Characteristics of injury of the corticospinal tract and corticoreticular pathway in hemiparetic patients with putaminal hemorrhage

Abstract

BackgroundNo study on the characteristics of injury of the corticospinal tract (CST) or corticoreticular pathway (CRP) in patients with putaminal hemorrhage has been reported. In this study, using diffusion tensor tractography, we attempted to investigate the characteristics of injury of the CST and CRP in hemiparetic patients with putaminal hemorrhage.MethodFifty seven consecutive patients with putaminal hemorrhage and 57 healthy control subjects were recruited for this study. Diffusion tensor imaging was performed during the early period (8 ~ 30 days) after onset. We defined injury of the CST or CRP in terms of the configuration (discontinuation of a neural tract) or abnormal DTT parameters (the fractional anisotrophy value or fiber number was more than two standard deviations lower than that of normal control subjects). The Motricity Index, the modified Brunnstrom Classification, and the Functional Ambulation Categories were used for evaluation of motor function.ResultsAmong 57 patients, injury of the CST was found in 41 patients (71.9%) and injury of the CRP was found in 50 patients (87.8%), respectively, and 37 patients (64.9%) had injury of both the CST and CRP. All three motor functions of patients with injury of both the CST and CRP were significantly lower than those of patients with injury of either the CST or CRP (p < 0.05).ConclusionOur results indicate that the putaminal hemorrhage frequently accompanies injury of both the CST and CRP, and the CRP appears to be more vulnerable to putaminal hemorrhage than the CST. These findings suggest the necessity for evaluation of both the CRP and the CST in patients with putaminal hemorrhage.

Prognosis and Recovery of Motor Function with Lesion–Symptom Mapping in Patients with Stroke

“…In addition, the intact PMC showed better recovery in terms of mobility and motor function of the hip [50]. Motor functions of patients with injury to both the CST and CRP were significantly poorer than those in patients with injury to either the CST or CRP [44]. Putaminal hemorrhage frequently accompanies injuries to both the CST and CRP, and the CRP appears to be more vulnerable than the CST.…”

“…Putaminal hemorrhage frequently accompanies injuries to both the CST and CRP, and the CRP appears to be more vulnerable than the CST. These findings suggest the need for evaluating both the CRP and the CST in patients with putaminal hemorrhage [44].…”

“…Therefore, determining the state of the CST and CRP is important for determining the cause of motor weakness in stroke patients. Although it lacked statistical power, a study by Yoo et al [44] suggested that patients with injury to the CST, which is closely related to hand function, showed worse hand function than did patients with injury to the CRP, and patients with injury to the CRP, which is more closely related to poor recovery of gait function. The CRP originates primarily from the premotor cortex (PMC) and terminates at the pontomedullary reticular formation (PMRF) [43].…”

Corticoreticular Tract in the Human Brain: A Mini Review

“…However, other studies could not describe the status of the CST clearly (8, 40, 41). In 2013, Yeo et al reported on a patient who showed proximal weakness (MRC scores: shoulder abductor, 3 + ; hip flexor, 3 + ) following traumatic contusional hemorrhage (41, 43).…”

“…Several studies have reported on the characteristics of motor weakness due to CRT injury in patients with brain injury (7, 8, 40, 41). However, precise estimation of the portion of the affected motor function for which the CRT is responsible is difficult because patients with brain injury usually have concomitant simultaneous injuries of other neural tracts associated with motor function such as the CST or the corticofugal tracts from the secondary motor area (6, 42).…”