BACKGROUND: Computer-assisted orthopaedic surgery (CAOS) improves accuracy and reduces outliers in total knee arthroplasty (TKA). However, during the evaluation of CAOS systems, the error generated by the guidance system (hardware and software) has been generally overlooked. Limited information is available on the accuracy and precision of specific CAOS systems with regard to intraoperative final resection measurements. The purpose of this study was to assess the accuracy and precision of a next generation CAOS system and investigate the impact of extra-articular deformity on the system-level errors generated during intraoperative resection measurement. METHODS: TKA surgeries were performed on twenty-eight artificial knee inserts with various types of extra-articular deformity (12 neutral, 12 varus, and 4 valgus). Surgical resection parameters (resection depths and alignment angles) were compared between postoperative three-dimensional (3D) scan-based measurements and intraoperative CAOS measurements. Using the 3D scan-based measurements as control, the accuracy (mean error) and precision (associated standard deviation) of the CAOS system were assessed. The impact of extra-articular deformity on the CAOS system measurement errors was also investigated. RESULTS: The pooled mean unsigned errors generated by the CAOS system were equal or less than 0.61 mm and 0.64degrees for resection depths and alignment angles, respectively. No clinically meaningful biases were found in the measurements of resection depths (< 0.5 mm) and alignment angles (< 0.5degrees). Extra-articular deformity did not show significant effect on the measurement errors generated by the CAOS system investigated. CONCLUSIONS: This study presented a set of methodology and workflow to assess the system-level accuracy and precision of CAOS systems. The data demonstrated that the CAOS system investigated can offer accurate and precise intraoperative measurements of TKA resection parameters, regardless of the presence of extra-articular deformity in the knee.
Arthroplasty, Replacement, Knee/*methods ; Reproducibility of Results ; *Surgery, Computer-Assisted

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OBJECTIVE: To study the characteristics of the diagnostic parameters of acute respiratory distress syndrome/multiple organ dysfunction syndrome on plateau (H-ARDS/MODS) and compare the accuracy of the three MODS scoring criteria in predicting the outcome of syndrome. METHODS: Five hundred and forty cases fulfilling the criteria of MODS were divided into four groups according to the altitude of their inhabitation area: control group (on plain, CG, n=113, altitude: <430 m), moderate high altitude group 1 (H1G, n=314, altitude: 1,517 m), moderate high altitude group 2 (H2G, n=78, altitude: 2,261 m to 2,400 m) and high altitude group (HG, n=35, altitude: 2 808 m to 3 400 m). According to the diagnostic criteria of Lushan conference and Marshall (1995) commonly used on plain, and Lanzhou criteria drafted by the authors, three data analyzing models were set up to draw the receiver operating characteristic (ROC) curves, the Yordon Index and the optimum cutoff points of the parameters were calculated and the accuracy of the three respective diagnostic criteria was evaluated in predicting the outcome of ARDS/MODS. Multiple factors affecting the outcome of MODS were analyzed using the method of stepwise forward regress model. RESULTS: Following the increase in altitude, Lanzhou criteria was clearly superior to the other two criteria in the area of ROC, the sensitivity, the specificity, and also for the optimum cutoff points of MODS. Multi-variable regression analysis showed that the impacting factor of Lanzhou criteria was the highest (P<0.05). CONCLUSION: (1)Some parameters of the current diagnostic criteria of ARDS/MODS are not suitable in moderately high or high altitude areas. It is necessary to set up the diagnostic criteria of H-ARDS/MODS. (2)Some clinical characteristics might change in areas 1,500 m altitude or higher. The pathophysiological mechanism might be attributable to peculiar biologic reactions due to hypoxia stress reaction, and it is worth further study.
Altitude ; Multiple Organ Failure/*diagnosis ; Prognosis ; ROC Curve ; Regression Analysis ; Respiratory Distress Syndrome, Adult/*diagnosis ; Severity of Illness Index

OBJECTIVE: To investigate the audiological characteristics in unilateral auditory neuropathy (UAN). METHOD: By the retrospective studies, 11 patients which were diagnosed as UAN and bilateral auditory neuropathy (AN) group and control group were measured. RESULT: By the statistical studies of patients from otology clinic data from January 2001 to September 2006,11 patients (11 ear, 5 left ear and 6 right ear, 3.2%) in 340 AN patients diagnosed as UAN were summarized. Four patient were male and 7 were female in 11 patients (1: 1.75). The average age of 11 patients was 20 years old and the average period of diseases was 3.1 years. All patients complained of unilateral gradual hearing loss, and 6 patients in all UAN patients can't discriminate speech correctly. Four patients complained of tinnitus and none of UAN patients complained of dizziness. The pure tone audiograms of 5 patients in all UAN patients (45.4%) were descending curve and those of 4 patients (36.4%) were ascending curve. Eleven patients mostly showed severity degree or midrange degree (6 ear, 54.5%) sensorineural hearing loss. The average pure tone threshold of UAN was obviously higher than the AN group and the speech hearing of UAN is obviously worse, and ABR of all patients was absent, while uninjured side of UAN was normal. Bilateral ears of UAN patients were evoked distortion products otoacoustic emissions. The amplitude of DP-gram and SNR in UAN group was lower obviously (P < 0.05) than the normal control group at all frequencies (0.5-8.0 kHz) and was lower significantly (P < 0.01) at flat and high-frequency, but was lower obviously (P < 0.01) than the AN group at low-frequency. The contralateral suppression effect of DPOAE amplitude in 4 UAN patients of normal ears was suppressed, and that in injured ears was reduced or disappeared, even 0.5 kHz increased DPOAE amplitude. ENG and VEMP were observed in 5 UAN patients, and 1 patients shows semicircular canal failure and 1 patients shows paralysis unilateral. The VEMP of them showed no response in 1 (2 ear) of 5 and showed response in 4 of 5, but the amplitudes of VEMP were lower in 2 UAN patients. CONCLUSION The UAN patients mostly showed ascending curve and ponderosity degree sensorineural hearing loss. The diagnosis of UAN is different from other common sensorineural deafness. The detection of DPOAE and ABR has great significance in diagnosing the UAN.
Adolescent ; Adult ; Audiometry, Pure-Tone ; Auditory Threshold ; Case-Control Studies ; Child ; Child, Preschool ; Evoked Potentials, Auditory, Brain Stem ; Female ; Hearing Loss, Central ; diagnosis ; physiopathology ; Hearing Loss, Unilateral ; diagnosis ; physiopathology ; Humans ; Male ; Retrospective Studies ; Young Adult

The cochlea of children with congenital sensorineural hearing loss with normal inner ear structure was measured and analyzed by high-resolution temporal bone CT(HRCT) imaging technique,its application value before cochlear implantation was evaluated and the appropriate electrode was selected.We collected temporal bone HRCT images of 120 patients with congenital sensorineural hearing loss,according to gender divided into two groups,including 60 males and 60 females.We used the PACS software to measure the distance A(the largest distance from the round window to the lateral wall) and the distance H(height of the cochlea) and calculate the cochlear duct length. Reproducibility of these data were evaluated and the results between the different groups were compared.Measurement of parameter values between the intraobserver and interobserver showed great reproducibility. In the male children group,the measured values are shown as distance A［(8.55±0.31)mm］,distance H［(4.57±0.28)mm］and the cochlear duct length(CDL)［(27.59±1.23)mm］; and in the female children group, the measured values are shown as distance A［(8.45±0.32)mm］,distance H［(4.42±0.34)mm］and the cochlear duct length(CDL)［(27.20±1.17)mm.The A,H,and CDL of the male cochlea were greater than those of the female, the difference was statistically significant(<0.05).Measuring the distance A and distance H of the cochlea and calculating the cochlear duct length CDL can be used to select a suitable length of electrode or to customize a personalized electrode. This is a simple and effective assessment method before cochlear implantation..

BACKGROUND AND PURPOSE: Non-contrast brain computed tomography (NCCT) remains the most common imaging modality employed to select patients for thrombolytic therapy in acute ischemic stroke. The current study used the Alberta Stroke Program Early CT Score (ASPECTS) to identify early ischemic changes on brain NCCT imaging with the aim to investigate whether a relationship exists between time from symptoms onset to NCCT with the presence of early ischaemic change quantified by ASPECTS. METHODS: We studied 1,329 ischemic stroke patients who had NCCT within 8 hours of stroke onset. Patients were assessed to see if they had any ASPECTS lesion and if the rate of patients with a lesion increased with time using logistic regression. RESULTS: 30% patients had an ASPECTS < 10 within the first 3 hours from symptom onset. Within the first 3 hours, the odds for a CT change (ASPECTS < 10) per minute of time was 1.00 with 95% confidence interval (CI) (0.99 to 1.00) (P=0.266). After 3 hours, there was a significant increase in odds of ASPECTS < 10 with increasing time. The odds of being ASPECTS positive increased 1% (odds ratio=1.01) per 1 minute of time with 95% CI (1.00 to 1.01) (P=0.002). CONCLUSIONS: We have identified that prior to first 3 hours of stroke there was no effect of time on odds of CT ischemic change; after the first 3 hours of stroke the odds increased with increasing time to CT scan. The occurrence of early ischemic change may be a marker of time from stroke onset rather than severity.
Alberta ; Brain ; Humans ; Logistic Models ; Stroke* ; Thrombolytic Therapy ; Tomography, X-Ray Computed

OBJECTIVETo survey the status of diagnosis and treatment of biliary tract cancer in Shanghai.

METHODSA clinical epidemiology investigation was carried out on 658 new cases of biliary duct cancers aged 35-74, that registered between June 1997 and May 2001 in urban Shanghai. Clinical findings were collected in 390 gallbladder cancer, 195 bile duct cancer and 73 ampullary cancer.

RESULTSBiliary tract cancers mainly occurred in elderly patients. Ratio of males to female was 1:2.61 in gallbladder cancer, while bile duct cancer and ampullary cancer were slightly more common in men. Association with gallstones was 68.5%, 43.1% and 22.4% for gallbladder cancer, bile duct cancer and ampullary cancer, respectively. Diagnostic accuracy rate of B-ultrasonography was 63.1% in gallbladder cancer. Incidental gallbladder cancer accounted for 20%, while stage IVA and IVB patients reached up to 43.6%. Misdiagnosis rate was still high in bile duct cancer and ampullary cancer, it was 19.1% and 47.1% respectively. In addition, most patients presented jaundice at diagnosis. 69 cases (18.2%) of gallbladder cancer, 50 cases (25.6%) of bile duct cancer and 54 cases (74%) of ampullary cancer underwent radical resection, the 1-, 3- and 5-year survival rates were 58.5%, 42.8% and 40.7%, 58%, 28.3% and 11.1%, 81.5%, 39.2% and 26.9%, respectively. 79 patients with bile duct cancer underwent palliative drainage, and most cases died within 1 year. Metal endo-prostheses or plastic stents were placed into the biliary tract in 38 patients. The median survival was about 7 months.

CONCLUSIONSIt is difficult to make early diagnosis of biliary tract cancers. Standardization of the operation for gallbladder cancer must be respected. Surgical exploration should be undertaken when a bile duct cancer is suspected and there are no contraindications to surgery. Pancreatoduodenectomy should be recommended for ampullary cancer.

Biliary Tract Neoplasms ; diagnosis ; epidemiology ; mortality ; therapy ; China ; epidemiology ; Data Collection ; Female ; Humans ; Male ; Survival Rate

OBJECTIVETo investigate the relationship between tea consumption, biliary tract cancers and gallstone disease.

METHODSA population-based case-control study was conducted in urban Shanghai from 1 June 1997 to 31 May 2001 involving interviews with 627 new cases of biliary tract cancers (including 368 cases of gallbladder cancer, 191 cases of extrahepatic bile duct cancer and 68 cases of cancer of the ampulla of Vater) aged 35 to 74 years and 959 population controls frequency-matched to cases by gender and age in five-year group. 1037 patients of gallstone disease were selected from the same hospital. All subjects were interviewed in person by trained interviewers by use of a structured questionnaire. Unconditional logistic regression analysis was used to calculate adjusted odds ratio (OR) and 95% confidence interval (CI).

RESULTSCompared with tea non-drinkers, current tea consumption was inversely associated with risk of gallbladder cancer, extrahepatic bile duct cancer and gallstone disease among females with OR of 0.57 (95% CI: 0.34-0.96), 0.53 (95% CI: 0.27-1.03) and 0.71 (95% CI: 0.51-0.99), respectively. OR declined with younger age at initiation of tea drinking and with longer duration of tea consumption (P for trend < 0.05). Among males, the corresponding OR were mostly below one, although not statistically significant.

CONCLUSIONTea consumption may decrease the risk of cancers of the gallbladder and extrahepatic bile duct among females. The protective effect appears to be independent of gallstone disease.

Adult ; Aged ; Bile Ducts, Extrahepatic ; Biliary Tract Neoplasms ; epidemiology ; etiology ; Case-Control Studies ; China ; epidemiology ; Female ; Flavonoids ; pharmacology ; Gallbladder Neoplasms ; epidemiology ; etiology ; Gallstones ; epidemiology ; etiology ; Humans ; Male ; Middle Aged ; Phenols ; pharmacology ; Polyphenols ; Protective Agents ; pharmacology ; Risk Factors ; Tea ; chemistry

Objective To investigate the effect of fish oil on intestinal Paneth cells in mouse with abdominal infection. Methods Fifty C57BL/6J mouse were randomly divided into five groups(n=10 each): control group, sham group, infection group (cecal ligation and puncture,CLP), fish oil group (0.4 g/kg fish oil, intragastric administration every day, FO) and long chain triglyceride group (0.4 g/kg soybean oil, intragastric administration every day, LCT). The mouse were sacrificed and the terminal ileum was collected for lysozyme, cryptdin 4 and secreted phosphatidase A2(sPLA2) analysis at the fourth day after operation. The changes of mouse body weight and intestinal mucosa pathology were observed. Results The body weight, the mRNA levels of lysozyme, cryptdin 4 and sPLA2 and the protein level of lysozyme of Paneth cells in the infection group were reduced compared with the control group (0.78±0.34 vs. 1.83±0.11, 0.99±0.44 vs. 2.02±0.33, 0.92±0.25 vs. 1.50±0.27, 0.31± 0.06 vs. 0.45 ±0.05, all P<0.05), meanwhile the intestinal villi collapse and breakage occurred obviously. Fish oil could up-regulate the mRNA and protein expression of lysozyme (1.23±0.27 vs. 0.78± 0.34 and 0.62±0.23, 0.38±0.07 vs. 0.31± 0.06 and 0.32±0.06, all P<0.05) and alleviate the mucosa injury compared with the infection group and LCT group. Conclusions The function of intestinal Paneth cells is damaged apparently after cecal ligation and puncture. Fish oil can relieve this injury.

Objective To investigate the effect of fish oil on intestinal Paneth cells in mouse with abdominal infection. Methods Fifty C57BL/6J mouse were randomly divided into five groups(n=10 each): control group, sham group, infection group (cecal ligation and puncture,CLP), fish oil group (0.4 g/kg fish oil, intragastric administration every day, FO) and long chain triglyceride group (0.4 g/kg soybean oil, intragastric administration every day, LCT). The mouse were sacrificed and the terminal ileum was collected for lysozyme, cryptdin 4 and secreted phosphatidase A2(sPLA2) analysis at the fourth day after operation. The changes of mouse body weight and intestinal mucosa pathology were observed. Results The body weight, the mRNA levels of lysozyme, cryptdin 4 and sPLA2 and the protein level of lysozyme of Paneth cells in the infection group were reduced compared with the control group (0.78±0.34 vs. 1.83±0.11, 0.99±0.44 vs. 2.02±0.33, 0.92±0.25 vs. 1.50±0.27, 0.31± 0.06 vs. 0.45 ±0.05, all P<0.05), meanwhile the intestinal villi collapse and breakage occurred obviously. Fish oil could up-regulate the mRNA and protein expression of lysozyme (1.23±0.27 vs. 0.78± 0.34 and 0.62±0.23, 0.38±0.07 vs. 0.31± 0.06 and 0.32±0.06, all P<0.05) and alleviate the mucosa injury compared with the infection group and LCT group. Conclusions The function of intestinal Paneth cells is damaged apparently after cecal ligation and puncture. Fish oil can relieve this injury.