Ultra-low dose CT colonography with automatic tube current modulation and sinogram-affirmed iterative reconstruction: Effects on radiation exposure and image quality.

OBJECTIVE: To assess the radiation dose and image quality of ultra-low dose (ULD)-CT colonography (CTC) obtained with the combined use of automatic tube current (mAs) modulation with a quality reference mAs of 25 and sinogram-affirmed iterative reconstruction (SAFIRE), compared to low-dose (LD) CTC acquired with a quality reference mAs of 55 and reconstructed with filtered back projection (FBP). METHODS: Eighty-two patients underwent ULD-CTC acquisition in prone position and LD-CTC acquisition in supine position. Both ULD-CTC and LD-CTC protocols were compared in terms of radiation dose [weighted volume computed tomography dose index (CTDIvol ) and effective dose], image noise, image quality, and polyp detection. RESULTS: The mean effective dose of ULD-CTC was significantly lower than that of LD-CTC (0.98 and 2.69 mSv respectively, P < 0.0001) with an overall dose reduction of 63.2%. Image noise was comparable between ULD-CTC and LD-CTC (28.6 and 29.8 respectively, P = 0.09). There was no relevant difference when comparing image quality scores and polyp detection for both 2D and 3D images. CONCLUSION: ULD-CTC allows to significantly reduce the radiation dose without meaningful image quality degradation compared to LD-CTC.

Healing of experimental colonic anastomoses: effects of combined preoperative high-dose radiotherapy and intraperitoneal 5-fluorouracil.

To study the effects of preoperative radiochemotherapy (RCT) on the healing of colonic anastomosis, the rectosigmoid colon in male Wistar rats was irradiated up to an end dose of 41.6 Gy (RT) or sham-irradiated (SR). During the last 5 days of the irradiation schedule, 5-fluorouracil (5-FU) was administered intraperitoneally in either a high dose (20 mg/kg, chemotherapy-high dose [CH]) or a low dose (10 mg/kg, chemotherapy-low dose [CL]). Animals were randomly arranged into six groups: group I, control (SR + saline intraperitoneally); group II, RT only; group III, SR + CL; group IV, RT + CL; group V, SR + CH; group VI, RT + CH. Four days after RCT, a side-to-side anastomosis was constructed between the irradiated rectosigmoid and the nonirradiated caecum. Animals were killed 10 days postoperatively. No significant differences were found in the anastomotic bursting pressure or the bursting wall tension. In group VI, mitoses were less (P < 0.01) and mucosal ulceration was more (P = 0.03) pronounced compared to group I. Sclerotic arteries were seen in all irradiated groups and in animals that received high-dose 5-FU alone. 5-FU administration in high or low dose, with or without RT, induced more inflammation in the submucosa compared to controls (P < 0.05). Conclusively, RCT has no detrimental effect on the mechanical strength of colonic anastomosis in this rat model. However, RCT with high-dose 5-FU induces more histological alterations at the anastomotic site.

A case of persistent endometriosis after total hysterectomy with both salpingo-oophorectomy managed by radiation therapy.

Persistent endometriosis after total hysterectomy and both salpingo-oophorectomy (TH with BSO) is a rare condition and the etiology is uncertain. The exact incidence of persistent endometriosis after definitive surgery is not known. In addition, the treatment of persistent endometriosis after complete surgical excision is controversial. We report a case of persistent endometriosis with vaginal and sigmoid-colonic invasion after TH with BSO. The lesions were not responsive to hormonal therapy. The patient was managed successfully by therapeutic pelvic radiation.

Reno-colo-cutaneous fistula. A case report.

Reno-colo-cutaneous fistula due to genito-urinary tuberculosis is extremely rare. We describe one such case which was successfully managed by single stage surgery (nephroureterectomy, fistulectomy and primary repair of colon) and anti-tubercular treatment.

[Palliative treatment of colonic tumors with laser and afterloading irradiation]. / Palliative Behandlung von Kolontumoren mit Laser- und Afterloading-Bestrahlung.

Laser photoablation was undertaken in 46 patients (27 women and 19 men, mean age 81 [66-93] years) with malignant tumours of the colon, either for tumour bleeding (n = 7) or stenosis (n = 39), and in 27 patients combined with afterloading 192Ir irradiation. Operation had been refused by 14 patients, 22 were primarily inoperable, one received preoperative radiotherapy for ileus. The radiotherapy was inadequate in only one patient who had to be operated on for subileus. Eleven patients have had a mean survival time of 13.5 months, 22 died after a mean of 7.5 months. No patient died from ileus or any other complication of the palliative tumour treatment. These results suggest that combined laser and afterloading irradiation is an alternative treatment of malignant tumour of the lower intestinal tract or for patients who decline surgical treatment.