Auditory neuropathy spectrum disorder and cochlear implantation in Chudley- McCullough syndrome (CMS): a case series.
R.A. Boerboom1, S. Engels2, F.A. Ebbens2, P. Merkus2, A.L. Smit1, C. Smits2
1 Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.
2 Department of Otorhinolaryngology – Head and Neck Surgery, Amsterdam University Medical Center , Amsterdam, Netherlands.
Objective
Chudley-McCullough syndrome (CMS) is a rare, autosomal recessive disorder characterized by structural brain abnormalities consisting of frontal polymicrogyria,  cerebellar dysplasia, nodular heterotopia, agenesis of the corpus callosum and arachnoid cysts (OMIM 604213). CMS is also associated with sensorineural hearing loss. To date, there have been close to 30 reported cases of CMS in the literature.
The objective of the current study was to describe the audiological outcome of a case series of patients with CMS, before and after cochlear implantation, in order to support the decision making process in CMS patients regarding cochlear implantation (CI) based on outcomes.
Methods
A retrospective analysis was performed on six patients, from three Dutch clinics, diagnosed with CMS. For each patient the medical history was reviewed on characteristics typical for CMS and on audiological performance from neonatal hearing screening to performance after cochlear implantation.
Results
We will present a detailed description of 6 patients with CMS focusing on the audiological aspects and results of cochlear implantation. Three out of six patients were diagnosed with auditory neuropathy spectrum disorder (ANSD), one patient was suspected of ANSD and in two patients the presence of ANSD could neither be confirmed nor excluded. Hearing aids were fitted in all patients and all with limited benefit. Hearing deteriorated rapidly and eventually all patients received a CI (either unilateral or bilateral). The hearing performance with CI’s varied widely between patients. In general aided thresholds with CI’s were satisfactory. However, speech recognition varied widely between patients and was on average worse than for most CI patients.
Conclusions
In this study a detailed description of the audiological performance of 6 patients with CMS is presented. We show that ANSD is a common finding in patients with CMS. Due to the progression of hearing loss and limited benefit of hearing aids, all patients were eventually implanted with CI’s. Based on the performance of the patients with CMS and CI we conclude that cochlear implantation is a viable option for these patients but hearing performance is significantly lower than for other CI patients. Counseling parents with regard to realistic hearing expectations is important

**Auditory neuropathy spectrum disorder and cochlear implantation in Chudley- McCullough syndrome (CMS): a case series.**
**R.A. Boerboom^1^, S. Engels^2^, F.A. Ebbens^2^, P. Merkus^2^, A.L. Smit^1^, C. Smits^2^**
^1^ Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands.
^2^ Department of Otorhinolaryngology – Head and Neck Surgery, Amsterdam University Medical Center , Amsterdam, Netherlands.
**Objective**
Chudley-McCullough syndrome (CMS) is a rare, autosomal recessive disorder characterized by structural brain abnormalities consisting of frontal polymicrogyria,  cerebellar dysplasia, nodular heterotopia, agenesis of the corpus callosum and arachnoid cysts (OMIM 604213). CMS is also associated with sensorineural hearing loss. To date, there have been close to 30 reported cases of CMS in the literature.
The objective of the current study was to describe the audiological outcome of a case series of patients with CMS, before and after cochlear implantation, in order to support the decision making process in CMS patients regarding cochlear implantation (CI) based on outcomes.
**Methods**
A retrospective analysis was performed on six patients, from three Dutch clinics, diagnosed with CMS. For each patient the medical history was reviewed on characteristics typical for CMS and on audiological performance from neonatal hearing screening to performance after cochlear implantation.
**Results**
We will present a detailed description of 6 patients with CMS focusing on the audiological aspects and results of cochlear implantation. Three out of six patients were diagnosed with auditory neuropathy spectrum disorder (ANSD), one patient was suspected of ANSD and in two patients the presence of ANSD could neither be confirmed nor excluded. Hearing aids were fitted in all patients and all with limited benefit. Hearing deteriorated rapidly and eventually all patients received a CI (either unilateral or bilateral). The hearing performance with CI’s varied widely between patients. In general aided thresholds with CI’s were satisfactory. However, speech recognition varied widely between patients and was on average worse than for most CI patients.
**Conclusions**
In this study a detailed description of the audiological performance of 6 patients with CMS is presented. We show that ANSD is a common finding in patients with CMS. Due to the progression of hearing loss and limited benefit of hearing aids, all patients were eventually implanted with CI’s. Based on the performance of the patients with CMS and CI we conclude that cochlear implantation is a viable option for these patients but hearing performance is significantly lower than for other CI patients. Counseling parents with regard to realistic hearing expectations is important

Auditory neuropathy spectrum disorder and cochlear implantation in Chudley- McCullough syndrome (CMS): a case series.

It is with great pleasure and enthusiasm, that on behalf of the Cochlear Implant centers of the Radboud UMC in Nijmegen and Erasmus MC Sophia Children’s Hospital in Rotterdam to invite you to attend the 16th European Symposium on Pediatric Cochlear Implantation to Rotterdam, the Netherlands in 2023.

Yours sincerely, on behalf of the CI Centers at Radboud UMC and Erasmus MC,