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Biomedical subjects

G Litscher

Publications and source records attributed to G Litscher.

At least 19 recordsLinked to original sources
PubMed2004

Acupuncture using laser needles modulates brain function: first evidence from functional transcranial Doppler sonography and functional magnetic resonance imaging.

Acupuncture using laser needles is a new totally painless stimulation method which has been described for the first time. This paper presents an experimental double-blind study in acupuncture research in healthy volunteers using a new optical stimulation method. We investigated 18 healthy volunteers (mean age +/- SD: 25.4 +/- 4.3 years; range: 21-30 years; 11 female, 7 male) in a randomized controlled cross-over trial using functional multidirectional transcranial ultrasound Doppler sonography (fTCD; n = 17) and performed functional magnetic resonance imaging (fMRI) in one volunteer. Stimulation of vision-related acupoints resulted in an increase of mean blood flow velocity in the posterior cerebral artery measured by fTCD [before stimulation (mean +/- SE): 42.2 +/- 2.5; during stimulation: 44.2 +/- 2.6; after stimulation: 42.3 +/- 2.4 cm/s, n.s.]. Mean blood flow velocity in the middle cerebral artery decreased insignificantly. Significant changes (p < 0.05) of brain activity were demonstrated in the occipital and frontal gyrus by fMRI. Optical stimulation using properly adjusted laser needles has the advantage that the stimulation cannot be felt by the patient (painless and no tactile stimulation) and the operator may also be unaware of whether the stimulation system is active. Therefore true double-blind studies in acupuncture research can be performed.

Acupuncture↗
PubMed2004

Effects of acupressure, manual acupuncture and Laserneedle acupuncture on EEG bispectral index and spectral edge frequency in healthy volunteers.

BACKGROUND AND OBJECTIVE: The main purpose of this study was to investigate the effects of sensory (acupressure and acupuncture) and optical stimulation (Laserneedle acupuncture) on electroencephalographic bispectral index, spectral edge frequency and a verbal sedation score. METHODS: Twenty-five healthy volunteers (mean age +/- SD: 25.5 +/- 4.0yr) were investigated during the awake state. The acupuncture point Yintang and a placebo control point were stimulated. The study was performed as a randomized, controlled and partly blinded cross-over trial. RESULTS: Bispectral index and spectral edge frequency values both decreased significantly (P < 0.001) during acupressure on Yintang to values of 62.9 (minimum 35) +/- 13.9 bispectral index and to 13.3 (minimum 2.9) +/- 8.1 Hz (spectral edge frequency right) and 13.8 (minimum 2.7) +/- 7.3 Hz (spectral edge frequency left), respectively. Bispectral index was also significantly (P < 0.05) affected by Laserneedle acupuncture and acupressure on the control point but the changes were not clinically relevant, 95.4 +/- 4 and 94.2 +/- 4.8, respectively. All interventions significantly (Yintang: P < 0.001; control point: P < 0.012) reduced verbal sedation score. CONCLUSIONS: The study highlights the electroencephalographic similarities of acupressure induced sedation and general anaesthesia as assessed by bispectral index and spectral edge frequency.

Acupressure↗
PubMed2004

[Quantification of gender specific thermal sensory and pain threshold before and after laser needle stimulation].

Quantitative thermal sensory and pain threshold testing (QST) was performed in 29 adult healthy volunteers (mean age 24.2 +/- 2.7 years; range: 18-29 years; 20 females, 9 males) using the Thermal Sensory Analyser TSA-II (Medoc Advanced Medical Systems, Ramat Yishai, Israel, and Minneapolis, Minnesota, USA) before and after laser needle acupuncture and placebo stimulation, respectively. Significant (p < or = 0,001; t-test) gender-specific differences were seen on cold pain threshold analysis. No significant changes in parameters of thermal sensory and pain thresholds were found before and after laser needle or placebo stimulation at acupuncture points for acute pain. However, a trend towards change in the median value of cold pain sensation after laser needle stimulation (p = 0.479; paired t-test; n.s.) was seen within the group of healthy females. The influence of stimulation of acupuncture points for chronic pain on the various parameters needs to be clarified in future studies.

Acupuncture↗
PubMed2002

Changed skin blood perfusion in the fingertip following acupuncture needle introduction as evaluated by laser Doppler perfusion imaging.

Rapidly repeated imaging of the left middle fingertip skin blood perfusion was performed in 51 healthy volunteers (mean age +/- SD: 25.3 +/- 7.6 years) prior to, immediately after and in the early reperfusion phase following introduction of an acupuncture needle at the Neiguan point (Pe. 6) and at a placebo point respectively, using a Laser Doppler Perfusion Imager (LDPI). The average skin perfusion of the fingertip was calculated for each image and used as an indicator of the microvascular response to the acupuncture needle introduction. The results of this randomised, placebo-controlled, cross-over study showed significant differences (p < or = 0.001) in the immediate skin blood perfusion response when needling is performed in an acupuncture point (Neiguan) and a placebo point, with a more pronounced reduction in skin blood perfusion when needling the acupuncture point. In the early reperfusion phase, however, a substantial increase in skin perfusion was observed that amounted to about 18% of the level prior to needle introduction, irrespective of the site of needle application. In a single individual it was demonstrated that the vasodilatation following needling in the acupuncture point persisted for a more extended time period. These results suggest that the LDPI technology may be useful in visualising and quantifying the peripheral vascular effects of acupuncture on the microcirculation.

Acupuncture↗
PubMed2002

Cerebral vascular effects of non-invasive laserneedles measured by transorbital and transtemporal Doppler sonography.

Laserneedles represent a new non-invasive optical stimulation method which is described for the first time in this paper. We investigated 27 healthy volunteers (mean age+/-SD: 25.15+/-4.12 years; range: 21-38 years; 14 female, 13 male) in a randomised cross-over trial to study differences between laserneedle acupuncture and manual needle acupuncture in specific cerebral parameters. Mean blood flow velocity ( v(m)) showed specific and significant increases in the ophthalmic artery during laserneedle stimulation ( p=0.01) and during manual needle stimulation ( p<0.001) at vision-related acupoints. At the same time insignificant alterations in v(m) were found in the middle cerebral artery for both acupuncture methods. The eight laserneedles used in this study were arranged at the end of the optical fibres. Each fibre was connected to a semiconductor laser diode emitting at 685 nm with a primary output power of about 55 mW. Optical stimulation using properly adjusted laserneedles has the advantage that the stimulation can hardly be felt by the patient and the operator may also be unaware of whether the laserneedle system is active, and therefore true double blind studies in acupuncture research can be performed.

Acupuncture Points↗
PubMed2002

[Changes in cerebral near infrared spectroscopy parameters during manual acupuncture needle stimulation].

Near-infrared spectroscopy (NIRO 300, Hamamatsu Photonics, Japan) was used to monitor human cerebral function in the central region during manual acupuncture needle stimulation of the large intestine 4 (LI.4) point in 16 adult volunteers (9 females, 7 males; mean age 23.9 +/- 6.0 (SD) years, range 19-45 years). We found a significant (p < 0.001) decrease in oxyhaemoglobin after needle insertion and stimulation (duration 20 sec.), accompanied by an increase (p = 0.003) in deoxyhaemoglobin. A repeat stimulation showed similar effects. Cytochrome oxidase aa3 remained unchanged during stimulation. The results demonstrate that near-infrared spectroscopy may be a noninvasive method of measuring regional changes in cerebral haemodynamics resulting from peripheral acupuncture stimulation.

Acupuncture Points↗
PubMed2001

Laser doppler flowmetry in combined needle acupuncture and moxibustion: a pilot study in healthy adults.

Laser Doppler flowmetry (LDF) (DRT 4/Moor Instruments Ltd, Devon, UK) was used in this pilot study for monitoring the effects of an invariable acupuncture pattern on microcirculation of the skin before, during, and after combined needle acupuncture and moxibustion in 12 healthy volunteers (mean age 35.2 +/- 4.4 years, range 26-41 years, four female and eight male). According to the standards of traditional Chinese medicine (TCM), this acupuncture pattern is assumed to be unspecific and non-therapeutic. Flux decreased during the treatment period (p<0.05) compared to the control phase before combined needle acupuncture and moxibustion. After the removal of the needles, flux did not return to the initial control value. No significant differences between mean arterial blood pressure, heart rate, skin temperature or gender were detected. A prediction of individual incidences and kinds of acupuncture effects in our healthy volunteers was not possible. Modern monitoring techniques like LDF could be a method to separate responders from non-responders to acupuncture in peripheral microcirculatory disorders. Further studies on patients with peripheral microcirculatory disorders are necessary in order to demonstrate the value of LDF in detecting responders/non-responders in combination with therapeutic acupuncture patterns according to TCM.

Acupuncture↗
PubMed2001

Effects of QiGong on brain function.

QiGong is an ancient and widely practiced Chinese meditation exercise. We studied the effects of QiGong on brain function with modern neuromonitoring tools in two subjects. In a male QiGong master (extremely trained practitioner), the technique induced reproducible changes in transcranial Doppler sonography, EEG, stimulus-induced 40 Hz oscillations, and near-infrared spectroscopy findings. Similar effects were seen after the application of multimodal stimuli and when the master concentrated on intense imagined stimuli (e.g. 22.2% increase in mean blood flow velocity (vm) in the posterior cerebral artery, and a simultaneous 23.1% decrease of vm in the middle cerebral artery). Similar effects were seen in the female subject. Neuromonitoring during QiGong appears able to objectify accompanied cerebral modulations surrounding this old Chinese meditation exercise.

Acoustic Stimulation↗
PubMed2001

Effects of popliteal illumination on cerebral near-infrared spectroscopy.

The endogenous clock of humans can be influenced by light application to the popliteal region. Previously, it had been assumed that light must fall directly into the eye in order to influence the inner circadian clock. This study, published in 1998, has not been reproduced. We investigated the effects of laser light illumination (785 nm for 5 min) on cerebral near infrared spectroscopy (NIRS) in 33 volunteers. There were significant (p < 0.001) delayed (2 min) alterations in NIRS parameters during popliteal light illumination. This could be further evidence for extraocular phototransduction in humans.

Adult↗
PubMed2001

[Laser Doppler imaging and cryoglobulinemia].

Continuous microcirculation monitoring of the right foot was carried out for the first time in a 62-year-old patient with cryoglobulinaemia prior to, during and after manual needle insertion at Jie Xi(St.41) acupuncture point using a new method of laser Doppler perfusion imaging (PIMII, Lisca AB, Linköping, Sweden). In addition to visual inspection, changes in mean perfusion were also used as evaluation parameters. Our results suggest that the new biomedical technique of laser Doppler imaging is a useful method for monitoring the effects of acupuncture on the peripheral microcirculation.

Acupuncture Therapy↗
PubMed2000

The influence of positioning on spectroscopic measurements of brain oxygenation.

This study was designed to evaluate the influence of body position during neurosurgical and cerebrovascular operations on regional cerebral oxygen saturation (rSO2). Awake volunteers (group I; n = 14), anesthetized patients (group II; n = 48) undergoing lumbar discectomy, and 12 patients undergoing carotid endarterectomy (group III) with internal carotid artery (ICA) stenosis were studied. Anesthesia in the patient groups was performed with sevoflurane (1.1 Vol% insp.) in N2O2/O2 mixture (FiO2 0.4) rSO2 was monitored with a INVOS 4100 cerebral oxymeter (Somanetics Corporation, Troy, MI). Measurements were done in all groups in supine position with head turned to the right and left side. Furthermore, in groups I and II, rSO2 was measured in right lateral, left lateral, prone, or sitting position. In each position the parameters were registered at three times (1, 3, and 5 min after taking up the position). In the healthy volunteers, the mean rSO2 values of both hemispheres were 71.3 +/- 5.0%. No significant changes of rSO2 were found interhemispherical and upon turning the head to both sides or positioning to the prone and both lateral positions. After assuming the sitting position, the decrease of rSO2 was not significant. In group II, rSO2 decreased significantly in the sitting position. In group III, baseline readings for rSO2 obtained from the side of ICA stenosis were significantly lower, compared to the contralateral side. After turning the head to the ipsilateral side, this difference diminished. In contrast, turning the head toward the contralateral side, the rSO2 difference remained nearly constant, both values decreasing constantly throughout the observation period. In conclusion, after different positioning maneuvers awake and under anesthesia, alterations of rSO2 can be registrated by near-infrared spectroscopy (NIRS).

Adult↗
PubMed1999

Ultrasound-monitored effects of acupuncture on brain and eye.

A new transcranial Doppler sonography arrangement was used to monitor blood flow profiles in the supratrochlear and middle cerebral arteries simultaneously and continuously. The technique selectively demonstrated the specific effect of acupuncture on the cranial arteries, in a 25-year-old female with pigmentary retinopathy. Stimulation of points Zanzhu and Yuyao led to a marked increase of blood flow velocity in the supratrochlear artery and to a decrease of flow velocity, in the middle cerebral artery. These acupuncture-induced effects were reproducible even though both arteries originate from the same major vessel.

Acupuncture Therapy↗
PubMed1999

Computer-controlled acupuncture. Quantification and separation of specific effects.

The effects of acupuncture have been described and handed down empirically for centuries but there are few reports based on objective data. The aim of this study was to provide selective evidence of a specific effect of acupuncture on the brain and the eye using a Doppler ultrasound technique. A transcranial Doppler sonography arrangement was developed to monitor blood flow profiles in the supratrochlear and middle cerebral arteries simultaneously and continuously. Two acupuncture schemas were tested in a randomized cross-over study with 13 patients with ophthalmologic diseases. Applying acupuncture needles to special eye points increased the blood flow velocity in the supratrochlear artery significantly (p < 0.001) compared to the reference interval before acupuncture. In the middle cerebral artery only a minimal, non-significant increase in blood flow velocity was seen. In contrast, acupuncture of points that are held to increase cerebral blood flow velocity increased blood flow velocity in the middle cerebral artery significantly (p < 0.001) while leaving that in the supratrochlear artery unchanged. Specific acupuncture produce specific, reproducible quantifiable effects on blood flow velocity in arteries to the brain and eye.

Acupuncture Therapy↗
PubMed1999

Is there paradoxical arousal reaction in the EEG subdelta range in patients during anesthesia?

Different anesthetic drugs can produce different electroencephalographic (EEG) patterns. Nondrug induced influences, such as surgical stimulation, may also alter the EEG in anesthetized patients. Increases of delta activity are interpreted as signs of deepening of anesthesia. These EEG patterns are sometimes also found in frontal leads after surgical stimulation during isoflurane anesthesia. However, to avoid incorrect anesthetic management under EEG monitoring, this phenomenon of "paradoxical arousal" must be taken into consideration. This study demonstrates that, after surgical stimulation, frontal activity was enhanced in the 2-3 Hz and 3-4 Hz frequency bands. On the other hand, in the subdelta range (the 0.05-1 Hz and 1-2 Hz frequency bands), there was an opposite reaction. This significant (p<0.001, according to ANOVA and Dunn's method) reduction of EEG power as a result of the surgical stimuli was found in 25 patients (mean age, 49.1+/-16.3 years) scheduled for elective neurosurgical intervention in the lumbosacral region. This report shows some of the problems arising from the common practice of arbitrarily subdividing a power spectrum in frequency bands.

Adolescent↗
PubMed1999

[Computer-controlled acupuncture. A new construction for simultaneous measurement of blood flow velocity of the supratrochlear and middle cerebral arteries].

Acupuncture has been used for over 5,000 years and a large body of evidence exists. Transcranial Doppler (TCD) ultrasound, introduced more than a decade ago, has evolved into a dynamic, reliable, reproducible and practical diagnostic tool. In this study we describe simultaneous and continuous TCD monitoring of the supratrochlear and middle cerebral arteries in two patients with ophthalmologic diseases undergoing computer-controlled acupuncture (CCA). During eye acupuncture scheme there was a significant increase in the mean bloodflow velocity (vm) of the A. supratrochlearis (+39% patient 1; +15% patient 2; p < 0.001, t-test) in both patients. The effect was still evident after the needles were removed. There was a smaller increase (+4% and +3%; n.s.) of vm in the A. cerebri media. These results suggest that eye acupuncture could have a specific effect on intra- and extracerebral arteries. CCA might improve the quality of acupuncture.

Acupuncture Therapy↗
PubMed1999

[Thermographic visualization of changes in peripheral perfusion during acupuncture].

Using infrared thermography, the present study evaluated the effects of changes in peripheral perfusion occurring during the initial phase of manual acupuncture (Nei Guan, Qu Chi) under standardised conditions. Thermographic recordings (AGEMA 570 PRO, Flir Systems Inc., Portland, USA) were used to assess superficial changes in temperature in the hands of 6 normal subjects (mean age 33.3 +/- 7.5 years, 3 females, 3 males). Baseline status, acupuncture needling and stimulation were analysed in a single session under controlled conditions (24 degrees C ambient temperature). In all subjects a significant (p = 0.015) short-term cooling effect on superficial hand temperature occurred following needle placement. Thereafter, acupuncture stimulation produced different generalised long-lasting effects. In three subjects a warming effect was seen (increase > 2 degrees C) while in the other three subjects the temperature decreased in all fingers and in the wrist.

Acupuncture Therapy↗