Department of Rehabilitation Medicine, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea.
Corresponding author: Seong Hoon Lim. Department of Rehabilitation Medicine, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon 16247, Korea. Tel: +82-31-249-7650, Fax: +82-31-251-4481, seonghoon@catholic.ac.kr
• Received: November 6, 2015 • Accepted: March 7, 2016
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
To investigate the effects of specific brain lesions on prognosis and recovery of post-stroke aphasia, and to assess the characteristic pattern of recovery.
Methods
Total of 15 subjects with first-ever, left hemisphere stroke, who were right handed, and who completed language assessment using the Korean version of the Western Aphasia Battery (K-WAB) at least twice during the subacute and chronic stages of stroke, were included. The brain lesions of the participants were evaluated using MRI-cron, SPM8, and Talairach Daemon software.
Results
Subtraction of the lesion overlap map of the participants who showed more than 30% improvement in the aphasia quotient (AQ) by the time of their chronic stage (n=9) from the lesion overlap map of those who did not show more than 30% improvement in the AQ (n=6) revealed a strong relationship with Broca's area, inferior prefrontal gyrus, premotor cortex, and a less strong relationship with Wernicke's area and superior and middle temporal gyri. The culprit lesion related to poor prognosis, after grouping the subjects according to their AQ score in the chronic stage (a cut score of 50), revealed a strong relationship with Broca's area, superior temporal gyrus, and a less strong relationship with Wernicke's area, prefrontal cortex, and inferior frontal gyrus.
Conclusion
Brain lesions in the Broca's area, inferior prefrontal gyrus, and premotor cortex may be related to slow recovery of aphasia in patients with left hemisphere stroke. Furthermore, involvement of Broca's area and superior temporal gyrus may be associated with poor prognosis of post-stroke aphasia.
Aphasia is one of the most common post-stroke disabilities [1], and its incidence following first-ever stroke had been reported to be 30%–38% in hospitalized patients [2]. Traditionally, several areas of the brain are known to be responsible for language, such as Broca's and Wernicke's areas, and the transcortical and subcortical pathways which connect them [3]. However, lesions in other areas can also manifest features of aphasia, and many studies have been investigating the further brain lesions related to language network [45]. Advances in neuroimaging such as voxelwise lesion-behavior mapping (VLBM) and diffusion tensor imaging (DTI) have allowed us to locate these lesions [67], and these insights might be helpful in understanding the effects of the lesions; thus, enabling greater accuracy of clinical diagnosis and better management.
The aim of this study is to investigate the effect of the specific brain lesion site on prognosis and recovery of aphasia, along with assessment of the characteristic recovery pattern of subacute and chronic post-stroke aphasia.
MATERIALS AND METHODS
Study design and participants
This is a retrospective study of patients with aphasia resulting from acute stroke, who were admitted to the Department of Rehabilitation Medicine of St. Vincent's Hospital from January 2009 to December 2014. The inclusion criteria were as follows: (1) first-ever stroke, (2) only one left hemisphere lesion, either ischemic or hemorrhagic, confirmed by magnetic resonance imaging (MRI), (3) right handedness, and (4) completion of language assessment using the Korean version of the Western Aphasia Battery (K-WAB) at least twice, first assessment within 3 months post-onset of stroke and the other assessment(s) at least 3 months after the initial assessment. No restriction was placed on the type or severity of the aphasia, and subjects were excluded if they had any other functional or structural brain disorder. Of the 372 individuals, only 15 qualified for the study.
All subjects were investigated with respect to their demographic data and the results of their language assessments were collected. For precise localization of their brain lesions, high resolution 1.5T anatomical MRI scans with a 5-mm slice thickness were analyzed using MRIcron, SPM8, and Talairach Daemon software [8].
The study was approved by the Ethics Committee of The Catholic University of Korea.
Language test
All participants were examined using the validated K-WAB, and the results were subjected to analysis only when aphasia was caused by first-ever stroke at the time of admission.
The WAB assessment is composed of four subtests of fluency, comprehension, repetition, and naming. The severity of aphasia is quantified using aphasia quotient (AQ; range, 0–100), which was calculated using the Kertesz's formula [9]: (fluency score+comprehension score/20 + repetition score/10 + naming score/10)×2.
Subjects included in the study completed their initial WAB assessment within 3 months of stroke onset, and the follow-up test was completed at least 3 months after the initial assessment. Changes in AQ and the four subsets of WAB were compared and evaluated to determine their significance.
Lesion tracing and analysis procedures
Lesion size was calculated using the Picture Achieved Communication System (PACS; Marotech, Seoul, Korea), and the absolute lesion size (cm3) was determined by multiplying the sum of all lesion areas in each plane by the slice thickness.
Localization of the brain lesions was conducted using MRIcron. The origin of the image (0, 0, 0 mm coordinates) was reoriented to locate as close as possible to the anterior commissure. VOI images of each patient were traced using MRIcron software (http://www.mricro.com/mricron), and then the tracings were coregistered to the Montreal Neurological Institute brain templates [10]. In order to deduce the lesion overlap maps, the first step is to roughly align the T1 image onto a standard space. This will approximately locate the anterior commissure, which will aid subsequent normalization. The next step is to coregister the T2 scan to the space of the T1 scan. The T2 image will then be moved and rotated until it is closely aligned with the T1 scan. The final step is to align the T1 image in the stereotaxic space. This series of processes was performed in combination with SPM8 unified segmentation and normalization. The Talairach Daemon software (http://www.talairach.org) was used to identify relevant anatomic structures implicated in the analysis [11].
Statistical analysis
Statistical analysis was performed using the SPSS software ver. 20.0 (IBM, Armonk, NY, USA). All continuous variables were analyzed with non-parametric testing using Mann-Whitney test, due to non-normal distribution. All tests were two-tailed, and statistical significance was accepted for p-values <0.05.
RESULTS
A total of 15 patients were included in the study. Among them, there were 7 males and 8 females, with an average age of 55.27±18.07 years, ranging from 22 to 80 years. Patients underwent their initial K-WAB at a mean time period of 38.8±21.24 days (range, 15–90 days) after the onset of stroke, and the follow-up K-WAB at a mean time period of 185.8±69.70 days (range, 109–313 days) after the onset of stroke (Table 1). The average interval between the initial and the subsequent K-WAB assessments was 147.0±56.10 days (range, 94–257 days). The follow-up K-WAB results showed statistically significant improvement in three of the four subtests of K-WAB, including fluency, comprehension, and repetition. The most prominent improvement was noted in the comprehension aspect (Table 2).
The lesion overlap map for all 15 participants showed extensive coverage over the left hemisphere supplied by the middle cerebral artery (Fig. 1). The colors represent the frequency of overlapping.
Participants who showed more than 30% improvement in AQ by the time of the follow-up K-WAB (n=9) and those who did not show more than 30% improvement in AQ (n=6) were separated (Table 3). There was no significant difference in age and brain lesion volume categories between the two groups (p=0.328 and p=0.181, respectively). Subtraction of the lesion overlap map of the previous group from that of the latter group revealed a strong relationship with Broca's area, inferior prefrontal gyrus, and premotor cortex, and a less strong relationship with Wernicke's area and superior and middle temporal gyri in the left hemisphere (Fig. 2).
Then, the participants whose AQ in the follow-up K-WAB was equal to or higher than 50 (n=6) and those whose AQ in the follow-up K-WAB was less than 50 (n=9) were separated (Table 4). There was no significant difference in age and brain lesion volume categories between the two groups (p=0.607 and p=0.689, respectively). Subtraction of the lesion overlap map of the previous group from that of the latter group revealed a strong relationship with Broca's area and superior temporal gyrus, and a less strong relationship with Wernicke's area, prefrontal cortex, and inferior frontal gyrus in the left hemisphere (Fig. 3).
DISCUSSION
Our results indicate that involvement of Broca's area, the motor center of speech, and superior temporal gyrus, the comprehension center, is related to poor long-term outcome of aphasia in left hemisphere stroke [12]. Meanwhile, involvement of inferior prefrontal gyrus, which plays an important role in semantic processing [1314], and premotor cortex, which is associated with apraxia of speech, may not determine the prognosis of aphasia, but impedes recovery of aphasia [15]. Also, Broca's area is not only associated with poor prognosis, but also with rate or recovery of aphasia. Clinically, treatment with a focus on recovering semantic language or improving apraxia of speech can be attempted for optimal recovery in aphasic patients with damage to the inferior prefrontal gyrus or premotor cortex. Further studies involving such treatment modalities are promising, and they may be helpful in understanding the interrelationship between longterm outcome and recovery rate or pattern of aphasia.
Recent studies have revealed that impairment in many other brain sites beyond the classical Broca's or Wernicke's areas may be closely related to aphasia [16]. With respect to the role of premotor cortex in the language pathway, many recent studies have reported the involvement of motor areas in speech perception [17]. Left premotor cortex is involved in transforming perceived sounds into motor representations, with aid of bilateral superior temporal cortex [17]. In addition, in rhesus, the ventrolateral prefrontal cortex is thought to be part of a circuit involved in representing vocalizations and other auditory objects [18]. In the study by Eickhoff et al. [19], the final output of speech production is sent to the premotor cortex, and it converts movement patterns into muscle-specific commands. Furthermore, studies using perfusion-weighted imaging, structural MRI analysis, and functional imaging with FDG-PET have shown that damage or hypoperfusion in the inferior frontal gyrus and lateral premotor cortex strongly predicts apraxia of speech [20].
However, improved neuroimaging methods and analysis prove that both functional and structural connectivity within the speech network differ in persons [20]. Since aphasia is a multi-dimensional disorder in which patient profiles reflect variation along multiple behaviors, it may be mandatory to approach aphasia under multiple core factors such as phonology, semantics, and cognition [6]. With the use of principle components analysis and voxelbased lesion-symptom mapping (VLSM), Butler et al. [6] proved that the phonological aspect of post-stroke aphasia was uniquely correlated with damage to the left mid to posterior superior temporal gyrus, middle temporal gyrus, superior temporal sulcus, Heschl's gyrus, and arcuate fasciculus component of the dorsal language route. Furthermore, the semantic aspect of aphasia was uniquely related to the left anterior middle temporal gyrus, and the ventral language route.
In our study, only 12 of the 15 participants had been tested for cognitive function using the Mini-Mental State Examination (MMSE) within the first 2 months after the onset of stroke, and follow-up MMSE scores had been recorded after this period in only 7 of these patients. Due to the small number of participants and incomplete data, we were unable to draw a conclusion on the relationship between post-stroke aphasia and cognitive function. Nonetheless, it is well-known that cognitive impairment often co-exists with aphasia in post-stroke patients, limiting the efficacy of rehabilitation of language. According to Lee and Pyun [21], attention and working memory ability were significantly worse in aphasic patients, and another study showed the severity of aphasia was significantly correlated with them [22]. In addition, spoken communication is susceptible to orientation, spatial perception, and visual perception, which are also strongly connected with improvement from aphasia, especially in naming and comprehension functions [23].
Several previous studies noted that not only the location, but also the size of the brain lesion plays a role in determining the prognosis of aphasia in stroke patients [2425]. However, in our study, there was no significant difference in the volume of brain lesions between the groups (Tables 3, 4). Other studies have reported that the location of the brain lesion is more crucial than the extent or size of the lesion [26]. Among them, many studies attest that the recovery of aphasia is inversely related to the size; thus, reinforcing the importance of preservation of the left superior temporal gyrus and basal ganglia [27].
With respect to interval change of language function, the follow-up K-WAB results in the subacute or chronic stage of stroke showed statistically significant improvement in three of the four subtests of K-WAB, including fluency, comprehension, and repetition. The most prominent improvement was noted in the comprehension aspect. Smania et al. [28] reported a case in which the authors studied the long-term outcome of language in a patient with global aphasia after a large ischemic lesion in the left middle cerebral artery territory. Several tests including the Milan Language Examination, the Token Test, the Raven Test, and tests for apraxia were repeated, and the patient's first year after stroke was characterized by recovery of verbal comprehension and word repetition, the next 2 years were characterized by emergence of naming and reading, and the next 20 years were characterized by a progressive improvement in the above areas and emergence of spontaneous speech. The rate of improvement estimated at 1 year was the highest in the comprehension aspect (70%), followed by the repetition aspect (50%). Krishnan et al. [29] studied 12 first-ever hemorrhagic stroke-aphasic subjects, and all participants with non-global aphasia showed preserved comprehension skills. Those with initial global aphasia exhibited recovery of comprehension skills, thus evolving to Broca's aphasia at the follow-up evaluation. In their study, the comprehension skills of the subjects were relatively spared, and when affected, they showed faster recovery when compared to the other aspects.
The main limitation of our study was the small number of patients. Recovery pattern of aphasia may also be affected by the type of aphasia; however, our study has a small sample size to investigate this aspect. Further studies involving larger number of subjects are warranted. In addition, other factors which may influence language function such as the cognitive or psychological aspect of the patients should be evaluated in more depth. Last, but not the least, assessment of not only the affected or impaired lesions, but also the structural or functional connectivity between the lesions may be of great importance, probably by incorporating functional MRI or DTI.
According to our findings, involvement of Broca's area, inferior prefrontal gyrus, and premotor cortex might be related to the slow recovery rate of aphasia in left hemisphere stroke. Furthermore, involvement of Broca's area and superior temporal gyrus might be related to poor long-term outcome of aphasia in left hemisphere stroke. These results could be useful for planning aphasia rehabilitation and for further understanding the prognosis of post-stroke aphasia.
CONFLICT OF INTEREST:
CONFLICT OF INTEREST: No potential conflict of interest relevant to this article was reported.
REFERENCES
1. Hoffmann M, Chen R. The spectrum of aphasia subtypes and etiology in subacute stroke. J Stroke Cerebrovasc Dis 2013;22:1385-1392.
2. Berthier ML, Pulvermüller F, Dávila G, Casares NG, Gutiérrez A. Drug therapy of post-stroke aphasia: a review of current evidence. Neuropsychol Rev 2011;21:302-317.
3. Charidimou A, Kasselimis D, Varkanitsa M, Selai C, Potagas C, Evdokimidis I. Why is it difficult to predict language impairment and outcome in patients with aphasia after stroke. J Clin Neurol 2014;10:75-83.
7. Saur D, Hartwigsen G. Neurobiology of language recovery after stroke: lessons from neuroimaging studies. Arch Phys Med Rehabil 2012;93(1 Suppl): S15-S25.
8. Lee KB, Kim JS, Hong BY, Kim YD, Hwang BY, Lim SH. The motor recovery related with brain lesion in patients with intracranial hemorrhage. Behav Neurol 2015;2015:258161.
10. Brett M, Leff AP, Rorden C, Ashburner J. Spatial normalization of brain images with focal lesions using cost function masking. Neuroimage 2001;14:486-500.
12. Friederici AD, Ruschemeyer SA, Hahne A, Fiebach CJ. The role of left inferior frontal and superior temporal cortex in sentence comprehension: localizing syntactic and semantic processes. Cereb Cortex 2003;13:170-177.
14. Poldrack RA, Wagner AD, Prull MW, Desmond JE, Glover GH, Gabrieli JD. Functional specialization for semantic and phonological processing in the left inferior prefrontal cortex. Neuroimage 1999;10:15-35.
15. Itabashi R, Nishio Y, Kataoka Y, Yazawa Y, Furui E, Matsuda M, et al. Damage to the left precentral gyrus is associated with apraxia of speech in acute stroke. Stroke 2016;47:31-36.
18. Cohen YE, Theunissen F, Russ BE, Gill P. Acoustic features of rhesus vocalizations and their representation in the ventrolateral prefrontal cortex. J Neurophysiol 2007;97:1470-1484.
19. Eickhoff SB, Heim S, Zilles K, Amunts K. A systems perspective on the effective connectivity of overt speech production. Philos Trans A Math Phys Eng Sci 2009;367:2399-2421.
20. Ballard KJ, Tourville JA, Robin DA. Behavioral, computational, and neuroimaging studies of acquired apraxia of speech. Front Hum Neurosci 2014;8:892.
22. Seniow J, Litwin M, Lesniak M. The relationship between non-linguistic cognitive deficits and language recovery in patients with aphasia. J Neurol Sci 2009;283:91-94.
23. Yu ZZ, Jiang SJ, Bi S, Li J, Lei D, Sun LL. Relationship between linguistic functions and cognitive functions in a clinical study of Chinese patients with post-stroke aphasia. Chin Med J (Engl) 2013;126:1252-1256.
24. Kertesz A, Harlock W, Coates R. Computer tomographic localization, lesion size, and prognosis in aphasia and nonverbal impairment. Brain Lang 1979;8:34-50.
27. Heiss WD, Thiel A, Kessler J, Herholz K. Disturbance and recovery of language function: correlates in PET activation studies. Neuroimage 2003;20(Suppl 1): S42-S49.
28. Smania N, Gandolfi M, Aglioti SM, Girardi P, Fiaschi A, Girardi F. How long is the recovery of global aphasia? Twenty-five years of follow-up in a patient with left hemisphere stroke. Neurorehabil Neural Repair 2010;24:871-875.
Lesion overlap map for all participants (n=15). Color spectrum based on overlapping proportion (%).
Fig. 2
Subtraction of overlay of participants with more than 30% AQ improvement (n=9) from that of those with less than 30% AQ improvement (n=6). Color spectrum based on overlapping proportion (%). AQ, aphasia quotient.
Fig. 3
Subtraction of overlay of participants with follow-up AQ more than 50 (n=6) from that of those with follow-up AQ less than 50 (n=9). Color spectrum based on overlapping proportion (%). AQ, aphasia quotient.
Table 1
Baseline characteristics and brain lesions of the subjects
K-WAB, Korean version of the Western Aphasia Battery; AQ, aphasia quotient; MCA, middle cerebral artery; ICH, intracerebral hemorrhage.
Table 2
Results of the language evaluations (K-WAB)
Values are given in median (range).
Maximum scores: aphasia quotient out of 100; fluency, 20; comprehension, 200; repetition, 100; and naming, 100.
K-WAB, Korean version of the Western Aphasia Battery.
a)Mann-Whitney test.
Table 3
Group characteristics depending on the improvement in AQ
Values are presented as number or mean±standard deviation.
AQ, aphasia quotient.
a)Mann-Whitney test.
Table 4
Group characteristics depending on the follow-up AQ
Values are presented as number or mean±standard deviation.
AQ, aphasia quotient.
a)Mann-Whitney test.
Figure & Data
References
Citations
Citations to this article as recorded by
Language function improvement and cortical activity alteration using scalp acupuncture coupled with speech-language training in post-stroke aphasia: A randomised controlled study Bingbing Lin, Jinglei Ni, Xiao Xiong, Lanlan Zhang, Jian Song, Mengxue Wang, Linsong Chai, Yunshi Huang, Jia Huang Complementary Therapies in Medicine.2025; 89: 103137. CrossRef
Minimal important change for the aphasia quotient of the Chinese Western Aphasia Battery Yuqian ZHANG, Changhui SUN, Shan XIE, Zhefan WU, Jing LI, Chan CHEN, Yulong BAI European Journal of Physical and Rehabilitation Medicine.2025;[Epub] CrossRef
The frequency and characteristics of saccadic dysmetria in isolated cerebellar infarction Sohyeon Kim, Hyun Ah Kim, Hyung Lee Neurological Sciences.2023; 44(6): 2097. CrossRef
Features of EEG microstate analysis in post-stroke aphasia SA Gulyaev, LM Khanukhova, AA Garmash Medicine of Extreme Situations.2023;[Epub] CrossRef
Factors predicting long-term recovery from post-stroke aphasia Denise Y. Harvey, Shreya Parchure, Roy H. Hamilton Aphasiology.2022; 36(11): 1351. CrossRef
Effect of Repetitive Transcranial Magnetic Stimulation on Post-stroke Non-fluent Aphasia in Relation with Broca's Area Eun-Ho Yu, Ji Hong Min, Yong-Il Shin, Hyun-Yoon Ko, Sung-Hwa Ko Brain & Neurorehabilitation.2021;[Epub] CrossRef
Single Word Repetition Predicts Long-Term Outcome of Aphasia Caused by an Ischemic Stroke Miguel Tábuas-Pereira, José Beato-Coelho, Joana Ribeiro, Ana Rita Nogueira, Luis Cruz, Fernando Silva, João Sargento-Freitas, Gustavo Cordeiro, Isabel Santana Journal of Stroke and Cerebrovascular Diseases.2020; 29(2): 104566. CrossRef
Clinical risk factors for post-stroke urinary incontinence during rehabilitation Nataša Bizovičar, Brigita Mali, Nika Goljar International Journal of Rehabilitation Research.2020; 43(4): 310. CrossRef
Predictive role of subcomponents of the left arcuate fasciculus in prognosis of aphasia after stroke Qiwei Yu, Hong Wang, Shuqing Li, Yanhong Dai Medicine.2019; 98(23): e15775. CrossRef
Leukoaraiosis Is Associated With a Decline in Language Abilities in Chronic Aphasia Alexandra Basilakos, Brielle C. Stark, Lisa Johnson, Chris Rorden, Grigori Yourganov, Leonardo Bonilha, Julius Fridriksson Neurorehabilitation and Neural Repair.2019; 33(9): 718. CrossRef
Association of Lesion Location With Long-Term Recovery in Post-stroke Aphasia and Language Deficits Bomi Sul, Kyoung Bo Lee, Bo Young Hong, Joon Sung Kim, Jaewon Kim, Woo Seop Hwang, Seong Hoon Lim Frontiers in Neurology.2019;[Epub] CrossRef
Regression of Poststroke Aphasia and Concomitant Nonspeech Syndromes Due to Courses of Restorative Therapy Including Intensive Speech Therapy V. M. Shklovskij, V. V. Alferova, E. G. Ivanova, L. A. Mayorova, A. G. Petrushevsky, G. V. Ivanov, S. V. Kuptsova, E. A. Kondrateva, A. B. Guekht Neuroscience and Behavioral Physiology.2019; 49(9): 1184. CrossRef
Changes in Language Function and Recovery-Related Prognostic Factors in First-Ever Left Hemispheric Ischemic Stroke Kyung Ah Kim, Jung Soo Lee, Won Hyuk Chang, Deog Young Kim, Yong-Il Shin, Soo-Yeon Kim, Young Taek Kim, Sung Hyun Kang, Ji Yoo Choi, Yun-Hee Kim Annals of Rehabilitation Medicine.2019; 43(6): 625. CrossRef
Effects of different frequencies of repetitive transcranial magnetic stimulation in stroke patients with non-fluent aphasia: a randomized, sham-controlled study Xue-yan Hu, Tong Zhang, Gary B. Rajah, Christopher Stone, Li-xu Liu, Jing-jie He, Lei Shan, Ling-yu Yang, Ping Liu, Fei Gao, Yu-qi Yang, Xiao-li Wu, Chang-qing Ye, Yu-dong Chen Neurological Research.2018; 40(6): 459. CrossRef
The prognosis for post-stroke aphasia V. V. Alferova, V. M. Shklovskij, E. G. Ivanova, G. V. Ivanov, L. A. Mayorova, A. G. Petrushevsky, S. V. Kuptsova, A. B. Guekht Zhurnal nevrologii i psikhiatrii im. S.S. Korsakova.2018; 118(4): 20. CrossRef
Critical brain regions related to post-stroke aphasia severity identified by early diffusion imaging are not the same when predicting short- and long-term outcome Chiara Zavanone, Yves Samson, Céline Arbizu, Sophie Dupont, Didier Dormont, Charlotte Rosso Brain and Language.2018; 186: 1. CrossRef
Regression of post-stroke aphasia and associated non-speech syndromes caused by a course of restorative treatment including intensive speech therapy V. M. Shklovskij, V. V. Alferova, E. G. Ivanova, L. A. Mayorova, A. G. Petrushevsky, G. V. Ivanov, S. V. Kuptsova, E. A. Kondrateva, A. B. Guekht Zhurnal nevrologii i psikhiatrii im. S.S. Korsakova.2018; 118(11): 20. CrossRef
Brain lesions affecting gait recovery in stroke patients Kyoung Bo Lee, Joon Sung Kim, Bo Young Hong, Bomi Sul, Seojin Song, Won Jin Sung, Byong Yong Hwang, Seong Hoon Lim Brain and Behavior.2017;[Epub] CrossRef
The Prognosis and Recovery of Aphasia Related to Stroke Lesion
Fig. 1 Lesion overlap map for all participants (n=15). Color spectrum based on overlapping proportion (%).
Fig. 2 Subtraction of overlay of participants with more than 30% AQ improvement (n=9) from that of those with less than 30% AQ improvement (n=6). Color spectrum based on overlapping proportion (%). AQ, aphasia quotient.
Fig. 3 Subtraction of overlay of participants with follow-up AQ more than 50 (n=6) from that of those with follow-up AQ less than 50 (n=9). Color spectrum based on overlapping proportion (%). AQ, aphasia quotient.
Fig. 1
Fig. 2
Fig. 3
The Prognosis and Recovery of Aphasia Related to Stroke Lesion
Baseline characteristics and brain lesions of the subjects
K-WAB, Korean version of the Western Aphasia Battery; AQ, aphasia quotient; MCA, middle cerebral artery; ICH, intracerebral hemorrhage.
Results of the language evaluations (K-WAB)
Values are given in median (range).
Maximum scores: aphasia quotient out of 100; fluency, 20; comprehension, 200; repetition, 100; and naming, 100.
K-WAB, Korean version of the Western Aphasia Battery.
a)Mann-Whitney test.
Group characteristics depending on the improvement in AQ
Values are presented as number or mean±standard deviation.
AQ, aphasia quotient.
a)Mann-Whitney test.
Group characteristics depending on the follow-up AQ
Values are presented as number or mean±standard deviation.
AQ, aphasia quotient.
a)Mann-Whitney test.
Table 1 Baseline characteristics and brain lesions of the subjects
K-WAB, Korean version of the Western Aphasia Battery; AQ, aphasia quotient; MCA, middle cerebral artery; ICH, intracerebral hemorrhage.
Table 2 Results of the language evaluations (K-WAB)
Values are given in median (range).
Maximum scores: aphasia quotient out of 100; fluency, 20; comprehension, 200; repetition, 100; and naming, 100.
K-WAB, Korean version of the Western Aphasia Battery.
a)Mann-Whitney test.
Table 3 Group characteristics depending on the improvement in AQ
Values are presented as number or mean±standard deviation.
AQ, aphasia quotient.
a)Mann-Whitney test.
Table 4 Group characteristics depending on the follow-up AQ
Values are presented as number or mean±standard deviation.
, Joon Sung Kim, MD, PhD
