Ana P. Rivera, BS
Medical Student
Baylor College of Medicine
Houston, TX, Texas, United States
Marina Ma, MD
Assistant Professor
Baylor College of Medicine / Texas Children’s Hospital
Houston, Texas, United States
Kimberly C. Davis, PhD
Associate Professor
Baylor College of Medicine/Texas Children's Hospital
Houston, Texas, United States
5-year-old female with akinetic mutism associated with post-operative cerebellar mutism syndrome.
Case Description:
A 5-year-old female with congenital spine dysplasia and tethered cord syndrome developed postoperative strokes in the basilar and vertebral arteries after HALO placement following occiput-C3 fusion and tethered cord release. The patient subsequently underwent two craniectomies and partial cerebellar lobectomy. She was admitted to an inpatient rehabilitation unit to maximize her functional recovery. On admission, she had low and inconsistent environmental responses with multiple differential diagnoses including posterior fossa syndrome/cerebellar mutism syndrome (CMS), locked-in syndrome, and disorders of consciousness (DoC). Neuropsychology was consulted and determined her presentation was most consistent with akinetic mutism associated with post-operative CMS given underlying mechanism and location of injury, hypotonia, and other non-diagnostic signs such as ocular motor dysmetria and cranial nerve palsy. Throughout her stay, she made significant progress in all aspects of her function.
Discussions:
Akinetic mutism presents with intact consciousness and sensorimotor capacity, but profound apathy and minimal spontaneous movement. This can be challenging to distinguish from a clinical state where consciousness is reduced. In this patient, the location of her brain injury, alongside cerebellar and brainstem findings (e.g., ocular motor dysmetria, cranial nerve palsy), supports a diagnosis of CMS. Mixed tone or hypotonia can also help distinguish CMS from DoC. Hypotonia can occur early in DoC however it is highly unusual for this sequela to persist.
Conclusions:
There is limited research and no standardized assessment to distinguish between CMS and DoC clinically. Assessment by neuropsychology combined with observations made by the multidisciplinary team, including PT, OT, speech, and PM&R, were essential for diagnosis and prognostication. This case underscores the importance of collaboration between team members and emphasizes CMS as a critical diagnosis to consider in children with posterior fossa insults and low environmental responses given that prognosis can vary significantly.
