Hyperacusis is the increased sensitivity to sound and a low tolerance for environmental noise. Definitions of hyperacusis can vary significantly; it can refer to normal noises being perceived as: loud, annoying, painful, fear-inducing, or a combination of those, and is often categorized into four subtypes: loudness, pain, annoyance, and fear.It can be a highly debilitating hearing disorder. Hyperacusis is often coincident with tinnitus. The latter is more common and there are important differences between their involved mechanisms.Little is known about the prevalence of hyperacusis, in part due to the degree of variation in the terms definition. Reported prevalence in children and adolescents ranges from 3% to 17%. Signs and symptoms
In hyperacusis, the symptoms are ear pain, annoyance, distortions, and general intolerance to many sounds that most people are unaffected by. Crying spells or panic attacks may result from the experience of hyperacusis. It may affect only one or both ears. Hyperacusis can also be accompanied by tinnitus. Hyperacusis can result in anxiety, stress and phonophobia. Avoidant behavior is often a response to prevent the effects of hyperacusis and this can include avoiding social situations. Loudness Hyperacusis
Hyperacusis is most often characterized by a sensitivity to sound, where the perception of loudness is much greater than for a typical person; it is often associated with certain volumes and/or frequencies. Hyperacusis can occur in children and adults, and can be either "short-term" in a duration of weeks to less than a year before recovery, or, less-commonly, "long-term", spanning years and in some cases becoming permanent.
(1997) must be present:
Total or partial agenesis of the corpus callosum
Minor craniofacial anomalies such as macrocephaly or hypertelorism
Moderate to severe psychomotor retardation with hypotonia
PolydactylyThe differential diagnosis includes Greig cephalopolysyndactyly syndrome, orofaciodigital syndrome types I and II, Meckel–Gruber syndrome, Smith–Lemli–Opitz syndrome, Rubinstein–Taybi syndrome, Cockayne syndrome, Aicardi syndrome, Neu–Laxova syndrome, Young–Madders syndrome, oto-palato-digital syndrome type 2, Toriello–Carey syndrome, and Da Silva syndromes. ACLS may be differentiated from Greig cephalopolysyndactyly syndrome by the presence of intracranial cysts.ACLS may be suspected antenatally if a previous child is affected, as any subsequent child has a 25% chance of having ACLS. Obstetric ultrasonography or magnetic resonance imaging can reveal polydactyly and/or cerebral malformations from the 20th week of gestation. Chorionic villus sampling and molecular genetic testing can be performed to confirm whether mutations in disease-associated genes are present.ACLS is an extremely rare disorder, with 34 cases described in the literature as of 2005. Management
Management of ACLS consists mainly of monitoring by a pediatric neuropsychiatrist and supportive therapies or accommodations such as occupational therapy and special education plans. Surgery may be considered in early childhood to remove extra digits in case of polydactyly or resolve orofacial defects such as cleft palate. If present, seizures and renal parenchymal hypertension may be treated with anticonvulsants and antihypertensive drugs, respectively. Patients may be offered genetic and vocational counselling when appropriate. Prognosis
Lifespan may range from stillbirth to normal expectancy depending on severity of hypotonia and onset of epilepsy.