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Giant Cell Tumor Of Bone
Giant-cell tumor of the bone (GCTOB) is a relatively uncommon bone tumor characterized by the presence of multinucleated giant cells (osteoclast-like cells). Malignancy in giant-cell tumor is uncommon and occurs in about 2% of all cases. However, if malignant degeneration does occur, it is likely to metastasize to the lungs. Giant-cell tumors are normally benign, with unpredictable behavior. It is a heterogeneous tumor composed of different cell populations. The giant-cell tumour stromal cells (GCTSC) constitute the neoplastic cells, which are from a mesenchymal stem cell origin and are classified based on expression of osteoblast cell markers such as alkaline phosphatase and osteocalcin. In contrast, the mononuclear osteoclast precursor cells giving rise to multinucleated giant cells (MNGC) are secondarily recruited and comprise the non-neoplastic cell population. They are derived from an hematopoietic monocyte/ macrophage lineage determined primarily by expression of ''CD68' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrograph
A micrograph is an image, captured photographically or digitally, taken through a microscope or similar device to show a magnify, 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 photographic micrograph is a photomicrograph, and one taken with an electron microscope is an electron micrograph. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Cell Tumour Of Bone - Very High Mag
In folklore, giants (from Ancient Greek: ''gigas'', cognate giga-) are beings of humanoid appearance, but are at times prodigious in size and strength or bear an otherwise notable appearance. The word ''giant'' is first attested in 1297 from Robert of Gloucester's chronicle. It is derived from the ''Gigantes'' () of Greek mythology. Fairy tales such as ''Jack the Giant Killer'' have formed the modern perception of giants as dimwitted and violent ogres, sometimes said to eat humans, while other giants tend to eat livestock. In more recent portrayals, like those of Jonathan Swift and Roald Dahl, some giants are both intelligent and friendly. Literary and cultural analysis Giants appear many times in folklore and myths. Representing the human body enlarged to the point of being monstrous, giants evoke terror and remind humans of their body's frailty and mortality. They are often portrayed as monsters and antagonists, but there are exceptions. Some giants intermingle with human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteoblastoma
Osteoblastoma is an uncommon osteoid tissue-forming primary neoplasm of the bone. It has clinical and histologic manifestations similar to those of osteoid osteoma; therefore, some consider the two tumors to be variants of the same disease, with osteoblastoma representing a giant osteoid osteoma. However, an aggressive type of osteoblastoma has been recognized, making the relationship less clear. Although similar to osteoid osteoma, osteoblastoma is larger (between 2 and 6 cm). Signs and symptoms Patients with osteoblastoma usually present with pain of several months' duration. In contrast to the pain associated with osteoid osteoma, the pain of osteoblastoma usually is less intense, usually not worse at night, and not relieved readily with salicylatesfluid ( aspirin and related compounds). If the lesion is superficial, the patient may have localized swelling and tenderness. Spinal lesions can cause painful scoliosis, although this is less common with osteoblastoma tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteoid Osteoma
An osteoid osteoma is a benign (non-cancerous) bone tumor that arises from osteoblasts and some components of osteoclasts. It was originally thought to be a smaller version of an osteoblastoma. Osteoid osteomas tend to be less than 1.5 cm in size. The tumor can be in any bone in the body but are most common in long bones, such as the femur and tibia. They account for 10 to 12 percent of all benign bone tumors and 2 to 3 percent of all abnormal bone growths. Osteoid osteomas may occur at any age, and are most common in patients between the ages of 4 and 25 years old. Males are affected approximately three times more commonly than females. Osteoid osteomas are different than osteomas, which are rather found in older patients and localized in the skull. Signs and symptoms Common symptoms of an osteoid osteoma are: * dull or sharp pain that worsens at night * pain that is usually relieved by aspirin or other anti-inflammatory drugs * limping * painful scoliosis and muscle spa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Cyst
A bone cyst or geode is a cyst that forms in bone. Types include: * Unicameral bone cyst (simple or solidary bone cyst) * Aneurysmal bone cyst * Traumatic bone cyst Diagnosis On CT scans, bone cysts that have a radiodensity of 20 Hounsfield units (HU) or less, and are osteolytic, tend to be aneurysmal bone cysts. In contrast, intraosseous lipomas have a lower radiodensity of -40 to -60 HU. Treatment and Prevention Simple (Unicameral) Bone Cyst Some unicameral bone cysts may spontaneously resolve without medical intervention. Specific treatments are determined based on the size of the cyst, the strength of the bone, medical history, extent of the disease, activity level, symptoms an individual is experiencing, and tolerance for specific medications, procedures, or therapies. The types of methods used to treat this type of cyst are curettage and bone grafting, aspiration, steroid injections, and bone marrow injections. Watchful waiting and activity modifications are the mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondroblastoma
Chondroblastoma is a rare, benign, locally aggressive bone tumor that typically affects the epiphyses or apophyses of long bones. It is thought to arise from an outgrowth of immature cartilage cells ( chondroblasts) from secondary ossification centers, originating from the epiphyseal plate or some remnant of it. Chondroblastoma is very uncommon, accounting less than 1% of all bone tumors. (The chances of having this condition are roughly one in a million.) It affects mostly children and young adults with most patients being less than 20 years of age. Chondroblastoma shows a predilection towards the male sex, with a ratio of male to female patients of 2:1. The most commonly affected site is the femur, followed by the humerus and tibia. Less commonly affected sites include the talus and calcaneus of the foot and flat bones. Signs and symptoms The most common symptom is mild to severe pain that is gradually progressive in the affected region and may be initially attributed to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRI Contrast Agent
MRI contrast agents are contrast agents used to improve the visibility of internal body structures in magnetic resonance imaging (MRI). The most commonly used compounds for contrast enhancement are gadolinium-based contrast agents (GBCAs). Such MRI contrast agents shorten the Relaxation (NMR), relaxation times of nuclei within body tissues following oral or intravenous administration. Due to safety concerns, these products carry a Boxed warning, Black Box Warning in the USA. Theory of operation In MRI scanners, sections of the body are exposed to a strong magnetic field causing primarily the hydrogen nuclei ("spins") of water in tissues to be polarized in the direction of the magnetic field. An intense radiofrequency pulse is applied that tips the magnetization generated by the hydrogen nuclei in the direction of the receiver coil where the spin polarization can be detected. Random molecular rotational oscillations matching the resonance frequency of the nuclear spins provide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRI Sequence
An MRI pulse sequence in magnetic resonance imaging (MRI) is a particular setting of pulse sequences and pulsed field gradients, resulting in a particular image appearance. A multiparametric MRI is a combination of two or more sequences, and/or including Magnetic resonance imaging#Other specialized configurations, other specialized MRI configurations such as In vivo magnetic resonance spectroscopy, spectroscopy. Spin echo T1 and T2 Each tissue returns to its equilibrium state after excitation by the independent relaxation processes of T1 (Spin–lattice relaxation, spin-lattice; that is, magnetization in the same direction as the static magnetic field) and T2 (Spin-spin relaxation time, spin-spin; transverse to the static magnetic field). To create a T1-weighted image, magnetization is allowed to recover before measuring the MR signal by changing the repetition time (TR). This image weighting is useful for assessing the cerebral cortex, identifying fatty tissue, characteriz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medullary Cavity
The medullary cavity (''medulla'', innermost part) is the central cavity of bone shafts where red bone marrow and/or yellow bone marrow (adipose tissue) is stored; hence, the medullary cavity is also known as the marrow cavity. Located in the main shaft of a long bone (diaphysis) (consisting mostly of spongy bone), the medullary cavity has walls composed of compact bone (cancellous bone) and is lined with a thin, vascular membrane (endosteum). This area is involved in the formation of red blood cells and white blood cells, and the calcium supply for bird eggshells. The area has been detected in fossil bones despite the fossilization process. Intramedullary is a medical term meaning the inside of a bone. Examples include intramedullary rods used to treat bone fractures in orthopedic surgery and intramedullary tumors occurring in some forms of cancer or benign tumors such as an enchondroma Enchondroma is a type of benign bone tumor belonging to the group of cartilage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generalized Signal Averaging
Within signal processing, in many cases only one image with noise is available, and averaging is then realized in a local neighborhood. Results are acceptable if the noise is smaller in size than the smallest objects of interest in the image, but blurring of edges is a serious disadvantage. In the case of smoothing within a single image, one has to assume that there are no changes in the gray levels of the underlying image data. This assumption is clearly violated at locations of image edges, and edge blurring is a direct consequence of violating the assumption. Description Averaging is a special case of discrete convolution. For a 3 by 3 neighborhood, the convolution mask ''M'' is: M = \frac \begin1 & 1 & 1 \\ 1 & 1 & 1 \\ 1 & 1 & 1 \\ \end The significance of the central pixel may be increased, as it approximates the properties of noise with a Gaussian Carl Friedrich Gauss (1777–1855) is the eponym of all of the topics listed below. There are over 100 topics all name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voxel
In computing, a voxel is a representation of a value on a three-dimensional regular grid, akin to the two-dimensional pixel. Voxels are frequently used in the Data visualization, visualization and analysis of medical imaging, medical and scientific data (e.g. geographic information systems (GIS)). Voxels also have technical and artistic applications in video games, largely originating with surface rendering in ''Outcast (video game), Outcast'' (1999). ''Minecraft'' (2011) makes use of an entirely voxelated world to allow for a fully destructable and constructable environment. Voxel art, of the sort used in ''Minecraft'' and elsewhere, is a style and format of 3D art analogous to pixel art. As with pixels in a 2D bitmap, voxels themselves do not typically have their position (i.e. coordinates) explicitly encoded with their values. Instead, Rendering (computer graphics), rendering systems infer the position of a voxel based upon its position relative to other voxels (i.e., its pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aneurysmal Bone Cyst
Aneurysmal bone cyst (ABC) is a non-cancerous bone tumor composed of multiple varying sizes of spaces in a bone which are filled with blood. The term is a misnomer, as the lesion is neither an aneurysm nor a cyst. It generally presents with pain and swelling in the affected bone. Pressure on neighbouring tissues may cause compression effects such as neurological symptoms. The cause is unknown. Diagnosis involves medical imaging. CT scan and X-ray show lytic expansion lesions with clear borders. MRI reveals fluid levels. Treatment is usually by curettage, bone grafting or surgically removing the part of bone. 20–30% may recur, usually in the first couple of years after treatment, particularly in children. It is rare. The incidence is around 0.15 cases per one million per year. Aneurysmal bone cyst was first described by Jaffe and Lichtenstein in 1942. Signs and symptoms The afflicted may have relatively small amounts of pain that will quickly increase in severity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
