The current TAMIS platforms allow use of both 5 and10 mm devices. Once the port is placed, standard laparoscopic instruments, including graspers, thermal energy devices, and needle drives, can be used to perform the procedure. A 5 mm 30 or 45° angled camera lens or flexible tip camera is inserted, and triangulation of the instrument facilitates the surgical dissection.

Resection using TAMIS is typically performed by demarcating the perimeter of the lesion, providing an appropriate margin (Fig. 20.2 ). This is done using electrocautery . This step is key to assure not only adequate margins but to keep from excess dissection.

The specimen may be tented gently using a grasper and electrocautery on a spatula tip or needle tip allows for full-thickness excision. We recommend beginning with the distal margin and dissecting proximally in order to avoid obscuring the view during dissection (Fig. 20.3 ). Importantly, the CO₂ insufflation provides a natural “pneumo-dissection,” thereby augmenting the ease and clarity of local excision using TAMIS. Using this approach, TAMIS permits for margin-negative full-thickness local excision and allows for a portion of the mesorectum to be removed en bloc with the specimen in the majority of cases (Fig. 20.4). Once the excision has been completed, it can be retrieved by removing the SILS port, or by simply removing the lid of the GelPOINT path platform. Depending on surgeon discretion, the specimen may be sent to pathology intraoperatively, so that clear margins can be established.

Next, the TAMIS platform is reintroduced and suturing of the rectal wall defect is performed, typically with absorbable suture. Securing knots intraluminally is done with the help of a standard knot pusher or metal split shots. Alternatively, automated suturing devices such as the EndoStitch (Covidien) or RD 180 (LSI Solutions) can be used to perform endoluminal suturing. When coupled with Lapra-TY (Ethicon) or 5 mm TK (LSI Solutions), the suture can be secured without intraluminal knot tying (Fig. 20.5 ). Generally, it is preferred to close the rectal wall defects after excision and this should be done transversely to prevent luminal narrowing. After completion of suturing, we often rinse the surgical site with a Betadine-containing fluid for additional antimicrobial effect (Fig. 20.6).