====== Mohr-Tranebjaerg Syndrome ======
[[Deafness]]-[[dystonia]]-[[optic neuronopathy]] (DDON) [[syndrome]], also known as Mohr-Tranebjærg syndrome, is characterized by [[hearing loss]] that begins early in life, problems with [[movement]], impaired [[vision]], and [[behavior]] problems. This condition occurs almost exclusively in [[male]]s.

===== Case reports =====

Coenen et al. from the Department of Stereotactic and Functional Neurosurgery, Department of Neurology and Neurophysiology, Department of Neuroradiology, University Hospital [[Freiburg]] and Parkinson-Klinik Wolfach, [[Germany]], reported a 28-year-old man presented with a history of sensorineural deafness since early [[childhood]] treated with bilateral [[cochlear implant]]s (CIs). He showed signs of debilitating dystonia that had been present since puberty. Dystonic symptoms, especially a protrusion of the [[tongue]] and bilateral [[hand tremor]], had not responded to [[botulinum toxin]] therapy. They diagnosed Mohr-Tranebjaerg syndrome (MTS).

[[Deep brain stimulation]] (DBS) of the bilateral [[globus pallidus internus]] was performed predominantly with stereotaxic [[computed tomography angiography]] guidance under [[general anesthesia]]. [[Electrophysiology]] was used to identify the target regions and to guide [[DBS]] [[electrode]] placement.

In the immediate postoperative course and stimulation, the patient showed marked improvement of facial, extremity, and [[cervical dystonia]]. More than 2 years after implantation, his dystonic symptoms had dramatically improved by 82%.

The use of DBS for the dystonia in MTS was previously described but not in the presence of bilateral CIs.

DBS in MTS may be a viable option to treat debilitating dystonic symptoms. They describe successful DBS surgery, despite the presence of bilateral CIs, and stimulation therapy over 2 years
((Coenen VA, Rijntjes M, Sajonz B, Piroth T, Prokop T, Jost W, Trippel M, Urbach
H, Reinacher PC. Bilateral Globus Pallidus Internus Deep Brain Stimulation in a
Case of Progressive Dystonia in Mohr-Tranebjaerg Syndrome with Bilateral Cochlear
Implants. J Neurol Surg A Cent Eur Neurosurg. 2018 Oct 5. doi:
10.1055/s-0038-1669472. [Epub ahead of print] PubMed PMID: 30290379.
)).
----
Eggink et al. from the Department of Neurology, Department of Genetics, Department of Rehabilitation, Department of Neurosurgery, University Medical Center [[Groningen]], The [[Netherlands]], reported two patients with dystonia-deafness syndrome due to a beta-actin gene mutation.

They report on disease course, genetic testing, and management of 2 patients, mother and daughter, presenting with dystonia-deafness syndrome.

After exclusion of known dystonia-deafness syndrome causes, whole-exome sequencing revealed a beta-actin gene mutation (p.Arg183Trp) in both patients. Although beta-actin gene mutations are generally associated with developmental Baraitser-Winter syndrome, dystonia-deafness syndrome has been reported once in identical twin brothers. Bilateral GPi-DBS led to a significant decrease of dystonia and regain of independency in our patients.

The p.Arg183Trp mutation in the beta-actin gene is associated with the clinical presentation of dystonia-deafness syndrome, even with only minimal or no developmental abnormalities of Baraitser-Winter syndrome. GPi-DBS should be considered to ameliorate the invalidating dystonia in these patients.
((Eggink H, van Egmond ME, Verschuuren-Bemelmans CC, Schönherr MC, de Koning TJ,
Oterdoom DL, van Dijk JM, Tijssen MA. Dystonia-deafness syndrome caused by a
β-actin gene mutation and response to deep brain stimulation. Mov Disord. 2017
Jan;32(1):162-165. doi: 10.1002/mds.26842. Epub 2016 Nov 8. PubMed PMID:
27862284.
)).
----
Cif et al. reported in 2013 the article Progressive dystonia in Mohr-Tranebjaerg syndrome with cochlear implant and deep brain stimulation
((Cif L, Gonzalez V, Garcia-Ptacek S, James S, Boetto J, Seychelles A, Roujeau
T, Moura De Ribeiro AM, Sillon M, Mondain M, Coubes P. Progressive dystonia in
Mohr-Tranebjaerg syndrome with cochlear implant and deep brain stimulation. Mov
Disord. 2013 Jun;28(6):737-8. doi: 10.1002/mds.25519. PubMed PMID: 23801560.
)).

===== References =====