Inter- and intraobserver variability in motor mapping of the hotspot for the abductor policis brevis muscle

BMC Neuroscience

Sandro M Krieg²  Florian Ringel²  Bernhard Meyer²  Alexander Hapfelmeier¹  Thomas Obermüller²  Theresa Hauck²  Nico Sollmann² 

[1] Institute of Medical Statistics and Epidemiology Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany;Department of Neurosurgery, Klinikum rechts der Isar, München, Germany

关键词: Hand knob;    Motor threshold;    Navigated brain stimulation;    Motor mapping;    Transcranial magnetic stimulation;    Cortical mapping;   

Others  :  1140142
DOI  :  10.1186/1471-2202-14-94

 received in 2013-05-01, accepted in 2013-09-03,  发布年份 2013

【 摘 要 】

Background

For accuracy in navigated transcranial magnetic stimulation (nTMS), determination of the hotspot location of small hand muscles is crucial because it is the basis for the resting motor threshold (RMT) and, therefore, its spatial resolution. We investigated intra- and interobserver differences of hotspot mapping to provide evidence for the reproducibility of this method.

Ten subjects underwent nTMS motor mapping of the hotspot for the abductor pollicis brevis muscle (APB) three times. The first two sessions were performed by the same examiner; the third mapping was performed by a different examiner. Distances between the first and second mappings (intraobserver variability) and between the second and third mappings (interobserver variability) were measured.

Results

Intraobserver variability had a mean of 8.1 ± 3.3 mm (limits of agreement (LOA) 1.7 to 14.6 mm), whereas mean interobserver variability was 10.3 ± 3.3 mm (LOA 3.8 to 16.7 mm). Concerning RMT, CCC was 0.725 (95% CI: 0.276; 0.914). The mean variability in the same cortical depth was measured as 5.7 ± 3.3 mm (LOA −0.7 to 12.2 mm) for intraobserver and 9.2 ± 3.3 mm (LOA 2.7 to 15.8 mm) for interobserver examinations. When evaluating the RMT, CCC was 0.709 (95% CI: 0.244; 0.909).

Conclusions

Overall, intraobserver variability showed higher reliability than interobserver variability. Our findings show that we can achieve good reliability in hotspot determination, ranging within the calculated precision of the system.

【 授权许可】

   
2013 Sollmann et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

Figure 4.

【 参考文献 】

• [1]Tarapore PE, Tate MC, Findlay AM, Honma SM, Mizuiri D, Berger MS, Nagarajan SS: Preoperative multimodal motor mapping: a comparison of magneto encephalography imaging, navigated transcranial magnetic stimulation, and direct cortical stimulation. J Neurosurg 2012, 117(2):354-362.
• [2]Picht T, Schulz J, Hanna M, Schmidt S, Suess O, Vajkoczy P: Assessment of the influence of navigated transcranial magnetic stimulation on surgical planning for tumors in or near the motor cortex. Neurosurgery 2012, 70(5):1248-1256. discussion 1256–1247
• [3]Krieg SM, Shiban E, Buchmann N, Gempt J, Foerschler A, Meyer B, Ringel F: Utility of presurgical navigated transcranial magnetic brain stimulation for the resection of tumors in eloquent motor areas. J Neurosurg 2012, 116(5):994-1001.
• [4]Picht T, Mularski S, Kuehn B, Vajkoczy P, Kombos T, Suess O: Navigated transcranial magnetic stimulation for preoperative functional diagnostics in brain tumor surgery. Neurosurg 2009, 65(6 Suppl):93-98.
• [5]Krieg SM, Shiban E, Buchmann N, Meyer B, Ringel F: Presurgical navigated transcranial magnetic brain stimulation for recurrent gliomas in motor eloquent areas. Clin Neurophysiol 2013, 124(3):522-527.
• [6]Uy J, Ridding MC, Miles TS: Stability of maps of human motor cortex made with transcranial magnetic stimulation. Brain Topogr 2002, 14(4):293-297.
• [7]Picht T, Strack V, Schulz J, Zdunczyk A, Frey D, Schmidt S, Vajkoczy P: Assessing the functional status of the motor system in brain tumor patients using transcranial magnetic stimulation. Acta Neurochir (Wien) 2012, 154(11):2075-2081.
• [8]Ilmoniemi RJ, Ruohonen J, Karhu J: Transcranial magnetic stimulation–a new tool for functional imaging of the brain. Crit Rev Biomed Eng 1999, 27(3–5):241-284.
• [9]Ruohonen J, Ilmoniemi RJ: Modeling of the stimulating field generation in TMS. Electroencephalogr Clin Neurophysiol Suppl 1999, 51:30-40.
• [10]Yousry TA, Schmid UD, Alkadhi H, Schmidt D, Peraud A, Buettner A, Winkler P: Localization of the motor hand area to a knob on the precentral gyrus. A new landmark. Brain J Neurol 1997, 120(Pt 1):141-157.
• [11]Niskanen E, Julkunen P, Saisanen L, Vanninen R, Karjalainen P, Kononen M: Group-level variations in motor representation areas of thenar and anterior tibial muscles: navigated transcranial magnetic stimulation study. Hum Brain Mapp 2010, 31(8):1272-1280.
• [12]Hattemer K, Knake S, Reis J, Rochon J, Oertel WH, Rosenow F, Hamer HM: Excitability of the motor cortex during ovulatory and anovulatory cycles: a transcranial magnetic stimulation study. Clin Endocrinol 2007, 66(3):387-393.
• [13]Carroll T, Riek S, Carson R: Reliability of the input–output properties of the cortico-spinal pathway obtained from transcranial magnetic and electrical stimulation. J Neurosci Methods 2001, 112(2):193-202.
• [14]Malcolm MP, Triggs WJ, Light KE, Shechtman O, Khandekar G, Gonzalez Rothi LJ: Reliability of motor cortex transcranial magnetic stimulation in four muscle representations. Clin Neurophysiol 2006, 117(5):1037-1046.
• [15]Miranda PC, de Carvalho M, Conceicao I, Luis ML, Ducla-Soares E: A new method for reproducible coil positioning in transcranial magnetic stimulation mapping. Electroencephalogr Clin Neurophysiol 1997, 105(2):116-123.
• [16]Mortifee PSH, Schulzer M, Eisen A: Reliability of transcranial magnetic stimulation for mapping the human motor cortex. Electroencephalogr Clin Neurophysiol 1994, 93(2):131-137.
• [17]Weiss C, Nettekoven C, Rehme AK, Neuschmelting V, Eisenbeis A, Goldbrunner R, Grefkes C: Mapping the hand, foot and face representations in the primary motor cortex - Retest reliability of neuronavigated TMS versus functional MRI. Neuroimage 2012, 66C:531-542.
• [18]Forster MT, Senft C, Hattingen E, Lorei M, Seifert V, Szelenyi A: Motor cortex evaluation by nTMS after surgery of central region tumors: a feasibility study. Acta Neurochir (Wien) 2012, 154(8):1351-1359.
• [19]Wolf SL, Butler AJ, Campana GI, Parris TA, Struys DM, Weinstein SR, Weiss P: Intra-subject reliability of parameters contributing to maps generated by transcranial magnetic stimulation in able-bodied adults. Clin Neurophysiol 2004, 115(8):1740-1747.
• [20]Conforto AB, Z’Graggen WJ, Kohl AS, Rosler KM, Kaelin-Lang A: Impact of coil position and electrophysiological monitoring on determination of motor thresholds to transcranial magnetic stimulation. Clin Neurophysiol 2004, 115(4):812-819.
• [21]Ruohonen J, Karhu J: Navigated transcranial magnetic stimulation. Neurophysiol Clin 2010, 40(1):7-17.