Many manufacturers produce hundreds of single use and reusable biopsy forceps, the following are the main types. There are two chief varieties of cold biopsy forceps, single bite and double bite. Double bite forceps are equipped with a needle spike between the opposing cups. This needle spike secures the first specimen on the needle during collection of a second (Fig. 7.5). Biopsy forceps with a needle also provide deeper biopsies than non-needle versions. Single bite cold biopsy forceps do not have a needle spike (Fig. 7.6). Biopsy cup jaws may be round, oval, or elongated, fenestrated or non-fenestrated, smooth, or serrated. Large capacity or “jumbo” biopsy forceps sample a larger volume of tissue, at least two times the surface area of standard size forceps, but they do not necessarily yield deeper specimens, and they require a larger diameter biopsy channel [6]. Multiple biopsy specimen forceps are also available. These are designed to obtain multiple specimens with a single pass. There is concern that the samples obtained with these forceps are too small for adequate diagnostic evaluation [7].

Polypectomy with hot biopsy forceps provides cautery via the two biopsy cups. There is concern regarding both adequate destruction of neoplastic tissue and also the possibility of transmural thermal injury [8]. Reports have shown that hot biopsy forceps may yield a deeper tissue injury than produced with a snare [9].

Polypectomy snares use a monopolar wire loop that is advanced through a plastic catheter with the intention of encircling the target tissue. The tissue is then transected by the means of mechanical and electrosurgical cutting as the loop is pulled back into the catheter. All snares can be used with electrocautery, but either hot or cold techniques can be employed. Snares are made of monofilament or braided wires of various gauges. Snares are made in loop sizes up to 60 mm and in a variety of shapes, designed to match the anatomic requirements for removing a given lesion (Fig. 7.7) [8].

Endoscopic tattooing is an essential practice in order to find a location in the bowel either at future endoscopy or during surgery. A tattoo is performed by injecting a solution submucosally using an endoscopic injection needle. Many injection needles are available; the most common are 22 or 25 gauge.

Many solutions including India ink, indocyanine green (ICG), methylene blue, indigo carmine, toluidine blue, isosulfan blue, hematoxylin, and eosin have been considered for endoscopic tattooing. Animal studies have shown that only India ink and ICG are seen at the injection site longer than 48 h [10].

India ink, used for writing in India since the fourth century BC, has been used for endoscopic tattooing since the 1970s. It is composed of a suspension of carbon particles in a solution of organic and inorganic substances. Various preparations exist which may contain numerous substances, which can cause local tissue reaction. Nonsterile India ink can be mixed with saline and made sterile by either autoclave or millipore filtration. A range of concentrations of India ink have been studied; undiluted and 1:10 dilution cause mucosal ulceration, a 1:100 produced no inflammation, and was seen at endoscopy and surgery for 5 months [11].

A sterile, biocompatible suspension, containing carbon particles known as Spot (GI Supply, Camp Hill, PA), was developed, and is specifically sold for endoscopic tattooing (Fig. 7.8). This product has been studied in 113 patients; it produced no signs or symptoms of inflammation. Ten of the patients underwent surgical resection; Spot was seen at the time of surgery in all cases; none of the specimens showed signs of necrosis or abscess formation. Forty-two of the patients underwent subsequent colonoscopy anywhere from 3 to 12 months from the time of tattooing; the Spot was seen in every case [12].

ICG is a dye originally used for in medical diagnostics. ICG is contraindicated in patients with allergy to iodine [13]. In a study of 39 patients, ICG was visible intraoperatively in all 29 patients having surgery within 8 days. However, in the remaining ten patients who underwent surgery more than 8 days after tattooing, staining was seen in only two patients [14].

EMR is a procedure whereby a sessile polyp is removed; typically, lesions larger than 2 cm are removed piecemeal. The technology required for this procedure depends on the technique being used. Many endoscopists that perform EMR pre-inject liquid into the submucosal plane; this lifts the lesion to facilitate its removal, provide a cushion to prevent cautery injury to the deeper layers of the bowel, and in the event that a submucosal injection does not result in lifting of the lesion; this may indicate that the lesion is invasive and should not be resected in this fashion, but rather by surgical resection. For injection-assisted EMR one must have an injection needle (as discussed previously in this chapter) and the desired solution for pre-injection (Fig. 7.8). For EMR normal saline is typically used; however, other solutions are commonly used for submucosal injection, we will discuss these in more depth in the endoscopic submucosal dissection (ESD) section. If the endoscopist is performing the “Inject-and-Cut” technique, the next instrument required will likely be an electrocautery snare to resect the tissue desired. For the “Inject-Lift-and-Cut” technique one requires a colonoscope with two working channels and a grasping forceps as well. Grasping forceps are available as single use or reusable, and there are many different tips to choose from. Examples are: three-prong, five-prong, alligator jaw, rat tooth, rat tooth/alligator jaw, rubber tip, V shaped, and many more (Figs. 7.9, 7.10, 7.11, 7.12, 7.13, 7.14, 7.15, and 7.16). Additionally, many endoscopists perform what is known as cap-assisted EMR. This also uses submucosal injection and then dedicated mucosectomy devices that use a cap which is affixed to the tip of the colonoscope. A cap is a single use device, which also comes equipped with a specially designed crescent-shaped snare (Fig. 7.17). The mucosa is then retracted into the cap, using suction, and the snare is closed to capture the lesion. The available cap-assisted mucosectomy devices vary based on the characteristics of the cap. There are flat (straight) or oblique tips, and soft or hard plastic tips (Figs. 7.18 and 7.19). Cap outer diameters come from 12.9 to 18 mm; different sizes are based on the size of the lesion being removed. Lastly, in ligation-assisted EMR, a standard variceal band ligation device is positioned over the target lesion, suction is then applied, and the band is deployed over the base of the lesion, and a standard electrocautery snare is used to resect the lesion beyond the band. A combination snare and multiband device is available from Cook Medical (Bloomington, IN) known as the Duette . This device is currently only approved for upper GI procedures. Once the tissue has been excised, it must now be removed, there are multiple tissue collection devices, examples are the US Endoscopy Roth Net and Poly-Pak, combination rotatable snare and Roth net, ConMed’s Standard Nakao spider net, and Boston Scientific’s Twister Plus, Rotatable Retrieval Device (Figs. 7.20, 7.21, and 7.22).