"Qué hay de nuevo""Osseous Remodeling Technique of the Sella Turcica: A New Surgical Option for Primary Empty Sella Syndrome" / "What's new ""Osseous Remodeling Technique of the Sella Turcica: A New Surgical Option for Primary Empty Sella Syndrome"

La silla turca vacía (STV) o como se la denominó más recientemente, aracnoidocele selar, es una entidad clínico-radiológica con una prevalencia que, si bien no se conoce con exactitud, se estima que es entre el 2 al 20%1. Dos tipos de STV han sido descriptas según su etiología: primaria y secundaria. En la primaria, no existe antecedente de cirugía hipofisaria previa y se cree que se produce debido a un diafragma selar deficiente. Por otro lado, cuando se genera luego de la exéresis de un tumor hipofisario se denomina secundaria. Por lo general, la STV primaria es diagnosticada como un hallazgo incidental en resonancia magnética, en donde se evidencia una herniación aracnoidea y de líquido cefalorraquídeo (LCR) a través del diafragma selar, comprimiendo la glándula hipofisiaria contra el piso de la silla turca. Algunos pacientes pueden manifestar síntomas clínicos (síndrome de silla turca vacía), entre ellos, cefalea, alteraciones endocrinológicas, fístula de LCR y alteraciones visuales. La cirugía está indicada en estas dos últimas manifestaciones

Osseous Remodeling Technique of the Sella Turcica: A New Surgical Option for Primary Empty Sella Syndrome.

BACKGROUND: Empty sella is an anatomic finding that is usually asymptomatic. However, when patients with empty sella finding present with visual deficits, surgical treatment may be necessary. The main goal of surgery is to elevate sellar content through a transsphenoidal approach. The aim of this study was to demonstrate a new technique for precise reconstruction of the sellar floor using a heterologous bone block to restore the anatomic elements of the sella turcica. METHODS: Three patients with primary empty sella who presented with visual field defects were prospectively included. Surgery was performed through a microsurgical transsphenoidal approach and involved elevating the sellar content by using a tricortical heterologous bone graft, the dimensions of which were obtained considering the exact dimensions of each patient's sella turcica. The graft was premodeled outside the surgical bed and carefully introduced into the sella turcica to achieve the required elevation (chiasmapexy). RESULTS: Vision of all 3 patients improved, and the improvement persisted throughout the follow-up period. 2 patients, this improvement was noted immediately after surgery, and in the third patient, this change in vision occurred 1 week later. Long-term imaging studies showed the persistence of the bone graft in the sella turcica and the exact elevation of the sellar content at the end of the follow-up period. There were no complications in the present series. CONCLUSIONS: The technique presented here is simple and reproducible and allows an almost exact and persistent elevation of the sellar content.

Gamma knife radiosurgery for benign tumors with symptoms from brainstem compression.

PURPOSE: This study evaluated the role of radiosurgery in the management of symptomatic patients with brainstem compression from benign basal tumors. METHODS AND MATERIALS: Over a 17-year, period 246 patients (202 vestibular schwannomas and 44 meningiomas) with brainstem compression from benign skull-base tumors were managed with Gamma Knife radiosurgery. Median tumor volumes were 3.9 cm(3) (range, 0.8-39.0 mL) and 6.6 mL (range, 1.6-25.1 mL) for vestibular schwannomas and meningiomas, respectively. For both tumors, a median marginal dose of 13 Gy was prescribed. Median follow-up of patients was 65 months for vestibular schwannomas and 60 months for meningiomas. Patients were categorized into four groups on the basis of the tumor-brainstem relationship on neuroimaging. RESULTS: Preservation of function was stratified according to grade of brainstem compression. We analyzed the effect of radiosurgery on symptoms of brainstem compression. The tumor control rate was 100 % for meningioma and 97% for vestibular schwannomas (although 5% required an additional procedure such as a ventriculoperitoneal shunt). In patients with vestibular schwannoma, serviceable hearing was preserved in 72.0%. Balance improved in 31.9%, remained unchanged in 56.5%, and deteriorated in 11.6% of patients who had imbalance at presentation. Balance improved significantly in patients who had less tumor compression (p = 0.0357) after radiosurgery. Symptoms improved in 43.2% of patients with meningioma. CONCLUSION: Radiosurgery is a minimally invasive option for patients with benign basal tumors that indent or distort the brainstem. A high tumor growth control rate and satisfactory rate of neurological preservation and symptom control can be obtained with radiosurgery.

Gamma knife radiosurgery for trigeminal schwannomas.

BACKGROUND: Trigeminal schwannomas are uncommon tumors that may be microsurgically removed in selected cases, albeit with significant risk for new neurological morbidity. We evaluated the role of stereotactic radiosurgery as an alternative for patients with newly diagnosed or residual trigeminal schwannomas. METHODS: The records of 23 patients who underwent radiosurgery for trigeminal schwannoma were reviewed. The most frequent presenting symptoms were facial numbness (11 patients), diplopia (6 patients), and facial pain (3 patients). One patient presented with partial complex seizures as the first symptom. Twelve patients had undergone one or more prior resections. Eleven underwent radiosurgery on the basis of imaging diagnosis only. The mean tumor volume was 4.5 mL (range 0.46-11.2 cc). Radiosurgery was performed using a median marginal dose of 15 Gy (range, 13-20 Gy). RESULTS: At a median imaging follow-up of 40 months (range, 12-146), 20 of 22 evaluable patients (91%) had tumor growth control (regression in 15 and no further tumor growth in 5). One 80-year-old patient died of unrelated cause 4 months after radiosurgery. Two patients with enlarged tumors were treated effectively with repeat radiosurgery. Twelve of 23 patients (52%) reported improvement and 9 (39%) had no change in their symptoms. Two patients noted new neurological complaints (transient facial weakness in 1 patient and worsening of the preradiosurgery facial numbness in another patient). CONCLUSIONS: Radiosurgery is an effective minimally invasive management option for patients with residual or newly diagnosed trigeminal schwannomas.

Primary empty sella syndrome: the role of visual system herniation.

BACKGROUND: It has been traditionally accepted that ophthalmologic alterations in cases of primary empty sella syndrome are caused by the herniation of the visual system in the pituitary fossa, but this cannot be stated categorically. METHODS: Two female patients with primary empty sella syndrome and visual field defects were included in this series. The peculiarity of these cases was that in neither of them was there an evident herniation of the visual system. In the absence of other causes that could explain the visual defects, the patients were operated on through a transsphenoidal approach. RESULTS: Both patients showed immediate improvement of their visual deficits without recurrence. Postoperative imaging studies have shown continuance of an adequate elevation of the sellar contents during the 5-year follow-up period. CONCLUSIONS: Visual field defects in cases of primary empty sella syndrome may occur even without radiological evidence of herniation of the visual system. The fact that the two patients described in this paper improved after surgery supports other reports that in this syndrome traction on the infundibular stalk may cause some microscopic anatomic alteration in the visual system or in its vascular supply that is not evident on imaging studies.