✓ The authors describe a case of nontraumatic atlantoaxial dislocation secondary to acute rheumatic fever, in which there appeared to be fibrous fusion between the axis and the atlas in the subluxed position. The dislocation was reduced by means of combined traction and steroid therapy. Fibrous fusion occurred in the realigned position after immobilization.
John T. Lucas, Gordon D. Hungerford and Phanor L. Perot Jr.
John T. Lucas, Thomas B. Ducker and Phanor L. Perot Jr.
✓ The authors report the results of a questionnaire regarding the use of hypertonic saline for the control of pain. Of 2105 patients so treated, nearly 11% had an adverse temporary symptom or sign, reported as an untoward reaction; slightly over 1% suffered a significant morbidity, of which paraplegia or quadriplegia was by far the most common, and two patients died (0.1%).
Ann Liu, Elizabeth N. Kuhn, John T. Lucas Jr., Adrian W. Laxton, Stephen B. Tatter and Michael D. Chan
Neurofibromatosis Type 2 (NF2) is a rare autosomal dominant disorder predisposing patients to meningiomatosis. The role of stereotactic radiosurgery (SRS) is poorly defined in NF2, and although the procedure has excellent control rates in the non-NF2 population, its utility has been questioned because radiation has been hypothesized to predispose patients to malignant transformation of benign tumors. To the authors' knowledge, this is the first study to examine the use of SRS specifically for meningiomas in patients with NF2.
The authors searched a tumor registry for all patients with NF2 who had undergone Gamma Knife radiosurgery (GKRS) for meningioma in the period from January 1, 1999, to September 19, 2013, at a single tertiary care cancer center. Medical records were retrospectively reviewed for patient and tumor characteristics and outcomes.
Among the 12 patients who met the search criteria, 125 meningiomas were identified, 87 (70%) of which were symptomatic or progressive and thus treated with GKRS. The median age at the first GKRS was 31 years (interquartile range [IQR] 27–37 years). Five patients (42%) had multiple treatments with a median of 27 months (IQR 14–50 months) until the subsequent GKRS. The median follow-up in surviving patients was 43 months (IQR 34–110 months). The 5-year local tumor control and distant treatment failure rates were 92% and 77%, respectively. Toxicities occurred in 25% of the GKRS treatments, although the majority were Grade 1 or 2. At the last follow-up, 4 patients (33%) had died a neurological death at a median age of 39 years (IQR 37–46 years), and their cases accounted for 45% of all tumors, 55% of all treated tumors, and 58% of all GKRSs. Univariate analysis revealed several predictive variables for distant failure, including male sex (HR 0.28, 95% CI 0.086–0.92, p = 0.036), age at distant failure (HR 0.92, 95% CI 0.90–0.95, p < 0.0001), and prior number of GKRS treatments (HR 1.2, 95% CI 1.1–1.4, p = 0.0049). Local failure, maximum size of the treated tumor, delivered tumor margin dose, and WHO grade were not significant. On multivariate analysis, age at distant failure (HR 0.91, 95% CI 0.88–0.95, p < 0.0001) and prior number of GKRSs (HR 1.3, 95% CI 1.1–1.5, p = 0.004) remained significant. No malignant transformation events among treated tumors were observed.
Radiosurgery represents a feasible modality with minimal toxicity for NF2-associated meningiomas. Increasing patient age was associated with a decreased rate of distant failure, whereas an increasing number of prior GKRS treatments predicted distant failure. Further studies are necessary to determine the long-term patterns of treatment failure in these patients.
Corbin A. Helis, Ryan T. Hughes, Michael T. Munley, J. Daniel Bourland, Travis Jacobson, John T. Lucas Jr., Christina K. Cramer, Stephen B. Tatter, Adrian W. Laxton and Michael D. Chan
Gamma Knife radiosurgery (GKRS) is a commonly used procedure for medically refractory trigeminal neuralgia (TN), with repeat GKRS routinely done in cases of pain relapse. The results of a third GKRS in cases of further pain relapse have not been well described. In this study, the authors report the largest series of patients treated with a third GKRS for TN to date.
Retrospective review of institutional electronic medical records and a GKRS database was performed to identify patients who had been treated with a third GKRS at the authors’ institution in the period from 2010 to 2018. Telephone interviews were used to collect long-term follow-up data. Pain outcomes were measured using the Barrow Neurological Institute (BNI) pain intensity scale, with a score ≤ IIIb indicating successful treatment.
Twenty-two nerves in 21 patients had sufficient follow-up to determine BNI pain score outcomes. Eighteen of 22 cases had a successful third GKRS, with a median durability of pain relief of 3.88 years. There was no significant difference in the durability of pain relief after a third GKRS compared with those of institutional historical controls of prior series of first and second GKRS procedures. Ten cases had new or worsening facial numbness, with 1 case being bothersome. Four cases of toxicity other than facial numbness were reported, including 1 case of corneal abrasions and possible neurotrophic keratopathy. No cases of anesthesia dolorosa were reported. No factors predicting treatment success or the durability of pain relief were identified. Nonnumbness toxicity was more common in those with a proximally placed shot at the third GKRS.
A third GKRS is an effective treatment option for TN patients who have pain relapse after repeat GKRS. Pain outcomes of a third GKRS are similar to those following a first or second GKRS. Toxicity is tolerable in patients with a distally placed shot at the third GKRS.
Corbin A. Helis, Emory McTyre, Michael T. Munley, J. Daniel Bourland, John T. Lucas Jr., Christina K. Cramer, Stephen B. Tatter, Adrian W. Laxton and Michael D. Chan
A small subset of patients with trigeminal neuralgia (TN) will experience bilateral symptoms. Treatment in these patients is controversial because the population is heterogeneous and patients may have nonvascular etiologies of their pain. This study reports treatment outcomes in the largest cohort of patients with bilateral TN who have undergone Gamma Knife radiosurgery (GKRS) to date.
A retrospective chart review identified 51 individual nerves in 34 patients with bilateral TN who were treated with GKRS at the authors’ institution between 2001 and 2015, with 12 nerves in 11 patients undergoing repeat GKRS for recurrent or persistent symptoms. Long-term follow-up was obtained by telephone interview. Pain outcomes were measured using the Barrow Neurological Institute (BNI) pain scale, with BNI IIIb or better considered a successful treatment.
There was sufficient follow-up to determine treatment outcomes for 48 individual nerves in 33 patients. Of these nerves, 42 (88%) achieved at least BNI IIIb pain relief. The median duration of pain relief was 1.9 years, and 1-, 3-, and 5-year pain relief rates were 64%, 44%, and 44%, respectively. No patients experienced bothersome facial numbness, and 1 case of anesthesia dolorosa and 2 cases of corneal dryness were reported. Patients with a history of definite or possible multiple sclerosis were significantly more likely to experience BNI IV–V relapse. There was no statistically significant difference in treatment outcomes between patients in this series versus a large cohort of patients with unilateral TN treated at the authors’ institution. There was sufficient follow-up to determine treatment outcomes for 11 individual nerves in 10 patients treated with repeat GKRS. Ten nerves (91%) improved to at least BNI IIIb after treatment. The median duration of pain relief was 2.8 years, with 1-, 3-, and 5-year rates of pain relief of 79%, 53%, and 53%, respectively. There was no statistically significant difference in outcomes between initial and repeat GKRS. One case of bothersome facial numbness and 1 case of corneal dryness were reported, with no patients developing anesthesia dolorosa with retreatment.
GKRS is a safe, well-tolerated treatment for patients with medically refractory bilateral TN. Efficacy of treatment appears similar to that in patients with unilateral TN. GKRS can be safely repeated in this population if necessary.