Background: Botulinum toxin type A is an effective treatment for trigeminal neuralgia. Moreover, its efficacy in type 2 trigeminal neuralgia and comparative studies between type 1 and type 2 trigeminal neuralgia (TN) still need to be improved. Methods: We treated 40 TN patients with onabotulinumtoxinA; 18 had type 1 TN, and 22 had type 2 TN. We compared the baseline pain score with the Visual Analogue Scale (VAS) and paroxysm frequency (number per week) at the baseline with those obtained at 1-month and 3-month follow-ups. Nonetheless, we compared the baseline Penn Facial Pain Scale with the scores obtained at the 1-month follow-up. Results: BoNT/A effectively reduced pain intensity and frequency at the 1-month and 3-month follow-ups. Moreover, the type 1 TN and type 2 TN groups had baseline pain scores of 7.8 ± 1.65 and 8.4 ± 1.1, respectively. Pain significantly improved (p < 0.001) in both groups to 3.1 ± 2.3 (type 1 TN) and 3.5 ± 2.3 (type 2 TN) at the 1-month follow-up and to 3.2 ± 2.5 (type 1 TN) and 3.6 ± 2.5 (type 2 TN) at the 3-month follow-up. There was no difference between the two groups (p 0.345). The baseline paroxysm frequencies (number per week) were 86.7 ± 69.3 and 88.9 ± 62.2 for the type 1 and type 2 TN groups, respectively; they were significantly reduced in both groups at the 1-month and 3-month follow-ups without significant differences between the two groups (p 0.902). The Pain Facial Pain Scale improved at the 1-month follow-up, and no significant differences were found between the two groups. There was a strong correlation between background pain and paroxysm pain intensity (r 0.8, p < 0.001). Conclusions: Botulinum toxin type A effectively reduced the pain, paroxysm frequency, and PFPS scores of type 1 and type 2 trigeminal neuralgia patients without statistically significant differences. Facial asymmetry was the only adverse event.

We treated a 51-year-old woman with refractory Complex Regional Pain Syndrome type I (CRPS-I) involving her left hand and forearm with subcutaneous injections of BoNT/A. The injections were performed every 3 months, with a total of six treatments. Each treatment was able to effectively improve pain and motor impairment; however, the duration of the effect was limited to only a few months. BoNT/A could improve patients’ quality of life with CRPS; however, extensive clinical studies are needed to determine its role in clinical practice.

Essential blepharospasm (BEB) is a focal dystonia characterized by abnormal brainstem excitability and impaired inhibitory control within trigeminal–facial circuits. Botulinum toxin type A (BoNT-A) is the established first-line treatment, primarily acting at the neuromuscular junction. However, whether BoNT-A also modulates central brainstem circuits in BEB patients remains unclear, and dedicated neurophysiological studies have yielded conflicting results. To investigate whether BoNT-A modulates brainstem interneuronal excitability in BEB using the blink reflex recovery cycle and to correlate clinical outcomes with neurophysiological results. Thirteen patients with BEB underwent neurophysiological and clinical evaluation before (T0) and one month after (T1) BoNT-A treatment. The blink reflex recovery cycle was assessed at interstimulus intervals (ISIs) of 200, 300, 500, and 1000 ms. Clinical severity was assessed using the BSPSS, JRS, and BDS scales. The R2 amplitude ratio showed a statistically significant decrease after treatment across all ISIs (all p ≤ 0.001), indicating reduced brainstem interneuronal excitability. All clinical scales demonstrated statistically significant improvement after treatment (BSPSS, JRS, BDS; all p < 0.001). This pilot study provides preliminary evidence that BoNT-A treatment may reduce brainstem interneuronal excitability in BEB patients, as evidenced by a substantial and consistent decrease in R2 amplitude ratios of the blink reflex recovery cycle. These findings are consistent with a central modulatory effect of BoNT-A beyond its established peripheral action. Larger controlled studies are warranted to confirm these results.