Effectiveness and Safety of Transcranial Laser Therapy for Acute Ischemic Stroke

Abstract

MD; for the NEST-2 InvestigatorsBackground and Purpose-We hypothesized that transcranial laser therapy (TLT) can use near-infrared laser technology to treat acute ischemic stroke. The NeuroThera Effectiveness and Safety Trial-2 (NEST-2) tested the safety and efficacy of TLT in acute ischemic stroke. Methods-This double-blind, randomized study compared TLT treatment to sham control. Patients receiving tissue plasminogen activator and patients with evidence of hemorrhagic infarct were excluded. The primary efficacy end point was a favorable 90-day score of 0 to 2 assessed by the modified Rankin Scale. Other 90-day end points included the overall shift in modified Rankin Scale and assessments of change in the National Institutes of Health Stroke Scale score. Results-We randomized 660 patients: 331 received TLT and 327 received sham; 120 (36.3%) in the TLT group achieved favorable outcome versus 101 (30.9%), in the sham group (Pϭ0.094), odds ratio 1.38 (95% CI, 0.95 to 2.00).Comparable results were seen for the other outcome measures. Although no prespecified test achieved significance, a post hoc analysis of patients with a baseline National Institutes of Health Stroke Scale score of Ͻ16 showed a favorable outcome at 90 days on the primary end point (PϽ0.044). Mortality rates and serious adverse events did not differ between groups with 17.5% and 17.4% mortality, 37.8% and 41.8% serious adverse events for TLT and sham, respectively. Conclusions-TLT within 24 hours from stroke onset demonstrated safety but did not meet formal statistical significance for efficacy. However, all predefined analyses showed a favorable trend, consistent with the previous clinical trial (NEST-1). Both studies indicate that mortality and adverse event rates were not adversely affected by TLT. A definitive trial with refined baseline National Institutes of Health Stroke Scale exclusion criteria is planned.

Photobiomodulation inside the brain: a novel method of applying near-infrared light intracranially and its impact on dopaminergic cell survival in MPTP-treated mice

“…In rabbits, it has been estimated that NIr from a laser device may reach a depth of 25-30 mm from the cortical surface, 21 while a similar estimate of approximately 20 mm has been predicted in humans. 47 However, there would be considerable attenuation and loss of power intensity from the cranial surface and through the brain parenchyma. Shaw and colleagues 38 have suggested that in mice, there is an approximately 90% decline in the NIr signal inside the cranium after external application via a light-emitting diode (LED).…”

Transcranial low-level laser therapy may improve alertness and awareness in traumatic brain injured subjects with severe disorders of consciousness: a case series

“…[8,14] Positive sham-controlled studies in acute stroke patients included the single T-LLT stimulation of 20 points according to the 10-20 system for one minute each, the wave length was 808 nm and the intensity 10 mW/cm 2 . [15,16,17] In embolized rabbit's brain, Lapchak and De Taboada successfully showed that T-LLT (wave length 808 nm, intensity 10 mW/cm 2 ) significantly increased the cortical ATP, the penetration depth was 20 -30 mm. [18] Accordingly the authors of the acute stroke studies speculated that the transcranial laser could have activated the respiratory chain, namely the complex IV, thus increasing the ATP production and helping cell recuperation.…”

“…[8] The exclusive frontal application followed the previous clinical reports on the beneficial effects of N-LLT. [15,20] Further N-LLT was assumed to improve the cell metabolism of the stimulated brain areas. In the tDCS trials, the authors stimulated the left dorsolateral prefrontal cortex (DLPF) which is said to receive visual and and somatosensory input from the parietal heteromodal association cortices regarding vision, motion, spatial orientation and tactile sensations, and projects to subcortical monoaminergic and cholinergic sources.…”

Transcranial Low-level Laser Therapy may Improve Alertness and Awareness in Traumatic Brain Injured Subjects with Severe Disorders of Consciousness: A Case Series

“…The exclusive frontal application followed the previous clinical reports on the beneficial effects of N-LLT [15,20]. Further N-LLT was assumed to improve the cell metabolism of the stimulated brain areas.…”

“…With the transfrontal application one should keep in mind the variable size of the frontal sinus, the bone around the sinus is thicker, and not seldom a sinusitis affects severely affected chronic patients. A thick bone and fluid, however, decrease the Positive sham-controlled studies in acute stroke patients included the single T-LLT stimulation of 20 points according to the 10-20 system for one minute each, the wave length was 808 nm and the intensity 10 mW/cm 2 [15][16][17]. In embolized rabbit's brain, Lapchak and De Taboada successfully showed that T-LLT (wave length 808 nm, intensity 10 mW/cm 2 ) significantly increased the cortical ATP, the penetration depth was 20-30 mm [18].…”