Skin type classification systems

Systemic PUVA is approved for the treatment of psoriasis. It consists of oral ingestion of a potent photosensitizer such as methoxsalen (8-methoxypsoralen) at aconstant dose (0.6 to 0.8 mg/kg) and variable doses of UVA, depending on patient skin type and history of previous response to ultraviolet radiation (see Table 96-6 for skin type classifications ). Approximately 2 hours after ingesting psoralen, the patient is exposed to UVA light. Photochemotherapy is performed two or three times a week. In most patients, control and partial clearing occurs by the twenty-fifth treatment. 

However, there are times when the immune system acts in an exaggerated manner leading to tissue damage. This is referred to as hypersensitivity. In the classic Coombs and Cell classification system, there are four types of hypersensitivity reactions. The first three (types 1-3) are mediated by antibody (e.g., IgG, IgE). The fourth type (type 4) is mediated by antigen-specific T cells and is also known broadly as delayed-type hypersensitivity (DTH). It is delayed because the reaction appears hours to days after antigen crosses into the skin. Though often thought of as... 

Analyzing the patient with photoaging skin must take into account skin color and skin type as well as the degree of photoaging. Various classification systems have been available and the author would like to present a combination of three systems that would simplify and help the physician define the right program or therapeutic procedure for his patient. Thus the specific problems the patient presents can be paired with the correct solutions. 

A number of industrial chemicals were screened using AFNOR protocols with rabbits as the test systems. Information on the appearance and irritancy potential of different chemicals (and the classification thereof) offers valuable clues to the worker to avoid skin injury (Table 16-4). Certain drugs normally used by humans can cause adverse effects on eyes. The types of ocular disturbance are blurring of vision and diplopia, impairment of visual acuity, yellow vision (xanthopsia), corneal opacities, and lenticular opacities and drugs producing or precipitating the formation of cataract, which have been implicated with the use of candidate drugs. 

DOT CLASSIFICATION 6.1 Label Poison OSHA PEL TWA 0.5 mg(As)/m3 SAFETY PROFILE Human poison by inhalation. Poison experimentally by intravenous route. Human systemic effects by inhalation changes in function or structure of salivary glands, nausea or vomiting, cough. May be irritating to skin, eyes, and mucous membranes. A vomiting type of poison gas (non-persistent). When heated to decomposition it emits very toxic fumes of As and CT. See also ARSENIC COMPOUNDS. 

We know from skin cancer research that a unique feature is not sufficient to diagnose precisely skin cancer, and that the combination of different criteria is the key to the early detection of malignant melanoma and other types of skin cancer. Combining color and structure features for classification, as done in this research, show that measuring these features can be a good guide for a diagnostic system to classify skin lesions. 

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