[Linear accelerator-based stereotactic radiosurgery for the treatment of trigeminal neuralgia. Nine years' experience in a single institution]. / Radiocirugia estereotactica con acelerador lineal para el tratamiento de la neuralgia trigeminal. Experiencia de nueve años en una sola institucion.

INTRODUCTION. Pharmacological treatment is the first therapeutic step towards controlling pain in trigeminal neuralgia, but 25-50% of patients become medication resistant. There are currently several surgical alternatives for treating these patients. AIM. To evaluate the effectiveness and safety of stereotactic radiosurgery for the treatment of patients with trigeminal neuralgia. PATIENTS AND METHODS. A follow-up study was conducted on 30 patients who underwent radiosurgery using a Novalis linear accelerator. Eighty per cent of the dosage was calculated at the isocentre, the entry zone of the root of the trigeminal nerve. The mean follow-up time was 27.5 months (range: 1-65 months). RESULTS. The mean age was 66 years (range: 36-87 years), with a time to progression of 7.1 years (range: 4-27 years). The distribution of the pain was from the right side (63.3%). Of the 30 patients, 27 experienced an improvement (90%) 1.6 months (range: 1 week-4 months) after the treatment; 10 patients (33.3%) scored grade I, and 17 patients (56.6%) obtained a score of grade II. During the follow-up, four patients (14.2%) suffered a relapse; two underwent re-irradiation. Time without recurrence was 62.7 months (range: 54.6-70.8 months). The rate of side effects was 76.7% and only three patients developed facial anaesthesia with loss of the corneal reflex. CONCLUSIONS. The use of the linear accelerator is an effective therapeutic option in the treatment of trigeminal neuralgia, since it provides adequate long-term control of the pain, reduces the use of medication and improves the quality of life.

TITLE: Radiocirugia estereotactica con acelerador lineal para el tratamiento de la neuralgia trigeminal. Experiencia de nueve años en una sola institucion.Introduccion. El tratamiento farmacologico constituye el primer escalon terapeutico para el control del dolor en la neuralgia del trigemino, pero entre el 25-50% de los pacientes se hace farmacorresistente. Actualmente existen varias alternativas quirurgicas para tratar a estos pacientes. Objetivo. Evaluar la efectividad y seguridad de la radiocirugia estereotactica para el tratamiento de pacientes con neuralgia del trigemino. Pacientes y metodos. Se dio seguimiento a 30 pacientes que se sometieron a radiocirugia con acelerador lineal Novalis. Se calculo el 80% de la dosis en el isocentro, la zona de raiz de entrada del nervio trigemino. El tiempo medio de seguimiento fue de 27,5 meses (rango: 1-65 meses). Resultados. La edad media fue de 66 años (rango: 36-87 años), con un tiempo de evolucion de 7,1 años (rango: 4-27 años). La distribucion del dolor fue del lado derecho (63,3%). De los 30 pacientes, 27 tuvieron mejoria (90%) 1,6 meses (rango: 1 semana-4 meses) despues del tratamiento; 10 pacientes (33,3%) tuvieron una valoracion de grado I y 17 pacientes (56,6%) una valoracion de grado II. Durante el seguimiento, cuatro pacientes (14,2%) tuvieron recidiva; dos se sometieron a reirradiacion. El tiempo sin recurrencia fue de 62,7 meses (rango: 54,6-70,8 meses). La tasa de efectos secundarios fue del 76,7%, y solo tres pacientes desarrollaron anestesia facial con perdida del reflejo corneal. Conclusiones. El uso del acelerador lineal es una opcion terapeutica efectiva en el tratamiento de la neuralgia del trigemino, proporciona a largo plazo adecuado control del dolor, reduce el uso de medicamentos y mejora la calidad de vida.

Trigeminal neuralgia is caused by maxillary and mandibular nerve entrapment: greater incidence of right-sided facial symptoms is due to the foramen rotundum and foramen ovale being narrower on the right side of the cranium.

Trigeminal neuralgia (TN) is the most important disease of the trigeminal nerve. Vascular compression of the dorsal root of the trigeminal nerve by aberrant loop of blood vessels is currently accepted as the most common cause of TN. The right side of the face is affected by TN twice as often as the left side, but there are no anatomical reasons for the blood vessels loop to be more frequent on the right side of the cranial fossa. Additionally, vascular compression in asymptomatic patients and in TN patients without aberrant blood vessels has been reported, thereby arguing against the idea that vascular compression alone is responsible for TN. Anatomical and radiological studies have shown that the rotundum and ovale foramens on the right side of the human cranium are significantly narrower than on the left side. The rotundum and ovale foramens are crossed by the maxillary and mandibular nerves, respectively, and are the nerves most affected in TN. Based on demographic and epidemiological data of TN patients, and on anatomical findings in the foramens, we hypothesized that entrapment of the maxillary and mandibular nerves when they cross the ovale and rotundum foramens is a primary cause of TN and accounts for the higher incidence of TN on the right sided.

Neuralgía esencial del trigémino, estudio retrospectivo de 64 casos / Esential trigeminal neuralgia: restrospective study of 64 cases

The Trigeminal Neuralgia, which is a non odontogenic pain, that takes place in the cranial-maxillofacial area, is a situation that the general dentist and tha maxillofacial surgeon, in particular, has to reconize. This study analizes 64 cases treated in period of 6 year. The epidemiologic results show several coincidences with international studies. They also show some characteristics not mentioned on the universal literature revised. The unique objective of this document is to determine the epidemiologics aspects of this desease, with respect to patients that attend spontaneously and/ or are derived from the others Services

Neuralgia del trigémino: revisión de la literatura / Trigeminal neuralgia: review of the literature

El presente trabajo realiza una revisión bibliográfica de las modalidades en el tratamiento de la neuralgia del trigémino en los últimos trece años

Cranial nerve length predicts the risk of delayed facial and trigeminal neuropathies after acoustic tumor stereotactic radiosurgery.

PURPOSE: To test the hypothesis that length of cranial nerve irradiated is a major factor predicting the risk of cranial nerve injury following radiosurgery and to identify any other significant related treatment factors. METHODS AND MATERIALS: Ninety-two patients (93 acoustic tumors) were treated with a 201 source Cobalt-60 gamma unit from 1987 to 1990 and prospectively followed. The range of minimum tumor dose was 12-20 Gy and maximum dose 24-50 Gy. Univariate and multivariate analyses were used to evaluate any correlations between tumor measurements and treatment factors, with the development of trigeminal and facial neuropathies following radiosurgery. RESULTS: The risks of trigeminal and facial neuropathy following radiosurgery were associated with the pon-petrous distance and mid porous transverse tumor diameters respectively (anatomically related to the irradiated length of cranial nerves V and VII respectively) in both univariate (p = .002 for V and p = .026 for VII) and multivariate (p = .004 for V and p = .055 for VII) analyses. Tumor volume, other tumor measurements, maximum dose, minimum tumor dose, and tumor dose inhomogeneity were not significantly related to either trigeminal or facial neuropathy in univariate and multivariate analyses. CONCLUSION: Within a minimum tumor dose range of 12-20 Gy, the incidence of delayed trigeminal or facial neuropathy depended more on the estimated length of nerve irradiated than the tumor dose or tumor volume. In the future, the risk of delayed facial or trigeminal cranial neuropathy may be reduced significantly by performing radiosurgery when the tumor still has both a small mid-porous transverse diameter and a small pons-petrous distance.