Neuro-ophthalmologic manifestations of benign anterior skull base lesions

Visual disturbance is a common presenting symptom of anterior skull base lesions. These lesions cause deterioration in visual acuity, restriction of the visual field, or reduction of ocular mobility. Common pathological entities that affect the skull base and involve vision include meningioma, pituitary adenoma, tumors of the bone, malignancy, and infection. Benign lesions are typically treated surgically with acceptable long-term results. In this article, we review the presentation, evaluation, and surgical treatment of patients with benign skull base lesions presenting with visual disturbance.

Significance of MRI changes after surgery of the skull base

Magnetic resonance (MR) imaging is commonly used in the followup of patients who have undergone surgical removal of tumors from the cranial base to assess the possibility of tumor recurrence, persistence, or surgical complications. Interpretations of this study must be cautious because postoperative enhanced signals are encountered frequently. Although technological improvements continue to enhance the usefulness of MR images for followup, problems remain in differentiating between fibrotic, reconstructive changes, and tumor recurrence. In this study, the hospital records and MR findings of 215 patients who had undergone skull base surgery were reviewed. The study was prompted by negative operative exploration in three patients in whom postoperative MR images strongly suggested tumor recurrence. One-year follow-up images were available in 174 patients. Of these, 94% showed signal enhancement on the 1-year follow-up study. Progressive changes were observed in 14% of patients. The correlation of preoperative MR findings and surgery, with regard to dural involvement, vascular involvement, cranial nerve infiltration, and extent of intracranial infiltration, was analyzed in 28 patients. Methods to facilitate the detection of tumor recurrence using MR images are reviewed.

Malignant tumors of the anterior cranial skull base

Malignant tumors of the anterior cranial skull base are still a challenge for radical surgical treatment. Several different techniques and approaches have been developed over the years and the results, with mortality rates over 50%, are still not encouraging. Here we present our results of an interdisciplinary, one-stage, neurohino transfronto-transbasal surgical approach in twelve patients with such tumors. The long-term survival rate in our patients is now 83% with a mean postoperative follow-up of 19.3 months. Two patients died due to early recurrencies and metastasis after 10 and 13 months after initial treatment and postoperative irradiation. Another five patients with a follow-up of 34.2 months have had tumor recurrencies diagnosed at 19.5 months postoperatively. These patients have survived their recurrent tumor for 14.7 months. Five patients, 41% of the whole group, have been living without evidence of tumor recurrence for between 2 and 35 months.