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Meridian therapy: current research and implications for critical care.

The National Institutes of Health recently recommended further research on the efficacy of acupuncture and allocated Federal funds to stimulate clinical studies. Their decision was based on a growing body of successful research outcomes in which acupuncture was used in the treatment of acute and chronic pain, nausea, circulatory functions, and mood-related behavioral disorders. Despite a burgeoning body of clinical research, the ability to generalize findings has been affected by design flaws, sample type and size, and multiple methods of acupuncture site stimulation. Complicating the communication of findings is use of the term acupuncture when other strategies are used to stimulate the point, such as electrical probes and low-intensity laser. A more appropriate term for acupuncture is meridian therapy, because it encompasses all methods used to treat an acupoint. The purpose of this article is to define meridian therapy with a focus on current clinical perspectives, to review research outcomes in areas important to the care of critically ill patients, to identify issues related to the application of meridian therapy in the clinical arena, and to elaborate practitioner preparation and licensure requirements.

Acupuncture Therapy↗

The influence of acupuncture on the impedance measured by four electrodes on meridians.

The impedance on the pericardium merdian near Quze (P3) and control points in 12 cases was measured by a four electrodes impedance instrument. The amplitude of impedance was recorded before, during and after needling the Neiguan. The result showed that the mean impedance on the meridian and control points before the needling were 52.8 +/- 11.0 (omega) and 61.7 +/- 10.3 (omega) respectively which had significant difference (P<0.05). During the needling, impedance decreased significantly on the meridian by 9.2 +/- 5.6 (omega) (P<0.001) while impedance decreased by only 0.12 +/- 2.4 (omega) on control points without significance (P>0.05). The impedance changed back to 51.1 +/- 11.3 (omega) and 59.9 +/- 11.0 (omega) on the meridian and control points respectively during the 5-10 minutes after withdrawing the needling. In some cases, impedance changed intermittently during the needling. The experiment implies that interstitial fluid increases during the needling by axon reflection and blood capillary expanding which may be one of the mechanisms of acupuncture regulation.

Acupuncture Therapy↗

[Preliminary observation of imaging of facial temperature along meridians].

Visualization of meridians has been carried out by means of infrared thermography and radionuclide scintigraphy, but real success was hardly achieved on some special regions including facial channels. In this paper, we would represent some imagings of thermal line along channels by means of infrared thermography. Distribution of the facial temperature in 139 cases of healthy volunteers and 305 cases of patients with facial paralysis was observed with model AGA-782 infrared thermovision and TC-800 computer. In all cases of patients and 15 cases of healthy persons, acupuncture test was conducted. Special program, DISCO3.1 was used to process the thermographic data and the results were as follows: 1. Facial thermal line along channel was presented in 95 out of 444 cases. High temperature line along bladder channel appeared in 34 cases of them; 2. In 26 out of 95 cases, the thermal line appeared after acupuncture, which could improve the imaging of the line; 3. The range of the temperature was within 1.3 degrees C, in some cases only 0.2-0.3 degrees C, with +/- 0.5-1.0 degrees C difference to surrounding temperature; the width of the line was 1-1.5 cm in most cases; 4. The line could appear stably, in some cases, last for several days, weeks or months; 5. Certain relationship between the appearing of the line and facial paralysis was found. As mentioned above, the thermal characteristics of meridians in face could be visualized by means of infrared thermography, the special imaging of facial temperature along bladder meridian was easily found, related to facial troubles and promoted by acupuncture.

Acupuncture Therapy↗

[The experimental research of Atractylodes macrocephala and Poria cocos on the meridian tropism theory in animals].

OBJECTIVE: The research was designed to study the meridian tropism theory of traditional Chinese drug through experiments in animals. METHOD: We used the mouse model of deficient spleen as the object. After administering Atractylodes macrocephala and Poria cocos respectively, we measured the indexes of MDA, SOD, NO to observe the effects of the drugs on various organs and compared the results with the traditional meridian tropism theory. RESULT: The two drugs had selective effects on the quantity or activity of MDA, SOD, NO in the organs for the normal group and the model group. CONCLUSION: The selective influence of the two drugs has close relativity with the traditional meridian tropism theory.

Animals↗

[A new way for study of meridian essence].

OBJECTIVE: To explore a new way for study of meridian essence. METHODS: Review and analyze survey of studies of meridian essence at home and abroad in the last 20 years, and introduce structural characteristics and function of the gap junction channels, hemichannels as well as some similarities with meridians. RESULTS: The effects of acupuncture are related with the nerve system, endocrine system, immune system, connective tissue, and so on. Homocellular and/or heterocellular gap junction channels, hemichannels between the heterocells and homocells may be the structural substance by which mechanical signals similar to acupuncture can be translated into bioelectrical and/or biochemical signals. CONCLUSION: The effects of acupuncture are comprehensive response of the nerve system, blood vessel system, endocrine system and immune system and other systems with the gap junction channels and hemichannel of high density as substance basis and the fluid between cells and tissues as the buffer system.

Acupuncture↗

[What's the original concept of meridian and acupuncture point in oriental medicine?--A perspective of medical history].

Meridian and acupuncture point (MAP) is a core theory of acupuncture and essential building blocks of oriental medicine. There still continue theoretic or experimental arguments and controversies on the origination or original concept of MAP, without any definite approval or disapproval of a hypothesis. The theory of MAP is an historic product and has never been outside of historic influences. This study discusses the original concept of meridian and acupuncture point theory and its historical evolution, based on the review of classic literatures on meridian including the mawangdui medical texts of Han dynasty. The concept of MAP served as a empirical reference system in clinical settings irrespective of the anatomical entity of MAP.

Acupuncture Points↗

[Effects of electroacupuncture at du meridian on contents of nitric oxide and endothelin in rats with acute cerebral ischemia].

Thirty rats were randomly assigned to three groups, control group (10 cases), acute cerebral ischemia group (10 cases) and electroacupuncture (EA) group (10 cases). The bilateral common carotid arteries were occluded, which caused sharp drop of regional cerebral bloodflow and led acute cerebral ischemia. Contents of nitric oxide (NO) and endothalin (ET) in the cerebral cortex and boold were determined in normal, during occluding and after EA of Du meridian (GV 20, GV 14) point in rats. It was found that in acute cerebral ischemia, the brain contents of NO and ET increased, the plasme level of ET elevated and serum level of NO decreased. After EA of Du meridian point, the levels of ET and NO in the brain and blood were returned significantly to normal. It is suggested that EA at Du meridian have protective effect on neural damage induced by brain ischemia. NO and ET are possibly involved in the regulative effect of EA.

Animals↗

[Electroacupuncture along meridians activating subcutaneous primary afferents in acupoints--CB-HRP tracing study].

The experiment was performed to observe the segmental distribution of sensory afferent nerves in acupoints and the influence of electroacupuncture (EA) along meridians on it. 1% CB-HRP solution (5 microliters) was injected subcutaneously at unilateral "Zusanli" or "Ruzhong" acupoint of rats. The HRP labeled cells were counted in the related spinal dorsal root ganglia (DRG). The results were as follows: the sensory nerve terminals of "Zusanli" acupoint mainly projected to the neurons of L4 and L5 DRG and that of "Ruzhong" acupoint projected to the neurons of T4, T5 and T6 DRG; sensory nerve terminals of "Zusanli" or "Ruzhong" acupoint were activated by the EA stimulation along meridians, their ability of uptaking HRP was enhanced, so the HRP labeled cells increased in the related DRG, the HRP labeled DRG segments spread. This study provides a new morphological evidence for the mechanism's explanation of propagated sensation along the meridians.

Acupuncture Points↗

Acupuncture meridians and radiotracers.

Acupuncture is frequently used and in particular for the treatment of pain. One of the cornerstones of its use, at least in Western countries, is the concept of the acupuncture meridian. Yet, their existence has never actually been proven. Recently, a report was published stating that injection of a radiotracer at an acupuncture point allows the visualization of the corresponding meridian in the shape of a radioactive path which is apparent on scintiscans. The present work confirms the appearance of radioactive paths after the injection of a radiotracer at acupuncture points. However, the cross-checks made with the method used (counting the radioactivity of the venous blood, studying radioactivity of the organs which normally take up the tracer, scintiscan study of the complete meridian paths as they are described in traditional Chinese medicine and studying the effect of venous blockade on the observed radioactive paths) show that the radioactive paths in fact correspond to vascular drainage of the radiotracer.

Acupuncture Points↗

Interpretation of visual field defects respecting the vertical meridian and not related to distinct chiasmal or postchiasmal lesions.

Hemianopia respecting the vertical meridian generally results from a disturbance in the optic chiasm or the postchiasmal visual pathway. We present five unusual patients with visual field defects respecting the vertical meridian that were not related to distinct chiasmal or postchiasmal lesions, as determined by magnetic resonance imaging (MRI). Optic neuritis, plus the influence of the testing algorithm for perimetry, was a possible cause in two cases. The symptoms of one patient with homonymous hemianopia were a functional deficit. In the two other cases, the visual field defects may have been caused by optic disc abnormalities. Although visual field defects respecting the vertical meridian, and without any evidence of distinct disease, are uncommon, neurologists and neuro-ophthalmologists should consider the differential diagnosis if MRI is negative for distinct lesions in the optic chiasm or the postchiasmal visual pathway.

Adult↗

The role of the vertical meridian in visual memory for objects.

It is widely believed that, in human and nonhuman primates, visual memories of objects are stored in the temporal lobe. Electrophysiological results in monkeys, however, indicate that when a visual scene contains two or more objects, with at least one object in each visual hemifield, neurons in the temporal lobe of each hemisphere respond only to the objects that are in the contralateral visual hemifield, and their activity is unaffected by the objects in the ipsilateral hemifield. Putting these two premises together predicts that object memory should fail, or at least suffer a substantial decrement, when an object is presented for learning and retention as part of such a scene, but crosses the vertical meridian between the learning trial and the retention test. The effect of this change should be much greater than the effect of an equal retinal translation that crosses the horizontal rather than the vertical meridian. An experiment with normal human subjects verified this prediction under conventional conditions of tachistoscopic viewing, with a single constant fixation spot. A further condition in the same experiment, however, tested the same retinal translations in a more naturalistic condition, where the retinal changes were produced by varying the position on the display screen of the fixation spot rather than of the objects. Here, there was no significant special effect of crossing the vertical meridian. We conclude that visual memories are not stored exclusively in the temporal lobe.

Adult↗

Interconverting the matrix and principal meridional representations of dioptric power in general including powers with nonorthogonal and complex principal meridians.

The principal meridians of the powers of thick astigmatic systems, like the eye, are not necessarily at right angles. The consequence is a class of phenomena included in the category commonly described as irregular astigmatism. The conventional principal meridional representation of power, however, is unsuited to quantitative analysis. This paper presents equations for converting from the principal meridional form of power to a representation, the dioptric power matrix, which is amenable to quantitative analysis. It generalizes an earlier paper which treated only powers of a conventional form in which the principal meridians are always at right angles. It copes in particular with what are known as asymmetric powers. A routine is also presented for converting in the reverse direction, from the power matrix to the principal meridional form of power. The principal meridional form of power turns out not always to be unique, there being distinct powers (they are asymmetric) with the same principal powers and meridians. Thus, in general, the dioptric power matrix is a satisfactory representation of power while the principal meridional representation is not.

Data Interpretation, Statistical↗

Meridians in acupuncture and infrared imaging.

The meridians in acupuncture are hypothesized to be made up of polarized molecules. Quantum excitations, quasi-particles and others are assumed to be the media of communication between different parts of the body connected by meridians. Infrared pictures are taken to depict the effect of acupuncture on one acupoint of a meridian to a far away pain area.

Acupuncture↗

The effect of text orientation, visual meridian, and inter-character spacing on word identification in the retinal periphery.

Previous research has demonstrated that the masking effects of flankers about a target in the peripheral retina are not isotropic. Rather, regions of lateral interaction are ellipsoid in shape with the major axis oriented radially along a meridian through the fovea. This finding leads to the counterintuitive prediction that horizontal text positioned to the right of fixation might be read more slowly than similarly positioned text oriented diagonally or vertically. Similarly, vertically oriented text above fixation might be read more slowly than horizontally or diagonally oriented text above fixation. We investigated the effect of text orientation and inter-character spacing on word identification in the retinal periphery. Text was presented by rapid serial visual presentation. Words were centered 3 degrees from fixation along four visual field meridians (VM) (right horizontal, upper-right diagonal, vertical, and upper-left diagonal). Regardless of VM identification, performance was best for horizontal text, declining slightly for orientations between +60 degrees and -60 degrees and declining more quickly for acute orientations. A weak effect of VM was observed for text with normal inter-character spacing. Performance was best for text centered along the horizontal meridian and declined slightly along the other VM. Finally, identification rates increased by approximately 33 words min(-1) with the addition of one character space between adjacent letters. The word-recognition processes are very tolerant of text orientation, exhibiting a modest decline for orientations within +/- 60 of horizontal regardless of VM.

Adult↗

The head-centered meridian effect: auditory attention orienting in conditions of impaired visuo-spatial information.

This paper examines the characteristics of spatial attention orienting in situations of visual impairment. Two groups of subjects, respectively schizophrenic and blind, with different degrees of visual spatial information impairment, were tested. In Experiment 1, the schizophrenic subjects were instructed to detect an auditory target, which was preceded by a visual cue. The cue could appear in the same location as the target, separated from it respectively by the vertical visual meridian (VM), the vertical head-centered meridian (HCM) or another meridian. Similarly to normal subjects tested with the same paradigm (Ferlazzo, Couyoumdjian, Padovani, and Olivetti Belardinelli, 2002), schizophrenic subjects showed slower reactions times (RTs) when cued, and when the target locations were on the opposite sides of the HCM. This HCM effect strengthens the assumption that different auditory and visual spatial maps underlie the representation of attention orienting mechanisms. In Experiment 2, blind subjects were asked to detect an auditory target, which had been preceded by an auditory cue, while staring at an imaginary point. The point was located either to the left or to the right, in order to control for ocular movements and maintain the dissociation between the HCM and the VM. Differences between crossing and no-crossing conditions of HCM were not found. Therefore it is possible to consider the HCM effect as a consequence of the interaction between visual and auditory modalities. Related theoretical issues are also discussed.

Adolescent↗

Multimeridional refraction: dependence of the measurement accuracy on the number of meridians refracted.

A Monte Carlo simulation of multimeridional refraction measurements was used to investigate the dependence of the accuracy of the measurement on the number of meridians refracted, N, and on the standard deviation of a measurement in a single meridian, sigma. For the description of the measurement errors, the residual refraction values were used, i.e., the parameters of the refraction remaining after application of the measured correction. The distributions of the residual refraction values were found to be independent of the "true" refraction values; in addition, by means of a factor square root of N/sigma, reduced residual refraction values could be defined which also were independent of N and sigma. A vector space proposed by Lakshminarayanan and Varadharajan (based on Long's power matrix) was used to represent the joint distribution of the residual refraction values in three-dimensional space. It was found to be a three-variate Gaussian distribution with zero mean and diagonal covariance matrix. It could further be shown that the vector space proposed by Harris is identical to the one used, up to a linear transformation. Several criteria, based on the one- and three-dimensional distributions and corresponding to different levels of accuracy, are discussed resulting in a wide range of answers about the number of meridians to be refracted.

Analysis of Variance↗

The representation of the horizontal meridian in the primary visual cortex.

The authors report the findings of two patients that confirm the location of the horizontal meridian in the human visual cortex. The first patient had an inferior quadrant defect with a band of horizontal meridian sparing. Magnetic resonance imaging showed a lesion concentrated along the medial striate cortex. The second patient had a homonymous horizontal defect that resulted from removal of an arteriovenous malformation located in the lateral striate cortex. The findings of these two patients demonstrate that the horizontal meridian is represented at the calcarine fissure base in the primary visual cortex.

Adult↗

Visual spatial attention to stimuli presented on the vertical and horizontal meridian: an ERP study.

In the first experiment, 48 subjects carried out a visual spatial attention task. Stimuli were presented at the vertical meridian, either above or below a fixation dot, and the subjects were instructed to attend to one of these stimulus positions and ignore the other position. In three different conditions, the distances between stimulus positions and fixation were 0.5 degrees, 0.9 degrees, and 1.3 degrees. Subjects searched for the presence of prememorized target letters at the attended location: memory load was one or four items in different conditions. The P1/N1 enhancement typically found on the horizontal dimension was not observed on the vertical dimension. Instead, a positive shift of the attended compared with the unattended stimuli was found, which was most prominent at anterior electrodes. This positivity showed effects of the distance manipulation. The N2b-P3a effects of attention and the effect of memory load (search negativity) normally present in this kind of selective search task were also found. Reaction times were faster when attention was directed above fixation than when it was directed below fixation. The event-related potential data suggested that this difference could be attributed to a more efficient neglecting of irrelevant stimuli presented below fixation. In Experiment 2, we examined whether the absence of the P1/N1 enhancement as the result of spatial attention in Experiment 1 could be attributed to (a) the presentation of stimuli along the vertical meridian instead of along the horizontal meridian, (b) the use of midline electrodes instead of lateralized electrodes, and (c) the relatively small spatial separation between the relevant and irrelevant stimuli. Twelve subjects searched for the presence of a single target letter at an attended position in three different conditions. In two of the conditions the letters were presented to the left or right of fixation. The distance between fixation and the stimulus positions was 1.3 degrees in one of these conditions and 3 degrees in the other condition. In the third condition, the stimuli were presented at 3 degrees above or below fixation. In all three conditions effects similar to those in Experiment 1 were observed. In addition, in all three conditions an enhancement of the P1 and N1 components was found at two lateral occipitotemporal electrodes.

Adolescent↗