Page 23 - Clinical Manual of Small Animal Endosurgery

Rigid Endoscopy 11

Specialised instrumentation

Basic rigid-endoscopy sets can be used for different applications, such as
rhinoscopy, cystoscopy and video-otoscopy. More specialised procedures
(arthroscopy, laparoscopy and thoracoscopy) are also possible, but require
larger investments in equipment and time (due to the steep learning curve).
Instrumentation typically used for video-otoscopy – besides the stand-
ard video system – are small-diameter rigid endoscopes (18 cm long, 1.9
or 2.7 mm diameter) with a 0 or 30° viewing angle. These are inserted
into specialised video-otoscopic cones, or into cystoscope or arthroscope
sheaths, which provide an irrigation channel. In anaesthetised animals,
fluids are used to provide an optical space and ensure complete cleansing
and examination.
Cystoscope sheaths have a rounded tip, and have the advantage of
also having an outflow and an operating channel, which is useful for the
insertion of forceps (for biopsies and removal of foreign bodies), and of
curettes and ear loops. These instruments, as well as suction and cath-
eters for flushing, can otherwise be inserted along the scope.
The endoscope most useful in rhinoscopy is one with a 30° viewing
angle, 2.7 mm diameter and 18 cm in length (1.9 mm diameter/10 cm
length for cats and very small dogs), and can be used ‘naked’ or with a
cystoscopy or arthroscopy sheath, depending on the surgeon’s prefer-
ence. The advantage of using a sheath is the presence of irrigation and
– in cystoscopy sheaths – biopsy channels; however, the sheath increases
considerably the outer diameter of the endoscope, thus limiting its use
in smaller patients. Furthermore, the samples retrieved through the
biopsy channel are very small, and therefore this technique may produce
less reliable biopsy results. Biopsy samples are preferably to be collected
with 3 mm oval biopsy forceps, which allow collection of larger diagnos-
tic samples (Fig. 1.11). The forceps are inserted alongside the endoscope

Fig. 1.11 Cup biopsy forceps: these 3 mm oval biopsy forceps allow
collection of large diagnostic samples.