Background: we previously assessed the efficacy of different medical and surgical treatments for chronic anal fissure (CAF). In this prospective audit we present longer-term results of this study in a larger series.Patients and Methods: From 01/04 to 09/08, 294 patients with typical CAF were enrolled. All patients were treated with 0.2% nitroglycerin ointment (GTN) or anal dilators (DIL) for 8 weeks. Those patients in which no improvement in symptoms was observed after 8 weeks were crossed to the other treatment (GTN or DIL) or switched to a combination of the two. Persisting symptoms after 12 weeks or recurrence were indications for either botulinum toxin injection into the internal sphincter and fissurectomy (BTX) or LIS. Primary end-point was fissure healing at last follow-up. Secondary end-points were symptomatic improvement, need for lateral internal sphincterotomy (LIS), and side effects. Differences between treatment groups were evaluated by chi square test. Results: patients' demographics, fissure characteristics and treatment results are resumed in Table 1. Mean follow-up was 36±17 months. Recurrence rate after 12 weeks treatment was similar between GTN and DIL (11.5% vs 9.3%). Overall fissure healing after medical treatment was 69.7% without significant differences between GTN (57.2%), DIL (66.9%) or a combination of the two (59.5%). Side effects (GTN) or severe discomfort (DIL) were observed in 13.2% of the patients. Thirty patients were treated with BTX and 64 underwent LIS (including BTX failures). At the end of the follow-up healing rates were 83.3% after BTX and 100% after LIS. No morbidity or postoperative incontinence were observed in both surgical groups.Conclusions: This study confirms that LIS is far more effective than medical treatments for CAF. However, BTX injection/fissurectomy as first line treatment may significantly increase the healing rate while avoiding any risk of incontinence.
Table 1: patients' demographics, fissure characteristics and treatment results.

	GTN	DIL	GTN/DIL	BTX/Fissurectomy	LIS
Number	173	121	42	30	64
Mean Age (years)	41	43	43	38	45
Sex (M/F)	80/93	52/69	28/14	11/19	27/32
Fissure position
Ant	19	18	8	2	15
Post	145	97	32	26	47
Both/other	9	6	2	2	2
Single treatment (12 weeks) success N/%	95/173 (54.9%)	75/121 (61%)	NA	NA	NA
Recurrence	11/95 (11.5%)	7/75 (9.3%)	NA	NA	NA
After cross-over healing N/%	20/50 (40%)	16/32 (50%)	17/42 (40.4%)	NA	NA
Recurrence	5/20 (25%)	3/16 (18.7%)	4/17 (23.5%)	NA	NA
Overall success N/%	99/173 (57.2%)	81/121 (66.9%)	25/42 (59.5%)	25/30 (83.3%)	64/64 (100%)

NA= not applicable