Yucel Kanpolat

Percutaneous Controlled Radiofrequency Trigeminal Rhizotomy for the Treatment of Idiopathic Trigeminal Neuralgia: 25-year Experience with 1600 Patients

OBJECTIVEThe objective of this study was to evaluate the effectiveness of percutaneous, controlled radiofrequency trigeminal rhizotomy (RF-TR). The outcome of 1600 patients with idiopathic trigeminal neuralgia after RF-TR was analyzed after a follow-up period of 1 to 25 years. METHODSA total of 1600 patients with idiopathic trigeminal neuralgia underwent 2138 percutaneous radiofrequency rhizotomy procedures between 1974 and 1999. Sixty-seven patients had bilateral idiopathic trigeminal neuralgia, and 36 of them were treated with bilateral RF-TR; 1216 patients (76%) were successfully managed with a single procedure, and the remainder were treated with multiple procedures. Benzodiazepines and narcotic analgesics were used for anesthesia because patient cooperation during the procedures was essential so that the physician could create selective, controlled lesions. RESULTSThe average follow-up time was 68.1 ± 66.4 months (range, 12–300 mo). Acute pain relief was accomplished in 97.6% of patients. Complete pain relief was achieved at 5 years in 57.7% of the patients who underwent a single procedure. Pain relief was reported in 92% of patients with a single procedure or with multiple procedures 5 years after the first rhizotomy was performed. At 10-year follow-up, 52.3% of the patients who underwent a single procedure and 94.2% of the patients who underwent multiple procedures had experienced pain relief; at 20-year follow-up, 41 and 100% of these patients, respectively, had experienced pain relief. No mortalities occurred. After the first procedure was performed, early pain recurrence (<6 mo) was observed in 123 patients (7.7%) and late pain recurrence was observed in 278 patients (17.4%). Complications included diminished corneal reflex in 91 patients (5.7%), masseter weakness and paralysis in 66 (4.1%), dysesthesia in 16 (1%), anesthesia dolorosa in 12 (0.8%), keratitis in 10 (0.6%), and transient paralysis of Cranial Nerves III and VI in 12 (0.8%). Permanent Cranial Nerve VI palsy was observed in two patients, cerebrospinal fluid leakage in two, carotid-cavernous fistula in one, and aseptic meningitis in one. CONCLUSIONPercutaneous, controlled RF-TR represents a minimally invasive, low-risk technique with a high rate of efficacy. The procedure may safely be repeated if pain recurs.

A New Classification for Facial Pain

PURPOSEA patient-oriented classification scheme for facial pains commonly encountered in neurosurgical practice is proposed. CONCEPTThis classification is driven principally by the patient’s history. RATIONALEThe scheme incorporates descriptions for so-called “atypical” trigeminal neuralgias and facial pains but minimizes the pejorative, accepting that the physiology of neuropathic pains could reasonably encompass a variety of pain sensations, both episodic and constant. Seven diagnostic labels result: trigeminal neuralgia Types 1 and 2 refer to patients with the spontaneous onset of facial pain and either predominant episodic or constant pain, respectively. Trigeminal neuropathic pain results from unintentional injury to the trigeminal nerve from trauma or surgery, whereas trigeminal deafferentation pain results from injury to the nerve by peripheral nerve ablation, gangliolysis, or rhizotomy in an intentional attempt to treat either trigeminal neuralgia or other facial pain. Postherpetic neuralgia follows a cutaneous herpes zoster outbreak (shingles) in the trigeminal distribution, and symptomatic trigeminal neuralgia results from multiple sclerosis. The final category, atypical facial pain, is synonymous with facial pain secondary to a somatoform pain disorder. Atypical facial pain can be suspected but not diagnosed by history and can be diagnosed only with detailed and objective psychological testing. CONCLUSIONThis diagnostic classification would allow more rigorous and objective natural history and outcome studies of facial pain in the future.

Various surgical modalities for trigeminal neuralgia: literature study of respective long-term outcomes.

SummaryBackground. The literature contains many varying, often conflicting surgical results. However, there is no study comparing long-term effectiveness of all surgical procedures for trigeminal neuralgia (TN). The aim of the present analysis is to report the long-term outcomes of surgical options of TN since the development of electronic databases, to evaluate them with the same clinical and statistical criteria and determine the most appropriate treatment.Method. All studies that had a minimum 5 years or more (≥5 years) mean duration of follow-up were included in the review. The identified studies were evaluated independently by two authors for quality using a modified inclusion criteria. The evaluated outcome measures of this study were, the initial acute pain relief (APR), follow-up pain free period and recurrence rates as well as complications. In comparisons of the data, the Student’s t-test, Chi-square followed by Pearson’s risk analysis tests were used. Kaplan–Meier actuarial analysis of pain free-survival curves were constructed for each surgical option that had enough data.Findings. Twenty-eight studies, mostly including microvascular decompression (MVD) and radiofrequency thermorhizotomy (RF-TR), that met the inclusion criteria were included in the review. The efficacy of MVD and percutaneous balloon microcompression (PBC) were similar (Odds ratio = 0.15, P > 0.05), and their effects were superior to those of the other modalities (P < 0.001). Although RF-TR provided a high initial pain relief, its average pain free rate was 50.4% for a mean follow-up of 5 years. The recurrence rate was high after RF-TR (46%), while the lowest recurrence rate (18.3%) was after MVD (P < 0.001). Within the long-term follow-up period recurrence of pain affects at least 19% of patients who undergo any surgical treatment for TN.Conclusions. The study suggests that each surgical technique for treatment of trigeminal neuralgia has merits and limitations. However, MVD provides the highest rate of long-term patient’ satisfaction with the lowest rate of pain recurrence.

Ultrastructural evaluation of pulsed radiofrequency and conventional radiofrequency lesions in rat sciatic nerve

BACKGROUND PRF treatment has recently been described as minimally neurodestructive alternative to radiofrequency heat lesions. Patients with some pain syndromes in whom the pain could not be controlled by alternative techniques may be treated using PRF. In the present study, our main goal was to evaluate and compare the ultrastructure of peripheral nerve tissue that was heated by PRF, CRF with 42 degrees C, and CRF with 70 degrees C. METHODS Forty-five male rats were divided into 5 groups. In PRF group and CRF with 42 degrees C group, the sciatic nerve was heated at a temperature of 42 degrees C for 120 seconds. As a positive control, some rat sciatic nerves were treated with CRF lesions at 70 degrees C. The rats were kept alive for 21 days and then killed. Tissue was evaluated with transmission electron microscope, and grading was done to the groups. RESULTS The unmyelinated nerve fibers were ultrastructurally normal in all groups. The results of myelinated axons indicated that PRF group had better grades, and CRF with 70 degrees C group had the worst grade. Especially, comparison of the group of PRF and CRF with 42 degrees C revealed significant difference. In PRF group, none of the myelinated axons showed severe degeneration findings, and most of the damaged myelinated axons showed only separation in myelin configuration. CONCLUSIONS PRF treatment may cause separation in myelinated axons. However, it seems that all changes were reversible. The present study supports the hypothesis that pulsed RF treatment does not rely on thermal injury of neurologic tissue to achieve its effect.

CT-guided percutaneous cordotomy.

Percutaneous cordotomy is a commonly applied and effective procedure among the ablative pain surgeries. As plain X-ray does not permit visualization of the target relative to the electrode the chances of obtaining good results are decreased and the risk of complications are increased. The use of CT has been found to be useful in cordotomy. The procedure is performed under CT control on the patients who have previously been given 5 ml iohexol into the subarachnoid space. The needle electrode is manipulated by free hand technique. It is possible to measure the diameter of the spinal cord and to detect cord dislocation in the spinal canal. When the electrode system is introduced it is possible to visualize the tip of the electrode which is pushing or puncturing the spinal cord. As the procedure directly visualizes the relation of the electrode to the target it is possible to place the electrode in the lateral spinothalamic tract. Another advantage of the procedure is to enable us to visualize haematomas or other changes that may result from the cordotomy. The application of the technique and clinical results will be presented.

Percutaneous Controlled Radiofrequency Rhizotomy in the Management of Patients with Trigeminal Neuralgia due to Multiple Sclerosis

Summary Between the years 1974 and 1999, 1,672 patients with medically intractable trigeminal neuralgia (TN) were treated by percutaneous controlled radiofrequency (RF) rhizotomy by the senior author and co-workers at the Department of Neurosurgery, Ankara University School of Medicine. Sixteen hundred cases (95.7%) were found to have idiopathic TN, while 72 cases (4.3%) were classified as symptomatic. In the latter group, TN was found to be caused by multiple sclerosis (MS) in 17 cases (23.6%), one of whom had bilateral TN. All patients having TN with MS (17 cases) underwent percutaneous controlled radiofrequency rhizotomy (25 procedures) as the procedure of choice. The MS patients were followed for an average of 60 months (range: 6–141 months). Complete pain relief was achieved with a single procedure in 12 of the 17 MS cases (70.6%). Early (less than 2 weeks) pain recurrence was seen in two patients (11.8%), while the overall recurrence rate was 29.4%. A second procedure was required to control TN in three cases (17.6%), a third in one (5.9%), and twice for each side for the case with bilateral TN (5.9%). Pain was completely relieved in 14 cases (82.4%) with single or multiple RF rhizotomies. In three cases (17.6%), partial pain control was achieved with RF rhizotomy, and the patients continued to receive adjunctive medical therapy. No complications were observed. All 17 patients (100%) were classified to have done well with RF rhizotomy. Satisfactory results and good long-term pain control were obtained in patients having TN due to MS with percutaneous controlled RF rhizotomy. The authors propose that RF rhizotomy may be a safe and effective procedure in the neurosurgical armamentarium for the treatment of patients having TN due to MS.

CT-guided trigeminal tractotomy

SummaryTrigeminal tractotomy is an effective procedure in denervating pain areas of 5th, 7th, 9th and 10th nerves. The classical imaging technique is the x-ray method which visualizes the target electrode relation indirectly. The method of CT-guided trigeminal tractotomy demonstrates the target electrode relation directly.

CT-guided percutaneous Selective Cordotomy

SummaryIn this article the technique of CT-Guided Selective Cordotomy is described. The advantages of CT guidance in percutaneous cordotomy are the measurement of spinal cord diameters at the lesion site for each individual patient, direct visualization of target electrode relations, demonstration of spinal cord displacement during the procedure and localization of the electrode system in a specific part of the spinothalamic tract. Local destruction of the spinothalamic tract leads to selective cordotomy.Since 1987, CT-Guided Cordotomy has been applied to 54 cases of intractable cancer pain. In 33 of the 54 cases, the cordotomy was selective enough to be successful with a local denervation of the area where the pain was dominant. Except for one temporary hemiparesis and one temporary ataxia, no complications or side effects were observed.

Meningiomas of the tuberculum sella.

A series of 88 consecutive patients operated on for tuberculum sellae meningioma at the Neurosurgery Department of the University of Ankara Medical School was reviewed. Visual impairment was the most common initial complaint. All but 9 patients had visual symptoms. All patients underwent craniotomy, with an operating microscope being used in 62 cases. Use of the operating microscope appeared to increase the total removal rate while lowering the mortality. In our series visual function improved in 53.5%, was unchanged in 27.5%, and worsened in 19% of the patients.

CT guided extralemniscal myelotomy

SummaryCT guided Extralemniscal Myelotomy (E.M.) is described. Direct visualization of the target is the main advantage of the method. The method was applied successfully in two patients.