Trigeminal Neuralgia In Multiple Sclerosis Research Articles

Trigeminal neuralgia in multiple sclerosis: Association with demyelination and progression.

Trigeminal neuralgia (TN) is a well-recognized symptom of multiple sclerosis (MS), yet its clinical characteristics related to MS subtype is poorly studied. Our aim was to evaluate whether development and clinical outcome of TN are influenced by MS phenotype. In this retrospective cohort study, our database from 2007 to 2022 was reviewed to identify patients who had both the diagnosis of MS and TN, whether TN was an initial symptom of MS or developed later in diagnosis. A detailed medical history and treatment outcome was obtained. Pain status was assessed retrospectively using the Barrow Neurological Institute Pain Scale (BNI-PS), with BNI-PS I-III considered as good pain control and BNI-PS IV-V as poor pain control. 58 patients had MS-related TN. 44 patients had relapsing remitting multiple sclerosis (RRMS) at the time of TN diagnosis, 11 had secondary progressive multiple sclerosis (SPMS) at the time of TN diagnosis, and type of MS was not clear in 3 patients at the time of TN diagnosis (either RRMS or SPMS). Over a mean follow up of 18.8 (SD=10.9) years, 30 transitioned to SPMS. TN was refractory to medical management in 9 RRMS and 22 SPMS patients (p=0.001). TN patients with RRMS required lower median number of pain medications compared to SPMS (p=0.014). Brain MRI was available in 41 of the entire cohort. Of these, 27 patients had demyelinating lesions in the trigeminal sensory pathway and 14 did not. Patients with existing lesions had a higher chance of failure of medical management (74% versus 36%, p=0.017) and required surgical intervention (55% versus 7%, p=0.003). TN was not seen in primary progressive multiple sclerosis (PPMS). In patients who transitioned to SPMS, TN was more likely to be refractory to medical management. TN was more refractory in the presence of demyelinating plaque involving trigeminal sensory pathway.

Operative findings and outcome of microvascular decompression/adhesiolysis for trigeminal neuralgia in multiple sclerosis without demyelinating brain stem lesions

ObjectiveTrigeminal neuralgia (TN) in multiple sclerosis (MS) poses several challenges for treatment. Although these patients often have typical attacks, they may not be considered as candidates for microvascular decompression (MVD). Here we report on surgical findings and long term follow-up of MVD/ adhesiolysis in a series of patients with multiple sclerosis but without demyelinating brain stem lesions. MethodsFifteen patients with MS-related TN underwent MVD/ adhesiolysis. Demyelinating brain stem lesions were excluded radiologically. Outcome of the intervention was assessed according to the Barrow Neurological Institute (BNI) pain intensity score at 3, 12, 24 months follow-up and at the last available follow-up (mean 88.2 months, range 38–146). ResultsAll 15 patients benefited from MVD/adhesiolysis and were pain free on the first day of surgery. Intraoperative findings included arterial contact in 7/15 (47 %) patients, venous contact in 9/15 (60 %), and prominent arachnoid thickening in 12/15 (80 %). The distribution of the BNI pain intensity scores showed marked improvement at all follow-up evaluations. Five patients underwent repeat MVD/adhesiolysis for pain recurrence at a mean of 43 months after the first surgery. Long term evaluation at the last available follow-up demonstrated favorable outcome in 13/15 patients (BNI I-IIIa) (87 %), while 2/15 patients had limited benefit (BNI IV). ConclusionsMS-related TN in patients without demyelinating brain stem lesions may be related either to vascular conflicts or to focal arachnoiditis at the trigeminal nerve entry zone. MVD/ adhesiolysis may be considered as a useful treatment option in this subgroup of patients with regard to long term outcome.

Trigeminal interfascicular neurolysis (nerve combing) for refractory recurrent neuralgia in multiple sclerosis.

In multiple sclerosis (MS) patients, trigeminal neuralgia (TN) represents a challenging syndrome to treat, often refractory to medical therapy and percutaneous techniques. Despite the frequent lack of a neurovascular conflict, the trigeminal nerve’s axons are often damaged, with the myelin sheath permanently degenerated, thus explaining the difficulty in treating TN in MS.The authors illustrate trigeminal interfascicular neurolysis (the combing technique) to control refractory recurrent TN in MS: the nerve is longitudinally divided along its fibers from the root entry zone, determining good pain relief.The video can be found here: https://youtu.be/o1XksPW5fMY

Comparison of Stereotactic Radiosurgery and Radiofrequency Ablation for Trigeminal Neuralgia in Multiple Sclerosis Patients

Background: The optimal treatment for medically refractory trigeminal neuralgia in multiple sclerosis (MS-TN) patients is unknown. Objective: To compare treatment outcomes between stereotactic radiosurgery (SRS) and radiofrequency ablation (RFA). Methods: We performed a retrospective study of MS-TN patients treated with SRS or RFA between 2002 and 2019. Outcomes included degree of pain relief, pain recurrence, and sensory changes, segregated based on initial treatment, final treatment following retreatment with the same modality, and crossover patients. Results: Sixty surgical cases for 42 MS-TN patients were reviewed. Initial pain freedom outcomes and rates of retreatment were similar (SRS: 30%; RFA: 42%). RFA resulted in faster onset of pain freedom (RFA: <1 week; SRS: 15 weeks; p < 0.001). SRS patients with pain relief had longer intervals to pain recurrence at 2 years (p = 0.044). Final treatment outcomes favored RFA for pain freedom/off-medication outcomes (RFA: 44%; SRS: 11%; p = 0.031), though RFA resulted in more paresthesia (RFA: 81%; SRS: 39%; p = 0.012). Both provided at least 80% of adequate pain relief. Crossover patients did not have improved pain relief. Conclusions: SRS and RFA are both valid surgical options for MS-TN. Discussion with providers will need to balance patient preference with their unique treatment characteristics.

Trigeminal neuralgia in multiple sclerosis: Prevalence and association with demyelination.

The association of trigeminal neuralgia (TN) with multiple sclerosis (MS) is still widely unaddressed in larger, systematical clinical series. In this study, a cohort of Finnish MS patients was assessed regarding the incidence and prevalence of TN, as well as the presence of demyelinating lesions near the trigeminal ganglion, thus searching for a causative role of MS plaques in TN onset. All consecutive patients treated and followed up for MS (ICD-code G35) in Helsinki University Hospital during 2004-2017 were identified from the Finnish MS register. A hospital administrative database search was used to identify all patients treated and followed up for TN during the same period. Among the MS patients, head MRI scans available from the diagnostic phase of TN or thereafter were analysed. We identified a total of 2575 patients with MS and 2008 patients with TN. Both diagnoses could be verified for 55 patients, giving a prevalence of 2.1% for TN in MS. The incidence of TN in MS patients was 149/100000 person-years (95% CI 108-190). In the general outpatient population of our neurological department, the incidence of TN was 9.9/100000 person-years (95% CI 9.5-10.3). A demyelinating lesion in the proximity of the trigeminal ganglia was seen for 63% of the 41 patients with relevant MRI data available. Incidence of TN among MS patients was 15-fold higher than in the general neurological outpatient population, thus in favour of a strong association between MS and TN.

The Effectiveness of Percutaneous Balloon Compression, Thermocoagulation, and Glycerol Rhizolysis for Trigeminal Neuralgia in Multiple Sclerosis

Balloon compression (BC), thermocoagulation (TC), and glycerol rhizolysis (GR) are percutaneous surgical options for trigeminal neuralgia (TN). Whether the outcomes of these procedures in multiple sclerosis -related TN (MS-TN) are as effective as in idiopathic TN (ITN) is unknown. To retrospectively compare pain relief, complications, and durability achieved by these 3 types of procedures in MS-TN and ITN. Two hundred and four patients with typical TN were treated percutaneously: 33 had MS-TN (64 procedures) and 171 had ITN (329 procedures). All were performed by 1 of 2 neurosurgeons; interviews enabled long-term data to be gathered by an independent observer. MS-TN patients (53.1%) had Barrow Neurological Institute pain scores of I or II after a percutaneous procedure, compared with 59.3% in the ITN cohort; there was no difference in initial relief between the 2 groups overall (P=.52). There was a trend toward fewer complications in MS-TN compared with ITN (23.4% vs 33.7%, respectively; P=.058). Kaplan-Meier analysis demonstrated no difference in durability of relief in MS-TN (median 23.0 mo) compared with ITN overall (median 24.0 mo; P=.75). Subgroup analysis demonstrated longer relief from BC and TC compared with GR in MS-TN (P=.013). Multivariate analysis confirmed that although the presence of MS does not predict durability of outcome, postoperative numbness (P=.0046) and undergoing a repeat procedure (P=.037) were significant predictors. BC and TC are safe and effective in MS-TN. Postoperative numbness is the strongest prognostic factor in MS-TN.

Supratentorial lesions contribute to trigeminal neuralgia in multiple sclerosis.

Background It has been proposed that multiple sclerosis lesions afflicting the pontine trigeminal afferents contribute to trigeminal neuralgia in multiple sclerosis. So far, there are no imaging studies that have evaluated interactions between supratentorial lesions and trigeminal neuralgia in multiple sclerosis patients. Methods We conducted a retrospective study and sought multiple sclerosis patients with trigeminal neuralgia and controls in a local database. Multiple sclerosis lesions were manually outlined and transformed into stereotaxic space. We determined the lesion overlap and performed a voxel-wise subtraction analysis. Secondly, we conducted a voxel-wise non-parametric analysis using the Liebermeister test. Results From 12,210 multiple sclerosis patient records screened, we identified 41 patients with trigeminal neuralgia. The voxel-wise subtraction analysis yielded associations between trigeminal neuralgia and multiple sclerosis lesions in the pontine trigeminal afferents, as well as larger supratentorial lesion clusters in the contralateral insula and hippocampus. The non-parametric statistical analysis using the Liebermeister test yielded similar areas to be associated with multiple sclerosis-related trigeminal neuralgia. Conclusions Our study confirms previous data on associations between multiple sclerosis-related trigeminal neuralgia and pontine lesions, and showed for the first time an association with lesions in the insular region, a region involved in pain processing and endogenous pain modulation.

Stereotactic radio surgery and radio frequency rhizotomy for trigeminal neuralgia in multiple sclerosis: A single institution experience

ObjectivesFor patients with medically unresponsive trigeminal neuralgia (TN), surgical options include micro vascular decompression (MVD), radiofrequency rhizotomy (RF), and stereotactic radio surgery (SRS). Multiple sclerosis (MS) is a demyelinating condition that can be associated with TN, but is not amenable to treatment with MVD. We sought to identify the outcome differences of patients with TN in MS undergoing SRS or RFR in an attempt to identify factors that may influence outcomes. We also evaluated cost outcomes, both initially and over time, based on the index procedure. We performed a retrospective review of our experience with 17 cases. Patients and methodsA single institution retrospective chart review was performed. Since 1997, 17 patients with TN and MS have been treated at our institution. All patients underwent a preoperative MRI to rule out a compressive lesion. Patients either underwent SRS (n=7) or RFR (n=10) as their index procedure and were evaluated as a group based on this first procedure. Outcome measures included preoperative Expand Disability Status Score (EDSS) scores, pre- and postoperative facial pain and medication use, post-intervention facial numbness, need for subsequent procedures, and duration of follow-up. Charges for the index procedure, subsequent interventions, and total costs were tabulated and analyzed in 2017 US dollars, adjusting for inflation. ResultsThe median age of patients at first operation in each group was 58.5±10.9 and 63.5±7.5 for SRS and RFR respectively. There were no significant differences in basic demographics. Overall, 71% of these patients had an excellent or good initial pain outcome. Over time, 60% of RFR and 29% of SRS patients required additional procedures to obtain satisfactory pain relief. The patients who underwent RFR as their index procedure required a significantly higher number of procedures to achieve adequate pain relief (RFR=2.7 vs SRS=2.0 [p=0.04]). The average index procedure costs in US dollars were significantly different (SRS=53,300±5257 vs RFR=12,315±3387). The average subsequent costs (costs incurred following the initial intervention) (SRS=8320±17,842, RFR=36,002±46,767) and total costs (SRS=61,620±16,087, RFR=48,317±48,475) were not statistically significantly different. ConclusionTN in the setting of MS is highly difficult to treat medically with SRS and RFR being offered as options for these patients. Both can provide good initial pain relief. For patients who have RFR as their initial procedure, a larger number of procedures are required for relief compared to patients who initially underwent SRS. While there is a significant difference in the cost of the initial procedure, over time, with the cost of required subsequent interventions, there is no significant difference in total costs between the two groups.

Trigeminal Neuralgia Commonly Precedes the Diagnosis of Multiple Sclerosis.

Trigeminal neuralgia (TN) is a well-recognized cause of facial pain in the general population, and multiple sclerosis (MS) accounts for some of these cases. However, the prevalence of TN in MS is poorly understood. We investigated the prevalence of TN and how often TN is the initial presentation of MS in a large MS cohort. In 2009, we surveyed participants in the North America Research Committee on Multiple Sclerosis Registry regarding TN, including date of onset and pharmacologic and nonpharmacologic treatments used. We estimated the frequency of TN and the frequency with which TN preceded the diagnosis of MS. We compared the demographic and clinical characteristics of participants who reported TN with those of participants who did not using descriptive statistics and logistic regression. Among 8590 eligible survey respondents, the prevalence of TN was 830 (9.7%). Of these respondents, 588 reported the year when TN was diagnosed. The diagnosis of TN preceded that of MS in 88 respondents (15.0%), and the mean ± SD age at diagnosis of TN was 45.3 ± 11.0 years. The odds of reporting TN were higher in women and those with greater disability and longer disease duration. Pharmacologic treatments were used by 88.3% of respondents; 9.7% underwent surgical interventions. In MS, TN occurs frequently and precedes the diagnosis of MS in 15.0% of individuals. Given the frequency of TN in MS, further epidemiological studies and clinical trials to identify effective pharmacologic and nonpharmacologic therapies for TN in MS are warranted.

Comparison of Percutaneous Retrogasserian Balloon Compression and Gamma Knife Radiosurgery for the Treatment of Trigeminal Neuralgia in Multiple Sclerosis

We compared and evaluated percutaneous retrogasserian balloon compression (PBC) and Gamma Knife radiosurgery (GKRS) for treatment of trigeminal neuralgia (TN) in patients with multiple sclerosis (MS). In this single-center, retrospective comparative study, 202 patients with MS and concomitant TN were evaluated. A minimum follow-up of 24 months was required. Patients with a history of microvascular decompression or previous intervention were excluded. Between February 2009 and December 2013, 78 PBC procedures and 124 first-dosage GKRS procedures were performed. PBC procedures were successfully completed in all cases. The 2 groups were compared with regard to initial effect, duration of effect, and complications including type and severity. Immediate pain relief occurred in 87% of patients treated with PBC and in 23% of patients treated with GKRS. Kaplan-Meier plots for the 2 treatment modalities were similar. The 50% recurrence rate was at 12 months for the PBC group and 18 months for the GKRS group. Complication (excluding numbness) rates were 3% for GKRS and 21% for PBC. The difference was statistically significant (χ2 test, P= 0.03). PBC and GKRS are effective techniques for treatment of TN in patients with MS. Fewer complications and superior long-term relief were associated with GKRS. We consider GKRS as the first option for the treatment of TN in patients with MS, reserving PBC for patients with acute, intractable pain.

Minimally Invasive Surgical Treatment of Intractable Trigeminal Neuralgia in Multiple Sclerosis

Background: Retrograssean balloon compression of the trigeminal nerve is a common treatment modality used for the treatment of trigeminal neuralgia in patients without multiple sclerosis (MS), but is not commonly used in patients diagnosed with MS, where the facial pain is a result of scar tissue or demyelinating plaques. Approximately 10 percent of patients with MS have a diagnosis of trigeminal neuralgia (TN). Most patients develop other symptoms of multiple sclerosis and optic neuritis before the facial pain and the diagnosis of MS is usually established before they develop chronic facial pain. These patients are more likely to develop the symptoms on both sides of the face than those without MS, but rarely anyone has both sides of the face are affected at the same time. This cases report an efficient method to treat an acute episode of intractable trigeminal neuralgia in multiple sclerosis patients. Case Description: We report the cases of two women with a primary diagnosis of MS that presented with secondary trigeminal neuralgia. The patients were 38 and 56 years old. Patients presented to the ER with pain that was described as a “shooting” sensation in the V1-V2 and V3 distributions, with an intensity of 10/10, and not relieved by pharmacologic or Radiosurgical treatment. Both cases were treated by retrograssian balloon compression by neuro-navigation based on the difficulty to foramen ovale puncture. Conclusion: The treatment of TN in patients with MS presents a dilemma. The difficulty of demyelinating disease is identifying the source of pain and finding the best treatment for the symptoms. This is the primary challenge for neurosurgeons in treating MS patients with atypical facial pain. Micro vascular decompression should not be considered as primary treatment of trigeminal neuralgia in this patient population, where the target plate and not the neurovascular conflict related trigeminal neuralgia. Stereotactic Radiosurgery can be a good treatment option, but there is a lack of published data to support the treatment in acute setting after failure of treatment by Radiosurgery. Retrograssean balloon compression by neuro-navigation could be a successfully rescue technique in acute complex trigeminal neuralgia in MS patient.

Diffusion tensor imaging of the trigeminal nerve in patients with trigeminal neuralgia due to multiple sclerosis.

Neurovascular compression (NVC) is the most common cause of trigeminal neuralgia (TN), leading to microstructural changes in the affected nerve detectable using diffusion tensor imaging (DTI). But TN may also emerge as a symptom of multiple sclerosis (MS). The aim of this study was to evaluate if patients with MS-related TN feature the same DTI characteristics as patients with TN caused by NVC. Twelve patients with MS-related TN, 12 age-matched patients with NVC-related TN, and 12 healthy controls were included. Using 3T-DTI, mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated for each affected and contralateral trigeminal nerve in patients with MS and NVC-related TN as well as healthy controls. Furthermore, presence of NVC was evaluated for patients with TN. There was no significant difference concerning FA or ADC when comparing the affected and the non-affected sides in patients with MS. FA was significantly lower and ADC higher in patients with MS on the TN affected as well as on the non-affected side compared to the non-affected side of patients with idiopathic TN or healthy controls. Likewise, FA was significantly lower on the affected side compared to the non-affected side in patients with idiopathic TN or healthy controls. NVC was evident in 41.7/0% on the affected/contralateral side in MS patients and 100/8% in the patients with NVC-related TN. In patients with MS-related TN, DTI reveals microstructural changes within the trigeminal nerve not only on the affected side but also on the clinically non-affected side.

Glycerol rhizotomy and radiofrequency thermocoagulation for trigeminal neuralgia in multiple sclerosis

Patients with trigeminal neuralgia due to multiple sclerosis (TN-MS) and idiopathic TN (ITN) who underwent glycerol rhizotomy (GR) and radiofrequency thermocoagulation with glycerol rhizotomy (RFTC-GR) were compared to investigate the effectiveness of these percutaneous ablative procedures in the TN-MS population. Between 1998 and 2010, 822 patients with typical TN were evaluated; 63 (8%) had TN-MS and 759 (92%) had ITN. Pain relief comparisons were made between 22 GR procedures in patients with TN-MS and 470 GR procedures in patients with ITN; 50 RFTC-GR procedures in patients with TN-MS and 287 RFTC-GR procedures in patients with ITN were compared. Analysis of time to recurrence included only procedures that achieved complete pain relief without medications. After 15 of the GR procedures (68%) in patients with TN-MS and 315 of the procedures (67%) in those with ITN, the patients were pain free without medications (p = 0.736). After 36 of the RFTC-GR procedures (72%) in patients with TN-MS and 210 of the procedures (73%) in those with ITN, the patients were pain free without medications (p = 0.657). The difference in pain relief between GR and RFTC-GR for patients with TN-MS was not significant (p = 0.447). The median time to failure of GR was 20 months in patients with TN-MS compared with 25 months in those with ITN (p = 0.403). The median time to failure of RFTC-GR was 26 months in the TN-MS population compared with 21 months in the ITN population (p = 0.449). Patients with TN-MS experienced similar times to recurrence whether they were treated with GR or RFTC-GR (p = 0.431). Pain relief and durability of relief outcomes of GR and RFTC-GR were similar in patients with TN-MS and ITN, reinforcing their use as preferred treatments of TN-MS. The GR and RFTC-GR achieved comparable outcomes in patients with TN-MS, suggesting that both can be used to good effect.

Trigeminal neuralgia in multiple sclerosis patients: a clinical comparison of trigeminal neuralgia in patients with and without underlying multiple sclerosis

Background: The prevalence of trigeminal neuralgia (TN) is higher in multiple sclerosis (MS) as compared in the general population. Clinical and treatment responses of MS patients compared with non-MS patients are in debate. Objective: To evaluate clinical differences in trigeminal pain presentation and pharmacological treatment response in patients with and without underlying MS. Material and methods: A retrospective study of 10 MS patients that had TN as a first symptom or in the MS course (from the total 545 MS patients). Data regarding MS (sex, age at MS onset, type, symptomatology, number and site of lesions on brain MRI, treatment) and TN (clinical characteristics of facial pain, treatment), period from TN as a clinically isolated syndrome to defined MS or period from MS onset to TN beginning were analyzed. Clinical, demographical and treatment response were compared with corresponding data of 10 consecutive patients hospitalized for idiopathic TN. Results: The only difference between MS and non-MS patients was the age of onset of TN (41.8 ±6.12 in MS vs 52.7±16.5 in non –MS patients, p=0.07, unpaired Student’s t-test). There are no differences in trigeminal pain characteristics between MS and non-MS patients. Conclusions: TN among MS patients has an onset at younger age but share the same pain characteristics and treatment responds with TN in the general population. TN in MS has multiple mechanisms of aetiopathogenesis and surgical treatment must be held in mind in selected cases.

Prevalence of migraine, tension‐type headache and trigeminal neuralgia in multiple sclerosis

Prevalence rates of headache in multiple sclerosis (MS) patients varied widely in recent studies. This study aimed to investigate the 1 year prevalence of headache in MS compared with the general population. Population-based case-control study in Germany. We included 491 patients with definite MS (68% female, mean age 45.3 years, 63.7% relapsing remitting MS, mean Expanded Disability Status Scale (EDSS) 3.2, 106 treated with interferon-beta, 53 with glatiramer acetate, 271 untreated) and 447 age and gender matched controls. Headache was diagnosed with a validated questionnaire according to the International Headache Society Criteria. Headache prevalence was 56.2% (tension type headache 37.2%, migraine 24.6%). Headache prevalence rates did not differ from controls. Headache was not associated with disability or treatment. Trigeminal neuralgia was found in 6.3% of MS cases. Results suggest that headache in MS patients reflects comorbidity in most conditions.

Validity of percutaneous controlled radiofrequency thermocoagulation in the treatment of isolated third division trigeminal neuralgia

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.

Some patients with multiple sclerosis have neurovascular compression causing their trigeminal neuralgia and can be treated effectively with MVD: Report of five cases

The role of trigeminal ganglion percutaneous injection and radio-frequency lesioning procedures for the treatment of trigeminal neuralgia (TGN) in multiple sclerosis (MS) is well established. There is general acceptance that microvascular decompression (MVD) cannot be an appropriate treatment due to the view that the underlying aetiology is a demyelinating plaque affecting the root entry zone of the trigeminal pathway. Recently, MR-imaging has been used in the preoperative investigation of this group of patients demonstrating that neurovascular compression can occasionally be the responsible mechanism and that MVD can be the treatment of choice. We present five cases with MS and TGN. All the patients had failed to respond to medical treatment or percutaneous procedures. Magnetic resonance imaging demonstrated evidence of neurovascular compression in four cases. All the patients underwent MVD. Postoperatively four of the five patients made an uncomplicated recovery, were pain-free and fully satisfied with the result (mean follow-up 38.75 months; range 8 – 59 months). One patient developed recurrent pain 1 week following surgery and went on to have a total sensory rhizotomy. TGN in MS can be caused by neurovascular compression, which may be identified on MR-imaging. MVD has offered satisfactory short-term outcome for at least 2 years and does not inflict sensory loss. Longer follow-up will determine whether the outcome in MS patients will be as successful as in the TGN patients who do not suffer from MS.

Central pain in multiple sclerosis – prevalence and clinical characteristics

Pain is more common in multiple sclerosis (MS) than has previously been recognised. In the present study we have investigated the occurrence of central pain (CP) in MS and defined its characteristics. Questionnaires were sent to all 429 patients with definite MS in the patient register at our neurology department. All admitting to pain were interviewed and offered an extended interview and examination. Three hundred and sixty four patients responded (86%), of whom 57.5% reported pain during the course of their disease (21% nociceptive, 2% peripheral neuropathic and 1% related to spasticity). One hundred patients (27.5%) had CP, including 18 patients (4.9%) with trigeminal neuralgia. The non-trigeminal CP was, in 87%, located in the lower and in 31% in the upper extremities. It was mostly bilateral (76%) and constant, with 88% experiencing daily pain. Only 2% had paroxysmal attacks. Aching, burning, pricking were the commonest qualities. The pain was intense with small to moderate spontaneous variation. In 5.5% of all patients (20% of the patients with CP), pain was a presenting symptom, alone or in combination with other symptoms. The most common neurological symptoms/signs besides CP were sensory abnormalities (98%, dominated by abnormal sensibility to painful stimulus and temperature). Trigeminal neuralgia in MS started later in life and after longer disease duration than non-trigeminal pain. Both types of CP existed either chronically or as a feature of relapse. Central pain is thus an important symptom in MS (around 30%) and causes much suffering.

Gamma knife radiosurgery for trigeminal neuralgia associated with multiple sclerosis

Object. The authors assessed the efficacy and complications from gamma knife radiosurgery (GKS) for multiple sclerosis (MS)-associated trigeminal neuralgia (TN). Methods. There were 15 patients with MS-associated TN (MS—TN). Treatment involved three sequential protocols, 70 to 90-Gy maximum dose, using a single 4-mm isocenter targeting the ipsilateral trigeminal nerve at its junction with the pons with the 50% isodose. Pain was appraised by each patient by using Barrow Neurological Institute (BNI) Scores I through IV: I, no pain; II, occasional pain not requiring medication; IIIa, no pain but continued medication; IIIb, some pain, controlled with medication; IV, some pain, not controlled with medication; and V, severe pain/no pain relief. With a mean follow up of 17 months (range 6–38 months), 12 (80%) of 15 patients experienced pain relief. Three patients (20%) reported no relief (BNI Score V). For responders, the mean latency from treatment to the onset of pain relief was 13 days (range 1–61 days). Maximal relief was achieved after a mean latency of 56 days (range 1–157 days). Five patients underwent a second GKS after a mean interval of 534 days (range 231–946 days). The mean maximum dose at this second treatment was 48 Gy. The target was unchanged from the first treatment. All five patients who underwent repeated GKS improved. Complications were limited to delayed facial hypesthesias. Two (13%) of 15 patients experienced onset of numbness after the first GKS, as well as two of five patients following a second GKS. The patients found this mild and not bothersome. Each patient who developed hypesthesias also experienced complete pain relief. Conclusions. Gamma knife radiosurgery is an effective treatment for MS—TN. Radiosurgery carries an acceptable small risk of mild facial hypesthesias, and hypesthesia appears predictive of a favorable outcome.

Choice of open or percutaneous procedures in the surgical treatment of trigeminal neuralgia

The aim of this study was to define criteria for the selection of patients for percutaneous or open operations for the cure of drug-resistant trigeminal neuralgia (TN). Trigeminal percutaneous radiofrequency thermorhizotomy (TPRT) has an established place because of its safety in elderly patients, while microvascular decompression (MVD) has appeal in younger patients beause of its non-destructive nature and because it attacks what is believed to be the primary etiology of tic douloureux.Nevertheless, MVD is a successful operation only when true neurovascular conflict (NVC) is ascertained, rather than a simple arterial loop and neurovascular contract. Probably, many immediate failures and early relapses are the consequence of the inadequate patient selection for MVD on the presumption that this operation is in any case the ideal cure. The inadequate selection can be explained by the difficult preoperative diagnosis of NVC in the past. Indeed, angiography and computed tomography showed the neurovascular contact but not the size of compression. Fortunately, today magnetic resonance imaging is a reliable instrument to ascertain NVC. So, the diatribe between the supporters of percutaneous techniques and MVD can be concluded with the following: (1) percutaenous techniques are indicated for patients without demonstrated NVC (including patients with TN in multiple sclerosis) and in those with NVC if MVD is contraindicated by ill-health or refused by the informed patient; and (2) MVD is incated for patients with ascertained NVC who are in good health and who, informed of the surgical risk, favor this operation desiring no sensory deficit.