**10. Orbital exenteration with lateral wall removal**

This patient has right lateral canthal infiltrative basal cell carcinoma with lateral orbital wall invasion (**Figure 36**). He had been operated twice before and had also received radiotherapy as part of initial treatment. Coronal view CT scan revealed ill-defined soft tissue mass causing erosion of the lateral wall and infiltration of the orbit and globe (**Figure 37A** and **B**). The surgical plan is orbital exenteration with lateral wall removal along with surrounding soft tissues. Upper and lower lid incisions were marked 2 mm beyond eyelid margin with generous amount of skin and soft tissue kept attached to the eyelids at the lateral canthus to ensure satisfactory soft tissue margins (**Figure 38**). Superior lid, inferior lid and medial dissection is done similarly as described in first case, while laterally generous amount of soft tissues is left for safe margin attached to the specimen. Superiorly, medially and inferiorly subperiosteal dissection is done till the orbital apex as described for above cases. The surgical procedure needs a orbito-zygomatic cranial base exposure. A superior, lateral and inferior orbitectomy is done along with the removal of the zygomatic bone as shown on the skull (**Figure 39A** and **B**). Oscillating saw is used to make bone cuts from the superior orbital rim to superior orbital fissure posteriorly. Inferior cut is made from the inferior orbital rim to the inferior orbital fissure

#### **Figure 36.**

*A patient with a basal cell carcinoma of the right lateral canthus with extension into the orbit.*

#### **Figure 37.**

*(A) The coronal view of the CT scan shows ill-defined tumor involving the lateral quadrant of the right orbit with erosion of the lateral wall. (B) 3-D reconstruction of the orbit showing eroded lateral wall.*

#### **Figure 38.**

*Surgical plan of resection with generous amount of soft tissues kept on the lateral wall to achieve disease free margins.*

#### **Figure 39.**

*(A) Anterior view of the planned bone cuts outlined on a skull. (B) Right lateral view of the planned bone cuts outlined on a skull.*

posteriorly and zygomatico - temporal suture is divided. Small osteotomes are used to mobilize the surgical specimen after division of the surrounding soft tissues with electro- cautery. Diamond bur can be used to smoothen the bone edges. In a

#### **Figure 41.**

*(A) Anterior view of the surgical specimen shows en-bloc resection of the tumor with the contents of the orbit and the lateral soft tissues. (B) Posterior view of the surgical specimen shows en-bloc resection of the tumor with the contents of the orbit and the lateral soft tissues.*

**Figure 42.** *The skin incision is closed in layers.*

scenario of the erosion of the cranial base in the region, diamond bur can be used to remove the bone without causing tear in the dura. Even appropriate size Kerrison's punch can be used to remove the cranial base with adequate margins with out injuring dura. The surgical defect after removal of the specimen is examined for completion of surgery (**Figure 40**) and specimen can be sent for frozen section analysis of soft tissue margins. Anterior and posterior view of the specimen can be seen in the **Figure 41A** and **B**. In this particular case since enough of upper and lower eyelid flaps could be preserved, we could achieve primary closure (**Figure 42**).
