Stroke is the second to third most common cause of death in Adults,and more than a third of people who survive a storke will have Severe disability. Therapeutic options currently centre on fibrinolytic Treatment , but its limitations restrict use to a small proportion of Patients.Althougu a wide range of neuroprotective substances has Been effective in experimental models,they have repeatedly failed in Clinical trials because of toxicity or loss of effectiveness . Recent Strategies based on neuroplasticity and cellular therapy have shown Significant efficacy in improving functional recovery in experimental Models , although further study is still necessary to clarify how the brain responds to ischemic damage and is able to reorganize itself in the long term.As steps should still be taken to ensure the safety and feasibility of treatments based on neuroplasticity and cellular therapy.LLLT might be alternatively potential.

The Neuro Thera Effectiveness and Safety Trial-1（NEST-1） Study evaluated the safety and preliminary effectiveness of the Neuro Thera Laser System（NLS）in the ability to improve 90-day Outcomes in ischemic stroke patients treated within 24 hours from Stroke onset. The NLS therapeutic approach involves use of 808nm Infrared laser irradiating the shaved head of the patient an about 1 J/cm2 . This was a prospective , intention-to-treat , multicenter, International , double-blind , trial involving 120 ischemic stroke Patients treated,randomized 2:1 ratio , with 79 patients in the active Treatment group and 41 in the sham （placebo）control group.Only Patients with baseline stroke severity measured by National Institutes Of Health Stroke Scale（NIHSS）scores of 7 to 22 were included. Patients who received tissue plasminogen activator were excluded. Outcome measures were the patients’ scores on the NIHSS ,modified Rankin Scale , Barthel Index,and Glasgow Outcome Scale at 90 days After treatment . After this trail , Lampl et al.（2007）concluded the NEST-1 study indicates that NLS therapy has shown initial safety and Effectiveness for the treatment of ischemic stroke in humans when Demonstrate safety and effectiveness is warranted.

Cerebral infarction is just a kind of stroke . Qiao et al.（2004） Have treated 68 patients with cerebral infarction with LHNL at 10~ 15mW for 60 min each time,which was done once a day and ten days each session for given sessions how much of which depended the patient aymptom but it was at best 3 sessions,and found the symptom improvement of 34（50.5%），27（39.7%）and 7（10.3%）patients eere significant , mild and none , respectively . Xiao et al.（2005） dave treated 21 and 18 patients with cerebral infarction by ILILT with LGAL at 3.5~4.0mW for 30 min and ILELT with GaInP/AlGaInP diode laser irradiation at 650nm at 2.5~3.0mW for 30 min, respectively , and the single photon emission computed tomography （SPECT）in brain perfusion imaging indicated the ratio of local regional cerebral blood flow（rCBF）vs whole brain Rcbf and brain blood flow function change rate（BFCR%）increased in the focus side of the b rain after treatment of either ILILT or ILELT , but no change in the mirror regions and no significant difference between ILILT and ILELT. Li et al.（1999a）have treated 40 patients with cerebral Thrombosis withLHNL at 3.5~4.5mW for 30 min each time , which Was done once a day and five days each session for two sessions Between which there were two days for rest , and found malformation Rate of erythrocytes decreased.

Dou et al.（2003）randomly divided 60 patients with cerebral Infarction and 36 patients with traumatic brain injury into two Groups , 50 in ILILT group and 46 in ILELT group,and then treated ILILT group with LGAL at 2.4mW for 40 min each time and ILELT group with He-Ne laser at 2.5mW for 40 min each time,respectively, which were done once a day and five days each session for two sessions between which there were two days for rest,and found the cholesterol , TG , LDL-C , erythrocyte sedimentation rate and hematocrit were significantly reduced,Fugl Meyer movement scale and Barthel index scores were significantly increased and the brain damage are