Computed tomography-guided transforaminal lumbar puncture using local anesthesia and a straight 22-gauge spinal needle for intrathecal nusinersen in adults: Findings in 77 procedures.

BACKGROUND: Intrathecal nusinersen is the first Food and Drug Administration-approved treatment for spinal muscular atrophy. Reliable intrathecal access is critical for initial and maintenance therapy; however, this can be challenging in older patients with spinal muscular atrophy many of whom have had prior lumbar instrumentation and osseous fusion. Transforaminal lumbar punctures have emerged as a technique for intrathecal access that avoids the hazards of cervical punctures. We describe our technique for transforaminal lumbar punctures under computed tomography guidance using local anesthesia and a straight 22-gauge needle. METHODS: Following local institutional review board approval, medical records of all patients undergoing computed tomography-guided transforaminal lumbar puncture for intrathecal nusinersen injection were obtained and analyzed. The rate of technical success and immediate complications were recorded. Any delayed complications noted in a 3-day follow-up phone call and future office visit were also recorded. Data collation and analysis were performed using Excel. RESULTS: A total of 77 transforaminal lumbar punctures were performed with intrathecal administration of nusinersen, for a 100% technical success rate. Local anesthesia was used in 76 cases, with conscious sedation used in one case. General anesthesia was not used in any case. There were no major complications. One patient had a postdural puncture headache that resolved completely after a transforaminal epidural blood patch performed 4 days later. CONCLUSIONS: Intrathecal administration of nusinersen is critical for treatment of patients with spinal muscular atrophy. Our described technique allows for reliable access to the intrathecal space using local anesthesia and a straight 22-gauge spinal needle under computed tomography guidance, and is easily reproducible.

JOURNAL CLUB: Longitudinal Qualitative Characterization of MRI Features After Laser Interstitial Thermal Therapy in Drug-Resistant Epilepsy.

OBJECTIVE: Laser interstitial thermal therapy (LITT), a method for ablating brain tissue under real-time MR thermometry, has been used more frequently in recent years to treat nonmalignant lesions. The purpose of this study is to longitudinally characterize MRI features after LITT in patients with drug-resistant epilepsy, primarily in the setting of mesial temporal sclerosis. MATERIALS AND METHODS: MR images from 23 consecutive patients who underwent LITT were retrospectively reviewed. All patients had images obtained immediately after the ablation. Multiple patients had follow-up imaging at various time points after treatment, from postoperative days 7 through 1539. A total of 54 MRI studies were reviewed. RESULTS: Immediately after LITT, MR images showed a ring-enhancing lesion at the ablation site with minimal surrounding edema. Seven images showed increased enhancement of the ipsilateral choroid plexus. Images in the subacute phase showed a mild increase in edema with similar enhancement. Images in the transitional phase showed a decrease in edema with variable enhancement. Images in the chronic phase showed minimal gliosis with or without cavity formation or cavity formation alone, with either decreased or no enhancement. CONCLUSION: This report describes the time course of the imaging findings after LITT for drug-resistant epilepsy. The typical stages include rim-enhancing lesion with minimal edema, followed by an increase in edema, to eventual gliosis and nonenhancing cavity formation. Radiologists need to be familiar with the postablation findings to minimize misdiagnosis and prevent unnecessary workup.