Articles

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More than 200 results
Article

Thymic cyst

Thymic cysts are cysts that occur within or arise from the thymus. Epidemiology Thymic cysts are uncommon lesions, estimated to account for approximately 1-3% of all anterior mediastinal masses 4. However, they are reported to be the second most common type of primary mediastinal cyst 7.  Ass...
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Anderson and Montesano classification of occipital condyle fractures

The Anderson and Montesano classification is a widely used system for describing occipital condyle fractures. It divides injuries into three types based on morphology and mechanism of injury 1-5. Classification type I: impacted type occipital condyle fracture morphology: comminution of the co...
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Orthopantomography

The orthopantomogram (also known as an orthopantomograph, pantomogram, OPG or OPT) is a panoramic single image radiograph of the mandible, maxilla and teeth. It is often encountered in dental practice and occasionally in the emergency department; providing a convenient, inexpensive and rapid way...
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Tinnitus causes (mnemonic)

A mnemonic to remember the commonest causes of tinnitus is: HAMMER ​Mnemonic H: hypertension A: anemia / acoustic neuroma M: migraine / Menière's disease M: medication (quinine, NSAIDs, streptomycin)  E: ear pathology (wax, foreign body, otitis media)  R: rare (temporomandibular joint ...
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Dacryocystography

Dacryocystography (DCG) is a fluoroscopic contrast examination of the nasolacrimal apparatus. The nasolacrimal duct is cannulated enabling iodinated contrast to be instilled into the nasolacrimal system. Indications The most frequent indication is epiphora: excessive tearing or watering of the...
Article

External auditory canal atresia

External auditory canal atresia, also known as congenital aural atresia, is characterized by complete or incomplete bony atresia of the external auditory canal (EAC), often in association with a dysplastic auricle and an abnormal middle ear cavity or ossicles. Epidemiology The incidence is 1 i...
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External ear

The external ear (or outer ear) comprises the auricle (or pinna), the external auditory meatus, and the tympanic membrane ("eardrum"). The auricle concentrates and amplifies sound waves and funnels them through the outer acoustic pore into the external auditory meatus to the tympanic membrane. ...
Article

Hypermetropia

Hypermetropia, also known as long-sightedness or hyperopia, is a refractive disorder. Though it can happen in any age group, it usually starts from mid-late adulthood. Clinical presentation In this condition, distant objects are seen better than close objects. Pathology The blurriness of nea...
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Ciliopathies

Ciliopathies refer to diseases due to malfunctioning cilia (singular: cilium). Cilia are organelles that are external extensions of the cell membrane. Cilia fall into two main types: primary (or immotile) cilia and motile cilia.  Clinical presentation Primary cilia are found in virtually every...
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Facial nerve

The facial nerve is the seventh (CN VII) cranial nerve and comprises two roots, a motor root and a smaller mixed sensory, taste and parasympathetic root, known as nervus intermedius, which join together within the temporal bone (TA: nervus facialis or nervus cranialis VII). The facial nerve has...
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Canalis basilaris medianus

The canalis basilaris medianus (median basal canal), also known as clival canal, median clival canal, or inferior median clival canal, refers to a number of anatomic variant midline canals in the clivus, typically involving the basioccipital portion. Gross anatomy These canals are generally we...
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Küttner tumor

Küttner tumor refers to a chronic sclerosing sialadenitis. Despite the term tumor, it is a non-neoplastic condition. It is classically described in relation to the submandibular gland but less commonly can also affect the other salivary glands 9 and occasionally also the lacrimal gland 6. Termi...
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Modiolus (mouth)

The modiolus (plural: modioli), also known as the modiolus anguli oris or commissural modiolus, is a small fibromuscular structure at the corner of the mouth where fibers from multiple facial muscles converge, and helps coordinate the action of these muscles. Gross anatomy The convergence of t...
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Kimura disease

Kimura disease, also known historically as eosinophilic hyperplastic lymphogranuloma, is a rare benign inflammatory disease that characteristically manifests as enlargement of cervical lymph nodes and salivary glands. Epidemiology Kimura disease typically affects males (80%) between 20-40 year...
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Lemierre syndrome

Lemierre syndrome, also known as postanginal septicemia, refers to thrombophlebitis of the internal jugular vein(s) with distant metastatic anaerobic septicemia in the setting of initial bacterial oropharyngeal infection such as pharyngitis/tonsillitis into lateral pharyngeal spaces of the neck ...
Article

Multinodular goiter

Multinodular goiter (MNG) is defined as an enlarged thyroid gland (i.e. goiter) due to multiple nodules which may have normal, decreased or increased function.  Terminology When increased activity and hyperthyroidism are present then the condition is referred to as a toxic multinodular goiter ...
Article

Primary cutaneous melanoma

Primary cutaneous melanoma is the most common subtype of melanoma, a malignant neoplasm that arises from melanocytes. Melanocytes predominantly occur in the basal layer of the epidermis but do occur elsewhere in the body. Primary cutaneous melanoma is by far the most common type of primary melan...
Article

Periodontitis

Periodontitis is an inflammatory disease affecting the supporting tissues of the teeth. It is a common cause of tooth loss, particularly in the adult population. Terminology Different forms of periodontitis are recognized. The terms 'chronic periodontitis' and 'aggressive periodontitis' have b...
Article

Cirsoid aneurysm

Cirsoid aneurysms are rare arteriovenous malformations of the scalp and extremities.  Clinical presentation Patients often present with a slow-growing pulsatile mass and may also experience bleeding, tinnitus and/or a headache 3.  Pathology Cirsoid aneurysms develop due to an abnormal arteri...
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Sutural diastasis

Sutural diastasis is an abnormal widening of the skull sutures. It may be physiological in a neonate during a growth spurt.  Pathology In non-traumatic scenarios accelerated growth of the sutural connective tissue without concurrent ossification is the underlying pathology.  Etiology traumat...

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