Journal de neurologie clinique et de neurochirurgie

• Why the cranial parasympathetic ganglions are going with the Trigeminal nerve branches (V1, V2, V3)?

• Why the lacrimal organ gets secretomotor filaments from pterygopalatine ganglion which is situated in pterygopalatine fossa by means of zygomatic part of V2 to lacrimal nerve of V1 and not get such strands from the neighboring ciliary ganglion?

Background: Chronic back and leg pain is a leading cause of disability and results in a significant health care expenditure. Options such as physical therapy, corticosteroids Epidural Injections (ESI) or spine surgery have limited long term benefit and may cause significant morbidity. Clonidine has anti-neuropathic pain and anti-inflammatory properties. A novel, slow-release biodegradable polymer (Poly (D, L-lactide) clonidine micropellets deliver sustained, high clonidine levels and may provide prolonged pain relief with minimal systemic side effects. Methods: A pilot multicenter investigation of the safety, pharmacokinetics (PK) and effectiveness of clonidine micropellets in patients with chronic lumbosacral radiculopathy. Three sequential cohorts of 18 subjects each received a single epidural injection of clonidine 0.325 mg, 0.975 mg or 1.95 mg (1, 3 or 6 micropellets, respectively) at the interlaminar epidural level that corresponds to the painful dermatomes. Clonidine PK was evaluated at multiple time points for 84 days. Paired t-tests were performed to examine changes from baseline within each cohort, and analysis of covariance evaluated differences between dose levels. NRS and RMS-Q disability scores were recorded at baseline and for one year follow up. Results: Peak plasma clonidine was observed 24h after injection and the mean elimination half-life ranged from 13 to 20 days. Statistically significant reduction in leg and back pain from baseline at all-time points up to 1 year was observed, in all cohorts as well as significant improvement in the RMS-Q at all timepoints. Adverse events and rescue medications were also recorded. Conclusion: Clonidine Micropellets would safely and slowly deliver clonidine over a prolonged period. Clonidine’s anti-neuropathic and anti-inflammatory effects could treat the radicular back and leg pain.