OBJECTIVETo explore the value of computed tomography colonography with low radiation dose combined with the enhanced scanning in the diagnosis of colorectal carcinoma.

METHODSA total of 120 patients with clinical suspected colorectal carcinoma undergoing CT colonography and enhanced scanning were randomly divided into routine dose group and low dose group. Conventional colonoscopy and/or surgical pathology were used as the gold standard. Sensitivity, specificity and Youden's index of colorectal cancer TNM staging accuracy were calculated in two groups. The radiation dose of two groups was compared.

RESULTSFor conventional dose and low dose group, in the diagnosis of colorectal cancer (including cancer and adenoma), the sensitivity was 100% (45/45 and 44/44), specificity was 93.3%(14/15) and 87.5%(14/16), the Youden's index was 0.93 and 0.88. There were no significant differences between two groups in T, N and M staging accuracy preoperatively (P>0.05). The effective radiation dose of low dose group was significantly lower than that of conventional dose group [(15.9 ± 4.3) mSv vs. (21.4 ± 5.5) mSv, P<0.01].

CONCLUSIONLow dose CTC combined with enhanced scanning not only reduces the radiation dose of patients, but can possesses similar value of conventional dose CTC in the early diagnosis and preoperative pathological staging of colorectal cancer.

Colonography, Computed Tomographic ; Colonoscopy ; Colorectal Neoplasms ; diagnostic imaging ; Humans ; Radiation Dosage

OBJECTIVEHearing impairment or loss is a common disorder at birth. Many perinatal conditions may also cause hearing impairment. The present study aimed at investigating the incidence and morbidity of hearing impairment in critically ill neonates with high risk factors in neonatal intensive care unit (NICU).

METHODSPatients were evaluated using the auditory brain-stem response (ABR) to detect hearing impairment or loss in 248 neonates stabilized or before discharge from the NICU during the period from Dec. 1999 to Aug. 2001 in SCMC. In this article, high risk factors of hearing loss included severe asphyxia, hyperbilirubinemia and very low birth weight, persistent pulmonary hypertension or on a ventilator, exposed to ototoxic medications such as aminoglycosides and diuretics, a family history of hearing loss, meningitis and craniofacial anomalies, etc. Screening test was performed with a 70 dB (SPL) hearing level click stimulus to each ear.

RESULTSSeventy-two newborns had detectable hearing impairment in all the patients studied, the incidence of hearing impairment was 29.03%. Among them 3 cases had serious hearing loss. Twenty cases were among the 50 asphyxiated newborns (40.0%); 24 were from the 91 neonates with hyperbilirubinemia (26.37%); 15 were from the 44 premature infant group (34.09%), three of 4 premature cases with birth weight less than 1 500 g had hearing impairment. Six cases were among the 15 newborns who used mechanical ventilation (40.0%); 19 cases were among the 46 newborns who received ototoxic agents (41.30%).

CONCLUSIONSCritically ill neonates with some specific high risk factors had a significantly high incidence of hearing impairment. Early hearing screening is necessary for neonates who are discharged from NICU.

Evoked Potentials, Auditory, Brain Stem ; Female ; Hearing Loss ; diagnosis ; physiopathology ; Hearing Tests ; Humans ; Infant, Newborn ; Intensive Care Units, Neonatal ; Male ; Risk Factors