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INTRODUÇÃOTumores da região da cabeça e pescoço são geralmente diagnosticados tardiamente, e a maior parte dos pacientes, no momento da detecção da lesão, apresenta estágio avançado da doença(1) . Tumores malignos das cavidades sinonasais podem se estender a locais críticos, essencialmente a órbita e o crânio . A anatomia complexa e compacta da órbita limita, muitas vezes, a extensão da ressecção cirúrgica (6,7). Por sua vez, neoplasias da base do crânio apresentam eleArtigo Original vada taxa de recorrência se a remoção cirúrgica não é completa (8) . Ambas as regiões geram dificuldades no posicionamento do campo radioterápico, e na tentativa de minimizar seqüelas actínicas estas áreas se tornam sítios comuns de disseminação tumoral por contigüidade, em conseqüência do emprego de campos radioterápicos conservadores (8) . A tomografia computadorizada (TC) e a ressonância magnética (RM) fornecem detalhada informação sobre cada área de comprometimento tumoral, auxiliando no estadiamento destas lesões (9-12) .
COMPROMETIMENTO ÓRBITO-CRANIANO POR TUMORES MALIGNOS SINONASAIS: ESTUDO POR
Sinonasal malignant tumors involvement of the orbit and skull: a computed tomography study.Malignant tumors of the sinonasal cavities are rare and often diagnosed late in the course of the disease. These tumors can extend into regions such as the orbit and brain, where treatment is difficult. Ten patients with nontreated sinonasal malignant neoplasms and radiological evidence of tumor extension into the orbit and brain were studied with computed tomography. Five (50%) tumors were epithelial neoplasms whereas squamous cell carcinoma was the most common type (3 cases). The ethmoidal sinus was the most common site of origin of the tumors (40%), followed by the maxillary sinus (30%) and nasal cavity (30%). A total of 16 orbits were involved since 6 patients (60%) had bilateral orbital involvement. The tumors extended more often into the orbits through erosion of the medial and inferior orbital bones. All orbital compartments were involved in the majority of the orbits. Tumoral extension into the cranial cavity was more common through the ethmoidal (70%) and orbital roof (30%). The anterior cranial fossa was involved in 8 cases (80%), followed by the medial cranial fossa (40%) and frontal lobe (excluding the anterior fossa) (30%). Thirty-seven regions of the face, other that the site of tumor origin, orbits and cranial cavity, were involved by the 10 tumors, indicating the extensive loco-regional disease at the time of diagnosis.