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Nasopharyngeal Angiofibroma
Nasopharyngeal angiofibroma is an angiofibroma also known as juvenile nasal angiofibroma, fibromatous hamartoma, and angiofibromatous hamartoma of the nasal cavity. It is a histologically benign but locally aggressive vascular tumor of the nasopharynx that arises from the superior margin of the sphenopalatine foramen and grows in the back of the nasal cavity. It most commonly affects adolescent males (because it is a hormone-sensitive tumor). Though it is a benign tumor, it is locally invasive and can invade the nose, cheek, orbit (frog face deformity), or brain. Patients with nasopharyngeal angiofibroma usually present with one-sided nasal obstruction with profuse epistaxis. Signs and symptoms * Frequent chronic epistaxis or blood-tinged nasal discharge * Nasal obstruction and rhinorrhea * Facial dysmorphism (when locally invasive) * Conductive hearing loss from eustachian-tube obstruction * Diplopia, which occurs secondary to erosion into superior orbital fissure and due to third ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrograph
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs. A micrograph contains extensive details of microstructure. A wealth of information can be obtained from a simple micrograph like behavior of the material under different conditions, the phases found in the system, failure analysis, grain size estimation, elemental analysis and so on. Micrographs are widely used in all fields of microscopy. Types Photomicrograph A light micrograph or photomicrograph is a micrograph prepared using an optical microscope, a process referred to as ''photomicroscopy''. At a basic level, photomicroscopy may be performed simply by connecting a camera to a microscope, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyogenic Granuloma
A pyogenic granuloma or lobular capillary hemangioma is a vascular tumor that occurs on both mucosa and skin, and appears as an overgrowth of tissue due to irritation, physical trauma, or hormonal factors. It is often found to involve the gums, skin, or nasal septum, and has also been found far from the head, such as in the thigh. Pyogenic granulomas may be seen at any age, and are more common in females than males. In pregnant women, lesions may occur in the first trimester with an increasing incidence until the seventh month, and are often seen on the gums. Signs and symptoms The appearance of pyogenic granuloma is usually a color ranging from red/pink to purple, grows rapidly, and can be smooth or mushroom-shaped. Younger lesions are more likely to be red because of their high number of blood vessels. Older lesions begin to change into a pink color. Size commonly ranges from a few millimeters to centimeters, though smaller or larger lesions may occur. A pyogenic granuloma can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasopharyngeal Cyst
Nasopharyngeal cyst refers to cystic swelling arising from midline and lateral wall of the nasopharynx. The commonest cyst arising from lateral wall is the nasopharyngeal branchial cyst, whereas the mucus retention cysts are the commonest to arise from the midline. Sometimes nasopharyngeal cyst may directly refer to Tornwaldt cyst. It arises from the midline and lies deep to the pharyngobasilar fascia which helps to distinguish it from a mucous retention cyst. The main difference lies in that nasopharyngeal branchial cyst is congenital whereas the Tornwaldt's cyst is acquired. Nasopharyngeal Branchial Cyst These are congenital cysts often arising from the fossa of Rosenmüller located in the lateral wall of the nasopharynx. They represent remnants of first branchial cleft. These may extend superiorly to reach the bony confines of eustachian tube even to the skull base. Initially patients are asymptomatic but may present with aural fullness, unilateral conductive hearing loss, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordoma
Chordoma is a rare slow-growing neoplasm thought to arise from cellular remnants of the notochord. The evidence for this is the location of the tumors (along the neuraxis), the similar immunohistochemical staining patterns, and the demonstration that notochordal cells are preferentially left behind in the clivus and sacrococcygeal regions when the remainder of the notochord regresses during fetal life. In layman's terms, chordoma is a type of spinal cancer. Presentation Chordomas can arise from bone in the skull base and anywhere along the spine. The two most common locations are cranially at the clivus and in the sacrum at the bottom of the spine. Sacral chordoma is presented with chronic low back pain. Genetics A small number of families have been reported in which multiple relatives have been affected by chordoma. In four of these families, duplication of the brachyury gene was found to be responsible for causing chordoma. A possible association with tuberous sclerosi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhabdomyosarcoma
Rhabdomyosarcoma (RMS) is a highly aggressive form of cancer that develops from mesenchymal cells that have failed to fully differentiate into myocytes of skeletal muscle. Cells of the tumor are identified as rhabdomyoblasts. There are four subtypes – embryonal rhabdomyosarcoma, alveolar rhabdomyosarcoma, pleomorphic rhabdomyosarcoma, and spindle cell/sclerosing rhabdomyosarcoma. Embryonal, and alveolar are the main groups, and these types are the most common soft tissue sarcomas of childhood and adolescence. The pleomorphic type is usually found in adults. It is generally considered to be a disease of childhood, as the vast majority of cases occur in those below the age of 18. It is commonly described as one of the small-blue-round-cell tumors of childhood due to its appearance on an H&E stain. Despite being relatively rare, it accounts for approximately 40% of all recorded soft tissue sarcomas. RMS can occur in any soft tissue site in the body, but is primarily found in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmacytoma
Plasmacytoma is a plasma cell dyscrasia in which a plasma cell tumour grows within soft tissue or within the axial skeleton. The International Myeloma Working Group lists three types: solitary plasmacytoma of bone (SPB); extramedullary plasmacytoma (EP), and multiple plasmacytomas that are either primary or recurrent. The most common of these is SPB, accounting for 3–5% of all plasma cell malignancies. SPBs occur as lytic lesions within the axial skeleton and extramedullary plasmacytomas most often occur in the upper respiratory tract (85%), but can occur in any soft tissue. Approximately half of all cases produce paraproteinemia. SPBs and extramedullary plasmacytomas are mostly treated with radiotherapy, but surgery is used in some cases of extramedullary plasmacytoma. The skeletal forms frequently progress to multiple myeloma over the course of 2–4 years. Due to their cellular similarity, plasmacytomas have to be differentiated from multiple myeloma. For SPB and extramedu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphoma
Lymphoma is a group of blood and lymph tumors that develop from lymphocytes (a type of white blood cell). In current usage the name usually refers to just the cancerous versions rather than all such tumours. Signs and symptoms may include enlarged lymph nodes, fever, drenching sweats, unintended weight loss, itching, and constantly feeling tired. The enlarged lymph nodes are usually painless. The sweats are most common at night. Many subtypes of lymphomas are known. The two main categories of lymphomas are the non-Hodgkin lymphoma (NHL) (90% of cases) and Hodgkin lymphoma (HL) (10%). The World Health Organization (WHO) includes two other categories as types of lymphoma – multiple myeloma and immunoproliferative diseases. Lymphomas and leukemias are a part of the broader group of tumors of the hematopoietic and lymphoid tissues. Risk factors for Hodgkin lymphoma include infection with Epstein–Barr virus and a history of the disease in the family. Risk factors for common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasopharyngeal Carcinoma
Nasopharyngeal carcinoma (NPC), or nasopharynx cancer, is the most common cancer originating in the nasopharynx, most commonly in the postero-lateral nasopharynx or pharyngeal recess ( fossa of Rosenmüller), accounting for 50% of cases. NPC occurs in children and adults. NPC differs significantly from other cancers of the head and neck in its occurrence, causes, clinical behavior, and treatment. It is vastly more common in certain regions of East Asia and Africa than elsewhere, with viral, dietary and genetic factors implicated in its causation. It is most common in males. It is a squamous cell carcinoma of an undifferentiated type. Squamous epithelial cells are a flat type of cell found in the skin and the membranes that line some body cavities. ''Undifferentiated cells'' are cells that do not have their mature features or functions. Signs and symptoms NPC may present as a lump or a mass on both sides towards the back of the neck. These lumps usually are not tender or pain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malignancy
Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not self-limited in its growth, is capable of invading into adjacent tissues, and may be capable of spreading to distant tissues. A benign tumor has none of those properties. Malignancy in cancers is characterized by anaplasia, invasiveness, and metastasis. Malignant tumors are also characterized by genome instability, so that cancers, as assessed by whole genome sequencing, frequently have between 10,000 and 100,000 mutations in their entire genomes. Cancers usually show tumour heterogeneity, containing multiple subclones. They also frequently have reduced expression of DNA repair enzymes due to epigenetic methylation of DNA repair genes or altered microRNAs that control DNA repair gene expression. Tumours can be detected through the visual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhinosporidiosis
Rhinosporidiosis is an infection caused by ''Rhinosporidium seeberi''. Classification This organism was previously considered to be a fungus, and rhinosporidiosis is classified as a fungal disease under ICD-10. It is now considered to be a protist classified under Mesomycetozoea. Authors of detailed studies have revealed superficial similarities between ''Dermocystidium'' and '' Rhinosporidium'' when using light microscopy, but substantial morphological differences between the groups exist. There is some evidence that DNA extracted from purified uncontaminated round bodies (Rhinosporidium seeberi) is of cyanobacterial origin. Pathophysiology Rhinosporidiosis is a granulomatous disease affecting the mucous membrane of nasopharynx, oropharynx, conjunctiva, rectum and external genitalia. Though the floor of the nose and inferior turbinate are the most common sites, the lesions may appear elsewhere too. Traumatic inoculation from one site to others is common. Laryngeal rhinosporidio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from CT and 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, though "Open" MRI designs mostly relieve this. Additionally, implants and oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
