Wenxiang Zhong

Evaluation of the clinical efficacy of multiple lower-extremity nerve decompression in diabetic peripheral neuropathy.

Abstract Objective. To evaluate the value of high-resolution ultrasonography and neural electrophysiology in early diagnosis, operative opportunity selection, and clinical effect assessment of DPN. Methods. Five hundred and sixty patients with diabetic peripheral neuropathy (DPN) were treated with DELLON surgical nerve decompression in our hospital in the past 5 years. Before and after 18 months surgery, the tests of the Toronto clinical scoring system, high-resolution ultrasonography, QST, and Nerve Conduction Velocity (NCV) were evaluated in all cases. The control group included 40 diabetic patients in the same age range but without DPN. Results. Ultrasonographic images revealed an apparently normal proximal common peroneal nerve, tibial nerve marked swelling, enlarged, and hypoechogeneity with loss fascicular pattern. The cross-sectional-area, anteroposterior and transverse diameter were measured preoperative and prooperative, and the differences had statistical significance（P < 0.01）. NCV-positive cases amount to 74.9% DPN patients in this study and QST-positive cases amount to 90.9% and had significant differences between them (P < 0.05). Postoperative NCV and cold perception threshold significantly increased (P < 0.05) compared with that of the before surgery. Postoperative warm perception threshold (P < 0.01) and vibration perception threshold (P < 0.05) were significantly lower than the preoperative value. NCV was positively correlated with cold perception threshold (r = 0.395, P < 0.01), and negatively correlated with warm perception threshold (r = − 0.387, P < 0.01) and vibratory perception threshold (r = − 0.367, P < 0.01). The preoperative TCSS score was 19 points for all the cases, and 420 cases (75%) improved to 10–13 points (P < 0.01). Conclusion. Ultrasonography is capable of depicting these nerves morphological information, with respect to exact location, course, and extent. QST is suitable for early diagnosis of DPN, and abnormal QST is an indication of lower extremity nerve decompression for DPN. The joint use of QST and NCV testing helps surgeons to grasp the timing of surgery. High-resolution ultrasound, QST and NCV testing can also be used as an outcome index for surgical treatment.

Neuronavigator-guided percutaneous radiofrequency thermocoagulation in the treatment of trigeminal neuralgia.

BackgroundAlthough radiofrequency thermocoagulation is considered as a primary treatment for most patients with trigeminal neuralgia, neuronavigator-guided percutaneous radiofrequency thermocoagulation has been rarely reported. The object of this study was to assess the clinical value of neuronavigator-guided percutaneous radiofrequency thermocoagulation in the treatment of trigeminal neuralgia.MethodsThe radiofrequency thermocoagulation was performed in 100 cases of trigeminal neuralgia. The patients were positioned supine or sitting, under Hartel’s technique (reported by Sweet and Wepsic J Neurosurg 40:143–156, 1974), by anterior lateral facial approaches. The Gasserian ganglions were acupunctured, assisted by intraoperative CT scanning (3-digital reconstruction) and electrophysiology in order to accurately locate target.ResultsThe needles located in oval foramen at the first puncture, the direction and position could be defined according to the electrophysiology examination. The pain alleviated immediately after operation. There occurred no serious complication and other nerve injury in all patients despite face numbness only.Conclusions3D-CT and electrophysiology Gasser’s ganglion locations can raise the success rate of puncture, enhance the safety and reduce the incidence of complication, showing high academic value and its promising future.

Clinical characteristics and surgical techniques of trigeminal neuralgia caused simply by venous compression.

ObjectiveThe objective of this study was to introduce the operation essentials for treatment of patients with vein compression so as to obtain a satisfactory decompression without sacrificing veins. MethodsWe chose 15 patients with trigeminal neuralgia caused by venous from June 15, 2010, through June 15, 2011, and performed microvascular decompression for each patient. By collecting clinical data, such as preoperative magnetic resonance imaging scans, key operative procedures, surgical outcomes, and complications, we explored the operation techniques for these patients and finally summarized our experiences and ideas. ResultsFor all the 15 patients, 9 cases had excellent remission, 3 cases had delayed excellent remission, 1 case had good remission, and 2 cases had failed result; the total remission rate was 86.7%; 3 cases had facial numbness. ConclusionsFor patients with vein compression, we combine the following 4 procedures together: (1) fully releasing the arachnoid around trigeminal nerve, (2) exploration and decompression of the whole trigeminal root from Meckel cave to pons, (3) cauterization of companioned petrosal vein tributaries by bipolar coagulation, and (4) placing Teflon between trigeminal nerve and offending petrosal vein, thus could acquire a satisfactory effect (remission rate, 86.7%).

The high-resolution ultrasonography and electrophysiological studies in nerve decompression for ulnar nerve entrapment at the elbow.

OBJECTIVE To discuss a combination of high-resolution ultrasound and electrophysiological examination in diagnosis and evaluation of ulnar nerve entrapment at the elbow. METHOD We retrospectively reviewed 20 healthy volunteers and 278 patients of ulnar nerve entrapment divided into three groups by McGowan grade, and we treated patients with subcutaneous or modified submuscular ulnar nerve transposition randomly. All the patients were followed for 2 years. The diagnosis and effects were confirmed by preoperative or postoperative cross-sectional area (CSA), motor conduction velocity (MCV), sensory conduction velocity, and nerve action potential (NAP). RESULTS Healthy volunteers and grade I patients had significant differences in CSA, MCV, and NAP; grade I, II, and III patients had significant differences in CSA, MCV, and NAP; all patients had significant differences in CSA, MCV, and NAP before and after operations. CONCLUSION High-resolution ultrasound and electrophysiological examination can be used in diagnosis and evaluation of operations of ulnar nerve entrapment at the elbow.

Analysis of therapeutic effect of microvascular decompression surgery on idiopathic hemifacial spasm.

Objective The objective of this paper is to study the therapeutic effect of microvascular decompression surgery on idiopathic hemifacial spasm with compression on different zones of facial nerve. Methods The clinical data of 348 patients with idiopathic hemifacial spasm treated by microvascular decompression surgery were retrospectively analyzed. Patients were divided into 5 groups according to compression on different zones of facial nerve by offending vessels. Root exit point was compressed in 18 patients (group A), transitional zone of brainstem was compressed in 42 patients (group B), attached segment of brainstem was compressed in 35 patients (group C), distal cisternal portion was compressed in 21 patients (group D), and 2 or more zones were compressed in 232 patients (group E). The therapeutic effect was observed, and outcome of excellent and partial good were regarded as effective. Results Patients were followed up for 0.5 to 2 years. The effective rates were 94.4%, 95.2%, 97.1%, 95.2%, and 93.9% in group A, group B, group C, group D, and group E, respectively.No death occurred during operation,and there were no severe complications such as complete facial paralysis, intracranial hematoma, and hearing loss after operation. Conclusion Microvascular decompression surgery is the first choice for treatment hemifacial spasm.Proper detection of offending vessels and complete decompression may be the key factors to increase the cure rate.

Comparative Study of Different Surgical Transposition Methods for Ulnar Nerve Entrapment at the Elbow

This study compared the therapeutic effects of two techniques for surgical decompression treatment for ulnar nerve entrapment at the elbow: subcutaneous transposition and modified submuscular transposition with Z-lengthening of the pronator teres origin. A total of 278 patients with ulnar nerve entrapment (McGowan grades I-III) were randomly assigned to undergo one of these techniques. All patients were followed-up for 2 years. The effects were assessed by preoperative and postoperative cross-sectional area, motor conduction velocity, sensory conduction velocity and nerve action potential. All of these parameters improved after surgery in both groups. For patients with grade I disease, there were no significant differences between the two techniques. For patients with grade II and III disease, modified submuscular transposition was associated with significantly greater improvements compared with subcutaneous transposition. In conclusion, subcutaneous ulnar nerve transposition is recommended for grade I patients and modified submuscular ulnar nerve transposition for grade II and III patients.

Symptomatic Trigeminal Neuralgia Caused by Cerebellopontine Angle Tumors.

To investigate the characteristics of symptomatic trigeminal neuralgia (TN) caused by tumors and the relationship between anatomicosurgical findings and tumor type, the authors undertook a retrospective review of 35 patients with symptomatic TN between 2006 and 2015. The tumors included 16 meningiomas, 14 epidermoids, 4 vestibular schwannomas, and 1 hemangioblastoma. The studies show that patients with tumor-induced TN were significantly younger than those idiopathic TN (P <0.05). Meningioma-induced TN tended to have responsible vessels, while epidermoid tumor seemed to cause TN by wrapping or compressing the nerve. Additional vascular compression was observed in 15 (42.9%) of these 35 patients. All patients except one showed immediate pain relief following total or subtotal tumor removal with microvascular decompression (if required). Two patients with epidermoid-induced TN experienced symptom relapses caused by tumor regrowth, and one with meningioma-induced TN experienced pain recurrence caused by adhesive arachnoid. The key for operative success is to examine the entire nerve root for possible vascular compression after total or subtotal tumor resection.Abstract To investigate the characteristics of symptomatic trigeminal neuralgia (TN) caused by tumors and the relationship between anatomicosurgical findings and tumor type, the authors undertook a retrospective review of 35 patients with symptomatic TN between 2006 and 2015. The tumors included 16 meningiomas, 14 epidermoids, 4 vestibular schwannomas, and 1 hemangioblastoma. The studies show that patients with tumor-induced TN were significantly younger than those idiopathic TN (P <0.05). Meningioma-induced TN tended to have responsible vessels, while epidermoid tumor seemed to cause TN by wrapping or compressing the nerve. Additional vascular compression was observed in 15 (42.9%) of these 35 patients. All patients except one showed immediate pain relief following total or subtotal tumor removal with microvascular decompression (if required). Two patients with epidermoid-induced TN experienced symptom relapses caused by tumor regrowth, and one with meningioma-induced TN experienced pain recurrence caused by adhesive arachnoid. The key for operative success is to examine the entire nerve root for possible vascular compression after total or subtotal tumor resection.

Improved neural microcirculation and regeneration after peripheral nerve decompression in DPN rats

Abstract Objective: Recently, neural microcirculation and regeneration were regarded as critical factors in diabetic peripheral neuropathy (DPN) improvement. In the present study, we explored the cytological and molecular mechanisms how peripheral nerve decompression impaired nerve injury. Methods: Forty-five male SD rats were established as the DPN model. HE staining was used to observe the morphology and distribution of microvessels. Transmission electron microscopy was applied to observe the morphology and distribution of Schwann cells. Immunohistochemical staining was performed to measure nerve growth factor (NGF), tyrosine kinase receptor A (TrkA) and growth-associated protein 43 (GAP-43) in the distal sciatic nerve. Results: Distribution of microvessels and Schwann cells decreased in the DPN group (p < 0.05). NGF, TrkA and GAP-43 also decreased significantly in the DPN group (p < 0.05). NGF, TrkA, GAP-43 and distribution of microvessels and Schwann cells increased in the decompressed group (p < 0.05). Discussion: In DPN rats, after nerves are compressed, microcirculation disturbance and hypoxia ischemia will happen, which cause decreased expression of NGF, TrkA and GAP-43. Finally, the self-healing function of compressed nerves is impacted. Conversely, nerve decompression can improve neural microcirculation and regeneration and change the former pathological process.

Association of myelinated primary afferents impairment with mechanical allodynia in diabetic peripheral neuropathy: an experimental study in rats

To investigate the mechanisms underlying the efficacy of surgical treatment for painful diabetic peripheral neuropathy. Rats were initially divided into 3 groups (I, control rats, II, streptozotocin-induced diabetic rats, III, streptozotocin-induced diabetic rats with latex tube encircling the sciatic nerve without compression). When mechanical allodynia (MA) became stable in the third week, one third of group III rats were sacrificed and the remainder were further divided into subgroups depending on whether the latex tube was removed. Except for some rats in group III, all rats were sacrificed in the fifth week. Morphometric analysis of nerve fibers was performed. Expression level of GABAB receptor protein in spinal dorsal horn was determined. Changes of GABAB receptor within areas of primary afferents central terminal were identified. Chronic nerve compression caused by the interaction of diabetic nerves swelling and the encircling latex tube increased the incidence of MA in diabetic rats, and nerve decompression could ameliorate MA. In diabetic rats with MA, demyelination of myelinated fibers was noted and reduction of GABAB receptor was mainly detected in the area of myelinated afferent central terminals. MA in DPN should be partially attributed to compression impairment of myelinated afferents, supporting the rationale for surgical decompression.To investigate the mechanisms underlying the efficacy of surgical treatment for painful diabetic peripheral neuropathy. Rats were initially divided into 3 groups (I, control rats, II, streptozotocin-induced diabetic rats, III, streptozotocin-induced diabetic rats with latex tube encircling the sciatic nerve without compression). When mechanical allodynia (MA) became stable in the third week, one third of group III rats were sacrificed and the remainder were further divided into subgroups depending on whether the latex tube was removed. Except for some rats in group III, all rats were sacrificed in the fifth week. Morphometric analysis of nerve fibers was performed. Expression level of GABAB receptor protein in spinal dorsal horn was determined. Changes of GABAB receptor within areas of primary afferents central terminal were identified. Chronic nerve compression caused by the interaction of diabetic nerves swelling and the encircling latex tube increased the incidence of MA in diabetic rats, and nerve decompression could ameliorate MA. In diabetic rats with MA, demyelination of myelinated fibers was noted and reduction of GABAB receptor was mainly detected in the area of myelinated afferent central terminals. MA in DPN should be partially attributed to compression impairment of myelinated afferents, supporting the rationale for surgical decompression.

Use of High-Resolution Ultrasonography in Anterior Subcutaneous Transposition of the Ulnar Nerve for Cubital Tunnel Syndrome

OBJECTIVES Cubital tunnel syndrome (CTS) is the most common form of ulnar nerve entrapment. In this study, ultrasonography (US) was used not only for diagnosis but also for operation. US findings could be used to establish the diagnosis of CTS and could demonstrate the pathological anatomy in the cubital tunnel region to guide anterior subcutaneous transposition of the ulnar nerve. METHODS Sixty-two patients with clinical and electrophysiological evidence of ulnar nerve entrapment were included. All patients received ultrasonographic examination and anterior subcutaneous transposition of the ulnar nerve. The maximal diameter of the ulnar nerve (MDU) was measured in longitudinal views and the range of the hypoechoic area around the nerve was observed. The cross-sectional area (CSA) was also measured on transverse scans. The actual MDU was measured during operation. RESULTS The actual MDU was 6.4 ± 0.4 mm, measured during operation. The preoperative MDU was 3.1 ± 0.2 mm. The MDU values recorded in CTS patients were greater than those in normal subjects. The range of the hypoechoic area observed on longitudinal US scans was 2.9-5.6 mm (mean, 4.1 ± 0.4 mm). CONCLUSIONS High-resolution US can be used not only in the diagnosis of CTS, also for providing effective preoperative evaluation for the anterior subcutaneous transposition of the ulnar nerve in CTS.