Relationship between compression time and long-term hypoesthesia in primary trigeminal neuralgia treated with percutaneous balloon compression.

Percutaneous balloon compression is a surgical method for the treatment of trigeminal neuralgia, but one of the surgical parameters, compression time, is inconclusive. To investigate the effect of compression time during balloon compression on long-term postoperative hypoesthesia in patients with primary trigeminal neuralgia and to provide guidance on relevant parameters for balloon compression in the treatment of primary trigeminal neuralgia, we conducted a nested case-control study. Patients with primary trigeminal neuralgia treated by balloon compression from March 2013 to September 2013 were divided into case group and control group according to whether there were still symptoms of hypoesthesia at present. The relationship between the compression time of balloon compression and long-term hypoesthesia was analyzed. A total of 289 trigeminal neuralgia patients treated with percutaneous balloon compression were included in this study. Multivariate logistic regression showed that compression time was significantly correlated with long-term hypoesthesia (OR = 1.91, 95% CI = 1.13-3.23, P = 0.02), and compression time was greater than one. The risk of hypoesthesia in the long-term when the compression time is longer than 1 min is 1.93 times that of 1 min. PBC is a safe and effective surgical method, and the long-term hypoesthesia is related to the compression time during operation. The longer the compression time during operation, the greater the risk of long-term hypoesthesia.

The Effect of Depth of Anesthesia on Hemodynamic Changes Induced by Therapeutic Compression of the Trigeminal Ganglion.

BACKGROUND: Percutaneous compression of the trigeminal ganglion (PCTG) has been used to treat trigeminal neuralgia since 1983. A PCTG-related trigeminocardiac reflex (TCR) can induce dramatic hemodynamic disturbances. This study investigates the effects of depth of propofol anesthesia on hemodynamic changes during PCTG. MATERIALS AND METHODS: A total of 120 patients who underwent PTCG for trigeminal neuralgia were randomly assigned to control group-intravenous saline pretreatment before PCTG puncture and anesthesia targeted to bispectral index (BIS) 40 to 60 throughout, and study group-intravenous propofol 1 to 2 mg/kg pretreatment to deepen anesthesia to BIS<40 before PCTG. Mean arterial pressure, heart rate (HR), cardiac output, system vascular resistance, and BIS were measured at 9 time points during the procedure, and the incidence of the TCR was observed at T5 and T6. RESULTS: BIS was lower in the study group compared with the control after pretreatment with propofol or saline, respectively. Compared with the control group, mean arterial pressure was lower in the study group at several points during the procedure, but there was no difference in HR between the 2 groups at any point. Cardiac output was higher and system vascular resistance lower in the study compared with the control group. In the control group, 42 (70.0%) and 52 (86.7%) of patients developed a TCR at the 2 points, and 37 (67.1%) and 45 (75.0%) in the study group. There was no difference in the incidence of TCR between the 2 groups. CONCLUSION: Increasing the depth of propofol anesthesia partially attenuated PTCG-related elevation of blood pressure but did not modify the abrupt reduction in HR.

Clinical classification of clival chordomas for transnasal approaches.

Endoscopic endonasal approaches (EEAs) are ideal for most chordomas, but there is little information regarding the practical clinical classification of clival chordomas to guide surgery with EEAs. This article investigates a relatively concise and practical clinical classification system for clival chordomas and summarizes the clinical characteristics and operative key points of different clinical types. Here, 55 patients with clival chordomas treated through EEAs from 2012 to 2017 were retrospectively reviewed. Depending on the origin of the notochord and the growth pattern of the tumor, with our introduced Wang's line, these cases of clival chordoma were divided into types I-IV. There were 14 cases of type I-A, 7 cases of type I-B, 10 cases of type II, 10 cases of type III-A, 7 cases of type III-B, and 7 cases of type IV. The gross total resection (GTR) rate of primary and recurrent type I tumors was 64% and 25%, and residual tumors were found mainly in cases with involvement of the cavernous sinus or the posterior upper part of the dorsum sella. The GTR rate of primary and recurrent type II tumors was 85% and 66.6%, respectively. Residual tumors were found in cases with involvement of the petrous apex. The GTR rate of primary and recurrent type III tumors was 75% and 20%, and residual tumors were found in cases with involvement of the parapharyngeal space and dorsal side of C1-2. Residual type I-B and type III-B tumors were found when there was BA or VA adhesion or brain stem invasion. Our new classification method proposed here can be used to guide the resection of clival chordomas through EEAs.

Endovascular Treatment of Rare Vascular Complications of Percutaneous Balloon Compression for Trigeminal Neuralgia.

AIM: To present the clinical features and outcomes of rare vascular complications of percutaneous balloon compression (PBC) for trigeminal neuralgia. These complications were treated by the endovascular technique. MATERIAL AND METHODS: In this retrospective study, 5 patients with trigeminal neuralgia were treated by PBC, who complicated vascular incidence between December 2000 and May 2011. The complications included 3 internal carotid cavernous fistulae (CCF) and 2 external carotid artery system fistulae. These complications were treated by endovascular coil embolism and balloon occlusion techniques. RESULTS: Five patients (100%) had pain free after the PBC. All the complications were cured and symptoms were gradually improved. There was no recurrence of trigeminal neuralgia or vascular complication symptoms during the follow-up period (mean 20 months, range 7-52 months). CONCLUSION: Endovascular treatment is effective and safe for the rare iatrogenic vascular complications of the PBC procedure. Neurosurgeons should be made aware of this complication. Timely diagnosis and expedient treatment should be ensured as early as possible in order to decrease further danger.

Neurosurgical treatment of glossopharyngeal neuralgia: analysis of 103 cases.

OBJECTIVE: The object of this study was to investigate the immediate and long-term follow-up results of glossopharyngeal nerve rhizotomy (GPNR) with or without partial vagus nerve rhizotomy (VNR) for treating glossopharyngeal neuralgia (GPN). METHODS: A retrospective review of the case notes of patients who had undergone surgery for GPN in the authors' department between 2008 and 2013 was performed to investigate baseline characteristics and immediate outcomes during the hospitalization. For the long-term results, a telephone survey was performed, and information on pain recurrence and permanent complications was collected. Pain relief meant no pain or medication, any pain persisting after surgery was considered to be treatment failure, and any pain returning during the follow-up period was considered to be pain recurrence. For comparative study, the patients were divided into 2 cohorts, that is, patients treated with GPNR alone and those treated with GPNR+VNR. RESULTS: One hundred three procedures, consisting of GPNR alone in 38 cases and GPNR+VNR in 65 cases, were performed in 103 consecutive patients with GPN. Seventy-nine of the 103 patients could be contacted for the follow-up study, with a mean follow-up duration of 2.73 years (range 1 month-5.75 years). While there were similar results (GPNR vs GPNR+VNR) in immediate pain relief rates (94.7% vs 93.8%), immediate complication rates (7.9% vs 4.6%), and long-term pain relief rates (92.3% vs 94.3%) between the 2 cohorts, a great difference was seen in long-term complications (3.8% vs 35.8%). The long-term complication rate for the combined GPNR+VNR cohort was 9.4 times higher than that in the GPNR cohort. There was no operative or perioperative mortality. Immediate complications occurred in 6 cases, consisting of poor wound healing in 3 cases, and CSF leakage, hoarseness, and dystaxia in 1 case each. Permanent complications occurred in 20 patients (25.3%) and included cough while drinking in 10 patients, pharyngeal discomfort in 8 patients, and hoarseness and dysphagia in 1 case each. CONCLUSIONS: In general, this study indicates that GPNR alone or in combination with VNR is a safe, simple, and effective treatment option for GPN. It may be especially valuable for patients who are not suitable for the microvascular decompression (MVD) procedure and for surgeons who have little experience with MVD. Of note, this study renews the significance of GPNR alone, which, the authors believe, is at least valuable for a subgroup of GPN patients, with significantly fewer long-term complications than those for rhizotomy for both glossopharyngeal nerve and rootlets of the vagus nerve.

Micro-surgical decompression for greater occipital neuralgia.

AIM: To evaluate the clinical effect of micro-surgical decompression of greater occipital nerve for greater occipital neuralgia (GON). MATERIAL AND METHODS: 76 patients underwent surgical decompression of the great occipital nerve. A nerve block was tested before operation. The headache rapidly resolved after infiltration of 1% Lidocaine near the tender area of the nerve trunk. RESULTS: 89 procedures were performed for 76 patients. The mean follow up duration was 20 months (range 7-52 months). The headache symptoms of 68 (89.5%) patients were completely resolved, and another 5 (6.6%) patients were significantly relieved without the need for any further medical treatment. Three (3.9%) patients experienced recurrence of the disorder. All patients experienced hypoesthesia of the innervated area of the great occipital nerve. They recovered gradually within 1 to 6 months after surgery. CONCLUSION: Micro-surgical decompression of the greater occipital nerve is a safe and effective method for greater occipital neuralgia. We believe our findings support the notion that the technique should also be considered as the first-line procedure for GON.

A support vector machine-recursive feature elimination feature selection method based on artificial contrast variables and mutual information.

Filtering the discriminative metabolites from high dimension metabolome data is very important in metabolomics study. Support vector machine-recursive feature elimination (SVM-RFE) is an efficient feature selection technique and has shown promising applications in the analysis of the metabolome data. SVM-RFE measures the weights of the features according to the support vectors, noise and non-informative variables in the high dimension data may affect the hyper-plane of the SVM learning model. Hence we proposed a mutual information (MI)-SVM-RFE method which filters out noise and non-informative variables by means of artificial variables and MI, then conducts SVM-RFE to select the most discriminative features. A serum metabolomics data set from patients with chronic hepatitis B, cirrhosis and hepatocellular carcinoma analyzed by liquid chromatography-mass spectrometry (LC-MS) was used to demonstrate the validation of our method. An accuracy of 74.33±2.98% to distinguish among three liver diseases was obtained, better than 72.00±4.15% from the original SVM-RFE. Thirty-four ion features were defined to distinguish among the control and 3 liver diseases, 17 of them were identified.

Serum metabolomics reveals the deregulation of fatty acids metabolism in hepatocellular carcinoma and chronic liver diseases.

Patients with chronic liver diseases (CLD) including chronic hepatitis B and hepatic cirrhosis (CIR) are the major high-risk population of hepatocellular carcinoma (HCC). The differential diagnosis between CLD and HCC is a challenge. This work aims to study the related metabolic deregulations in HCC and CLD to promote the discovery of the differential metabolites for distinguishing the different liver diseases. Serum metabolic profiling analysis from patients with CLD and HCC was performed using a liquid chromatography-mass spectrometry system. The acquired large amount of metabolic information was processed with the random forest-recursive feature elimination method to discover important metabolic changes. It was found that long-chain acylcarnitines accumulated, whereas free carnitine, medium and short-chain acylcarnitines decreased with the severity of the non-malignant liver diseases, accompanied with corresponding alterations of enzyme activities. However, the general changing extent was smaller in HCC than in CIR, possibly due to the special energy-consumption mechanism of tumor cells. These observations may help to understand the mechanism of HCC occurrence and progression on the metabolic level and provide information for the identification of early and differential metabolic markers for HCC.

A random forest of combined features in the classification of cut tobacco based on gas chromatography fingerprinting.

We applied the random forest method to discriminate among different kinds of cut tobacco. To overcome the influence of the descending resolution caused by column pollution and the subsequent deterioration of column efficacy at different testing times, we constructed combined peaks by summing the peaks over a specific elution time interval Deltat. On constructing tree classifiers, both the original peaks and the combined peaks were considered. A data set of 75 samples from three grades of the same tobacco brand was used to evaluate our method. Two parameters of the random forest were optimized using out-of-bag error, and the relationship between Deltat and classification rate was investigated. Experiments show that partial least squares discriminant analysis was not suitable because of the overfitting, and the random forest with the combined features performed more accurately than Naïve Bayes, support vector machines, bootstrap aggregating and the random forest using only its original features.

Expression, purification and characterization of recombinant human beta-amyloid 1-42 in Pichia pastoris.

The human peptide rhA beta(1-42) was effectively produced through a novel expression system and purification procedure. The peptide rhA beta(1-42) was successfully expressed in Pichia pastoris, the methylotrophic yeast that has never been used as host. The cDNA encoding full-length hA beta(1-42) was synthesized with yeast bias codons and cloned into the pPICZ alpha A vector in frame with the yeast alpha-factor secretion signal under the transcriptional control of the AOX1 promoter and integrated into the secreting expression organism P. pastoris strain X33. Production of rhA beta(1-42) through fermentation was further optimized and scaled up in an 80 L fermentor. Secreted rhA beta(1-42) was purified using a two-step purification scheme: SP Sepharose ion exchange chromatography and source 30 RPC. The purification procedure is fast and efficient and reached a recovery of >93% without loss of activity. The purified rhA beta(1-42) was confirmed by Western blotting analysis and N-terminals amino sequencing analysis. This efficient and cost-effective expression system facilitates large-scale production and purification for recombinant rhA beta(1-42).