A chronic anal fissure is a non-healing linear tear in the
distal anal mucosa below the dentate line. Where acute
fissures usually heal spontaneously, chronic fissures
are unlikely to heal with conservative therapy. A chronic
fissure can be morphologically identified by the
presence of indurated edges, hypertrophy of the anal
papilla, a sentinel skin tag, exposed internal sphincter
muscle at the base of the fissure
6,9. Patients present
with anal pain commonly during defaecation and/or
rectal bleeding. The most common symptoms in our
series were rectal bleeding, constipation and pain during
or after defaecation. Most fissures occur in the
posterior midline; this may be anatomically related as
there is a lack of tissue support posteriorly within the
anal canal
10. In our series all of the selected patients
had posterior midline fissures. It has been estimated
that chronic anal fissure afflicts about 10% of the patients
who come to colorectal clinics, with both sexes
affected equally
2. In our series the number of females
were more than males in both groups. There was no
significant difference between the groups regarding the
age.
LIS is an effective treatment option but it carries
potential complications including anal incontinence3,5,6. LIS is considered the surgical treatment of choice
for only the patients unresponsive to medical management2,6,11,12. Developments in the understanding
of the physiology of internal anal sphinchter have resulted
in more conservative treatment options instead
of surgery1,3. Glyceryltrinitrate, diltiazem and Botulinum
Toxin A (BTX-A) are the most common
pharmacological treatment options1,3. Chemical
sphincterotomy, using BTX-A has become one of the
most popular first-line medical treatment option. It
offers reducing internal anal sphincter pressure without
the risk of incontinence13. BTX-A is produced by
Clostridium botulinum and is a potent neurotoxin. It
blocks synaptic release of acetylcholine and causes a
severe paralysis muscles. Jost and Schimrigk reported for the first time the treatment of anal fissures with
BTX-A14. There is no consensus on dosage, precise site of administration,
and number of injections6,9,12,15-18. In this
study we achieved 61.1% healing rate after injection of
20 U BTX-A to internal anal sphincter at the anterior
side of the anal canal. BTX-A injection has risk of
complications like transient anal incontinence, epididimitis,
hematoma, prolapsus of hemorrhoids. Fissure
recurrence is a serious problem and repeated BTX-A
injections can be performed5,10,12. In this study
we did not have any complications related to BTX-A
injection. It may be due to relatively low dose usage of
BTX-A, compared with the other studies in the literature.
Botulinum toxin heals only approximately 50-
65% of glyceryl trinitrate-resistant chronic anal fissures,
perhaps because chemical sphincterotomy alone
treats internal sphincter spasm but not chronic fissure
fibrosis7,8,10. Healing rates for BTX-A injection
for anal fissure may be improved if combined with
fissurectomy. It has been reported that, fissurectomy
with or without advancement flaps are also effective
options for chronic anal fissure with low incidence of
complications related to LIS1,6,19. There are reports
about different combinations of both surgical and
medical treatment modalities including the combination
of BTX-A injection with fissurectomy5,12,13,15,20-23. In this study with combination of BTX-A
with fissurectomy we achieved 77.8% healing rate.
Significant symptomatic improvement was seen in both
groups on 2nd and 4th weeks compared to pretreatment
period, but the difference between the two treatment
groups was not significant. The only postprocedural
problem was pain after fissurectomy procedures. There
were no complications related to fissurectomy.
In conclusion, although BTX A injection is an effective
and safe treatment option in patients with a
posterior chronic anal fissure non-responsive to other
medical treatments, combining it with fissurectomy
does not increase the healing rate.