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Table 2: Somatosensory evoked potentials
Number/ N9‑L N9‑R N13‑L N13‑R N20‑L N20‑R N9‑ N9‑ N13‑ N13‑ N9‑ N9‑
gender/age N13/L N13/R N20/L N20/R N20/L N20/R
3/female/68 10.3 10.3 13.9 13.2 19 18.5 3.6 2.9 5.1 5.3 8.7 8.2
6/female/71 11.9 12.3 17.4 17.4 24.8 26.2 5.5 5.1 7.4 8.8 12.9 13.9
10/male/64 12.7 12.8 16.4 16.8 22.4 23 3.7 4 6 6.2 9.7 10.2
16/male/51 11.6 11.3 17.4 14.9 22.2 22.1 5.8 3.6 4.8 7.2 10.6 10.8
23/male/62 11.6 11.8 15.3 15.1 21.7 21.2 3.7 3.3 6.4 6.1 10.1 9.4
24/female/56 11.8 11.6 15.3 16.5 22 20.8 3.5 4.9 6.7 4.3 10.2 9.2
28/female/58 8.7 8.6 16.2 16.2 Abs Abs 7.5 7.6 Abs Abs Abs Abs
29/male/75 10.6 11.3 16.9 17.6 Abs 27.4 6.3 6.3 Abs 9.8 Abs 16.1
30/female/65 9.9 10.5 15.2 14.6 Abs 23.8 5.3 4.1 Abs 9.2 Abs 13.3
Mean ± SD 11 ± 1.2 11.2 ± 1.2 16 ± 1.2 15.8 ± 1.5 22 ± 1.9 22.9 ± 2.9 5 ± 1.4 4.6 ± 1.5 6.1 ± 1 7.1 ± 2 10.4 ± 1.4 11.4 ± 2.7
Range 8.7‑12.7 8.6‑12.8 13.9‑17.4 13.2‑17.6 19‑24.8 18.5‑27.4 3.5‑7.5 2.9‑7.6 4.8‑7.4 4.3‑9.8 8.7‑12.9 8.2‑16.1
Normal ≤ 11.3 ≤ 11.3 ≤ 14.9 ≤ 14.9 ≤ 22.1 ≤ 22.1 ≤ 5.0 ≤ 5.0 ≤ 6.8 ≤ 6.8 ≤ 10.9 ≤ 10.9
SD: standard deviation; L: left; R: right

Table 3: Brainstem auditory evoked potentials
Number/ I‑L I‑R III‑L III‑R V‑L V‑R Amp‑L Amp‑R I‑III/L I‑III/R III‑V/L III‑V/R I‑V/L I‑V/R
gender/age
3/female/68 1.78 1.5 3.7 3.7 5.52 5.54 2.4 2.16 1.92 2.2 1.82 1.84 3.74 4.04
6/female/71 1.7 1.64 3.74 3.86 5.84 6 2.06 1.2 2.04 2.22 2.1 2.14 4.14 4.36
23/male/62 1.68 1.7 3.96 3.86 5.86 5.72 1.98 1.76 2.28 2.16 1.9 1.86 4.18 4.02
28/female/58 1.38 1.42 3.52 3.54 5.42 5.38 1.07 1.08 2.14 2.12 1.9 1.84 4.04 3.96
29/male/75 1.74 1.48 4 4.08 6.18 6.24 2.05 0.974 2.26 2.6 2.18 2.16 4.44 4.76
30/female/65 1.76 1.76 3.92 4.02 5.86 5.94 1 1.97 2.16 2.26 1.94 1.92 4.1 4.18
Mean ± SD 1.7 ± 0.1 1.6 ± 0.1 3.8 ± 0.2 3.8 ± 0.2 5.8 ± 0.3 5.8 ± 0.3 1.8 ± 0.6 1.5 ± 0.5 2.1 ± 0.1 2.3 ± 0.2 2 ± 0.1 2 ± 0.2 4.1 ± 0.2 4.2 ± 0.3
Range 1.4‑1.8 1.4‑1.8 3.5‑4 3.5‑4.1 5.4‑6.2 5.4‑6.2 1‑2.4 1‑2.2 1.9‑2.3 2.1‑2.6 1.8‑2.2 1.8‑2.2 3.7‑4.4 4‑4.8
Normal ≤ 2.2 ≤ 2.2 ≤ 4.5 ≤ 4.5 ≤ 6.5 ≤ 6.5 ≤ 2.6 ≤ 2.6 ≤ 2.4 ≤ 2.4 ≤ 4.7 ≤ 4.7
SD: standard deviation; L: left; R: right

Table 4: Visual evoked potentials accepted that SSEP evaluates only the large diameter
Number/ P100‑P‑L P100‑P‑R P100‑G‑L P100‑G‑R fibers. [17]
gender/age
3/female/68 98.5 97.5 125 130 The current study provided evidence that the large
6/female/71 122 131 131 132 fiber dysfunction occurs in central conduction,
23/male/62 103 114 116 112
24/female/56 101 103 80.5 77.5 involving somatosensory pathway, in addition
28/female/58 105 99.5 99.5 105 to the peripheral conduction delay. [16,18] We have
29/male/75 99.5 91 90.5 104 recently reported that eHcy is an independent
30/female/65 100 104 91 108
Mean ± SD 104.1 ± 8.2 105.7 ± 13.2 104.9 ± 19.5 109.8 ± 18.3 risk factor for the development of peripheral
Range 98.5‑122 91‑131 80.5‑131 77.5‑132 neuropathy. [16] The estimated incidence of the
Normal ≤ 117 ≤ 117 ≤ 132 ≤ 132 isolated eHcy-induced neuropathy was as low as
SD: standard deviation; P: pattern reversal; G: goggles techniques; L: left, R: right
1.81% of peripheral neuropathy (our unpublished
data). The electrophysiologic features of the isolated
the visual and auditory, pathways. To the best of our eHcy-induced peripheral neuropathy are a mild,
knowledge, there is no report on central conduction in large fiber sensorimotor neuropathy with mixed
adult patients with eHcy.
neurophysiologic features of mild demyelination and
distal axonal degeneration, although the involvement
Somatosensory evoked potential evaluates the integrity of small diameter fibers cannot be dismissed. [18]
of the somatosensory pathway from peripheral to
the cortex. The pathway initiates from peripheral Elevated plasma level of homocysteine may result
segment of the large sensory fibers whose cell from deficiency of vitamin B12 and/or folate, and
bodies, the pseudomonopolar neurons, reside in the genetic predispositions such as C677T polymorphism
dorsal root ganglia. [17] The central processes of the of MTHFR. [19,20] Additionally, it may also result from
pseudomonopolar neurons enter the ipsilateral posterior various pathophysiologic conditions including
column of the spinal cord, decussate and synapse at the aging, [21,22] obesity, [23,24] diabetes mellitus, [25-27] renal
contralateral dorsal column nucleus (cuneate nucleus) function impairment, [27] medications and/or toxic
at the cervico-medullary junction where the secondary substances such as levodopa, [7,28] anti-gastric acid
order fibers start and synapse at ventro-posteriolateral agents, [29,30] anti-epileptics, [31,32] tobacco, [33] and
nucleus of thalamus, from which the third order fibers alcohol. [34-36] Because of its excitatory property which
advance to the somatosensory cortex. [17] It is commonly may promote the vulnerability of neuronal cells to

28 Neuroimmunol Neuroinflammation | Volume 2 | Issue 1 | January 15, 2015