Recovery of akinetic mutism and injured prefronto-caudate tract following shunt operation for hydrocephalus and rehabilitation

Abstract

Rationale:A 76-year-old female patient was diagnosed with an aneurysmal subarachnoid hemorrhage following rupture of a right posterior communicating artery aneurysm.Patient concerns:She was treated surgically with clipping of the aneurysmal neck. Six months after onset, when starting rehabilitation at our hospital, she showed no spontaneous movement or speech.Diagnoses:aneurysmal subarachnoid hemorrhage following rupture of a right posterior communicating artery aneurysm.Interventions:During 2 months’ rehabilitation, her AM did not improve significantly. As there was no apparent change, she underwent a ventriculo-peritoneal shunt operation for hydrocephalus 8 months after her stroke. After the surgery, she remained in the AM state, but participated in a comprehensive rehabilitative management program similar to that before shunt operation. During 1 month's intensive rehabilitation, her AM gradually improved. At 9 months after onset, she became able to perform some daily activities by herself including eating, washing, and dressing. In addition, she could speak with some fluency.Outcomes:On 6-month DTT, the neural connectivity of the caudate nucleus (CN) to the medial prefrontal cortex (PFC, Broadmann area [BA]: 10 and 12) and orbito-frontal cortex (BA 11 and 13) was low in both hemispheres. However, the neural connectivity of the CN to the medial PFC increased on both sides on 9-month DTT. The integrity of the arcuate fasciculus (AF) was preserved in both hemispheres on both 6- and 9-month DTTs.Lessons:Recovery of AM and injured PCTs was observed in a stroke patient.

Differential Diagnosis of Akinetic Mutism and Disorder of Consciousness Using Diffusion Tensor Tractography: A Case Report

“…Severe injury of the fronto-subcortical circuit (particularly, the prefronto-caudate, and prefronto-thalamic tracts) has been suggested as the pathophysiological mechanism of AM (Mega and Cohenour, 1997;Nagaratnam et al, 2004;Jang and Kwon, 2017;Jang et al, 2017aJang et al, ,b, 2018. The upper and lower dorsal ARAS showed an almost normal state in this patient, whereas the prefronto-caudate and prefronto-thalamic tracts revealed severe injuries.…”

“…The introduction of diffusion tensor tractography (DTT), which is derived from diffusion tensor imaging, enables the estimation and visualization of some neural tracts of the fronto-subcortical circuit, including the prefrontocaudate and prefronto-thalamic (mediodorsal nucleus) tracts (Behrens et al, 2007;Leh et al, 2007;Jang and Kwon, 2017). As a result, several DTT-based studies have reported that AM is related to injuries of the above two neural tracts, particularly the prefronto-caudate tract (Jang and Kwon, 2017;Jang et al, 2017aJang et al, ,b, 2018. On the other hand, DTT also allows a reconstruction of the ascending reticular activating system (ARAS), which is an important neural network for controlling consciousness (Jang et al, 2019a,b).…”

Role of Diffusion Tensor Imaging in Diagnosis and Estimation of Shunt Effect for Hydrocephalus in Stroke Patients: A Narrative Review

“…The main advantage of DTT is that the entire neural tract can be evaluated from DTT parameters and configurational analysis (integrity and configuration) [ 17 , 18 , 20 ]. Consequently, the effects of the hydrocephalus or surgical interventions for hydrocephalus on the periventricular neural tracts or structures can be estimated using DTT [ 21 , 22 , 23 , 24 , 25 , 26 ]. Fractional anisotropy (FA: the state of white matter organization because it is a measure of the degree of directionality and integrity of the white matter microstructures), apparent diffusion coefficient (or mean diffusivity)(the magnitude of water diffusion), and tract volume (or fiber number; the number of voxels within a neural tract which represents the number of fibers within of a neural tract) have been commonly used as DTI or DTT parameters [ 12 , 13 , 17 , 18 , 20 ].…”

“…Fractional anisotropy (FA: the state of white matter organization because it is a measure of the degree of directionality and integrity of the white matter microstructures), apparent diffusion coefficient (or mean diffusivity)(the magnitude of water diffusion), and tract volume (or fiber number; the number of voxels within a neural tract which represents the number of fibers within of a neural tract) have been commonly used as DTI or DTT parameters [ 12 , 13 , 17 , 18 , 20 ]. As a result, DTI or DTT for periventricular white matter or neural structures have been suggested as a non-invasive tool for evaluating the presence, severity, and shunt effect of hydrocephalus in stroke patients [ 4 , 8 , 14 , 15 , 21 , 22 , 23 , 24 , 25 , 26 ].…”

“…This study reviewed 10 DTI or DTT-based studies that demonstrated the usefulness of DTI or DTT for evaluating the presence, severity, and shunt effect of hydrocephalus in stroke patients ( Table 1 ) [ 4 , 8 , 14 , 15 , 21 , 22 , 23 , 24 , 25 , 26 ]. This review aims to present the role of DTI in the diagnosis and estimation of the shunt effect for hydrocephalus in stroke patients.…”