Introduction 

   Akinetic mutism (AM) is a syndrome characterized by lack of responsiveness in the presence of apparently preserved vigilance.¹⁾ It is neurological state with total immobility (but not paralysis) except for eye movements and complete absence of all other types of communication.¹¹⁾ AM has been rarely linked directly to spontaneous subarachnoid hemorrhage (SAH). 
   Most common cause of AM in patients with SAH is secondary infarction in the distal anterior cerebral artery (DACA) territory.⁴⁾⁵⁾ Sometimes post-SAH hydrocephalus has also been implicated in a delayed form of AM because of disruption of dopaminergic pathway.²⁾⁸⁾ We report a patient who had AM following spontaneous SAH. 

Case report 

   The patient was 64-year-old woman who presented with sudden bursting headache without neurological deficit. She was referred from the other hospital with a diagnosis of spontaneous SAH on head computed tomography(CT) which showed high density on sylvian, interhemispheric fissures and basal cisterns (Fig. 1). We performed computed tomographic cerebral angiography (CTA) and trans-femoral catheter cerebral angiography (TFCA), that revealed no causative intracranial aneurysm, arterial dissection, or other vascular abnormality for the SAH (Fig. 2, 3). 
   At the seven days after admission, she developed drowsy mentality and 10 days after, she presented with stuporous mentality, inability to speak and grade 4 motor weakness of all limbs. She had transcranial Doppler that indicate only mild degree cerebral vasospasm. On the 14th day in hospital, we took the second TFCA, which demonstrated only mild degree focal vasospasm without any causative vascular pathology (Fig. 4). We tried hypertensive hypervolemic therapy with inotropic agent, but we stopped it in a day due to tachycardia. On the 24th hospital day, she developed mutism and grade 3 motor weakness of all limbs without spontaneous movement. We, then performed brain MRI and it showed ventriculomegaly and tiny microangiopathy on the periventricular white matter (Fig. 5). On the 29th hospital day, we prescribed levodopa. And we also took RI cisternography without lumbar drainage on the 32th hospital day, which showed persistent lateral ventricular reflux and migratory delay of tracer to the cerebral convexities (Fig. 6). We could conclude type 4 communicating hydrocephalus.⁹⁾ On the 33th hospital day, she showed neurological recovery with drowsy mentality and grade 4 weakness of all limbs, but suffered mild intention tremor. On the 43th hospital day, we performed the third TFCA, which also revealed no causative vascular abnormality and patient had good neurological recovery with alert mentality andno motor deficit, but she suffered intention tremor as ever. A lumbar puncture and therapeutic drainage performed on the 44th hospital day, and at this time lab finding was noted negative with patient's mentality remained alert. We planned to place ventriculoperitoneal shunt and discussed it with her family. Her family hesitated to consent to surgery. On the 55th hospital day, she was observed to suddenly develop general weakness and cardiac arrest. Efforts to resuscitate her failed, no more treatment could not be applied. 

Discussion 

   Akinetic mutism (AM) describes a standard clinical state characterized by inability to move and inability to speak.⁶⁾ Although, its clinical expression is typical irrespective of the cause, a etiological factors are diverse and various anatomical sites are known to be involved. In some reports, it was classified into anatomically as telencephalic (mainly affecting medial frontal lobes), diencephalic (thalamic/basal ganglia) and mesencephalic (upper brain-stem reticularactivating system).⁸⁾ Most commonly reported causes of akinetic mutism are related to injury of the medial frontal lobes. Freemon reported three cases of akinetic mutism cuased by anterior cingulate lesions due to bilateral anterior cerebral artery infarction.¹²⁾ And AM has also occurred in patients with lesions of diencephalon from hydrocephalus or third ventricular tumors.⁴⁾⁸⁾ Berger et al., reported a case of AM with obstructive hydrocephalus and the possible mechanism is damage to periventricular monoamine projections in the periventricular thalamus and hypothalamus from the third ventricular wall expansion.³⁾ And several workers have reported encouraging response of the AM state to medical treatments with agents like levodopa or bromocriptine.⁷⁾¹³⁾ 
   Despite a consecutive evaluation, the definitive cause of akinetic mutism in out patient was not revealed. The neurological deterioration was initially felt to be caused by an vasospasm. However, patient's neurological status became more aggravated over 3 weeks after admission. Moreover, in our case, we couldn't find infarction in the DACA territory, midbrain or cerebellum except communicating hydrocephalus. And we prescribed levopoda on he 29th hospital day, and also performed RI cisternography without lumbar drainage on the 32th day. But, no lesion in any known ascending dopaminergic pathway was evident on MRI, and therapeutic lumbar drainage was not effective. Finally we planned venticuloperitoneal shunt, but suddenly patient was down to cardiac arrest. We evaluated cardiac status, which revealed myocardiac dysfunction without infarction. And finally, despite intensive care, patient was not recovered. We could not proceed any further evaluation to ascertain patient's pathomechanism for the AM. 

Conclusion 

   We present the case of a 64-year-old woman in whom akinetic mutism developed following subarachnoid hemorrhage. Although the occurrence of AM is not frequent in SAH, this case may alert neurosurgeon to recognize the possibility of such rare complication after spontaneous SAH. 

REFERENCES

1. Ackermann H, Ziegler W. Akinetic mutism-.a review of the literature. Fortschr Neurol Psychiat 63:59-67, 1995 

2. Anderson B. Relief of akinetic mutism from obstructive hydrocephalus using bromocriptine and ephedrine. Case report. J Neurosurg 76:152-5, 1992 

3. Berger L, Gauthier S, Leblanc R. Akinetic mutism and parkinsonism associated with obstructive hydrocephalus. Can J Neurol Sci 12:255-8, 1985 

4. Buge A, Escourolle R, Rancurel G, Poisson M. Akinetic mutism and bicingular softening. 3 anatomo-clinical cases. Rev Neurol (Paris) 131:121-31, 1975 

5. Burruss JW, Chacko RC. Episodically remitting akinetic mutism following subarachnoid hemorrhage. J Neuropsychiat Clin Neurosci 11:100-2, 1999 

6. Cairns H, Oldfield RC, Pennybacker JB, et al. Akinetic mutism with an epidermoid cyst of the 3rd ventricle. With a report on the associated disturbance of brain potentials. Brain 64:273-90, 1941 

7. Caner H, Altinors N, Benli S, Calisaneller T, Albayrak A. Akinetic mutism after fourth ventricle choroid plexus papilloma: treatment with a dopamine agonist. Surg Neurol 51:181-4, 1999 

8. Danilewicz B, Czepko R, Pyrich M, Betlej M, Stachura K, Zawilinski J. Immediate and late results of surgical treatment of hydrocephalus after subarachnoid hemorrhage. Przegl Lek 47:678-81, 1990 

9. Drayer BP, Rosenbaum AE, Higman HB. Cerebrospinal fluid imaging using serial metrizamide CT cisternography. Neuroradiology 13:7-17, 1997 

10. Freemon FR. Akinectic mutism and bilateral anterior cerebral artery occlusion. J Neurol Neurosurg Psychiatry 34:693-8, 1971 

11. Nemeth G, Hegedus K, Molnar L. Akinetic mutism associated with bicingular lesions: clinicopathological and functional anatomical correlates. Eur Arch Psychiat Neurol Sci 237:218-22, 1988 

12. Psarros T, Zouros A, Coimbra C. Bromocriptine-responsive akinetic mutism following endoscopy for ventricular neurocysticercosis. J Neurosurg 99:397-401, 2003 

13. Watahiki Y, Narita S, Kurahashi K, Tanaka T, Matsunaga M. Akinetic mutism from recurrent hydrocephalus: successful treatment with levodopa, bromocriptine and trihexyphenidyl. No To Shinkei 39:977-82, 1987