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Biomedical subjects

Gerhard Litscher

Publications and source records attributed to Gerhard Litscher.

15 recordsLinked to original sources
PubMed2006

Electroencephalogram--entropy and acupuncture.

Computer-based measuring of the level of sedation and hypnosis is difficult and has proven to be challenging. The electroencephalogram (EEG) has been proposed as a potential method. Response entropy (RE) and state entropy (SE) are multifactor, dimensionless parameters of a new technology of EEG monitoring, and we investigated them for the first time in acupuncture research within this study. Both parameters have been alleged to reflect changes in the clinical state of sedation. Two different acupuncture schemes were tested in a randomized crossover trial with nine healthy volunteers (mean age +/- sd, 28.8 +/- 3.6 yr; 25-36 yr). Applying and stimulating acupuncture needles or performing laserneedle acupuncture at special sedation points decreased RE and SE significantly (P < or = 0.01; paired t-test) compared with the reference interval before acupuncture. In contrast, acupuncture of points for increasing "Qi-energy" did not decrease parameters of entropy. Specific acupuncture schemes produce specific, reproducible, and quantifiable effects on entropy parameters in the EEG. Therefore, entropy measurements during acupuncture seem to be worthy of further evaluation with a larger series of subjects.

Acupuncture Points↗
PubMed2006

Bioengineering assessment of acupuncture, part 1: thermography.

In Western society, acupuncture is becoming a popular complementary method to medical treatment. However, a scientific understanding of acupuncture has not been completely developed but will absolutely be necessary for the increased acceptance of acupuncture by the Western medical community. This first part of the review article describes, in a general introduction, milestones of acupuncture research within the last 30 years and in a specific part the possibilities and limitations of infrared thermography, a noninvasive biomedical engineering method, within acupuncture research.

Acupuncture Therapy↗
PubMed2006

Bioengineering assessment of acupuncture, part 2: monitoring of microcirculation.

In the second part of the review article, monitoring of microcirculation during acupuncture is described. Laser Doppler flowmetry and laser Doppler imaging provide easy-to-use, noninvasive, real-time measurements of local tissue blood flow. Using these types of biomedical equipment, it is possible to quantify and objectify peripheral changes in microcirculation during different methods of acupuncture stimulation (manual needle acupuncture and laserneedle acupuncture).

Acupuncture Therapy↗
PubMed2006

Bioengineering assessment of acupuncture, part 3: ultrasound.

Multidirectional transcranial ultrasound monitoring can be used to prove quantifiable effects of acupuncture stimulation in the brain. This third part of the review article gives a short introduction in monitoring cerebral blood flow velocity and summarizes the scientific results in this area of research. New constructions from the Medical University of Graz that can be used for evidence-based computer-controlled acupuncture are described. With these new methods and concepts, reproducible effects of needle and laserneedle acupuncture stimulation in cerebral blood flow velocity can be objectified for the first time.

Acupuncture Therapy↗
PubMed2006

Bioengineering assessment of acupuncture, part 4: functional magnetic resonance imaging.

In the fourth part of this review article, research on the topic of acupuncture and functional magnetic resonance imaging is described. Needle as well as painless laserneedle stimulation have led to significant changes in different areas of the brain. With the help of modern biomedical engineering equipment and neuroscience, some of acupuncture's secrets have begun to be revealed. The neuro-modulating effects require further investigation in a larger population sample.

Acupuncture Therapy↗
PubMed2005

[Increases of intracranial pressure and changes of blood flow velocity due to acupressure, needle and laser needle acupuncture?].

BACKGROUND: Pressure on the acupoints St.7 and SJ.22 can lead to significant, reversible increases in intracranial pressure (ICP) in patients with elevated ICP. OBJECTIVE: In this study, we investigated whether changes in cerebral parameters in healthy volunteers can also be registered, when the mentioned acupoints associated with ICP, are stimulated. SUBJECTS AND METHODS: We investigated a total of 34 volunteers (24 females, 10 males) and a 15-year-old intensive care patient after severe head injury. The mean age of volunteers was 25.2 +/- 3.4 years (range 20-35). Stimulation was performed using acupressure techniques, manual needle and laser needle methods. We evaluated the main parameter of mean blood flow velocity in the middle cerebral artery (left and right) as well as the pulsatility index. In addition, near infrared spectroscopy and blood pressure parameters were registered. RESULTS: Acupressure, manual needle acupuncture and laser needle acupuncture partially led to significant changes in the main goal values. CONCLUSION: Acupressure as well as acupuncture (needle and laser needle) can evoke reproducible functional changes in the brain. These accompanying effects are not to be ignored, in particular in patients with increased ICP.

Acupressure↗
PubMed2005

Infrared thermography fails to visualize stimulation-induced meridian-like structures.

BACKGROUND: According to Traditional Chinese Medicine (TCM) the vital energy flows through a system of channels also called meridians. Generally accepted proof for meridians cannot be considered as being given. Goal of this study was to examine whether possible stimulation-induced meridian-like structures, as recently described by other authors, can be visualized and objectified simultaneously at different infrared wavelength ranges. METHODS: The study analyses evidence for the existence of acupuncture-specific, meridian-like artifacts in 6 healthy volunteers (mean age +/- SD 28.7 +/- 3.7 years; range 25 - 35 years). Two infrared cameras at different wavelength ranges were used for thermographic control of possible stimulation effects (moxibustion-cigar, infrared warmth stimulation, needle and laserneedle stimulation). In addition to thermography, temperature and microcirculatory parameters were registered at a selected point using laser-Doppler flowmetry. RESULTS AND CONCLUSION: After moxibustion (or infrared light stimulation) of the body at 2 - 5 microm and 7.5 - 13 microm ranges, different structures appear on thermographic images of the human body which are technical artifacts and which are not identical to what are known as meridians in all textbooks of TCM. Further scientific studies are required regarding the possible visualization of meridians.

Acupuncture Points↗
PubMed2005

An NIRS matrix for detecting and correcting cerebral oxygen desaturation events during surgery and neuroendovascular procedures.

BACKGROUND: Transcranial cerebral oximetry was developed for early detection of cerebral hypoxia and to avoid cerebral dysfunctions. However, near infrared spectroscopy (NIRS) data obtained during surgery are subject to intrinsic and extrinsic influences that have to be accounted for when interpreting the recordings. METHODS: We developed an NIRS matrix to provide brief information for specific intervention to correct changes of cerebral oxygen saturation (COS). Selected vital data and the descriptors of cerebrovascular and neurofunctional status were linked to logistic chains. RESULTS: The matrix is horizontally and vertically grouped and contains five descriptors: 1. change of COS; 2. key variable (parameter related to the change of COS); 3. associated parameters (vital data that do not cause COS alterations); 4. interpretation of values or preconditions most probably due to COS changes; and 5. the intervention most likely to normalize the COS or return it to baseline. The descriptors are grouped horizontally to a logistics chain. CONCLUSION: The modular expandable NIRS matrix we describe has promise for clinical use in surgical, neurointerventional, and anaesthesiological contexts.

Adult↗
PubMed2004

Pseudoparadoxical dissociation of cerebral oxygen saturation and cerebral blood flow velocity after acupuncture in a woman with cerebrovascular dementia: a case report.

Acupuncture can increase both cerebral oxygen saturation and cerebral blood flow velocity. We describe a 77-year-old woman with cerebrovascular dementia in whom acupuncture reproducibly induced an increase of blood flow velocity but a decrease of regional oxygen saturation. At four of 11 acupuncture sessions, blood flow velocity was measured in the middle cerebral artery with transcranial Doppler sonography and cerebral regional oxygen saturation (rSO(2)) with transcranial near infrared spectroscopy. Cerebral blood flow velocity increased by an average of 20% (range: 7-27%) at all four study points whereas rSO(2) consistently decreased by an average of 7% (range: 4-13%). Clinical status and cognitive function improved. These findings in a patient with vascular dementia may suggest increased oxygen extraction by activated neuronal structures.

Acupuncture↗
PubMed2004

Objectivation of cerebral effects with a new continuous electrical auricular stimulation technique for pain management.

AIMS: The electrical point stimulation system (P-STIM) reflects a new, miniaturized system for pain therapy through ear acupuncture. For this reason, ultrathin needles were applied at the ear. The needles stimulate the acupuncture areas at the ear using electrical impulses, which come from a little generator applied behind the acupunctured ear. METHODS: This study describes continuous, non-invasive measurements of near infrared spectroscopy (NIRS) and multidirectional transcranial Doppler sonography in two healthy females (aged 23 and 27 years) during stimulation with P-STIM, for the first time. RESULTS: The results of the pilot measurements have shown that electrical point stimulation using the new electrical stimulation system on eye acupuncture points is able to modulate the mean blood flow velocity (vm) of the supratrochlear artery. These effects were present using a stimulation frequency of 100 Hz. A lower increase in vm was found in the middle cerebral artery. In addition, stimulus induced, quantifiable and reproducible alterations of the regional cerebral NIRS parameters were be detected. CONCLUSION: For the first time, P-Stim allows intermittent ear acupuncture stimulation for up to several days in combination with complete mobility for the patient.

Acupuncture Points↗
PubMed2003

Noninvasive assessment of cerebral oxygenation during high altitude trekking in the Nepal Himalayas (2850-5600 m).

Mountain trekking is significantly increasing in popularity. Hypoxia seems to play a key role in the pathogenesis of acute mountain sickness (AMS). The purpose of this study was to investigate regional cerebral (rSO2) and peripheral (SaO2) oxygen saturation for the first time, during 22 days high altitude trekking (measurement points: 3450, 4450, 4750, 5050 and 2850 m) in the Khumbu region of Nepal with near infrared spectroscopy and pulse oximetry. We examined 17 healthy volunteers 19-65 years old (8 female, 9 male; mean age +/- SD, 46.1 +/- 13.1 years). RSO2 and SaO2 were significantly (p < 0.001, ANOVA, Tukey test) decreased at high altitudes (4450, 4750 and 5050 m). The decrease in cerebral oxygen saturation was more pronounced at higher altitudes than in the periphery (rSO2/SaO2 = 0.56 at 5050 m). At higher altitudes (> 4450 m), two subjects showed reversible symptoms of AMS. The present data indicates that acute reduction in rSO2 values might be a primary cause of AMS, however, further studies and analysis are necessary to correlate our findings with cerebral symptom scores.

Adult↗
PubMed2003

Cerebral and peripheral effects of laser needle-stimulation.

This study comprises scientific-theoretic fundamental investigations of laserneedle technology, a new and painless method of acupuncture stimulation. Laserneedles are not inserted in the skin, but are merely placed on the surface of the acupuncture point. The study documents the significant changes in peripheral microcirculation (p = 0.005) and surface temperature of the skin (p = 0.02) induced by laser, in 22 healthy volunteers (mean age 24.4 +/- 2.6 years). In addition, a randomised cross-over study to characterise the specific changes in cerebral blood flow velocity with laserneedle acupuncture (p < 0.001) is presented. These results provide important information for characterising the effects of laserneedle acupuncture.

Acupuncture Therapy↗
PubMed2002

Computer-based quantification of traditional chinese-, ear- and Korean hand acupuncture: needle-induced changes of regional cerebral blood flow velocity.

The purpose of this randomized, placebo-controlled, cross-over study was to investigate mean blood flow velocity (v(m)) of the ophthalmic (OA) and the middle cerebral (MCA) artery during traditional Chinese acupuncture (TCA), ear acupuncture (EA), Korean hand acupuncture (KHA) and placebo needling (PN) by simultaneous and continuous transcranial Doppler sonographic monitoring. We examined 20 healthy volunteers 19-45 years old (mean age +/- SD, 26.2 + 6.0 years). Vm in OA was significantly increased during needling vision-related acupoints of TCA (p < 0.001), EA (p < 0.05) and KHA (p < 0.05), whereas nonsignificant alterations occurred in Vm of MCA. All subjects showed insignificant changes in mean arterial blood pressure. The study design does not allow to evaluate why and how the different acupuncture methods have an effect on the brain and eye, however it proves that acupuncture can provide scientifically measurable effects.

Acupuncture Points↗