Does a small posterior fossa increase nerve vascular conflict in trigeminal neuralgia?

✓ Thirty-five patients with trigeminal neuralgia (TN) bilaterally underwent posterior fossa microvascular decompression (MVD) between 1971 and 1984. They comprised 5.0% of a larger series of 699 patients with TN who underwent MVD during that interval. Compared to the subgroup of 664 patients with only unilateral symptoms, the population with bilateral TN included a greater percentage of females (74% vs. 58%, p < 0.1), a higher rate of “familial” TN (17% vs. 4.1%, p < 0.001), and an increased incidence of additional cranial nerve dysfunction (17% vs. 6.6%, p < 0.05) and hypertension (34% vs. 19%, p < 0.05). Of the 35 patients with bilateral TN, 10 underwent bilateral MVD (22 procedures) and 25 underwent unilateral MVD (30 procedures). In the latter patients, pain on the nonoperative side was well controlled with medication alone or had previously been treated by ablative procedures. Good or excellent pain control was achieved after one MVD was performed in 40 of the 45 sides treated (89%), and was maintained 1, 5, and 10 years after surgery in 82%, 66%, and 60%, respectively, based on life-table analysis. Six of 10 patients with recurrent symptoms underwent repeat unilateral MVD. Good or excellent long-term pain control was maintained in all six. With these repeat procedures included, symptom control at 1, 5, and 10 years after initial surgery was maintained in 87%, 78%, and 78% of the treated sides, respectively. Overall, 26 of 35 patients (74%) maintained good or excellent pain relief throughout the duration of the study (mean follow-up period 75 months) without resumption of regular medication usage. Although preoperative neurological deficits resulting from previous ablative procedures were seen in the majority of patients before MVD, no patient developed new major trigeminal sensory loss or masseter weakness after MVD. Operative mortality was zero. The results indicate that posterior fossa MVD is an effective and relatively safe treatment for the majority of patients with bilateral “idiopathic” TN, avoiding the risks of bilateral trigeminal nerve injury seen with other approaches.

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Long-term outcome after operation for trigeminal neuralgia in patients with posterior fossa tumors

Journal of Neurosurgery ◽

10.3171/jns.1996.84.5.0818 ◽

1996 ◽

Vol 84 (5) ◽

pp. 818-825 ◽

Cited By ~ 63

Author(s):

Fred G. Barker ◽

Peter J. Jannetta ◽

Ramesh P. Babu ◽

Spiros Pomonis ◽

David J. Bissonette ◽

...

Keyword(s):

Trigeminal Neuralgia ◽

Posterior Fossa ◽

Trigeminal Nerve ◽

Posterior Fossa Tumors ◽

Duration Of Symptoms ◽

Long Term Outcome ◽

Entry Zone ◽

Content Type ◽

Root Entry Zone ◽

Fine Print

✓ During a 20-year period, 26 patients with typical symptoms of trigeminal neuralgia were found to have posterior fossa tumors at operation. These cases included 14 meningiomas, eight acoustic neurinomas, two epidermoid tumors, one angiolipoma, and one ependymoma. The median patient age was 60 years and 69% of the patients were women. Sixty-five percent of the symptoms were left sided. The median preoperative duration of symptoms was 5 years. The distribution of pain among the three divisions of the trigeminal nerve was similar to that found in patients with trigeminal neuralgia who did not have tumors; however, more divisions tended to be involved in the tumor patients. The mean postoperative follow-up period was 9 years. At operation, the root entry zone of the trigeminal nerve was examined for vascular cross-compression in 21 patients. Vessels compressing the nerve at the root entry zone were observed in all patients examined. Postoperative pain relief was frequent and long lasting. Using Kaplan—Meier methods the authors estimated excellent relief in 81% of the patients 10 years postoperatively, with partial relief in an additional 4%.

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Foramen magnum decompression without bone removal: C1–C2 posterior fixation for Chiari with congenital atlantoaxial dislocation/basilar invagination

Surgical Neurology International ◽

10.25259/sni-38-2019 ◽

2019 ◽

Vol 10 ◽

pp. 38 ◽

Cited By ~ 5

Author(s):

Pravin Salunke ◽

Madhivanan Karthigeyan ◽

Puneet Malik

Keyword(s):

Posterior Fossa ◽

Craniovertebral Junction ◽

Basilar Invagination ◽

Foramen Magnum ◽

Atlantoaxial Dislocation ◽

Posterior Fixation ◽

Foramen Magnum Decompression ◽

Radiological Data ◽

C2 Fixation ◽

Small Posterior Fossa

Background: Atlantoaxial dislocation (AAD) and basilar invagination (BI) may coexist with Chiari malformations (CM) and a small posterior fossa volume. These are typically treated with craniovertebral junction fusion and foramen magnum decompression (FMD). Here, we evaluated whether C1–C2 posterior reduction and fixation (which possibly opens up the ventral foramen magnum) would effectively treat AAD and CM without additionally performing FMD. Methods: This is a retrospective analysis of 38 patients with BI, AAD, and CM who underwent C1–C2 posterior reduction and fusion without FMD. Baseline and follow-up clinical, demographic, and radiological data were evaluated. Results: The vast majority of patients (91.9%) improved both clinically and radiographically following C1–C2 fixation alone; none later required direct FMD. Notably, AAD was irreducible in 25 (65.8%) patients. Preoperatively, syringomyelia was present in 28 (73.7%) patients and showed resolution. In 3 (8.1%) patients, resolution of syrinxes did not translate into clinical improvement. Of interest, 5 patients who sustained inadvertent dural lacerations exhibited transient postoperative neurological worsening. Conclusions: Posterior C1–C2 distraction and fusion alone effectively treated AAD, BI, accompanied by CM. The procedure sufficiently distracted the dens, reversed dural tenting, and restored the posterior fossa volume while relieving ventral brainstem compression making FMD unnecessary. Surgeons should, however, be aware that inadvertent dural lacerations might contribute to unwanted neurological deterioration.

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Microvascular decompression for typical trigeminal neuralgia: Personal experience with intraoperative neuromonitoring with level-specific-CE-Chirp® brainstem auditory evoked potentials in preventing possible hearing loss

Surgical Neurology International ◽

10.25259/sni_702_2020 ◽

2020 ◽

Vol 11 ◽

pp. 388

Author(s):

Luciano Mastronardi ◽

Franco Caputi ◽

Guglielmo Cacciotti ◽

Carlo Giacobbo Scavo ◽

Raffaelino Roperto ◽

...

Keyword(s):

Hearing Loss ◽

Trigeminal Neuralgia ◽

Evoked Potentials ◽

Posterior Fossa ◽

Microvascular Decompression ◽

Auditory Evoked Potentials ◽

Intraoperative Neuromonitoring ◽

Brainstem Auditory Evoked Potentials ◽

Group A ◽

Group B

Background: Permanent hearing loss after posterior fossa microvascular decompression (MVD) for typical trigeminal neuralgia (TTN) is one of the possible complications of this procedure. Intraoperative brainstem auditory evoked potentials (BAEPs) are used for monitoring the function of cochlear nerve during cerebellopontine angle (CPA) microsurgery. Level-specific (LS)-CE-Chirp® BAEPs are the most recent evolution of classical click BAEP, performed both in clinical studies and during intraoperative neuromonitoring (IONM) of acoustic pathways during several neurosurgical procedures. Methods: Since February 2016, we routinely use LS-CE-Chirp® BAEPs for monitoring the function of cochlear nerve during CPA surgery, including MVD for trigeminal neuralgia. From September 2011 to December 2018, 71 MVDs for TTN were performed in our department, 47 without IONM of acoustic pathways (Group A), and, from February 2016, 24 with LS-CE-Chirp BAEP (Group B). Results: Two patients of Group A developed a permanent ipsilateral anacusia after MVD. In Group B, we did not observe any permanent acoustic deficit after surgery. In one case of Group B, during arachnoid dissection, intraoperative LS-CE-Chirp BAEP showed a temporary lag of V wave, resolved in 5 min after application of intracisternal diluted papaverine (0.3% solution without excipients). Conclusion: MVD is widely considered a definitive surgical procedure in the management of TTN. Even though posterior fossa MVD is a safe procedure, serious complications might occur. In particular, the use of IONM of acoustic pathways during MVD for TTN might contribute to prevention of postoperative hearing loss.

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Improvement of Hydrocephalus in Patients with Chiari Malformation After Posterior Fossa Decompression

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA ◽

10.22290/jbnc.v27i1.801 ◽

2018 ◽

Vol 27 (1) ◽

pp. 71-73

Author(s):

Lindolfo Carlos Heringer ◽

Matheus Fernandes De Oliveira ◽

Ulysses Oliveira De Sousa ◽

Wanderley Cerqueira De Lima ◽

Ricardo Vieira Botelho

Keyword(s):

Posterior Fossa ◽

Chiari Malformation ◽

Clinical Symptoms ◽

Foramen Magnum ◽

Posterior Fossa Decompression ◽

Type I ◽

Chiari Malformation Type I ◽

Cisterna Magna ◽

Long Time ◽

Small Posterior Fossa

Introduction. The association between hydrocephalus and Chiari malformation (CM) has not been described frequently. Ventricular dilation affects 7% to 10% of patients with CM, but the ideal choice of surgical treatment is controversial. Wereport a case of a patient with Chiari malformation and hydrocephalus with improvement in clinical symptoms and ventricular dilatation. Case Description. A 19-year-old male complaining of frontal headache when coughing, laughing and during valsalva maneuvers, associated with dizziness for 2 months. Magnetic resonance (MR) showed hydrocephalus and small posterior fossa with overcrowding of contents, characterizing Chiari malformation type I, with cerebellar tonsils protruding through magnum foramen. Patient underwent surgery with posterior fossa decompression in a semi-sitting position and removal of the arc C1.After 3 months of follow-up, headache disappeared becoming asymptomatic. Control MR showed improvement of hydrocephalus with restoration of the cisterna magna and CSF flow. Discussion. Hydrocephalus has been related to CM for a long time. In our case, we performed treatment with intradural and intra-arachnoidal approach with bilateral tonsillectomy without placing ventricular shunt. The cisterna magna was “recreated”. There was improvement of hydrocephalus with decreased Evans ratio index and symptoms disappearance. Although there is no other studies addressing such matter, in this case, the improvement suggests that the CSF compression at the foramen magnum was the cause of associated hydrocephalus with Chiari malformation.

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Small Posterior Fossa as a Predisposition of Neurovascular Conflict

Skull Base ◽

10.1055/s-2005-916553 ◽

2005 ◽

Vol 15 (S 2) ◽

Author(s):

Vasek Masopust ◽

D. Netuka ◽

V. Benes

Keyword(s):

Posterior Fossa ◽

Neurovascular Conflict ◽

Small Posterior Fossa

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Results of Repeat Posterior Fossa Exploration for Patients with Medically Intractable Trigeminal Neuralgia 851

Neurosurgery ◽

10.1227/01.neu.0000309901.82681.66 ◽

2006 ◽

Keyword(s):

Trigeminal Neuralgia ◽

Posterior Fossa

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Patient Reports of Satisfaction after Microvascular Decompression and Partial Sensory Rhizotomy for Trigeminal Neuralgia

Neurosurgery ◽

10.1227/01.neu.0000159883.35957.e0 ◽

2005 ◽

Vol 56 (6) ◽

pp. 1304-1312 ◽

Cited By ~ 109

Author(s):

Joanna M. Zakrzewska ◽

Benjamin C. Lopez ◽

Sung Eun Kim ◽

Hugh B. Coakham

Keyword(s):

Patient Satisfaction ◽

Side Effects ◽

Trigeminal Neuralgia ◽

Posterior Fossa ◽

Microvascular Decompression ◽

Primary Group ◽

Posterior Fossa Surgery ◽

Ablative Surgery ◽

Significant Difference ◽

Primary Procedure

Abstract OBJECTIVE: There are no reports of patient satisfaction surveys after either a microvascular decompression (MVD) or a partial sensory rhizotomy (PSR) for trigeminal neuralgia. This study compares patient satisfaction after these two types of posterior fossa surgery for trigeminal neuralgia, because it is postulated that recurrences, complications, and previous surgical experience reduce satisfaction. METHODS: All patients who had undergone their first posterior fossa surgery at one center were sent a self-complete questionnaire by an independent physician. Among the 44 questions on four standardized questionnaires were 5 questions that related to patient satisfaction and experience of obtaining care. Patients were divided into those having their first surgical procedure (primary) and those who had had previous ablative surgery (nonprimary). RESULTS: Response rates were 90% (220 of 245) of MVD and 88% (53 of 60) of PSR patients. Groups were comparable with respect to age, sex, duration of symptoms, mean duration of follow-up, and recurrence rates. Overall satisfaction with their current situation was 89% in MVD and 72% in PSR patients. Unsatisfied with the outcome were 4% of MVD and 20% of PSR patients, and this is a significant difference (P < 0.01). Satisfaction with outcome was higher in those undergoing this as a primary procedure. In the primary group, satisfaction was dependent on recurrence and complication/side effects status (each P < 0.01), but this was not the case in the nonprimary group. Patients expressed a desire for earlier posterior fossa surgery in 73% of MVD and 58% of PSR patients, and this was highest in the primary group. The final outcome was considered to be better than expected in 80% of MVD and 54% of PSR patients, but 22% of the PSR group (P < 0.01) thought they were worse off. CONCLUSION: Patients undergoing posterior fossa surgery as a primary procedure are most satisfied and PSR patients are least satisfied, partly because of a higher rate of side effects.

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