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Fracture healing

Fracture healing occurs naturally after traumatic bony disruption. This process begins with hemorrhage and progresses through three stages: inflammatory reparative remodeling This process can be supported by various treatment options with immobilization a mainstay; inappropriate treatment ma...

CA 19-9

CA 19-9 (carbohydrate antigen 19-9 or cancer antigen 19-9) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-maligna...

WHO histological classification of tumors of the uterine cervix

The WHO histological classification is a detailed classification of tumors of the uterine cervix. epithelial tumors squamous tumors and precursors squamous cell carcinoma, not otherwise specified - 8070/3 keratinizing - 8071/3 non-keratinizing - 8072/3 basaloid - 8083/3 verrucous - 8051/3...

Inflammation

Inflammation is a response to a noxious stimuli which can be either be acute or chronic. The cardinal signs of inflammation include: heat (calor) redness (rubor) swelling (tumor) pain (dolor) loss of tissue function (functio laesa) Subtypes Acute Inflammation Acute inflammation occurs w...

Adenoma-carcinoma sequence

The adenoma-carcinoma sequence refers to a stepwise pattern of mutational activation of oncogenes (e.g. K-ras) and inactivation of tumor suppressor genes (e.g. p53) that results in cancer. An oncogene is a gene that has the potential to cause cancer. In tumor cells, these are often mutated or ex...

Columnar alteration with prominent apical snouts and secretions

Columnar alteration with prominent apical snouts and secretions (CAPSS) is a pathological entity encountered when breast biopsies are done for investigation of punctate or amorphous calcifications. CAPSS involves the terminal ductal and lobular units (TDLU's). It is sometimes classified under t...

Atresia

Atresia (plural: atresias) refers to a situation where there is absence, underdevelopment or abnormal closure, of a normal anatomical tubular structure or opening. Contrast this with agenesis which refers to the complete absence of any anatomical structure including its primordial precursors. ...

Mesenchyme

Mesenchyme, or mesenchymal connective tissue, is a type of undifferentiated connective tissue. It is predominantly derived from the embryonic mesoderm, although may be derived from other germ layers, e.g. mesenchyme derived from neural crest cells (ectoderm). The term mesenchyme is often used t...

CA-125

CA-125 is a high-molecular-weight glycoprotein found on the surface of Müllerian and celomic epithelial-derived cell types and is the best known tumor marker for epithelial ovarian cancer 6. Importantly, it may also be elevated in several other conditions (see differential diagnosis section belo...

Haggitt level

The Haggitt level is a histopathological term used for describing the degree of infiltration from a malignant polypoidal lesion. Levels of invasion 0: carcinoma in situ or intramucosal carcinoma 1: invasion of the submucosa, but limited to the head of the polyp 2: invasion extending into the...

Aspergillus clavatus

Aspergillus clavatus is one of the species of Aspergillus that can cause pathology in humans. It is allergenic and causes a hypersensitivity pneumonitis called malt-workers lung. See also Aspergillus Aspergillus fumigatus Aspergillus flavus Aspergillus clavatus

Neuritic plaques

Neuritic plaques (also known as senile plaques) are pathological extracellular aggregates formed around a core of amyloid β peptide and are a hallmark of Alzheimer disease. They should not be confused with neurofibrillary tangles which are intracytoplasmic. Pathology Neuritic plaques are ext...

Myo-inositol peak

Myo-inositol is one of the compounds images with MR spectroscopy (MRS) at both 1.5 T and 3 T and is seen to resonate at 3.5 ppm chemical shift (right of the choline peak). Myo-inositol is a precursor of both phosphatidylinositol (the major inositol-containing phospholipid) and phosphatidylinos...

Pick bodies

Pick bodies are intracytoplasmic spherical inclusions found in Pick disease. They are composed of tau fibrils (thus Pick disease is a tauopathy) arranged in a disorderly array 1. Although tau protein is a major component a number of other protein products are present, including ubiquitin and tub...

Neurofibrillary tangles

Neurofibrillary tangles (NFTs) are abnormal cytoplasmic accumulations of tau proteins, found in neuronal and glial cells of the central nervous system. They are responsible for a number of neurodegenerative diseases (collectively known as tauopathies) including 1: progressive supranuclear palsy...

Rosenthal fibers

Rosenthal fibers are astrocytic cytoplasmic inclusions, typically found in areas of longstanding gliosis. These elongated or "corkscrew" structures occur within astrocytic processes and are brightly eosinophilic (stain bright pink on the H&E stain) 1-3. They represent astrocytic processes swolle...

Langerhans cell

Langerhans cells are dendritic cells of monocyte-macrophage lineage, containing large granules called Birbeck granules. They are normally found in epithelial surfaces, lymph nodes and other organs, and can also be found elsewhere, particularly in association with Langerhans cell histiocytosis. ...

Polyostotic

Polyostotic, less commonly polystotic, is a term used to describe a condition involving multiple bones. Examples of conditions that can be polyostotic include Paget disease of the bone, fibrous dysplasia and melorheostosis. See also monostotic monomelic

Monomelic

Monomelic is typically used to refer to a condition that is confined to only one limb. Examples of conditions that can be monomelic include fibrous dysplasia and melorheostosis. See also monostotic polyostotic monomelic

Monostotic

Monostotic is typically used to refer to a condition that involves only one bone. Examples of conditions that can be monostotic include fibrous dysplasia and melorheostosis. See also polyostotic monomelic

Charcot-Leyden crystals

Charcot-Leyden crystals consist of collections of bipyramidal crystalloid made up of eosinophilic membrane proteins, which occur in: asthma other eosinophilic lung disease 2 certain cases of sinusitis (e.g. allergic fungal sinusitis) They may be detected in the sputum or sinus secretions wi...

Hepatoblastoma histological classification

Although hepatoblastomas can be histologically classified into a variety of subtypes, it is important to remember that with the possible exception of small cell undifferentiated subtype, prognosis is independent of histology when adjusted for stage gender and age 1. major categories epithelial...

Cyst

A cyst is an abnormal fluid-filled structure which is lined by epithelium; with one exception: lung cysts may contain gas or fluid. By contradistinction, a pseudocyst lacks an epithelial lining and instead has a vascular and fibrotic capsule. Cysts are extremely common and found in most organs....

Pseudocyst

A pseudocyst is an abnormal fluid-filled cavity which is not lined by epithelium. It is this fact that distinguishes it pathologically from a cyst, which is lined by epithelium. Examples of pseudocysts include: adrenal pseudocyst auricular pseudocyst intraspinal epidural gas pseudocysts me...

Diverticulum

Diverticula are outpouchings of a hollow viscus and can be either true or false. Occasionally a diverticulum is used in a more general sense to mean the outpouching of other anatomical structures, e.g. frontal intersinus septal cells are hypothesized to form as diverticula from the frontal sinu...

Histology of blood vessels

Blood vessels, namely arteries and veins, are composed of endothelial cells, smooth muscle cells and extracellular matrix (including collagen and elastin). These are arranged into three concentric layers (or tunicae): intima, media and adventitia. the intima (or tunica intima) inner layer abut...

Intracranial arteries

Intracranial arteries have a unique structure when compared to extracranial vessels of similar size: see general histology of blood vessels entry. Proximal larger arteries The proximal arteries, arising from the internal carotid and vertebral arteries have differing distribution of elastic fib...

Vitamin A

Vitamin A are a group of fat-soluble vitamers (the retinoids) required for many physiological functions, mainly vision, reproduction and epithelial maintenance. In the retina, a specific retinoid, 11-cis-retinal, is formed by photoisomerisation within the rods and cones. The retinoids are hemati...

Psammoma bodies

Psammoma bodies are round microscopic calcific collections. It is a form of dystrophic calcification. Necrotic cells form the focus for surrounding calcific deposition. They have a lamellated concentric calcified structure, sometimes large enough to be seen on CT. Psammoma bodies are found in ...

Cowdry bodies

Cowdry bodies are eosinophilic or basophilic neuronal intranuclear inclusions composed of nucleic acid and protein, this cytopathic changes are considered a hallmark of viral infection.1. Pathology Cowdry bodies are in fact fixation artifacts and not directly the result of the intracellular vi...

Choristoma

A choristoma is simply a collection of microscopically normal cells or tissues in an abnormal location. This is different to a hamartoma which is derived only from local tissues. Examples include: adrenal choristoma (myelolipoma) nasopharyngeal choristoma facial nerve choristoma optic nerve...

Aneurysm

Aneurysms are focal abnormal dilatation of a blood vessel. They typically occur in arteries; venous aneurysms are rare. Aneurysms may also occur in the heart. Pathology Pathological types true aneurysm false aneurysm (or pseudoaneurysm) Etiology Atherosclerotic atherosclerosis Non-athero...

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