A projection by the superior colliculus to the supraoculomotor area (SOA) located dorsal to the oculomotor complex was first described in 1978. This projection’s targets have yet to be identified, although the initial study suggested that vertical gaze motoneuron dendrites might receive this input. Defining the tectal targets is complicated by the fact the SOA contains a number of different cell populations. In the present study, we used anterograde tracers to characterize collicular axonal arbors and retrograde tracers to label prospective SOA target populations in macaque monkeys. Close associations were not found with either superior or medial rectus motoneurons whose axons supply singly innervated muscle fibers. S-group motoneurons, which supply superior rectus multiply innervated muscle fibers, appeared to receive a very minor input, but C-group motoneurons, which supply medial rectus multiply innervated muscle fibers, received no input. A number of labeled boutons were observed in close association with SOA neurons projecting to the spinal cord, or the reticular formation in the pons and medulla. These descending output neurons are presumed to be peptidergic cells within the centrally projecting Edinger–Westphal population. It is possible the collicular input provides a signaling function for neurons in this population that serve roles in either stress responses, or in eating and drinking behavior. Finally, a number of close associations were observed between tectal terminals and levator palpebrae superioris motoneurons, suggesting the possibility that the superior colliculus provides a modest direct input for raising the eyelids during upward saccades.

Sebaceous carcinoma of the eyelid is an uncommon tumour with unusual modes of presentation. It can remain occult at the primary site, without producing any mass, masquerading as chronic blepharoconjunctivitis, while setting up metastases in the regional lymph nodesespecially in the pre-auricular group.

We report here a case that not only masqueraded as chronic blepharoconjunctivitis with nodal metastases from an ’unknown primary’ in the neck, but whose tumour spread in a pagetoid manner along the nasolacrimal duct producing a nasal tumour that was believed to be the ’unknown primary’.

This case emphasizes the need for ophthalmologists, ENT surgeons and pathologists to keep sebaceous carcinoma in mind while evaluating patients with chronic blepharoconjunctivitis and cervical node metastases from ’unknown primary’. Histological clues for picking up a sebaceous carcinoma at a metastatic site include a tumour with comedo or ductal growth pattern and intracytoplasmic lipid.