Facial Pain Outcomes Research Articles

Facial pain and sensory outcomes following resection of tumors compressing the trigeminal nerve.

Tumors compressing the trigeminal nerve can cause facial pain, numbness, or paresthesias. Limited data exist describing how these symptoms change after resection and what factors predict symptom improvement. The objective of this study was to report trigeminal pain and sensory outcomes after tumor resection and identify factors predicting postoperative symptom improvement. This retrospective study included patients with tumors causing facial pain, numbness, or paresthesias who underwent resection. Trigeminal schwannomas were excluded. Logistic regression, recursive partitioning, and time-to-event analyses were used to report outcomes and identify variables associated with facial sensory outcomes. Eighty-six patients met inclusion criteria, and the median follow-up was 3.1 years; 63 patients (73%) had meningiomas and 23 (27%) had vestibular schwannomas (VSs). Meningioma patients presented with pain, numbness, and paresthesias in 56%, 76%, and 25% of cases, respectively, compared with 9%, 91%, and 39%, respectively, for patients with VS. Most meningioma patients had symptoms for less than 1 year (60%), whereas the majority of VS patients had symptoms for 1-5 years (59%). The median meningioma and VS diameters were 3.0 and 3.4 cm, respectively. For patients with meningiomas, gross-total resection (GTR) was achieved in 27% of patients, near-total resection (NTR) in 29%, and subtotal resection (STR) in 44%. For patients with VS, GTR was achieved in 9%, NTR in 30%, and STR in 61%. Pain improved immediately after tumor resection in 81% of patients and in 92% of patients by 6 weeks. Paresthesias improved immediately in 80% of patients, increasing to 84% by 6 weeks. Numbness improved more slowly, with 52% of patients improving immediately, increasing to 79% by 2 years. Pain recurred in 22% of patients with meningiomas and 0% of patients with VSs. After resection, the Barrow Neurological Institute (BNI) facial pain intensity score improved in 73% of patients. The tumor diameter significantly predicted improvement in BNI score (OR 0.47/cm larger, 95% CI 0.22-0.99; p = 0.047). Complete decompression of the trigeminal nerve was associated with qualitative improvement in pain (p = 0.037) and decreased pain recurrence (OR 0.08, 95% CI 0.01-0.67; p = 0.024). Most patients with facial sensory symptoms caused by meningiomas or VSs experienced improvement after resection. Surgery led to immediate and sustained improvement in pain and paresthesias, whereas numbness was slower to improve. Patients with smaller tumors and complete decompression of the trigeminal nerve were more likely to experience improvement in facial pain.

Prospective Comparison of Redo Microvascular Decompression and Percutaneous Balloon Compression as Primary Surgery for Recurrent Trigeminal Neuralgia.

ObjectiveTo prospectively compare facial pain outcomes for patients having either a repeat microvascular decompression (MVD) or percutaneous balloon compression (PBC) as their surgery for trigeminal neuralgia (TN) recurrence. MethodsProspective cohort study of 110 patients with TN recurrence who had either redo MVD (n=68) or PBC (n=42) from July 2010 until September 2016. The mean follow-up was 45.6 months. ResultsAfter redo MVD, 65 patients (95.6%) experienced immediate relief of pain. After PBC, 34 patients (81%) were immediately relieved of their neuralgia. After 1 month, the clinical effect of redo MVD was better than PBC (p<0.01). Patients who had redo MVD more commonly were pain free off medications (93.4% at 1 year, 78.2% at 4 years) compared with the PBC patients (85.1% at 1 year, 59.3% at 4 years). However, mean length of stay was longer (p>0.05). Patients after PBC who occurred developed herpes simplex (35.7%), facial numbness (76.2%), and annoying dysesthesia (21.4%) more frequently compared with patients after redo MVD who occurred developed herpes simplex (14.7%), facial numbness (8.8%), and hypoesthesia (5.9%) (p<0.05). The symptoms recurred respectively in 15 patients (22.1%) and 19 patients (45.2%) after redo MVD and PBC within the entire 6-year follow-up period. ConclusionFor the patients with TN recurrence, redo MVD was a more effective procedure than PBC. The cure rate and immediate relief of pain were better, and the incidence of complications was lower.

Orthognathic surgery in the presence of temporomandibular dysfunction: what happens next?

One of the most well-known yet perhaps controversial conditions affecting temporomandibular dysfunction (TMD) and the signs and symptoms of facial pain and clinical outcomes after orthognathic surgery procedures is temporomandibular joint internal derangement. This article provides an overview of the mutual relationship between orthognathic surgery and TMD, with especial consideration to internal derangement. The existing literature is reviewed and analyzed and the pertinent findings are summarized. The objective is to guide oral and maxillofacial surgeons in their clinical decision making when contemplating orthognathic surgery in patients with preexisting TMD.

Salvage Gamma Knife Radiosurgery after failed management of bilateral trigeminal neuralgia.

Background:The incidence of bilateral trigeminal neuralgia (TN) is 1-6% of total number of TN cases. Gamma Knife Radiosurgery (GKRS) is effective in treating unilateral TN; however, outcomes of bilateral TN treated by GKRS have not been well evaluated. The purpose of this study is to evaluate the long-term GKRS outcomes of bilateral TN at our institution and compare with our published treatment outcomes of unilateral TN.Methods:Between 2000 and 2006, eight patients with bilateral TN were treated with GKRS. Data available on seven patients were collected. Facial pain outcomes were defined using the Barrow Neurological Institute pain intensity scale. Outcomes and toxicities were compared to published outcomes of unilateral TN patients treated with GKRS at our institution.Results:The incidence of bilateral TN in our series is 2.3%. Treatment outcomes were excellent in 5/14, good in 1/14, and poor in 8/14. Median follow-up time was 58 months. Median time-to-failure was 38 months. Pain control rate was 80% at 12 months and 65% at 36 months. Bothersome side effects were seen in 4/14 nerves treated. Compared with our long-term unilateral TN cohort, there was no statistically significant difference in outcome, time-to-failure, or rate of toxicity.Conclusion:Bilateral TN is rare, and effective treatment is crucial to improve the quality of life of those afflicted. Salvage GKRS is a reasonable treatment modality for individuals with bilateral TN.

Outcomes After Percutaneous Surgery for Patients With Multiple Sclerosis-Related Trigeminal Neuralgia

Approximately 1% to 2% of patients with multiple sclerosis (MS) develop trigeminal neuralgia (TN). Percutaneous surgery is commonly performed in medically refractory cases. To analyze the pain outcomes and complications of patients with MS-related trigeminal neuralgia (MS-TN) having percutaneous surgery. Patients having balloon microcompression (BMC; n = 69) or glycerol rhizotomy (PRGR; n = 67) from 1997 to 2010 were reviewed retrospectively. Patients in the 2 groups were similar with regard to age, sex, pain location, and pain quality. Mean pain duration was longer in the PRGR group (54.6 vs 16 months; P < .001); more patients having BMC had prior surgery (87% vs. 48%; P < .001). Outcomes were defined as excellent (no pain, no medications), good (no pain with medications), and poor. Median follow-up was 13 months (range, 0.25-132 months). Ninety-five patients initially had excellent (n = 45, 33%) or good (n = 50, 37%) outcomes. Pain relief was maintained in 58% of patients at 3 months and 28% at 2 years. There was no difference in excellent/good outcomes between the surgical groups (hazard ratio = 0.73; P = .14). No correlation was noted between pain relief and new or increased facial numbness (hazard ratio = 0.78; P = .19). Forty-four BMC patients (64%) had additional surgery compared with 36 PRGR patients (54%; P = .19). Complications were more frequent after BMC (17.4% vs 3.0%; P < .01). Percutaneous surgery for patients with MS-TN is less likely to provide pain relief than similar operations performed for patients with idiopathic TN. New trigeminal deficits did not correlate with better facial pain outcomes, supporting the concept that many patients with MS-TN have centrally mediated pain.

Posterior Fossa Exploration for Trigeminal Neuralgia Patients Older Than 70 Years of Age

Patients with medically unresponsive trigeminal neuralgia (TN) who are >70 years of age often undergo operations that typically provide pain relief for <5 years despite having a life expectancy that can exceed 15 years. To review the safety and efficacy of posterior fossa exploration (PFE) for TN patients > 70 years of age. From 1999 to 2009, 67 TN patients >70 years of age (median, 74 years) underwent a PFE. Thirty-seven patients (55%) had failed ≥ 1 prior surgeries (median, 2). Fifty-nine patients (88%) had a microvascular decompression, and 8 patients (12%) underwent a partial sensory rhizotomy. Follow-up (median, 40 months) was censored at the time of last contact (n = 51), additional surgery (n = 12), or death (n = 4). Complete pain relief (no pain, no medications) was 87% at 1 year and 78% at 5 years. Facial pain outcomes did not correlate with patient age, sex, prior surgery, or pain duration. Postoperative complications were noted in 10 patients (15%) and included ataxia (10%), hearing loss (5%), trigeminal dysesthesias (5%), facial weakness (3%), aseptic meningitis (2%), and pulmonary embolus (2%). Factors associated with postoperative complications were prior PFE (P = .01) and neurovascular compression from a dolicoectatic basilar artery (P = .03). Posterior fossa exploration is safe and effective for physiologically healthy TN patients >70 years of age. It should be deferred in older patients with TN secondary to a dolicoectatic basilar artery and patients who have persistent/recurrent pain after a previous PFE unless simpler procedures prove ineffective at controlling their facial pain.

Prospective Comparison of Posterior Fossa Exploration and Stereotactic Radiosurgery Dorsal Root Entry Zone Target as Primary Surgery for Patients With Idiopathic Trigeminal Neuralgia

Trigeminal neuralgia (TN) is the most common facial pain syndrome, with an incidence of approximately 27 per 100,000 patient-years. To prospectively compare facial pain outcomes for patients having either a posterior fossa exploration (PFE) or stereotactic radiosurgery (SRS) as their first surgery for idiopathic TN. Prospective cohort study of 140 patients with idiopathic TN who had either PFE (n = 91) or SRS (n = 49) from June 2001 until September 2007. The groups were similar with regard to sex, pain location, and pain duration. Patients who had SRS were older (67.1 vs 58.2 years; P < .001). The median follow-up after surgery was 38 months. Patients who had PFE more commonly were pain free off medications (84% at 1 year, 77% at 4 years) compared with the SRS patients (66% at 1 year, 56% at 4 years; hazard ratio = 2.5; 95% confidence interval, 1.4-4.6; P = .003). Additional surgery for persistent or recurrent face pain was performed in 14 patients after PFE (15%) compared with 17 patients after SRS (35%; P = .009). Nonbothersome facial numbness occurred more frequently in the SRS group (33% vs 18%; P = .04). No difference was noted in other complications between patients who had PFE (12%) (dysesthetic facial pain, n = 3; cerebrospinal fluid leakage, n = 3; hearing loss, n = 2; wound infection, n = 1; pneumonia, n = 1; deep vein thrombosis, n = 1) and patients who had SRS (8%) (dysesthetic facial pain, n = 4; P = .47). PFE is more effective than SRS as a primary surgical option for patients with idiopathic TN.

Retreatment of trigeminal neuralgia with Gamma Knife radiosurgery: is there an appropriate cumulative dose?

Trigeminal neuralgia (TN) is a disorder of the trigeminal nerve that results in intense episodic pain. Primary treatment with Gamma Knife surgery (GKS) is well established; however, a significant number of patients experience recurrence of TN over time. Repeat GKS can be performed, but the retreatment dose has not been well established. In this study, the authors present their institutional retreatment results and compare them with other series. Between December 2003 and January 2006, 28 patients were treated at Tufts Medical Center with repeat GKS for recurrence of TN. All patients had been initially treated with GKS at this institution, and only those with significant pain improvement were offered retreatment. The maximum dose was prescribed using a single isocenter; the 4-mm collimator was used. The initial median GKS dose was 80 Gy, the median retreatment dose was 45 Gy, and the median cumulative dose was 125 Gy. The median time between GKS procedures was 18.1 months. Facial pain outcomes were defined using the Marseille scale. Excellent outcome was defined as no pain (with or without medications), and good outcome was defined as > 50% pain relief. Toxicity was categorized as none, mild, or bothersome. The median clinical follow-up after the second GKS was 19.7 months. Our clinical outcomes were compared with 8 previously reported retreatment series (including 1 abstract), both for rate of pain control and for rate of complications. Outcomes after the second GKS were excellent in 29% (8 patients), good in 32% (9), and poor in 39% (11). Four patients (14%) experienced no improvement after repeat GKS. Eight patients (29%) experienced new trigeminal nerve dysfunction, including numbness (11%), paresthesia (14%), dysesthesia (4%), taste alteration (11%), and bite weakness (4%). None of these were bothersome. No patient developed corneal numbness. Univariate analysis failed to reveal any significant predictors of pain control or complications. Seven published peer-reviewed retreatment series and the authors' data (total 215 patients) were analyzed. There was a cumulative dose-response relationship for both pain control (p = 0.04) and new trigeminal dysfunction (p = 0.08). Successful pain control was strongly correlated with development of new dysfunction (p = 0.02). A cumulative dose > 130 Gy was more likely to result in successful (> 50%) pain control, but was also more likely (> 20%) to result in development of new dysfunction. Successful retreatment of patients in whom the initial GKS treatment fails is feasible. Patients who respond initially may be at a higher risk of retreatment-related complications. There appears to be a dose-response relationship for both pain control and development of new side effects. It is important to counsel and treat patients individually based on this dose-response relationship.

Repeat posterior fossa exploration for patients with persistent or recurrent idiopathic trigeminal neuralgia

Patients with trigeminal neuralgia (TN) and persistent or recurrent facial pain after microvascular decompression (MVD) typically undergo less invasive procedures in the hope of providing pain relief. The outcomes and risks of repeat posterior fossa exploration (PFE) for these patients are not clearly understood. From September 2000 to November 2006, 29 patients (14 men, 15 women) underwent repeat PFE. The mean number of surgeries per patient at the time of repeat PFE was 3.2 (range 1-6). The mean follow-up duration after surgery was 33.7 months. Compression of the trigeminal nerve was noted in 24 patients (83%) by an artery (13 patients, 45%), vein (4 patients, 14%), or Teflon (7 patients, 24%). Four patients (14%) who underwent operations elsewhere had incorrect cranial nerves decompressed at their first surgery. Only MVD was performed in 18 patients (62%) and a partial nerve section (PNS) was performed in 11 patients (38%). An excellent facial pain outcome (no pain, no medications required) was achieved and maintained for 80% and 75% of patients at 1 and 3 years after surgery, respectively. Patients with Burchiel Type 1 TN were pain free without medications (91% at 1 year and 85% at 3 years) more frequently than patients with Burchiel Type 2 TN (27% at both 1 and 3 years; hazard ratio = 5.4, 95% confidence interval 1.4-21.1, p = 0.02). Fifteen patients (52%) had new or increased facial numbness. Two patients (7%) developed anesthesia dolorosa; both had undergone PNS. Two patients (7%) had hearing loss after surgery. Repeat PFE for patients with idiopathic TN has facial pain outcomes that are comparable with both percutaneous needle-based techniques and stereotactic radiosurgery. Patients with persistent or recurrent TN should be considered for repeat PFE, especially if other less invasive surgeries have not relieved their facial pain.

Radiosurgery for trigeminal neuralgia: is sensory disturbance required for pain relief?

Over the past 15 years stereotactic radiosurgery has become an accepted surgical option for patients with medically unresponsive trigeminal neuralgia (TN). The mechanism whereby radiosurgery causes pain relief remains unclear. A review of recent papers on the radiosurgical management of TN reveals a correlation between maximum prescription dose and facial pain outcomes (p = 0.03) and between maximum prescription dose and new-onset trigeminal dysfunction (p < 0.01). In five of six studies in which investigators specifically analyzed whether there is any relationship between postradiosurgical trigeminal dysfunction and facial pain outcomes, there was a statistically significant greater chance of patients being pain free without medications if new trigeminal dysfunction developed after radiosurgery. Likewise, combining the results of two small series on repeated radiosurgery for TN also showed a significant correlation between postradiosurgical trigeminal dysfunction and facial pain outcomes (p = 0.02). Although the quality of data available does not permit a formal metaanalysis of radiosurgery for TN, the preponderance of information supports an association between the development of facial sensory loss and pain relief after radiosurgery. Consequently, radiosurgery should be considered a destructive technique in which the goal is similar to that in other percutaneous ablative techniques used to manage TN: create sufficient damage to the trigeminal system to achieve pain relief, but not so much injury that the patient is at risk for deafferentation pain syndromes.

A Prospective Cost-Effectiveness Study of Trigeminal Neuralgia Surgery

Approximately 8000 patients with trigeminal neuralgia undergo surgery each year in the United States at an estimated cost exceeding $100 million. We compared 3 commonly performed surgeries (microvascular decompression, glycerol rhizotomy, and stereotactic radiosurgery) to evaluate the relative cost-effectiveness of these operations for patients with idiopathic trigeminal neuralgia. Prospective nonrandomized trial at a tertiary referral center from July 1999 to December 2001. One hundred twenty-six consecutive patients underwent 153 operations (microvascular decompression, n=33; glycerol rhizotomy, n=51; stereotactic radiosurgery, n=69). Preoperative characteristics were similar between the groups with respect to sex, pain location, duration of pain, and atypical features. Facial pain outcomes were classified as excellent (no pain, no medications), good (no pain, reduced medications), fair (>50% pain reduction), and poor. The cost per quality adjusted pain-free year was compared between the groups. Mean follow-up was 20.6 months. Patients having microvascular decompression more commonly achieved and maintained an excellent outcome (85% and 78% at 6 and 24 months) compared with glycerol rhizotomy (61% and 55%, P=0.01) and stereotactic radiosurgery (60% and 52%, P<0.01). No difference was detected between glycerol rhizotomy and stereotactic radiosurgery (P=0.61). The cost per quality adjusted pain-free year was $6,342, $8,174, and $8,269 for glycerol rhizotomy, microvascular decompression, and stereotactic radiosurgery, respectively. Reduction in the average cost of morbidity and additional surgeries to zero did not make either microvascular decompression or stereotactic radiosurgery more cost-effective than glycerol rhizotomy. Both microvascular decompression and stereotactic radiosurgery would be more cost-effective than glycerol rhizotomy if the cost of additional surgeries after glycerol rhizotomy increased 79% and 83%, respectively. This analysis supports the practice of percutaneous surgeries for older patients with medically unresponsive trigeminal neuralgia. At longer follow-up intervals, microvascular decompression is predicted to be the most cost-effective surgery and should be considered the preferred operation for patients if their risk for general anesthesia is acceptable. More data are needed to assess the role that radiosurgery should play in the management of patients with trigeminal neuralgia.

Gamma Knife Radiosurgery for Trigeminal Neuralgia

The purpose of this study was to assess outcomes in patients treated with gamma knife radiosurgery for trigeminal neuralgia. From 1997 to 2003, a total of 49 patients with trigeminal neuralgia underwent gamma knife radiosurgery. The trigeminal root entry zone immediately adjacent to the pons was targeted by use of a 4-mm collimator to deliver 40 Gy to the 50% isodose line (maximum dose, 80 Gy). Special care was taken to limit radiation dose to the adjacent pons to 12 Gy. Of the 49 study patients, all had undergone previous medical therapy, 8 (16%) had undergone microvascular decompression, 8 (16%) had undergone percutaneous rhizotomy, 2 (4%) had undergone linear accelerator-based radiosurgery, and 5 (10%) presented with multiple sclerosis. The median duration of symptoms was 6 years. There were 29 female patients (59%) and 20 male patients (41%). Facial pain outcomes were assessed by use of the Barrow Neurological Institute pain score. Other outcomes assessed included recurrence of symptoms and treatment toxicity. The median follow-up period was 49 months. At last evaluation, a total of 27 patients (61%) with idiopathic trigeminal neuralgia reported pain relief (scores of IIIb or less). This included 14 patients (32%) who reported complete pain relief when not receiving medications. Significant recurrence of pain after an initial interval of relief was reported by 10 patients (23%). Mean time to pain recurrence was 9.6 months (range, 2-36 mo). Mild to moderate facial numbness was experienced by 13 patients (29%), whereas 8 (18%) reported mild dysesthesias. Gamma knife radiosurgery established durable pain relief in 61% of patients with medically refractory idiopathic trigeminal neuralgia. A longer follow-up period is necessary to fully assess the incidence of late complications and recurrences.

Comparison of posterior fossa exploration and stereotactic radiosurgery in patients with previously nonsurgically treated idiopathic trigeminal neuralgia

Stereotactic radiosurgery (SRS) is commonly performed in patients with trigeminal neuralgia, and numerous investigators have found that facial pain outcomes after this procedure are better for patients in whom prior surgery did not fail. Researchers in some centers claim that the results of SRS are equivalent to posterior fossa exploration (PFE). The goal in this study was to verify that claim. Information was retrieved from a prospectively maintained database of patients less than 70 years old with idiopathic trigeminal neuralgia who underwent PFE (55 patients) or SRS (28 patients) as their initial surgery between 1999 and 2004. Of the two groups, patients who underwent radiosurgery were older (60.5 compared with 50.7 years, p<0.001). Microvascular decompression was performed in 49 patients (89%) and partial nerve section was performed in six (11%) in the PFE group. The mean maximum dose for SRS was 89.1 Gy. At a mean follow-up duration of 25.5 months, patients who had undergone PFE were more commonly pain free without medications (75% at 1 year, 72% at 3 years) compared with the patients treated with SRS (59% at 1 and 3 years; p = 0.01). Additional surgery was performed in 10 patients (18%) after PFE, compared with eight patients (29%) after SRS (p = 0.4). Eight patients (15%) had either new facial numbness (six cases) or dysesthesias (two cases) after PFE, whereas 12 (43%) had either new facial numbness (eight cases) or dysesthesias (four cases) after SRS. No correlation was noted between the development of facial numbness and facial pain outcome after PFE (p = 0.37), whereas patients in whom trigeminal dysfunction developed after radiosurgery were more frequently free of pain (p = 0.02). The results support PFE as a more effective primary surgery than SRS in patients with idiopathic trigeminal neuralgia. Moreover, injury to the trigeminal nerve during PFE is not required to achieve excellent facial pain outcomes.

Percutaneous retrogasserian glycerol rhizotomy for patients with idiopathic trigeminal neuralgia: a prospective analysis of factors related to pain relief

The goal of this study was to analyze prospectively factors associated with facial pain outcomes after percutaneous retrogasserian glycerol rhizotomy (PRGR) for patients with medically unresponsive idiopathic trigeminal neuralgia. Between July 1999 and December 2003, 98 patients underwent PRGR in the manner described by Håkanson. The mean patient age was 72.1 years and the average pain duration prior to PRGR was 8.6 years. Fifty patients (51%) had previously undergone surgery. In six patients (6%), the trigeminal cistern could not be defined and the procedure was aborted; six patients were lost to follow-up review. An excellent facial pain outcome was defined as the absence of facial pain without medications. Thirty-two (35%) of 92 patients either received no benefit (17 patients) or experienced recurrent pain (15 patients) and required additional surgery at a mean of 7.5 months after PRGR; the mean duration of follow-up review in the other 60 patients was 28.7 months (range 3-52 months). Including patients who did not receive a glycerol injection, the 1- and 3-year chances of an excellent facial pain outcome were 61 and 50%, respectively. A multivariate analysis of clinical and surgical factors showed that the facial pain exhibited on glycerol injection correlated with excellent facial pain outcomes (relative risk [RR] = 1.02; 95% confidence interval [CI] 0.26-1.77; p < 0.01), whereas patients who experienced any constant pain less frequently had excellent outcomes (RR = 1.13; 95% CI 0.06-2.20; p = 0.04). Forty-six patients (53%) experienced either mild numbness/parathesias (39 patients) or dysesthesias (seven patients). New trigeminal deficits after PRGR were associated with excellent facial pain outcomes (RR = 1.25; 95% CI 0.56-1.93; p < 0.001). Percutaneous retrogasserian glycerol rhizotomy remains a good operation for patients with medically unresponsive trigeminal neuralgia who are considered poor candidates for posterior fossa exploration. Predictive factors for success include patients without any constant facial pain, patients with immediate facial pain during glycerol injection, and patients with new trigeminal deficits after PRGR.

Repeat radiosurgery for idiopathic trigeminal neuralgia

Although frequently performed, the efficacy and safety of repeat trigeminal neuralgia radiosurgery is not well described. Between August 1997 and December 2002, 19 patients (9 men, 10 women) underwent repeat trigeminal neuralgia radiosurgery. The median interval between procedures was 16 months. The median dose (based on an output factor of 0.87 for the 4-mm collimator) for repeat radiosurgery was 76.1 Gy; the median additive dose was 163.1 Gy. Outcomes were defined as excellent (no pain, no medications), good (no pain, reduced medications), fair (>50% pain reduction), and poor. Median follow-up was 24 months. Outcomes after repeat radiosurgery were excellent (n = 14, 74%), good (n = 1, 5%), fair (n = 3, 16%), and poor (n = 1, 5%). Two patients had recurrent pain at 7 and 22 months; 71% and 61% of patients had an excellent outcome at 1- and 2-years after radiosurgery, respectively. Eleven patients (58%) described facial parathesias (n = 3), numbness (n = 5) or dyesthesias (n = 3). Two patients (11%) developed corneal numbness. Nine of 11 patients (82%) with new trigeminal deficits had excellent outcomes at last follow-up compared with 3 of 8 patients (38%) with unchanged facial sensation (p = 0.07). Repeat trigeminal neuralgia radiosurgery at the dosage described has better facial pain outcomes than primary radiosurgery. However, because the procedure is nonselective and the rate of bothersome numbness was relatively high (16%), dose reduction is recommended to reduce the morbidity of repeat trigeminal neuralgia radiosurgery.

High-dose trigeminal neuralgia radiosurgery associated with increased risk of trigeminal nerve dysfunction.

Stereotactic radiosurgery is being used with more frequency in the management of patients with trigeminal neuralgia. To improve facial pain outcomes, many centers have increased the prescribed radiation dose to the trigeminal nerve. Between April 1997 and December 1999, 68 patients underwent radiosurgery for trigeminal neuralgia with use of the Leksell gamma knife (Elekta Instruments, Norcross, GA) and a single 4-mm isocenter of radiation. Twenty-seven patients (40%) received 70 Gy (low dose) of irradiation and 41 patients (60%) received 90 Gy (high dose). The groups were similar with regard to age, sex, duration of pain, number of prior surgeries, and preexisting trigeminal deficits. The primary facial pain outcomes for analysis were excellent (pain-free, no medications) and good (pain-free, reduced medications). The mean length of follow-up after radiosurgery was 14.4 months (range, 2-36 mo). At last follow-up examination, 11 (41%) of the 27 patients with low-dose radiosurgery remained pain-free compared with 25 (61%) of the 41 patients with high-dose radiosurgery (P = 0.17). Additional surgery was performed in 12 low-dose patients (44%) and 8 high-dose patients (20%) (P = 0.05). High-dose radiosurgery was associated with an increased rate of permanent trigeminal nerve dysfunction (54% versus 15%, P = 0.003). Bothersome dysesthesias occurred in 13 high-dose patients (32%), whereas only 1 low-dose patient had this complication (P = 0.01). Three high-dose patients (8%) developed corneal numbness after radiosurgery. Pain recurred with more frequency in patients not developing trigeminal nerve dysfunction after radiosurgery (9 of 22 patients, 41 %) compared with those who sustained facial numbness, paresthesias, or dysesthesias (4 of 27 patients, 15%); however, the difference was not statistically significant (P = 0.08). Higher doses of radiation may correlate with better facial pain outcomes after radiosurgery for trigeminal neuralgia. However, the incidence of significant trigeminal nerve dysfunction is markedly increased after radiosurgery for patients receiving high-dose radiosurgery. Because of the nonselective nature of this ablative technique, dose prescription should be limited to less than 90 Gy.

Stereotactic radiosurgery for tumor-related trigeminal pain.

Between 1 and 6% of patients who are diagnosed with facial pain syndromes have tumors that involve the trigeminal nerve. We report the effects of stereotactic radiosurgery on tumor-related trigeminal pain. We reviewed results, from a prospective database, for 24 consecutive patients with cranial base tumors and either trigeminal neuralgia (n = 9) or painful trigeminal neuropathy (n = 15) who underwent stereotactic radiosurgery during an 8-year period. The tumor was the radiosurgical target for these patients (not the trigeminal nerve or ganglion). The median clinical follow-up period after radiosurgery was 45 months (range, 12-90 mo); the median neuroimaging follow-up period was 36 months (range, 5-86 mo). There were 20 women and 3 men, with an average age of 57 years (range, 33-79 yr). One patient had bilateral facial pain and underwent staged radiosurgery. Pathological classification indicated 16 meningiomas and 8 malignant cranial base tumors (adenoid cystic carcinoma, n = 6; squamous cell carcinoma, n = 2). Twelve of 24 patients (50%) were initially free of pain, and another 11 patients (46%) reported that they experienced significant improvements in their trigeminal pain syndromes after radiosurgery. The tumor histological type, quality of facial pain, preexisting facial numbness, and marginal and maximal radiation doses were not related to postradiosurgical facial pain outcomes. Three patients with malignant cranial base carcinomas developed recurrent facial pain, 1 to 9 months after radiosurgery, which was related to tumor progression outside the irradiated volume. One patient (4%) developed new partial V2 numbness after radiosurgery. Radiosurgery proved to be effective in improving tumor-related trigeminal pain for the majority of patients with either benign or malignant cranial base tumors. Recurrence of trigeminal pain is frequent for patients with malignant cranial base carcinomas and is related to tumor progression.