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The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy
Epilepsy Research (2009) 87, 144—147
journal homepage: www.elsevier.com/locate/epilepsyres
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Judith M. Hoffmann, Christian E. Elger, Ailing A. Kleefuss-Lie ∗ Department of Epileptology, University of Bonn, Sigmund-Freud Str. 25, 53105 Bonn, Germany Received 6 June 2009; received in revised form 5 August 2009; accepted 9 August 2009 Available online 11 September 2009
KEYWORDS Coughing; Hypersalivation; Ictal semiology; Temporal lobe epilepsy; Mesial; Extra-mesial
Summary Analysis of ictal semiology is essential to presurgical evaluation of epilepsy patients providing information on seizure origin. To assess the significance of hypersalivation and postictal coughing for seizure origin in temporal lobe epilepsy (TLE), we analyzed video/EEG monitoring documented seizures of 107 adult patients for these seizure elements with respect to frequency and sequence of occurrence in relation to epileptogenic origin, comparing mesial versus extra-mesial and left versus right. Hypersalivation was rare, but occurred exclusively in seizures of mesial origin (9.4%). Comparison between left (11.4%) and right (6.9%) mesial origin was statistically insignificant. Postictal coughing also occurred exclusively in seizures of mesial onset (6.3%). Again, comparison between left (5.7%) and right (6.9%) mesial seizure onset was statistically insignificant. Thus, hypersalivation and postictal coughing are rare seizure phenomena in TLE, but their occurrence strongly support mesial seizure origin. © 2009 Elsevier B.V. All rights reserved.
Introduction With the expanding significance of non-invasive presurgical evaluation in TLE patients, the analysis of ictal semiology becomes increasingly important for the selection of these candidates. A wide range of autonomic phenomena have been described to occur in TLE, some of these being assigned valuable information on seizure origin. Hypersalivation has so far been reported in seizures of temporal origin (Shah et al., 2006; Janszky et al., 2007). However, a clear differentiation between mesial and extra-mesial seizure onset has not
∗ Corresponding author. Tel.: +49 228 287 19342; fax: +49 228 287 14486. E-mail address: [email protected] (A.A. Kleefuss-Lie).
been presented to date. Several studies have analyzed postictal coughing in TLE with contradictory results concerning its localizing significance (Van Ness et al., 1993; Bogolioubov et al., 1994; Foldvary et al., 1997; Gil-Nagel and Risinger, 1997; Fauser et al., 2004; Tezer et al., 2004; Janszky et al., 2007). Thus, the clinical value of hypersalivation and postictal coughing in TLE with regard to localization of the seizure focus needs further assessment. We have studied video/EEG monitoring documented seizures of adult TLE patients with mesial or extra-mesial seizure onset for an extensive set of defined seizure elements in order to analyze their localizing and/or lateralizing value in TLE. For our present study, we have focused on the two autonomic phenomena hypersalivation and postictal coughing. We aimed to determine whether hypersalivation and postictal coughing represent signs of lateralization of seizure origin, and/or signs of localiza-
0920-1211/$ — see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.eplepsyres.2009.08.005
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Table 1
145
Clinical data of patients. Mesial seizure origin
Extra-mesial seizure origin
Number of patients
Left mesial: n = 35 Right mesial: n = 29 Total: n = 64
Left extra-mesial: n = 24 Right extra-mesial: n = 19 Total: n = 43
Sex Mean age ± SEM Mean seizure duration ± SEM
30 F, 34 M 39 ± 10 years 86 ± 40 s
27 F, 16 M 36 ± 10 years 60 ± 31 s
tion differentiating between mesial and extra-mesial seizure onset.
Methods Patients The study was performed in accordance with the Declaration of Helsinki and approved by the local ethics committee. We have analyzed 107 surgically treated adult patients with medically refractory TLE of mesial or extra-mesial seizure origin (for clinical data of patients see Table 1; for histological data see Table 2). All patients had complete presurgical evaluation, including medical, neurological and neuropsychological examination, video/EEG monitoring, and cranial MRI, and were postoperatively seizure-free for at least 2 years after epilepsy surgery. From each of these 107 TLE patients, the first presurgical video/EEG monitoring documented seizure was analyzed for a set of defined clinical seizure elements in relation to mesial versus extra-mesial and left versus right seizure origin. In each analyzed seizure, every single seizure phenomenon was listed according to the chronological order of its occurrence after seizure onset. To this end, only objective seizure elements were analyzed; auras were not included in this semiological study. The analysis was performed by two independent investigators with profound clinical epileptological experience, who were blinded to clinical details and to the results of the monitoring.
Table 2
Histological data of patients.
Seizure origin
Histology
Number of patients
Mesial
Ammon’s horn sclerosis
Left: n = 35 (a) Right: n = 29 (a) Total: n = 64 (a)
Extra-mesial
Hamartoma
Left: n = 4 (b) Right: n = 5 (b) Total: n = 9 (b)
Extra-mesial
Astrocytoma
Left: n = 11 (c) Right: n = 4 (b) Total: n = 15 (b and c)
Extra-mesial
Ganglioglioma
Left: n = 9 (b) Right: n = 10 (b) Total: n = 19 (b)
Surgical procedures performed: (a) selective amygdalohippocampectomy; (b) lesionectomy; (c) two cases of left-sided extra-mesial astrocytoma were treated by lateral temporal lobe resection, all other cases of astrocytomas were treated by lesionectomy.
Data analysis Every single seizure element was numbered consecutively and analyzed using Excel for the investigation of frequency and chronological sequence of occurrence. Statistical analysis was performed using SPSS 9.0. Group effects were determined by One-way Analysis of Variance (ANOVA). Group comparison was carried out using Wilcoxon’s rank-sum test. The level of significance was set at p < 0.05.
Results Frequency of hypersalivation Hypersalivation was observed in 6/64 (9.4%) seizures of mesial origin and in 0/43 (0%) seizures of extra-mesial origin (p = 0.028; Table 3). Taking into account the side of seizure onset, hypersalivation was found in 4/35 (11.4%) of the left mesially and 2/29 (6.9%) of the right mesially originating seizures (Table 3). There was no significant difference in occurrence of hypersalivation between the left and right mesial group (p = 0.698). Noteworthy, hypersalivation was never observed in seizures with extra-mesial onset. Thus, hypersalivation was rare, but occurred exclusively in seizures of mesial origin.
Frequency of postictal coughing Postictal coughing was observed in 4/64 (6.3%) seizures of mesial origin and in 0/43 (0%) seizures of extra-mesial origin (p = 0.035; Table 4). Taking into account the side of seizure onset, postictal coughing was found in 2/35 (5.7%) of the left mesially and 2/29 (6.9%) of the right mesially originating seizures (Table 4). There was no significant difference in occurrence of postictal coughing between the left and right mesial group (p = 0.807). Notably, postictal coughing was never observed in extra-mesially originating seizures. Thus, postictal coughing occurred rarely, but exclusively in seizures with mesial onset. Table 3 Number of patients with hypersalivation in mesial and extra-mesial TLE. Mesial
Extra-mesial
Left Right
4/35 (11.4%) 2/29 (6.9%)
0/24 (0%) 0/19 (0%)
Total
6/64 (9.4%)
0/43 (0%)
146
J.M. Hoffmann et al.
Table 4 Number of patients with postictal coughing in mesial and extra-mesial TLE. Mesial
Extra-mesial
Left Right
2/35 (5.7%) 2/29 (6.9%)
0/24 (0%) 0/19 (0%)
Total
4/64 (6.3%)
0/43 (0%)
Discussion The detailed and precise analysis of seizure semiology is essential for the evaluation of patients for epilepsy surgery, providing information about the site of seizure onset (Marks and Laxer, 1998). For TLE, the differentiation between mesial and extra-mesial etiology is important for therapeutical and prognostic factors. The differentiation results in different options for surgical approaches, especially with regard to sparing of the hippocampus. In addition, differences in etiology and surgical procedure influence postoperative outcome including seizure control, cognitive and memory performance, neurological deficits, and psychiatric symptoms. For TLE, several semiological phenomena have been described as typical, including aura, behavioral arrest, and oro-alimentary automatisms (Kotagal et al., 1995; Gil-Nagel and Risinger, 1997; Saint-Hilaire and Lee, 2000). Additionally, a large set of autonomic symptoms has been reported to occur in TLE, some of these being assigned valuable information on seizure origin. Among these, hypersalivation and postictal coughing have been described as rare features of TLE (Gil-Nagel and Risinger, 1997; Shah et al., 2006). However, the lateralizing and/or localizing value of many semiological elements have not yet been finally determined. Thus, the definition of a valid set of semiological features with clear informative value on the site of seizure onset would be fundamental for the identification of patients suitable for non-invasive presurgical evaluation. In our present study, we have analyzed a battery of semiological elements in adult TLE patients with regard to their frequency and their sequence of occurrence in relation to the epileptogenic (mesial versus extra-mesial; left versus right) origin. We have focused our analyses on two autonomic symptoms: hypersalivation and postictal coughing. Only few data exist on hypersalivation in TLE. So far, hypersalivation has been reported as a rare semiological element of temporally originating seizures without statistical significance regarding lateralization (Shah et al., 2006; Janszky et al., 2007). However, these studies do not present clear differentiation between mesial and extramesial seizure onset. In our study, we show evidence that in TLE, hypersalivation occurs exclusively in seizures with mesial seizure onset. Comparison between left and right mesial origin was statistically insignificant. Thus, the occurrence of hypersalivation in TLE strongly supports mesial seizure onset, but does not further differentiate lateralization. Several studies have investigated postictal coughing in TLE with contradictory results concerning its localizing significance. Gil-Nagel and Risinger (1997) found that postictal coughing occurred with similar frequency in hippocampal
and extrahippocampal seizures. In contrast, Foldvary et al. (1997) reported that postictal coughing presented only in temporal seizures of mesial origin, and never in temporal seizures of extra-mesial origin. Moreover, Van Ness et al. (1993) and Bogolioubov et al. (1994) observed a trend towards right sided lateralization and mesial localization for postictal coughing. Tezer et al. (2004) found that postictal coughing was significantly higher in right TLE, as compared to left TLE; however, the study focussed on lateralization and did not analyze mesial versus extra-mesial seizure onset. In contrast, Janszky et al. (2007) observed that postictal coughing did not have a significant lateralizing value in TLE; again, the study focussed on lateralization and did not analyze mesial versus extra-mesial seizure origin. Finally, Fauser et al. (2004) reported a trend towards left-sided lateralization and a tendency towards mesial localization for postictal coughing. Taking these findings into account, all studies except Gil-Nagel and Risinger (1997) show at least a clear preponderance, if not even a significance of mesial seizure onset. Our group aimed to reach a statistical significance in this issue and to clarify the informative value of postictal coughing on seizure origin in TLE. We clearly found that postictal coughing is a rare semiological element, presenting exclusively in seizures of mesial origin. Interestingly, it has been hypothesized that autonomic features, including phenomena such as hypersalivation and postictal coughing, might be more associated with the nondominant than the dominant temporal lobe (see also Shah et al., 2006). With regard to this issue, we have compared the side of epileptogenic focus with the side of language dominance in those patients, who showed hypersalivation or postictal coughing (Table 5). For hypersalivation, the epileptogenic focus is located in the dominant temporal lobe in four patients, and in the non-dominant temporal lobe in two patients. For postictal coughing, the epileptogenic focus is located in the dominant temporal lobe in two patients, and in the non-dominant temporal lobe in the other two patients. So far, our present data do not support the hypothesis that hypersalivation and postictal coughing might be more associated with the non-dominant temporal lobe. However, the present sample is small, so that further studies with larger numbers of patients are needed to clarify this point.
Table 5 Comparison of side of epileptogenic focus with side of language dominance in patients with hypersalivation (H1—H6) and postictal coughing (PC1—PC4). Patient
Side of epileptogenic focus
Side of language dominance
H1 H2 H3 H4 H5 H6 PC1 PC2 PC3 PC4
Left Left Left Left Right Right Left Left Right Right
Left Left Left Left Left Left Left Left Left Left
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Although the precise analysis of seizure semiology is unquestionably important, it should never be exclusively relied on for the identification of the site of seizure onset. Each semiological element may incorrectly localize seizure origin. Actually, it can sometimes point out the site of propagation rather than origination (for review see So, 2006). In addition, the age of the patients has always to be considered, as semiological elements in adults may be missing in seizures of adolescents and children (Olbrich et al., 2002; So, 2006). Thus, seizure semiology should always be integrated with EEG, neuroimaging, and neuropsychological data to determine the site of seizure onset. Nevertheless, the compilation of a reliable and valid set of semiological features with lateralizing and/or localizing value is of great significance for seizure classification as well as for optimal patient selection with regard to epilepsy surgery.
References Bogolioubov, A., Walczak, T., Bazil, C., 1994. Postictal cough and temporal lobe epilepsy. Epilepsia 35 (Suppl. 8), 16. Fauser, S., Wuwer, Y., Gierschner, C., Schulze-Bonhage, A., 2004. The localizing and lateralizing value of ictal/postictal coughing in patients with focal epilepsies. Seizure 13, 403—410. Foldvary, N., Lee, N., Thwaites, G., Mascha, E., Hammel, J., Kim, H., Friedman, A.H., Radtke, R.A., 1997. Clinical and electrographic manifestations of lesional neocortical temporal lobe epilepsy. Neurology 49, 757—763.
147
Gil-Nagel, A., Risinger, M.W., 1997. Ictal semiology in hippocampal versus extrahippocampal temporal lobe epilepsy. Brain 120, 183—192. Janszky, J., Fogarasi, A., Toth, V., Magalova, V., Gyimesi, C., Kovacs, N., Schulz, R., Ebner, A., 2007. Peri-ictal vegetative symptoms in temporal lobe epilepsy. Epilepsy Behav. 11, 125—129. Kotagal, P., Lüders, H.O., Williams, G., Nichols, T.R., McPherson, J., 1995. Psychomotor seizures of temporal lobe onset: analysis of symptom clusters and sequences. Epilepsy Res. 20, 49—67. Marks Jr., W.J., Laxer, K.D., 1998. Semiology of temporal lobe seizures: value in lateralizing the seizure focus. Epilepsia 39, 721—726. Olbrich, A., Urak, L., Gröppel, G., Serles, W., Novak, K., Porsche, B., Benninger, F., Czech, T., Baumgartner, C., Feucht, M., 2002. Semiology of temporal lobe epilepsy in children and adolescents. Value in lateralizing the seizure onset zone. Epilepsy Res. 48, 103—110. Saint-Hilaire, J.M., Lee, M.A., 2000. Localizing and lateralizing value of epileptic symptoms in temporal lobe epilepsy. Can. J. Neurol. Sci. 27 (Suppl. 1), pp. 1—5 and 20—21. Shah, J., Zhai, H., Fuerst, D., Watson, C., 2006. Hypersalivation in temporal lobe epilepsy. Epilepsia 47, 644—651. So, E.L., 2006. Value and limitations of seizure semiology in localizing seizure onset. J. Clin. Neurophysiol. 23, 353—357. Tezer, F.I., Kurne, A., Soylu, A.R., Saygi, S., 2004. Effects of lateralisation and gender on temporal lobe ictal behaviour associated with hippocampal sclerosis. Seizure 13, 418—424. Van Ness, P.C., Marotta, J., Kucera, A., Klem, G., Chee, M., 1993. Postictal cough is a sign of temporal lobe epilepsy. Neurology 43, A273—A274.
journal homepage: www.elsevier.com/locate/epilepsyres
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Judith M. Hoffmann, Christian E. Elger, Ailing A. Kleefuss-Lie ∗ Department of Epileptology, University of Bonn, Sigmund-Freud Str. 25, 53105 Bonn, Germany Received 6 June 2009; received in revised form 5 August 2009; accepted 9 August 2009 Available online 11 September 2009
KEYWORDS Coughing; Hypersalivation; Ictal semiology; Temporal lobe epilepsy; Mesial; Extra-mesial
Summary Analysis of ictal semiology is essential to presurgical evaluation of epilepsy patients providing information on seizure origin. To assess the significance of hypersalivation and postictal coughing for seizure origin in temporal lobe epilepsy (TLE), we analyzed video/EEG monitoring documented seizures of 107 adult patients for these seizure elements with respect to frequency and sequence of occurrence in relation to epileptogenic origin, comparing mesial versus extra-mesial and left versus right. Hypersalivation was rare, but occurred exclusively in seizures of mesial origin (9.4%). Comparison between left (11.4%) and right (6.9%) mesial origin was statistically insignificant. Postictal coughing also occurred exclusively in seizures of mesial onset (6.3%). Again, comparison between left (5.7%) and right (6.9%) mesial seizure onset was statistically insignificant. Thus, hypersalivation and postictal coughing are rare seizure phenomena in TLE, but their occurrence strongly support mesial seizure origin. © 2009 Elsevier B.V. All rights reserved.
Introduction With the expanding significance of non-invasive presurgical evaluation in TLE patients, the analysis of ictal semiology becomes increasingly important for the selection of these candidates. A wide range of autonomic phenomena have been described to occur in TLE, some of these being assigned valuable information on seizure origin. Hypersalivation has so far been reported in seizures of temporal origin (Shah et al., 2006; Janszky et al., 2007). However, a clear differentiation between mesial and extra-mesial seizure onset has not
∗ Corresponding author. Tel.: +49 228 287 19342; fax: +49 228 287 14486. E-mail address: [email protected] (A.A. Kleefuss-Lie).
been presented to date. Several studies have analyzed postictal coughing in TLE with contradictory results concerning its localizing significance (Van Ness et al., 1993; Bogolioubov et al., 1994; Foldvary et al., 1997; Gil-Nagel and Risinger, 1997; Fauser et al., 2004; Tezer et al., 2004; Janszky et al., 2007). Thus, the clinical value of hypersalivation and postictal coughing in TLE with regard to localization of the seizure focus needs further assessment. We have studied video/EEG monitoring documented seizures of adult TLE patients with mesial or extra-mesial seizure onset for an extensive set of defined seizure elements in order to analyze their localizing and/or lateralizing value in TLE. For our present study, we have focused on the two autonomic phenomena hypersalivation and postictal coughing. We aimed to determine whether hypersalivation and postictal coughing represent signs of lateralization of seizure origin, and/or signs of localiza-
0920-1211/$ — see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.eplepsyres.2009.08.005
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Table 1
145
Clinical data of patients. Mesial seizure origin
Extra-mesial seizure origin
Number of patients
Left mesial: n = 35 Right mesial: n = 29 Total: n = 64
Left extra-mesial: n = 24 Right extra-mesial: n = 19 Total: n = 43
Sex Mean age ± SEM Mean seizure duration ± SEM
30 F, 34 M 39 ± 10 years 86 ± 40 s
27 F, 16 M 36 ± 10 years 60 ± 31 s
tion differentiating between mesial and extra-mesial seizure onset.
Methods Patients The study was performed in accordance with the Declaration of Helsinki and approved by the local ethics committee. We have analyzed 107 surgically treated adult patients with medically refractory TLE of mesial or extra-mesial seizure origin (for clinical data of patients see Table 1; for histological data see Table 2). All patients had complete presurgical evaluation, including medical, neurological and neuropsychological examination, video/EEG monitoring, and cranial MRI, and were postoperatively seizure-free for at least 2 years after epilepsy surgery. From each of these 107 TLE patients, the first presurgical video/EEG monitoring documented seizure was analyzed for a set of defined clinical seizure elements in relation to mesial versus extra-mesial and left versus right seizure origin. In each analyzed seizure, every single seizure phenomenon was listed according to the chronological order of its occurrence after seizure onset. To this end, only objective seizure elements were analyzed; auras were not included in this semiological study. The analysis was performed by two independent investigators with profound clinical epileptological experience, who were blinded to clinical details and to the results of the monitoring.
Table 2
Histological data of patients.
Seizure origin
Histology
Number of patients
Mesial
Ammon’s horn sclerosis
Left: n = 35 (a) Right: n = 29 (a) Total: n = 64 (a)
Extra-mesial
Hamartoma
Left: n = 4 (b) Right: n = 5 (b) Total: n = 9 (b)
Extra-mesial
Astrocytoma
Left: n = 11 (c) Right: n = 4 (b) Total: n = 15 (b and c)
Extra-mesial
Ganglioglioma
Left: n = 9 (b) Right: n = 10 (b) Total: n = 19 (b)
Surgical procedures performed: (a) selective amygdalohippocampectomy; (b) lesionectomy; (c) two cases of left-sided extra-mesial astrocytoma were treated by lateral temporal lobe resection, all other cases of astrocytomas were treated by lesionectomy.
Data analysis Every single seizure element was numbered consecutively and analyzed using Excel for the investigation of frequency and chronological sequence of occurrence. Statistical analysis was performed using SPSS 9.0. Group effects were determined by One-way Analysis of Variance (ANOVA). Group comparison was carried out using Wilcoxon’s rank-sum test. The level of significance was set at p < 0.05.
Results Frequency of hypersalivation Hypersalivation was observed in 6/64 (9.4%) seizures of mesial origin and in 0/43 (0%) seizures of extra-mesial origin (p = 0.028; Table 3). Taking into account the side of seizure onset, hypersalivation was found in 4/35 (11.4%) of the left mesially and 2/29 (6.9%) of the right mesially originating seizures (Table 3). There was no significant difference in occurrence of hypersalivation between the left and right mesial group (p = 0.698). Noteworthy, hypersalivation was never observed in seizures with extra-mesial onset. Thus, hypersalivation was rare, but occurred exclusively in seizures of mesial origin.
Frequency of postictal coughing Postictal coughing was observed in 4/64 (6.3%) seizures of mesial origin and in 0/43 (0%) seizures of extra-mesial origin (p = 0.035; Table 4). Taking into account the side of seizure onset, postictal coughing was found in 2/35 (5.7%) of the left mesially and 2/29 (6.9%) of the right mesially originating seizures (Table 4). There was no significant difference in occurrence of postictal coughing between the left and right mesial group (p = 0.807). Notably, postictal coughing was never observed in extra-mesially originating seizures. Thus, postictal coughing occurred rarely, but exclusively in seizures with mesial onset. Table 3 Number of patients with hypersalivation in mesial and extra-mesial TLE. Mesial
Extra-mesial
Left Right
4/35 (11.4%) 2/29 (6.9%)
0/24 (0%) 0/19 (0%)
Total
6/64 (9.4%)
0/43 (0%)
146
J.M. Hoffmann et al.
Table 4 Number of patients with postictal coughing in mesial and extra-mesial TLE. Mesial
Extra-mesial
Left Right
2/35 (5.7%) 2/29 (6.9%)
0/24 (0%) 0/19 (0%)
Total
4/64 (6.3%)
0/43 (0%)
Discussion The detailed and precise analysis of seizure semiology is essential for the evaluation of patients for epilepsy surgery, providing information about the site of seizure onset (Marks and Laxer, 1998). For TLE, the differentiation between mesial and extra-mesial etiology is important for therapeutical and prognostic factors. The differentiation results in different options for surgical approaches, especially with regard to sparing of the hippocampus. In addition, differences in etiology and surgical procedure influence postoperative outcome including seizure control, cognitive and memory performance, neurological deficits, and psychiatric symptoms. For TLE, several semiological phenomena have been described as typical, including aura, behavioral arrest, and oro-alimentary automatisms (Kotagal et al., 1995; Gil-Nagel and Risinger, 1997; Saint-Hilaire and Lee, 2000). Additionally, a large set of autonomic symptoms has been reported to occur in TLE, some of these being assigned valuable information on seizure origin. Among these, hypersalivation and postictal coughing have been described as rare features of TLE (Gil-Nagel and Risinger, 1997; Shah et al., 2006). However, the lateralizing and/or localizing value of many semiological elements have not yet been finally determined. Thus, the definition of a valid set of semiological features with clear informative value on the site of seizure onset would be fundamental for the identification of patients suitable for non-invasive presurgical evaluation. In our present study, we have analyzed a battery of semiological elements in adult TLE patients with regard to their frequency and their sequence of occurrence in relation to the epileptogenic (mesial versus extra-mesial; left versus right) origin. We have focused our analyses on two autonomic symptoms: hypersalivation and postictal coughing. Only few data exist on hypersalivation in TLE. So far, hypersalivation has been reported as a rare semiological element of temporally originating seizures without statistical significance regarding lateralization (Shah et al., 2006; Janszky et al., 2007). However, these studies do not present clear differentiation between mesial and extramesial seizure onset. In our study, we show evidence that in TLE, hypersalivation occurs exclusively in seizures with mesial seizure onset. Comparison between left and right mesial origin was statistically insignificant. Thus, the occurrence of hypersalivation in TLE strongly supports mesial seizure onset, but does not further differentiate lateralization. Several studies have investigated postictal coughing in TLE with contradictory results concerning its localizing significance. Gil-Nagel and Risinger (1997) found that postictal coughing occurred with similar frequency in hippocampal
and extrahippocampal seizures. In contrast, Foldvary et al. (1997) reported that postictal coughing presented only in temporal seizures of mesial origin, and never in temporal seizures of extra-mesial origin. Moreover, Van Ness et al. (1993) and Bogolioubov et al. (1994) observed a trend towards right sided lateralization and mesial localization for postictal coughing. Tezer et al. (2004) found that postictal coughing was significantly higher in right TLE, as compared to left TLE; however, the study focussed on lateralization and did not analyze mesial versus extra-mesial seizure onset. In contrast, Janszky et al. (2007) observed that postictal coughing did not have a significant lateralizing value in TLE; again, the study focussed on lateralization and did not analyze mesial versus extra-mesial seizure origin. Finally, Fauser et al. (2004) reported a trend towards left-sided lateralization and a tendency towards mesial localization for postictal coughing. Taking these findings into account, all studies except Gil-Nagel and Risinger (1997) show at least a clear preponderance, if not even a significance of mesial seizure onset. Our group aimed to reach a statistical significance in this issue and to clarify the informative value of postictal coughing on seizure origin in TLE. We clearly found that postictal coughing is a rare semiological element, presenting exclusively in seizures of mesial origin. Interestingly, it has been hypothesized that autonomic features, including phenomena such as hypersalivation and postictal coughing, might be more associated with the nondominant than the dominant temporal lobe (see also Shah et al., 2006). With regard to this issue, we have compared the side of epileptogenic focus with the side of language dominance in those patients, who showed hypersalivation or postictal coughing (Table 5). For hypersalivation, the epileptogenic focus is located in the dominant temporal lobe in four patients, and in the non-dominant temporal lobe in two patients. For postictal coughing, the epileptogenic focus is located in the dominant temporal lobe in two patients, and in the non-dominant temporal lobe in the other two patients. So far, our present data do not support the hypothesis that hypersalivation and postictal coughing might be more associated with the non-dominant temporal lobe. However, the present sample is small, so that further studies with larger numbers of patients are needed to clarify this point.
Table 5 Comparison of side of epileptogenic focus with side of language dominance in patients with hypersalivation (H1—H6) and postictal coughing (PC1—PC4). Patient
Side of epileptogenic focus
Side of language dominance
H1 H2 H3 H4 H5 H6 PC1 PC2 PC3 PC4
Left Left Left Left Right Right Left Left Right Right
Left Left Left Left Left Left Left Left Left Left
The localizing value of hypersalivation and postictal coughing in temporal lobe epilepsy Although the precise analysis of seizure semiology is unquestionably important, it should never be exclusively relied on for the identification of the site of seizure onset. Each semiological element may incorrectly localize seizure origin. Actually, it can sometimes point out the site of propagation rather than origination (for review see So, 2006). In addition, the age of the patients has always to be considered, as semiological elements in adults may be missing in seizures of adolescents and children (Olbrich et al., 2002; So, 2006). Thus, seizure semiology should always be integrated with EEG, neuroimaging, and neuropsychological data to determine the site of seizure onset. Nevertheless, the compilation of a reliable and valid set of semiological features with lateralizing and/or localizing value is of great significance for seizure classification as well as for optimal patient selection with regard to epilepsy surgery.
References Bogolioubov, A., Walczak, T., Bazil, C., 1994. Postictal cough and temporal lobe epilepsy. Epilepsia 35 (Suppl. 8), 16. Fauser, S., Wuwer, Y., Gierschner, C., Schulze-Bonhage, A., 2004. The localizing and lateralizing value of ictal/postictal coughing in patients with focal epilepsies. Seizure 13, 403—410. Foldvary, N., Lee, N., Thwaites, G., Mascha, E., Hammel, J., Kim, H., Friedman, A.H., Radtke, R.A., 1997. Clinical and electrographic manifestations of lesional neocortical temporal lobe epilepsy. Neurology 49, 757—763.
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Gil-Nagel, A., Risinger, M.W., 1997. Ictal semiology in hippocampal versus extrahippocampal temporal lobe epilepsy. Brain 120, 183—192. Janszky, J., Fogarasi, A., Toth, V., Magalova, V., Gyimesi, C., Kovacs, N., Schulz, R., Ebner, A., 2007. Peri-ictal vegetative symptoms in temporal lobe epilepsy. Epilepsy Behav. 11, 125—129. Kotagal, P., Lüders, H.O., Williams, G., Nichols, T.R., McPherson, J., 1995. Psychomotor seizures of temporal lobe onset: analysis of symptom clusters and sequences. Epilepsy Res. 20, 49—67. Marks Jr., W.J., Laxer, K.D., 1998. Semiology of temporal lobe seizures: value in lateralizing the seizure focus. Epilepsia 39, 721—726. Olbrich, A., Urak, L., Gröppel, G., Serles, W., Novak, K., Porsche, B., Benninger, F., Czech, T., Baumgartner, C., Feucht, M., 2002. Semiology of temporal lobe epilepsy in children and adolescents. Value in lateralizing the seizure onset zone. Epilepsy Res. 48, 103—110. Saint-Hilaire, J.M., Lee, M.A., 2000. Localizing and lateralizing value of epileptic symptoms in temporal lobe epilepsy. Can. J. Neurol. Sci. 27 (Suppl. 1), pp. 1—5 and 20—21. Shah, J., Zhai, H., Fuerst, D., Watson, C., 2006. Hypersalivation in temporal lobe epilepsy. Epilepsia 47, 644—651. So, E.L., 2006. Value and limitations of seizure semiology in localizing seizure onset. J. Clin. Neurophysiol. 23, 353—357. Tezer, F.I., Kurne, A., Soylu, A.R., Saygi, S., 2004. Effects of lateralisation and gender on temporal lobe ictal behaviour associated with hippocampal sclerosis. Seizure 13, 418—424. Van Ness, P.C., Marotta, J., Kucera, A., Klem, G., Chee, M., 1993. Postictal cough is a sign of temporal lobe epilepsy. Neurology 43, A273—A274.