Characteristics of injury of the corticospinal tract and corticoreticular pathway in hemiparetic patients with putaminal hemorrhage
© Yoo et al.; licensee BioMed Central Ltd. 2014
Received: 13 December 2013
Accepted: 6 May 2014
Published: 6 June 2014
No 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.
Fifty 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.
Among 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).
Our 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.
KeywordsPutaminal hemorrhage Corticospinal tract Corticoreticular pathway Diffusion tensor imaging Motor function
Spontaneous intracerebral hemorrhage (ICH), comprising 48 ~ 67% of all spontaneous ICH, most commonly occurs in the putamen . Various neural tracts, particularly the neural tracts for motor function, including the corticospinal tract (CST) and corticoreticular pathway (CRP), are located near the putamen, consequently, motor weakness is one of the most common neurological manifestations in patients with putaminal hemorrhage [2–5]. Therefore, clarification of the cause of motor weakness is essential for prognosis and for adoption of scientific strategies for successful rehabilitation [6–11]. However, little is known about this topic.
In the human brain, the neural tracts for motor function are classified according to the CST and the non-CST. The CST and the corticoreticulospinal tract have been regarded as important neural tracts for mediation of voluntary movements [12, 13]. The main function of the CST is control of movements of distal extremities, particularly fine-motor movements of the hand [12–14], while the corticoreticulospinal tract, consisting of the corticoreticular pathway (CRP) and the reticulospinal tract, innervates proximal extremities and axial muscles [9, 15–18]. Therefore, elucidation of the state of the CST and CRP is important for determination of the cause of motor weakness in stroke patients.
Conventional neuroimaging techniques, such as brain CT and MRI have limitations in accurate assessment of neural tracts, including the CST and CRP . By contrast, recently developed diffusion tensor tractography (DTT), derived from diffusion tensor imaging (DTI), enables three-dimensional reconstruction and estimation of the CST and CRP [2, 3, 8–10, 16, 20–25]. Consequently, many studies have reported on injury of the CST or CRP in stroke patients with motor weakness [8–11, 26]. However, no study on the characteristics of injury of the CST or CRP in patients with putaminal hemorrhage has been reported so far.
In this study, using DTT, we attempted to investigate the characteristics of injury of the CST and CRP in hemiparetic patients with putaminal hemorrhage.
Among patients admitted for rehabilitation to the rehabilitation department of a university hospital, 57 consecutive patients (37 males, 20 female; mean age 55.1 years, range 34 ~ 74, right ICH 31, left ICH 26) and 57 age- and sex-matched healthy control subjects (36males, 21 females; mean age 52.6 years, range 33 ~ 67) with no history of neurological or psychiatric problems were recruited for this study. The 57 patients were recruited according to the following criteria: (1) first-ever stroke, (2) age: 20 ~ 75 years, (3) DTI scanning performed at the early stage after ICH: between eight and 30 days after onset, (4) spontaneous putaminal ICH, confirmed by a neuroradiologist, (5) motor weakness in the contralateral extremities of ICH, and (6) no history of neurologic, psychiatric, or traumatic brain disease. This retrospective study was approved by the Institutional Review Board of Yeungnam university hospital.
Motor function was evaluated at the time of DTI scanning, using the Motricity Index (MI), the modified Brunnstrom Classification (MBC), and the Functional Ambulation Categories (FAC) [27–29]. The MI score is a modification of the Medical Research Council scoring system, with a maximum score of 100 . The MBC score is as follows: 1; unable to move fingers voluntarily, 2; able to move fingers voluntarily, 3; able to close hand voluntarily, unable to open hand, 4; able to grasp a card between the thumb and medial side of the index finger, able to extend fingers slightly, 5; able to pick up and hold a glass, able to extend fingers, 6; able to catch and throw a ball in a near-normal fashion, able to button and unbutton a shirt . The FAC was designed for characterization of levels of assistance required during a 15 m walk. The six categories include the following: 0; non-ambulatory, 1; need for continuous support from one person, 2; need for intermittent support from one person, 3; need verbal supervision only, 4; help required on stairs and uneven surfaces, and 5; ability to walk independently anywhere . The reliability and validity of MRC, MI, MBC, and FAC are well established [27–29].
DTI acquisition and analysis
Statistical analysis was performed using SPSS 17.0 for Windows (SPSS Inc., Chicago, Ill., USA). The Kruskal-Wallis test with the Mann–Whitney U post hoc test was used to determine the significance of ICH volume, MI, MBC, and FAC in the four groups and statistical significance was accepted for p < 0.05. Correlations between the ICH volume and MI, MBC, and FAC were determined using Spearman correlation test, and statistical significance was accepted for p < 0.05.
Demographic and clinical data of the patient group
Number of patients, n (%)
Mean age, years
61.0 ± 5.6
50.0 ± 16.5
60.8 ± 10.7
53.3 ± 10.5
Hematoma volume, mV
7.8 ± 0.4
7.5 ± 1.3
9.1 ± 7.1
10.8 ± 6.1
74.6 ± 1.4
64.3 ± 6.9
66.3 ± 7.3
35.5 ± 20.8
5.7 ± 0.6
4.0 ± 1.4
5.0 ± 0.8
2.2 ± 0.9
4.0 ± 0.0
2.8 ± 0.9
2.5 ± 1.8
0.6 ± 0.9
Distribution according to the type of injury of the corticospinal tract and corticoreticular pathway
In the current study, using DTT, we examined the characteristics of injury of the CST and CRP in 57 consecutive hemiparetic patients with putaminal ICH. Our findings were as follows. First, the incidence of injury; group A – 5.3%, group B -7.0%, group C – 22.8%, and group D - 64.9%. Consequently, among the 57 consecutive patients with putaminal hemorrhage, injury of the CST was found in 41 patients (71.9%) and injury of the CRP was found in 50 patients (87.8%). These 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. The greater vulnerability of the CRP appears to be ascribed to the anatomical characteristics of the CST and CRP; the CST and the CRP are located within close proximity to one another and the CRP is located closer to the center of the putamen than the CST in the anteroposterior direction [2, 3]. However, conduct of further studies on this topic will be necessary. Second, the severity of injury of the CST and CRP; CST- type II (17.6%) and type III (54.3%); CRP- type II (17.6%) and type III (70.2%). The FA value is the most commonly used DTI parameter reflecting the degree of directionality of microstructures, such as axons, myelin, and microtubules, [33–35]. The fiber number reflects the total number of voxels in a neural tract . Therefore, the decrement of FA value or of fiber number of a neural tract indicates an injury of the neural tract. Type II may indicate mild or partial injury because this type means the decrement of FA value or fiber number withpreservation of the integrity of a neural tract. By contrast, type III might suggest more severe or complete injury of a neural tract because this type indicates discontinuation of a neural tract. Therefore, our results suggest that in the case of an accompanying putaminal hemorrhage, regarding injury of the CRP, more patients showed more severe injury than that of the CST, although the proportion of mild injury of both neural tracts was the same. The third was the clinical characteristics of the four groups. The average values of three clinical scales were as follows, in order with better function: the MI (general motor function, full score: 100) was as follows: group A, group C, group B, and group D; the MBC (hand function, full score; 6); group A, group C, group B, and group D; the FAC (gait function, full score; 5); group A, group B, group C, and group D. Scores for all motor functions were worse in terms of general motor function, hand function, and gait in patients with injury of both the CST and CRP. Patients with injury of the CST, which is closely related to hand function, showed worse hand function than patients with injury of the CRP, and patients with injury of the CRP, which is more related to gait function, showed lower FAC value than patients with injury of the CST. However, no statistical differences in terms of hand and gait function were observed between the two groups. The fourth was the clinical correlation with the size of hematoma. No significant difference in the volume of hematoma was observed among the four groups and no correlation in terms of the MI, MBC, and FAC was found between ICH volume and all clinical scales. These results indicate that hematoma size is not important to injury of the CST or CRP. On the contrary, it is possible that the location of hematoma is more important in injury of the CST or CRP than the size of hematoma.
In conclusion, we investigated the characteristics of injury of the CST and CRP in 57 hemiparetic patients with putaminal hemorrhage. According to our findings, 64.9% of patients had injury of both the CST and CRP, and the incidence (87.8%) of CRP injury was higher than that (71.9%) of CST injury. Our results indicate that an accompanying putaminal hemorrhage tends to occur in cases involving injury of both the CST and CRP, with greater vulnerability of the CRP than the CST. In addition, patients with injury of the CST and CRP showed worse motor function than patients with injury of either the CST or CRP. These results suggest the necessity for evaluation of both the CRP and the CST in patients with putaminal hemorrhage. Many studies have reported on injury of the CST or CRP in patients with putaminal hemorrhage using DTT [8–11, 26]. However, this is the first study to investigate the characteristics of injury of the CST and CRP in a large number of consecutive patients with putaminal hemorrhage. However, some limitations should be considered in interpretation of this study. First, we recruited the patients among those with putaminal hemorrhage who had been admitted for rehabilitation. Therefore, it is possible that among all patients with putaminal hemorrhage, we recruited patients with severe clinical manifestations. Second, DTI may underestimate fiber tracts due to hematoma or peri-hematomal edema in patients with putaminal hemorrhage. In addition, fiber complexity and crossing fiber effect can prevent reflection of the fiber tracts [36–38]. Therefore, in order to overcome these limitations, conduct of further studies should be encouraged.
Diffusion tensor tractography
Diffusion tensor imaging
Korean-Western aphasia battery
Korean version of the mini mental state examination
Functional magnetic resonance imaging of brain
Apparent diffusion coefficient.
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012R1A1A4A01001873).
- Inagawa T, Ohbayashi N, Takechi A, Shibukawa M, Yahara K: Primary intracerebral hemorrhage in izumo city, japan: Incidence rates and outcome in relation to the site of hemorrhage. Neurosurgery. 2003, 53: 1283-1297. discussion 1297–1288View ArticlePubMedGoogle Scholar
- Jang SH: A review of corticospinal tract location at corona radiata and posterior limb of the internal capsule in human brain. NeuroRehabilitation. 2009, 24: 279-283.PubMedGoogle Scholar
- Yeo SS, Chang MC, Kwon YH, Jung YJ, Jang SH: Corticoreticular pathway in the human brain: Diffusion tensor tractography study. Neurosci Lett. 2012, 508: 9-12.View ArticlePubMedGoogle Scholar
- Daverat P, Castel JP, Dartigues JF, Orgogozo JM: Death and functional outcome after spontaneous intracerebral hemorrhage. A prospective study of 166 cases using multivariate analysis. Stroke. 1991, 22: 1-6.View ArticlePubMedGoogle Scholar
- Ghetti G: Putaminal hemorrhages. Front Neurol Neurosci. 2012, 30: 141-144.View ArticlePubMedGoogle Scholar
- Gillard JH, Papadakis NG, Martin K, Price CJ, Warburton EA, Antoun NM, Huang CL, Carpenter TA, Pickard JD: MR diffusion tensor imaging of white matter tract disruption in stroke at 3 T. Br J Radiol. 2001, 883: 642-647.View ArticleGoogle Scholar
- Maeda T, Ichizaki K, Yura S: Can diffusion tensor imaging predict the functional outcome of supratentorial stroke?. No To Shinkei. 2005, 57: 27-32.PubMedGoogle Scholar
- Yoshioka H, Horikoshi T, Aoki S, Hori M, Ishigame K, Uchida M, Sugita M, Araki T, Kinouchi H: Diffusion tensor tractography predicts motor functional outcome in patients with spontaneous intracerebral hemorrhage. Neurosurgery. 2008, 62: 97-103.View ArticlePubMedGoogle Scholar
- Jang SH, Chang CH, Lee J, Kim CS, Seo JP, Yeo SS: Functional role of the corticoreticular pathway in chronic stroke patients. Stroke. 2013, 44: 1099-1104.View ArticlePubMedGoogle Scholar
- Cho SH, Kim SH, Choi BY, Kang JH, Lee CH, Byun WM, Jang SH: Motor outcome according to diffusion tensor tractography findings in the early stage of intracerebral hemorrhage. Neurosci Lett. 2007, 421: 142-146.View ArticlePubMedGoogle Scholar
- Kusano Y, Seguchi T, Horiuchi T, Kakizawa Y, Kobayashi T, Tanaka Y, Seguchi K, Hongo K: Prediction of functional outcome in acute cerebral hemorrhage using diffusion tensor imaging at 3 t: A prospective study. AJNR Am J Neuroradiol. 2009, 30: 1561-1565.View ArticlePubMedGoogle Scholar
- Davidoff RA: The pyramidal tract. Neurology. 1990, 40: 332-339.View ArticlePubMedGoogle Scholar
- York DH: Review of descending motor pathways involved with transcranial stimulation. Neurosurgery. 1987, 20: 70-73.View ArticlePubMedGoogle Scholar
- Jang SH: The corticospinal tract: A review from the viewpoint of brain rehabilitation. J Rehabil Med. 2013, 46: 193-199.View ArticleGoogle Scholar
- Freund HJ: Premotor area and preparation of movement. Rev Neurol. 1990, 146: 543-547.PubMedGoogle Scholar
- Jang SH: The recovery of walking in stroke patients: A review. Int J Rehab Res Internationale Zeitschrift fur Rehabilitationsforschung Revue internationale de recherches de readaptation. 2010, 33: 285-289.View ArticleGoogle Scholar
- Matsuyama K, Mori F, Nakajima K, Drew T, Aoki M, Mori S: Locomotor role of the corticoreticular-reticulospinal-spinal interneuronal system. Prog Brain Res. 2004, 143: 239-249.View ArticlePubMedGoogle Scholar
- Mendoza JE, Foundas AL: Clinical neuroanatomy: A neurobehavioral approach. 2007, New York/London: Springer, 704-ixGoogle Scholar
- Kumral E, Bayulkem G, Evyapan D: Clinical spectrum of pontine infarction. Clinical-mri correlations. J Neurol. 2002, 249: 1659-1670.View ArticlePubMedGoogle Scholar
- Kim EH, Lee J, Jang SH: Motor outcome prediction using diffusion tensor tractography of the corticospinal tract in large middle cerebral artery territory infarct. NeuroRehabilitation. 2013, 32: 583-590.PubMedGoogle Scholar
- Do KH, Yeo SS, Lee J, Jang SH: Injury of the corticoreticular pathway in patients with proximal weakness following cerebral infarct: Diffusion tensor tractography study. Neurosci Lett. 2013, 546: 21-25.View ArticlePubMedGoogle Scholar
- Kwon YH, Jeoung YJ, Lee J, Son SM, Kim S, Kim C, Jang SH: Predictability of motor outcome according to the time of diffusion tensor imaging in patients with cerebral infarct. Neuroradiology. 2012, 54: 691-697.View ArticlePubMedGoogle Scholar
- Jang SH, Kim SH, Cho SH, Choi BY, Cho YW: Demonstration of motor recovery process in a patient with intracerebral hemorrhage. NeuroRehabilitation. 2007, 22: 141-145.PubMedGoogle Scholar
- Yeo SS, Kim SH, Jang SH: Proximal weakness due to injury of the corticoreticular pathway in a patient with traumatic brain injury. NeuroRehabilitation. 2013, 32: 665-669.PubMedGoogle Scholar
- Yeo SS, Jang SH: Recovery of an injured corticospinal tract and an injured corticoreticular pathway in a patient with intracerebral hemorrhage. NeuroRehabilitation. 2013, 32: 305-309.PubMedGoogle Scholar
- Jung YJ, Jang SH: The fate of injured corticospinal tracts in patients with intracerebral hemorrhage: Diffusion tensor imaging study. AJNR Am J Neuroradiol. 2012, 33: 1775-1778.View ArticlePubMedGoogle Scholar
- Demeurisse G, Demol O, Robaye E: Motor evaluation in vascular hemiplegia. Eur Neurol. 1980, 19: 382-389.View ArticlePubMedGoogle Scholar
- Brunnstrom S: Motor testing procedures in hemiplegia: Based on sequential recovery stages. Phys Ther. 1966, 46: 357-375.PubMedGoogle Scholar
- Holden MK, Gill KM, Magliozzi MR, Nathan J, Piehl-Baker L: Clinical gait assessment in the neurologically impaired. Reliability and meaningfulness. Phys Ther. 1984, 64: 35-40.PubMedGoogle Scholar
- Jang SH: Somatotopic arrangement and location of the corticospinal tract in the brainstem of the human brain. Yonsei Med J. 2011, 52: 553-557.View ArticlePubMedPubMed CentralGoogle Scholar
- Kunimatsu A, Aoki S, Masutani Y, Abe O, Hayashi N, Mori H, Masumoto T, Ohtomo K: The optimal trackability threshold of fractional anisotropy for diffusion tensor tractography of the corticospinal tract. Magn Reson Med Sci. 2004, 3: 11-17.View ArticlePubMedGoogle Scholar
- Kwak R, Kadoya S, Suzuki T: Factors affecting the prognosis in thalamic hemorrhage. Stroke. 1983, 14: 493-500.View ArticlePubMedGoogle Scholar
- Neil JJ: Diffusion imaging concepts for clinicians. J Magn Reson Imaging. 2008, 27: 1-7.View ArticlePubMedGoogle Scholar
- Mori S, Crain BJ, Chacko VP, van Zijl PC: Three-dimensional tracking of axonal projections in the brain by magnetic resonance imaging. Ann Neurol. 1999, 45: 265-269.View ArticlePubMedGoogle Scholar
- Assaf Y, Pasternak O: Diffusion tensor imaging (dti)-based white matter mapping in brain research: A review. J Mol Neurosci. 2008, 34: 51-61.View ArticlePubMedGoogle Scholar
- Lee SK, Kim DI, Kim J, Kim DJ, Kim HD, Kim DS, Mori S: Diffusion-tensor mr imaging and fiber tractography: A new method of describing aberrant fiber connections in developmental cns anomalies. Radiographics. 2005, 25: 53-65. discussion 66–58View ArticlePubMedGoogle Scholar
- Parker GJ, Alexander DC: Probabilistic anatomical connectivity derived from the microscopic persistent angular structure of cerebral tissue. Philos Trans R Soc Lond B Biol Sci. 2005, 360: 893-902.View ArticlePubMedPubMed CentralGoogle Scholar
- Yamada K, Sakai K, Akazawa K, Yuen S, Nishimura T: Mr tractography: A review of its clinical applications. Magn Reson Med Sci. 2009, 8: 165-174.View ArticlePubMedGoogle Scholar
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2377/14/121/prepub
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.