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Wound Healing, Ulcers, and Scars
Published in Ayşe Serap Karadağ, Lawrence Charles Parish, Jordan V. Wang, Roxburgh's Common Skin Diseases, 2022
Saloni Shah, Christian Albornoz, Sherry Yang
Pathophysiology: The development of venous insufficiency begins with obstruction, valve incompetence, and/or elevated hydrostatic pressures within the calves. This results in venous hypertension and dilation of postcapillary venules, which compromises endothelial function. Venous insufficiency creates an environment for transudation, fibrin deposition in perivascular vessels, and extravasation of red blood cells causing hemosiderin deposition. Risk factors include the history of venous thrombosis, phlebitis, leg injury, congestive heart failure, pregnancy, prolonged standing, and varicose veins.
Atypical Teratoid / Rhabdoid Tumors – AT/RT
Published in David A. Walker, Giorgio Perilongo, Roger E. Taylor, Ian F. Pollack, Brain and Spinal Tumors of Childhood, 2020
Michael C. Frühwald, Jaclyn A. Biegel, Susan N. Chi
Warmuth-Metz et al. reported the results of computed tomography (CT) and magnetic resonance imaging (MRI) in a series of 33 consecutive AT/RT.59 They describe a distinct pattern of band-like enhancement surrounding a central hypointense tumor in 38% on contrast-enhanced images (Figure 17.3a). Jin and Feng list peripheral cysts, signs of hemorrhage, and hyperintense diffusion-weighted images as typical for AT/RT (Figure 17.3b, d).60 The solid parts of AT/RT are hypointense on T2 and severe restricted diffusion is observed on ADC (Figure 17.3a, b). The deposition of hemosiderin appears to be characteristic (Figure 17.3c). Commonly the borders of the lesion are surrounded by varying degrees of perifocal edema. The amount of edema may help in differentiating AT/RT from CNS PNET. Interestingly, a relatively high percentage of bone destruction in the vault or skull has been detected. In 91 consecutively imaged patients with AT/RT five revealed bone erosion.61 This is an unusual feature in other primary tumors of the CNS. AT/RT seem to be more often located in the cerebellopontine angle,62 but often extend beyond anatomical borders (Figure 17.3a).
Cellular Components of Blood
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
Hb contains 65%–70% of the total body iron, with myoglobin containing 4%–5%. Iron is also associated with cellular respiration through the action of iron-containing enzymes such as cytochromes, catalase and peroxidase. Iron is transported in plasma by transferrin, a β1-globulin that binds two atoms of ferric iron per molecule. The main source of iron carried by transferrin is from the reticuloendothelial cells that destroy ageing red cells. Some iron is also stored in the reticuloendothelial cells as haemosiderin and ferritin. Ferritin is a water-soluble protein–iron complex consisting of an outer protein shell, called apoferritin, and an inner core of iron–phosphate–hydroxide complex.
Diagnostic value of MRI in coexistence of schwannoma and meningioma mimicking a single dumbbell-shaped tumor in high cervical level. Case series and literature review
Published in The Journal of Spinal Cord Medicine, 2023
Guang Bin Zheng, Zhenghua Hong, Zhangfu Wang
The extradural tumor presented proliferation of spindle-shaped cells with fascicular or palisading arrangement in hematoxylin and eosin (H&E) staining. Hemosiderin deposits were occasionally observed. Immunohistochemically, these extradural tumors were positive for S-100 protein and negative for epithelial membrane antigen (EMA). For intradural masses, proliferation of oval-shaped or spindle-shaped cells with scattered psammoma bodies was observed in H&E staining. Immunohistochemical results showed the tumor cells were positive for EMA and negative for S-100 protein. These findings confirmed the diagnosis of concurrent arising of extradural schwannomas and intradural meningiomas in the same cervical level (Fig. 4). All of the intradural meningiomas were grade I according to the World Health Organization (WHO) classification.
Histotyping and grading of endometriosis and its association with clinico-pathological parameters
Published in Journal of Obstetrics and Gynaecology, 2022
Jyothika Litson, Rini Agnes, Gayatri Ravikumar
The histopathological features studied include the quantity of endometriotic foci, components, phasing of the endometriotic foci, and stromal features.Quantity of endometriotic foci (severity): Assessed on the entire tissue examined and graded based on the extent occupied in low power field (LP) as (i) mild (one LP field), (ii) moderate (2–3 LP fields) and (iii) severe (>3 LP fields).The components in the endometriotic foci: classified as (i) pure glandular (when only glands were present without stroma), (ii) pure stromal (only stroma was present without glands), and (iii) mixed stromal and glandular (both gland and stroma were present). The type of gland seen was also classified as endometrial type (well-differentiated glands), undifferentiated type (when glandular component resembled other mesothelial types), and glandular pattern of mixed differentiation (both endometrial and undifferentiated glands present). The presence and absence of haemorrhage and hemosiderin was recorded.Phasing of the endometriotic foci: inactive, proliferative, or secretory, similar to that of eutopic endometrium. The presence of atypia was noted.Stromal features: Presence of oedema, fibrosis, and inflammation was noted.
Optic Neuropathy Revealing Severe Superficial Siderosis in the Setting of Long-standing Low-grade Intracranial Neoplasm
Published in Neuro-Ophthalmology, 2022
Coralie Hemptinne, Adrienne Coche, Thierry Duprez, Philippe Demaerel, Christian Raftopoulos, Antonella Boschi
Once visual symptoms have appeared, no currently available treatment can reverse tissue damage due to haemosiderin deposits. Various chelating agents, targeting either iron (e.g., desferrioxamine), or iron and copper (e.g., trientine), have been used in observational reports with little clinical improvement.13 Furthermore, no significant results have been reported to date in a larger number of patients. As SS is a progressive disease that can irreversibly lead to dementia and death, the goal of its treatment should be to prevent haemosiderin deposition by curatively treating the cause of the chronic subarachnoid bleeding.1,6 Therefore, haemosiderin-sensitive sequences including GRE T2- and even T1-weighted ones (T1* and T2*) and/or the so-called ‘SWI using the blood oxygen level dependent’ (SWI-BOLD) should be requested for an early identification of haemosiderin deposit in the anterior visual pathway.