Demodex is a genus of tiny mites that live in or near hair follicles of mammals. Around 65 species of Demodex are known. Two species live on humans: Demodex folliculorum and Demodex brevis, both frequently referred to as eyelash mites. Different species of animals host different species of Demodex. Demodex canis lives on the domestic dog. Infestation with Demodex is common and usually does not cause any symptoms, although occasionally some skin diseases can be caused by the mites. Demodex is derived from Greek δημός dēmos "fat" and δήξ dēx, "woodworm".
Demodex miteDemodex canisDemodex caprae
shuntventriculoperitoneal shuntcerebrospinal fluid shunts
Cerebral shunts are commonly used to treat hydrocephalus, the swelling of the brain due to excess buildup of cerebrospinal fluid (CSF). If left unchecked, the cerebrospinal fluid can build up leading to an increase in intracranial pressure (ICP) which can lead to intracranial hematoma, cerebral edema, crushed brain tissue or herniation. The cerebral shunt can be used to alleviate or prevent these problems in patients who suffer from hydrocephalus or other related diseases. Shunts can come in a variety of forms but most of them consist of a valve housing connected to a catheter, the end of which is usually placed in the peritoneal cavity.
The hair follicle is a dynamic organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between hormones, neuropeptides and immune cells. This complex interaction induces the hair follicle to produce different types of hair as seen on different parts of the body. For example, terminal hairs grow on the scalp and lanugo hairs are seen covering the bodies of fetuses in the uterus and in some new born babies. The process of hair growth occurs in distinct sequential stages.
demodectic mangedemodecticDemodex Mange
Demodicosis may also cause itching, swelling, and erythema of the eyelid margins. Scales at the base of the eyelashes may develop. Typically, patients complain of eyestrain. Minor cases of demodectic mange usually do not cause much itching but might cause pustules, redness, scaling, leathery skin, hair loss, skin that is warm to the touch, or any combination of these. It most commonly appears first on the face, around the eyes, or at the corners of the mouth, and on the forelimbs and paws. It may be misdiagnosed as a "hot spot" or other skin ailment.
congenitalcongenital disorderbirth defects
A birth defect, also known as a congenital disorder, is a condition present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth defects are divided into two main types: structural disorders in which problems are seen with the shape of a body part and functional disorders in which problems exist with how a body part works. Functional disorders include metabolic and degenerative disorders. Some birth defects include both structural and functional disorders.
The nuclei of two pairs of cranial nerves are similarly located at the ventral side of the periaqueductal grey – the pair of oculomotor nuclei (which control the eyelid, and most eye movements) is located at the level of the superior colliculus, while the pair of trochlear nuclei (which helps focus vision on more proximal objects) is located caudally to that, at the level of the inferior colliculus, immediatetly lateral to the dorsal raphe nucleus.
In medicine, a disease is considered asymptomatic if a patient is a carrier for a disease or infection but experiences no symptoms. A condition might be asymptomatic if it fails to show the noticeable symptoms with which it is usually associated. Asymptomatic infections are also called subclinical infections. Other diseases (such as mental illnesses) might be considered subclinical if they present some but not all of the symptoms required for a clinical diagnosis. The term clinically silent is also used.
Trichiasis in dogs is hair from the eyelid growing in the wrong direction and rubbing on the eye, causing irritation. It usually occurs at the lateral upper eyelid, especially in the English Cocker Spaniel. Trichiasis also refers to hair from a nasal fold rubbing on the eye. This type of trichiasis can be flattened by rubbing petroleum jelly onto it, but surgery is sometimes necessary for permanent correction. Inferior punctate epitheliopathy. Corneal ulceration. Pannus. Distichiasis. Madarosis. Trachoma.
optic tectumsuperior colliculicolliculi
The superior colliculus (Latin, upper hill) is a structure lying on the roof of the mammalian midbrain. In non-mammalian vertebrates the homologous structure, is known as the optic tectum or optic lobe. The adjective form tectal is commonly used for both structures.
Allergies, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include red eyes, an itchy rash, sneezing, a runny nose, shortness of breath, or swelling. Food intolerances and food poisoning are separate conditions.
Edema, also spelled oedema or œdema, is an abnormal accumulation of fluid in the body's tissue, and can cause severe pain. The word derives from the Greek οἴδημα oídēma meaning "swelling". The condition is also known (mostly archaic) as dropsy.
Damage to the oculomotor nerve (III) can cause double vision (diplopia) and inability to coordinate the movements of both eyes (strabismus), also eyelid drooping (ptosis) and pupil dilation (mydriasis). Lesions may also lead to inability to open the eye due to paralysis of the levator palpebrae muscle. Individuals suffering from a lesion to the oculomotor nerve may compensate by tilting their heads to alleviate symptoms due to paralysis of one or more of the eye muscles it controls. Damage to the trochlear nerve (IV) can also cause diplopia with the eye adducted and elevated. The result will be an eye which can not move downwards properly (especially downwards when in an inward position).
A neoplasm is a type of abnormal and excessive growth, called neoplasia, of tissue. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and it persists growing abnormally, even if the original trigger is removed. This abnormal growth usually (but not always) forms a mass. When it forms a mass, it may be called a tumor.
basal cell carcinomabasal cell cancerrodent ulcer
The following methods are employed in the treatment of basal-cell carcinoma (BCC): A weakness with standard surgical excision is a reported higher recurrence rate of basal-cell cancers of the face, especially around the eyelids, nose, and facial structures. There is no clear approach for treating basal-cell carcinoma around the eye. A diagram on page 38 of the National Comprehensive Cancer Network publication demonstrate the area of high risk of recurrence as being most of the face with the exception of the central cheek and upper forehead.
The Edinger–Westphal nucleus (accessory oculomotor nucleus) is the parasympathetic pre-ganglionic nucleus that innervates the iris sphincter muscle and the ciliary muscle.
In biology, tissue is a cellular organisational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
eczemaallergic dermatitischronic eczema
Dermatitis, also known as eczema, is a group of diseases that result in inflammation of the skin. These diseases are characterized by itchiness, red skin and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to the entire body.
A topical medication is a medication that is applied to a particular place on or in the body. Most often topical administration means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes including creams, foams, gels, lotions, and ointments. Many topical medications are epicutaneous, meaning that they are applied directly to the skin. Topical medications may also be inhalational, such as asthma medications, or applied to the surface of tissues other than the skin, such as eye drops applied to the conjunctiva, or ear drops placed in the ear, or medications applied to the surface of a tooth.
arteriovenous malformationsintracranial arteriovenous malformationscerebral AVM
A cerebral arteriovenous malformation (cerebral AVM, CAVM, cAVM) is an abnormal connection between the arteries and veins in the brain—specifically, an arteriovenous malformation in the cerebrum.
Congenital toxoplasmosistoxoplasmosis, cerebraltoxoplasmosis, congenital
Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii. Infections with toxoplasmosis usually cause no obvious symptoms in adults. Occasionally, people may have a few weeks or months of mild, flu-like illness such as muscle aches and tender lymph nodes. In a small number of people, eye problems may develop. In those with a weak immune system, severe symptoms such as seizures and poor coordination may occur. If infected during pregnancy, a condition known as congenital toxoplasmosis may affect the child.
anatomical variantanatomic variationvariant
An anatomical variation, anatomical variant, or anatomical variability is a difference between the anatomical structures of animals from the same species. The variations are seen as normal in the sense that they are found consistently among different individuals, are mostly without symptoms, and are termed anatomical variations rather than abnormalities. Some variations are found in different species such as polydactyly, having more than the usual number of digits.
posterior fossacranial fossa, posteriorcranial cavity
The posterior cranial fossa is part of the cranial cavity, located between the foramen magnum and tentorium cerebelli. It contains the brainstem and cerebellum.
The Caucasian race (also Caucasoid or Europid) is a grouping of human beings historically regarded as a biological taxon, which, depending on which of the historical race classifications is used, has usually included ancient and modern populations from Europe, Western Asia, Central Asia, South Asia, North Africa, and the Horn of Africa.
Niemann-Pick diseaseNiemann Pick diseaseNiemann-Pick
Niemann–Pick disease is a group of severe inherited metabolic disorders, in which sphingomyelin accumulates in lysosomes in cells (the lysosomes normally transport material through and out of cells).