An Overview of Medical Research on Magnetism
Magnetism's checkered history of fraud and hype tends to make medical researchers a bit hesitant to commit time and money to magnets. In addition, the research published on permanent magnets has often been negative. This is in stark contrast to individual reports of the benefit of wearing a magnet. And this is where you have to distinguish between so called "anecdotal evidence" and expensive university studies. Most medical problems that are left untreated will resolve naturally. It is evolution's gift to us. So if you rub on snake oil, you will probably get better and may be tempted to brag about your recovery. In addition, if you think you are going to get better, you have the power of positive thinking on your side. All of these considerations make personal endorsements subject to caution. It doesn't mean they are wrong. It just means you have to be careful how you interpret them. Good medical research, on the other hand, is conducted with control groups and double blind procedures to eliminate such problems. If medical research doesn't back up anecdotal evidence, it may mean that a placebo effect is at work.
The medical research on permanent magnets is somewhat contradictory, some showing improvement and some showing little or no benefit. For instance, a Baylor College study of post polio patients showed significant benefit. While, a University of Virginia study of fibromyalgia patients showed only a slight benefit. And many others report absolutely no gains. Electromagnetic research seems to be more definitive and may be divided into 3 categories: environmental, transcranial and low level PEMF. Environmental studies are concerned with the possible hazards posed by power lines, computer monitors and cell phones. Transcranial refers to very high power pulses ( 1 tesla and higher ) used to probe the workings of the brain and other nerve tissue. PEMF stands for Pulsed ElectroMagnetic Field and low level PEMF concerns the types of magnetic fields used in alternative medicine. The table below presents a list of interesting, published medical research on low level PEMF plus the two most referenced studies of permanent magnets. If you click on abstract, you will jump to a paragraph describing the research. Clicking "Return to Table" at the end of each abstract will return you to the list.
Description of Magnetic Research
|Polio Pain||A. Study of permanent magnets and post-polio pain||300-500 Gauss|
|Fibromyalgia||B. Study of permanent magnets to treat fibromyalgia||Not stated|
|Nitric Oxide||1. Nitric oxide synthase and PEMF in rat brains||1 Gauss|
|Ligaments||2. Effects of PEMF on ligaments in rabbits||50 Gauss|
|Cell Walls||3. Relaxation of lipid-bilayers exposed to PEMF||100 Gauss|
|Neurons||4. Neurite growth using PEMF and NGF in chicks||40 Gauss|
|Membranes||5. Permeability of rat cell membranes under PEMF||60-240 Gauss|
|Endocrine||6. Reaction of rat endocrine system to PEMF||200 Gauss|
|Skin Wound||7. Effects of PEMF on healing of rat skin wounds||80 Gauss|
|Circulation||8. Microcirculatory enhancement with PEMF in rats||Not stated|
|Arthritis||9. Effects of PEMF on human osteoarthritis||Not stated|
|Diabetes||10. Effects of PEMF on diabetic polyneuropathy||Not stated|
|Pain||11. Using PEMF for neuropathic pain in humans||20 G at 30 Hz|
|Glaucoma||12. The influence of PEMF on open-angle glaucoma||80 G at 2 G/ms|
|Bipolar||13. Using PEMF to treat human bipolar depression||0-10 Gradient|
A. Study of static magnets to treat post-polio pain
Title: Response of pain to static magnetic fields in postpolio patients: a double-blind pilot study
Vallbona C, Hazlewood CF, Jurida G.
Department of Family and Community Medicine
Baylor College of Medicine, Houston, TX
OBJECTIVE: To determine if the chronic pain frequently presented by postpolio patients can be relieved by application of magnetic fields applied directly over an identified pain trigger point. DESIGN: Double-blind randomized clinical trial. SETTING: The postpolio clinic of a large rehabilitation hospital. PATIENTS: Fifty patients with diagnosed postpolio syndrome who reported muscular or arthritic-like pain. INTERVENTION: Application of active or placebo 300 to 500 Gauss magnetic devices to the affected area for 45 minutes. MAIN OUTCOME MEASURE: Score on the McGill Pain Questionnaire. RESULTS: Patients who received the active device experienced an average pain score decrease of 4.4 +/- 3.1 (p < .0001) on a 10-point scale. Those with the placebo devices experienced a decrease of 1.1 +/- 1.6 points (p < .005). The proportion of patients in the active-device group who reported a pain score decrease greater than the average placebo effect was 76%, compared with 19% in the placebo-device group (p < .0001). CONCLUSIONS: The application of a device delivering static magnetic fields of 300 to 500 Gauss over a pain trigger point results in significant and prompt relief of pain in postpolio subjects. [Return to Table]
Arch Phys Med Rehabil. 1997 Nov;78(11):1200-3
B. Study of static magnets to treat fibromyalgia patients
Title: Static Magnetic Fields for Treatment of Fibromyalgia: A Randomized Controlled Trial
Alan P. Alfano, MD, Physical Medicine and Rehabilitation, University
Ann Gill Taylor, MS, EdD, RN, FAAN, Center of Complementary Therapies University of Virginia
Pamela A. Foresman, BA, Center of Complementary and Alternative Therapies University of Virginia
Philomena R. Dunkl, PhD, Center of Complementary and Alternative Therapies University of Virginia
Geneviève G. McConnell, PhD-C, DO, Physical Medicine, University of Virginia Health System
Mark R. Conaway, PhD, Department of Health Evaluation Sciences, University of Virginia
George T. Gillies, PhD, Department of Mechanical and Aerospace Engineering, University of Virginia
Objective: To test effectiveness of static magnetic fields of two different configurations, produced by magnetic sleep pads, as adjunctive therapies in decreasing patient pain perception and improving functional status in individuals with fibromyalgia.
Design: Randomized, placebo-controlled, 6-month trial conducted from November 1997 through December 1998.
Setting and subjects: Adults who met the 1990 American College of Rheumatology criteria for fibromyalgia were recruited through clinical referral and media announcements and evaluated at a university-based clinic.
Interventions: Subjects in Functional Pad A group used a pad for 6 months that provided whole-body exposure to a low, uniform static magnetic field of negative polarity. Subjects in the Functional Pad B group used a pad for 6 months that exposed them to a low static magnetic field that varied spatially and in polarity. Subjects in two Sham groups used pads that were identical in appearance and texture to the functional pads but contained inactive magnets; these groups were combined for analysis. Subjects in the Usual Care group continued with their established treatment regimens.
Outcome measures: Primary outcomes were the change scores at 6 months in the following measures: functional status (Fibromyalgia Impact Questionnaire), pain intensity ratings, tender point count, and a tender point pain intensity score.
Results: There was a significant difference among groups in pain intensity ratings (p = 0.03), with Functional Pad A group showing the greatest reduction from baseline at 6 months. All four groups showed a decline in number of tender points, but differences among the groups were not significant (p = 0.72). The functional pad groups showed the largest decline in total tender point pain intensity, but overall differences were not significant (p = 0.25). Improvement in functional status was greatest in the functional pad groups, but differences among groups were not significant (p = 0.23).
Conclusions: Although the functional pad groups showed improvements in functional status, pain intensity level, tender point count, and tender point intensity after 6 months of treatment, with the exception of pain intensity level these improvements did not differ significantly from changes in the Sham group or in the Usual Care group. [Return to Table]
Journal of Alternative and Complementary Medicine. Feb 2001, Vol. 7, No. 1, Pages 53-64
1. Nitric oxide synthase enhancement using PEMF in rat brains
Title: Pulsed magnetic fields enhance nitric oxide synthase activity in rat cerebellum
Noda Y, Mori A, Liburdy RP, Packer L.
Department of Molecular and Cell Biology
University of California at Berkeley
The effect of pulsed magnetic fields on nitric oxide synthase (NOS) activity in the rat brain was investigated. Sprague-Dawley rats (male, 200-250 g body weight) brain were dissected regionally, and the crude enzyme solutions were treated with pulsed DC, AC or static DC magnetic fields at 0 degrees C for 1 h. After exposure, NOS activity was measured as nitrite and nitrate levels generated from incubation with arginine, CaCl(2) and beta-nicotinamide adenine dinucleotide phosphate. Under these experimental conditions, neither AC nor static DC field treatment showed any significant change in NOS activity. A significant increase in NOS activity was observed in the cerebellum (111.2+/-2.0%, P<0.05, five separate experiments) for a 1 Gauss (0.1 mT) pulsed DC field. Under the same experimental condition, only a slight change or no effect was observed in the hippocampus, cortex, medulla oblongata, hypothalamus, striatum and midbrain. These studies suggest that pulsed magnetic fields result in a different effect on NOS activity in the cerebellum of the rats. [Return to Table]
Pathophysiology. 2000 Jul;7(2):127-130
2. Effects of PEMF on the healing of ligaments in rabbits
Title: Effects of pulsing electromagnetic fields on the ligament healing in rabbits
Lin Y, Nishimura R, Nozaki K, Sasaki N, Kadosawa T, Goto N, Date M,
Department of Veterinary Surgery, University of Tokyo, Japan.
Effects of pulsing electromagnetic fields (PEMFs) on ligament healing were investigated using 80 rabbits. All animals received square resection (4 mm x 4 mm) of both patellar ligaments in full thickness at their center. They were divided into 4 groups of 20 rabbits each and stimulated with different electromagnetic intensity of 0 (control), 2, 10, and 50 gauss (G) for 6 hr daily. Pulse frequency and pulse width were 10 Hz and 25 microseconds, respectively. After PEMFs stimulations for 1, 2, 3 and 4 weeks, 5 animals of each group were euthanized and the regenerated tissue at the defective portion was investigated histologically and biomechanically. Histologically, the tissue stimulated by PEMFs showed an earlier increase in capillaries and fibroblasts and more matured, prominent longitudinal orientation of collagen fibers than those of control groups. Among the rabbits stimulated electromagnetically, those stimulated at 50 G revealed the earliest ligament healing. Tensile strength of regenerated ligament tissues of any PEMFs groups increased significantly at 1 and 2 weeks after operation, however, at 3 and 4 weeks after operation, there were no significant differences between groups. Among these values, those of 50 G group were the highest consistently during most of the experimental period. From the above results, PEMFs enhanced the earlier stage of ligament healings and 50 G gauss seemed to be the most effective among the 3 field intensities used. This promoting effect may potentiate earlier recovery after the ligament injury. [Return to Table]
J Vet Med Sci. 1992 Oct;54(5):1017-22
3. Electric relaxation of lipid-bilayer structures exposed to PEMF
Title: Electric relaxation processes in lipid-bilayers after exposure to weak magnetic pulses
Botanisches Institut der Universitat Munchen, Germany
Biological effects of weak magnetic fields are widespread, but poorly understood. Besides magnetic particles, which have been shown to be involved in only few cases, membranes are discussed as the site of perception. However, the mechanism is unknown. We have subjected pure lipid membranes to weak magnetic pulses, and found, that their electric properties are modified. Black lipid membranes were prepared from purified asolectin on a teflon septum separating electrically the two chambers of a teflon cuvette, using the technique of Mueller et al. (1962). Single magnetic pulses were applied for 10 micros, whose intensity could be varied from 0 to 100 G (0 to 10 mT) at the membrane. Directly after the pulse decay, the conductance of the bilayers was scanned with 10 periods of a 1 kHz triangle alternating voltage (eg. a measurement time window of 10 ms). Frequency spectra of the bilayer current rose by a frequency dependent factor < or = 2 in a broad region around 80 kHz, when the amplitude of the preceding magnetic pulse was increased from 0 to 100 G. The data show, that weak magnetic fields can significantly change the electrical conductance of lipid films. The relaxation of electrons in a two-dimensional quantum state will be discussed as a possible origin of these effects. [Return to Table]
Z Naturforsch [C]. 2001 Sep-Oct;56(9-10):831-7
4. Neurite growth enhancement using PEMF and NGF in chicks
Title: Effects of pulsed magnetic fields on neurite outgrowth from chick embryo dorsal root ganglia
Greenebaum B, Sutton CH, Vadula MS, Battocletti JH, Swiontek T,
J, Sisken BF.
Biomedical Research Institute, University of Wisconsin-Parkside
We have previously shown that neurite outgrowth from 6-day chick embryo dorsal root ganglia (DRG) in vitro was stimulated when nerve growth factor (NGF) and pulsed magnetic fields (PMF) are used in combination. 392 DRGs were studied in a field excited by a commercial PMF generator. We have now analyzed an additional 416 DRGs exposed to very similar PMF's produced by an arbitrary wavefrom generator and power amplifier. We reproduced our previous findings that combination of NGF and bursts of asymmetric, 220 microsecond-wide, 4.0 mT-peak pulses induced significantly (p < 0.05) greater outgrowth than NGF alone, that fields without NGF do not significantly alter outgrowth, and that, unlike NGF alone, 4.0 mT fields and NGF can induce asymmetric outgrowth. The asymmetry does not seem to have a preferred orientation with respect to the induced electric field. Analysis of the data for the entire 808 DRGs confirms these findings. Importantly, we find similar results for pulse bursts repeated at 15 or 25 Hz. [Return to Table]
5. Permeability of rat cell membranes exposed to PEMF
Title: The permeability of rat erythrocyte membranes for sodium and potassium ions during exposure to pulsed electromagnetic field under head-down-tilt hypokinesia [Article in Russian]
Loginov VA, Timonin IM, Minchenko BI, Klimovitskii VIa.
The effect of a low-frequency (1 and 10 Hz) pulse electromagnetic field (PEMF) on permeability of erythrocyte membrane in 47 rats while being exposed to a 14-day head-down tilt (HDT) and in 60 control rats was studied. After exposure to PEMF (20 min, 6-24 mT) the rats were Na(+)-, K(+)-cotransport and Na+,Na(+)-metabolism, Na and K losses as well as specific activity of Na(+)-, K(+)-ATP in the erythrocytes have been measured. An ability of PEMF to inhibit an ATP activity by 20-30% and to increase the rate of ions loss from the cells has been revealed. Under HDT, these effects are preserved. The possible mechanisms of PEMF effect on an ionic permeability are discussed. [Return to Table]
Aviakosm Ekolog Med. 1992 Sep-Dec;26(5-6):71-5
6. Reaction of rat endocrine system to PEMF
Title: Reaction of the endocrine system and peripheral blood of rats to a single and chronic exposure to pulsed low-frequency electromagnetic field [Article in Russian]
Zagorskaia EA, Rodina GP.
Wistar male rats underwent a single exposure for 20 min, 1 and 2.5 hour to a pulsed electromagnetic field of 20 mT or a single exposure for 2.5 hour and a chronic exposure for 6 hours a day during 30 days to a pulsed electromagnetic field of 0.1 mT, the pulse time and an interval between pulses being 10(-2) sec. As a result, the experimental animals showed changes in the activity of the adrenals, thyroid and sex glands as well as eosinopenia and lymphopenia. The concentration of thyroid hormones and lymphocytes remained lowered during 2 months after a single exposure to 20 mT. In some cases the exposure modified the physiological responses of rats to an acute stress-5-hour immobilization. [Return to Table]
Kosm Biol Aviakosm Med. 1990 Mar-Apr;24(2):56-60
7. Effects of PEMF on the healing of rat skin wounds
Title: Effects of pulsed extremely-low-frequency magnetic fields on skin wounds in the rat
Ottani V, De Pasquale V, Govoni P, Franchi M, Zaniol P, Ruggeri A.
Istituto di Anatomia Umana Normale, Bologna, Italy.
Rats with skin-wounds surgically created on their backs were exposed immediately after surgery and every 12 h thereafter to pulsed, extremely-low-frequency magnetic fields. The shape of the pulse was a positive triangle (50 Hz, 8 mT peak). The rate of healing of skin wounds was evaluated macroscopically and by light and electron microscopy at 6, 12, 21, and 42 days after the operation. A significant increase in the rate of wound contraction was found in rats treated with magnetic fields. Forty-two days after surgery all treated animals show fully closed wounds, while control rats at the same time intervals still lacked a final 6% of the wound surface to be covered. Treated rats showed earlier cellular organization, collagen formation and maturation, and a very early appearance of newly formed vascular network. [Return to Table]
8. Microcirculatory enhancement using PEMF in rats
Title: Microcirculatory effects of pulsed electromagnetic fields
Smith TL, Wong-Gibbons D, Maultsby J.
Department of Orthopaedic Surgery
Wake Forest University School of Medicine
PURPOSE: Pulsed electromagnetic fields (PEMF) are used clinically to expedite healing of fracture non-unions, however, the mechanism of action by which PEMF stimulation is effective is unknown. The current study examined the acute effects of PEMF stimulation on arteriolar microvessel diameters in the rat cremaster muscle. The study hypothesis was that PEMF would increase arteriolar diameters, a potential mechanism involved in the healing process. METHODS: Local PEMF stimulation/sham stimulation of 2 or 60 min duration was delivered to the cremaster muscle of anesthetized rats. Arteriolar diameters were measured before and after stimulation/sham stimulation using intravital microscopy. Systemic hemodynamics also were monitored during PEMF stimulation. RESULTS: Local PEMF stimulation produced significant (p<0.001) vasodilation, compared to pre-stimulation values, in cremasteric arterioles in anesthetized rats (n=24). This dilation occurred after 2 min of stimulation (9% diameter increase) and after 1 h of stimulation (8.7% diameter increase). Rats receiving "sham" stimulation (n=15) demonstrated no statistically significant change in arteriolar diameter following either "sham" stimulation period. PEMF stimulation of the cremaster (n=4 rats) did not affect systemic arterial pressure or heart rate, nor was it associated with a change in tissue environmental temperature. CONCLUSIONS: These results support the hypothesis that local application of a specific PEMF waveform can elicit significant arteriolar vasodilation. Systemic hemodynamics and environmental temperature could not account for the observed microvascular responses. [Return to Table]
J Orthop Res. 2004 Jan;22(1):80-4
9. Effects of PEMF on human osteoarthritis of the knee and spine
Title: The effect of pulsed electromagnetic fields in the treatment of osteoarthritis of the knee and cervical spine
Trock DH, Bollet AJ, Markoll R.
Department of Medicine, Danbury Hospital, CT.
OBJECTIVE. We conducted a randomized, double blind clinical trial to determine the effectiveness of pulsed electromagnetic fields (PEMF) in the treatment of osteoarthritis (OA) of the knee and cervical spine. METHODS. A controlled trial of 18 half-hour active or placebo treatments was conducted in 86 patients with OA of the knee and 81 patients with OA of the cervical spine, in which pain was evaluated using a 10 cm visual analog scale, activities of daily living using a series of questions (answered by the patient as never, sometimes, most of the time, or always), pain on passive motion (recorded as none, slight, moderate, or severe), and joint tenderness (recorded using a modified Ritchie scale). Global evaluations of improvement were made by the patient and examining physician. Evaluations were made at baseline, midway, end of treatment, and one month after completion of treatment. RESULTS. Matched pair t tests showed extremely significant changes from baseline for the treated patients in both knee and cervical spine studies at the end of treatment and the one month followup observations, whereas the changes in the placebo patients showed lesser degrees of significance at the end of treatment, and had lost significance for most variables at the one month followup. Means of the treated group of patients with OA of the knee showed greater improvement from baseline values than the placebo group by the end of treatment and at the one month followup observation. Using the 2-tailed t test, at the end of treatment the differences in the means of the 2 groups reached statistical significance for pain, pain on motion, and both the patient overall assessment and the physician global assessment. The means of the treated patients with OA of the cervical spine showed greater improvement from baseline than the placebo group for most variables at the end of treatment and one month followup observations; these differences reached statistical significance at one or more observation points for pain, pain on motion, and tenderness. CONCLUSION. PEMF has therapeutic benefit in painful OA of the knee or cervical spine. [Return to Table]
J Rheumatol. 1994 Oct;21(10):1903-11
10. Effects of PEMF on patients with diabetic polyneuropathy
Title: The use of pulsed electromagnetic fields with complex modulation in the treatment of patients with diabetic polyneuropathy
Musaev AV, Guseinova SG, Imamverdieva SS.
Science Research Institute of Medical Rehabilitation, Baku, Azerbaidzhan.
Clinical and electroneuromyographic studies were performed in 121 patients with diabetic polyneuropathy (DPN) before and after courses of treatment with pulsed electromagnetic fields with complex modulation (PEMF-CM) at different frequencies (100 and 10 Hz). Testing of patients using the TSS and NIS LL scales demonstrated a correlation between the severity and frequency of the main subjective and objective effects of disease and the stage of DPN. The severity of changes in the segmental-peripheral neuromotor apparatus--decreases in muscle bioelectrical activity, the impulse conduction rate along efferent fibers of peripheral nerves, and the amplitude of the maximum M response--depended on the stage of DPN and the duration of diabetes mellitus. The earliest and most significant electroneuromyographic signs of DPN were found to be decreases in the amplitude of the H reflex and the Hmax/Mmax ratio in the muscles of the lower leg. Application of PEMF-CM facilitated regression of the main clinical symptoms of DPN, improved the conductive function of peripheral nerves, improved the state of la afferents, and improved the reflex excitability of functionally diverse motoneurons in the spinal cord. PEMF-CM at 10 Hz was found to have therapeutic efficacy, especially in the initial stages of DPN and in patients with diabetes mellitus for up to 10 years. [Return to Table]
Neurosci Behav Physiol. 2003 Oct;33(8):745-52
11. Using PEMF to control refractory neuropathic pain in humans
Title: Pulsed magnetic field therapy in refractory neuropathic pain secondary to peripheral neuropathy: electrodiagnostic parameters--pilot study
Weintraub MI, Cole SP.
New York Medical College
CONTEXT: Neuropathic pain (NP) from peripheral neuropathy (PN) arises from ectopic firing of unmyelinated C-fibers with accumulation of sodium and calcium channels. Because pulsed electromagnetic fields (PEMF) safely induce extremely low frequency (ELF) quasirectangular currents that can depolarize, repolarize, and hyperpolarize neurons, it was hypothesized that directing this energy into the sole of one foot could potentially modulate neuropathic pain. OBJECTIVE: To determine if 9 consecutive 1-h treatments in physician's office (excluding weekends) of a pulsed signal therapy can reduce NP scores in refractory feet with PN. DESIGN/SETTING/PATIENTS: 24 consecutive patients with refractory and symptomatic PN from diabetes, chronic inflammatory demyelinating polyneuropathy (CIDP), pernicious anemia, mercury poisoning, paraneoplastic syndrome, tarsal tunnel, and idiopathic sensory neuropathy were enrolled in this nonplacebo pilot study. The most symptomatic foot received therapy. Primary endpoints were comparison of VAS scores at the end of 9 days and the end of 30 days follow-up compared to baseline pain scores. Additionally, Patients' Global Impression of Change (PGIC) questionnaire was tabulated describing response to treatment. Subgroup analysis of nerve conduction scores, quantified sensory testing (QST), and serial examination changes were also tabulated. Subgroup classification of pain (Serlin) was utilized to determine if there were disproportionate responses. INTERVENTION: Noninvasive pulsed signal therapy generates a unidirectional quasirectangular waveform with strength about 20 gauss and a frequency about 30 Hz into the soles of the feet for 9 consecutive 1-h treatments (excluding weekends). The most symptomatic foot of each patient was treated. RESULTS: All 24 feet completed 9 days of treatment. 15/24 completed follow-up (62%) with mean pain scores decreasing 21% from baseline to end of treatment (P=0.19) but with 49% reduction of pain scores from baseline to end of follow-up (P<0.01). Of this group, self-reported PGIC was improved 67% (n=10) and no change was 33% (n=5). An intent-to-treat analysis based on all 24 feet demonstrated a 19% reduction in pain scores from baseline to end of treatment (P=0.10) and a 37% decrease from baseline to end of follow-up (P<0.01). Subgroup analysis revealed 5 patients with mild pain with nonsignificant reduction at end of follow-up. Of the 19 feet with moderate to severe pain, there was a 28% reduction from baseline to end of treatment (P<0.05) and a 39% decrease from baseline to end of follow-up (P<0.01). Benefit was better in those patients with axonal changes and advanced CPT baseline scores. The clinical examination did not change. There were no adverse events or safety issues. CONCLUSIONS: These pilot data demonstrate that directing PEMF to refractory feet can provide unexpected shortterm analgesic effects in more than 50% of individuals. The role of placebo is not known and was not tested. The precise mechanism is unclear yet suggests that severe and advanced cases are more magnetically sensitive. Future studies are needed with randomized placebo-controlled design and longer treatment periods. [Return to Table]
Neurorehabil Neural Repair. 2004 Mar;18(1):42-6
12. The influence of PEMF on human open-angle glaucoma
Title: The effect of a pulsed electromagnetic field on ocular hydrodynamics in open-angle glaucoma
Tsisel'skii IuV [Article in Russian]
The influence of pulse electromagnetic field on the hydrodynamics of the eye in open-angle glaucoma has been studied using the method and the device suggested at the Filatov Institute. The characteristics of the action were: impulse frequency--50 Hz, duration--0.02 sec., pulse form--rectangular, rate of pulse rise--4/10(-4) sec., rate of magnetic induction rise--2/10(-4) mT/sec., amplitude value of magnetic induction at the pulse level--8.0-8.5 mT, duration of the procedure--7 min. Ten session in a total. Observations over 150 patients (283 eyes) with latent, initial and advanced glaucoma have shown that the usage of pulse electromagnetic field exerts influence on the hydrodynamics of the eye in open-angle glaucoma; stimulates the rise of aqueous outflow and production, the reduction of the Becker's coefficient. At the latent stage of the disease, normalization of outflow was recorded in 25% of cases, at the initial and advanced stages--in 17.8% and 16.0% of cases, respectively. The investigations carried out allow to recommend the mentioned method for a complex treatment of open-angle glaucoma. [Return to Table]
Oftalmol Zh. 1990;(2):89-92
13. Using PEMF to treat bipolar depression in human patients
Title: Low-field magnetic stimulation in bipolar depression using an MRI-based stimulator
Rohan M, Parow A, Stoll AL, Demopulos C, Friedman S, Dager S, Hennen
BM, Renshaw PF.
Brain Imaging Center at McLean Hospital, Belmont, MA
OBJECTIVE: Anecdotal reports have suggested mood improvement in patients with bipolar disorder immediately after they underwent an echo-planar magnetic resonance spectroscopic imaging (EP-MRSI) procedure that can be performed within clinical MR system limits. This study evaluated possible mood improvement associated with this procedure. METHOD: The mood states of subjects in an ongoing EP-MRSI study of bipolar disorder were assessed by using the Brief Affect Scale, a structured mood rating scale, immediately before and after an EP-MRSI session. Sham EP-MRSI was administered to a comparison group of subjects with bipolar disorder, and actual EP-MRSI was administered to a comparison group of healthy subjects. The characteristics of the electric fields generated by the EP-MRSI scan were analyzed. RESULTS: Mood improvement was reported by 23 of 30 bipolar disorder subjects who received the actual EP-MRSI examination, by three of 10 bipolar disorder subjects who received sham EP-MRSI, and by four of 14 healthy comparison subjects who received actual EP-MRSI. Significant differences in mood improvement were found between the bipolar disorder subjects who received actual EP-MRSI and those who received sham EP-MRSI, and, among subjects who received actual EP-MRSI, between the healthy subjects and the bipolar disorder subjects and to a lesser extent between the unmedicated bipolar disorder subjects and the bipolar disorder subjects who were taking medication. The electric fields generated by the EP-MRSI scan were smaller (0.7 V/m) than fields used in repetitive transcranial magnetic stimulation (rTMS) treatment of depression (1-500 V/m) and also extended uniformly throughout the head, unlike the highly nonuniform fields used in rTMS. The EP-MRSI waveform, a 1-kHz train of monophasic trapezoidal gradient pulses, differed from that used in rTMS. CONCLUSIONS: These preliminary data suggest that the EP-MRSI scan induces electric fields that are associated with reported mood improvement in subjects with bipolar disorder. The findings are similar to those for rTMS depression treatments, although the waveform used in EP-MRSI differs from that used in rTMS. Further investigation of the mechanism of EP-MRSI is warranted. [Return to Table]
Am J Psychiatry. 2004 Jan;161(1):93-8