Application of near infrared spectroscopy in monitoring blood oxygen saturation of fibula flaps / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the change of tissue oxygen index (TOI) by non-invasive near infrared spectroscopy (NIRS) and to investigate the blood flow variety of fibula flaps after operation.</p><p><b>METHODS</b>Thirty-six patients who accepted fibula flap reconstruction were chosen as subjects. Authors measured the TOI of the fibula flaps and the control side every four hours in the first twenty-four hours, and measured these positions with the intermittence of twelve hours from second to eighth day after operation.</p><p><b>RESULTS</b>Thirty-five flaps were successful and one failed. The TOI of fibula flaps shortly after operation was significantly lower than that before the operation( P<0.05). In the successful cases the TOI of fibula flaps and the control sides was fluctuated from 50.0% to 72.0%. The TOI of fibula flaps was significantly lower than that of the control sides within 144 hours after operation(P<0.05). After 144 hours the TOI was equal to that of the control side. TOI of the failed case decreased dramatically.</p><p><b>CONCLUSIONS</b>NIRS can reliably indicate the change of TOI in buried flaps and detect ischemia at the early stage. The TOI of the fibula flaps depress at the early stage and returns to normal at 144 hours after operation.</p>

Correlation of brain hypoxia at different degrees with brain function and brain damage investigated using near infrared spectroscopy / 中华儿科杂志

<p><b>OBJECTIVE</b>To study correlation of brain hypoxia of different degrees with brain function and damage.</p><p><b>METHODS</b>The brain regional oxygen saturation (rSO2) was determined by using a non-invasive near infrared spectroscopy (NIRS) technique in 15 piglets; the piglets were subjected to inhale 3% - 11% oxygen-nitrogen mixed gas through mechanical ventilation for 30 min. The piglets were divided into groups according to the level of brain rSO2 (i.e. < 30%, 30% - 35%, 35% - 40%, and 40% - 50%), and the data were compared with those of the control group (rSO2 > 60%). Changes of brain function were detected through amplitude and frequency of EEG waves and signal complexity. The piglets were sacrificed via decapitation 72 h after brain damage, and then histopathological and ultrastructural examinations were performed on cerebral cortex and hippocampal CA1 area.</p><p><b>RESULTS</b>In the group with rSO2 > 40%, the mean arterial pressure (MAP) after hypoxia was (56 +/- 0.00) mm Hg (1 mm Hg = 0.133 kPa), the blood lactic acid (LA) was (2.3 +/- 1.2) mmol/L, the EEG findings were within normal range, and there was no change in brain tissue ultrastructure. In the group with brain rSO2 = 30% approximately 40%, the MAP was (73 +/- 8) mm Hg, the LA was (8.2 +/- 3.9) mmol/L, the EEG waves showed decreased amplitude, frequency and complexity, but restored to some extent after hypoxia. The brain tissue ultrastructure showed damages to the cerebral cortex and neuron mitochondria at hippocampal CA1 area. In the group with brain rSO2 < 30%, the MAP was (35 +/- 0) mm Hg, the LA was (12 +/- 2) mmol/L, the EEG showed decreased amplitude, frequency, and complexity of signals compared with those of the normal control group, and was difficult to restore after hypoxia in some of the piglets; the brain tissue ultrastructure appeared to be similar to the changes seen with high-degree swollen cerebral cortex and neuron mitochondria at hippocampal CA1 area.</p><p><b>CONCLUSION</b>Different degrees of hypoxia had different influence on brain function and brain damage. The lower the brain rSO2, the more severe the damages to the brain and its function. The rSO2 of brain tissues detected with noninvasive NIRS can reflect brain injury and its severity during cerebral anoxia.</p>

Evaluation of early cognitive ability of infants born preterm by near-infrared spectroscopy / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To compare the differences in cerebral oxygenation responses between the infants born preterm and full-term infants and to evaluate the early cognitive ability of infants born preterm.</p><p><b>METHODS</b>Cerebral oxygenation after light stimulation was detected by near infrared spectroscopy (NIRS) in preterm infants at 3 or 6 months corrected gestational age (GA). The results were compared with those of age-matched infants born at term.</p><p><b>RESULTS</b>The start and peak response time of cerebral oxygenation occurring after light stimulation in preterm infants at 3 months corrected GA was 17.2 +/- 5.2 and 38.4 +/- 9.6 seconds respectively, which were significantly longer than in age-matched term infants (13.1 +/- 2.7 and 28.9 +/- 5.0 seconds respectively) (P < 0.05). The maximum response value of hemoglobin, oxyhemoglobin and regional oxygen saturation of the preterm infants at 3 months corrected GA was (1.2 +/- 0.5)%, (1.5 +/- 0.6)%, and (1.3 +/- 0.4)% respectively , which were significantly lower than that of the term infants [(2.3 +/- 0.3)%, (2.8 +/- 0.3)% and (2.4 +/- 0.5)% respectively] (P < 0.05). Cerebral oxygenation responses to light stimulation in preterm infants examined at 6 months corrected GA were not significantly different from age-matched term infants.</p><p><b>CONCLUSIONS</b>Cerebral oxygenation responses to light stimulation in infants born preterm at 3 months corrected GA are not as good as age-matched term infants, but were close to the level of age-matched term infants at 6 months corrected GA. This suggests that the early cognitive ability of preterm infants before 3 months corrected GA might fall behind age-matched term infants.</p>

Evaluation of relationship between early brain response and neurodevelopment in newborns by using near infrared spectroscopy / 中华儿科杂志

<p><b>OBJECTIVE</b>To study the relationship between early brain response to extrinsic stimulation and neurodevelopment in preterm infants, assess the brain function of preterm infants in the early stage, and thereby to provide objective evidence for the degree of neurodevelopment in preterm infants and to evaluate prognosis.</p><p><b>METHODS</b>Using near infrared spectroscopy (NIRS), the brain response to sound stimulation of 90 preterm infants at different gestational age was observed and compared with the result obtained from 20 full term infants. The neonatal behavioral neurological assessment (NBNA) was performed at corrected age of 40 weeks, and the infants were followed up for 2 years. The effect of gestational age and brain damage on preterm infants, the relation between early brain response in preterm infants and their neurodevelopment was evaluated.</p><p><b>RESULTS</b>All the preterm infants responded to different degrees to auditory stimulation after birth. The time to beginning to react and the time to appearance of the peak reaction were attained after auditory stimulation and the time to beginning to resume when the auditory stimulation was stopped was (278 +/- 94) s, (446 +/- 67) s and (199 +/- 52) s, respectively, which were significantly longer than those observed in the full term infants (107 +/- 30) s, (264 +/- 51) s and (131 +/- 46) s, respectively. The maximum reactions of hemoglobin, oxyhemoglobin and regional oxygen saturation in the infants after gestational age 32 weeks was (0.3 +/- 0.3)%, (0.7 +/- 0.5)% and (0.3 +/- 0.3)%, respectively, which were significantly lower than those in the full term infants (1.7 +/- 0.7)%, (1.7 +/- 0.8)% and (1.6 +/- 0.7)%, respectively. When the brain response of preterm infants was compared with that in infants without brain damage, the speed of the reaction was slow, the maximum reaction was low. The brain response in preterm infant was correlated with NBNA at corrected age of 40 weeks. It was found during the following-up that abnormal neurodevelopment was associated with poor brain reaction.</p><p><b>CONCLUSIONS</b>NIRS can be used to evaluate brain response of infants. Preterm infants display brain response to auditory stimulation. Early brain response is correlated with neurodevelopment.</p>

Regional cerebral oxygen saturation in neonates with meconium aspiration syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>This study examined the changes of regional cerebral oxygen saturation (rSO2) by noninvasive near infrared spectrophotometry in neonates with meconium aspiration syndrome (MAS).</p><p><b>METHODS</b>Seventy-three full neonates with MAS were divided into three groups by respiratory symptoms: asymptomatic group (group 1, n=38), common group (group 2, n=28) and severe group (group 3, n=7). Near infrared spectrophotometry was used to measure the cerebral rSO2 on days 1, 3, 5 and 7 after birth. Thirty healthy full-term newborns served as the Control group.</p><p><b>RESULTS</b>The cerebral rSO2 of group 1 decreased significantly compared with that of the Control group between days 1 and 3 (P < 0.05). The cerebral rSO2 of group 2 or group 3 was significantly lower than that of group 1 and the Control group on days 1, 3 and 5 (P < 0.05). The MAS patients with mild hypoxic-ischemic encephalopathy (HIE) had significantly higher brain rSO2 levels than those with medium or severe HIE on days 2, 3 and 5 (P < 0.05).</p><p><b>CONCLUSIONS</b>The cerebral rSO2 decreased in neonates with MAS. The values for rSO2 correlated with the severity of HIE in MAS patients.</p>

Charge couple device-based system for 3-dimensional real time positioning on the assessment of segmental range of motion of lumbar spine / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the tested results of the segmental range of motion (ROM) of lumbar spine by charge couple device (CCD)-based system for 3-dimensional real-time positioning (CCD system), and to analyze its clinical significance.</p><p><b>METHODS</b>Seven patients with lumbar joint dysfunction and 8 healthy subjects were tested twice by the CCD-based system with an interval of 10 min.</p><p><b>RESULTS</b>The ROM of the patients was obviously lesser than that of the healthy subjects. The measuring data of segmental ROM of lumbar spine by CCD system is correlated significantly to the same data checked later on the same subjects in every direction of the movements. The differences between two checks are usually less than 1 degree.</p><p><b>CONCLUSION</b>Specially designed CCD based system for 3-dimensional real-time positioning could objectively reflect the segmental ROM of lumbar spine. The system would be of great clinical significance in the assessment of the biomechanical dysfunction of lumbar spine and the effect of the treatment applied.</p>