Blog Arasys Perfector - Xanya Sofra Weiss

INTRODUCTION

As aggressive therapy with combination surgery, chemotherapy, and radiotherapy (RT) increases tumor control in head-and-neck neoplasms, posttreatment quality-of-life issues remain problematic (1). One area of concern is progressive fibrosis of soft tissue in the head, neck, and supraclavicular area. For many patients, palpation of the treated areas reveals hard, unyielding tissue that limits range of motion and/or leads to pain associated with movement. The concept of investigating microcurrent therapy to treat radiation-induced fibrosis arose from the observation of a salivary gland patient who was receiving microcurrent therapy for the surgical scar at a family physician’s office while receiving neutron therapy at Fermilab. The patient experienced significantly milder erythema and mucositis than would historically be expected for radical RT in the neck area. This serendipitous observation led to a hypothesis that microcurrent therapy could be beneficial in managing the effects of RT.

METHODS AND MATERIALS

Twenty-six head-and-neck cancer patients who had completed RT and were experiencing tissue discomfort or limitations caused by fibrosis participated in the study. Because this was a pilot study to determine the efficacy of a new use of a standard therapeutic technique, it was important that all participants have quantifiable symptoms with no expectation of resolution without intervention. Hence, patients experiencing documented progressive fibrosis were targeted. The staff made objective range-of-motion measurements, and subjective complaints were solicited from the patients. The procedure and its possible lack of benefit were explained to the patients before they signed a document indicating informed consent. The Provena Saint Joseph Hospital Institutional Review Board approved the protocol. Selection of study subjects Eligible patients had finished either photon or neutron therapy at least 6 months before entering the study and had no evidence of disease. They had mental alertness sufficient to understand, evaluate, and consent to the protocol, which included the availability for b.i.d. treatments daily for 1 week and the ability to return for scheduled follow-up visits. Exclusion criteria included the use of a pacemaker, use of calcium-channel blocker drugs, pregnancy, and a life expectancy of 6 months. Individuals who were unable to abstain from physical therapy to the affected area, routine use of antiinflammatory steroids, or nonsteroidal antiinflammatory drugs during the treatment and follow-up period were also excluded. Table 1 summarizes the baseline characteristics of the participants. Choice of microcurrent technique and schedule The use of electrical stimulation for pain relief is well established in physical therapy centers. Many commercial electrical stimulation devices are available, most of which are commonly referred to as transcutaneous electrical nerve stimulation units. Typical units emit electrical pulses with alternating positive and negative polarities in the 10–500- kHz range and currents in the milliampere range. Microcurrent units are often incorrectly referred to as transcutaneous electrical nerve stimulation units, but microcurrent units deliver lower currents (microampere range) and lower frequencies (0.5 to several hundred hertz). In general, units using higher current and frequencies are more effective at blocking acute pain, but the pain relief is not lasting. Microcurrent therapy using lower frequencies requires longer treatment times to achieve pain relief, but the relief can endure for many hours after the treatment has terminated (5). Because the patients targeted for this study were experiencing chronic rather than acute symptoms, a microcurrent device was selected. The costs of microcurrent devices range from several hundred to thousands of dollars. Some fraction of the cost is related to packaging, but most of it is associated with the degree of sophistication of the electronic circuits. It is well known that the body’s impedance changes when electrical current passes through it. The more sophisticated devices contain circuitry that monitors impedance and adjusts the output current to compensate for changes. These devices also deliver fast rise time pulses that can affect voltagesensitive sodium and calcium ion channels (6). The Electro- Myopulse and Electro-Acuscope instruments (Biomedical Design Instruments, Burbank, CA) chosen for this study deliver impedance-controlled, fast rise time pulses. Their retail price is about $8500 each. Electrotherapy treatments are reimbursable under established billing codes. Typical charges to a patient are $40–50 per 15-min treatment. However, patients in this study were not charged for the therapy. Physical therapists use microcurrent therapy in a variety of ways, often in combination with massage, heat, and physical manipulation. Treatment schedules are not standardized, but are driven by insurance payment schedules and the patients’ personal schedules. The treatment schedule for this study was established after informal discussions with a few physical therapists who had extensive experience using the Electro-Myopulse and Electro-Acuscope instruments for treating a variety of physical complaints. All agreed that noticeable improvement could be obtained most quickly if the patient were treated b.i.d. for 3 days. All agreed that lasting improvement tended to require several treatments per month for about 6 months and that some conditions could resolve completely if this long-term treatment schedule were followed, particularly if therapy started soon after the injury or symptom occurred. Given the advanced fibrosis of many of the study patients, it was decided to administer microcurrent treatments b.i.d. for 5 days and simply observe whether this therapy had any effect on severely fibrotic tissue. Any observed improvements were not expected to be lasting, because no follow-up treatments at more spread-out intervals were scheduled. Until measurable evidence of the treatment’s effectiveness was observed, it did not seem reasonable to commit resources to a longterm treatment schedule. Objective measurement techniques As shown in Fig. 1, cervical rotation, extension/flexion, and lateral flexion were measured using two large protractors mounted in perpendicular planes. An elastic band with Velcro attachments was secured to the patient’s head to permit the placement of a small laser that pointed to degree markings on circular scales used to measure range of motion in degrees. This laser was positioned relative to the points about which the patient’s head pivots during rotation, ex- Fig. 1. Patient positioned at vertex of two mutually perpendicular protractors used to measure cervical range of motion. Fig. 2. Laser affixed to the patient’s head measures left–right cervical rotation. Impedance-controlled microcurrent therapy for RT-induced fibrosis in head-and-neck cancer ● A. J. LENNOX et al. 25 tension/flexion, and lateral flexion. Stationary lasers were used to position the patient so that the movable laser was on a line that intersected the vertex of the large protractors. Figures 2 through 4 illustrate the setup for each angular measurement. Day-to-day patient positioning accuracy was 0.25 cm, which is small compared with the protractors’ 112-cm radius. This choice of scale minimized the effect of day-to-day errors in positioning the patient’s center of rotation at the vertex of the scale. For each patient, the pretreatment data were used to classify each range of motion as asymptomatic or mildly, moderately, or severely limiting. If a patient’s range was within 90% of the optimal range for a healthy young person, that patient was classified as asymptomatic for that measurement. Ranges between 70% and 90% of optimum were designated mildly limiting, and those of 50–70% were moderately limiting. Ranges 50% of optimum were considered severely limiting.

DISCUSSION

In head-and-neck cancer patients, radiation-induced fibrosis can lead to many different complaints, depending on the size and placement of the treatment fields, the total dose, and whether the patient also underwent surgery. Limitations in neck range of motion are common and are quantifiable. Because this study was looking for objectively measured changes associated with microcurrent therapy, the protocol was designed to achieve improvement in the range of motion. Measurements were made on all patients in the study regardless of whether the patient considered range-of-motion limitations to be a problem. Most of the patients in the mildly and moderately limited groups had learned to compensate for the limitations and were surprised when the measurements showed how much capability they had lost. The patients who were most severely limited received the greatest degree of benefit. Patients also received relief from a number of complaints not directly targeted in the treatment protocol, the most significant of which were trismus and xerostomia. When the study was completed, some case studies were done using a different microcurrent protocol along with physical therapy for the relief of trismus. The results were encouraging and suggest that additional studies on the role of microcurrent therapy in treating trismus are warranted. Our xerostomia data are currently being analyzed and will be published separately. Perhaps the most encouraging outcome of this study was that many of the benefits observed at the end of the treatment week were sustained. In some cases, continued improvement occurred during the 3-month follow-up period, suggesting that the treatment had initiated tissue repair. The beneficial effects of electric current for soft tissue repair have been described by Polk (8). The exact mechanisms for tissue repair are not completely understood, but one theory indicates that microcurrent stimulation influences the migration of extracellular calcium ions to penetrate the cell membrane. The higher level of intracellular calcium encourages increased synthesis of adenosine triphosphate. Protein synthesis is encouraged by affecting mechanisms that control DNA, thus encouraging cellular repair and replication (9). It is also believed that microvoltage may affect the cascade of reactions involved in a variety of inflammatory responses. Our data support the view that microcurrent therapy can initiate long-term benefit for patients with fibrosis. At the onset of the study, it was expected that any improvement in symptoms would be transient, because no follow-up treatment was offered. The data indicate that this assumption was incorrect. Although the group size was small, the data shown in Figs. 6 through 8 suggest that improvement continued during the first and second months after microcurrent therapy. The treatment schedule needs to be optimized, perhaps delivering fewer treatments the first week followed by weekly and then monthly treatments to determine the maximal achievable benefit. For patients who are just beginning RT, it is possible that an optimal treatment schedule would include administering impedance-controlled microcurrent treatment concurrent with RT. In designing the study, we deliberately excluded the use of any agent or activity that could contribute to the relief of symptoms associated with fibrosis. Because this study has shown benefits attributable to microcurrent therapy alone, it is appropriate to consider combining this therapy with other physical therapy techniques or medications such as pentoxifylline/ vitamin E (10). Seven of the patients who benefited from microcurrent therapy indicated that they had received no benefit from previous physical therapy, but it is possible that the combination might be more effective than either modality alone.

CONCLUSION

Impedance-controlled microcurrent therapy shows promise in improving the range of motion and alleviating other symptoms associated with radiation-induced fibrosis. Studies should be done to validate our preliminary results and to optimize the treatment schedule to achieve longer lasting benefit. Protocols combining microcurrent therapy with physical therapy and/or promising medications could prove to be very beneficial in improving the quality of life for RT patients.