Search

Background: Conventional percutaneous thermocoagulation of postgasserian fibers has shown high success rates, with significant residual morbidity., Methods: This communication summarizes conclusions of multiple publications on our computerized mapping method and technique, and presents new data on short- and long-term results on trigeminal pain, including an actuarial analysis, complications., Results: In TTN, 97.4% of 75 procedures produced initial pain relief without medication. In all, 84.7% of appropriate verbal responses were achieved by proper location of the needle at the chosen target, requiring an average of 1.45 tracts per procedure. Needle tip was located between 1 and 15 mm below the sellar floor in 97.0% of procedures and in an angle of 40 degrees to 80 degrees regarding the clivus profile projection in 99.1%. A 93% reduction of corneal analgesia and a 100% suppression of major dysesthesias and cranial nerve palsies were found., Conclusion: We have shown a significant reduction of morbidity from percutaneous thermocoagulation of postgasserian fibers with similar short- and long-term results as those shown in 11 recently selected series. Strict adherence to all details of our new method and technique is essential. Future multiinstitutional studies are needed to confirm and enrich this small series.

The authors present a retrospective study of 121 patients treated with balloon compression of the rootlets behind the Gasser ganglion from 1995 to 2007. The inclusion criteria were drug-resistant idiopathic trigeminal neuralgia. The authors described the surgical technique and compared their results with results from the literature. The following parameters were compared: technical success, pain relief and recurrence, and complications. Balloon compression is considered in the literature to be a safer procedure than other percutaneous surgeries, especially for postoperative sensitive disorders. The best indications seem to be trigeminal neuralgia in older patients or pain due to multiple sclerosis and neuralgia involving the V1 territory. These conclusions should be confirmed by larger series, a longer follow-up (> 5 years) and statistically better analysis.

The percutaneous Hartel transoval route goes through an inverted pyramid, with an inferior summit and a superior base that includes three compartments. The danger of the inferior compartment is the parotid duct. The middle compartment contains many branches of the mandibular nerve. The superior compartment is crossed by the internal maxillary artery and its branches, as well as the auditory tube. The base of the pyramid presents not only the foramen ovale, but also the foramen lacerum, where the trocar may injure the internal carotid, and the foramen jugulare, where the trocar may meet the internal jugular vein and nerves of the pars nervosa (IX, X, XI). The trigeminal cave contains, within the trigeminal cistern, the trigeminal ganglion, extended backward by the triangular plexus (the target for thermocoagulation). These structures are undercrossed by the masticatory motor branch of the trigeminal nerve.

Background: Percutaneous balloon compression of the gasserian ganglion is an effective management of trigeminal neuralgia and is the only percutaneous procedure that preferentially may be performed under general anesthesia. However, the anatomy of Meckle's cave dictates the degree of compression, and if capacious, the usual smaller balloons may fail to adequately compress the ganglion., Methods: We designed a series of larger cannulas, placed over a guidewire technique for using larger balloons, or even multiple balloons, to increase the applicability of this technique in these patients., Results: In select cases, where smaller balloons fail to distort and deform the ganglion, with resultant poor clinical results, larger or multiple balloons may produce the desired response of pain relief., Conclusion: This technique is an added resource in managing this condition.

Background: Of 756 percutaneous controlled radiofrequency thermocoagulations of gasserian ganglion and/or retrogasserian rootlets for idiopathic trigeminal neuralgia or for trigeminal neuralgia in multiple sclerosis, the results in 158 patients who had isolated third division trigeminal neuralgia were reviewed., Methods: In 129 patients, percutaneous thermocoagulation was fluoroscopic guided, whereas in the last 29 the procedure was performed under CT control. In all cases, the goal was to achieve selective anesthesia limited to the third trigeminal division., Results: Complete pain relief was obtained immediately after the procedure in all patients and selective anesthesia in the third division was achieved in all of them, except for 2 patients in whom unwanted first and second division anesthesia/hypoesthesia also occurred. Other significant complications were transient sixth cranial nerve palsy in 1 patient and masseter muscle dysfunction, which improved during follow-up, in another one. The selected sensory impairment was well tolerated in all patients. During an average follow-up period of 8.8 years, recurrences occurred in 12 patients, together with a partial regression of the anesthesia: in 10 patients the procedure was repeated successfully. In 2 patients with multiple sclerosis, the procedure was repeated twice and 3 times, respectively., Conclusions: Percutaneous controlled radiofrequency thermocoagulation is quite easy to perform under fluoroscopic or CT control, and it involves no mortality and very low morbidity; it is an immediately effective procedure and the rate of recurrence is low. Last, but not least, if the anesthesia is limited to the third division, no anesthesia dolorosa occurs and patients are very grateful.

Aims: The main purpose of this study is to underline the factors which are likely to increase the risk of a sixth nerve injury after percutaneous balloon compression of the gasserian ganglion., Methods: Medical records and intraoperative radiological images of 79 consecutive patients, who underwent percutaneous balloon compression for treating drug-resistant trigeminal neuralgia, were analyzed., Results: Post-operatively, transient palsy of the sixth nerve developed in 2 patients. According to their intraoperative radiographs, the side effect resulted from irregular balloon shape and inflation of the balloon towards the sellar floor., Conclusion: The anatomic position and the shape of the inflated balloon represent key factors in determining the procedure's benefit or risk of complications., ((c) 2009 S. Karger AG, Basel.)

Several issues regarding diagnosis, pharmacological treatment, and surgical treatment of trigeminal neuralgia (TN) are still unsettled. The American Academy of Neurology and the European Federation of Neurological Societies launched a joint Task Force to prepare general guidelines for the management of this condition. After systematic review of the literature the Task Force came to a series of evidence-based recommendations. In patients with TN MRI may be considered to identify patients with structural causes. The presence of trigeminal sensory deficits, bilateral involvement, and abnormal trigeminal reflexes should be considered useful to disclose symptomatic TN, whereas younger age of onset, involvement of the first division, unresponsiveness to treatment and abnormal trigeminal evoked potentials are not useful in distinguishing symptomatic from classic TN. Carbamazepine (stronger evidence) or oxcarbazepine (better tolerability) should be offered as first-line treatment for pain control. For patients with TN refractory to medical therapy early surgical therapy may be considered. Gasserian ganglion percutaneous techniques, gamma knife and microvascular decompression may be considered. Microvascular decompression may be considered over other surgical techniques to provide the longest duration of pain freedom. The role of surgery versus pharmacotherapy in the management of TN in patients with multiple sclerosis remains uncertain.

Our objective was to observe and document cardiovascular side effects of radiofrequency thermocoagulation of the trigeminal ganglion. Forty-eight patients with primary trigeminal neuralgia were enrolled into this study. Continuous electrocardiogram, heart rate, cardiac rhythm changes, and systemic blood pressure were monitored during the procedure of oval foramen puncture, electrode needle stimulation, and lesion production. Oval foramen puncture led to decreases in heart rate in 6 patients, increases in heart rate in another 42 patients, and significant elevation of mean arterial blood pressure in all 48 patients. The frequency (50 Hz) of prelesion electrical stimulation caused slight pressor responses, and radiofrequency thermocoagulation caused marked pressor responses. The correlation between the intensity of the stimulus and the magnitude of the pressor response was positive when temperature during radiofrequency thermocoagulation was below 75 degrees C. That correlation became negative when the temperature exceeded 75 degrees C. We conclude that greater anticipatory awareness should be directed toward pressor than depressor responses during the procedures of percutaneous radiofrequency thermocoagulation therapy in primary trigeminal neuralgia.

Objective: Balloon compression of the rootlets behind the trigeminal ganglion for the treatment of trigeminal neuralgia has become an increasingly popular method among neurosurgeons. However, the method has recognized complications, including double vision. Although occurring infrequently, diplopia may cause the patient significant disability. To minimize the risk for this complication, we analyzed our patients with respect to the surgical technique., Methods: We reviewed our joint consecutive series of 193 patients with trigeminal neuralgia treated with balloon compression. The medical records and the intraoperative x-ray images were analyzed., Results: We identified six patients with double vision postoperatively. In analyzing these occurrences, we found that the balloon was inflated outside Meckel's cave in four patients, the balloon was initially inflated too deeply in one patient, and the anatomy of Meckel's cave was probably aberrant in one patient. In five of the six patients, the symptoms resolved within 5 months., Conclusion: By meticulous surgical technique with close attention to the anatomic position and the shape of the inflated balloon, most cases of postcompression diplopia should be avoided.

Case Report: A 79-year-old man with severe trigeminal neuralgia presented to the pain clinic, and was offered a radiofrequency trigeminal ganglion lesion. He had only partial response to the first procedure, so a second was undertaken. The following day he presented with signs of meningitis and the diagnosis was confirmed on lumbar puncture. He was treated with appropriate antibiotics, and recovered well., Literature Review: The current literature on reports of meningitis after percutaneous trigeminal ganglion lesioning reveals an overall mean incidence of meningitis of 0.15% (confidence interval 0.10-0.21). The Scottish Intercollegiate Guidelines Network guide the decision on the routine use of antimicrobial prophylaxis, and although the risk of infection can be estimated from the literature and the severity of infection is high, the effectiveness and consequences of prophylaxis cannot be established., Conclusion: If breach of the oral mucosa has occurred, then antibiotic prophylaxis should be administered.

We aim to evaluate the mechanisms responsible for complications during trigeminal rhizotomy via foramen ovale puncture. Ten dry skulls and 10 skull-base specimens were investigated in the present study. In cadaveric skull-base specimens, the anatomical relationships between the foramen ovale, mandibular nerve and Gasserian ganglion and the surrounding neurovascular structures were investigated intradurally. The distance between the foramen ovale and Gasserian ganglion was measured as 6 mm. The abducent nerve, adjacent to the anterior tail of the petrolingual ligament, was observed passing along the lateral wall of the cavernous sinus. Advancement of the catheter more than 10 mm from the foramen ovale is likely to damage the internal carotid artery and the abducent nerve at the medial side of the petrolingual ligament. Thermocoagulation of the lateral wall of the cavernous sinus may damage the cranial nerves by heat, giving rise to pareses.

Objective: Isolated amyloidomas rarely manifest in nervous system tissues. To the authors' knowledge, there have been 52 documented cases of primary amyloid tumors of the central nervous system and closely associated structures. The authors present a case of a woman with a history of presumptive trigeminal neuralgia who was found to have an amyloidoma of the trigeminal ganglion., Clinical Presentation: A 32-year-old Caucasian patient presented with a chief complaint of severe numbness and pain throughout the right side of her face. Her symptoms had been progressive over the previous 3 years. Medical management of her presumptive diseases with Zoloft (Pfizer Inc., New York, NY) and Neurontin (Pfizer Inc.) failed to improve or halt her right facial numbness and pain. Brain magnetic resonance imaging was acquired, demonstrating abnormal contrast enhancement and enlargement of the right trigeminal ganglion. The lesion abutted and indented the right internal carotid artery and extended from Meckel's cave into the inferior cavernous sinus and distally to the foramen ovale., Intervention: The patient underwent a right frontotemporal craniotomy for resection of the gasserian ganglion lesion. A delicate incision was made in the wall of the cavernous sinus, allowing confirmatory biopsy of the lesion. With the site of the tumor within the cavernous sinus verified by pathology, the remainder of the tumor was removed. A final pathological review of the resected tumor confirmed a diagnosis of amyloidoma of the trigeminal ganglion., Conclusion: We present the case of a patient with a rare trigeminal ganglion amyloidoma that closely mimicked idiopathic trigeminal neuralgia. Even in the absence of systemic signs of amyloidosis, this benign protein deposition disease should be considered in the differential for atypical dysesthesias of the trigeminal dermatomes. Furthermore, central and peripheral nervous system amyloidomas respond well to surgical resection and rarely recur.

Idiopathic trigeminal neuralgia (ITN) is a chronic neuropathic pain that affects the masticatory system. The objective of this study was to identify orofacial pain and temporomandibular characteristics, including temporomandibular disorder (TMD), in a sample of 105 ITN patients treated with compression of the trigeminal ganglion. The evaluations occurred before, 7, 30 (1 month), 120 (3 months) and 210 days (7 months) after surgery. The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), the Clinical Questionnaire (EDOF-HC) and Helkimo Indexes were used. Findings before neurosurgery were used as control for parameters. McNemar test and variance analysis for repetitive measurements were used for statistical analysis; 45.3% of the edentulous patients presented severe dental occlusion index; numbness was an important masticatory complaint in 42.6%; mastication became bilateral, but its discomfort continued during all period; headache and body pain reduced after surgery; TMD, present in 43.8% before surgery, increased but normalized after 7 months; jaw mobility compromise was still present, but daily activities improved after 7 months. We concluded that: (i) ITN relief reduced headache, body pain, depression and unspecific symptoms; and (ii) TMD before surgery and at 7 months suggests that this may be a contributory factor to patients' pain complaints.

Background: Idiopathic trigeminal neuralgia (ITN) is often treated with balloon compression, considered in the literature to be a safer and more efficient procedure than other surgeries, with a high success rate., Methods: This study evaluated 105 patients with idiopathic trigeminal neuralgia who underwent balloon compression of the trigeminal ganglion, with a follow-up of 210 days, and clinical questionnaires and a systematic physical evaluation used as instruments., Results: There was a significant decrease in the shock-like complaint (P < .001), although 66.3% still experienced pain after 7 days of surgery from other causes; 50.5% presented limitation during jaw activities. Other complaints were hearing, taste and/or smelling loss, and visual difficulties. One patient had a TMJ ankylosis and needed surgical TMJ treatment., Conclusions: Although neurosurgery in the treatment of severe ITN pain is known to provide relief and its importance is recognized, there may also be severe complications that could compromise habitual tasks to various degrees. Therefore, the patient needs to be alerted about all complaints that he or she might present after the procedure. The professional has a duty to correctly inform and alert every patient under his or her care.

Background: The history of the development of current available techniques to treat TN was reviewed., Methods: The largest peer-reviewed publications on the surgical treatment of refractory TN were analyzed, considering the pros and cons of each technique. Results of modern peer-reviewed radiosurgery series were presented, taking into consideration the approach of each research article. Radiation doses and targets for radiosurgery were discussed to maximize the understanding of this technique., Results: It is concluded that radiosurgery is the least invasive modality with the fewest side effects, although, to match the results of the competing techniques, a substantial number of patients still need some medication intake., Conclusion: Further studies determining the ideal target and radiation dose may bring radiosurgery results to the level of the ones achieved with microvascular decompression, currently considered the gold-standard method.

Background: Percutaneous radiofrequency thermocoagulation of the trigeminal ganglion (PRTTG) is regarded as the first choice for most patients with trigeminal neuralgia (TN) because of its safety and feasibility. However, neuronavigator-guided PRTTG has been seldom reported. The purpose of this study was to assess the safety and efficacy of neuronavigator-guided PRTTG for the treatment of intractable TN., Methods: Between January 2000 and December 2004, 54 patients with intractable TN were enrolled into this study and were randomly divided into two groups. The patients in navigation group (n = 26) underwent PRTTG with frameless neuronavigation, and those in control group (n = 28) received PRTTG without neuronavigation. Three months after the operation, the efficacy, side effects, and complications of the surgery were recorded. The patients in the control group were followed up for 10 to 54 months (mean, 34 +/- 5), and those in the navigation group were followed up for 13 to 58 months (mean, 36 +/- 7). Kaplan-Meier analyses of the pain-free survival curves were used for the censored survival data, and the log-rank test was used to compare survival curves of the two groups., Results: The immediate complete pain-relief rate of the navigation group was 100%, whereas it was 95% in the control. The proportion of sustained pain-relief rates at 12, 24 and 36 months after the procedure were 85%, 77%, and 62% in the navigation group, and 54%, 40%, and 35% in the control. Recurrences in the control group were more common than that in the navigation group. Annual recurrence rate in the first and second years were 15% and 23% in the navigation group, and 46%, 60% in the control group. No side-effect and complication was noted in the navigation group except minimal facial hypesthesia., Conclusion: Neuronavigator-guided PRTTG is a safe and promising method for treatment of intractable TN with better short- and long-term outcomes and lower complication rate than PRTTG without neuronavigation.

Background: Trigeminal neuralgia is a common cause of facial pain, characterized by shock-like pain affecting one or more branches of the trigeminal nerve. When conservative treatment fails and microdecompression is not indicated, percutaneous procedures are helpful. This percutaneous approach is done by a puncture up to the Gasserian ganglion, through the foramen ovale. Although simple and safe, this puncture demands some expertise from neurosurgeons. For that, a partnership between neurosurgeons and bio-engineers has developed a model for foramen ovale puncture, allowing practice for residents and young neurosurgeons., Method: A model for foramen ovale puncture has been created by interposition of synthetic materials over a skull, simulating the human face., Findings: This model has shown great similarity with that found in conventional surgeries, even upon repeated testing by experienced functional neurosurgeons and young residents., Conclusion: This model for foramen ovale puncture training has demonstrated valuable help for initial practicing of this common neurosurgical procedure, particularly in centers where there are not many cadavers available for training.

Purpose: To learn if peripheral nerve pathways are necessary for corneal expansion and anterior segment growth under a 12-hr light:dark cycle or for the inhibition of corneal expansion under constant light rearing., Methods: Recently hatched White Leghorn chicks under anesthesia received unilateral ciliary ganglionectomy (CGx), cranial cervical ganglionectomy (Sx), or section of the ophthalmic nerve (TGx), along with sham-operated and/or never-operated control cohorts. Chicks were reared postoperatively under either a 12-hr light:dark cycle or under constant light. After 2 weeks and with the chicks under anesthesia, corneal radii of curvature and diameters were obtained with a photokeratoscope, refractometry and A-scan ultrasonography were performed, and the axial and equatorial dimensions of enucleated eyes were measured with digital calipers. Corneal areas were calculated from corneal curvatures and diameters., Results: Despite the rich peripheral innervation to the eye, the selective denervations performed here exerted remarkably limited effects on corneal expansion and anterior segment development in chicks reared under either lighting condition. Ophthalmic nerve section did reverse in large part the inhibition of equatorial expansion of the vitreous chamber occurring under constant light rearing., Conclusions: The ciliary, sympathetic, or ophthalmic peripheral nerve pathways to the eye are not required either for corneal expansion and anterior segment development under a 12-hr light:dark cycle or for the inhibition of corneal expansion under constant light rearing. The ocular sensory innervation may be a means for regulating vitreous cavity shape.

Purpose: To investigate the hypothesis that sensory denervation of the rabbit lacrimal gland results in dysregulation of protein synthesis. We used differential display of mRNA to identify genes associated with protein synthesis and secretion that may be altered in this situation., Methods: New Zealand white rabbits underwent unilateral sensory denervation by the ablation of the trigeminal ganglion. After 7 days, the denervated and contralateral control lacrimal glands were removed. The effects of denervation on gene expression were carried out using differential mRNA display. Northern and Western blot analyses were used to verify differential gene expression., Results: Differential mRNA display identified the gene heme-regulated inhibitor eukaryotic initiation factor-2 alpha kinase (HRI eIF-2a kinase) in the lacrimal gland, the expression of which was reduced in the denervated lacrimal gland. The sequenced fragment from differential display showed 94% identity to rabbit HRI eIF-2a kinase. The decreased expression of HRI eIF-2a kinase was confirmed by Northern and Western blots, and measurement of HRI eIF-2a kinase phosphorylation activity in the lacrimal gland after ablation of sensory neurons showed that it was significantly decreased compared with that of normal and control lacrimal glands., Conclusions: The results suggest that loss of sensory innervation has a role in the lacrimal gland, contributing to the expression of HRI eIF-2a kinase, a pivotal negative regulator of protein synthesis. A reduction in control of protein synthesis may lead to the translation of repressed messages associated with cell stress responses.

Background: We present the experience in the treatment of trigeminal neuralgia (TN) during 15 years in one institute, evaluating epidemiological variables and clinical presentation, and comparing the results obtained with different treatments available., Methods: A retrospective, descriptive study was carried out by reviewing cases diagnosed by the Neurology Service, such as TN, and treated by the Pain Medicine and Palliative Care Unit of the Insituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubíran," from January 1, 1998 to December 31, 2003. Age, sex, type of neuralgia, anatomical site affected and intensity of pain were evaluated by means of the Analogue Visual Scale (AVS). The following treatments were evaluated (pharmacologic, surgical, and blockade of Gasser ganglion). Descriptive statistics, linear regression and bivariate correlation were used (statistical package SPSS)., Results: Fifty two cases were studied with a female predominance (2:1). Average age was 60 years. Clinical presentation most frequently was typical neuralgia (51.9%), right predominance (59.6%) and affected branch V2 (50%). In 88%, pharmacological treatment was used. The reduction of pain was 74% in all cases, with r-.765 for the pharmacological treatment, r-.715 in the blockade of the Gasser ganglion, and r-.901 for surgical treatment (p < 0.01)., Conclusions: In the experience of the INCMNSZ, treatment of choice in most cases of TN is pharmacological, with surgical treatment useful in cases where vascular alterations were identified.

The case of a 68 year-old man who developed a fatal intracranial hemorrhagic complication following percutaneous compression of the gasserian ganglion for trigeminal neuralgia is reported. The complication was likely related to improper placement of the Fogarty catheter into the temporal fossa out of the Meckel's cave. The anatomical structures at risk of damage by misplaced needle or catheter and some relevant technical details aimed to prevent extratrigeminal complications related with this and other percutaneous trigeminal lesioning procedures are analyzed.

The denervation and/or the removal of peripheral nerve ganglia are useful surgical techniques for studying the source and distribution of peripheral nerves in all organs, including the eye. The amount and distribution of the remaining nerve fibres supplying the eye (after sectioning of various types of nervous fibres and/or removal of nerve ganglia) were evaluated in the rat. Male Sprague-Dawley rats were anaesthetized and one or more of the following nervous tissues were removed: superior cervical ganglion, main ciliary ganglion, pterygopalatine ganglion, trigeminal ganglion and the ophthalmic-maxillary nerve. In some animals, chemical sympathectomy was performed by administration of 6-OH dopamine. The eyes were cut in serial sections, but only three regions (cornea, iris and choroid) were harvested and submitted for various nerve fibre staining techniques. The results were quantified and statistically analysed. Superior cervical ganglionectomy and/or chemical sympathectomy induced the destruction of almost all the catecholaminergic nerve fibres in the three examined regions of the rat eye. Removal of the ciliary ganglion (partial parasympathectomy) caused the destruction of about 60% of the cholinergic nerve fibres of the same regions of the rat eye, while subtotal parasympathectomy destroyed about 80% of the cholinergic nerve fibres. Surgical transsection of the ophthalmo-maxillary nerve or the removal of the trigeminal ganglion led to a degeneration of almost all sensitive nerve fibres of the three examined regions of the rat eye. The denervation experiments confirmed the presence of the different types of nerve fibres (sympathetic, parasympathetic and sensitive) in the three studied structures of the rat eye.

Neurotrophic keratopathy (NK), a consequence of sensory denervation of the cornea, must be better understood in order to develop new approaches to therapy. The purpose of this study was to create a rat model for neurotrophic keratopathy by denervating the trigeminal nerve through a ventral approach with stereotaxic surgery. Stereotaxic coordinates were measured in 46 male Sprague Dawley rat cadavers for localization of V1. After further refining the coordinates in nine live animals, radiofrequency ablation was chosen as an effective method of disrupting the innervation to the cornea. Fifty-two live rats were treated with radiofrequency ablation to define the anatomical localization of the lesion by utilizing gross and histopathological studies. A gross lesion of the trigeminal nerve and/or ganglion was observed in 47 (90%) of the 52 animals. Histopathological studies revealed that all 52 animals had anatomical damage of the trigeminal innervation to the eye. Low mortality and little morbidity were observed in these animals. We have developed a rat model for neurotrophic keratopathy that is simple to produce, accurate in creating a lesion by utilizing stereotaxic techniques combined with radiofrequency ablation, and successful in decreasing morbidity and mortality.

Posttraumatic headache is a common and disabling pain syndrome in patients who sustain a head injury. Unfortunately, conventional treatments may fail or cause intolerable side effects. Because chronic headache may be mediated by central and peripheral neural processes, these structures may be therapeutic targets. One target, the sphenopalatine ganglion (SPG), is implicated in several headache disorders and has been lesioned for headache relief. Because of the risks of neurolytic procedures, nonablative procedures that provide pain relief would be useful. We present a case wherein a man in his late twenties with posttraumatic headache obtained more than 17 months of relief with SPG pulsed-mode radiofrequency lesioning. SPG pulsed-mode radiofrequency is a nonablative, neural lesioning method that may be useful in the treatment of posttraumatic headache.

Objective: There are no randomized controlled trials comparing retrogasserian percutaneous radiofrequency thermocoagulation, glycerol rhizolysis, balloon compression of the gasserian ganglion, and stereotactic radiosurgery, nor are there systematic reviews using predefined quality criteria. The objective of this study was to systematically identify all of the studies reporting outcomes and complications of ablative techniques for treatment of trigeminal neuralgia, from the development of electronic databases, and to evaluate them with predefined quality criteria., Methods: Inclusion criteria for the outcome analysis included thorough demographic documentation, defined diagnostic and outcome criteria, a minimum of 30 patients treated and median/mean follow-up times of 12 months, not more than 20% of patients lost to follow-up monitoring, Kaplan-Meier actuarial analysis of individual procedures, less than 10% of patients retreated because of failure or early recurrence, and a minimal dose of 70 Gy for stereotactic radiosurgery. High-quality studies with no actuarial analysis were used for the evaluation of complications., Results: Of 175 studies identified, 9 could be used to evaluate rates of complete pain relief on a yearly basis and 22 could be used to evaluate complications. In mixed series, radiofrequency thermocoagulation offered higher rates of complete pain relief, compared with glycerol rhizolysis and stereotactic radiosurgery, although it demonstrated the greatest number of complications., Conclusion: Radiofrequency thermocoagulation offers the highest rates of complete pain relief, although further data on balloon microcompression are required. It is essential that uniform outcome measures and actuarial methods be universally adopted for the reporting of surgical results. Randomized controlled trials are required to reliably evaluate new surgical techniques.

The etiology of trigeminal neuralgia appears to be vascular compression of the nerve at the root entry zone. However, the physiologic mechanism of trigeminal neuralgia remains uncertain. To gain insight into the pathophysiology of the disorder, we developed a method for intraoperative microneurographic recordings from the trigeminal ganglion of patients with trigeminal neuralgia. The recordings are performed immediately prior to standard percutaneous trigeminal gangliolysis for pain relief. Spontaneous or evoked single- and multi-unit action potential activity can be recorded and the location of receptive fields determined. The method should facilitate the testing of hypotheses concerning the origin of this unique pain disorder.

Idiopathic trigeminal neuralgia (ITN), (tic dou-loureux), may be defined as a chronic painfull disorder of the sensory divisions of the trigeminal nerve, with unexplained cause and pathogenesis. The clinical features are characterized by recurrent paroxysmal lancinating pain confined to distribution of one or more branches of the nerve. Radiofrequency rhizotomy (RFR) of ganglion Gasseri is a methode of choise in treatment of ITN. We present the series of 1600 patients suffering from ITN who underwent RFR between 1984 and 2001. Ages ranged from 29 to 88 years, with a mean age of 62 years. Total pain relief immediately after a single radiofrequency lesion was achieved in 1469 (92%) of patients. After one year a recurrence of pain was present in 145 (10%). Age, sex and duration of illness were unrelated to outcome. Patients previously treated by open surgery appeared to receive less benefit from subsequent RFR. Clinical outcome correlated with the degree of sensory deficit created by RFR. Patients acquiring dense deficit demonstrated a reduced risk of recurrence: 203/1129 (18%) of patients with dense sensory loss and 75/258 (29%) of those with a partial deficit developed a recurrence by three years, whereas almost all patients (78/82) without initial sensory loss suffered a recurrence by three years. Serious complications resulting from RFR were infrequent and the most common was the permanent dysesthesia in 9 (0.6%) of patients. Our results suggest that the RFR is an well bearable and effective longterm surgical treatment for ITN, especially for older and poor-risk patients.

This investigation evaluates the results of percutaneous trigeminal ganglion compression (PTGC) and compares them those for microvascular decompression (MVD) in treating trigeminal neuralgia. The authors report 127 cases of trigeminal neuralgia treated by PTGC and comparing the results with those of 114 patients whom underwent MVD from 1985 to 2000. The following parameters were compared: technical success, pain relief and recurrence, complications, perioperative morbidity, and perioperative mortality. PTGC and MVD initially had similar initial success rates. However, MVD had a higher rate of pain recurrence at the first 2 years follow-up, as well as higher rates of major complications and perioperative morbidity. Meanwhile, PTGC had higher rates of facial numbness, dysesthesia and minor complications.

Because intraoral capsaicin is reported to reduce the perceived intensity of certain taste qualities, we investigated whether it affects the central processing of gustatory information. The responses of gustatory neurons in the nucleus tractus solitarius (NTS) to tastant stimuli were recorded before and after lingual application of capsaicin in anesthetized rats. Thirty-four NTS units were characterized as responding best to sucrose (0.3 m), NaCl (0.1 m), citric acid (0.03 m), monosodium glutamate (0.2 m), or quinine (0.001 m). During lingual application of 330 microm capsaicin for 7 min, the firing rate increased for five units and decreased for four units; the remainder were unaffected. Immediately after capsaicin, responses to each tastant were in nearly all cases depressed (mean, 61.5% of control), followed by recovery in most cases. NTS tastant-evoked unit responses were unaffected by lingual application of vehicle (5% ethanol). Capsaicin elicited an equivalent reduction (to 64.5%) in tastant-evoked responses of nine additional NTS units recorded in rats with bilateral trigeminal ganglionectomy, arguing against a trigeminally mediated central effect. Furthermore, capsaicin elicited a puncate pattern of plasma extravasation in the tongue that matched the distribution of fungiform papillae. These results support a peripheral site of capsaicin suppression of taste possibly via direct or indirect effects on taste transduction or taste receptor cell excitability. The depressant effect of capsaicin on gustatory transmission might underlie its ability to reduce the perceived intensity of some taste qualities.

Trigeminal neuralgia is a type of facial pain that is difficult to treat. The pain can be excruciating and debilitating. The wide range of treatments currently used for trigeminal neuralgia is ample evidence that there is no simple answer to how it should be managed. This review will evaluate the current surgical procedures used for the treatment of trigeminal neuralgia. A critical analysis of the evidence-based studies to date was done to evaluate and compare the efficacy of the different surgical procedures. Arguments for and against the use of surgery for trigeminal neuralgia are presented. In addition, the surgical procedures were compared with other treatments for trigeminal neuralgia.

Cellular schwannomas rarely involve the cranial nerves, being more common in the spinal and peripheral nerves. A rare case of cellular schwannoma involving the gasserian ganglion, a hitherto unreported site, that extended infratentorially to present as a cerebellopontine angle tumor is reported. It is important to recognize that cellular schwannomas can histologically mimic malignant peripheral nerve sheath tumors because of their high cellularity and mitotic activity, but they are relatively benign tumors with a tendency to recur but not metastasize.

Idiopathic trigeminal sensory neuropathy is a clinically benign disorder in which the main feature is facial numbness limited to the territory of one or more divisions of the trigeminal nerve; the disorder persists for a few weeks to several years. and no underlying disease can be identified. Magnetic resonance (MR) imaging findings are occasionally consistent with a small trigeminal neuroma of the left gasserian ganglion associated with idiopathic trigeminal sensory neuropathy. The authors report on two patients who were treated using a skull base approach in which the gasserian ganglion was exposed and the lesion was removed. The pathological diagnosis was chronic granulomatous neuritis. The authors conclude that, in patients with MR findings suggestive of a small trigeminal neuroma, benign idiopathic trigeminal sensory neuropathy should also be considered in the differential diagnosis. A conservative approach featuring sequential MR imaging studies may avoid an unnecessary surgical exploration.

Percutaneous trigeminal ganglion compression for the relief of trigeminal neuralgia is a technically simple, non-painful procedure, carried out under brief general anesthesia. The patients could tolerate well during the treatment. The operation successful rate is high, and the procedure can be repeated at the next day if the symptom was not relieved. The procedure, in the present, is the first choice for those trigeminal neuralgia patients who are poor medical risks, those who are above the age of 65, those with demyelinating disease, and those who are unwilling to accept the increased risk of a posterior fossa craniectomy. We have successfully performed this procedure for two recurrent trigeminal neuralgia patients without any surgical complication. We propose this surgical treatment algorithm for trigeminal neuralgia patients who are not able to tolerate the medical treatment.

Trigeminal neuralgia is the most frequent cranial neuralgia, the incidence being 1 per 1,000,00 persons per year. It presents with stabbing pain often in the distribution of the mandibular and maxillary divisions of the trigeminal nerve. An accurate history of pain is important in the diagnosis of trigeminal neuralgia. A patient with tic douloureux and no neurological abnormality on clinical examination does not need diagnostic tests. The available options for management of trigeminal neuralgia are: Pharmacotherapy, destructive procedures and non-destructive procedures. The pharmacotherapy includes (i) monotherapy with one anticonvulsant, (ii) combined therapy with more than one anticonvulsant, (iii) add-on therapy with newer drugs and (iv) polytherapy with anticonvulsant + add-on drugs + antidepressants/anxiolytics. Destructive procedures include (i) non-surgical methods--injections along trigeminal pathways, percutaneous trigeminal radiofrequency thermocoagulation and (ii) surgical methods--trigeminal branch avulsion or peripheral neurectomy, avulsion of trigeminal nerve, trigeminal tractotomy, radiosurgery. Though various modalities of treatment are available for the management of trigeminal neuralgia, pharmacotherapy with carbamazepine still remains the first line of treatment. The alternative approach followed at most centres is percuatenous Gasserian rhizolysis (chemical/radiofrequency thermal) or microvascular decompression.

Therapy: Nowadays the theory of microvascular compression of the root entry zone of trigeminal nerve in case of trigeminal neuralgia is widely accepted. Pathological contacts between a-beta fibers and c-fibers are believed to be caused by an arterial compression in the root entry zone. It is these ephaptic contacts that have led to a logical therapeutic sequence of treatment by means of membrane stabilising agents like anticonvulsant drugs as carbamazepine, nonablative - and, in view of the pathophysiological concept, causal - surgery in form of microvascular decompression described by Jannetta and ablative operative methods, which are restricted to certain well-defined indications., Additional Procedures: Other and additional surgical procedures are of use only in cases of atypical facial pain or with therapy non-responders. Methods like Caudalis-DREZ-Lesion and specific techniques such as cervical superior ganglion infiltration with opioids are worth being mentioned.

In the researches of the innervation relationship between trigeminal ganglion and a particular structure in the head, it is usually necessary to apply neural tracers into the ganglion for anterograde nerve tracing study or perform bilateral trigeminal nerve transecting for degeneration study. A common surgical approach for exposing these structures in the rat was to remove a piece of skull and a portion of brain. While investigating the innervation of rat's pineal gland from its trigeminal ganglion, we used a subtemporal fossa approach, whereby the mortality of the animal was remarkably reduced and the contamination of the intracranial structures by the tracer was proved to be least. This is the first description of bilateral surgeries of the trigeminal ganglion and trigeminal nerve in rat using extracranial approach. Detailed surgical procedures were presented and their advantages discussed.

In order to establish that the pineal gland is innervated by pituitary adenylate cyclase-activating polypeptide (PACAP)-immunoreactive nerve fibers originating in the trigeminal ganglion, ophthalmic and maxillary nerves were transected by using a subtemporal fossa approach. The number of PACAP-immunoreactive nerve fibers in the pineal gland of rats with a total transection of the nerve was compared with that of rats without surgery. In the operated rat, PACAP-immunoreactive nerve fibers in the superficial pineal decreased remarkably, indicating that the trigeminal ganglion was the origin of these nerve fibers. This research provides evidence supporting the hypothesis that PACAP-immunoreactive nerves regulate the synthesis and/or secretion of melatonin in the pineal gland.

In a 25-year-old woman with episodic periorbital-temporal pain who eventually developed a sixth nerve palsy, magnetic resonance imaging revealed a lesion predominantly in the Meckel cave that was found to be a capillary hemangioma arising from the mandibular division of the trigeminal nerve. Hemangiomas of the Meckel cave must be considered in cases of facial pain with a sixth nerve palsy. even if there are no clinical findings of trigeminal neuropathy.

Background: Amyloidoma in the central nervous system is extremely rare. We describe a rare case of amyloidoma in the gasserian ganglion manifesting as trigeminal neuropathy., Methods: A 41-year-old woman was admitted to our hospital with progressive numbness and hypalgesia in the distribution of the second and third divisions of the left trigeminal nerve. There was no evidence of chronic inflammatory disorder or immunological abnormalities. Magnetic resonance images showed a mass in the left Meckel's cave that was brightly enhanced with gadolinium., Results: A reddish, firm mass was successfully removed via a left temporal craniotomy. Histologically, the tumor was composed of larger acellular deposits of eosinophilic material. The acellular deposits were positive for potassium permanganate-resistant Congo red staining, showing apple-green birefringence under polarized light and expression of immunoglobulin lambda light chain-derived proteins (A lambda) immunohistochemically., Conclusion: The present case revealed an A lambda amyloidoma in the left gasserian ganglion. Although the incidence is rare, amyloidoma should be suspected in patients who complain of progressive trigeminal neuropathies and show an enhanced lesion in the gasserian ganglion on MR images.

Objective and Importance: Idiopathic inflammatory trigeminal sensory neuropathy (IITSN) is a disorder with the dominant clinical features of trigeminal sensory disturbance; this idiopathic condition follows a benign course in most cases. Recent reports have shown that transient abnormalities, which may mimic those of trigeminal neuromas, can be observed in magnetic resonance imaging scans. Presented here is a case of IITSN that was diagnosed, with cytological and histopathological verification, during the active inflammatory phase of the disease (the first such attempt, to our knowledge)., Clinical Presentation: A 20-year-old female patient was referred to our hospital with a 2-month history of numbness of the left side of her face, headache, and hemifacial pain attacks. Cranial magnetic resonance imaging scans revealed a mass above and below the foramen ovale, extending into the cavernous sinus., Intervention: A percutaneous biopsy procedure through the foramen ovale was performed; the pathological examination revealed lymphocytes, macrophages, and endothelial cells but no evidence of neoplastic cells. A few days later, the patient was surgically treated using a cranial base approach, the gasserian ganglion was exposed, and the lesion was removed. Pathological examination of the specimens revealed inflammatory changes and fibrosis of the nerve fibers and ganglion cells. Disruption of the myelin around the nerve bundles was detected. Therefore, IITSN was pathologically confirmed during the early stage of the disease. During 3 months of follow-up monitoring, the patient experienced no serious clinical problems., Conclusion: IITSN should be suspected in cases of tumors involving the cavernous sinus, and a percutaneous biopsy through the foramen ovale should be performed as part of the differential diagnosis in such cases. This procedure might obviate unnecessary aggressive surgery. In the current case, no neoplastic cells were observed during the examination; only lymphocytes, macrophages, and endothelial cells were observed, on a background of erythrocytes. Lymphocyte-dominant inflammatory infiltration, fibrotic changes, and demyelinization are cardinal histopathological findings observed during the active phase of IITSN.

Hypothesis: The middle fossa (MF) approach is undergoing a marked resurgence in vestibular schwannoma surgery as a hearing conservation technique. It is widely recognized that the extradural temporal lobe retractors used in this procedure, despite their cleverness of design, could be improved., Methods: To identify the characteristics of an ideal MF retractor, a systematic analysis of the safety and functionality of four commonly used retractors (House-Urban, Fisch, Garcia-Ibanez, and UCSF) in a human anatomical model was conducted. Intensity of temporal lobe compression, width of exposure, angle of visualization, obstruction to instrument access, ergonomic convenience of use, and adaptability to other subtemporal procedures (e.g. lesions of Meckel's cave and cavernous sinus) were quantified., Results: Because the intracranial portions of the retractors are similar, the force transmitted to the brain differed little among the four retractors. Numerous differences were noted in the ergonomics of use and versatility of the various designs., Conclusions: The optimal MF retractor would incorporate the best features of each of the existing systems: the integral suction of the Garcia-Ibanez, the bone contour-following design of the Fisch retractor base, the unobtrusiveness and adaptability of the UCSF, and the three-plane adjustability of the vintage House-Urban. Evolution of an "ideal" MF retractor requires further technical refinements and the development of an experimental model of extradural brain retraction to assess the optimal strategy for obtaining exposure while minimizing the risk for temporal lobe injury.

Objective: The aim of the present study is to examine the operative technique and results of the treatment of trigeminal neuralgia (TN) by percutaneous microcompression of the trigeminal ganglion (Mullan's technique) in 20 consecutive patients over 3 years., Patients and Methods: The average age of the patients was 63 years. There were 8 men and 12 women. The operative technique is similar to Mullan and Lichtor's original description with some modifications., Results: On average it takes 30 minutes to complete the procedure. On 2 occasions the catheter had to be replaced as the balloon burst without clinical repercussions. Detectable changes were noted in systemic blood pressure and cardiac rhythm in 10 cases. On 17 occasions the radiographic appearance of the balloon was pear-shaped and in the remaining cases it was oval or irregular. Follow-up ranged from 6 months to 3 years. All but 1 patient were initially relieved of pain and it was progressively possible to suspend treatment with carbamazepine. The recurrence rate was 25%. Mean time until recurrence was 18 months. There was no relation between pain location and recurrence. Morbidity: some degree of transient cheek discomfort, herpes simplex perioralis, hypesthesia and masseter weakness were the rule. Meningitis in one case., Conclusions: Early results indicate that Mullan's technique provides a reliable, safe, cheap and effective, with low morbidity and no mortality.

Background: Mechanisms of the surgical treatment of trigeminal neuralgia are considered., Results: Trigeminal neuralgia is effectively treated by microvascular decompression (MVD) and other surgical procedures. These procedures often cause reactivation of herpes simplex virus (HSV), which is latent in trigeminal ganglion neurons., Conclusion: MVD and other surgical procedures alter ganglion neuron transcription, as indicated by HSV reactivation. Controlled injury of the trigeminal root-ganglion probably occurs with the disparate surgical procedures, and this is likely the means of their effectiveness.

The effect of this axotomy on the expression of vasoactive intestinal polypeptide (VIP) in trigeminal ganglion neurones and nerve fibres in the first molar was examined immunohistochemically 3 weeks postsurgically in rats. A distinct upregulation of VIP-like immunoreactivity was found in 3 to 4% of the neurones (mean dia., 20.9 +/- 0.45 microns; mean cross-sectional area, 367 +/- 13.2 microns 2) in the mandibular region after axotomy. An almost complete coexpression was registered in neurones upregulated for VIP and growth-associated protein 43. Coexpression of VIP and substance P (SP) was found in a small number of the immunoreactive (IR) small-sized neurones, mainly in those in which VIP and SP were both weakly immunoreactive. In the uninjured ganglion, weakly labelled VIP-positive granules were frequently traced at high magnification in the cytoplasm of small neurones. No VIP-IR fibres were found in the control molar pulp, except for a few in the root pulp near the apex. However, 3 weeks after axotomy, a number of VIP-containing nerve fibres were found in the molar pulp and apical periodontium. Coarse VIP-IR fibres directed towards the odontoblast layer were a common finding. In some of these fibres VIP was shown to colocalize with SP. These results indicate that VIP is clearly expressed and transported in regenerating primary afferent neurones after axotomy of the inferior alveolar nerve.

The petrolingual ligament is the posteroinferior attachment of the lateral wall of the cavernous sinus, where the internal carotid artery enters the cavernous sinus. The petrous segment of the internal carotid artery finishes and the cavernous segment begins at the superior margin of this ligament. The ligament is surgically important due to its identification as a landmark for dissection of the internal carotid artery during the approaches to posterolateral intracavernous and extracavernous lesions. It can be well exposed after mobilization of the gasserian ganglion, or after the trigeminal root and ganglion have been split along the junction of V2 and V3 (the transtrigeminal approach). The petrolingual ligament was studied in five cadaveric head specimens from ten sides. The size of the ligament was measured, and its anatomical, clinical and surgical importance is discussed.

The results of treating 61 patients suffering from trigeminal neuralgia by Gasserian ganglioglycerolysis were estimated in the studies. The following features were considered: sex, age, side of pain, duration of symptoms, pharmacological therapy and the course glycerolysis procedure, with attention being paid to whether the CSF outflow is present or not. The ganglionglycerolysis procedure was modified to ensure that the needle is inserted directly in the ganglion, but not into periganglional space. The anesthetic effect was obtained by simultaneous glycerol injection and slow needle withdrawal. The recent and remote results were assessed by implementing own subjective pain sensibility scale, characterizing the therapeutic results and the frequency of disease recurrence.