Experience of Surgical Approach to the Pontine Lesions - Report of 4 Cases -

뇌교병변의 수술적 접근에 대한 증례보고

Although direct surgical treatment of the lesion in the pons may cause severe neurologic morbidity, safe route to minimize injuries of the important structures in the pons should be considered. The authors operated four cases of intrapontine lesions via safe approach route without causing severe neurologic complications. Two cases were intrapontine tumors and other two were intrapontine hematoma. An anaplastic astrocytoma($3{\times}3{\times}3cm$) located bilaterally in the pons was approached via midline of the median sulcus, and a metastatic tumor($1.5{\times}1.5{\times}1.5cm$) located at the left posterolateral aspect in the upper pons was approached via suprafacial space. Two cases of hematoma were evacuated via median sulcus, and supra- and infrafacial spaces. Preoperatively, quadriplegia, swallowing difficulty, diplopia, speech disturbance, and nystagmus were noted in a patient with an anaplastic astrocytoma. A patient with metastatic tumor showed mild right hemiparesis, right hemisensory disturbance, diplopia, and dizziness. Two patients with hematoma in the pons were comatous, and had contracted, fixed pupils. Postoperatively, a patient with an anaplastic astrocytoma recovered and a patient with a metastatic tumor showed temporary hemifacial palsy. Mental status was fully recovered normal even though facial palsy, diplopia, severe ataxia, dizziness, and tremor persisted in both patients with pontine hematoma. Careful operation based on the anatomical knowledge of the floor of the 4th ventricle is of prime importance in appraoching to the intrapontine lesion with minimal injuries of the eloquent structures during surgery.