Assessing the effectiveness of laser fistulectomy for anal fistula: a retrospective cohort study.

BACKGROUND: Laser fistulectomy is a minimally invasive, sphincter-sparing procedure for treatment of anal fistula. In several studies, this method has been shown to be safe and effective, with reported success rates ranging from 40 to 88%. We hypothesized that with longer follow-up, these rates would decrease. METHODS: A retrospective case analysis assessing the effectiveness of laser fistulectomy in curing fistula-in-ano tracts within a cohort of patients at a single academic institution was conducted. All patients having laser ablation between March 2016 and July 2018 were analyzed. Cure of the fistula was determined by history and postoperative physical exam, and was defined as complete closure of fistula tract with resolution of symptoms. Secondary symptoms of fecal incontinence, infection, and pain were evaluated. RESULTS: Eighteen patients (10 males, mean age 41 ± 13 years) were analyzed. Transphincteric fistula was the most common type (67%, N = 12). The mean number of previous fistula procedures was 1.33 ± 1.64. There was a 22% (N = 4) success rate at an average postoperative follow-up period of 29 ± 8 months (range 18-46 months). Of those who failed, 64% (N = 9) had a subsequent fistula procedure. There were no cases of fecal incontinence, but 3 cases (17%) of postoperative infection were reported and 8 patients (44%) had a subjective increase in pain at first follow-up appointment. CONCLUSIONS: Our data showed a much higher failure rate of laser fistulectomy compared to those reported in the literature. However, the small sample size, a large amount of heterogeneity in our patient population with a mixture of fistula types present, and various laser techniques applied decreased the power of this study.

Dose-response of the cultured bovine lens to butyl, methyl and propyl parabens.

Pre-screening of cosmetic ingredients is vital for consumer safety. Previous in vivo techniques, such as the Draize test, have proved to be unreliable in predicting ocular irritancy and therefore there is a need for alternate testing methodologies. One such test is the scanning laser in vitro assay system which quantifies irritancy based on the focusing ability of the cultured bovine lens. In combination with confocal microscopy, a more thorough documentation of ocular irritancy can be achieved. This study investigates the response of cultured bovine lenses over time to butyl, methyl and propyl parabens, which are common antimicrobial agents found in cosmetic and ophthalmic products. The focusing ability of the lens was measured with an automated laser scanner over a period of 96 h. At 120 h post-treatment, the lenses were analysed by using a confocal laser scanning microscope to determine the characteristics of nuclei, and the morphology and distribution of mitochondria within the lenses. Irritancy to the three parabens was investigated at both an optical and cellular level. Each of the parabens was tested at 0.002% and 0.2%, where the 0.2% butyl paraben was found to be the most irritating.

Optical response of the cultured bovine lens; testing opaque or partially transparent semi-solid/solid common consumer hygiene products.

This study determines the relative ocular lens irritancy of 16 common partially transparent or non-transparent consumer hygiene products. The irritancy was found by measuring the changes in the sharpness of focus [referred to as the back vertex distance (BVD) variability] of the cultured bovine lens using a scanning laser In Vitro Assay System. This method consists of a laser beam that scans across the lens, and a computer, which then analyses the average focal length (mm), the BVD variability (mm), and the intensity of the beam transmitted. Lenses were exposed to the 16 hygiene products and the lens' focusing ability was monitored over 192 h. The products are semi-solids or solids (e.g. gels, lotions, shampoos). They are categorized into six groups: shampoos, body washes, lotions, toothpastes, deodorant, and anti-perspirant. Damage (measured by > 1 mm BVD variability) occurred slower for the shampoos, especially in the case of baby shampoo. The results indicate that shampoos exhibit the lowest level of ocular lens toxicity (irritability) while the deodorant is the most damaging.

Suppression of post-vitrectomy lens changes in the rabbit by novel benzopyranyl esters and amides.

This study reports for the first time a therapeutic modality for the suppression of posterior subcapsular cataract (PSC) formation in an animal model (rabbit) of vitrectomy. This therapeutic modality may also have the potential to attenuate/prevent the high incidence of loss of vision due to cataract formation in patients that undergo vitrectomy. Unilateral, partial vitrectomy was performed on 2.5 month old Dutch Belted rabbits with vitreous replaced by either commercially available BSS((R)) or BSS PLUS((R)) (n=16). Alternatively, vitreous was replaced with a proprietary, modified BSS PLUS((R)) irrigating solution containing 1.25 microM AL-8417 (n=12), 5.0 microM AL-12615 (n=5) or 5.0 microM AL-17052 (n=9). Age matched, non-operated rabbits were used as controls (n=16). Lenses were analysed by correlative structural (light, scanning electron microscopic and three-dimensional computer-assisted drawings) and optical (low power helium-neon laser scan) quality analysis 6 months following surgery. Results demonstrate that vitreous replacement with an irrigating solution that contains the ester-linked benzopyran, AL-8417, the amide-linked benzopyran pro-drug, AL-17052, or its active metabolite, AL-12615, prevented abnormal post-vitrectomy lens growth, or fiber formation. Focal length variability (FLV) assessments (sharpness of focus) confirmed the beneficial drug effects detected morphologically, with FLV being essentially equal to that of age-matched, non-surgical controls. In contrast, lenses of animals with vitreous replaced solely with BSS((R)) or BSS PLUS((R)) exhibited significantly higher FLV than both age-matched controls and animals that underwent vitrectomy with drug-containing irrigating solutions. The ability of AL-8417, AL-17052 and its active metabolite, AL-12615, to suppress vitrectomy-induced posterior lens fiber changes appears to reside in their unique pharmacological profile, acting as antioxidant, anti-inflammatory and cytostatic agents.