Mini-CAT 1 Final Draft Name Gagandeep Munday
Clinical Question: Brief description of patient problem/setting (summarize the case very briefly)
Previously on my pediatric rotation a 17-year-old male was brought in by his mother for worsening sweating in armpits and hands. Mother stated that these symptoms of excessive sweating have been persistent for the past 3-4 years. She recently heard of microwave therapy on Facebook and was particularly curious about its efficacy.
PICO Question: Clearly state the question (including outcomes or criteria to be tracked)
In patients with hyperhidrosis does microwave therapy reduce symptoms compared to no/usual therapy?
PICO search terms:
| P | I | C | O |
| Pediatric patients | Microwave therapy | No/usual therapy | Reduction of sweating |
| Hyperhidrosis patients | Microwave therapy | No/usual therapy | Reduction of sweating |
Search tools and strategy used:
Please indicate what data bases/tools you used, provide a list of the terms you searched together in each tool, and how many articles were returned using those terms and filters.
| Database | Terms | Filter | Articles |
| Wiley Online Library | Microwave technology for reduction of sweating in hyperhidrosis patients | Journals Last 10 Years Full Access | 72 |
| Cochrane Library (Wiley) | Microwave technology for reduction of sweating in hyperhidrosis patients | N/A | 1 |
| PubMed | Microwave technology for reduction of sweating in hyperhidrosis patients | Clinical Trial Review Last 10 Years Humans Free Full Text | 43 |
| JAMA | Microwave technology for reduction of sweating in hyperhidrosis patients | Review Research Case Report | 0 |
| ScienceDirect | Microwave technology for reduction of sweating in hyperhidrosis patients | Last 10 Years Review Articles Open Access | 70 |
| Google Scholar | Microwave technology for reduction of sweating in hyperhidrosis patients | Since 2011 Sort by Relevance | 456 |
Results found: 642
Explain how you narrow your choices to the few selected articles.
This is an area of extremely focused research with limited leading to only specific forms of data being available to answer the PICO question. During my research, I needed to peruse through the results to find those articles related to treatment of hyperhidrosis as well as those that studied the utilization of microwave technology. Usually, Google Scholar recommends thousands of articles for other search questions however this search only yielded a few hundred results, unfortunate most of them are not entirely relevant to my search. Initially, a total of 6 articles were initially considered for inclusion. These articles were found from various databases as listed above. These articles were initially selected by assessing the abstract to ensure that they met the criteria of my PICO question. Unfortunately, 2 of the articles were not fully accessible due to the presence of a paywall. They were also not accessible by the York college library database. I narrowed myself down to 4 articles which specifically answered my PICO question with the highest level of evidence that was available and accessible.
Articles Chosen:
| CITATION | Parrish, C., Waldbaum, B., Coleman, D., Blevins, C., Rodgers, K., Lee, B., Ober, C., Hudhud, L., Cox, S., Griffin, C., Chew, S., Chen, B., & Brock, M. (2020). Microwave Thermolysis Reduces Generalized and Social Anxiety in Young Adults With Axillary Hyperhidrosis. Lasers in Surgery and Medicine, 52(9), 842–847. https://doi.org/10.1002/lsm.23229 |
| ABSTRACT | Background and Objectives Microwave treatment is an effective non‐invasive treatment option for primary axillary hyperhidrosis (PAH), but the treatment parameters vary and no histopathological studies have been performed to validate clinical outcomes. This study investigated its efficacy and safety and histopathological changes after a single microwave treatment at the maximum energy level for PAH in Asians. Materials and Methods A prospective, clinical, and histological split‐area randomized controlled trial (RCT) was performed in Japan. Twenty‐six subjects underwent a single microwave treatment at the maximum energy level 5 (5.8 GHz/axilla) on the randomized side of axillae. The primary outcome was the mean difference between both sides in the improvement of modified single‐underarm Hyperhidrosis Disease Severity Scale (msHDSS) scores over the course of the 12‐month study period from baseline. The secondary outcomes were; the percentage of responders with at least a 2‐point drop in the msHDSS score of 3 or 4 group or with a 1‐point drop in the msHDSS score of 2 group; the percentage of responders with at least a 75% reduction in sweat weight over 12 months; recurrence rate; and adverse effects. We also performed a histological assessment for 13 selected subjects. Results Twenty‐four subjects completed the study. There were statistically significant differences in improvement of msHDSS scores between the microwave‐treated and control sides (P < 0.05) from baseline at 0.5, 1, 3, 6, and 12 months. In the msHDSS score of 3 or 4 group, the percentage of responders with at least a 2‐point drop on the microwave‐treated side versus control side was 72.2 versus 11.1% (P < 0.05) at 1 month, 83.3 versus 5.6% (P < 0.05) at 3 months, 61.1 versus 38.9% (P = 0.317) at 6 months and 38.9 versus 16.7% (P = 0.264) at 12 months. The percentage of responders with at least a 75% reduction in sweat weight on the microwave‐treated side versus control side was 75.0 versus 37.5% at 1 month, 75.0 versus 29.2% at 3 months, 83.3 versus 50.0% at 6 months and 70.8 versus 33.3% at 12 months (all P < 0.05). Recurrence on the microwave‐treated side was observed in 4.2% and 12.5% of 24 subjects at 3 and 12 months, respectively. No serious side‐effects were noted. Histology showed the diameter and density of secretory eccrine glands and nerve fiber lengths around eccrine glands were significantly decreased after treatment compared to baseline (P = 0.002, 0.027, 0.003, respectively). Conclusions A single‐session microwave treatment at the maximum energy level significantly improved the PAH of Japanese patients and had minimal side effects. This technique demonstrates that diminished size of secretory eccrine glands and nerve fiber degeneration could be useful markers for predicting the efficacy of the treatment. Lasers Surg. Med. 9999:1–8, 2019. |
| CITATION | Hong HC, Lupin M, O’Shaughnessy KF. Clinical evaluation of a microwave device for treating axillary hyperhidrosis. Dermatol Surg. 2012;38(5):728-735. doi:10.1111/j.1524-4725.2012.02375.x |
| ABSTRACT | Background: A third-generation microwave-based device has been developed to treat axillary hyperhidrosis by selectively heating the interface between the skin and underlying fat where the sweat glands reside. Materials and methods: Thirty-one (31) adults with primary axillary hyperhidrosis were enrolled. All subjects had one to three procedure sessions over a 6-month period to treat both axillae fully. Efficacy was assessed using the Hyperhidrosis Disease Severity Scale (HDSS), gravimetric weight of sweat, and the Dermatologic Life Quality Index (DLQI), a dermatology-specific quality-of-life scale. Subject safety was assessed at each visit. Subjects were followed for 12 months after all procedure sessions were complete. Results: At the 12-month follow-up visit, 90.3% had HDSS scores of 1 or 2, 90.3% had at least a 50% reduction in axillary sweat from baseline, and 85.2% had a reduction of at least 5 points on the DLQI. All subjects experienced transient effects in the treatment area such as swelling, discomfort, and numbness. The most common adverse event (12 subjects) was the presence of altered sensation in the skin of the arm that resolved in all subjects. Conclusion: The device tested provided efficacious and durable treatment for axillary hyperhidrosis. |
| CITATION | Johnson JE, O’Shaughnessy KF, Kim S. Microwave thermolysis of sweat glands. Lasers Surg Med. 2012;44(1):20-25. doi:10.1002/lsm.21142 |
| ABSTRACT | Background and objectives: Hyperhidrosis is a condition that affects a large percentage of the population and has a significant impact on peoples’ lives. This report presents a technical overview of a new noninvasive, microwave-based device for creating thermolysis of sweat glands. The fundamental principles of operation of the device are presented, as well as the design and optimization of the device to target the region where the sweat glands reside. Materials and methods: An applicator was designed that consists of an array of four waveguide antennas, a cooling system, and a vacuum acquisition system. Initially, the performance of the antenna array was optimized via computer simulation such that microwave absorption was maximized near the dermal/hypodermal interface. Subsequently, hardware was implemented and utilized in pre-clinical testing on a porcine model to optimize the thermal performance and analyze the ability of the system to create thermally affected zones of varying size yet centered on the target region. Results: Computer simulation results demonstrated absorption profiles at a frequency of 5.8 GHz that had low amounts of absorption at the epidermis and maximal absorption at the dermal/hypodermal interface. The targeted zone was shown to be largely independent of skin thickness. Gross pathological and histological response from pre-clinical testing demonstrated the ability to generate thermally affected zones in the desired target region while providing protection to the upper skin layers. Conclusions: The results demonstrate that microwave technology is well suited for targeting sweat glands while allowing for protection of both the upper skin layers and the structures beneath the subcutaneous fat. Promising initial results from simulation and pre-clinical testing demonstrate the potential of the device as a noninvasive solution for sweat gland thermolysis |
| CITATION | Glaser DA, Coleman WP 3rd, Fan LK, et al. A randomized, blinded clinical evaluation of a novel microwave device for treating axillary hyperhidrosis: the dermatologic reduction in underarm perspiration study. Dermatol Surg. 2012;38(2):185-191. doi:10.1111/j.1524-4725.2011.02250.x |
| ABSTRACT | Background: Duration of effect and effectiveness limit current options for treating axillary hyperhidrosis. A new microwave procedure for treatment of axillary hyperhidrosis has been tested. Study design/materials and methods: Adults with primary axillary hyperhidrosis were enrolled in a randomized, sham-controlled, blinded study. Subjects were required to have a Hyperhidrosis Disease Severity Scale (HDSS) score of 3 or 4 and baseline sweat production greater than 50 mg/5 min. Procedures were administered using a proprietary microwave energy device that isolates and heats target tissue. Responders were defined as subjects reporting a HDSS score of 1 or 2. Subjects were followed for 6 months (sham group) or 12 months (active group). Results: Thirty days after treatment, the active group had a responder rate of 89% (72/81), and the sham group had a responder rate of 54% (21/39) (P < .001). Treatment efficacy was stable from 3 months (74%) to 12 months (69%), when follow-up ended. Adverse events were generally mild, and all but one resolved over time. Conclusions: The procedure demonstrated statistically significant, long-term efficacy in sweat reduction. As with any new procedure, findings from this first investigational device study identified optimization strategies for the future. |
Summary of the Evidence:
| Author (Date) | Level of Evidence | Sample/Setting (# of subjects/ studies, cohort definition etc. ) | Outcome(s) studied | Key Findings | Limitations and Biases |
| Parrish, C., Waldbaum, B., Coleman, D., Blevins, C., Rodgers, K., Lee, B., Ober, C., Hudhud, L., Cox, S., Griffin, C., Chew, S., Chen, B., & Brock, M. (2020). | Randomized Control Trial | – A prospective, two-center, clinical and histological split area comparative RCT with the axillae of participants randomly assigned 1:1 to a microwave-treated or untreated (control) side, using a random block size of 2 – Twenty-six adults were enrolled, and 24 (3 male, 21 female) – Inclusion criteria healthy, a bilateral PAH diagnosis according to the primary focal hyperhidrosis’ criteria; – included subjects who chose an msHDSS score of at least 2 – excluded subjects who were pregnant or lactating, having concomitant hyperhidrosis therapy, had a previous allergic reaction to lidocaine, contraindicative to epinephrine, had infection near the procedure site, had organic causes of hyperhidrosis like hyperthyroidism, presence of an electrical implant like a pacemaker anywhere in the body, had a history of any cancer, or precancer within the study area – Treatment included marking the axilla with a treatment template, injecting local tumescent anesthesia approximately 80–120 ml of fluid (mixture: 100 ml normal saline, 0.2 ml epinephrine, 1% lidocaine 20 ml, and sodium bicarbonate 2 ml) depending on the axilla size, one microwave treatment using the maximum energy level, 5 (5.8 GHz/axilla, 3.0 seconds). An ice mask was then applied 5 minutes post-treatment | – evaluated six times during the study period: at baseline, 0.5 months post-treatment, and at 1, 3, 6, and 12 months – primary outcome measure was the difference between the treated and control sides in the improvement of msHDSS scores over the entire study period from baseline – Secondary analyses included the same measure calculating the percentage of responders with at least a 2-point drop in the msHDSS score of 3 or 4 group or with a 1-point drop in the msHDSS score of 2 group from baseline on each side – Total recurrence rate was determined as the percentage of relapsed subjects – Considered a failure when the msHDSS score remained similar or worsened from baseline | – The mean baseline msHDSS score was 3.1 +/- 0.8. Seventy-five percent (18/24) of subjects had an msHDSS score of 3 or 4. The mean baseline sweat rate of the treated side (24 axillae) was 69.8 +/- 69.0 mg/5 minutes and the control side (24 axillae) was 52.8 +/-49.3 mg/5 minutes. At baseline, there were no significant differences in msHDSS score and sweat rate (P ¼ 0.33) between the two sides – statistically significant differences in msHDSS score improvement between the treated and control sides (P < 0.05) – Recurrence on the treated side was observed in 4.2% (one subject with a baseline msHDSS score of 2) and 12.5% (one subject with a baseline msHDSS score of 2 and two with baseline msHDSS scores of 4) of 24 subjects at 3 and 12 months, respectively | – participants randomly assigned 1:1 to a microwave-treated or untreated (control) – small sample size, fixed treatment setting, lack of blinding, and most subjects were Japanese women |
| Hong HC, Lupin M, O’Shaughnessy KF. (2012) | Case control | -31 adults were given 1-3 treatments of 3rd gen microwaves to affected axilla over a period of 6 months – All subjects had primary axillary hyperhidrosis evidenced by Hyperhidrosis Dis[1]ease Severity Scale (HDSS) ratings of 3 or 4 and a gravimetric sweat assessment of at least 50 mg in 5 minutes in each axilla – excluded if they had had surgery for axillary hyperhidrosis or botulinum toxin injections in the axillae in the last 12 months | -Primarily recruited axillary hyperhidrosis patients, and subjective as well as quantitative assessments were made to determine efficacy of treatment during the trial period and after 12 months. – primary method for assessing subjects’ level of underarm sweat was subject-reported HDSS score – Gravimetric (weight) assessment of sweat was used as a secondary measure of selection – To obtain overall subject assessment of the procedure, patients were asked to choose a satisfaction rating that described their evaluation of the procedure from the following categories: very satisfied, somewhat satisfied, neutral, somewhat dissatisfied, and very dissatisfied | -After treatment 90.3% of participants had a HDSS score of 1 or 2 which correlates to no noticeable sweating or tolerable sweating. Those who reported a 2, also indicated that they had a 50% reduction in axillary sweat. – Adverse effects such as swelling, discomfort, and numbness were transient and self resolving. – The primary efficacy HDSS result was 90% or higher as measured at all four follow-up visits. – Additional analyses of HDSS at the final 12-month visit shows that 94% (29/31) of the subjects had at least a 1-point drop in HDSS and 55% (17/31) had a 2-point drop or greater in HDSS | – small sample size, fixed treatment setting |
| Johnson JE, O’Shaughnessy KF, Kim S (2012) | In-vitro study | – Testing was performed on a porcine model which has been shown to be very similar to humans – Industry-standard three-dimensional microwave simulation tool (CST Microwave Studio, CST of America, Inc., Boston, MA) was utilized to perform the optimization of the electromagnetic response – Using the anatomy of the axilla as an example, the epidermal and dermal layers were modeled as a single 1.75 mm thick slab. | – Animals were anesthetized and a grid was created on the left and right flank surfaces. – Each rectangular area of the grid was a test location for a single treatment. Utilizing a 158C coolant temperature and an approximate 30 W antenna power per channel, microwave energy levels of 599, 630, and 756 J were utilized. N | -3rd gen microwaves have max absorption at the dermal/hypodermal region regardless of skin thickness. – Epidermis has low absorption of microwaves while the dermis/hypodermis is targeted, indicating some level of protection to epidermis | – Low level of evidence |
| Glaser DA, Coleman WP 3rd, Fan LK, et al. (2012) | Randomized Control trial | -Recruited participants with a baseline HDSS of 3 or 4 – 81 participants received treatment with microwaves, response was compared to 39 participants who received “sham” treatment. The intervention group was followed for 12 months while the sham group was followed for 6 months – subjects were excluded if they had ever had prior surgery for PAH or botulinum toxin injections to treat PAH within the past 12 months | – primary method of assessing level of underarm sweat was subject-reported HDSS score -Measurements were taken in a normal-temperature room with subjects at rest. Axillae were wiped with gauze or absorbent towels before the test, and a preweighed filter paper was placed in each axilla for 5 minutes, after which the difference in weight was calculated in milligrams. | – Responders were defined as those who had a HDSS of 1 or 2 after treatment, 89% of participants in the interventional group had a response to microwave therapy compared to 54 of those receiving sham treatment. – Results from microwave therapy was maintained for 69% of participants after 12 months | – limited sample size – some of the outcomes and baseline assessments are self reported |
Conclusion(s):
– Briefly summarize the conclusions of each article, then provide an overarching conclusion.
Parrish, C., Waldbaum, B., Coleman, D., Blevins, C., Rodgers, K., Lee, B., Ober, C., Hudhud, L., Cox, S., Griffin, C., Chew, S., Chen, B., & Brock, M. (2020): The percentage of responders with at least a 75% reduction in sweat weight on the microwave treated side versus control side was 75.0 versus 37.5% at 1 month, 75.0 versus 29.2% at 3 months, 83.3 versus 50.0% at 6 months and 70.8 versus 33.3% at 12 months. Improvements after one treatment at maximum energy were rapid and sustained, demonstrating efficacy and safety.
Hong HC, Lupin M, O’Shaughnessy KF. (2012): After treatment 90.3% of participants had a HDSS score of 1 or 2 which correlates to no noticeable sweating or tolerable sweating. Those who reported a 2, also indicated that they had a 50% reduction in axillary sweat. Adverse effects such as swelling, discomfort, and numbness were transient and self-resolving.
Johnson JE, O’Shaughnessy KF, Kim S (2012): 3rd gen microwaves have max absorption at the dermal/hypodermal region regardless of skin thickness. Epidermis has low absorption of microwaves while the dermis/hypodermis is targeted, indicating some level of protection to epidermis. Demonstrates the specificity that microwaves have for the dermis/hypodermis where the sweat glands reside.
Glaser DA, Coleman WP 3rd, Fan LK, et al. (2012): 89% of participants in the interventional group had a response to microwave therapy compared to 54 of those receiving sham treatment. Results from microwave therapy was maintained in 69% of participants after 12 months.
Clinical Bottom Line:
Please include an assessment of the following:
– Weight of the evidence – summarize the weaknesses/strengths of the articles and explain how they factored into your clinical bottom line (this may recap what you discussed in the criteria for choosing the articles)
– Magnitude of any effects
– Clinical significance (not just statistical significance)
– Any other considerations important in weighing this evidence to guide practice – If the evidence you retrieved was not enough to conclude an answer to the question, discuss what aspects still need to be explored and what the next studies will have to answer/provide (e.g. larger number, higher level of evidence, answer which sub-group benefits, etc)
PICO Question: In patients with hyperhidrosis does microwave therapy reduce symptoms compared to no/usual therapy?
Clinical Bottom Line: The evidence that was available and accessible suggests that patients with hyperhidrosis report a significant decrease in the degree of sweating after exposure to microwave therapy.
Weight of the Evidence (With Rank (bolded number) and Explanation):
1 Parrish, C., Waldbaum, B., Coleman, D., Blevins, C., Rodgers, K., Lee, B., Ober, C., Hudhud, L., Cox, S., Griffin, C., Chew, S., Chen, B., & Brock, M. (2020): This is a very recent randomized control trial that was published in 2020. I weighed this article as the strongest since it was published more recently than the RCT by Glaser et al. However, this RCT does have a much smaller sample size than the RCT by Glaser et al. Also, most of the participants are a very niche group of mainland Japanese women. There are some concerns with it not being double blind RCT however the evidence regarding the efficacy remains compelling. Similarly, to Glaser et al and Hong et al, this recent RCT demonstrates that microwave therapy for axillary hyperhidrosis can remain efficacious for up to 12 months.
2 Glaser DA, Coleman WP 3rd, Fan LK, et al (2012): This is an older randomized control trial. I chose this article because it was a higher grade of evidence compared to the below two articles. This RCT demonstrates that microwave therapy is efficacious in hyperhidrosis patients with a HDSS of at least 3 or 4. It had the largest sample size compared to the RCT by Parrish et al. Of the 81 participants in the interventional group, 89% had an efficacious response to microwave therapy with results persisting for 12 months. I weighed this article higher than the ones below because it is higher grade of evidence than the below case control and in-vitro study. However, I ranked it lower than the above RCT because this article was published in 2012.
3 Hong HC, Lupin M, O’Shaughnessy KF. (2012): This is a case control which is a lower grade of evidence than the above RCTs. I chose this article because it is one of the few articles that focused on all aspects of the course of treatment with microwaves. While it is a lower level of evidence article, this case control study gathered both qualitative and quantitative evidence. Most importantly it shows that this method is relatively safe for treating axillary hyperhidrosis with results persisting for 12 months.
4 Johnson JE, O’Shaughnessy KF, Kim S (2012): I rated this in-vitro study as the weakest in terms of evidence in comparison to the other articles used in this min-CAT. However, the evidence remains efficacious because such studies are always necessary especially when testing a novel form of treatment. These researchers utilized porcine animal skin models as test subjects, which have been shown to be anatomically similar human skin.
Magnitude of Effects:
All forms of evidence in the 4 articles discussed thus far demonstrate a high degree of efficacy and safety in microwave therapy.
Clinical Significance:
A summation of the findings from the above articles demonstrates that patients with axillary hyperhidrosis would have significant benefits undergoing microwave therapy. This form therapy is not only efficacious but also relatively safe for treating hyperhidrosis. Patients self-reported a very noticeable decrease in the degree to which they sweat after exposure to this form of therapy, with HDSS scores dropping from 4 to 1. In perspective a score of one signifies no noticeable sweating, while a score of four signifies that the sweating is intolerable and interferes with daily activities. Such changes are clinically significant, especially since microwave therapy can be efficacious for up to 12 months in most of the treated patients within the RCTs and the case control study discussed above.
Other Considerations:
The next step in evaluating the efficacy of microwave therapy are systematic reviews to statistically interpret the evidence the of RCTs and cohort studies. This would offer higher grade of evidence and address the sample size issues that the above studies had. By increasing the sample size, we can decrease the standard of error. A meta-analysis would illuminate the presence of any confounding variables and biases that might be influencing the data. Further comparison studies need to be made between microwave therapy, and more standard therapies such as topical prescription antiperspirants.
