Abdominal distension after eating lettuce: The role of intestinal gas evaluated in vitro and by abdominal CT imaging.

BACKGROUND: Some patients complain that eating lettuce, gives them gas and abdominal distention. Our aim was to determine to what extent the patients' assertion is sustained by evidence. METHODS: An in vitro study measured the amount of gas produced during the process of fermentation by a preparation of human colonic microbiota (n = 3) of predigested lettuce, as compared to beans, a high gas-releasing substrate, to meat, a low gas-releasing substrate, and to a nutrient-free negative control. A clinical study in patients complaining of abdominal distention after eating lettuce (n = 12) measured the amount of intestinal gas and the morphometric configuration of the abdominal cavity in abdominal CT scans during an episode of lettuce-induced distension as compared to basal conditions. KEY RESULTS: Gas production by microbiota fermentation of lettuce in vitro was similar to that of meat (P = .44), lower than that of beans (by 78 ± 15%; P < .001) and higher than with the nutrient-free control (by 25 ± 19%; P = .05). Patients complaining of abdominal distension after eating lettuce exhibited an increase in girth (35 ± 3 mm larger than basal; P < .001) without significant increase in colonic gas content (39 ± 4 mL increase; P = .071); abdominal distension was related to a descent of the diaphragm (by 7 ± 3 mm; P = .027) with redistribution of normal abdominal contents. CONCLUSION AND INFERENCES: Lettuce is a low gas-releasing substrate for microbiota fermentation and lettuce-induced abdominal distension is produced by an uncoordinated activity of the abdominal walls. Correction of the somatic response might be more effective than the current dietary restriction strategy.

Cross-linking and intracorneal ring segments--review of the literature.

OBJECTIVES: To review and summarize relevant studies on combined use of corneal crosslinking and intracorneal ring segments (ICRS) for the treatment of corneal ectasia. METHODS: A literature search was performed using the key words "corneal collagen cross-linking" and "intra-corneal ring segments." RESULTS: Crosslinking is a well-accepted treatment option for corneal ectasia and can be combined with corneal ICRS insertion as needed. The advent of crosslinking has dramatically reduced the number of corneal transplants performed for patients with keratoconus or postrefractive ectasia. Intracorneal ring segments, although flatten the corneal surface, do not prevent the progression of corneal ectasia. This is why the combination of crosslinking and ICRS is potentially synergistic. Previous studies reported that combining these two complementary interventions has been shown to be safe and effective. CONCLUSIONS: The effects of ICRS are enhanced and stabilized by crosslinking, but the ideal combined technique is not known at present.

Which bowel preparation is best? Comparison of a high-fibre diet leaflet, daily microenema and no preparation in prostate cancer patients treated with radical radiotherapy to assess the effect on planned target volume shifts due to rectal distension.

OBJECTIVE: We evaluated and compared a high-fibre diet leaflet, daily microenema and no preparation to establish how best to achieve consistent bowel preparation in prostate cancer patients being treated with radical radiotherapy. METHODS: 3 cohorts of 10 patients had different dietary interventions: no bowel preparation, high-fibre diet information leaflet and daily microenemas. The available cone beam CT (CBCT) scans of each patient were used to quantify interfractional changes in rectal distension (measured using average cross-sectional area-CSA), prostate shifts relative to bony anatomy compared with that at CT planning scan and rates of geometric miss (i.e. shifts of ≥5 mm). 85 CBCT scans were available in the pre-leaflet cohort, 89 scans in the post-leaflet, and 89 scans in the post-enema group. RESULTS: Mean rectal CSA in the post-enema group was reduced compared with both pre-leaflet (p=0.010) and post-leaflet values (p=0.031). The magnitude of observed mean prostate shifts was significantly reduced in the post-enema group compared with the pre-leaflet group (p=0.014). The proportion of scans showing geometric miss (i.e. shift >5 mm) in the post-enema group (31%) was significantly lower than in the pre-leaflet (62%, p<0.001) or post-leaflet groups (56%, p<0.001). CONCLUSION: This study indicates microenema to be an effective measure to achieve reduction in rectal CSA, prostate shift and reduce geometric miss of ≥5 mm. A further prospective randomised study is advocated to validate the results. ADVANCES IN KNOWLEDGE: The use of microenema is effective in reducing prostate shift and rectal CSA, consequently decreasing the incidence of geographical miss.

Post-LASIK keratectasia triggered by eye rubbing and treated with topography-guided ablation and collagen cross-linking--a case report.

PURPOSE: To report a case of unilateral post-laser-assisted in situ keratomileusis (LASIK) keratectasia in a 35-year-old woman who had no known predisposing risk factors but who rubbed her affected eye frequently and vigorously in response to allergic conjunctivitis. METHODS: Case report with relevant literature review. RESULTS: A 35-year-old woman, with a cumulative risk scale score of 0 (according to the Randleman criteria), who underwent bilateral LASIK developed unilateral post-LASIK keratectasia 32 months later. She presented with a history of vigorous eye rubbing of the affected eye since about a year after allergic conjunctivitis. The fellow eye, which was not rubbed, remained normal. She complained of glare, halos, and ghost images in her affected eye. She underwent transepithelial topography-guided customized ablation with simultaneous UV-A corneal collagen cross-linking, after which she improved symptomatically and topographically. CONCLUSIONS: Eye rubbing could contribute to the development of keratectasia, even in an eye that has no subclinical features of the disease. When detected early, a simultaneous combined topography-guided customized ablation treatment and collagen cross-linking is effective in improving the irregular corneal contour and restoring biomechanical stability.

Clinical and histologic evaluation of psoriatic plaques treated with a flashlamp pulsed dye laser.

BACKGROUND: Psoriatic plaques can be cleared by destruction of the dermal papillae. Dilated vessels, the major component of psoriatic dermal papillae, can be selectively destroyed with yellow light lasers. Previous investigators have demonstrated partial clearing of psoriatic plaques after treatment with a pulsed dye laser (PDL) (585 nm). OBJECTIVE: This study was designed to examine the clinical and histologic events of psoriasis treated with the PDL. METHODS: Psoriatic plaques were treated with a short (450 microseconds) and long (1500 microseconds) pulse-width PDL. Photographs of the plaques were used for clinical assessment. Biopsy specimens were examined microscopically. RESULTS: Significant clinical improvement was seen, and no significant difference between the long and short pulse-width lasers was found. Patients responding to treatment with the PDL remained in remission for up to 13 months. Histologic normalization occurred after treatment. Two pretreatment vascular patterns were seen: vertically oriented vessels with few horizontal vessels and numerous tortuous vessels. Tortuous vessels were associated with poor clinical results. CONCLUSION: The PDL can induce prolonged remission in chronic plaque psoriasis. The vascular pattern may help to distinguish those patients likely to respond to this treatment.