Somatosensory and trigeminal pathway abnormalities in Chinese patients with trigeminal neuralgia.

This study aimed to evaluate somatosensory function in Chinese patients with trigeminal neuralgia (TN) using a standard quantitative sensory testing (QST) battery and electrophysiological tests consisting of contact heat-evoked potentials (CHEPs) and blink reflex (BR). Twenty patients with TN and 20 sex- and age-matched healthy controls were recruited for this study. A standard QST protocol recommended by the German Research Network on Neuropathic Pain was carried out on the patients' painful and contralateral faces, the controls' right faces, and all participants' right hands. The CHEPs and BR were recorded at the Cz electrode and bilateral lower bellies of the orbicularis oculi, respectively, with thermal stimuli applied to both sides of the patient's face and the control's right face. The cold detection threshold, heat pain threshold, and mechanical pain threshold on the painful face were lower than those of healthy controls (P < 0.05), whereas the cold pain threshold and mechanical detection threshold were higher (P < 0.05) on the painful faces than those of the contralateral faces from patients or healthy controls. Mechanical pain sensitivity was higher in both test sites than in healthy controls (P < 0.05). Significantly longer N latencies (P < 0.05) and lower N-P amplitudes (P < 0.01) were detected in the patients' painful sites than in the contralateral sites and those of healthy controls. Comprehensive somatosensory abnormalities were found in painful facial sites in patients with TN, suggesting disturbances in the processing of somatosensory stimuli. Deficiencies in electrophysiological tests further revealed unilaterally impaired function of the trigeminal pathway in TN patients.

Use of sensory and motor action potentials to identify the position of trigeminal nerve divisions for radiofrequency thermocoagulation.

OBJECT: The objective of this study was to develop an electrophysiological method for intraoperative localization of the trigeminal nerve branches during radiofrequency thermocoagulation (RFTC). METHODS: Twenty-three patients who were scheduled to undergo RFTC were included. The trigeminal nerve root was stimulated through the foramen ovale using the radiofrequency cannula. Antidromic responses were recorded from the target division through supraorbital, infraorbital, and mental foramina electrodes, and an additional electrode at the masseter muscle. Sensory and motor action responses, as well as verbal and masseter contraction responses, were recorded and correlated. RESULTS: The antidromic responses were easily recorded in the target division in all 23 patients, and they were invariably correlated with the patient's verbal responses. The potentials were recorded successively from V1 to V3. The amplitude in each division before and after RFTC showed little difference in response to electrical stimulation with the same current. The motor trigeminal nerve action potentials were recorded in 10 patients; 7 of these patients had postoperative masseter muscle weakness, while the remaining 3 had normal masseter muscle function. Potentials with low amplitudes were usually obtained from neighboring divisions, but no unexpected denervation of any branches was observed. All the patients experienced immediate pain relief after the procedure. CONCLUSIONS: This technique is sensitive and easy to apply. The sensory and motor potentials matched the verbal responses and the complications. Although it cannot completely substitute for the patient's verbal response, this approach is helpful in uncooperative patients, and it predicts and reduces the incidence of masseter muscle weakness. The use of these complementary techniques could increase the chances of treatment success.

[Controlled clinical study of trigeminal ganglion puncture guided by CT/MRI image fusion interface navigation].

OBJECTIVE: To build the radio-frequency thermocoagulation (RFT) interface under navigation including foramen ovale and trigeminal ganglion based on CT/MRI image fusion technology, to visualize the relationship between the trigeminal ganglion and the puncture needle, and to observe clinical effects of this method. METHODS: CT and MRI data of 20 trigeminal neuralgia patients which were input into BrainLAB-iPlan navigation planning system, were aligned and merged, so that the 3-dimentional image fusion interface of CT and MRI for puncture was built. According to the image fusion interface, the pathways targeting the trigeminal ganglion were planned to assist trigeminal ganglion puncture and RFT. The treatment consequences were observed and compared with 20 patients under the RFT only with the direction of pre- and intra-operative CT. RESULTS: In the group of CT/MRI image fusion cases, 3 cases had been predicted to be difficult because of unreachable ganglion through the foramen ovale pathway. The postoperative clinical examination proved that the ganglions of these 3 cases were only insufficiently damaged or undamaged. The other 17 cases proved better results, except 2 cases whose treatment was changed in operation. The valid rates for both image fusion navigation group and CT group were all above 95%. CONCLUSION: Navigation interface including both foramen ovale and trigeminal ganglion based on CT/MRI image fusion made visualization of the pathway targeting ganglion come true, which made the treatment more accurate and individual. Whether the pathway could reach the ganglion might distinguish the trouble cases from others.

Ultrasound promoted one-pot synthesis of 3-aza-6,10-diaryl-2-oxa-spiro[4.5]decane-1,4,8-trione.

One-pot synthesis of 3-aza-6,10-diaryl-2-oxa-spiro[4.5]decane-1,4,8-trione from 1,5-diaryl-1,4-pentadien-3-one can be carried out in good yields at 50 degrees C under ultrasound irradiation. This method provided several advantages such as simple work-up procedure, shorter reaction time and higher yield.

One-pot synthesis of benzylacetamide from oxime under ultrasound irradiation.

One-pot synthesis of benzylacetamide from oxime can be carried out in 80-95% yield at 35-40 degrees C under ultrasound irradiation. This method provided several advantages such as simple work-up procedure, shorter reaction time and higher yield.