Transcaruncular Approach With Orbital Protection for Resection of Sinonasal Lesions: How I do it

Patient 1

A 53-year-old male presented with biopsy-proven squamous cell carcinoma of the ethmoid sinuses. Imaging showed a right nasal cavity mass with thinning of the right cribriform plate (Figure 1A) and lamina papyracea (Figure 1B) with concern for lacrimal sac involvement (Figure 1C).

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Figure 1.

Computed tomography demonstrating potential thinning at the right cribriform plate in (A, red arrow) versus volume averaging and demineralization of the lamina papyracea with concern for extension of disease into the periorbital tissue (B, red arrow). Axial T1 postcontrasted magnetic resonance image slice depicting soft tissue involvement abutting the lacrimal sac (C, red arrow).

Patient 2

A 21-year-old female presented with progressive right-sided headaches with nasal endoscopy notable for a submucosal mass in the frontal recess. Imaging demonstrated a large mixed fibrous and osseous lesion within the right frontal recess with extension into the right frontal and anterior ethmoid cells with lateral bulging into the medial orbit consistent with an osteoma (Figure 2).

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Figure 2.

Coronal (A) computed tomography (CT) demonstrates large right sinonasal osteoma with apparent deformity of the right medial orbital wall (arrows) with mass effect on orbital structures. Axial slice (B) noting area of palpable bony protuberance to medial orbit palpated on examination (arrow). Sagittal cut through right paranasal sinuses demonstrating near complete filling of frontal sinus and anterior ethmoid involvement (C) by osteoma with broadly based skull base attachment (arrows).

Surgical Technique

To perform the transcaruncular approach, an incision is made through the lateral 1/3 of the caruncle and extended superiorly/inferiorly to the level of the upper/lower puncta. The retrocaruncular fascia is entered and dissection is carried medially, accessing the medial orbital wall just posterior to Horner's muscle at the level of the posterior lacrimal crest. During dissection, it is important to remain within this plane to minimize the risk of injury to nearby structures, particularly the lacrimal system. Once the posterior lacrimal crest is visualized, dissection is performed in either a supra- or subperiosteal plane. The AEA is encountered ∼24 mm posterior to the anterior lacrimal crest.

In patient case 1, a transcaruncular incision was made to allow access to the medial wall of the orbit (Figure 3A). The AEA was identified, cauterized, and divided (Figure 3B). Tumor was then dissected away from the medial wall of the orbit and lacrimal sac. A dacryocystectomy (DCR) was performed and negative frozen margins were obtained. Should the nasolacrimal sac been positive for tumor, a medial maxillectomy with removal of the intraosseous nasolacrimal duct would have been performed. A nylon sheet and green shield were placed between the orbit and tumor tissue/medial orbital wall to aid in protecting the orbit and visualizing orbital boundaries during the sinonasal resection (Figure 3C).

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Figure 3.

(A) The initial transcaruncular incision beginning at the lateral 1/3 of the caruncle and carried posteriorly. The anterior ethmoid artery is then encountered (B, black arrow) that is controlled by bipolar electrocautery and sharply divided. Once dissection is completed and tumor separated from the orbital contents, we recommend simultaneous placement of the nylon sheet (C, white arrow) that will be used for reconstruction and green shield (C, black arrow) placement to provide a visual barrier for subsequent endonasal dissection. (D) An endonasal view with a 70-degree endoscope. The remnant of the anterior ethmoidal artery is denoted by the white arrow with the frontal sinus at the white star. Note the visible green shield separating the orbital contents for safer dissection.

During endonasal resection, the protective shield was readily visible, preventing prolapse of orbital fat into the surgical field and safeguarding the orbital contents (Figure 3D). Following tumor resection, a transconjunctival DCR was performed through the same incision. The nylon sheet was repositioned within the bony orbital defect, with stable bone on all edges and seated within the subperiosteal space to reconstruct the orbital floor and medial wall. Forced ductions were performed followed by medial canthal and conjunctival reconstruction. The medial canthus was secured to stable tissue in the posterior superomedial direction to prevent telecanthus with 5-0 polyglactin suture and the caruncle closed with 6-0 fast gut.

For patient 2, an identical initial approach was performed. To further aid in resection, the periorbita with overlying shield was retracted laterally to facilitate osteoma thinning and removal. A modified Lothrop was then performed, and the remainder of the tumor was removed.