Unusual Complications of Acute Frontal Rhinosinusitis. Two Clinical Cases

Introduction: Acute frontal rhinosinusitis is defined as an acute infection of the frontal sinus. Spreading of this infection to surrounding structures is uncommon but, when present, carries significant morbidity and mortality. Description: In this case report, we present two unusual cases of frontal rhinosinusitis complications. Firstly, we describe a case of acute rhinosinusitis with orbital complications caused by a frontoethmoidal osteoma. In the second case, the infection extended to the underlying bone and through the skull causing osteomyelitis and focal meningitis complicated with an abscess. After appropriate treatment, both patients were free of infection at follow-up, without complications. Discussion: In the first case we presented, a frontoethmoidal osteoma gave rise to rhinosinusitis with orbital complications. These benign tumors rarely cause symptoms, but when large enough, sinus outflow can be blocked, making the osteoma clinically relevant. Osteomas can induce frontal rhinosinusitis, giving rise, among other conditions, to the development of orbital complications like periorbital cellulitis or the formation of a periorbital abscess. Diagnosis of osteoma is usually straightforward on computed tomography and surgical treatment is only indicated for large tumors, rapid growth, intracranial or orbitary extension. In the second clinical case, the infection extended to the underlying bone and through the skull causing osteomyelitis and focal meningitis with abscess formation. In this patient, a Draf Type IIa procedure was performed for the frontal abscess drainage, followed by proper antibiotic and anti-inflammatory therapy. Conclusions: Complications of frontal rhinosinusitis are uncommon but require immediate attention and aggressive treatment to avoid morbidity and mortality. In these cases, our patients were properly treated with good outcomes, avoiding potentially more dangerous complications.