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Structural Methods in the Study of Development of the Lung
Published in Joan Gil, Models of Lung Disease, 2020
Paul Davies, Daphne deMello, Lynne M. Reid
Lung weight and volume are often expressed relative to body weight to give the “specific value.” Indeed, hypoplasia is best detected in this way, by lower than normal specific values. Morphometric and stereological estimates can be expressed similarly.
Hemolytic Anemia Associated with Red Cell Membrane Defects
Published in Harold R. Schumacher, William A. Rock, Sanford A. Stass, Handbook of Hematologic Pathology, 2019
Bone marrow biopsy is not routinely indicated in PNH patients. When serious cytopenias are present, bone marrow examination may provide useful information. Usually, erythroid hyperplasia is present in PNH patients. Varying degrees of hypoplasia may also be seen.
Respiratory Medicine
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
Colin Wallis, Helen Spencer, Sam Sonnappa
In unilateral pulmonary aplasia, it is common to find either a rudimentary bronchus that ends blindly (Fig. 4.31) or enters a very underdeveloped and non-functioning lung. If some functioning lung is present the term hypoplasia is used. Anomolous venous drainage can be associated with left-sided congenital hypoplasia (see scimitar syndrome below). The unaffected lung or lobes can function normally apart from the compensatory overinflation to fill the empty hemithorax.
Ocular manifestations of systemic diseases in children
Published in Clinical and Experimental Optometry, 2023
Cheefoong Chong, Ann L Webber, Shuan Dai
Children with optic nerve hypoplasia often have nystagmus, with levels of visual impairment varying from near normal to perception of light. Classically, the hypoplastic nerve is described as exhibiting a ‘double-ring sign’. However, the degree of hypoplasia is highly variable in severity, ranging from unilateral, mildly hypoplastic nerves, to complete agenesis. A more reliable method for its diagnosis is based on fundus photography, measuring the ratio between disc diameter to disc-macula distance. A ratio of <3 is highly specific for optic nerve hypoplasia32 (Figure 6). From an eye care perspective, all children with optic nerve hypoplasia will require regular review to ensure their refractive error is optimally corrected and low vision aids offered.
Hypoplastic left heart syndrome (HLHS): molecular pathogenesis and emerging drug targets for cardiac repair and regeneration
Published in Expert Opinion on Therapeutic Targets, 2021
Anthony T Bejjani, Neil Wary, Mingxia Gu
HLHS can be caused by several defects in the left heart, but the most common results from mitral valve stenosis and obstruction of flow into and/or out of the left ventricle, ultimately leading to a hypoplastic left ventricle [13]. In cases where the aortic valve is defective, increased afterload in the left ventricle leads to the dilation of the ventricle and decreased contractility. As a result, diminished blood flow results in hypoplasia of the left ventricle during fetal development [14]. Additionally, increased pressure in the left atrium can lead to the reversal of blood flow into the right atrium through the foramen ovale and into the right ventricle, which can become hypertrophic [15]. The resulting decrease in left ventricular pressure triggers hypoplasia of the left heart. Alternatively, mitral valve atresia or stenosis can lead to decreased preload in the left ventricle, causing hypoplasia [14].
Minimal invasive vertical muscle transposition for the treatment of large angle exotropia due to congenital medial rectus hypoplasia: Case Report and Literature Review
Published in Strabismus, 2020
Mohammad Yaser Kiarudi, Aliakbar Sabermoghadam, Mahsa Sardabi, Seyed Vahid Jafarzadeh, Mohammad Etezad Razavi
For the management of strabismus, different transposition methods have been used. In previous studies, the most common procedure was full/half tendon transposition of the vertical rectus muscles to the site of medial rectus insertion with or without myopexy suture (Table 1). In minimal invasive method originally described by Nishida,5 the vector of vertical rectus muscles is brought to the palsied muscle without tenotomy. With this technique, the transposed muscle bellies generate adductional force at the suturing point. In our report, a large-angle exotropia corrected to less than 10 PD exotropia in primary position. In addition, the patient gained some degrees of adduction. We previously corrected large-angle esotropia due to complete sixth nerve palsy by this procedure.4 Sharma et al.13 also applied a modification of this technique in a case of MR hypoplasia.