**4. Conclusion**

288 Hearing Loss

**Gender** M M F F

gastrostomy (PEG) from the age of 4 months and required surgery for gastroesophageal reflux. He also required a tracheostomy between ages of 2 and 5 months.

Moderate bilateral sensorineural hypoacusia (bilateral average threshold of 55 dB on the left and 45 dB HL on the right at 2000- 4000 Hz).

The patient met all the four major and six minor Blake criteria for CHARGE syndrome. Direct sequencing of exon 2 of CHD7 gene revealed the presence of a nonsense mutation: a C→T transition at the nucleotide 925 (c.925C>T) causing a premature stop codon (p.Q309X).

Table 2. Some clinical cases observed at Neonatology Unity of Santa Chiara University

treated at 7 months of age. Echocardiogram showed pulmonary valve stenosis. Brain magnetic resonance imaging (BMRI) revealed dysmature brain

in a

skull.

**Hearing Loss** Bilateral

**Genetic Findings** 

Hospital of Pisa

trigonocephalic

sensorineural hypoacusia: average threshold of 50 dB HL on the right side and 70 dB HL on the left side (2000- 4000 Hz)

High resolution chromosome analysis on PHA-cultured lymphocyte pointed out a male karyotype with a partial 5q duplication and pericentric inversion of chromosome 9 (46,XY, inv9qh, dup(5)(q11.2 q13). Parents did not authorize any cytogenetic studies on themselves

**Case 1 Case 2 Case 3 Case 4** 

Profound bilateral sensorineural hypoacusia (bilateral average threshold above 80 dB at 2000-4000 Hz)

Chromosome analysis revealed a female karyotype with a chromosome deriving from a paternal traslocation: 46XX-11,+der11t(6;11) (11pter→11q24.2::6p22.3→6p

CGH array revealed a microduplication at region 6pter → 6p22.3 in the short arm of chromosome 6 and a microdeletion at the region 11q24.2 →11qter in the long arm of chromosome 11.

ter).

Sensorineural bilateral hypoacusia (bilateral average threshold above 90 dB on the left and 75 dB HL on the right at 2000-4000 Hz). Partially corrected by a Cochlear implant.

Genetic studies showed a female

Karyotype with an interstitial deletion at the long arm of chromosome 9. CGH-Array and FISH pointed out a 10 Mb de novo interstitial deletion in the regionq31.1- 9q31.3.

The knowledge of clinical characteristics of syndromes is still the first and most important step for reaching a correct diagnosis. The clinical appearance leads the clinician to suggest various genetic tests to make a definitive diagnosis. Although many syndromes with craniofacial malformations and hearing loss are known, there are many patients with craniofacial abnormalities and deafness whose disorder cannot be currently classified into any syndrome (Table 2). These patients may have detectable genetic aberrations (e.g. chromosomal abnormalities such as deletions or duplications). The imaging aid to the diagnosis and for intervention in hearing loss associated with these syndromes is certain. The choice between CT o MRI depends on the anatomical/functional damage which causes the hearing.
