Articles

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More than 200 results
Article

Rectal prolapse

A rectal prolapse is a form of pelvic organ prolapse and refers to the prolapse of the rectum into the anal canal. They can involve the entire wall of the rectum or only the mucosal layer. Epidemiology Rectal prolapse in Western populations is more common in females (M:F 1:4). In women, it is ...
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Lumbar epidural gas

Lumbar epidural gas is a rare phenomenon where gas locules are observed within the spinal canal of the lumbar spine. It can arise from a number of factors: due to regional degenerative disc disease with or without dorsal epidural disc migration: thought to be from gas leaking from the disc spac...
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CNS embryonal tumor with PLAGL amplification

CNS embryonal tumor with PLAGL amplification is a recently identified pediatric brain tumor found in both the supratentorial and infratentorial brain defined by amplification of the PLAGL1 or PLAGL2 genes. Given its histological overlap with other embryonal CNS tumors, it was previously misclass...
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Indirect inguinal hernia

Indirect inguinal hernias (alternative plural: herniae), a type of groin herniation, are the most common type of abdominal hernia. Epidemiology It is five times more common than a direct inguinal hernia, and is seven times more frequent in males, due to the persistence of the processus vaginal...
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Anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) reconstruction is a common procedure post ACL tear. It 's aim is to rebuild the anatomy and function of the native ACL and reduce knee joint instability, thus it will prevent any further meniscal and/or cartilage damage.  Procedure There are numerous surgical t...
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Emphysematous cystitis

Emphysematous cystitis refers to a gas-forming infection of the bladder wall. Epidemiology The condition is rare and usually confined to certain patient subgroups. Median age affected is 66 years. More common in women, 2:1 F:M 9. Risk factors Risk factors include: diabetes mellitus conside...
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Pelvic organ prolapse

Pelvic organ prolapse refers to a pathological downward herniation of various pelvic organ structures into or through the perineum. It usually results from pelvic floor weakness by impairment of various ligaments, fasciae, and muscles that support the pelvic organs. In its most severe form, it ...
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Shading sign (endometrioma)

Shading sign is an MRI finding typically seen in an endometrioma. It may also be seen with some endometrioid tumors (e.g. endometrioid carcinoma of the ovary) and uncommonly other blood-containing lesions (e.g. hemorrhagic corpus luteum cysts). The sign describes lesions that are hyperintense o...
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T2 dark spot sign (endometrioma)

T2 dark spot sign is an MRI appearance of endometriomas as a result of chronic hemorrhage. The sign is useful in differentiating a solitary endometrioma from a functional hemorrhagic ovarian cyst, as both might show high T1 signal with T2 shading.  The sign describes a focal T2 hypointense nodu...
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Mushroom cap sign (endometriosis)

The mushroom cap sign is one of the important signs of deep rectosigmoid endometriosis on T2-weighted MRI sequences. It is highly specific for submucosal involvement of the rectosigmoid colon and can be useful for differentiating endometriosis from other infiltrating lesions, such as malignancie...
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Obturator externus muscle

The obturator externus is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis. Summary Origin: external surface of obturator membrane and adjacent bone (inferior pubic ramus and the ramus of the ischium) Insertion: trochanteric fossa of femur Blood su...
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Mesothelioma

Mesothelioma is an aggressive malignant tumor of mesothelium and 90% of tumors arise from the pleura. This article is about the pleural form of the disease, other locations include 17: peritoneal mesothelioma (~10%) pericardial mesothelioma (<1%) cystic/multicystic mesothelioma tunica vagi...
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Cryptogenic organizing pneumonia

Cryptogenic organizing pneumonia (COP) is a disease of unknown etiology characterized on imaging by multifocal ground glass opacifications and/or consolidation. A wide variety of infectious as well as noninfectious causes may result in a similar histologic pattern. Terminology Organizing pneum...
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Myometrial cysts

Myometrial cysts are cysts seen in the myometrium and these can be differentiated appropriately based on location and sonological or Doppler features. Most commonly they are benign 2. Pathology Etiology They can arise from variable etiology and include 1,2: adenomyosis  most often seen at t...
Article

Enchondromatosis

Enchondromatosis, also known as Ollier disease (see Terminology section), is a non-hereditary, sporadic, skeletal disorder characterized by multiple enchondromas principally located in the metaphyseal regions. Terminology Some authors make a distinction between Ollier disease and enchondromato...
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Coronoid process fracture

Fractures of the coronoid process of the ulna are uncommon and often occur in association with elbow dislocation.  Pathology Mechanism Fracture of the coronoid process is thought to result from elbow hyperextension with either avulsion of the brachialis tendon insertion or shearing off by the...
Article

Hyoid bone

The hyoid bone is a midline "U or horseshoe-shaped" bone that serves as a structural anchor in the mid-neck. It is the only bone in the human body that does not directly articulate with another bone (other than sesamoids). It is a place of convergence of multiple small neck muscles that permit t...
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Muscular attachments of the hyoid bone (mnemonic)

A handy mnemonic to recall the muscle attachments of the hyoid bone. The first sentence is for six muscles attaching superiorly, the second sentence is for three muscles attaching inferiorly. Both sentences are in order from lateral to medial: Christopher, He Didn't See Girls Much. That's Obvio...
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Renal artery aneurysm

Renal artery aneurysms (RAA) are the second most common visceral aneurysms (15-22%), the most common being splenic artery aneurysms (60%).  Epidemiology Renal artery aneurysms occur in ~0.1% of the population 6,8,10. They are more common in females 6. The median age at diagnosis is 50 years 8....
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Lung cancer (staging - IASLC 9th edition)

The IASLC (International Association for the Study of Lung Cancer) 9th edition lung cancer staging system was introduced in 2025 and supersedes the IASLC 8th edition. It is a TNM staging system. There are only minor differences from the 8th edition. no changes to the T staging. subdivision of...
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