Diplopia as first symptom of a bronchogenic carcinoma

Background: Patients: In about 30% of patients with orbital metastases, these metastases are detected before the primary tumour is known. Cess than 5% of orbital metastases are located in extraocular muscles. We report on a patient with diplopia caused by diminished abduction of the left eye as first symptom of a bronchogenic carcinoma. Patient: A 86-year-old patient presented with a newly developed diplopia. On examination, the left eye showed a diminished abduction, ptosis and miosis. Pharmacological testing revealed peripheral Horner's syndrome. On cranial magnet resonance tomography, the lateral rectus muscle belly was enlarged. A chest X-ray showed a large tumour (6 cm in diameter) of the left upper robe with multiple metastases to the lungs. Further examinations revealed a large cell bronchogenic carcinoma with metastases to the lungs, adrenal glands, and the lateral rectus muscle. Conclusions: Diplopia caused by metastases to extraocular muscles is rare as first sign of a bronchogenic carcinoma. The combination of peripheral Horner's syndrome with diminished abduction of the homolateral eye primarily suggests a lesion of the cavernous sinus. The bronchogenic carcinoma could not be causative for Horner's syndrome in the patient presented here, however an undetected tumor-infiltration of the postganglionic region cannot be excluded. This case demonstrates that in all patients with newly developed diplopia and Horner's syndrome, even in absence of orbital signs, apart from a ophthalmological examination detailed radiographic or magnetic resonance tomographic imaging is necessary of both skull base and orbita.