Entropion is a medical condition in which the eyelid (usually the lower lid) folds inward. It is very uncomfortable, as the eyelashes continuously rub against the cornea causing irritation. Entropion is usually caused by genetic factors. This is different from when an extra fold of skin on the lower eyelid causes lashes to turn in towards the eye (epiblepharon). In epiblepharons, the eyelid margin itself is in the correct position, but the extra fold of skin causes the lashes to be misdirected. Entropion can also create secondary pain of the eye (leading to self trauma, scarring of the eyelid, or nerve damage). The upper or lower eyelid can be involved, and one or both eyes may be affected. When entropion occurs in both eyes, this is known as "bilateral entropion." Repeated cases of trachoma infection may cause scarring of the inner eyelid, which may cause entropion. In human cases, this condition is most common to people over 60 years of age.

Nocturnal lagophthalmos is the inability to close the eyelids during sleep. It may reduce the quality of sleep, cause exposure-related symptoms or, if severe, cause corneal damage (exposure keratopathy). The degree of lagophthalmos can be minor (obscure lagophthalmos), or quite obvious.

It is often caused by an anomaly of the eyelid that prevents full closure. Treatment may involve surgery to correct the malposition of the eyelid(s). Punctal plugs may be used to increase the amount of lubrication on the surface of the eyeball by blocking some of the tear drainage ducts. Eye drops may also be used to provide additional lubrication or encourage the eyes to increase tear production.

The condition is not widely understood; in at least one instance a passenger was removed from a US Airways flight because of it.

Lagophthalmos is the inability to close the eyelids completely.

Blinking covers the eye with a thin layer of tear fluid, thereby promoting a moist environment necessary for the cells of the exterior part of the eye. The tears also flush out foreign bodies and wash them away. This is crucial to maintain lubrication and proper eye health. If this process is impaired, as in lagophthalmos, the eye can suffer abrasions and infections. Lagopthalmos leads to corneal drying and ulceration.

A symblepharon is a partial or complete adhesion of the palpebral conjunctiva of the eyelid to the bulbar conjunctiva of the eyeball. It results either from disease (conjunctival sequelae of trachoma) or trauma. Cicatricial pemphigoid and, in severe cases, rosacea may cause symblepharon. It is rarely congenital. and its treament

1 ocular movements restricted

2 diplopia

3 lagophthalmos

4 cosmetic cause

types.

Anterior, adhesion in Anterior part

Posterior, adhesion in only fornices

total, adhesion involves whole lens

Complications.

prophylaxis, 1 sweeping a glass rod around fornices several times a day

2 therapeutic soft contact lens

curative treatment t, 1 mobilising surrounding cornea, 2 conjunctival or buccal mucosa graft, 3 amniotic membrane transplant

Entropion has been documented in most dog breeds, although there are some breeds (particularly purebreds) that are more commonly affected than others. These include the Akita, Pug, Chow Chow, Shar Pei, St. Bernard, Cocker Spaniel, Boxer, English Springer Spaniel, Welsh Springer Spaniel, Labrador Retriever, Cavalier King Charles Spaniel, Neapolitan Mastiff, Bull Mastiff, Great Dane, Irish Setter, Shiba Inu, Rottweiler, Poodle and particularly Bloodhound. The condition is usually present by six months of age. If left untreated, the condition can cause such trauma to the eye that it will require removal.

Entropion has also been seen in cat breeds. Typically it is secondary to trauma, or infection leading to chronic eyelid changes. It is also seen secondary to enophthalmos. Congenital cases are also seen with the brachicephalic breeds being over represented.

Upper lid entropion involves the eyelashes rubbing on the eye, but the lower lid usually has no eyelashes, so little or no hair rubs on the eye. Surgical correction is used in more severe cases. A number of techniques for surgical correction exist. The Hotz-Celsus technique involves the removal of strip of skin and orbicularis oculi muscle parallel to the affected portion of the lid and then the skin is sutured.

Alternative techniques such as the Wyman technique focus on tightening the lower eyelid, this technique is not as effective in cases of enophthalmos.

Shar Peis, who often are affected as young as two or three weeks old, respond well to temporary eyelid tacking. The entropion is often corrected after three to four weeks, and the sutures are removed.

Given that episodes tend to occur on awakening and managed by use of good 'wetting agents', approaches to be taken to help prevent episodes include:

- Environmental:

- ensuring that the air is humidified rather than dry, not overheated and without excessive airflow over the face. Also avoiding irritants such as cigarette smoke.

- use of protective glasses especially when gardening or playing with children.

- General personal measures:

- maintaining general hydration levels with adequate fluid intake.

- not sleeping-in late as the cornea tends to dry out the longer the eyelids are closed.

- Pre-bed routine:

- routine use of long-lasting eye ointments applied before going to bed.

- occasional use of the anti-inflammatory eyedrop FML (prescribed by an ophthalmologist or optometrist) before going to bed if the affected eye feels inflamed, dry or gritty

- use of a hyperosmotic (hypertonic) ointment before bed reduces the amount of water in the epithelium, strengthening its structure

- use the pressure patch as mentioned above.

- use surgical tape to keep the eye closed (if Nocturnal Lagophthalmos is a factor)

- Waking options:

- learn to wake with eyes closed and still and keeping artificial tear drops within reach so that they may be squirted under the inner corner of the eyelids if the eyes feel uncomfortable upon waking.

- It has also been suggested that the eyelids should be rubbed gently, or pulled slowly open with your fingers, before trying to open them, or keeping the affected eye closed while "looking" left and right to help spread lubricating tears. If the patient's eyelids feel stuck to the cornea on waking and no intense pain is present, use a fingertip to press firmly on the eyelid to push the eye's natural lubricants onto the affected area. This procedure frees the eyelid from the cornea and prevents tearing of the cornea.

Lid lag is the static situation in which the upper eyelid is higher than normal with the globe in downgaze. It is most often a sign of thyroid eye disease, but may also occur with cicatricial changes to the eyelid or congenital ptosis. Lid lag differs from Von Graefe's sign in that the latter is a dynamic process.It can also be the manifestaition of chemosis (swelling (or edema) of the conjunctiva)

Von Graefe's sign is the lagging of the upper eyelid on downward rotation of the eye, indicating exophthalmic goiter (Graves' Disease). It is a dynamic sign, whereas lid lag is a static sign which may also be present in cicatricial eyelid retraction or congenital ptosis.

A pseudo Graefe's sign (pseudo lid lag) shows a similar lag, but is due to aberrant regeneration of fibres of the oculomotor nerve (III) into the elevator of the upper lid. It occurs in paramyotonia congenita.

A pseudo Graefe's sign is most commonly manifested in just one eye but can occasionally be observed in both. The reason only one eye is affected is not yet clear.

Some of the adverse outcomes associated with intra-operative injuries include:

- Increased length of stay. This is due to ophthalmology consults required, associated infections and treatment.

- Increased costs. This is due to increased length of stay, cost of treating the complications.

- Pain and discomfort for the patient. Corneal abrasions are extremely painful for the patient and the treatment consists of drops and ointments applied in the eye which may cause further discomfort for the patient.

Recurrent corneal erosion is a disorder of the eyes characterized by the failure of the cornea's outermost layer of epithelial cells to attach to the underlying basement membrane (Bowman's layer). The condition is excruciatingly painful because the loss of these cells results in the exposure of sensitive corneal nerves. This condition can often leave patients with temporary blindness due to extreme light sensitivity photophobia.

The most commonly employed method is to use tape or a general purpose adhesive dressing. Unfortunately the adhesive used on the tape or dressing will generally be inappropriate for this use. The adhesive strength may change when reaching body temperature, or over time.

As the operation progresses this can cause the adhesive to stop working and become gooey, allowing the eyelids to move apart, and leaving behind a sticky residue. This leaves the cornea exposed to epithelial drying and/or abrasions, sometimes caused by the tape that was originally applied to protect the cornea. Alternatively, the adhesive strength may increase, which upon removal can result in eyelid bruising, tears, or eyelash removal.

Rolls of tapes are often “laying around” the operating theatre or kept in health care workers' pockets.

Therefore, they can be a source of hospital-acquired infections (HAI's) such as Methicillin-resistant Staphylococcus aureus (MRSA) & Vancomycin-resistant Enterococcus (VRE), with a 2010 study showing that 50% of partially used tape rolls tested positive for MRSA, VRE or both.

Most tapes and dressings are non-transparent and so it is not possible to see if the patient’s eyes are opened or closed throughout the case. It is not uncommon for the eyelids to move open as the case progresses, even with adhesive tapes stuck onto them. In a practical sense, these medical tapes/dressings may be difficult to remove from a patient because their ends can become stuck flush with the skin. The possibility of tape removal causing trauma is also significantly increased in older people, people with sensitive skin, dermatitis, dehydration or side effects of medications.

As noted above, there have been several studies looking at the efficacy and safety of eye ointments/lubricants as adjuncts with tape or as a stand-alone management for intra-operative eye closure. Unfortunately many in common use have problems. Petroleum gel is flammable and is best avoided when electrocautery and open oxygen are to be used around the face. Preservative-free eye ointment is preferred, as preservative can cause corneal epithelial sloughing and conjunctival hyperemia.

They have been implicated in blurred vision in up to 75% of patients and they do not protect from direct trauma.

Specially made eyelid occlusion dressings are available commercially, such as EyeGard (manufactured in the USA by KMI Surgical and marketed by Sharn Anesthesia), EyePro (Andsco Medical Pty Ltd, Australia) and Anesthesia-Aid (Sperian Protection). These dressings overcome most of the problems associated with tape or general purpose dressings.

Risk factors of progressive and severe thyroid-associated orbitopathy are:

- Age greater than 50 years

- Rapid onset of symptoms under 3 months

- Cigarette smoking

- Diabetes

- Severe or uncontrolled hyperthyroidism

- Presence of pretibial myxedema

- High cholesterol levels (hyperlipidemia)

- Peripheral vascular disease

The pathology mostly affects persons of 30 to 50 years of age. Females are four times more likely to develop TAO than males. When males are affected, they tend to have a later onset and a poor prognosis. A study demonstrated that at the time of diagnosis, 90% of the patients with clinical orbitopathy were hyperthyroid according to thyroid function tests, while 3% had Hashimoto's thyroiditis, 1% were hypothyroid and 6% did not have any thyroid function tests abnormality. Of patients with Graves' hyperthyroidism, 20 to 25 percent have clinically obvious Graves' ophthalmopathy, while only 3–5% will develop severe ophthalmopathy.

Many conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square meters, and is made of three distinct layers: the epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin. Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. In the embryo, the epidermis, hair, and glands form from the ectoderm, which is chemically influenced by the underlying mesoderm that forms the dermis and subcutaneous tissues.

The epidermis is the most superficial layer of skin, a squamous epithelium with several strata: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. Nourishment is provided to these layers by diffusion from the dermis, since the epidermis is without direct blood supply. The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95 percent of the epidermis. This stratified squamous epithelium is maintained by cell division within the stratum basale, in which differentiating cells slowly displace outwards through the stratum spinosum to the stratum corneum, where cells are continually shed from the surface. In normal skin, the rate of production equals the rate of loss; about two weeks are needed for a cell to migrate from the basal cell layer to the top of the granular cell layer, and an additional two weeks to cross the stratum corneum.

The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing.

The subcutaneous tissue is a layer of fat between the dermis and underlying fascia. This tissue may be further divided into two components, the actual fatty layer, or panniculus adiposus, and a deeper vestigial layer of muscle, the panniculus carnosus. The main cellular component of this tissue is the adipocyte, or fat cell. The structure of this tissue is composed of septal (i.e. linear strands) and lobular compartments, which differ in microscopic appearance. Functionally, the subcutaneous fat insulates the body, absorbs trauma, and serves as a reserve energy source.

Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying etiologies and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology (chronic blistering conditions), etiology (skin conditions resulting from physical factors), and so on. Clinically, the diagnosis of any particular skin condition is made by gathering pertinent information regarding the presenting skin lesion(s), including the location (such as arms, head, legs), symptoms (pruritus, pain), duration (acute or chronic), arrangement (solitary, generalized, annular, linear), morphology (macules, papules, vesicles), and color (red, blue, brown, black, white, yellow). Diagnosis of many conditions often also requires a skin biopsy which yields histologic information that can be correlated with the clinical presentation and any laboratory data.

This condition has been linked to mutations in the ribosomal GTPase BMS1 gene.

ARN is associated with people who have latent herpes viruses that have been reactivated. The most common causes of the disease have been linked to VSV, HSV-1, HSV-2, and CMV respectively.

ARN cases have been reported in patients who have AIDS, are immunocompromised and in children. The disease is not limited to a specific gender. Most cases have been reported in young adults though children and the elderly can be affected.

Specific genetic markers in Caucasians in the United States have shown elevated risk for disease development (HLA-DQw7 and Bw62, DR4) as well as HLA-Aw33, B44, and DRw6 in the Japanese population.

Junctional epidermolysis bullosa is a skin condition characterized by blister formation within the lamina lucida of the basement membrane zone.

CCCA tends to present itself in the 20s and progresses over 20–30 years. One should consider this diagnosis in African Americans with what appears to be a female-pattern hair loss.

"Junctional epidermolysis bullosa with pyloric atresia" is a rare autosomal recessive form of junctional epidermolysis bullosa that presents at birth with severe mucocutaneous fragility and gastric outlet obstruction. It can be associated with "ITGB4" or "ITGA6".

Aplasia cutis congenita (ACC) is a rare disorder characterized by congenital absence of skin. Frieden classified ACC in 1986 into 9 groups on the basis of location of the lesions and associated congenital anomalies. The scalp is the most commonly involved area with lesser involvement of trunk and extremities. Frieden classified ACC with fetus papyraceus as type 5. This type presents as truncal ACC with symmetrical absence of skin in stellate or butterfly pattern with or without involvement of proximal limbs.]It is the most common congenital cicatricial alopecia, and is a congenital focal absence of epidermis with or without evidence of other layers of the skin.

The exact etiology of ACC is still unclear but intrauterine infection by varicella or herpes virus, drugs such as methimazole, misoprostol, valproate, cocaine, marijuana etc., fetus papyraceus, feto-fetal transfusion, vascular coagulation defects, amniotic membrane adherence, abnormal elastic fiber biomechanical forces and trauma are implicated. It can be associated with Johanson-Blizzard syndrome, Adams-Oliver syndrome, trisomy 13, and Wolf-Hirschhorn syndrome.

It can also seen with exposure to methimazole and carbimazole in utero. This dermatological manifestation has been linked to Peptidase D haploinsufficiency and a deletion in Chromosome 19.

In a study done published by the British Journal of Ophthalmology, the cases of ARN/BARN reported in 2001-2002 in the UK, Varicella Zoster Virus was the most common culprit for the disease and presented mostly in men than in women.

Researchers have also looked at two cases of ARN in patients who have been diagnosed with an immunodeficiency virus. The disease presented itself more so in the outer retina until it progressed far enough to then affect the inner retina. The patients were not so responsive to the antiviral agents given to them through an IV, acyclovir specifically. The cases progressed to retinal detachment. The patients tested positive for the herpes virus. Researchers are now wondering if this type of ARN is specific to those who have the immunodeficiency virus.

In mucous membrane pemphigoid, the autoimmune reaction occurs in the skin, specifically at the level of the basement membrane, which connects the lower skin layer (dermis) to the upper skin layer (epidermis) and keeps it attached to the body.

When the condition is active, the basement membrane is dissolved by the antibodies produced, and areas of skin lift away at the base, causing hard blisters which scar if they burst. In other words, this is a desquamating/blistering disease in which the epithelium "unzips" from the underlying connective tissue, allowing fluid to gather that subsequently manifest as bullae, or blisters.

Cicatricial pemphigoid (also known as "Mucous Membrane Pemphigoid", "MMP", "Benign mucosal pemphigoid," "Benign mucous membrane pemphigoid," "Ocular pemphigus," and "Scarring pemphigoid") is a rare chronic autoimmune subepithelial blistering disease characterized by erosive skin lesions of the mucous membranes and skin that results in scarring of at least some sites of involvement.

Cicatricial pemphigoid has been referred to by a variety of designations based largely on its site of involvements, with examples of such terminology including "desquamative gingivitis," "ocular pemphigus," and "benign mucous membrane pemphigoid." However, currently "...such designations are thought to be confusing or somewhat misleading (e.g., pemphigus in this context is a misnomer, and this disorder is hardly benign given the extent of morbidity it can cause)."

As PNP is ultimately caused by the presence of a tumor, it is not contagious. There is no known way to predict who will become afflicted with it. Patients with cancer are therefore a group at risk. Although PNP has been known to affect all age groups, it is more likely to afflict middle-aged to older patients.

Basal-cell carcinoma is a common skin cancer and occurs mainly in fair-skinned patients with a family history of this cancer. Sunlight is a factor in about two-thirds of these cancers; therefore, doctors recommend sunscreens with at least SPF 30. One-third occur in non-sun-exposed areas; thus, the pathogenesis is more complex than UV exposure as "the" cause.

The use of a chemotherapeutic agent such as 5-Fluorouracil or imiquimod, can prevent development of skin cancer. It is usually recommended to individuals with extensive sun damage, history of multiple skin cancers, or rudimentary forms of cancer (i.e., solar keratosis). It is often repeated every 2 to 3 years to further decrease the risk of skin cancer.