Do bubbles matter amid PBC for trigeminal neuralgia?

BACKGROUND: As a simple and safe alternative intervention, percutaneous balloon compression (PBC) has been gradually adopted by a growing number of neurosurgeons to treat trigeminal neuralgia. A pear-shaped opacity observed fluoroscopically, which indicates full suffusion of Meckel's cave conducting sufficient pressure against Gasserian ganglion, is believed to be the key to its success. Sometimes, a bitten pear may appear due to bubbles in the balloon but is usually ignored. OBJECTIVE: This study aims to investigate the effects of the bubbles on postoperative outcomes. METHODS: Patient data were obtained from the consecutive cases undergoing PBCs in our department between 2019 and 2021. Among them, pain and numbness were used to assess the efficacy of PBC based on Barrow Neurology Institute (BNI) scoring system. It was defined as an effective outcome if the postoperative pain intensity grade was lower than II. And those with numbness grade > II were regarded as numb incidence. RESULTS: We eventually recruited 59 cases, including 42 in full pear and 17 in bitten pear groups with follow-up time up to 44 months. The early effective rates were 95.2% and 82.4%, respectively (p > 0.05), which turned to 88.1% and 52.9% during the last follow-up period (p < 0.01). This result indicated that the bitten pear gave rise to a significantly higher recurrence. In terms of numbness, there was no significant difference. CONCLUSION: Gas does not yield enough pressure as liquid, and cannot exert enough pressure to the semilunar ganglion. Therefore, air evacuation should not be ignored before injection.

Riveting technique in percutaneous balloon compression for trigeminal neuralgia remedy.

BACKGROUND: The percutaneous balloon compression (PBC) is a safe and simple treatment for trigeminal neuralgia. It works by compressing the Gasserian ganglion to block pain signals from the trigeminal nerve. To ensure effectiveness, it is important to focus the compression on the lower part of the balloon. OBJECTIVE: To validate the efficacy of a riveting technique, specifically pulling an inflated balloon, in order to apply enhanced compression on the ganglion. METHODS: To compare this novel technique with the conventional approach, a retrospective investigation was conducted on consecutive PBCs performed in our department between 2019 and 2022. For postoperative outcome assessment, efficacy was defined as achieving a VAS score of 0 or an improvement exceeding 5 points. Postoperative numbness was graded as none, mild, or severe based on its impact on daily life and tolerance level. RESULTS: Excluding cases with missed follow-up, a total of 179 participants were included in the study, and their follow-up period ranged up to 40 months. Postoperatively, symptomatic remission was achieved by 98.1% (52/53) of patients in the riveting technique group compared to 87.3% (110/126) in the conventional group (P<0.05). At the last follow-up period, with recurrence observed over time, the long-term efficacy of riveting and conventional groups were 94.3% and 74.6%, respectively (P<0.05). The majority of cases in both groups experienced ipsilateral facial numbness immediately following PBC, which appeared to diminish after 3 months in both groups without significant difference between them (P>0.05).

Lumbar Endoscopic Unilateral Laminotomy With Bilateral Decompression Surgery in Severe Lumbar Stenosis Under Electrophysiological Monitoring-Focused on Full-Visualized Trephine/Osteotome.

OBJECTIVE: Although endoscopic drill has the advantages in manipulation and hemostasis, whose low efficiency and blurred vision reduce the efficacy of lumbar endoscopic unilateral laminotomy with bilateral decompression (LE-ULBD). The present study was designed to evaluate the safety and efficacy of full-visualized trephine/osteotome in the LE-ULBD surgery for severe lumbar stenosis. METHODS: Fifty-seven severe lumbar stenosis patients who underwent LE-ULBD between January 2020 to January 2023 were enrolled, who were divided into drill and visualized trephine groups. The medical records including demographics, operative duration, intraoperative electrophysiological findings, postoperative hospital stay or hospital stay, postoperative outcomes and complications were retrospectively reviewed and analyzed. RESULTS: A total of 57 patients included 15 in drill and 42 in trephine group were enrolled in the study. There was significant difference in the pre- and postoperative visual analogue scale and Oswestry Disability Index scores in both groups (p < 0.05). The mean operative duration in the trephine group (101.05 ± 12.18 minutes) was shorter than that in the drill group (134.67 ± 9.68 minutes) (p < 0.05). There was no statistical difference between the 2 groups in electrophysiological monitoring, posthospital stays, postoperative outcomes and complications. Abnormal free-electromyography (EMG) were recorded in 2 (13.3%) and 5 patients (11.9%) in the drill and trephine group. Intraoperative somatosensory evoked potential changes occurred in 3 (20%) and 3 patients (7.1%) in the drill and trephine group and all patients recovered immediately when surgery ended. No serious complications and recurrence occurred in all the patients. CONCLUSION: Full-visualized trephine/osteotome has been approved to be convenient, safe and efficient in our study, which combined with translaminar inside-out technique and EMG monitoring especially free-EMG may offer a new choice in LE-ULBD surgery for lumbar stenosis patients.

The Value of a Headless Pear Shape in Percutaneous Balloon Compression for Trigeminal Neuralgia.

BACKGROUND AND OBJECTIVES: Percutaneous balloon compression (PBC) has been regarded as a simple and effective remedy for trigeminal neuralgia. This study aims to retrospectively analyze the correlation between intraoperative balloon shapes and postoperative outcomes. METHOD: Those consecutive PBC cases performed in our department between 2019 and 2022 were reviewed. According to the intraoperative balloon figures, they were cataloged as headless pear, slim pear, bottle gourd, and winter melon groups. The degree of pain or numbness was quantified using the visual analog scale. Those pain-free or pain score <3 and satisfied by the patient were called effective, and those numb score >3 were taken into account of numbness incidence. RESULTS: Except for missing cases, 160 were finally recruited in this study with a mean follow-up for 23.6 ± 12.8 months. Postoperatively, the pain score plunged from 8.8 ± 1.0 to 0.8 ± 2.0 immediately, which rose slightly over time and maintained at 2.4 ± 3.1. The maximal pain score drop occurred in the headless pear group ( P < .001) and the minimal in the winter melon group ( P < .001). The early efficacy of PBC was 100%, 84.1%, 91.4%, and 50.0%, respectively. However, the long-term efficacy was 88.2%, 75.0%, 82.1% and 25.0%. The ipsilateral numbness occurred in most of the cases immediately after PBC with a score of 3.5 ± 2.3, which decreased significantly within 3 months to 2.3 ± 2.0 and turned to 1.7 ± 1.8 finally ( P < .05). The highest and lowest numb score appeared in bottle gourd and winter melon groups, respectively ( P < .05). CONCLUSION: A headless pear shape emerged in lateral fluoroscopy as the balloon was fully inflated indicates that the entire Meckel cave is suffused, and hence, the anterior semilunar ganglion has been solidly compressed, which may lead to a successful outcome.

A Comparative Review of the Outcome Following MVD and PBC in Patients with Trigeminal Neuralgia.

BACKGROUND: This study aims to systematically review the treatment outcomes of percutaneous balloon compression (PBC) and microvascular decompression (MVD) in patients with trigeminal neuralgia. METHODS: A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline was performed using PubMed, Embase, and Cochrane Central Registry of Controlled Trials databases. Only those articles with more than 5 years' follow-up length were included in this investigation. To uniformly assess the postoperative outcome, we defined pain relief as totally pain free, while the postoperative hospitalization and last follow-up period were defined as early and long term, respectively. The facial numbness was quantified with Barrow Neurological Institute Pain Intensity Score (BNI). RESULTS: After database searching and screening, 7,797 cases were finally included according to the criteria. The early pain relief rates were 94.1% (1,551/1,649) and 89.9% (4,962/5,482) following PBC and MVD (odds ratio [OR] = 0.603; p < 0.05), while the long-term rates were 58.1% (921/1,566) and 74.9% (4,549/6,074; OR = 2.089; p < 0.05), respectively. Although a significant higher facial numbness occurred in the PBC group in the early stage, it was mostly diminished 5 years later compared with the MVD group. At long-term follow-up, hypoacusis and facial palsy occurred more often in the MVD group (p < 0.05). CONCLUSIONS: Both MVD and PBC provide a satisfactory outcome for the patients in the long term. As a simple, safe, and reliable technique, PBC should be considered as a viable alternative.

Microvascular decompression for pediatric onset trigeminal neuralgia: patterns and variation.

OBJECTIVES: Pediatric trigeminal neuralgia has been rarely reported in the literature, which were only 28 cases. Although microvascular decompression (MVD) has been widely accepted as effective therapy for trigeminal neuralgia, the etiology and surgical treatment of pediatric ones are seldom addressed. We report our experience with MVD for pediatric trigeminal neuralgia patients with emphasis on the vascular conflict patterns and surgical skills. METHODS: This retrospective report included 11 pediatric TN patients, who underwent MVD and were followed for 3-86 months. The data were retrospectively analyzed with emphasis on the clinical features. RESULTS: This series included 4 boys and 7 girls with average age of 13 ± 3.4 years old, their onset age were from 7 to 18 years old. The singular vein and combined artery/vein conflictions account for 7/11. 9 (81.8%) patients achieved immediate excellent outcomes. One recurrence was observed after 5 months and refused the second surgery. CONCLUSIONS: The etiology of pediatric onset trigeminal neuralgia is still vascular conflict, whose patterns are different from adults, of which combined artery/vein and singular venous compression patterns have a much more higher proportion. Because of the smaller operative space and fragile-thin venous wall with adhesion to other structures, it is much more difficult to decompress the trigeminal nerve among pediatric patients. Sufficient arachnoid release, full exploration, and decompression along the trigeminal nerve were necessary, which will increase the excellent rate among pediatric patients.

Treatment of Trigeminal Neuralgia with "Microvascular Decompression Plus" Technique.

Objective Although microvascular decompression (MVD) has been widely accepted as an effective treatment of trigeminal neuralgia (TN), some patients have not been cured. To improve the postoperative outcome, the surgical procedure should be further refined. Design This is a retrospective study. Setting Present study conducted at a cranial nerve disorder center. Participants Clinical data were collected from patients with TN who had undergone surgery in our center, including 685 who had undergone traditional MVD and 576 who had undergone the "MVD plus" procedure, in which any vessel attached to the trigeminal nerve was freed away ("nerve-combing"), which was followed by intraoperative neurolysis. Main Outcome Measures Postoperative outcomes and complications in the two groups were compared. Results Among patients who underwent traditional MVD, the rates of immediate relief and 1-year relief were 89.9 and 86.9%, respectively; among patients who underwent MVD plus group, these rates were 95.1 and 94.6%, respectively ( p = 0.05). Patients who underwent MVD plus initially exhibited a higher rate of facial numbness ( p < 0.05), but this finding decreased over time and reached the same level as that in the traditional MVD group within 3 months ( p > 0.05). Conclusion Sufficient MVD with nerve-combing for the treatment of TN may produce a high rate of cure with less recurrence.

The effect of IL-6/Piezo2 on the trigeminal neuropathic pain.

The nature of trigeminal neuropathic pain (TN) attacks is regarded as the ignition of ectopic action potentials from the trigeminal root following vascular compression, which seemed to be related to transmembrane proteins and inflammation factors. This study focused on the mechanosensitive channel Piezo2 and cytokine IL-6. The chronic constriction injury of infraorbital nerve in SD rats was used to establish the TN model. The trigeminal ganglion was then achieved to perform immunocytochemistry studies. A significant upregulation of Piezo2 and IL-6 was showed in the TN model rats. The Piezo2 positive accounted for 72.3±9.5% in those IL-6 positive neurons. The Piezo2 co-localized with CGRP, IB4 and NF-200 but not with GFAP, which implied that it was expressed in both the C-type and the A-type neurons. After administration of GsMTx4 or anti-rat IL-6 antibody in the TN model, the dynamic allodynia and pinprick hyperalgesia scores as well as the mechanical threshold changed significantly. In the sham-operation rates, with local administration of IL-6, an upregulation of Piezo2 was also exhibited. Our study demonstrated that the up-regulation of Piezo2 in the pain afferent neurons following trigeminal nerve injury may play a role in the development of the neuralgia. Meanwhile, the expression of Piezo2 may be modulated by inflammatory cytokines, such as IL-6.

IL-6 contributes to Nav1.3 up-regulation in trigeminal nerve following chronic constriction injury.

Background: To verify the hypothesis that the nature of trigeminal neuralgia (TN) is an ectopic impulse induced by sodium channel modulated by cytokines, we conducted an animal study using the infraorbital nerve chronic constriction injury (CCI) model in rats.Method: The expression of Nav1.3 or IL-6 in the infraorbital nerve (ION) and trigeminal ganglion (TG) were detected by western blot and immunocytochemistry after administration of antisense oligodeoxynucleotide sequence (AS), IL-6 or Anti-IL-6.Results: With intrathecal administration of AS or mismatch oligodeoxynucleotide sequence (MM) in the CCI rats, the Nav1.3-IR in ION and TG accounted for 2.2 ± 0.51% and 8.5 ± 3.1% in AS+CCI group vs. 6.9 ± 1.3% and 38.7 ± 4.8% in MM+CCI group (p < 0.05), respectively. While with local administration of IL-6 in those with sham operation, it accounted for 7.4 ± 2.1% and 45.5 ± 3.4% in IL-6+ sham group vs. 1.9 ± 0.67% and 8.1 ± 1.3% in vehicle+sham group (p < 0.05); with local administration of anti-IL-6 in CCI rats, 4.5 ± 0.78% and 32.1 ± 9.6% in Anti-IL-6+ CCI group vs 8.9 ± 2.1% and 61.4 ± 11.2% in vehicle+CCI group (p < 0.05).Discussion: We believe that the emergence of Nav1.3 from the compressed trigeminal nerve might be an important structural basis for the development of the ectopic excitability on the axon and IL-6 may play a role of necessary precondition.

The expression of voltage-gated sodium channels in trigeminal nerve following chronic constriction injury in rats.

Objectives: Despite the etiology of trigeminal neuralgia has been verified by microvascular decompression as vascular compression of the trigeminal root, very few researches concerning its underlying pathogenesis has been reported in the literature. The present study focused on those voltage-gated sodium channels, which are the structural basis for generation of ectopic action potentials. Methods: The trigeminal neuralgia modeling was obtained with infraorbital nerve chronic constriction injury (ION-CCI) in rats. Two weeks postoperatively, the infraorbital nerve (TN), the trigeminal ganglion (TG), and the brain stem (BS) were removed and analyzed with a series of molecular biological techniques. Results: Western blot depicted a significant up-regulation of Nav1.3 in TN and TG but not in BS, while none of the other isoforms (Nav1.6, Nav1.7, Nav1.8, or Nav1.9) presented a statistical change. The Nav1.3 from ION-CCI group was quantified as 2.5-fold and 1.7-fold than that from sham group in TN and TG, respectively (p < .05). Immunocytochemistry showed the Nav1.3-IR from ION-CCI group accounted for 21.2 ± 2.3% versus 6.1 ± 1.2% from sham group in TN, while the Nav1.3-positive neurons from ION-CCI group accounted for 34.1 ± 3.5% versus 11.2 ± 1.8% from sham group in TG. Immunohistochemical labeling showed the Nav1.3 was co-localized with CGRP and IB4 but not with GFAP or NF-200 in TG. Conclusion: ION-CCI may give rise to an up-regulation of Nav1.3 in trigeminal nerve as well as in C-type neurons at the trigeminal ganglion. It implied that the ectopic action potential may generate from both the compressed site of the trigeminal nerve and the ganglion rather than from the trigeminal nuclei.

A correlative analysis between inflammatory cytokines and trigeminal neuralgia or hemifacial spasm.

BACKGROUND: It is necessary to understand the mechanism of trigeminal neuralgia (TN) and hemifacial spasm (HFS) in order to seek for an effective noninvasive remedy. As previous studies implied that inflammatory cytokines induced by demyelination following the nerve injury may be the initiated factor causing neuropathic pain, we attempt to analyze the correlation between cytokines and these hyperactive cranial nerve disorders. METHOD: The consecutive patients whose diagnosis were confirmed by microvascular decompression surgery as primary TN or HFS caused by vascular compression and healthy volunteers between March and May 2018 in XinHua Hospital Shanghai JiaoTong University School of Medicine were recruited. Preoperatively, venous blood was collected and the protein concentrations of IL-1ß, IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ were determined with ELISA. Each cytokine was compared between the patients and healthy volunteers. RESULTS: Ultimately, 28 healthy volunteers as well as 44 TN and 47 HFS patients were enrolled in this investigation. The serum levels of IL-1ß, IL-6, IL-8 and TNF-α in either HFS or TN patients were significantly higher than that in healthy volunteers (p < 0.05), yet which were similar between TN and HFS patients (p > 0.05). Besides, there was a significantly correlation between IL-6 concentration and severity of HFS (r = 0.933, p < 0.05) or TN (r = 0.943, p < 0.05). DISCUSSION: Vascular compression of trigeminal or facial nerve roots may induce a rise in variety of cytokines, and IL-6 may play an important role in the signaling pathways to generate ectopic impulses from these cranial nerves.

Pain threshold monitoring during chronic constriction injury of the infraorbital nerve in rats.

Background: The chronic constriction injury (CCI) of the infraorbital nerve (ION) has been used to establish an animal mode of trigeminal neuralgia (TN), but key parameters of the model have not been quantified until now. Objective: The aim of the study was to quantify a standard of pain threshold to evaluate a successful TN model in Sprague-Dawley (SD) rats. Methods: Forty-eight adult SD rats (200-220 g) underwent chronic constriction injury of the infraorbital nerve. The pain threshold was tested one day preoperatively (baseline) and day 1, 3, 7, 14, 28 postoperatively using the up-down method. At day 28, all the animals were killed by dislocation of the cervical spine and the trigeminal nerve specimens were removed for electron microscopy. Results: The baseline pain threshold was 14.40 ± 0.87 g. Postoperatively, all the rats presented an initial reduced sensitivity to mechanical stimulation from day 1 (15.63 ± 1.92 g) through 7 (17.39 ± 1.43 g) after the surgery. At day 14, 32 (66.7%) began to show significant mechanical allodynia (0.71 ± 0.43 g) which did not change significantly till day 28 (0.88 ± 0.54 g). These animals were regarded as successful TN models with a 95% confidence interval of the pain threshold of 0.58-1.27 at Day 14. The electron microscopy demonstrated homogeneously demyelinated changes in those successful TN model animals rather than severe or mild epineurial lesions in those unsuccessful model animals. Conclusion: Our study showed that an animal TN model could be established with a two-week chronic constriction injury of the infraorbital nerve. The mechanical allodynia index <1.27 at Day 14 was suggested as a criterion for a successful model.

A Novel C2 Screw Trajectory: Preliminary Anatomic Feasibility and Biomechanical Comparison.

BACKGROUND: Pedicle screw and translaminar screw fixation in C2 may not be applicable in many patients with anatomic abnormalities or narrow laminar thickness and spinous process height. The aim of this study was to assess morphometric and mechanical feasibilities of a novel alternative screw trajectory that pierces the bifid base of C2. METHODS: Anatomic measurements that determined the feasibility of spinous process bifid base (SPB) screw fixation were assessed in 14 cadaveric C2 vertebrae. Pullout tests to assess ultimate fixation strength for 3 screw trajectories (transpedicular, translaminar, and SPB) were performed in cadaveric vertebrae for comparison. RESULTS: Anatomic measurements included mean spinous process height (10.4 ± 4.2 mm) and mean bilateral bifid base length (10.1 ± 2.2 mm) and thickness (left, 4.4 ± 1.0 mm; right, 4.3 ± 0.9 mm). In 64% (9/14) of specimens, bifid base length was ≥9 mm. Mean pullout strength for transpedicle, translaminar, and SPB screws in 9 viable specimens was 648 ± 305 N, 628 ± 417 N, and 755 ± 279 N. CONCLUSIONS: SPB screw fixation may be viable anatomically and mechanically for C2 fixation. Feasibility of SPB screw fixation is determined by length, thickness, and mutual angle of the bilateral bifid bases. Patients with thin (<4 mm) and short (<9 mm) bifid bases are not likely to be suitable candidates. SPB screw fixation shows potential as an alternative approach or a salvage technique for patients with high-riding vertebral arteries or severely thin C2 lamina and warrants further investigation.

A comparative study of intraoperative findings and postoperative outcomes between atypical and typical hemifacial spasms.

In most hemifacial spasm cases, the spasm initiates from the orbicularis occuli muscle and gradually spreads downwards to the orbicularis oris and buccinator muscles. Seldomly, the spasm might start from the orbicularis oris and buccinator muscles and develop upwards, which has been called as atypical hemifacial spasm (aHFS). Until now, little is known about its pathogenesis and the efficacy of microvascular decompression (MVD) surgery. We reviewed 1935 HFS cases undergoing MVD between 2007 through 2016. Among them, 15 were diagnosed as aHFS, whom were focused on. Their intraoperative findings and postoperative outcomes were compared with those typical hemifacial spasm (tHFS) cases. In the aHFS group, the conflict site was found in the root exit zone (REZ) in 12 (rostral 9, dorsal 2, and ventral 1) and in the cisternal segment in 3. In the tHFS group, the conflict site was found in the REZ in 1812 (rostral 6, caudal 1734, dorsal 12, and ventral 60) and in the cisternal segment in 108. The rostral REZ seemed to be the most frequent neurovascular conflict site in aHFS compared to the caudal REZ in tHFS (p < 0.05). Postoperatively, the effective rate of MVD was 93.3% in the aHSF group, while 96.3% in the tHSF group (p > 0.05). It was demonstrated that MVD may also lead to a satisfactory outcome for aHFS. Although the caudal REZ of the facial nerve is a frequent conflict site for most of the hemifacial spasm cases, the rostral side or cisternal segment of the facial nerve root should not be ignored while searching for the offending artery.

Microvascular decompression for glossopharyngeal neuralgia: a retrospective analysis of 228 cases.

BACKGROUND: Glossopharyngeal neuralgia (GPN) is an uncommon craniofacial pain syndrome caused by neurovascular conflict. Compared to trigeminal neuralgia or hemifacial spasm, the incidence of GPN was very low. Until now, little is known about the long-term outcome following microvascular decompression (MVD) process. METHODS: Between 2006 and 2016, 228 idiopathic GPN patients underwent MVD in our department. Those cases were retrospectively reviewed with emphasis on intraoperative findings and long-term postoperative outcomes. The average period of follow-up was 54.3 ± 6.2 months. RESULTS: Intraoperatively, the culprit was identified as the posterior inferior cerebellar artery (PICA) in 165 cases (72.3%), the vertebral artery (VA) in 14 (6.1%), vein in 10 (4.4%), and a combination of multiple arteries or venous offending vessels in 39 (17.2%). The immediately postoperative outcome was excellent in 204 cases (89.5%), good in 12 (5.3%), fair in 6 (2.6%) and poor in 6 (2.6%). More than 5-year follow-up was obtained in 107 cases (46.9%), which presented as excellent in 93 (86.9%), good in 6 (5.6%), fair in 3 (2.8%) and poor in 5 (4.7%). Thirty-seven (16.2%) of the patients experienced some postoperative neurological deficits immediately, such as dysphagia, hoarseness and facial paralysis, which has been improved at the last follow-up in most cases, except 2. CONCLUSIONS: This investigation demonstrated that MVD is a safe and effective remedy for treatment of GPN.

Anterior Cervical Discectomy and Fusion with a Compressive C-JAWS Staple.

BACKGROUND: Anterior cervical discectomy and fusion is currently the most commonly used technique in cervical surgery. But the implantation of a traditional plate is time-consuming and exposes the patient to additional adverse events. In this study, we analyzed results in patients who underwent anterior cervical discectomy and fusion with C-JAWS fixation. The C-JAWS device is a new cervical compressive staple developed to stabilize the spacer. METHODS: At our department, between January 2012 and December 2013, nine consecutive patients with cervical spondylopathy underwent an anterior cervical discectomy and fusion process in which we used a polyether ether ketone cervical spacer prefilled with bone substitute and secured with a cervical compressive staple. The Neck Disability Index (NDI) score and visual analog score (VAS) for neck and arm pain, as well as radiographic examinations, were adopted to assess postoperative outcome and fusion. RESULTS: Bony fusion was observed in all of the nine patients, and no serious surgery-related or implant-related complications were observed during the operation or in the postoperative period. The average operative time was 60.3 ± 11.6 min. The average hospital stay was 3.2 ± 0.8 days. The average skin incision length was 3.0 ± 0.3 cm. The average follow-up was 18.4 ± 4.3 months. At the last follow-up, the NDI had changed from the baseline value of 23.4 ± 10.3 to 7.1 ± 4.8, and the VAS values for neck and arm pain had changed from 6.1 ± 1.0 and 4.6 ± 1.6,respectively, to 2.3 ± 1.7 and 2.4 ± 1.1, respectively. The patients' subjective satisfaction was excellent in six and good in three. CONCLUSIONS: Without screws, this low-profile design compressive staple, the C-JAWS, performed well in anterior cervical discectomy and fusion surgeries.

The Significance of Abnormal Muscle Response Monitoring During Microvascular Decompression for Hemifacial Spasm.

BACKGROUND: Despite the wide adoption of the abnormal muscle response (AMR) to electrical stimulation of the facial nerve during microvascular decompression (MVD) surgery, the value of AMR in the prognosis of the postoperative outcome is still controversial. In order to better use this intraoperative electrophysiology, it is necessary to further address the relationship between AMR and postoperative results. METHODS: Three hundred and thirty-two patients with hemifacial spasm (HFS) in whom MVD surgery was performed and in whom AMR was available were finally enrolled in this study. The intraoperative AMR changes were classified as amplitude ≥ 50 %, <50 %, and disappearance. These changes were retrospectively analyzed in association with intraoperative findings and postoperative outcomes. The follow-up period ranged from 11 to 62 months, with an average of 34.1 months. RESULTS: Among the 332 patients with a typical AMR wave recorded at the beginning of the operation, the AMR disappeared in 305, and amplitude was <50 % in 11 and ≥50 % in 16. Of those with AMR disappearance plus those with amplitude < 50 %, 98.4 % achieved relief on the first postoperative day and at the latest follow-up, while of those with amplitude ≥50 %, 18.8 % and 25 %, respectively, achieved relief on the first postoperative day and at the latest follow-up (P < 0.01). Accordingly, a more than 50 % decrease of AMR amplitude may predict a good prognosis. The accuracy, sensitivity, and specificity of AMR monitoring were 97.5 %, 99 %, and 72.2 %, respectively. CONCLUSIONS: AMR could be a good tool for successful MVD in patients with HFS when a rational analysis is conducted in association with the intraoperative findings. Persistence of AMR may imply that the real offending vessel was missed. If the entire facial nerve root is cleared of any vessel, a remaining AMR amplitude of less than 50 % might be acceptable. Otherwise, neurocombing is suggested before finishing the operation.

One-Pot Aqueous Synthesization of Near-Infrared Quantum Dots for Bioimaging and Photodynamic Therapy of Gliomas.

BACKGROUND: As the early detection and total destruction of gliomas are essential for longer survival, we attempted to synthesize a quantum dot (QD) that is capable of recognizing glioma cells for imaging and photodynamic therapy. METHODS: Using a one-pot aqueous approach, near infrared-emitting CdTe was produced. After detection of its physicochemical characteriistics, it was conjugated with RGD. The emission images were observed with confocal microscopy. To test its toxicity, CdTe-RGD at various concentrations was separately added to a human glioma cell line (U251) and a mouse embryo fibroblast cell line (3T3) (control) for incubation in dark conditions. To test its photodynamic effect, the U251 and 3T3 cells were then irradiated for 5-60 min, using a 632.8-nm laser. RESULTS: This QD (Φ = 3.75 nm, photoluminescence (PL) peak wavelength = 700 nm, photoluminescence quantum yield (PLQY) = 20 %), was a spherical crystal with excellent monodispersity. Under a confocal microscope, U251 cells were visualized, but not the 3T3 cells. In dark conditions, the survival rates of both U251 and 3T3 cells were above 85 %. After laser irradiation, the survival rate of U251 cells decreased to 37 ± 1.6 % as the irradiation time and the CdTe-RGD concentration were increased. CONCLUSIONS: With good physicochemical characteriistics and low toxicity, this QD-RGD has broad prospects for use in the biomedical imaging and photodynamic therapy of gliomas.