Neurosurg. R e v . 17 (1994) 299-304 C r o s s e d aphasia. A n u p d a t e Luciano Mastronardi, Luigi Ferrante, Alberto Maleci, Fabrizio Puzzilli, Pierpaolo Lunardi, and Giuseppe Schettini Department of Neurological Sciences, Neurosurgery, University of Rome "La Sapienza", Italy Abstract The aim of this article is to present an update of a rare but interesting problem: "crossed aphasia". This term indicates the presence of aphasia after tmilateral cerebral lesion of the hemisphere ipsilateral to the patient's domin~mt hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and nemophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder. Keywerds: Aphasia, crossed aphasia, hemispheric dominance, language disorders. Thus, a reliable diagnosis of crossed aphasia should be based on: A) neuropsychological assessment of dominant hemisphere; B) lack of familiality for left-handedness; C) lack of lesions on left hemisphere, proved by CT or MRI or by pathological examination [18, 25, 41]. Crossed aphasia can be a source of detailed information about the functional and anatomical organization of the cognitive system [8]. Reporting two cases of crossed aphasia in two dextral subjects, we analyze the clinical aspects of this particular speech disorder, with the aim of examining the possible neuro-anatomical and neurophysiological correlations. 1 Introduction The term "crossed aphasia", introduced by BRAMWELL in 1899 [9], indicates the presence of aphasia after unilateral cerebral involvement of the hemisphere ipsilateral to the patient's dominant hand. BRAMWELL [9] maintained that crossed aphasia in a dextral could verify only in a "genetically" left-handed man, who has become right-handed as result of practice (constitutional sinistrality), JACKSON [26], however, affirmed that not in every case of aphasia associated with left hemiplegia was the patient indisputably lefthanded. Progressively the concept of crossed aphasia has been confined to aphasia accompanying lesions of right hemisphere in surely righthanded patients [5], without familiality for lefthandedness, even if the left hemisphere seems to be dominant for language in both right- and lefthanded subjects [17]. 9 1994by Walter de Gruyter& Co. Berlin. New York 2 Case reports Case 1. M.C., 69-year-old, monolingual, righthanded man (tested by the Edinburgh Handedness Inventory), without family history of left-handedness. Since three months before admission, he had suffered from motor Jacksonian seizures on left-hemisoma. A cerebral CT scan showed an intraparenchymal, homogeneous, right-sided temporal-parietal tumor, with iITegular contrast enhancement (Figure 1). A subtotal removal of tumor was performed and the neoplasm pathological examination showed a WHO Grade 3 astrocytoma [9]. Few weeks later the patient underwent radiotherapy and chemotherapy, with marked reduction of the deep tumoral residue. Six months after operation he again suffered Jacksonian seizures on the left limbs, followed by 300 Figure 1. Cerebral CT scan: right temporal-parietal tumor (high-grade astrocytoma), with irregular contrast enhancement. a transient motor disphasia. A cerebral CT scan showed a growth of residual tumor, with posterior and deep extension; the left hemisphere appeared undamaged. A further radio- and chemotherapy cycle was performed and seizures were controlled with drugs. About one year after operation, the patient began to present a progressive left sided hemiparesis and expressive disphasia: he formulated sentences with no more than 6 - 8 words, committing about 50% of syntactic and semantic errors, with acceptable phonetic expression. Paraphasias, neologisms and persevering errors were frequent. Verbal learning, short sentence repetition and memory were impaired. A slight dysgraphia was also present; comprehension of read sentences was preserved. Visuo-spatial and calculation abilities were moderately impaired. Mastronardi et al., Crossed aphasia A cerebral CT scan performed sixteen months later because of reappearance of seizures revealed a recurrence of the tumor, with deep extension (Figure 2). A subtotal excision of the mass was performed, leaving the deepest part of tumor in situ, in relation to the slight preoperative neurological picture. Histological examination showed a malignant transformation of neoplasm (WHO Grade 4 glioma) [39]. Three days after operation the patient presented progressive left hemiparesis and mixed disphasia, caused by a severe edematous reaction. She formulated only short sentences, with frequent syntactic, phonemic and semantic errors; paraphasias were also very common. The ability to comprehend verbal and written orders was partially impaired, with severe agraphia. Visuo-spatial, calculation, praxis and constructional abilities were moderately impaired. With the help of cortisonics and osmotics the clinical symptoms disappeared. Fifteen days after operation intraarterial chemotherapy (Carboplatin 600 mg/m 2 in right common carotid artery) was attempted: 10 minutes after the onset of infusion severe left hemiparesis appeared, accompained by complete aphasia. The injection of radioopaque contrast medium revealed a marked vasospasm of the right middle cerebral artery, forcing us to interrupt the procedure. A few hours later neurological deficits improved, hemiparesis disappearing in 48 hours and aphasia in one week (the verbal expression was the last to recover). Four months later the patient presented an acute A cerebral M R / s h o w e d a further increase of the dimensions of tumor and the appearance of a small right frontal mass; no lesions were present on the left hemisphere. After a further chemotherapy circle the neurological conditions remain substantially unchanged. The patients died few months later for progression of tumor. Case 2. M.M., 45-year-old, monolingual righthanded woman (Edinburgh Handedness Inventory), without family history of left-handedness. Six years ago she was operated on for a right temporal WHO Grade 2 fibrillary astrocytoma [39] and subsequently treated with radiotherapy. Figure 2. Cerebral CT scan: recurrence of a right temporal glioma, with deep extension (sixteen months later the first operation). Neurosurg. Re~ 17 (1994) Mastronardi et al., Crossed aphasia and severe deterioration of neurological condition with drowsiness, left hemiparesis, and global aphasia. A cerebral CT scan showed a deep recurrence of tumor, without involvement of left hemisphere. The relatives refused the hospitalization and three weeks later the woman died. 3 Discussion The incidence of crossed aphasia in monotingual subjects after unilateral cerebral lesion is rather uncommon, ranging from 0.38% to 2% of all dextral aphasics [2, 6, 21, 24, 32, 38, 41, 49], and extremely rare in children [17]. Even if some authors reported a higher incidence (4.6%-15%) [20, 29, 42], these differences probably express a lack of pathologic confirmation of the location of lesions as well as different criteria of evaluation [44]. The incidence of crossed aphasia seems to be higher in multiracial [4] and in bi- or multilingual populations [20, 29], expecially in those bilingual people whose language is not written [29], the most affected people seeming to be the Indians [16]. Even if some authors maintain that the incidence of crossed aphasia is the same in multi- and mono-linguals [16, 23], KARANTH et al. [20] report a clear difference between the two groups [25% versus zero, respectively), supporting that multilingualism could result from a bilateral representation of language [1, 33, 46]. Moreover, the incidence seems to be higher in lefthanded people (from 25% to 33%) [20, 21, 42], perhaps because of more than two thirds of these people have left-hemisphere dominance for language [17]. Some authors [3, 12, 45, 47] describe crossed aphasia as a generally non-fluent speech disorder, whereas others [25] observe that these patients are frequently fluent. Of 26 crossed aphasics reviewed by FAGLIA et al. [18] 10 had Broca's, 6 Wemicke's, 1 global, 1 transcortical sensory, and 1 mixed transcortical aphasia, whereas 4 were not clearly classifiable. In some cases there was not the same involvement of the spoken and the written language, suggesting that a possible dissociation of cognitive disturbances were present (visuo-spatial disorders and left spatial neglect), whereas apraxia was less frequent [18]. In the cases reviewed by ALEXANDER et al. [2] ideomotor apraxia was present in 11 of 24 cases, whereas Neurosarg. Rev. 17 (1994) 301 14 of 30 had visuo-spatial impain'nent. Therefore, in about 50% of patients the right hemisphere controled both visuo-spatial functions and language [2, 18]. Limb praxis seems to be more strongly related to handedness than to language, being spared in about 2/3 of crossed aphasics, whereas buccofacial praxis seems to be more closely related to language [2]. Phonological and semantic levels of language could be lateralized differently, supporting the concept of dissociation of functions [2, 8]. In the case reported by NAGARAJA et al. [32] the presence of Gerstmann's syndrome seems to be indicative of a complete cross-over of hemispheric functions, even if the lack of apraxia suggests that praxis is controlled by the left hemisphere. On the basis of several neuroanatomical, neurophysiological, and clinical discordances some authors [7, 41] suggested that there may be more than one "crossed aphasia" syndrome. In 23 cases reviewed by ALEXANDER et al. [2], 22 had an aphasia profile typical of intrahemispheric localization. In these cases the aphasic profile might be considered a "mirror image" [2, 25, 41], since the language centers should be localized on the non-dominant hemisphere, without lateralization of other functions ("crossed aphasia type 1"). In 12 cases the aphasia was fluent, in 11 with jargon-agraphia too, despite suprasylvian, prerolandic, or perirolandic injuries [2]. These 12 patients had an "anomalous" aphasia pattern [2, 41 ], recognizable as the "crossed aphasia type 2". In type 1 in which all language seems to be lateralized on right hemisphere, the injury is generally severe, the recovery is usually slow and incomplete, and writing and reading are equally affected [2, 6, 15, 40, 44, 48]. The possible presence of Gerstmann's syndrome [32] would indicate the complete cross-over of parietal functions [28]. In type 2, among which we could include our two cases, aphasia is generally slight and transient, speech and writing are differently affected, praxis and other dominant parietal lobe functions are rarely impaired [2, 22, 41, 47, 49]. This dissociated lateralization of cerebral functions should support the hypothesis of anomalous hemispheric dominance [30], with independent lateralization of language, praxis, and visuo-spa- 302 tial functions. In "anomalous" crossed aphasia the lesion of the right central perirolandic regions could have a role in the phonemic alteration of language, accounting for the unexpected fluent conduction of patients who frequently present phonemic substitution in spoken and written language [2, 17]. Analyzing short-term memory in relation to sentence comprehension in a crossed aphasic, BERNDT et al. [8] affirmed that in righthanded people a close left hemisphere representation of auditory and phonological processing could exist, whereas the right hemisphere could be involved in semantic and lexical analysis. Therefore, it is possible that the corpus callosum works, at least in some subjects, as a "phonological transformer" of visual and auditory informations [23], also explaining the possible appearance of mutism as consequence of callosotomy [43]. The site of lesions causing crossed aphasia is variable and often in disagree with the clinical picture. The damage might be cortical, subcortical (as in our two cases) or both [18], against the hypothesis of a preferred right basal ganglia involvement [7, 15]. There would be no relationships between the crossed aphasia and the pattern of cerebral asymmetries [25], even if we have only a few CT and MRI information. SPECT and PET studies can be undoubtely useful, revealing rCBF and metabolism of involved right cortical regions [34, 41]. With the help of the PET, RArCHLE [36] identified cerebral areas active when hearing words different from those when seeing words, and again from those areas concerned with the motor output of speaking the words and finally from those involved in generating the meaning of words. Viewing and hearing words areas were identified by PET in the motor cortex over the sylvian cortex (supplementary motor area) and in the cerebellum: during the generation of a word the areas of greatest activity were the left frontal cortex, the anterior circulate cortex and the right cerebellum [36]. Therefore, the cognitive implications of cerebellar hemispheres are profound, expecially when it comes to learning new tasks [36]. Mastronardi et al., Crossed aphasia Crossed aphasia has been attributed to ambilaterality, familial sinistrality, earlier brain damage, epilepsy, bilateral representation of language [2, 11, 18, 27, 35, 47, 49], as well as partial or complete cross-over of left hemisphere functions to the right side [28]. According to some authors [3, 43] crossed aphasia could be similar to aphasia observed in children in whom language dominance is not yet firmly established. Others [13, 31, 37] support the hypothesis of a weak correlation between handedness and speech lateralization (also supported by disphasia evocation after unilateral non-dominant electroconvulsive therapy), stressing the importance of the sodium amytal test in determining the hemisphere responsible for language [13, 31]. More recently, JOANNETTEet al. [27] proposed several etiopathogenetic hypotheses to explain crossed aphasia: anatomical aberration, genetic factors, arrest of the trial of lateralization, early functional reorganization after a brain damage during childhood, essential functional aberration, and lesion of subcortical gray matter, even if none seems to be fully satisfactory [27]. To these factors we might add the possible role placed by the congenital deafness (or decreased hearing) in the right ear during the hemispherical functional specialization [35]. In spite of the complex mixture of afferent acoustic fibers, the majority of inputs reach the primary auditive cortex of the contralateral hemisphere, especially of the dominant one [10, 35]. In right-handed people a decrease in hearing from birth or early childhood could provoke a lower auditory stimulation of the dominant hemisphere, probably encouraging a greater or complete contralateral development of language centers [35]. This could be possible also for a congenital and subclinical impairment of the right acoustic pathway and/or of the relative interposed nuclei. Thus the right hemisphere would decodify a larger number of verbal messages than the contralateral and than physiological standard levels [35]. If neuroanatomical and neurophysiological studies prove this interpretation, the use of brain stem evoked potentials could result useful in routine preoperative examinations for determining the lateralization of language. Neurosurg. Rev. 17 (1994) Mastronardi et al., Crossed aphasia 303 References [1] ALBERTML, LK OBLER: The bilingual brain. New York, Academic Press, 1978 [2] ALEXANDER MP, MR FISCHETTE, RS FISCHER: Crossed aphasias can be mirror image or anoma][ous. Case report, review and hypothesis. Brain 113 (1989) 953-973 [3] ANGELERGUESR, H HECAEN, R DJINDHAN, N JARRIE-HAZAN:Un cas d'aphasie crois6e (thrombose de l'art6re sylvienne droite chez une droiti6re). Revue Neurol 143 (1987) 294-297 [4] APRIL RS, M HAN: Crossed aphasia in a rightIhanded bilingual chinese man. Arch Neurol 37 (1980) 342-346 [5] ARDIN-DELTEIEF, A LEvI-VALENSI,G. DERRIEU: Aphasie de Broca par 16sion de l'h6misph6re droit chez une droiti6re. Rev Neurol 1 (1923) 14-21 [6] ASSAL G, E PERENTES,JP DERUAZ: Crossed aphasia in a right-handed patient. Arch Neurol 38 ,(1981) 455-458 [7] BASSO A, E CAPITANI, M LAIACONA, ME ZANOBIO: Crossed aphasia: one or more syndromes? ,Cortex 21 (1985) 25-45 [8] BERNDTSR, CC MITCHUM,TR PRICE: Short-term memory sentence comprehension. An investigation of a patient with crossed aphasia. Brain 114 (1991) 263-280 [9] BRAMWELL B: On "crossed aphasia". Lancet 1 (1899) 1473-1479 [10] BRODAL A: Neurological anatomy, in relation to clinical medicine. New York, Oxford University Press, 3rd edition, 1981 [11] BROWN JW, FR WILSON: Crossed aphasia in a dextral. A case report. Neurology 23 (1973) 907-911 [12] BRUST JCM, C PLANK, A BURKE, MMJ GOUBADIA,EB HEALTON:Language disorder in a right hander after occlusion of the right anterior cerebral artery. Neurology 32 (1982) 492-497 [13] BRYDEN MP: Laterality - Functional asymmetry in the intact brain. New York, Academic Press, 1982 [14] BURD L, G GASCON, R SWENSON, R HANKEY: Crossed aphasia in early childhood. Develop Med Child Neurol 32 (1990) 528-546 [15] CARR RS, T JACOBSON,F BOLLER: Crossed aphasia: analysis of four cases. Brain Lang 14 (1981) 190-202 [16] CHARYP: Aphasia in multilingual society: a preliminar study. In: VAID J (ed): Language processing in bilinguals: psycholinguistic mad neuropsychological perspectives. Hillsdale, New Jersey Lawrence Erlbaum Associates, 1986 [17] DAMASIOAR: Aphasia. N Engl J Med 326 (1992) 531-539 Neurosurg. Re~ 17 (1994) [18] FAGLIA L, MR ROTTOLI, LA VIGNOLO: Aphasia due to lesion confined to the right hemisphere in right handed patients: a review of the literature including the Italian cases. Ital J Neurol Sci 11 (1990) 131-144 [19] FAGLIAL, LA VIGNOLO: A case of"crossed aphasia" in which the integrity of the left hemisphere is assessed by MRI. It J Neurol Sci 11 (1990) 51-55 [20] GALLOWAY L: Towards a neuropsychological model of bilingualism and second language performance: a theoretical article with a critical review of current research and some new hypotheses. In: LONG M, S PECK, K BAILEY (eds): Research in second language acquisition. RowIey, MA, Newbury House, 1980 [21] GLONING L, K GLONING, G HAUB, R QUATEMBER: Comparison of verbal behavior in righthanded and non-right-handed patients with anatomically verified lesions of one hemisphere. Cortex 5 (1969) 4 3 - 5 2 [22] HAALANDKY, F MIRANDA:Psychometric and CT scan measurement in a case of crossed aphasia in a dextral. Brain Lang 17 (1982) 240-260 [23] HAMASAKIT, K SUZUKI, K HIRAKAWA,Y IMAHORI, S NAKAJIMA: Un cas japonais d'aphasie crois4e chez un droitier. Revue Neurol 143 (1987) 47-54 [24] HECAENH, G MAZARS, AM RAMmR, MC GOLDBLUM, L MERIENNE:Aphasie crois6e chez tin sujet droitier bilingue (vietnamien-frangais). Revue Neurol 124 (1971) 319-323 [25] HENDERSONVW: Speech fluency in crossed aphasia. Brain 106 (1983) 837-857 [26] JACKSON JH: On aphasia with left hemiplegia. Lancet (1880) 637-638 [27] JOANETTEY, M PULL, JL NESPOULOUS,A RASCOL, A ROCH LECOURS:Aphasie crois6e chez les droitiers. Revuew de la litt6rature. Revue Neurol 138 (1982) 575-586 [28] KAPUR N, B DUNKLEY: Neuropsychological analysis of a case of crossed aphasia verified at post-mortem. Brain Lang 23 (1984) 134-147 [29] KARANTHP, GM RANGAMANI:Crossed aphasia in multilinguals. Brain Lang 34 (1988) 169-180 [30] KREINDLERA, FRAD1SA, N SEVASTOPOL:La r4partition des dominances h6misph6riques. Neuropsychologia 4 (1966) 143-149 [31] MILNER B, C BRANCH, TH RASMUSSEN:Evidence for bilateral speech representation in some nonright handers. Trans Am Neurol Assoc 91 (1966) 306-308 [32] NAGARAJAD, AB TALL, G HERLEKAR, GM RANGAMANI, N SHIVASHANKAR, CR MUKUNDAN: Crossed aphasia in a dextral. Clin Neurol Neurosurg 91 (1989) 153-156141] SAKURAI~, t-] KUR- 304 ISAKI, K TAKEDA et al: Japanese crossed Wernicke's aphasia. Neurology 42 (1992) 1 4 4 - i 4 8 [33] PARADISM: The assessment of bilingual aphasia. Hillsdale, New Jersey Lawrence Erlbaum Associates, 1987 [34] PETERSEN SE, PT FOX, MI POSNER, M MINTUN, ME RAICFILE: Positron emission tomographic studies of the cortical anatomy of single-word processing. Nature 331 (1988) 585-589 [35] PUEL M, Y JOANETTE,M LEVRAT et al: Aphasie croisee chez les droitiers. Revue Neurol 138 (1982) 578-600 [36] RAICHLE M: Visual language imaging research. AANS Bulletin, Summer 1992 [37] RASMUSSENR, B MILNER: The role of early leftbrain injury in determining lateralization of cerebral functions. Ann NY Acad Sci 299 (1977) 355-369 [38] RUSSELWR, MLE ESPIR: Traumatic aphasia. Oxford, England, Oxford ,University Press, 1961 [39] RUSSEL DS, LJ RUBrNSTEIN: Pathology of Tumours of the Nervous System. Edinburgh, Edware Arnold, ed4, 1977 [40] SADASIVAMPB, V JAGANNATHAN:Crossed aphasia in a dextral. J Assoc Phys Ind 25 (1977) 167-170 [41] SAKURAIY, H KURISAKI,K TAKEDAet al: Japanese crossed Wemicke's aphasia. Neurology 42 (1992) 144-148 [42] SEGALOWITZSJ, MP BRYDEN: Individual differences in hemispheric representation of language. In: SEGALOWITZSJ (ed): Language function and brain organization. New York, Academy Press, 1983 Mastronardi et al., Crossed aphasia [43] SUSSMANNM; RC GUR, RE GUR, MJ O'CONNOR: Mutism is a consequence of callosotomy. J Neurosurg 59 (1983) 514-519 [44] TROJANOWSKI JQ, RC GREEN, DN LEVINE: Crossed aphasia in a dextral: a clinicopathological study. Neurology 30 (1980) 709-713 [45] URBAIN E, X SERON, A REMITS, A COBBEN, M VAN DER LINDEN, R MOUCI-IETTE:Aphasie croisde chez une droiti6re. A propos d'une observation. Revue Neurol 134 (1978) 751-759 [46] VAID J: Bilingualism and brain lateralization. In: SEGALOWITZ SJ (ed): Language functions and brain organization. New York, Academic Press, 1981 [47] VAID J, Brown JW, H Hecaen: Lateralization of language representation. Observations on aphasia in children left handers and anomalous dextrals. Neurology 26 (1976) 183-189 [48] YARNELLPR: Crossed dextral aphasia: a clinical radiological correlation. Brain Lang 12 (1981) 128-139 [49] ZANGWn~L OL: Two cases of crossed aphasia in dextrals. Neuropsychologia 17 (1979) 167-172 Submitted February 17, 1993. Accepted November 30, 1993. Luciano Mastronardi, M.D. Neurochirurgia Universitg "La Sapienza" Viale dell'Universitfi 30/A 1-00185 Rome Italy Neurosurg. Rev. 17 (1994)