Advertisement

Neurological Sciences

, Volume 35, Issue 5, pp 707–713 | Cite as

Positive sharp waves in the EEG of children and adults

  • A. Bruce Janati
  • Muhammad Umair
  • Naif Saad AlghasabEmail author
  • Kareemah Salem Al-Shurtan
Original Article

Abstract

Interictal epileptiform discharges (IEDs) with negative polarity have been extensively studied in the EEG literature. However, little attention has been drawn to IED with positive polarity [positive sharp waves (PSWs)]. In this paper, we discuss pathophysiological, neuroimaging, and clinical correlates of this pattern in a heterogeneous group of children and adults who demonstrated PSW in their scalp EEG. We prospectively reviewed the EEGs of 1,250 patients from a heterogeneous population over a period of 1 year. Thirty-one patients had PSW in their EEG. We documented EEG parameters as well as demographic, clinical, and neuroimaging data. Statistical analysis was performed to correlate the aforementioned data. The analysis showed that PSW is an epileptogenic pattern with localizing significance, occurring primarily in the younger age groups. Furthermore, there was a strong association of PSW with chronic and/or static CNS pathology, in particular, congenital CNS anomalies, often accompanied by psychomotor retardation. Patients with “multifocal’’ PSW invariably exhibited severe intellectual and motor deficits associated consistently with a variety of congenital CNS insults. PSW is a rare and under-reported EEG abnormality which, similar to negative IED, signifies focal epileptogenecity. The presence of PSW should prompt neuroimaging studies to investigate an associated chronic/static CNS pathology, in particular, congenital CNS anomalies. This association is particularly strong when PSW is multifocal in which case patients present with severe intellectual and motor deficits.

Keywords

Positive sharp waves (PSWs) Epilepsy EEG Epileptogenecity 

Notes

Acknowledgments

Acknowledgment for the assistance of Jeffrey F. Ricablanca, Mary Grace Lorente, Abdulmohsen S. Alghassab.

References

  1. 1.
    American Clinical Neurophysiological Society (2006) Guideline 8: guidelines for recording clinical EEG and digital media. J Clin Neurophysiol 23(2):122–124CrossRefGoogle Scholar
  2. 2.
    Blume WT (2001) Pathogenesis of Lennox–Gastaut syndrome: considerations and hypotheses. Epileptic Disord 3(4):183–196PubMedGoogle Scholar
  3. 3.
    Brazier MBA (1951) A study of the electrical fields at the surface of the head. Electroencephalogr Clin Neurophysiol: 38–52Google Scholar
  4. 4.
    Chatrian GE, Bergamini L, Dondey M et al (1974) A glossary of terms most commonly used by clinical electroencephalographers. Electroencephalogr Clin Neurophysiol 37:538–548CrossRefGoogle Scholar
  5. 5.
    Ebersole JS (1997) Defining epileptogenic foci: past, present, future. J Clin Neurophysiol 14(6):470–483PubMedCrossRefGoogle Scholar
  6. 6.
    Goldensohn ES, Purpura DP (1963) Intracellular potentials of cortical neurons during focal epileptogenic discharges. Science 139:840–842PubMedCrossRefGoogle Scholar
  7. 7.
    Kabat J, Kral P (2012) Focal cortical dysplasia. Pol J Radiol 77(2):35–43PubMedCentralPubMedCrossRefGoogle Scholar
  8. 8.
    Kellaway P, Hrachovy RA. Electroencephalography. In: Swaiman KF, Wright FS (eds) The practice of pediatric neurology, 2nd edn, pp 96–114Google Scholar
  9. 9.
    Lombroso CT (1981) Intracranial hemorrhage in the newborn. A prospective clinical and electrophysiological study of 37 cases. In: Proceedings of the IYDP commemorative International Symposium on developmental disabilities. Elsevier, Tokyo, pp 251–56Google Scholar
  10. 10.
    Lombroso CT (1985) Neonatal polygraphy in full term and premature infants: a review of normal and abnormal findings. J Clin Neurophysiol 2:105–155PubMedCrossRefGoogle Scholar
  11. 11.
    McCulloch W (1972) Mechanisms for the spread of epileptic activation of the brain. Electroencephalogr Clin Neurophysiol 32:529–544CrossRefGoogle Scholar
  12. 12.
    Maulsby RL (1971) Some guidelines for assessment of spikes and sharp waves in EEG tracings. Am J EEG Technol 11:3–16Google Scholar
  13. 13.
    Matsuo F, Knott JR (1977) Focal positive spikes in electroencephalography. Electroencephalogr Clin Neurophysiol 42:15–25PubMedCrossRefGoogle Scholar
  14. 14.
    Nowack WJ, Janati A, Antuago T (1987) Positive temporal sharp waves in the neonate. J Clin Neurophysiol 4:315–317Google Scholar
  15. 15.
    Nowack WJ, Janati A (1990) Positive sharp waves in neonatal EEG. Am J EEG Technol 30:211–221Google Scholar
  16. 16.
    Petsche H, Brazier MAB (eds) (1972) Synchronization of EEG activity in epilepsies. Springer-Verlag, New York, p 431Google Scholar
  17. 17.
    Purpura DP (1969) Stability and seizure susceptibility of immature brain. In: Jasper HH, Ward AA, Pope A (eds) Basic mechanisms of the epilepsies. Little, Brown and Co, Boston, pp 481–505Google Scholar
  18. 18.
    Seifer G, Blenkmann A, Princich JP et al. (2012) Noninvasive approach to focal cortical dystrophy. Epilepsy Res Treat. doi: 10.1155/2012/736784, Article ID 736784

Copyright information

© Springer-Verlag Italia 2013

Authors and Affiliations

  • A. Bruce Janati
    • 1
  • Muhammad Umair
    • 2
  • Naif Saad Alghasab
    • 3
    Email author
  • Kareemah Salem Al-Shurtan
    • 3
  1. 1.Center for Neurology in FairfaxFairfaxUSA
  2. 2.Dow Medical College, KKHHailKingdom of Saudi Arabia
  3. 3.Hail University, Hail, King Faisal Specialist HospitalRiyadhKingdom of Saudi Arabia

Personalised recommendations