Review of Intrathecal Inflammatory Mass Formation and Catheter Adhesion in Patients with Intrathecal Drug Delivery Systems

Hoi Doan BS1*; Reza EhsanianMD, PHD 2*; Mark Koshkin 3; William Gensler MD 2; Chad Cole MD 4, Matthew Valeriano MD 2, Radhika Grandhe MD 2; Eugene Koshkin MD2

Intrathecal drug delivery systems (IDDS) are indicated for patients with oral therapy-resistant pain, spasticity, and dystonia. This method directly activates spinal opioid receptors, resulting in a significant reduction in systemic opioid dosages and a sustained drug infusion lasting weeks to months1.
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A significant, often overlooked complication is catheter-tip inflammatory mass (IM) development, which can obstruct the catheter, compromising pain management and potentially causing permanent neurological deficits due to spinal cord pressure2.
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Exact cause and pathophysiology remain elusive, with reported prevalence rates varying (possibly underestimated). Diagnosis relies on clinical, imaging, and histopathological evaluation. Treatment options include

Objective:ThispresentationreviewsIDDS-relatedintrathecal inflammatorymassesandadhesions,coveringclinicalaspects, diagnosis,management,andthecurrentunderstandingoftheir pathophysiology. •Method:WefollowedPRISMAguidelines,conductinga systematicreviewofresearchfrom1981to2023indatabases suchasEmbase,PubMed,andGoogleScholar.Wefocusedon adultpatientswithchronicpain,spasticity,orcancerpainwho receivedintrathecaldrugdelivery.Tworeviewers independentlyassessedstudiesmeetingPICOScriteria, resolvingdiscrepanciesthroughdiscussionorthird-party consultation.WeusedCovidenceforsystematicreview management,includingtaskslikeabstractscreening,full-text review,dataextraction,riskofbiasanalysis,anddata exportationforanalysis. •Results:Initially,1544studieswereidentified.Ofthese,976 wereremovedduetoduplication,leaving568uniquestudies. Subsequently,duringtheabstractscreening,367weredeemed irrelevant,leaving201studies.Afterafull-textreview,57 paperswereincludedinthefinalanalysis.

Inthedataset,58%ofpatientsexhibitpolypharmacyintheir IDDS,while42%havemonotherapy. • ThemostcommondiagnosismodalitiesareMRIandCT myelogram. •Amongthe64patientswhounderwentmassexcision,45 improved,16remainedstable,and3worsened. •Among14patientswhostoppedtheinfusionorswitchedto normalsaline,13experiencedsymptomimprovement,while 1worsened. •Amongthe16patientswhohadtheircathetersreplaced,14 showedimprovement,while2remainedthesame. • Therewere24reportsofadherencefromgranulomatothe thecalorspinalcord,butnocasesofdirectcatheteradhesion tothesestructures.

Theaveragetimeforapatientfromsystemimplanttothe diagnosisofIMis4-5years.Therefore,healthcareproviders shouldconsiderschedulingroutinecheck-upsaccordingly. •Giventhewiderangeofpossiblepresentations,it'sessential forclinicianstoengageinproactivepatientmonitoring.This becomesparticularlysignificantwhenaddressingissuessuch asinadequatepaincontrolandtheemergenceofweakness,as theserepresentthemostfrequentlyencounteredsymptoms. •Morphine,hydromorphone,andbupivacainearethemost frequentdrugsinthisdataset.However,giventheircommon usageintheIDDS,significantconclusionscannotbemade. Furtherresearchisnecessarytounderstandtherelationship betweendrugs,dosages,concentrations,andtheformationof IM. •Amongthe24casereportsofgranulomawithadhesionto nearbystructures,nonehaveshownadirectcatheteradhesion tothespinalcord.Toourknowledge,wewillbethefirstto presentsuchacaseatourotherposter.