Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

647 results found
Article

M-line of Cremin

M-line of Cremin is an imaginary line that can be used to determine the level at which the blind pouch ends in anal atresia, determining whether the anal atresia is a high or a low type. The line is drawn perpendicular to the long axis of the ischium on the lateral view and passes through the j...
Article

Macaroni sign

Macaroni sign is a sign seen in Takayasu arteritis on ultrasound. It represents smooth, homogeneous and moderately echogenic circumferential thickening of arterial wall that occurs in takayasu arteritis. The sign is highly specific for Takayasu arteritis, more commonly noted in the common caroti...
Article

Macdonald criteria for glioblastoma

Macdonald criteria, published in 1990 3, are used to assess response to first-line treatment of glioblastoma, but have been largely superseded by the RANO criteria which have become the mainstay of assessment.  For a general discussion see glioma treatment response assessment in clinical trials...
Article

MacEwen triangle

The MacEwen triangle (also called the suprameatal triangle or mastoid fossa) is a small triangular depression affecting the inner table of the temporal bone. The lines forming the triangle are: anterior: posterior border of the external acoustic meatus superior: posterior root of the zygomati...
Article

Mach bands

A mach band refers to an optical phenomenon from edge enhancement due to lateral inhibition of the retina 2. This has been attributed as a source of diagnostic error in radiology. An example is an appearance of a dark halo around a dense breast lesion in mammography 3. Another commonly encounted...
Article

Macro-nodular adrenal hyperplasia

Macro-nodular adrenal hyperplasia refers to a morphological type of adrenal hyperplasia in which there is adrenal enlargement in the form of large distinct nodules. It can be congenital or acquired. A specific subtype under this entity is adrenocorticotropin independent macronodular adrenocorti...
Article

Macrocephaly

Macrocephaly is a clinical and radiological term that refers to a generalised increase in size of the cranial vault. Terminology This slightly differs from the term megalencephaly which means an increase in size of the brain parenchyma.  Epidemiology content pending  Clinical presentation ...
Article

Macrocerebellum

Macrocerebellum, also known as cerebellar hyperplasia, refers to a rare condition characterised by an abnormally enlarged cerebellum with preserved architecture and shape. It is usually demonstrated on imaging with a thickening of the cortical gray matter of the cerebellar hemispheres. Epidemio...
Article

Macrocystic honeycombing

Macrocystic honeycombing refers to a morphological sub type of honeycombing. Many publications consider the insdividual lung cysts to be great than 4mm to be classified into this category.  This form is considered to be more associated with UIP 3. See also honeycombing microcystic honey...
Article

Macrodactyly

Macrodactyly in its broadest sense is a descriptive term which refers to enlargement of all the elements of a digit 1. This can mean either the hand or foot. Often it is equated with its most common cause, macrodystrophia lipomatosa 4. Rarely it can be seen as a form of Proteus syndrome 2 A num...
Article

Macrodystrophia lipomatosa

Macrodystrophia lipomatosa is a rare form of localised gigantism, and many terms have been used interchangeably, with resulting confusion. They include macrodactyly, megalodactyly, digital gigantism, macromelia, partial acromegaly, macrosomy, and limited gigantism 3. It is worth noting that  ma...
Article

Macroglossia

Macroglossia essentially means an enlarged tongue. It may be absolute (greater than the 95th centile) or relative (enlarged compared with oral cavity). Pathology Associations Recognised associations include: chromosomal anomalies Down syndrome tends to be a relative macroglossia may also ...
Article

Macrophthalmia

The increased globe size or macrophthalmia may have many differentials: buphthalmos (congenital glaucoma) axial myopia macrophthalmus in neurofibromatosis type 1 (NF1) connective tissue disorders: Marfan syndrome, Ehlers-Danlos syndrome Focal enlargement: staphyloma coloboma  
Article

Madelung deformity

Madelung deformity is due to defective development of ulnar third of the epiphysis of the distal radius, which results in a radial shaft that is bowed with an increased interosseous space, and dorsal subluxation of the distal radio-ulnar joint. It can be bilateral in 50-66% of patients. It ofte...
Article

Madelung deformity associations (mnemonic)

Mnemonics for remember the associations of Madelung deformity include: HITDOC Mnemonic HITDOC H: Hurler syndrome I: infection T: trauma D: dyschondrosteosis O: osteochondroma (multiple hereditary exostoses)  C: congenital, e.g. Turner syndrome
Article

Madelung disease

Madelung disease is a rare benign entity (lipomatosis) clinically characterised by the presence of multiple and symmetric, non-encapsulated masses of fatty tissue, usually involving the neck and the upper region of the trunk. It should not be confused with the Madelung deformity of the wrist.  ...
Article

Madelung dyschondrosteosis

Madelung dyschondrosteosis refers to a dysplasia associated with a Madelung deformity 1,2.  Pathology It is a form of mesomelic dwarfism, especially if the condition is bilateral or there is a family history of short stature. Associations Leri-Weill syndrome Radiographic features Has radio...
Article

Maduromycosis

Maduromycosis, also known as Maduramycosis or eumycetoma is caused by various fungi (e.g. madurella mycetomi) or actinomycetes (e.g. nocardia brasiliensis) which usually affects the feet. Pathology Initially a nodule, or abscess over months to years progresses to a chronic infection with the f...
Article

Maffucci syndrome

Maffucci syndrome is a congenital nonhereditary mesodermal dysplasia characterised by multiple enchondromas with soft-tissue venous malformations (haemangiomas). On imaging, it is usually portrayed by a short limb with metaphyseal distortions due to multiple enchondromas, which may appear grote...
Article

Magic angle effect - MRI artifact

The magic angle is an MRI artifact which occurs on sequences with a short TE (less than 32ms; T1W sequences, PD sequences and gradient echo sequences).  It is confined to regions of tightly bound collagen at 54.74° from the main magnetic field (B0), and appears hyperintense, thus potentially be...
Article

Magnetic resonance cholangiopancreatography

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique to visualize intra and extrahepatic biliary tree and pancreatic ductal system. It can provide the diagnostic range equivalent to the ERCP and so it can replace the ERCP in high risk patient to avoid significa...
Article

Magnetic resonance parkinsonism index

Magnetic resonance parkinsonism index (MRPI) can be used in MRI studies to predict the presence of progressive supranuclear palsy (PSP) in patients with clinically unclassifiable parkinsonism. MRPI is calculated by measuring the width of the superior cerebellar peduncle in the coronal plane, th...
Article

Magnetic susceptibility artifact

Magnetic susceptibility artifacts (or just susceptibility artifact) refer to a variety of MRI artifacts that share distortions or local signal change due to local magnetic field inhomogeneities from a variety of compounds.  They are especially encountered while imaging near metallic orthopedic ...
Article

Magnetism

Magnetism is a property of matter that is a result of the orbiting electrons in atoms. The orbiting electrons cause the atoms to have a magnetic moment associated with an intrinsic angular momentum called 'spin'.  Magnetic field strengths are measured in units of gauss (G) and Tesla (T). One Te...
Article

Magnets

Magnets used for MRI  are of three types: permanent, resistive and superconductive. Permanent MRI magnets use permanently magnetized iron like a large bar magnet that has been twisted into a "C" shape where the two poles are close together and parallel. In the space between the poles ...
Article

Magnification view

A magnification view is performed to evaluate and count microcalcifications and its extension (as well the assessment of the borders and the tissue structures of a suspicious area or a mass) by using a magnification device which brings the breast away from the film plate and closer to the x-ray ...
Article

MAGNIMS consensus on MRI diagnosis of multiple sclerosis

The magnetic resonance imaging in multiple sclerosis (MAGNIMS), which is a European collaborative research network, published in 2016 new recommendations to upgrade the imaging diagnosis criteria for multiple sclerosis (MS). These came as a consensus, based on evidence-based and expert opinions ...
Article

Maiden waist deformity

Maiden waist deformity is the appearance of the deviation of bilateral ureters. This typically occurs in retroperitoneal fibrosis. In this condition, there is medial drawing of the ureter due to deposition of fibrous tissue in the lumbosacral junction. Due to involvement of both ureters, the cou...
Article

Maisonneuve fracture

Maisonneuve fracture is the combination of a spiral fracture of the proximal fibula and unstable ankle injury which could manifest radiographically by widening of the ankle joint due to distal tibiofibular syndesmosis and/or deltoid ligament disruption, or fracture of the medial malleolus. It is...
Article

Major aortopulmonary collateral arteries

Major aortopulmonary collateral arteries (MAPCA's) are persistent tortuous fetal arteries that arise from the descending aorta and supply blood to pulmonary arteries in the lungs usually at the posterior aspect of hilum. Pathology Embryologically, the intersegmental arteries regress with the n...
Article

Major salivary glands

The major salivary glands are the largest and most important of the salivary glands and comprise of: paired parotid glands paired submandibular glands paired sublingual glands Related pathology salivary gland tumours
Article

Malacoplakia of the urinary tract

Malacoplakia of the urinary tract is an uncommon chronic granulomatous inflammatory disease of the bladder wall. Malakoplakia (meaning "soft plaque") can affect any organ, but the urinary bladder is the commonest location. Epidemiology Malacoplakia has a peak incidence in middle age,...
Article

Male breast cancer

Male breast cancer is exceptionally rare and only accounts for less than 0.25% of male malignancies and ~0.5-1% of all breast cancer (both genders). Epidemiology The average age of diagnosis of male breast cancer is 60-70 years, which is later than female breast cancer.  Clinical presentation...
Article

Male breast disease

Male breast disease includes a wide spectrum of conditions. Many conditions and entities that affect the female breast may also affect the male breast.  Pathology Malignant male breast cancer lymphoma dermatofibrosarcoma Benign gynaecomastia pseudogynaecomastia - fat deposition within th...
Article

Male pseudohermaphroditism

Male pseudohermaphroditism (MPH) is a variation of gender development.  Pathology Patients with male pseudohermaphroditism have 46 XY karyotype and may manifest as a female phenotype with various degrees of undervirilization secondary to partial androgen insensitivity.  Causes androgen insen...
Article

Male reproductive system

The male reproductive system (or tract) includes: penis testes epididymis vas deferens ejaculatory duct seminal vesicles and prostate It can be imaged using almost the entire range of imaging modalities but ultrasound and MRI are most often used (in part because these modalities are non-...
Article

Male urethra

The male urethra is a fibromuscular tube that drains urine from the bladder. It has a longer, more complicated, course than the female urethra and is also more prone to pathology. Gross anatomy The male urethra measures, on average, 18-20 cm in length. It commences at the internal urethral ori...
Article

Male urethral segments (mnemonic)

A helpful mnemonic to remember the 4 segments of the male urethra from proximal to distal. Pet My Big Penis P: prostatic M: membranous B: bulbous P: penile Posterior urethra includes the prostatic and membranous urethra.  Anterior urethra includes the bulbous and penile urethra. Related a...
Article

Malgaigne fracture

Malgaigne fracture is an unstable type of pelvic fracture, which involves one hemipelvis, and results from vertical shear energy vectors.  Clinical presentation One of the clinical features is shortening of the leg on the affected side. Pathology It comprises of two ipsilateral pelvic ring f...
Article

Malignant fibrous histiocytoma

Malignant fibrous histiocytomas (MFH), which has more recently being classified as pleomorphic undifferentiated sarcoma (PUS) and formerly known as fibrosarcoma, is considered the most common type of soft tissue sarcoma. It has an aggressive biological behaviour and a poor prognosis. Epidemiolo...
Article

Malignant liver tumours (paediatric)

Paediatric malignant liver tumours are rare, some of which occur only in children but that are similar to those that occur in adults. Epidemiology Malignant liver tumours account for ~1% of paediatric malignancies 2. Pathology Broadly, any malignant liver mass can be defined as a metastasis ...
Article

Malignant melanoma

Malignant melanoma is a malignant neoplasm that arises from melanocytes (or cells that derive from melanocytes).  Melanocytes predominantly occur in the basal layer of the epidermis and most melanomas therefore arise in the skin.  However, melanocytes do occur in other locations and can give ris...
Article

Malignant mixed germ cell tumour of the ovary

A malignant mixed germ cell tumour of the ovary is subtype of ovarian germ cell tumour. These are not to be confused with malignant mixed Müllerian tumours of the ovary. Epidemiology These tumours are rare. They most commonly affect adolescent women of reproductive age 1. Pathology They are ...
Article

Malignant mixed Mullerian tumour

Malignant mixed Mullerian is tumour (MMMT) (sometimes referred to as a carcinosarcoma) is a an uncommon malignancy that can occur anywhere along the female genital tract. Pathology It is comprised of both epithelial (carcinomatous) and stromal (sarcomatous) components. Implicated risk factors...
Article

Malignant mixed mullerian tumour of the uterus

Malignant mixed Mullerian tumour (MMMT) of the uterus, also known a uterine carcinosarcoma, is the commonest (up to 50%) of uterine sarcomas. They are thought to account for 2-8% of all malignant uterine cancers 1-2. The uterus is commonest site for malignant mixed Mullerian tumours 1.  Patholo...
Article

Malignant mixed tumours of salivary glands

Malignant mixed tumours of salivary glands, according to the WHO classification, comprise three tumours: carcinoma ex pleomorphic adenoma arises from pre-existing pleomorphic adenoma most common carcinosarcoma (true mixed tumour of the salivary glands) true malignant mixed tumour 99% also ...
Article

Malignant neoplasms involving the uterus

Malignant neoplasms involving the uterus account for a significant proportion of all female cancers. They can be classified as: endometrial carcinoma : commonest: >90% of all uterine malignancies endometrioid carcinoma of the uterus: commonest histological type, ~80% papillary serous carc...
Article

Malignant oesophageal neoplasms

Malignant oesophageal neoplasms are much more common than benign oesophageal neoplasms, especially if the patient is symptomatic.  Pathology oesophageal carcinoma (90%) oesophageal squamous cell carcinoma (SCC) oesophageal spindle cell carcinoma oesophageal adenocarcinoma oesophageal neuro...
Article

Malignant ovarian lesions: sonographic features

Malignant ovarian lesions can have typical sonographic features, and thus ultrasound is the imaging of choice for initial evaluation of suspected ovarian neoplasm. Radiographic features The features of malignant ovarian neoplasm on ultrasonography include: solid tumour mass >10 cm with lo...
Article

Malignant peripheral nerve sheath tumour

Malignant peripheral nerve sheath tumours (MPNSTs) are forms of peripheral nerve sheath tumours and comprise of malignant forms of neurofibromas and schwannomas.  Epidemiology They are estimated to account for 5-10% of all soft-tissue sarcomas. They typically present in adults. There is no rec...
Article

Malignant phyllodes tumour

Malignant phyllodes tumours of the breast account for a small proportion (5-25% 2) of phyllodes tumours. Pathology It is generally thought that it is the stromal component that becomes malignant 4. This may account for their haematogenous metastatic pattern. Radiographic features A substanti...
Article

Malignant pleural disease

Malignant pleural disease usually heralds a poor prognosis, whether it represents a primary pleural malignancy or metastatic involvement.  Clinical presentation Clinical presentation is variable. Patients may be asymptomatic or have pleuritic pain. If associated with a sizeable pleural effusio...
Article

Malignant rhabdoid tumour of the kidney

Rhabdoid tumour of the kidney is a rare, highly aggressive malignancy of early childhood, closely related to atypical teratoid/rhabdoid tumours (AT/RT) of the brain (see rhabdoid tumours) Epidemiology Rhabdoid tumours occur exclusively in children, with 60% occurring before the age of 1 year o...
Article

Malignant vascular tumours

Malignant vascular tumours rare, accounting for <1% of all sarcomas.  Pathology intermediate grade haemangioendothelioma Kaposi sarcoma high grade haemangiopericytoma angiosarcoma
Article

Malignant vs benign gastric ulcer (barium meal)

Barium meal has been frequently used to differentiate malignant and benign gastric ulcers. Features suggesting benign gastric ulcer outpouching of ulcer crater beyond the gastric contour (exoluminal) smooth rounded and deep ulcer crater smooth ulcer mound smooth gastric folds that reach the...
Article

Mallet finger

Mallet finger describes a type of injury where there is disruption of the extensor mechanism of the finger at the distal interphalangeal joint (DIP).It is the most prevalent finger tendon injury in sport. This can either refer to bony avulsion injury or just tendinous injury 5.  Clinical presen...
Article

Malleus

The malleus is the lateral most middle ear ossicle, located between the tympanic membrane and the incus. Gross anatomy The malleus has a head, neck, and three distinct processes (manubrium (handle), anterior and lateral processes). The head is oval in shape, and articulates posteriorly with t...
Article

Mallory bodies

Mallory bodies are cytoplasmic eosinophylic inclusions in hepatocytes, associated with ballooning and inflammation, found in: alcoholic fatty liver disease and hepatitis non-alcoholic fatty liver disease hepatocellular carcinoma (HCC) primary biliary cirrhosis (PBC) cholestasis
Article

Mallory Weiss tear

Mallory Weiss tears occur due to violent projection of gastric contents against the lower oesophagus, which results in mucosal and submucosal tear with involvement of the venous plexus.  Clinical presentation Patients present with massive painless haematemesis. Pathology Tears most commonly ...
Article

MALT lymphoma

Mucosa associated lymphoid tissue (MALT) lymphoma, also called extranodal marginal zone B-cell lymphoma, is a type of low-grade extranodal lymphoma.  Epidemiology MALT lymphoma represents ~7.5% of non-Hodgkin lymphomas. Average age of presentation is 60 years with a slight female predominance ...
Article

MALT lymphoma of the dura

MALT lymphoma of the dura (also known as primary dural lymphoma), a subset of primary leptomeningeal lymphoma, is rare, accounting for a very small proportion of CNS lymphoma and and even smaller proportion of dural masses. They are, unlike other CNS lymphomas, related to mucosa-associated lymp...
Article

Mamillopontine distance

Mamillopontine distance is defined as the distance between the inferior aspect of the mammillary bodies to superior aspect of the pons. In normal subjects, it should be >5.5 mm. It is decreased in conditions such as intracranial hypotension: it is one of the helpful quantitative signs helpf...
Article

Mammary duct ectasia

Mammary duct ectasia is characterised by chronic inflammatory and fibrotic changes leading to clogging of debris within the duct. It is of primary importance because of its features mimicking to that of malignancy. Terminology Some publications use this term synonymously with periductal mastit...
Article

Mammary fat

The mammary glands develop in close association with a depot of adipose tissue that is commonly referred to as the mammary fat pad.  The mammary fat pad is a matrix of adipose and connective tissue capable of mediating hormone action and synthesizing an array of growth regul...
Article

Mammillary bodies

The mammillary bodies form part of the hypothalamus and have a role in memory, although their exact role is yet to be established.  Gross anatomy The mammillary bodies are round,paired structures that are a relay in the Papez circuit and lie in the inferior hypothalamus. They are separated in ...
Article

Mammography

Mammography is a dedicated radiographic technique for imaging the breast. Types of mammography In general terms, there are two types of mammography: screening and diagnostic. Mammography differs significantly in many respects from the rest of diagnostic imaging. Screening mammography  In ge...
Article

Mammography views

There are numerous mammography views that can broadly be split into two groups standard views supplementary views - additional information or problem solving Standard views Standard views are those that are performed on routine screening mammograms. The views are usually used for all routine...
Article

Managing editor

Managing editors at Radiopaedia.org are part of the senior editorial team and have specific roles for development of the site and its content. As of 2016, there are three managing editors: Yuranga Weerakkody Henry Knipe Craig Hacking Responsibilities Between 2007 (launch) and 2014, Radiopa...
Article

Mandible

The mandible consists of a curved, horizontal portion, the body, and two perpendicular portions, the rami, which unite with the ends of the body nearly at right angles (angle of the jaw). It articulates with both temporal bones at the mandibular fossa at the temporomandibular joints (TMJ). Oste...
Article

Mandibular canal

Mandibular canal is located within the mandible and contains the inferior alveolar nerve, artery and the vein. It starts at the mandibular foramen, on the lingual side of the ramus, continues on buccal surface of body of the mandible and ends at the mental foramen, adjacent to the second premolar.
Article

Mandibular foramen

Mandibular foramen Is located on medial surface of ramus of the mandible. It transmits inferior alveolar nerve, a branch of mandibular division of the trigeminal nerve that supplies all teeth up till the midline.
Article

Mandibular fossa

The mandibular fossa is the smooth concave articular surface formed by both the squamous and petrous parts of the temporal bone. It is a part of temporomandibular joint and lodges the condyle of mandible.
Article

Mandibular fracture

Mandibular fractures are relatively common especially among young men. Although traditionally the mandible and base of skull are thought to form a complete bony ring, interrupted only by the TMJs. This should mean that the mandible should fracture in two places (akin to the bony pelvis) making s...
Article

Mandibular lesions

Mandibular lesions are myriad and common. The presence of teeth results in lesions that are specific to the mandible (and maxilla) and a useful classification that defines them as odontogenic or non-odontogenic. While it may often not be possible to make a diagnosis on imaging alone, this classi...
Article

Mandibular osteoradionecrosis

Mandibular osteoradionecrosis (ORN) is more common after radiation therapy for head and neck malignancies due to the superficial position of mandible, which makes it exposed to high radiation. The maxilla can also be involved, but this is less frequent.  Epidemiology Mandibular ORN may occur i...
Article

Mandibular periostitis

There are many causes for mandibular periostitis: Langerhans cell histiocytosis malignancy (both primary and metastatic) necrosis, e.g. radiation osteonecrosis osteomyelitis pyogenic Garre's sclerosing osteomyelitis actinomycosis (uncommon) syphilis (uncommon) tuberculosis (uncommon) r...
Article

Mandibular tori

Mandibular tori are common benign outgrowths of bone from the inner surface of the mandible.  They are composed of compact bone, densely mineralized usually without medullary cavity, and arise from the inner surface of the mandible above the origin of myolohyoid. They are usually bilateral. Se...
Article

Mannose-binding lectin deficiency

Mannose-binding lectin (MBL) deficiency is a condition that affects the immune system. Epidemiology It may be prevalent in 10-30% of the general population (dependant on the definition used). Pathology Affected individuals have low levels of an immune protein named mannose-binding lectin in ...
Article

Manta ray sign

The manta ray sign is a radiographic appearance in bladder exstrophy. It describes wide midline separation of the pubic bones simulating the appearance of a manta ray swimming towards you 1. Differential diagnosis On a plain radiograph consider: open book pelvic injuries: the smooth arc of th...
Article

Mantle cell lymphoma

Mantle cell lymphoma (MCL) is a type of non Hodgkin lymphoma (NHL) and accounts for ~5% of all NHL. It is a malignant neoplasm of virgin B cells that closely resemble normal mantle zone B cells surrounding germinal centres. Epidemiology They occur in older adults (mean age ~60 years). There is...
Article

Manubrium

The manubrium is the superior part of the sternum. It lies at the level of T3-T4 vertebrae. It forms the superior wall of the anterior mediastinum and its superior border also contributes to the superior thoracic aperture (thoracic inlet). The upper border of the manubrium also serves as the ape...
Article

Maple syrup urine disease

Maple syrup urine disease (MSUD) is a very rare metabolic disorder. It is an inborn error of amino acid metabolism, which classically affects the brain tissue resulting in impairment or death if untreated. Clinical presentation Manifests itself in the first few days of life (12-24 hours) with ...
Article

Maquet view

A maquet view is a type of radiographic projection of the lower limbs. They are a well established method of determining the axial alignment of the lower limb in the coronal plane and are of particular use in assessment of total knee replacements. Radiographic assessment Construct the weight ...
Article

Marbled pattern of the corpus callosum

Marbled pattern of the corpus callosum has been described in the acute phase of neuromyelitis optica (NMO) and represents multiple overlapping lesions with heterogeneous signal 1. This is distinct form the more typical appearance of multiple sclerosis (MS) where smaller separate individual lesio...
Article

Marburg's variant of multiple sclerosis

Marburg's variant of multiple sclerosis, also known as acute, fulminant, or malignant multiple sclerosis, is characterised by extensive and fulminant acute demyelination, often resulting in death within one year after the onset of clinical signs. Please, refer on multiple sclerosis (MS) for a b...
Article

March fracture

March fractures are a name subtype of fatigue/stress fracture. They occur due to repeated concentrated trauma to a normal bone, classically the 2nd metatarsal of the foot but can occur in other weight-bearing bones of the lower limb and pelvis. Radiographic features Please see the article on s...
Article

Marchiafava-Bignami disease

Marchiafava-Bignami disease (MBD) is a rare CNS disorder usually seen in the context of alcoholism and malnutrition. The condition classically involves the corpus callosum with necrosis and demyelination.  Epidemiology MBD is in most instances seen in chronic alcoholics, and as such the epidem...
Article

Marcus Gunn pupil

Marcus Gunn pupil, also known as afferent pupillary defect, is a nonspecific finding that indicates partial optic nerve dysfunction. It is mainly due to unilateral optic neuropathy, or rarely optic chiasm or optic tract lesions. In response to light input to the affected eye, both eyes do not c...
Article

Marfan syndrome

Marfan syndrome is a multisystem connective tissue disease with autosomal dominant inheritance of defect in fibrillin 1 gene with affected patients are tall with disproportionate long extremities and have pectus excavatum, arachnodactyly, and may also experience upward and lateral optic lens dis...
Article

Marginal artery of Drummond

The marginal artery of Drummond, also known as the marginal artery of the colon, is a continuous arterial circle or arcade along the inner border of the colon formed by the anastomoses of the terminal branches of the superior mesenteric artery (SMA) and inferior mesenteric artery (IMA). Gross a...
Article

Marginal artery of Drummond and arc of Riolan (mnemonic)

Remembering the colon vascular supply can be confusing because of inconstant collateral vascularisation. One way to remember the location of the marginal artery of Drummond is to remember that it runs distally to the root of the mesentery (near the colon). In comparison, although both originate...
Article

Marginal cord insertion

Marginal cord insertion is a type of abnormal cord insertion. Epidemiology The estimated incidence is at ~7% 1 of singleton pregnancies but ~25% of twin pregnancies. Hence, it is very important to locate the umbilical cord in all patients, particularly in high risk pregnancy. Pathology In th...
Article

Marginal placental abruption

Marginal placental abruption is the most common type of placental abruption wherein a haematoma is seen as the name suggests in the margin of the placenta and the blood collects below the chorionic membrane. It is most often seen in placentae that are partially implanted in the lower uterine seg...

Updating… Please wait.
Loadinganimation

Alert_accept

Error Unable to process the form. Check for errors and try again.

Alert_accept Thank you for updating your details.