Management of Intrathecal Catheter-Tip Inflammatory Masses: An Updated 2007 Consensus Statement From An Expert Panel

Scar Tissue Catheter Tip Occlusion From an Intrathecal Baclofen Delivery: A Case Report and Review of the Literature

Intrathecal morphine is associated with the complication of catheter tip granuloma which causes symptoms of decreased pain control, increased required dose, and neurological deficit. Catheter tip granulomas from intrathecal baclofen are thought to never occur because of the mechanism by which intrathecal morphine causes granulomas. We present a case of an intrathecal baclofen induced scarring of a catheter tip with clinical characteristics similar to some symptoms of granuloma. A 66-year-old woman with multiple sclerosis induced spasticity was partially controlled with intrathecal baclofen delivery at an extremely high dose of 1638 micrograms per day. She presented in the hospital with symptoms of withdrawal from intrathecal baclofen and required an emergency revision of her baclofen pump. Replacement of the catheter demonstrated complete occlusion of the catheter tip by scar tissue. Following surgery, her spasticity was well-controlled at the much lower dose of 200 micrograms per day. Intrathecal baclofen delivery can cause catheter tip scarring which causes some symptoms similar to catheter tip granuloma. Early recognition of these signs of catheter tip occlusion could help prevent progression to withdrawal.

Spinal cord and brain concentrations of riluzole after oral and intrathecal administration: A potential new treatment route for amyotrophic lateral sclerosis

Riluzole is the only treatment known to improve survival in patients with Amyotrophic Lateral Sclerosis (ALS). However, oral riluzole efficacy is modest at best, further it is known to have large inter-individual variability of serum concentration and clearance, is formulated as an oral drug in a patient population plagued with dysphagia, and has known systemic side-effects like asthenia (limiting patient compliance) and elevated liver enzymes. In this context, we postulated that continuous intrathecal (IT) infusion of low doses of riluzole could provide consistent elevations of the drug spinal cord (SC) concentrations at or above those achieved with oral dosing, without increasing the risk for adverse events associated with systemic drug exposure or off-target side effects in the brain. We developed a formulation of riluzole for IT delivery and conducted our studies in purpose-bred hound dogs. Our non-GLP studies revealed that IT infusion alone was able to increase SC concentrations above those provided by oral administration, without increasing plasma concentrations. We then conducted two GLP studies that combined IT infusion with oral administration at human equivalent dose, to evaluate SC and brain concentrations of riluzole along with assessments of safety and tolerability. In the 6-week study, the highest IT dose (0.2 mg/hr) was well tolerated by the animals and increased SC concentrations above those achieved with oral riluzole alone, without increasing brain concentrations. In the 6-month study, the highest dose tested (0.4 mg/hr) was not tolerated and yielded SC significantly above those achieved in all previous studies. Our data show the feasibility and safety profile of continuous IT riluzole delivery to the spinal cord, without concurrent elevated liver enzymes, and minimal brain concentrations creating another potential therapeutic route of delivery to be used in isolation or in combination with other therapeutics."

Symptomatic Intrathecal Catheter Tip Granuloma Formation With Ultralow-Dose and Low-Concentration Morphine Infusion: A Case Report and Review of Literature

OBJECTIVES

This study aimed to describe catheter tip granuloma (CTG) formation in a patient on ultralow-dose, low-concentration morphine via intrathecal (IT) drug delivery system (IDDS) and to review literature for reports of IT granuloma formation and association with drug type, drug dose, and drug concentration.

MATERIALS AND METHODS

This review describes diagnosis and management of a patient with CTG on ultralow-dose, low-concentration morphine. PubMed data base search was conducted from January 1990 to July 2021 for original articles on CTG formation in humans getting intrathecal analgesics. Data were extracted on indications for IDDS, time to detect CTG, and type of drug/s with drug doses and concentrations. Percentages and average with range for age, sex, duration of infusion, drug doses, and drug concentrations were calculated.

RESULTS

We describe CTG formation and spinal cord compression with worsening of sensorimotor deficits in a patient receiving intrathecal morphine at ultralow dose (0.6 mg/d) and low concentration (1.2 mg/mL), which is the lowest reported morphine dose associated with CTG in the literature. Our literature review shows all IT drugs have the potential for granuloma formation, and there is no drug with granuloma-inhibiting effect.

CONCLUSIONS

There is no drug, dose, or concentration that has granuloma-sparing effect. It is imperative to maintain vigilance for potential CTG in all patients with IDDS. Routine monitoring and prompt evaluation for any unexplained symptoms or change in neurologic status from baseline is critical in early detection and treatment of CTG.

Restoration of rostral cerebrospinal fluid flow to solve treatment failure caused by obstruction in long-term intrathecal baclofen administration

Objects: We describe five traumatic spinal cord injury (SCI) patients with an intrathecal baclofen administration (ITB) failure caused by a rostral CSF flow obstruction referred to our expert center between January 2014 and January 2019. We discuss the diagnostic workup, rostral CSF flow obstruction as the cause of the ITB failure and treatment.Methods: When we could not determine the cause of the ITB failure through the patient's history, physical spasticity examination, pump readout, absence of fluid in the pump reservoir during aspiration, or plain radiography, we performed pump catheter access port (computed tomography [CT]) myelography. When CT myelography did not reveal the diagnosis, we used scintigraphy. In an obstruction, we aimed for CSF flow restoration. In three cases, we conducted a laminectomy with microsurgical adhesiolysis. In two of these patients, we could not achieve CSF flow restoration; thus, we placed an intradural catheter bypass. Recently, in three patients, we applied a less invasive technique of percutaneous fenestration of the obstruction.Results: In one case, we performed a successful catheter replacement. In another case using surgical adhesiolysis, spasticity control was complete. In two cases, we could obtain improvement with an additional intradural bypass, followed by a percutaneous fenestration of the obstruction, resulting in further improved CSF flow restoration. In one case, percutaneous fenestration was the first line of treatment. In all cases with percutaneous fenestration, we experienced spasticity control.Conclusion: Preliminary results showed that the restoration of rostral CSF flow might result in an effective ITB treatment in patients with an intrathecal obstruction.

A Patient with an Intradural Tumor: An Unexpected Finding

Chronic back pain patients may require escalating doses of systemic opioids. In refractory cases, implantation of an intrathecal drug delivery system (IDDS) may provide effective relief of pain and improve overall function. This system infuses opioid directly into the cerebrospinal fluid via a catheter. While efficacious, it can be associated with complications, one of the most severe being the formation of a catheter-tip granuloma that can lead to permanent neurological deficits. We present a case of a 38-year-old male with an IDDS for pain related to retroperitoneal fibrosis, who began developing worsening back pain along with new-onset lower extremity weakness. A catheter-tip granuloma was suspected, and the patient was advised to obtain emergent spine imaging. He was non-compliant until the point of becoming wheelchair bound, whereupon imaging was finally obtained. Magnetic resonance imaging revealed an intradural mass causing spinal cord compression. After emergent surgical resection, pathology revealed a malignant tumor. Any patient with IDDS and escalating pain levels or new neurological deficits needs urgent neuroimaging to rule out catheter-tip granuloma. However, as this case demonstrates, the differential diagnosis should remain broad and always include neoplasm or abscess. 

Intrathecal drug delivery for pain management: recent advances and future developments

Introduction: Chronic pain conditions of malignant and non-malignant etiology afflict a large group of the population and pose a vast economic burden on society. Intrathecal drug therapy is a viable treatment option in such patients who have failed conservative medical measures and less invasive pain management procedures. However, the clinical growth of intrathecal therapy in managing intractable chronic pain conditions continues to face many challenges and is likely underutilized secondary to its high-complexity and lack of understanding. Areas covered: This review will briefly discuss the history of intrathecal drug delivery systems (IDDS), cerebrospinal fluid (CSF) flow dynamics, types of IDDS, indications and patient profile suitable for this therapy, and risks and complications related to IDDS. We will also discuss challenges faced by physicians utilizing this therapy and the future changes that are needed for making this treatment modality more efficacious. Expert opinion: IDDS offer an effective therapy for pain control in patients suffering from chronic intractable pain conditions. These devices provide a safer alternative to oral opioid medications with reduced systemic side effects. Adherence to best practices and continued clinical and basic science research is important to ensure continuing success of this therapy.

Intrathecal catheter-associated inflammatory mass in a neurofibromatosis type-1 patient receiving fentanyl and bupivacaine

Background:

Catheter-associated inflammatory masses (CIMs) are a rare but serious complication of intrathecal drug delivery devices. CIM formation is influenced by local medication concentration, which is determined in part by flow dynamics at the catheter tip. Underlying spinal pathologies, such as neoplasms, may alter flow at the catheter tip, thereby contributing to CIM formation. Moreover, they may also complicate the clinical and radiologic diagnosis of a CIM.

Case Description:

A 36-year-old man with neurofibromatosis type 1 presented to our emergency department with complaints of increased back pain and leg weakness. To treat pain secondary to his multiple spinal masses, he had previously undergone placement of an implantable drug delivery system, which infused a compounded drug of fentanyl and bupivacaine. Imaging studies depicted numerous masses consistent with neurofibromatosis, including a compressive mass located circumferentially at the porous catheter terminus and proximal to the catheter tip. Surgical removal of this mass was performed; pathologic findings were consistent with a catheter tip granuloma.

Conclusions:

In the described case, CIM formation likely resulted from a combination of, 1) an unusually high fentanyl concentration, and, 2) altered infusate flow due to spinal neurofibromas. Consideration of underlying spinal pathologies, particularly mass lesions, is critical to the management of intrathecal drug delivery devices.

The Relationship Between the Mechanisms of Action and Safety Profiles of Intrathecal Morphine and Ziconotide: A Review of the Literature

OBJECTIVE

To better characterize safety profiles associated with the intrathecal (IT) administration of morphine and ziconotide and discuss how they relate to mechanisms of action.

METHODS

Published data were evaluated to identify potential relationships between safety profiles of IT morphine and IT ziconotide and their mechanisms of action.

RESULTS

Potentially severe and clinically relevant adverse events (AEs) associated with IT morphine include respiratory depression, tolerance, and granuloma formulation, whereas IT ziconotide is associated with neuropsychiatric AEs, such as cognitive impairment, hallucinations, and changes in mood or consciousness, particularly with high doses and rapid titration. AEs associated with these IT therapies may result from spread of the medication out of the IT space into areas of the central and peripheral nervous systems and systemic circulation. AEs that occur usually can be managed and, in some cases, prevented. To mitigate risk, patients' histories should be reviewed to identify potential complicating factors (e.g., obesity or other risk factors for respiratory dysfunction in patients receiving IT morphine; a history of psychosis in patients receiving IT ziconotide). Also, treatment should be initiated at a low dose, titrated slowly, and patients should be closely monitored during treatment.

CONCLUSIONS

IT morphine and IT ziconotide are approved by the US Food and Drug Administration for patients who do not respond to less invasive treatments, but the safety profiles of each may make them more or less appropriate for certain patient populations.

Increased spasticity from a fracture in the baclofen catheter caused by Charcot spine: case report

In patients with Charcot spine, a loss of normal feedback response from the insensate spine results in spinal neuropathy. Increasing deformity, which can manifest as sitting imbalance, crepitus, or increased back pain, can result. We present the case of a patient with a high-thoracic spinal cord injury (SCI) who subsequently developed a Charcot joint at the T10-11 level that resulted in a dramatic increase in previously controlled spasticity after fracture of an existing baclofen catheter. The 68-year-old man with T4 paraplegia presented with increasing baclofen requirements and radiographic evidence of fracture of the intrathecal baclofen catheter with an associated Charcot joint with extensive bony destruction. The neuropathic spinal arthropathy caused mechanical baclofen catheter malfunction and resulting increased spasticity. The patient was found to have transected both his spinal cord and the baclofen catheter. Treatment consisted of removal of the catheter and stabilization with long-segment instrumentation and fusion from T6 to L2. Follow-up radiographs obtained a year and a half after surgery showed no evidence of hardware failure or significant malalignment. The patient has experienced resolution of symptoms and does not require oral or intrathecal baclofen. This is the only reported case of a Charcot spine causing intrathecal catheter fracture, leading to increased spasticity. This noteworthy case suggests that late spinal instability should be considered in the setting of SCI and increased spasticity.

Polyanalgesic Consensus Conference 2012: recommendations for the management of pain by intrathecal (intraspinal) drug delivery: report of an interdisciplinary expert panel

INTRODUCTION

The use of intrathecal (IT) infusion of analgesic medications to treat patients with chronic refractory pain has increased since its inception in the 1980s, and the need for clinical research in IT therapy is ongoing. The Polyanalgesic Consensus Conference (PACC) panel of experts convened in 2000, 2003, and 2007 to make recommendations on the rational use of IT analgesics based on preclinical and clinical literature and clinical experiences.

METHODS

The PACC panel convened again in 2011 to update the standard of care for IT therapies to reflect current knowledge gleaned from literature and clinical experience. A thorough literature search was performed, and information from this search was provided to panel members. Analysis of published literature was coupled with the clinical experience of panel members to form recommendations regarding the use of IT analgesics to treat chronic pain.

RESULTS

After a review of literature published from 2007 to 2011 and discussions of clinical experience, the panel created updated algorithms for the rational use of IT medications for the treatment of neuropathic pain and nociceptive pain.

CONCLUSIONS

The advent of new algorithmic tracks for neuropathic and nociceptive pain is an important step in improving patient care. The panel encourages continued research and development, including the development of new drugs, devices, and safety recommendations to improve the care of patients with chronic pain.

Catheter obstruction of intrathecal drug administration system -a case report-

Intrathecal drug administration system (ITDAS) can reduce the side effects while increasing the effectiveness of opioids compared to systemic opioid administration. Therefore, the use of ITDAS has increased in the management of cancer pain and chronic intractable pain. Catheter obstruction is a serious complication of ITDAS. Here, we present a case of catheter obstruction by a mass formed at the side hole and in the lumen. A 37-year-old man suffering from failed back surgery syndrome received an ITDAS implantation, and the ITDAS was refilled with morphine every 3 months. When the patient visited the hospital 18 months after ITDAS implantation for a refill, the amount of delivered morphine sulfate was much less than expected. Movement of the pump rotor was examined with fluoroscopy; however, it was normal. CSF aspiration through the catheter access port was impossible. When the intrathecal catheter was removed, we observed that the side hole and lumen of the catheter was plugged.

Role of pretrial systemic opioid requirements, intrathecal trial dose, and non-psychological factors as predictors of outcome for intrathecal pump therapy: one clinician's experience with lumbar postlaminectomy pain

OBJECTIVE

Non-psychological parameters may predict pump success.

METHODS

Review was performed on 35 implants for gender, age, pretrial/trial dose, baseline visual analog scale (VAS), and pain location. One-year outcomes were % change VAS/intrathecal dose and medication change. Spearman coefficients correlated pretrial/trial dose, age, baseline VAS, and % change in VAS/intrathecal dose. Wilcoxon Rank-Sum tests correlated gender/pain location and % change in VAS/intrathecal dose. Pretrial/trial dose, baseline VAS, and medication change was tested using Wilcoxon Rank-Sums. Chi-square was used to correlate medication change with gender/pain location. A two-sample t-test compared age and medication change.

RESULTS

Positive correlation between % change VAS and trial dose was noted. Greater age correlated with lower VAS and % dose change. Marginally significant difference in % dose change by pain location was present with higher doses for leg pain.

CONCLUSION

Trial dose, age, and partially pain location are good predictors of pain relief.

Can an intrathecal, catheter-tip-associated inflammatory mass reoccur?

OBJECTIVES

Intrathecal granuloma associated to the tip of catheters implanted in patients receiving long-term spinal infusion to alleviate chronic pain is a rare but potentially catastrophic complication. Its formation seems to be related to the intrathecal administration of opioid drugs, although not all opioids induce granuloma formation with the same frequency.

METHODS

In this clinical report, we describe an intrathecal granuloma that reoccur twice in the same patient after its surgical removal.

RESULTS AND DISCUSSION

This case report highlights the incomplete knowledge about the mechanism of granuloma formation and discuss the alternatives in the management of catheter-tip granulomas. This is the first case report of a patient in whom an intrathecal granuloma reoccurred twice after initial surgical removal. We also present and discuss a potential management strategy to avoid further surgery and resume intrathecal therapy early.

Intrathecal catheter granuloma associated with continuous sufentanil infusion

Intrathecal sufentanil is a minimally utilized opioid for patients with intractable pain refractory to traditional intrathecal medications. We present an 86-year-old female with a history of multiple spine surgeries who eventually progressed to having chronic, intractable, and diffuse low back pain. After failing medical management, she underwent a successful intrathecal trial of opioid therapy and was subsequently treated with an implantable drug delivery system (IDDS) or intrathecal pump. We describe the first reported case of formation of a catheter tip granuloma associated with intrathecal infusion of sufentanil. Due to increasing opioid requirements and gradually escalating pain, a computed tomography myelogram was performed to explore neuraxial etiologies of her symptoms. This investigation revealed the presence of a catheter tip-associated inflammatory mass (granuloma). All patients receiving intrathecal medications, including sufentanil, must be considered for the possibility of catheter-associated granuloma, particularly with symptoms of altered neurological function and/or increasing medication requirements associated with worsening pain.

Intrathecal ziconotide for neuropathic pain: a review

Neuropathic pain is a considerable burden that affects activities of daily living. The management of neuropathic pain can be challenging because of multiple etiologies and complex manifestations. Ziconotide is a nonopioid intrathecal (IT) analgesic option for patients with neuropathic pain refractory to conventional treatments. The objective of this article is to review the published literature on ziconotide for the treatment of neuropathic pain. Relevant publications were identified through searches of all years of 6 databases, which included PubMed, EMBASE, and CINAHL. Search terms used were ziconotide, SNX-111, MVIIA, Prialt, and neuropathic pain. Publications were included if ziconotide was intrathecally administered (either alone or in combination with other IT agents) to treat neuropathic pain of any etiology and if pain assessment was an outcome measure. Data extracted included study design, IT drug doses, pain outcome measures, and adverse events (AEs). Twenty-eight articles met the inclusion criteria: 5 were preclinical studies and 23 were clinical studies. In the preclinical studies, ziconotide demonstrated antiallodynic effects on neuropathic pain. Data from double-blind, placebo-controlled (DBPC) trials indicated that patients with neuropathic pain reported a mean percent improvement in pain score with ziconotide monotherapy that ranged from 15.7% to 31.6%. A low starting dose and slow titration of ziconotide resulted in an improved safety profile in the aforementioned trials. Common AEs associated with ziconotide include nausea and/or vomiting, dizziness, confusion, urinary retention, and somnolence. Evidence from DBPC trials, open-label studies, case series, and case studies suggests that ziconotide, as either monotherapy or in combination with other IT drugs, is a potential therapeutic option for patients with refractory neuropathic pain. Additional studies are needed to establish the long-term efficacy and safety of ziconotide for neuropathic pain.

[Spinal granuloma in a patient receiving a spinal infusion of morphine and clonidine]

Patients treated with long-term spinal infusion of high doses of morphine develop a granuloma at the location of the catheter tip. Diagnosis is based on a steady increase in intrathecal morphine dosage after a relatively prolonged period of stability, on the gradual development of neurologic signs and symptoms suggesting radicular or spinal cord compression, and on magnetic resonance images. We describe a man with central neuropathic pain after removal of a tumor. The presence of all 3 of the aforementioned diagnostic criteria led to suspicion of a spinal granuloma.