Repeat microvascular decompression for patients with persistent or recurrent trigeminal neuralgia: Prognostic factors and long-term outcomes

Treatment of recurrent trigeminal neuralgia after microvascular decompression: How to select

BACKGROUND

This study aimed to investigate individualized treatment strategies and clinical outcomes in patients with recurrent trigeminal neuralgia after undergoing microvascular decompression (MVD).

METHODS

One hundred forty-four patients with recurrent trigeminal neuralgia after MVD were retrospectively examined and grouped according to treatment. Surgical efficacy and pain recurrence were analyzed as outcomes.

RESULTS

Repeat craniotomy was performed in 31 patients (21.5 %), percutaneous balloon compression (PBC) in 67 (46.5 %), and radiofrequency thermocoagulation (RFT) in 46 (32.0 %). Effectiveness did not differ among the three types of treatment (P = 0.052). The incidence of postoperative complications, including trigeminal nerve cardiac reflex, facial numbness, and mastication weakness, was lower in the craniotomy group than the PBC and RFT groups (P < 0.001). The 5-year pain recurrence rate was significantly higher than the 1-year rate in all groups. Although the 1-year pain recurrence rate did not differ among the groups, the 5-year rate was significantly lower in the repeat craniotomy group than the other groups (P < 0.001).

CONCLUSION

Patients with recurrent trigeminal neuralgia after MVD should be treated based on imaging evaluation and general condition. Repeat craniotomy, PBC, and RFT are all effective. Incidence of postoperative complications and long-term pain recurrence-free survival are superior for repeat craniotomy.

Microvascular Decompression Using the Gelatin Sponge Insertion Technique for Trigeminal Neuralgia: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

Microvascular decompression (MVD) is the primary surgical intervention for trigeminal neuralgia (TN), with Teflon being the most conventional decompressing material. However, Teflon has been associated with adhesion and granulomas after MVD, which closely correlated with the recurrence of TN. Therefore, we developed a new technique to prevent direct contact between Teflon and nerve. The purpose of this study is to compare the efficacy of MVD using the gelatin sponge (GS) insertion technique with that of Teflon inserted alone in treating primary TN.

METHODS

We retrospectively analyzed the medical records and the follow-up data of 734 patients with unilateral primary TN who underwent MVD at our center from January 2014 to December 2019. After exclusions, we identified 313 cases of GS-inserted MVD and 347 cases of traditional MVD. The follow-up exceeded 3 years.

RESULTS

The operating time of the GS-inserted group was longer than that of the Teflon group (109.38 ± 14.77 vs 103.53 ± 16.02 minutes, P < .001). There was no difference between 2 groups in immediate surgical outcomes and postoperative complications. The yearly recurrence rate for GS-inserted MVD was lower at first (1.0%), second (1.2%), and third (1.2%) years after surgery, compared with its counterpart of Teflon group (3.7%, 2.9%, and 1.7% respectively). The first-year recurrence rate (P = .031) and total recurrence rate in 3 years (P = .013) was significantly lower in the GS-inserted group than Teflon group. Kaplan-Meier survival analysis demonstrated better outcomes in GS-inserted MVD groups (P = .020).

CONCLUSION

The application of the GS insertion technique in MVD reduced first-year postoperative recurrence of TN, with similar complications rates compared with traditional MVD.

Microvascular decompression for trigeminal neuralgia: a single-center experience with 516 cases, including 32 patients with multiple sclerosis

BACKGROUND AND OBJECTIVES

To evaluate the effectiveness and long-term pain relief of microvascular decompression (MVD) for "typical" trigeminal neuralgia (TN), including patients affected by multiple sclerosis (MS).

METHODS

Between January 2011 and December 2022, 516 consecutive patients presenting with trigeminal neuralgia and a diagnosed neurovascular conflict at MRI underwent microvascular decompression surgery in our neurosurgery department. Ten surgeons with different ages and experiences performed the surgical procedures. Pain improvement, re-operation rate, and complication rates were retrospectively collected and analyzed.

RESULTS

516 patients were included (214 males 302 females, ranging from 12 to 87 years), including 32 patients with multiple sclerosis. Neurovascular compression was found in all cases during surgery. Barrow Neurological Institute pain intensity scale with a score of I was achieved in 404 patients (78,29%), a score II or III was obtained in 100 cases (19,37%) and a score of IV and V in 12 patients (2,32%). In the multiple sclerosis subset of patients, a BNI score of I was achieved in 21/32 (65.62%). The pain recurrence rate of our series was 15.11%. The follow-up for all patients was at least of 13 months, with a mean follow-up of 41.93 months (± 17.75 months, range 13-91 months). Neither intraoperative mortality nor major intra-operative complications occurred in the analyzed series. The re-operation rate was 12.98%. Thermorhizotomy, percutaneous balloon compression, cyber-knife radiosurgery, or new MVD were the surgical techniques utilized for re-operations.

CONCLUSIONS

MVD may be considered an effective and safe surgical technique for TN, and in patients affected by multiple sclerosis, it may be proposed even if a less favorable outcome has to be expected with respect to classic TN patients. Larger studies focusing on the relation of multiple sclerosis with neurovascular compression are required.

Microsurgical posterior fossa re-exploration for recurrent trigeminal neuralgia after previous microvascular decompression: common grounds-scarring, deformation, and the "piston effect"

OBJECTIVE

Microvascular decompression (MVD) is a well-accepted treatment modality for trigeminal neuralgia (TN) with high initial success rates. The causes for recurrence of TN after previously successful MVD have not been fully clarified, and its treatment is still a matter of debate. Here, we present the surgical findings and the clinical outcome of patients with recurrent TN after MVD who underwent posterior fossa re-exploration.

METHODS

Microsurgical posterior fossa re-exploration was performed in 26 patients with recurrent TN (mean age 59.1 years) who underwent MVD over a period of 10 years. The trigeminal nerve was exposed, and possible factors for recurrent TN were identified. Arachnoid scars and Teflon granulomas were dissected meticulously without manipulating the trigeminal nerve. Outcome of posterior fossa re-exploration was graded according to the Barrow Neurological Institute (BNI) pain intensity score. Follow-up was analyzed postoperatively at 3, 12, and 24 months and at the latest available time point for long-term outcome.

RESULTS

The mean duration of recurrent TN after the first MVD was 20 months. Pain relief was achieved in all patients with recurrent TN on the first postoperative day. Intraoperative findings were as follows: arachnoid scar tissue in 22/26 (84.6%) patients, arterial compression in 1/26 (3.8%), venous contact in 8/26 (30.8%), Teflon granuloma in 14/26 (53.8%), compression by an electrode in Meckel's cave used for treatment of neuropathic pain in 1/26 (3.8%), evidence of pulsations transmitted to the trigeminal nerve through the Teflon inserted previously/scar tissue ("piston effect") in 15/26 (57.7%), and combination of findings in 18/26 (69.2%). At long-term follow-up (mean 79.5 months; range, 29-184 months), 21/26 (80.8%) patients had favorable outcome (BNI I-IIIa). New hypaesthesia secondary to microsurgical posterior fossa re-exploration occurred in 5/26 (19.2%) patients.

CONCLUSIONS

Posterior fossa re-exploration avoiding manipulation to the trigeminal nerve, such as pinching or combing, may be a useful treatment option for recurrent TN after previously successful MVD providing pain relief in the majority of patients with a low rate of new hypaesthesia.

Imaging the neural substrate of trigeminal neuralgia pain using deep learning

Trigeminal neuralgia (TN) is a severe and disabling facial pain condition and is characterized by intermittent, severe, electric shock-like pain in one (or more) trigeminal subdivisions. This pain can be triggered by an innocuous stimulus or can be spontaneous. Presently available therapies for TN include both surgical and pharmacological management; however, the lack of a known etiology for TN contributes to the unpredictable response to treatment and the variability in long-term clinical outcomes. Given this, a range of peripheral and central mechanisms underlying TN pain remain to be understood. We acquired functional magnetic resonance imaging (fMRI) data from TN patients who (1) rested comfortably in the scanner during a resting state session and (2) rated their pain levels in real time using a calibrated tracking ball-controlled scale in a pain tracking session. Following data acquisition, the data was analyzed using the conventional correlation analysis and two artificial intelligence (AI)-inspired deep learning methods: convolutional neural network (CNN) and graph convolutional neural network (GCNN). Each of the three methods yielded a set of brain regions related to the generation and perception of pain in TN. There were 6 regions that were identified by all three methods, including the superior temporal cortex, the insula, the fusiform, the precentral gyrus, the superior frontal gyrus, and the supramarginal gyrus. Additionally, 17 regions, including dorsal anterior cingulate cortex (dACC) and the thalamus, were identified by at least two of the three methods. Collectively, these 23 regions are taken to represent signature centers of TN pain and provide target areas for future studies seeking to understand the central mechanisms of TN.

Microvascular decompression: Diversified of imaging uses, advantages of treating trigeminal neuralgia and improvement after the application of endoscopic technology

Classical trigeminal neuralgia (CTN) is a unilateral and severe facial pain disease, which seriously affects the patient's quality of life. Microvascular decompression (MVD) is currently the most effective surgical method, and it is the only treatment for the etiology of CTN. Imaging for MVD has been increasingly used, and the advantages and disadvantages of endoscopy-assisted vascular decompression surgery have been controversially debated. In this review, we aimed to discuss the advantages of MVD in the treatment of patients with CTN, the importance of using imaging in disease management, and the improvements of vascular decompression surgery through the application and maturity of endoscopic techniques. Compared with other surgical methods, MVD has more prominent short- and long-term treatment effects. Its selection depends on the accurate discovery of neurovascular compression by preoperative imaging. Moreover, magnetic resonance imaging plays a diverse role in MVD, not only in identifying the responsible vessels but also in determining the prognosis and as a tool for scientific research. The use of endoscopic techniques provides improved visualization of the MVD and additional benefits for vascular decompression surgery.

Narrow ovale foramina may be involved in the development of primary trigeminal neuralgia

Background

The etiology of primary trigeminal neuralgia remains unclear and is worthy of further study; In this study, the morphometric characteristics of ovale foramina between various groups were compared and analyzed to explore the novel cause of primary trigeminal neuralgia.

Methods

High-resolution three-dimensional reconstruction images from head computed tomography of 109 patients with primary trigeminal neuralgia affecting the third branch of the trigeminal nerve and 46 healthy controls were retrospectively reviewed. Among the 109 primary trigeminal neuralgia patients, 79 patients with apparent neurovascular compression (not simply contact) demonstrated on MRI or during surgery were divided into the classical trigeminal neuralgia group and 30 patients with MRI showing no significant abnormalities were divided into idiopathic trigeminal neuralgia group. The morphometric parameters including the area, width and length of ovale foramina were examined through the use of radiologic methods.

Results

In this study, the average minimum area, width and length of 79 ovale foramina on the affected and unaffected sides in the classical trigeminal neuralgia group were 21.83 ± 8.45, 21.94 ± 7.93 mm², 2.32 ± 0.91, 2.58 ± 0.81, 5.32 ± 1.29, and 5.26 ± 1.21 mm, respectively. No significant difference in these parameters was observed (p > 0.05). However, in the idiopathic trigeminal neuralgia group, the average minimum area, width and length of 30 ovale foramina were 21.33 ± 8.21, 22.85 ± 8.36 mm², 2.25 ± 0.90, 2.79 ± 0.96, 5.20 ± 1.27, and 5.28 ± 1.19 mm, respectively. The width on the symptomatic side was significantly smaller (p = 0.03) than that on the asymptomatic side. No significant difference in area (p = 0.48) or length (p = 0.79) was observed. In addition, when compared with the healthy control group, the area and width of ovale foramina on the symptomatic side in both groups were significantly smaller. No significant difference in length was observed.

Conclusions

By comparing and analyzing the statistical data, it can be inferred that a narrow foramen ovale is associated with primary trigeminal neuralgia, as well as its recurrence after microvascular decompression.

Recurrent Trigeminal Neuralgia: A Case Series and a Review of the Literature

Trigeminal neuralgia is a peripheral neuropathy characterized by intermittent episodes of severe facial pain originating in the sensory nucleus of the trigeminal nerve. The most commonly involved area is the mandibular division with a higher prevalence on the right side. Advances in the field of MRI have played an important role in its diagnosis, especially in presurgical assessment, to probe into any secondary causes of nerve compression and/or neurovascular conflict. The condition is primarily managed medically, although many patients may require surgical or radiotherapeutic intervention. A recurrence rate ranging from 6 to 41% has been postulated. Reasons for recurrence are mainly attributed to improper operative techniques, dislocation of the Teflon implant, or granuloma formation. MRI serves as a powerful tool in the segmental evaluation of the trigeminal nerve. A proper diagnosis with a structured treatment protocol is critical for managing such cases of trigeminal neuralgia. In this report, we present a series of two cases of recurrent trigeminal neuralgia.

Treatment of redo-microvascular decompression or internal neurolysis plus microvascular decompression for recurrent trigeminal neuralgia: a review of long-term effectiveness and safety

Objective

We examined the clinical characteristics and outcomes of patients with recurrent trigeminal neuralgia (TN) and assessed the long-term efficacy and safety of microvascular decompression (MVD) to treat typical recurrent TN.

Methods

We identified 3024 patients who underwent MVD for treatment of TN at the China-Japan Friendship Hospital from March 2009 to December 2020. We retrospectively analyzed the data and outcomes of 137 patients who underwent redo-MVD and 74 patients who did not undergo redo-MVD as the control group. These outcomes were evaluated using the Barrow Neurological Institute scoring system.

Results

Recurrence in 68 of the 137 patients was due to incomplete or absent decompression or new responsible vessels. To ensure thorough pain relief, redo-MVD should include decompression of both the trigeminal root entry zone and the peripheral nerve segments, where blood vessels can cause symptoms. Factors associated with reduced effectiveness of redo-MVD were no period of initial pain relief after the first MVD and a longer duration of symptoms before the first MVD.

Conclusions

Redo-MVD should not be excluded as a treatment option for patients with refractory TN who develop recurrent pain after a first MVD procedure.

Teflon Granuloma: A Common Cause of Recurrent Trigeminal Neuralgia

BACKGROUND

Trigeminal neuralgia (TN) is a common pain syndrome of the nervous system,. Although about 90% patients who were refractory to medications could be free from pain after microvascular decompression (MVD), some patients did experience recurrence. The study aimed to analyze clinical characteristics of patients with recurrent TN, recurrence factors of TN, and prognosis after re-do MVD.

METHODS

Clinical data and at least 12 months follow-up of patients with recurrent TN who underwent re-do MVD in our hospital from 2005 to 2020 were collected and analyzed.

RESULTS

A total of 14 patients with recurrent TN were enrolled eventually; adhesive arachnoid membranes were found in all patients. Teflon granuloma was found in 10 patients, new neurovascular compression (NVC) in 3 patients, and vascular displacement in 1 patient. Pain disappeared in 12 patients and relieved in 2 patients, but 4 patients experienced mild facial numbness and 1 patient suffered from incision infection after re-do MVC. No serious surgery-related complications and pain recurrences were recorded.

CONCLUSIONS

Teflon granuloma was the most common cause of TN recurrence in current study, new NVC was also saw in some patients. Patients with recurrent TN could get satisfactory results from re-do MVD.

A Systematic Review of Repeat Microvascular Decompression for Recurrent or Persistent Trigeminal Neuralgia

OBJECTIVE

When conservative therapy fails, microvascular decompression (MVD) has been the preferred treatment of primary trigeminal neuralgia (TN). However, the management of recurrent or persistent TN after MVD can often be difficult. The purpose of the present systematic review was to objectively analyze and summarize the reported literature regarding the feasibility of repeat MVD.

METHODS

We conducted a database search using the MEDLINE and PubMed databases until July 2020. The search terms used for title and abstract screening were as follows: "recurrent trigeminal neuralgia," "persistent trigeminal neuralgia," "repeat microvascular decompression," and "reexploration." The inclusion criteria for the systematic review were as follows: clinical studies (excluding case studies), repeat MVD treatment of TN, and studies that had recorded the pain relief outcomes, operative findings, and complications (if any).

RESULTS

Of the 1771 initial results obtained, we performed a full text screening of 43 studies, and, ultimately, 19 were deemed eligible. A total of 2247 patients had undergone MVD for TN, of whom, 311 had experienced recurrence (13.84%). Of the 311 patients, 178 had undergone repeat MVD. The average pain-free interval was 27.75 months after the first MVD. The effective rate of repeat MVD was 91.66%, and 71.48% of the patients had had obvious compression found at repeat MVD. The postoperative complication rate after repeat MVD was 37.31% and was due to postoperative adhesions around the nerve and nerve injury caused by partial sensory rhizotomy. The most common complication after repeat MVD was facial numbness (21.89%), although the incidence of other complications was <5%.

CONCLUSIONS

For patients with recurrent or persistent pain after MVD, the findings from our systematic review support that repeat MVD remains a feasible treatment for recurrent or persistent TN.

Long Time Efficacy and Safety of Microvascular Decompression Combined with Internal Neurolysis for Recurrent Trigeminal Neuralgia

Objective

To explore the clinical efficacy and safety of microvascular decompression (MVD) combined with internal neurolysis (IN) in the treatment of recurrent trigeminal neuralgia (TN) after MVD.

Methods

Sixty-four patients with recurrent TN admitted to the hospital from January 2014 to December 2017 were divided into two groups according to the surgical method. Twenty-nine patients, admitted from January 2014 to December 2015, were treated with MVD alone, whereas 35 admitted from January 2016 to December 2017 were treated with MVD+IN. The postoperative efficacy, complications, and pain recurrence rate of the two groups were analyzed.

Results

The efficacy of the MVD+IN and MVD groups were 88.6% and 86.2%, and the cure rates were 77.1% and 65.5% respectively. There was no statistically significant difference between the two groups (p>0.05). The cure rate (83.3%) of patients in the MVD+IN group, who were only found thickened arachnoid adhesions during the operation that could not be fully released, was significantly higher than that of the MVD group (30.0%) (p<0.05), while the efficacy (91.7% vs. 70%) of the two groups was not statistically different (p>0.05). For patients whose arachnoid adhesions were completely released, there had no significant difference (p>0.05) in the efficacy (87% vs. 94.7%) and recurrence rate (5.0% vs. 11.1%). The incidence of postoperative facial numbness (88.6%) in the MVD+IN group was higher than that in the MVD group (10.3%) (p<0.01). The long-term incidence of facial numbness was not statistically significant (p>0.05). In the 18–36 months follow-up, the recurrence rate of patients in the MVD+IN group (9.7%) and in the MVD group (16%) were not statistically different (p>0.05).

Conclusion

A retrospective comparison of patients with recurrent TN showed that both MVD and MVD combined with IN can effectively treat recurrent TN. Compared with MVD alone, MVD combined with IN can effectively improve the pain cure rate of patients with recurrent TN who have only severe arachnoid adhesions. The combination does not increase the incidence of long-term facial numbness and other complications.

Redo surgery for trigeminal neuralgia: reasons for re-exploration and long-term outcomes

BACKGROUND

To investigate the causes of failure and recurrence after microvascular decompression (MVD) for trigeminal neuralgia (TGN) and to analyze the results of redo surgery.

METHODS

Sixty-three cases of redo surgery were retrospectively reviewed. Reasons for re-exploration were categorized into 4 groups based on the operative findings. Patient characteristics, outcomes of re-exploration, and operative complications were analyzed by Kaplan-Meier and logistic regression analyses.

RESULTS

Reasons for redo surgery were divided into arterial compression in 13 patients (21%), venous compression in 11 patients (17%), prosthesis-related in 25 patients (40%), and adhesion or negative exploration in 14 patients (22%). Immediate pain relief was obtained in 59 patients (94%) postoperatively with newly developed facial numbness in 17 patients (27%). Of these, 48 patients (76%) maintained pain-free 1 year postoperatively. Overall recurrence was noted in 17 patients (27%) during the median 49-month follow-up period. Most recurrences occurred within 1 year after redo surgery, but the prosthesis-related patients showed a continuous recurrence up to 4 years. Patients having vascular compression showed significantly better pain control than those without vascular contact in Kaplan-Meier analyses (p = 0.0421). No prognostic factor for pain-free 1 year after redo surgery was found.

CONCLUSIONS

Redo surgery is effective for patients with remaining vascular compression rather than those without vascular contact. Teflon contact onto the nerve root should be avoided because it is a potential risk for recurrence and causes poor prognosis after redo surgery.

Microvascular Decompression versus Stereotactic Radiosurgery for Trigeminal Neuralgia: A Single-Institution Experience

OBJECTIVE

Microvascular decompression (MVD) is the standard surgical procedure for patients with medically refractory trigeminal neuralgia (TN). Stereotactic radiosurgery (SRS) has gained increasing popularity as a less invasive technique. We report our institution's outcome in the surgical treatment of TN (MVD vs. SRS), taking patient's age and gender into consideration.

METHODS

We retrospectively reviewed a prospectively collected database of patients undergoing MVD or SRS for type 1 idiopathic TN between 2004 and 2019 at the University of Iowa. Standardized data collection focused on preoperative clinical characteristics and postoperative outcomes including the Barrow Neurological Institute (BNI) Pain Intensity Score.

RESULTS

A total of 111 patients underwent MVD and 103 patients underwent SRS for TN. Patients were younger in the MVD (median, 60 years) than SRS (median, 72 years) group. More females (58%) than males (42%) had TN. Multivariate ordinal regression analysis showed that an outcome of BNI score I-II (P = 0.365) and III (P = 0.736) can be achieved with either MVD or SRS; however, BNI score IV (P = 0.031) and V (P = 0.022) were more associated with SRS. Six percent of patients in the MVD group and 26% in the SRS group developed pain recurrence and required a second operation. Nine of 10 patients who underwent MVD after failed SRS had complete pain relief.

CONCLUSIONS

Factoring in patients' age and gender, both MVD and SRS can achieve a favorable outcome for medically refractory TN, although BNI scores of IV and V were more common with SRS.

Multiple Recurrences of Trigeminal Neuralgia Caused by Deformation of the Trigeminal Nerve

Microvascular decompression (MVD) is frequently used for the treatment of trigeminal neuralgia (TN). We present a case of TN with multiple recurrences despite different interventions. A 50-year-old patient presented with a five-year history of left TN. He initially had an MVD with Teflon padding that eliminated his pain for a year. When pain recurred, he went on to stereotactic radiosurgery, which did not help. He then had two percutaneous retrogasserian glycerol injections, the first one relieved pain for a year and the second only six months. After the second recurrence, we repeated the magnetic resonance imaging (MRI) of the brain, and it showed kinking of the nerve with the padding in place. We decided to re-explore the nerve based on the MRI findings. Intraoperatively, we observed the Teflon padding had become adherent to the petrous bone which caused deformation of the nerve. We did adhesiolysis with debulking of the padding, following which the nerve appeared more relaxed. Postoperatively, the patient had immediate resolution of his pain. At eight-month follow-up, the patient remained pain-free. Multiple factors can be involved in recurrence of TN after MVD. In this case, the size of the padding, continued distortion from the offending artery in addition to scarring from radiosurgery may have contributed to the deformation of the nerve and the recurrence of symptoms. A new MRI can be beneficial when the neuralgia symptoms recur in delayed fashion after successful MVD. Also, the use of a more compact padding material, like Gore-Tex, may cause less deformation of the nerve.