This document addresses a wireless capsule for the evaluation of suspected gastric and intestinal motility disorders (SmartPill™ Motility Testing System [Medtronic, Minneapolis, MN]). The capsule was designed to measure pH, temperature and pressure throughout the gastrointestinal tract and transmits measurements via radio signals to an external recording device. In the stomach, the SmartPill has been used to assess gastric emptying in individuals with suspected gastroparesis. In the intestine, the SmartPill has been used to assess small and large bowel transit times in those with chronic constipation or other motility disorders. The device is also referred to in this document as a wireless motility capsule.
Note: Please see the following related documents for additional information:
Investigational and Not Medically Necessary:
A wireless capsule for the evaluation of suspected gastric motility disorders (SmartPill Motility Testing System) is considered investigational and not medically necessary for all conditions.
A wireless capsule for the evaluation of suspected intestinal motility disorders (SmartPill Motility Testing System) is considered investigational and not medically necessary for all conditions.
Wireless Motility Capsule for the Evaluation of Suspected Gastroparesis
The American Gastroenterological Association (AGA) (2013) has identified gastric emptying scintigraphy (GES) of a solid-phase meal as the standard for the diagnosis of gastroparesis. Scintigraphy studies involve the ingestion of a radiolabeled meal followed by serial images to identify the percentage of the meal retained at 2 and 4 hours. In contrast, the wireless motility capsule estimates the gastric emptying time (GET) based on the time from ingestion to an abrupt rise in the pH, signifying that the capsule has passed from the acid environment of the stomach to the alkaline duodenum. Validation of the wireless motility capsule as an alternative to scintigraphic gastric emptying studies requires directly comparative studies of individuals with a variety of symptoms which are interpreted in a blinded fashion.
Kuo and colleagues (2008) enrolled 87 healthy subjects and 61 with known gastroparesis who simultaneously ingested the wireless capsule and a radiolabeled meal, permitting a head-to-head comparison. At 4 hours the correlation between the two techniques was 0.73, which exceeded the prespecified target correlation. However, the study did not indicate whether or not the GES and GET were interpreted in a blinded fashion. In addition, the study only enrolled subjects with a known diagnosis of gastroparesis and not a broader group with suspected gastroparesis. There was no discussion of how the diagnostic information was used in the management of the condition.
Sarosiek and colleagues (2010) reported on a secondary analysis of regional and whole gut transit times (WGTT) obtained from the previous study by Kuo (2008). Data from 100 of the original subjects (66 healthy controls and 34 subjects with GP [15 diabetic and 19 idiopathic]) who had swallowed the wireless capsule together with a standardized meal were analyzed. Colon transit time (CTT), GET, small bowel transit time (SBTT), and WGTT were calculated using the wireless motility capsule. Gastric emptying time (GET), CTT and WGTT but not SBTT were noted to be longer in gastroparetics than in controls. Eighteen percent of gastroparetics had delayed WGTT. Both diabetic and idiopathic subjects with gastroparesis had significantly slower WGTT in addition to significantly slower GET than healthy controls. Diabetic gastroparetics also had significantly slower CTT than healthy controls.
Kloetzer and colleagues (2010) hypothesized that the wireless motility capsule can differentiate antroduodenal pressure profiles between healthy people and those with upper gut motility dysfunctions. This multicenter study analyzed differences in the phasic pressure profiles of the stomach and small intestine in healthy and gastroparetic subjects. Data from 71 healthy and 42 subjects with a history of gastroparesis were obtained. A total of 12 subjects (6 healthy and 6 gastroparetic) were excluded from the study because of incomplete pressure data resulting from failure of subjects to wear the receiver at all times. The number of contractions (Ct), area under the pressure curve (AUC), and motility index (MI) were analyzed for 60 minutes before and after gastric emptying of the capsule. Study results demonstrated that differences were observed between healthy and gastroparetic subjects for Ct and MI. Median values of the motility parameters in gastric window were Ct=72, MI=11.83 for healthy and Ct=47, MI=11.12 for gastroparetics. In the small bowel, median values were Ct=144.5, MI=12.78 for healthy and Ct=93, MI=12.12 for gastroparetics. The subgroup of diabetic subjects with gastroparesis (16 subjects) showed significantly lower Ct and MI compared with healthy subjects in both gastric and small bowel windows, while idiopathic gastroparetic subjects (26 subjects) demonstrated a trend towards significant differences only in the gastric window.
Additional small studies have also addressed the use of the wireless motility capsule as a research tool in studying such parameters as intragastric pH (Hasler, 2008) or antroduodenal manometry (Cassilly, 2008).
Wireless Motility Capsule for the Evaluation of Suspected Chronic Constipation
Chronic constipation may be associated with a prolonged CTT or WGTT, both of which are typically measured using radiopaque markers (ROM). Validation of the wireless motility capsule to evaluate CTT or WGTT requires directly comparative studies with conventional ROM with blinded interpretation of results. In addition, the diagnosis of chronic constipation is based predominantly on clinical symptoms; therefore, studies should ideally document how measurements of transit times contribute to management of the condition (i.e. clinical utility).
Rao and colleagues (2009) compared transit times in both constipated (n=78) and healthy subjects (n=87) measured simultaneously with the wireless motility capsule and ROM. The wireless motility capsule estimated the SBTT based on pH changes as the capsule entered the duodenum (increase in pH) and then passed into the cecum (decrease in pH). The CTT was based on the time interval between entry into the cecum and the capsule exit from the body. Serial plain abdominal films were used to assess the movement of ROM. Correlation of the wireless motility capsule's colonic transit with ROMs expelled on day 2/day 5 was r=0.74/r=0.69 in the constipated subjects, and r=0.70/r=0.40 in the control group, respectively. This study did not report whether or not the results were interpreted in a blinded fashion, and there was no discussion of how the diagnostic information was used in the management of the condition.
Magbool and colleagues (2009) compared the wireless motility capsule with whole gut transit scintigraphy to determine if the SmartPill system could serve as a test for measurement of whole gut motility and transit. While the authors suggested that the device may be capable of assessing both GET and whole gut transit (to evaluate individuals for constipation), only 10 subjects, described as healthy and asymptomatic, were studied.
The largest study was reported by Camilleri and colleagues (2010) and compared the wireless motility capsule to ROM measurements of colon transit. Of 208 subjects recruited, 180 (20 males and 138 females) with symptoms of self-reported constipation were enrolled in the multicenter trial. The study participants ingested both the wireless motility capsule and ROM. Of these 180, 13 participants were excluded from the assessment due to non-compliance or device malfunction and 9 others were excluded due to their intake of prohibited medications such as antibiotics, laxatives, opiates and a proton pump inhibitor. Data from a total of 158 subjects were used to compare ROM and wireless motility capsule colonic transit time (CTT) and the wireless motility capsule's combined small and large bowel transit time (SLBTT). In 4 of these subjects, SLBTT could not be estimated due to lack of a typical change in pH that is used to identify the time of exit of the capsule and in 1 subject the CTT value was missing due to the lack of a typical ileocecal junction pH change and consequently the inability to identify the start of colonic transit. As a result, the assessment of CT was based on comparisons between CTT by wireless motility capsule and ROM in 157 subjects, and comparison between SLBTT by wireless motility capsule and ROM in 154 subjects. Study results indicated that 59 of 157 subjects had delayed ROM colon transit. Overall device agreement was reported as 86%. There were correlations reported between ROM and wireless motility capsule transit and between ROM and combined SLBTT. Estimates of CTT and SLBTT were calculated by a team reported as being blinded to the ROM transit results. Adverse events reported during the trial included the inability of 2 subjects to swallow the wireless motility capsule and 1 case each of abdominal cramping, nausea and loose or soft stools recorded as possibly related to the wireless motility capsule. The authors noted potential pitfalls of using all capsules to measure gut transit included: "technical failures, inability to swallow the capsule, the potential for non-passage of or intestinal obstruction by the capsule in stenosing gut disorders, and greater cost relative to the ROM transit method."
Wireless Motility Capsule for the Evaluation of Suspected Upper and Lower Gastrointestinal (GI) Motility Disorders
Rao and colleagues (2010) examined the diagnostic utility of the wireless motility capsule in individuals with suspected upper and lower gastrointestinal dysmotility. A total of 86 subjects with symptoms of dysmotility (abdominal pain, nausea, vomiting, bloating, fullness after meals, constipation, straining, feeling of incomplete evacuation) and normal endoscopic/radiologic evaluations were assessed with both conventional motility tests (CMT) and the wireless motility capsule. The diagnostic utility of the wireless motility capsule was retrospectively assessed by examining device agreement and new information compared with CMT. Study subjects were classified into two subgroups on the basis of major symptom(s): lower GI (LGI=50) and upper GI (UGI=36). Clinical suspicion was confirmed in 52% and 66% of study subjects, respectively, and the authors stated there was good device agreement between the wireless motility capsule and CMT in 76% and 81% in the LGI and UGI groups, respectively. There was new diagnostic information with the wireless motility test in 53% of the LGI (p=0.006) and 47% of the UGI group (p=0.001). The wireless motility capsule detected generalized motility disorder in 44 (51%) subjects and influenced management in 30% of LGI and 88% of UGI subjects. Study limitations noted by the authors included potential bias of a retrospective study, the inclusion of subjects with more severe symptoms than are typically seen at a tertiary care center, and the tests were not carried out simultaneously which could result in discrepancy between the test results.
Kuo and colleagues (2011) evaluated the wireless motility capsule in a retrospective study of 83 subjects with suspected gastroparesis, intestinal dysmotility, or slow transit constipation. Databases at two referral centers for gastrointestinal motility were accessed. Wireless motility capsule transits were analyzed and isolated regional delays were observed in 32% (9% stomach, 5% small bowel, 18% colon). Transits were normal in 32% and showed generalized delays in 35%. Symptom profiles were similar with normal transit, isolated delayed gastric, small intestinal and colonic transit, and generalized delay. Compared to conventional tests, wireless motility capsule showed discordance in 38% and provided new diagnoses in 53%. Wireless motility testing reportedly influenced clinical management in 65 subjects (67%) (new medications 60%; modified nutritional regimens 14%; surgical referrals 6%) and eliminated needs for testing not already done including gastric scintigraphy (17%), small bowel barium transit (54%), and radiopaque colon marker tests (68%). A significant limitation of this study was that all subjects were from two academic centers specializing in managing severe dysmotility syndromes and would therefore differ from a representative community sample. Also of note, this retrospective investigation involved analyses of preexisting databases and data recording was not standardized, therefore reporting of a lack of a specific symptom or test result may not be the equivalent of symptom absence or non-performance of the test.
Tran and colleagues (2012) reported that clinical studies have shown wireless motility capsule-measured GI transit times can distinguish those with motility abnormalities similarly to conventional testing. However, further noted is that in comparison with manometry, interpretations of pressure measurements obtained by the wireless motility capsule are limited by an inability to detect a peristaltic pressure wave front, and further investigation is required to develop clinical applications.
Arora and colleagues (2015) performed a single center retrospective chart review of 161 individuals who underwent wireless motility capsule testing. Wireless motility capsule testing was abnormal in 109 (67.7%) subjects. From the abnormal cases, 17 (15.6%) individuals had isolated delayed gastric emptying, 13 (11.9%) had isolated delayed small bowel transit, and 25 (22.9%) had isolated delayed large bowel transit. Multiregional (upper and lower) dysmotility was diagnosed in 54 (49.5%) cases. Of note, the presence or absence of various individually-reported symptoms by history did not predict an abnormal study. The authors concluded that "wireless motility capsule can be a useful diagnostic test in patients with suspected multiregional GI dysmotility." However, they also reported that a limitation of the study was that that they "did not attempt to assess if the results of the wireless motility capsule study changed the patients' outcome or management as the information needed was difficult to obtain in our settings and may be unreliable."
A retrospective chart review of 100 diabetics who had undergone wireless motility capsule testing at a single institution between the years 2010 to 2015 was performed by Rouphael and colleagues (2017). Of the original 103 subjects, 3 were excluded due to either a retained capsule (n=1) or missing data secondary to device failure (n=2). A total of 72% of subjects had abnormal wireless motility capsule testing, of which 40% (n=29) had multiregional dysmotility with 6.9% (n=5) having delayed transit in all three GI tract segments. Information related to subsequent clinical management post testing was available for 47 subjects. The remaining 53 subjects were excluded from the analysis due to loss to follow-up or incomplete information related to treatment change or response to therapy. Of the 47 subjects, wireless motility capsule testing was abnormal in 70% (n=33) and treatment changes were made in 73% (n=24) of those with gut dysmotility. Multiple limitations of this study included the retrospective nature of the analysis and small sample size.
Influence of Variables
In 2015, Wang and colleagues investigated the effect of variables such as gender, age, testing protocol and study country on regional GI transit times and associated pH values using the wireless motility capsule. Over a 6.5 year period between March 2005 and November 2011, 215 healthy volunteers from the United States and Sweden were evaluated. Data was supplied by the SmartPill Corporation for studies performed in the United States, and by principal investigators for studies performed in Sweden. Two different study protocols were used; however, all subjects were evaluated after an overnight fast.
Significant findings included:
The authors concluded that "standardization of testing is crucial for cross-referencing in clinical practice and future research."
A 2008 consensus statement of the American Neurogastroenterology and Motility Society indicates that the impact of the device on the management of individuals with presumed upper GI dysmotility has not been studied.
Rao and colleagues (2011), in a position paper of the American and European Neurogastroenterology and Motility Societies reviewed diagnostic tools used to assess regional or WGTT including the wireless motility capsule. The authors recommended the wireless motility capsule for the following:
Confounding issues or disadvantages involving the wireless motility capsule reported in the position paper included:
The recommendations made by the American and European Neurogastroenterology and Motility Societies for the wireless motility capsule are limited by supporting evidence which is insufficient to fully establish the clinical utility or accuracy of the SmartPill. In addition, significant confounding issues or disadvantages of the device have been reported.
A 2013 AHRQ comparative effectiveness review: Wireless Motility Capsule Versus Other Diagnostic Technologies for Evaluating Gastroparesis and Constipation reported:
Based on current literature, the wireless motility capsule appears to be accurate in detection of gastroparesis and slow-transit constipation and may provide increased diagnostic gain as compared with standard motility testing.
However, AHRQ further noted:
Evidence is insufficient to determine whether use of the wireless motility capsule will improve outcomes of care. Although we found limited evidence on the impact of wireless motility capsule testing on patient outcomes, we should acknowledge that it is also true that little evidence exists on the impact of conventional motility testing.
A 2013 American College of Gastroenterology guideline for management of gastroparesis indicates that the wireless motility capsule requires further validation before it can be considered as an alternative to scintigraphy for diagnosis of gastroparesis.
Acceptance of trial data confirming usefulness of wireless motility capsule testing in suspected gastric motor disorders has been limited by small sample sizes and design limitations (Hasler, 2014). Larger well designed studies are needed that compare results with use of this device (using an established protocol and cutoff values) with the current standard test. Evaluation of cases with discordant results would be of particular value. Ideally, these studies should be linked to therapeutic decisions and to meaningful clinical outcomes.
The SmartPill has been cleared for marketing by the U.S. Food and Drug Administration (FDA). According to the FDA 510(k) documents, the SmartPill is indicated for use in evaluating individuals with suspected delayed gastric emptying (gastroparesis) and also for the evaluation of colonic transit in those with chronic constipation. The SmartPill Motility Testing System (formerly known as SmartPill GI Monitoring System) measures pH, pressure and temperature throughout the gastrointestinal tract. This data is then transmitted from the capsule via radio signal to an individually-worn data receiver and downloaded to a computer in the physician's office for analysis and review. The recorded physiological measurements are used to determine GET, total transit time, and combined small-large bowel transit time. In addition, pressure contraction patterns from the antrum and duodenum are used to calculate motility indices. Delayed gastric emptying is implicated in such disorders as idiopathic and diabetic gastroparesis and functional non-ulcer dyspepsia.
Gastric Emptying Scintigraphy (GES): A type of test which uses a radio-labeled meal to measure gastric emptying.
Gastroparesis: A condition where there is delayed gastric emptying.
The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.
When Services are Investigational and Not Medically Necessary:
When the code describes a procedure indicated in the Position Statement section as investigational and not medically necessary.
|91112||Gastrointestinal transit and pressure measurement, stomach through colon, wireless capsule, with interpretation and
Peer Reviewed Publications:
Government Agency, Medical Society, and Other Authoritative Publications:
SmartPill GI Monitoring System
SmartPill Motility Testing System
Wireless Capsule for Measuring Gastric EmptyingWireless Motility Capsule (WMC)
The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.
|Reviewed||08/03/2017||Medical Policy & Technology Assessment Committee (MPTAC) review. Rationale and References sections updated.|
|Revised||08/04/2016||MPTAC review. Description, Rationale, Background, Reference and Index sections updated. Position statement updated with new device name (SmartPill GI Monitoring System changed to SmartPill Motility Testing System). Removed ICD-9 codes from Coding section.|
|Reviewed||08/06/2015||MPTAC review. Description, Rationale, Background and Reference sections updated.|
|Reviewed||08/14/2014||MPTAC review. Description, Rationale and Reference sections updated.|
|Reviewed||08/08/2013||MPTAC review. Rationale and Reference sections updated.|
|01/01/2013||Updated Coding section with 01/01/2013 CPT changes; removed 0242T deleted 12/31/2012.|
|Reviewed||08/09/2012||MPTAC review. Rationale, Reference and Index sections updated.|
|Reviewed||08/18/2011||MPTAC review. Rationale, Definition and Reference sections updated.|
|Reviewed||08/19/2010||MPTAC review. Updated title of document by removing brand name. Clarified initial position statement by adding the word "motility". Description, Rationale, Background, References and Index updated. Updated Coding section with CPT changes effective 01/01/2011.|
|Revised||11/19/2009||MPTAC review. Description, rationale coding and references updated. Original position statement updated to address a wireless capsule for the evaluation of suspected gastric disorders. Added a position statement to address a wireless capsule for the evaluation of suspected intestinal motility disorders. Updated title of document to include intestinal motility.|
|Reviewed||11/20/2008||MPTAC review. Position statement clarified by adding the wording "A wireless capsule for measuring gastric emptying" to describe SmartPill GI Monitoring System. No change to position stance. Description, rationale, references, and index updated. Definitions added. Title of document changed from "SmartPill GI Monitoring System®" to "Wireless Capsule for Measuring Gastric Emptying (SmartPill GI Monitoring System® )".|
|Reviewed||11/29/2007||MPTAC review. Rationale and references updated. The phrase "investigational/not medically necessary" was clarified to read "investigational and not medically necessary."|
|New||12/07/2006||MPTAC initial document development.|