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Medulloepithelioma
Medulloepithelioma is a rare, primitive, fast-growing brain tumour thought to stem from cells of the embryonic medullary cavity.Definition of Medulloepithelioma , from Online Medical Dictionary. Retrieved 7 January 2010. Tumours originating in the of the are referred to as embryonal medulloepitheliomas, or diktyomas.McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diktyoma
Diktyoma, or ciliary body medulloepithelioma, or teratoneuroma, is a rare tumor arising from primitive medullary epithelium in the ciliary body of the eye. Almost all diktyomas arise in the ciliary body, although, rarely, they may arise from the optic nerve head or retina. The name "diktyoma" comes from its characteristic findings on histology. Signs and Symptoms The most common symptoms of diktyoma are vision loss and pain, while the most common signs are leukocoria and presence of a mass in the iris or ciliary body.McLeanIW, Burnier MN, Zimmerman LE, Jakobiec FA. Tumors of the retina. In: Rosai J, Sobin LH, eds. Atlas of tumor pathology: tumors of the eye and ocular adnexa. Washington, DC: Armed Forces Institute of Pathology, 1994; 101–135. Other signs and symptoms include lens subluxation, glaucoma, cataract, exophthalmos, buphthalmos, strabismus, and ptosis. Diagnosis Classification Diktyoma is classified into teratoid and nonteratoid types, based on heteroplastic tissue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Tumour
A brain tumor (sometimes referred to as brain cancer) occurs when a group of cells within the brain turn cancerous and grow out of control, creating a mass. There are two main types of tumors: malignant (cancerous) tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and secondary tumors, which most commonly have spread from tumors located outside the brain, known as brain metastasis tumors. All types of brain tumors may produce symptoms that vary depending on the size of the tumor and the part of the brain that is involved. Where symptoms exist, they may include headaches, seizures, problems with vision, vomiting and mental changes. Other symptoms may include difficulty walking, speaking, with sensations, or unconsciousness. The cause of most brain tumors is unknown, though up to 4% of brain cancers may be caused by CT scan radiation. Uncommon risk factors include exposure to vinyl chloride, Epstein–Bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurosurgery
Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the specialty (medicine), medical specialty that focuses on the surgical treatment or rehabilitation of disorders which affect any portion of the nervous system including the Human brain, brain, spinal cord, peripheral nervous system, and cerebrovascular system. Neurosurgery as a medical specialty also includes non-surgical management of some neurological conditions. Education and context In different countries, there are different requirements for an individual to legally practice neurosurgery, and there are varying methods through which they must be educated. In most countries, neurosurgeon training requires a minimum period of seven years after graduating from medical school. United Kingdom In the United Kingdom, students must gain entry into medical school. The MBBS qualification (Bachelor of Medicine, Bachelor of Surgery) takes four to six years depending on the student's route. The newly qu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or even larger. In humans, the cerebellum plays an important role in motor control and cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in fine motor skill, fine movement, sense of balance, equilibrium, list of human positions, posture, and motor learning in humans. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunohistochemistry
Immunohistochemistry is a form of immunostaining. It involves the process of selectively identifying antigens in cells and tissue, by exploiting the principle of Antibody, antibodies binding specifically to antigens in biological tissues. Albert Coons, Albert Hewett Coons, Ernst Berliner, Ernest Berliner, Norman Jones and Hugh J Creech was the first to develop immunofluorescence in 1941. This led to the later development of immunohistochemistry. Immunohistochemical staining is widely used in the diagnosis of abnormal cells such as those found in cancerous tumors. In some cancer cells certain tumor antigens are expressed which make it possible to detect. Immunohistochemistry is also widely used in basic research, to understand the distribution and localization of biomarkers and differentially expressed proteins in different parts of a biological tissue. Sample preparation Immunohistochemistry can be performed on tissue that has been fixed and embedded in Paraffin wax, paraffin, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flexner-Wintersteiner Rosette
In histopathology, a palisade is a single layer of relatively long cells, arranged loosely perpendicular to a surface and parallel to each other. A rosette is a palisade in a halo or spoke-and-wheel arrangement, surrounding a central core or hub. A pseudorosette is a perivascular radial arrangement of neoplastic cells around a small blood vessel. Rosettes are characteristic of tumors. Rosette A ''rosette'' is a cell formation in a halo or spoke-and-wheel arrangement, surrounding a central core or hub. The central hub may consist of an empty-appearing lumen or a space filled with cytoplasmic processes. The cytoplasm of each of the cells in the rosette is often wedge-shaped with the apex directed toward the central core: the nuclei of the cells participating in the rosette are peripherally positioned and form a ring or halo around the hub. Pathogenesis Rosettes may be considered primary or secondary manifestations of tumor architecture. Primary rosettes form as a characteristic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Needle Aspiration Biopsy
Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin (23–25 gauge (0.52 to 0.64 mm outer diameter)), hollow needle is inserted into the mass for sampling of cells that, after being stained, are examined under a microscope (biopsy). The sampling and biopsy considered together are called fine-needle aspiration biopsy (FNAB) or fine-needle aspiration cytology (FNAC) (the latter to emphasize that any aspiration biopsy involves cytopathology, not histopathology). Fine-needle aspiration biopsies are very safe for minor surgical procedures. Often, a major surgical (excisional or open) biopsy can be avoided by performing a needle aspiration biopsy instead, eliminating the need for hospitalization. In 1981, the first fine-needle aspiration biopsy in the United States was done at Maimonides Medical Center. The modern procedure is widely used to diagnose cancer and inflammatory conditions. Fine needle aspiration i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcification
Calcification is the accumulation of calcium salts in a body tissue. It normally occurs in the formation of bone, but calcium can be deposited abnormally in soft tissue,Miller, J. D. Cardiovascular calcification: Orbicular origins. ''Nature Materials'' 12, 476-478 (2013). causing it to harden. Calcifications may be classified on whether there is mineral balance or not, and the location of the calcification. Calcification may also refer to the processes of normal mineral deposition in biological systems, such as the formation of stromatolites or mollusc shells (see Biomineralization). Signs and symptoms Calcification can manifest itself in many ways in the body depending on the location. In the pulpal structure of a tooth, calcification often presents asymptomatically, and is diagnosed as an incidental finding during radiographic interpretation. Individual teeth with calcified pulp will typically respond negatively to vitality testing; teeth with calcified pulp often lack ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Diagnosis
Medical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as a diagnosis with the medical context being implicit. The information required for a diagnosis is typically collected from a history and physical examination of the person seeking medical care. Often, one or more diagnostic procedures, such as medical tests, are also done during the process. Sometimes the posthumous diagnosis is considered a kind of medical diagnosis. Diagnosis is often challenging because many signs and symptoms are nonspecific. For example, redness of the skin ( erythema), by itself, is a sign of many disorders and thus does not tell the healthcare professional what is wrong. Thus differential diagnosis, in which several possible explanations are compared and contrasted, must be performed. This involves the correlation of various pieces of information followed by the recognition and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to form images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from computed tomography (CT) and positron emission tomography (PET) scans. MRI is a medical application of nuclear magnetic resonance (NMR) which can also be used for imaging in other NMR applications, such as NMR spectroscopy. MRI is widely used in hospitals and clinics for medical diagnosis, staging and follow-up of disease. Compared to CT, MRI provides better contrast in images of soft tissues, e.g. in the brain or abdomen. However, it may be perceived as less comfortable by patients, due to the usually longer and louder measurements with the subject in a long, confining tube, although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computerized Tomography
A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or radiology technologists. CT scanners use a rotating X-ray tube and a row of detectors placed in a gantry (medical), gantry to measure X-ray Attenuation#Radiography, attenuations by different tissues inside the body. The multiple X-ray measurements taken from different angles are then processed on a computer using tomographic reconstruction algorithms to produce Tomography, tomographic (cross-sectional) images (virtual "slices") of a body. CT scans can be used in patients with metallic implants or pacemakers, for whom magnetic resonance imaging (MRI) is Contraindication, contraindicated. Since its development in the 1970s, CT scanning has proven to be a versatile imaging technique. While CT is most prominently used in medical diagnosis, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
