3:36 PM Abstract No. 350 Intrathecal catheter and port placement for nusinersen infusion in patients with spinal muscular atrophy and spinal fusion: Technical note

Abstract

Spinal muscular atrophy (SMA) is among the most common monogenic causes of spinal motor neuron(SMN) degeneration with severely affected cases having a median survival of less than 2 years of age. Nusinersen (Spinraza) is a novel antisense oligonucleotide administered intrathecally for treatment of SMA. Most of these patients have scoliosis often treated by posterior fusion from T2 to sacrum making lumbar puncture challenging. Building on our prior experience in intrathecal catheter placement, we describe our initial experience with an image-guided approach to implantation of intrathecal catheters and subcutaneous ports in patients with SMA with extensive spinal fusions. IRB-approved retrospective study included 12 patients who underwent intrathecal catheter and port placement from June 2018 to April 2019. Intrathecal access was obtained by an interventional radiologist utilizing iGuide software and Dyna CT. A 14G bone penetration set was used to drill an osseous tunnel through the spinal fusion mass and using Touhy needle, a 3.7 Fr intrathecal catheter was advanced into cervical subarachnoid space. A subcutaneous port was then placed by a neurosurgeon and connected to the intrathecal catheter. Port patency was confirmed by contrast injection. Patient demographics and procedure demographics (table) were collected and analyzed. The Study included 4 males and 8 females, all with spinal fusion. Average radiation dose was 857 mGy, exposure time was 3.3 min to 12 min, EBL was 8.33 mL and mean total procedure time was 1:54 hr. The procedure was technically successful in all cases with no immediate postprocedural complications. 2 patients developed delayed CSF leak which was treated with epidural blood patch successfully. In 2 patients, CSF could not be aspirated prior to drug injection however catheter patency was confirmed by contrast injection study. Our novel technique is safe, effective, negates the requirement for open surgery to gain intrathecal access, and reduces cumulative radiation exposure incurred during repeated fluoroscopy-guided lumbar punctures. Despite initial success, more extensive prospective study to determine the long-term outcome of this novel technique is needed.Tabled 1Procedure DemographicsPatient NumberAccessTip of CatheterRadiation Dose (mGy)Radiation Time (mins)EBL (mL)Total Time (hh:mm)1L3-L4T5-612555.7101:562L3-L4T413477101:533L3-L4T18809101:554L3-L4T1387552:045L3-L4T1447552:076L3-L4T1111111.451:547L3-L4T44955.151:498L4-L5T5-T6136812101:459L3-L4C75553.3201:3210L3-L4T17397.952:1411L4-L5T183110.9101:3512L3-L4T18698.4102:01 Open table in a new tab