply outlined by adjacent free air rather than aerated lung tissue.CXR :Pulmonary interstitial emphysema2.Bronchopulmonary dysplasia:After days of ventilatory support, interstitial fibrosis results from the cumulative effect of therapeutic insult tothe pulmonary parenchyma. This fibrosis is often accompanied by exudative necrosis and a honeycombappearance of the lungs on chest radiography. The honeycomb appearance represents focally distendedalveolar groups in a scarred, and immature lungs. 13. CT chest : ARDS in NICU patient with difficult extubation II Body1. Vomiting Digestive origin Extra digestive originFrequentRareInfectious Otitis media - Labyrinthitis-Pneumonia-UTICongenitalMicrogastriaNeurological Cerebralhypertophic Pylorictumors,hydrocephalus,Abscess,hematomastenosisAntral Dyskinesia Antral DiaphragmToxicLead poisoning-Chemotherapy-Vitamin A&D poisoningIntussusception.Midgut volvulus MetabolicFructosemia-Galactosemia-Tyrosinemia- Adrenal insufficiencyHirschprung disease Preduodenal portalPsychicAnorexiaveinGastroenteritis Ladds BandAcute AppendicitisGastric or duodenalUlcer1.Congenital Hypertrophic Pyloric stenosis:Pathophysiology: Full-thickness biopsies demonstrate both hypertrophy and hyperplasia of the circular muscle layer ofthe pylorus.Sex: Male-to-female ratio is 4-6:1.Age: HPS most commonly is seen in infants aged 3-6 weeksImaging:1. Ultrasonic diagnosis ;US examination showing CHPS: note thich muscular layer and elongated canal 14. Target sign on transverse images of the pylorusMuscle thickness of >3mmPyloric channel length greater than 17 mmPyloric thickness (serosa to serosa) of 15 mm or greaterFailure of the channel to open during a minimum of 15 minutes of scanningRetrograde or hyperperistaltic contractionsAntral nipple sign, a prolapse of redundant mucosa into the antrum (creating a pseudomass)2.Intussusception:Role of imaging :Abdominal radiograph:Look for dilated small bowel and absence of gas in the region of the cecum . Occasionally, a massimpression within the colonic gas indicates an intraluminal mass created by the intussuscepting loop.Abdominal radiograph :intususception transverse colonUltrasoundTransverse: Ultrasound (US) shows a mass with a swirled appearance of alternating sonolucent and hyperechoic bowelwall of the loop-within-a-loop.Longitudinal: US of the mass shows a submarine sandwich-like appearance of the intussuscipiens and theintussusceptum. There appear to be multiple layers, which represent the walls of the intussuscepted bowel loops . 15. Ultrasonic examination showing Donut sign of intususception3.Mid gut Volvulus:Malrotation is caused by incomplete rotation (