One classification distinguishes "common simple aphthae", accounting for 95% of cases, with 3–6 attacks per year, rapid healing, minimal pain and restriction of ulceration to the mouth; and "complex aphthae", accounting for 5% of cases, where ulcers may be present on the genital mucosa in addition to mouth, healing is slower and pain is more severe. A more common method of classifying aphthous stomatitis is into three variants, distinguished by the size, number and location of the lesions, the healing time of individual ulcers and whether a scar is left after healing (see below). Minor aphthous ulceration
This is the most common type of aphthous stomatitis, accounting for about 80–85% of all cases. This subtype is termed minor aphthous ulceration (MiAU), or minor recurrent aphthous stomatitis (MiRAS). The lesions themselves may be referred to as minor aphthae or minor aphthous ulcers. These lesions are generally less than 10 mm in diameter (usually about 2–3 mm), and affect non-keratinized mucosal surfaces (i.e. the labial and buccal mucosa, lateral borders of the tongue and the floor of the mouth). Usually several ulcers appear at the same time, but single ulcers are possible. Healing usually takes seven to ten days and leaves no scar. Between episodes of ulceration, there is usually an ulcer-free period of variable length. Major aphthous ulceration
This subtype makes up about 10% of all cases of aphthous stomatitis. It is termed major aphthous ulceration (MaAU) or major recurrent aphthous stomatitis (MaRAS).
Regarding chronic subdural hematoma (CSDH) surgery, a postoperative volume of pneumocephalus greater than 15mL puts a patient at increased risk of CSDH recurrence; in fact, for every milliliter of air entering the cranial cavity after CSDH evacuation, the recurrence risk increases by 4%. Efforts are made by neurosurgeons to reduce pneumocephalus volume during surgery, and thus, subsequent brain shift. Additional images
Footnotes


== External links ==