[Comparative study of percutaneous transfacet screw and pedicle screw in oblique lumbar interbody fusion for the treatment of single-level lumbar spinal stenosis].

Objective: To conduct a comparative study of radiological and clinical outcomes between percutaneous transfacet screw (TFS) and pedicle screw (BPS) in oblique lateral lumbar interbody fusion (OLIF) for single-level lumbar spinal stenosis. Methods: A retrospective cohort study. Patients who underwent OLIF with TFS or BPS for the treatment of single-level lumbar spinal stenosis at Beijing Jishuitan Hospital from January 2019 to June 2022 were retrospectively analyzed. Radiological parameters and clinical indicators were compared between the two groups. Radiological parameters included preoperative, immediate postoperative (within 5 days), and 1-year postoperative measurements of disc height and segmental lordosis angle, as well as interbody fusion status at 1 year postoperatively. Clinical indicators included operative time, blood loss, length of hospital stay, complications, and Oswestry Disability Index (ODI), visual analogue scale (VAS) scores for back pain, and leg pain before and 1 year after surgery. Results: Four male and 10 female patients with an average age of (61.0±11.2) years underwent OLIF with TFS, while 9 male and 12 female patients underwent OLIF with BPS, with a mean age of (60.9±6.7) years. There was no statistically significant difference in preoperative disc height between the TFS and BPS groups (P>0.05). The immediate postoperative disc height was (12.9±2.1) mm and it was (10.4±1.7) mm at 1-year follow-up in the TFS group; in the BPS group, it was (12.9±2.1) mm immediately postoperatively and (11.9±2.1) mm at 1-year follow-up; there was statistically significant difference between the two groups at 1-year follow-up (P=0.037). The segmental lordosis angle showed no significant differences within each group or between the two groups at preoperative, immediate postoperative, or 1-year postoperative follow-up (all P>0.05). At 1-year postoperative follow-up, the fusion rates was 92.9%(13/14) in the TFS group and 95.2%(20/21) in the BPS group, with no statistically significant difference between the two groups (P>0.05). The TFS group had a significantly shorter operative time and less blood loss compared to the BPS group [(164.3±33.9) minutes vs (191.7±31.8) minutes and (74.3±46.9) ml vs (124.8±54.0) ml, respectively] (both P<0.05). Both groups showed significant improvement in ODI and VAS scores at 1 year postoperatively compared to those preoperatively, but with no statistically significant difference was found between the groups (both P>0.05). Conclusions: OLIF with TFS fixation can effectively restore disc height and alleviate back and leg pain in patients with single-level lumbar spinal stenosis. Compared to the OLIF with BPS procedure, OLIF with TFS has shorter operative time and less blood loss.

The investigation of post-thaw chilled storage and the applicability of large-scale cryopreservation in chub (Squalius cephalus) sperm.

Chub (reophillic cyprinids) is one of the most sensitive bioindicator fish of environmental changes following anthropogenic activities. The improvement of different biotechnological procedures could help support its conservation and strengthen the natural populations. The aim of this study was to compare the effects of two different hormonal agents (carp pituitary extract and Ovopel™) on various motility parameters (pMOT-%, DAP-µm, VCL µm s-1, VSL-µm s-1, LIN-%, ALH-µm, BCF-Hz) of fresh and cryopreserved/thawed sperm (stored at 4 °C for 6 h). Additionally, we sought to develop a novel, large-scale cryopreservation method for chub sperm, assessing freezing methods (Styrofoam box and a controlled-rate freezer) and different containers (0.5, 5 mL straw and 4 mL cryotube) for sperm cryopreservation. The results of this study indicated no difference between the carp pituitary extract and Ovopel treated groups in either the fresh or frozen/thawed sperm (at 0, 3, 6, hour post thawing, P = 0.4351). In contrast, the quality of the thawed chub sperm was negatively affected after 3 h chilled storage in both hormonal treatments (P = 0.0036, P < 0.0001). When assessing the motility parameters of the sperm between the 5 mL straw and 4 mL cryotube groups cryopreserved in a Styrofoam Box, no difference was observed (P = 0.103). Additionally, sperm loaded in 4 mL cryotubes showed no difference in motility when cryopreserved with either the Styrofoam box or controlled-rate freezer methods (P = 0.109). A similar hatching rate was observed in sperm preserved using the Styrofoam box (35 ± 7 %) and controlled rate freezer (25 ± 9 %) methods (P = 0.300). In a second fertilization trial, hatching rate was similar between control (72 ± 19 %) and cryopreserved (4 mL cryotube and Styrofoam box, 61 ± 5 %) groups. (P = 0.257). Based on our findings and its standard features (less species specific, precise dose calculation), Ovopel can be a good candidate for the stimulation of spermiation in chub sperm prior to cryopreservation. Furthermore, our study presents a novel and applicable method for the large-scale cryopreservation of chub sperm.

[The value of immunohistochemical expression of Ki-67 and CD34 in differentiating ductal carcinoma in situ from ductal carcinoma in situ-like invasive breast cancer].

Objective: To investigate the expression of Ki-67 and CD34 in the differential diagnosis of ductal carcinoma in situ (DCIS) and DCIS-like invasive breast cancer (DLIBC). Methods: A total of 100 cases of DCIS and 150 cases of DLIBC diagnosed pathologically in Yantai Yuhuangding Hospital from January 2019 to March 2022 were collected. The expression of p63, CK5/6, Ki-67 and CD34 in both groups were detected by immunohistochemical (IHC) staining and evaluated. Results: The 100 cases of DCIS included 11 cases of low-grade DCIS, 28 cases of intermediate-grade DCIS and 61 cases of high-grade DCIS. IHC staining of p63 and CK5/6 showed the myoepithelial cells around cancerous duct were complete or partial absence. Ki-67 expression showed two patterns: high expression in the basal layers and scattered expression within the tumor. Most cases showed mainly high basal expression (77/100, 77%), and the proportion of this pattern was significantly different between low grade and high grade DCIS (P<0.05). All cases showed complete CD34 expression surrounding the cancerous duct with different proportion (vascular necklace) suggested small vessels proliferation. The 150 cases of DLIBC included 142 cases of invasive ductal carcinoma (IDC) (three cases of basal-like breast cancer was included), two cases of secretory carcinoma, three cases of solid papillary carcinoma, two cases of adenoid cystic carcinoma and one case of acinar cell carcinoma. Among 142 cases of IDC, 13 cases were grade Ⅰ, 77 were grade Ⅱ and 52 were grade Ⅲ. IHC staining of p63 showed complete absence of myoepithelium. CK5/6 was negative in most cases and only positively expressed within the tumor in 3 cases of basal-like breast cancer. Ki-67 indicated a scattered expression pattern within the tumor. In most cases, CD34 immunostaining showed scattered positive blood vessels within the tumor while only two cases showed incomplete expression of CD34 around the tumor (2/150, 1.3%). The different expression patterns of Ki-67 and CD34 in DCIS and DLIBC was statistically significant (P<0.05). Conclusions: The different expression patterns of Ki-67 and CD34 are helpful to distinguish DLIBC from DCIS. The appearance of "vascular necklace" with CD34 and the high expression of Ki-67 around the cancerous duct highly support the diagnosis of DCIS, and the scattered expression pattern of CD34 supports DLIBC.

[Study on parameters of robot-assisted ultrasonic drilling on bovine vertebral body].

Objective: To investigate the effect of ultrasonic parameter settings on maximum temperatures in the drilling site and penetration time and determine the most suitable parameters for efficient and safe robot-based ultrasonic bone drilling in spinal surgery. Methods: Five adult bovine thoracic and lumbar vertebrae specimens (T10-L6) were cut into 10 mm thick slices. A total of 50 slices were obtained. Among them, 30 and 20 slices were used for cancellous bone experiments and cortical bone experiments, respectively. In the cancellous bone experiment, the slices were randomly divided into three groups, corresponding to different feed rates of 0.8 mm/s, 1.6 mm/s, and 2.4 mm/s, respectively, with 10 slices in each group. The cancellous part of each slice was drilled 9 times with different output powers from 20% (48 W) to 100% (120 W). In the cortical bone experiment, the slices were randomly assigned into two groups, corresponding to a different feed rate (0.8 mm/s and 1.6 mm/s). Drilling was performed on the cortical part of each slice 4 times with different output power, which increased from 70% (84W) to 100% (120 W). All experiments were conducted at room temperature of 25 ℃. Maximum temperature and penetration time were recorded. The maximum grinding temperature and penetration time of cancellous bone and cortical bone under different output power and feed rate were compared. Results: At the same feed rate, the maximum temperature of the cancellous bone decreased as output power increased. There were statistically significant differences in the maximum temperature between the output powers of 120 W and 24 W under different feed rates(61.2 ℃±9.4 ℃ vs 70.9 ℃±5.7 ℃, 59.2 ℃±7.1 ℃ vs 69.5 ℃±10.7 ℃, 55.5 ℃±5.5 ℃ vs 69.2 ℃±9.3 ℃, all P<0.05). At the premise of the same output power, there was no significant difference in the maximum temperature among different feed rates (all P>0.05). At the feed rate of 0.8 mm/s, the maximum temperature of cortical bone decreased as the output power increased. The maximum temperature at the output power of 120 W was significantly lower than that of 84 W (P=0.048). However, at the feed rate of 1.6 mm/s, the maximum temperature could not be significantly lowered by the increase in output power (P>0.05). Under the same output power, the maximum temperature at the feed rate of 1.6 mm/s were all significantly lower than those of 0.8 mm/s (all P<0.05). The penetration time of cancellous bone did not decrease significantly with the increase in the output power (all P>0.05) while it decreased significantly as the feed rate increased (all P<0.05). Regarding cortical bone at the feed rate of 0.8 mm/s, the increase in output power could not shorten the penetration time (P>0.05); at the feed rate of 1.6 mm/s, the penetration time at the output power of 120 W was significantly shorter than that of 96 W (P=0.008). With the same output power, the penetration time at the feed rate of 1.6 mm/s were significantly shorter than those at 0.8 mm/s (all P<0.05). There was no statistical difference in the penetration failure rate among different feed rates with the same output power (all P>0.05). The penetration failure rate was 0 when the output power of cancellous bone was 48 W and above and the output power of cortical bone were 108 W and 120 W. Conclusions: The maximum temperature of vertebral cancellous bone and the cortical bone is primarily influenced by the output power and the feed rate, respectively; the penetration time of cancellous bone and the cortical bone is affected by the feed rate and both of feed rate and output power, respectively. The most suitable parameters are output power of 120 W and feed rate of 2.4 mm/s for cancellous bone and output power of 120 W and feed rate of 1.6 mm/s for cortical bone.

Choice between video-assisted thoracic surgery and thoracotomy: importance of required operative time and blood transfusion.

OBJECTIVE: The current evidence in support of Video-assisted thoracic surgery (VATS) over conventional open thoracotomy is based upon outcomes related to perioperative complications. The aim of the current study was to compare the mean operative time and amount of blood transfusion required for VATS and thoracotomy. PATIENTS AND METHODS: A retrospective data analysis was carried out of all patients undergoing pulmonary surgery in the year 2017 for either for benign or malignant conditions at our institute. The primary outcomes were mean operative times and amounts of blood transfusion required during the procedure. Adjusted regression models were used to draw an association between the type of surgical modality (VATS or thoracotomy) and the outcomes considered. RESULTS: There were 278 subjects that underwent VATS and 237 that had thoracotomy. The mean operating time for the VATS group (2.58 ± 0.98 hours) was significantly less than that of the thoracotomy group (2.99 ± 1.18 hours). Similarly, the amounts of combined blood and plasma transfused were significantly less with VATS (5.81±6.3 units) as compared to the thoracotomy group (9.9 ± 15.1 units). VATS also required significantly fewer blood units as compared to thoracotomy (3.79 ± 3.1 vs. 7.15 ± 12.3). Our analysis indicated that, with VATS, the requirement of blood and plasma transfusion was reduced by nearly 4 units (b=-4.09; 95% CI: -6.04, -2.14) and the mean operative time was reduced by around 40 minutes (b=-0.41; 95% CI: -0.60, -0.22). CONCLUSIONS: Both VATS and thoracotomy are acceptable surgical techniques for the management of lung pathology. However, VATS technique is associated with lower need for blood transfusion and reduced operating time. The decision of the surgical technique should be guided by the availability of resources and the skills of the surgeon.

The systematic development and optimization of large-scale sperm cryopreservation in northern pike (Esox lucius).

In our study, a systematic development of a new large-scale sperm cryopreservation protocol was carried out in northern pike (Esox lucius). The effect of 2 sugar based (glucose and trehalose) extenders, 3 dilution ratios (1:3, 1:9 and 1:19) 2 vol straws (0.5 and 5 mL) and a 10 mL cryotube, 2 different cryopreservation methods (Polystyrene box-P. box and Controlled Rate Freezer-CRF), as well as 3 different thawing periods (3, 3.5 and 4 min) were investigated on the motility of thawed sperm. The glucose based extender showed significantly higher pMOT (1:3-18 ± 16%, 1:9-20 ± 13%, 1:19-16 ± 12%) at all dilution ratios than in the trehalose based extender (1:3-0.3 ± 1%, 1:9-1±1%, 1:19-4±2%). A similar tendency was recorded in VCL and STR at a ratio 1:3 and 1:9. No significant difference was measured in sperm movement between the P. box and CRF using the 0.5 mL straw. Similarly no significant difference was observed in all motility parameters with 10 mL cryotube frozen in CRF at a ratio 1:3-1:19. An effective and short thawing period (3 min) was experimentally specified for the 10 mL cryotube cryopreserved in the CRF. In all large-scale cryopreservation methods, high pMOT (straw CRF: 57 ± 10%, straw P. box: 50 ± 9%, cryotube CRF: 41 ± 10%), and STR were measured, and no significant difference was recorded in all motility parameters. Our results demonstrate the effectiveness of our newly developed extender and the applicability of 3 different large-scale cryopreservation methods in pike sperm. Our protocols could be new prospective candidates for future exploitation in hatchery practice.

Histopathologic analysis of stage pT1b kidney neoplasms for optimal surgical margins of nephron-sparing surgery.

OBJECTIVE: To evaluate the pathological features and define the optimal surgical margins (SM) of nephron-sparing surgery (NSS) for kidney neoplasms 4-7 cm (stage pT1b) on preoperative imaging. MATERIALS AND METHODS: The retrospective study included 748 patients who were diagnosed stage pT1b renal tumors and underwent either radical nephrectomy (RN, n = 475) or NSS (n = 273) from January 2004 to March 2017. The tumor size, pathological subtype, Fuhrman grade, status of peritumoral pseudocapsule (PC) and tumor multifocality were recorded. The relationship between peritumoral PC and positive SM was calculated statistically by Fisher's exact probability test. RESULTS: The mean tumor diameter was 5.4 cm (range: 4.1-7.0 cm), 65 (8.7%) cases were discovered with multifocal lesions and 686 (91.7%) were surrounded with peritumoral PC in all 748 specimens. 57 (8.3%) of 686 cases were proved with tumor infiltrated beyond PC [infiltration (+)], and the presence of PC infiltration (+) was significantly correlated with positive SM (p = 0.016). The infiltrative depth of tumor cells into renal parenchyma beyond PC was all limited in 3 mm and the proportion of ≤ 1, 1-2 and 2-3 mm was 21.1% (12/57), 59.6% (34/57) and 19.3% (11/57), respectively. CONCLUSIONS: Our report indicates a 3 mm excisional margin is acceptable to ensure negative SM when operating NSS on stage pT1b kidney neoplasms.

The identification of multifocal breast cancer-associated long non-coding RNAs.

OBJECTIVE: To identify long non-coding RNAs (lncRNAs), which may be associated with multifocal and multicentric breast cancer (MMBC) by analyzing the differential expression of non-coding RNA in MMBC and unifocal breast cancers (UBC). PATIENTS AND METHODS: 156 cases of invasive MMBC patients (136 patients with 2 focuses and 20 patients with 3 focuses) and 130 cases of UBC were collected from January 2005 to December 2015 in Yantai Yuhuangding Hospital. The differentially expressed lncRNAs in MMBC and UBC were screened by gene chip. RT-PCR was used to verify the differentially expressed lncRNAs. RESULTS: Significantly different expression was found in 1080 lncRNAs between MMBC and UBC (FC > 4, p < 0.05), among which, 458 were upregulated and 622 were down-regulated. In homologous lncRNAs, the expression levels of four lncRNAs including C19orf33, C3orf52, C15orf48 and C4orf19 in MMBC tissue were significantly different than those in UBC tissues. RT-PCR verified that the expression of C19orf33, C3orf52 and C15orf48 in MMBC tissue was significantly up-regulated and the expression of C4orf19 was significantly down-regulated, which was consistent with that of gene chip. CONCLUSIONS: C19orf33, C3orf52, C15orf48 and C4orf19 may have important functions in MMBC, and may be used as markers for MMBC.

Exact inference for the risk ratio with an imperfect diagnostic test.

The risk ratio quantifies the risk of disease in a study population relative to a reference population. Standard methods of estimation and testing assume a perfect diagnostic test having sensitivity and specificity of 100%. However, this assumption typically does not hold, and this may invalidate naive estimation and testing for the risk ratio. We propose procedures that control for sensitivity and specificity of the diagnostic test, given the risks are measured by proportions, as it is in cross-sectional studies or studies with fixed follow-up times. These procedures provide an exact unconditional test and confidence interval for the true risk ratio. The methods also cover the case when sensitivity and specificity differ in the two groups (differential misclassification). The resulting test and confidence interval may be useful in epidemiological studies as well as in clinical and vaccine trials. We illustrate the method with real-life examples which demonstrate that ignoring sensitivity and specificity of the diagnostic test may lead to considerable bias in the estimated risk ratio.

Novel pH sensing semiconductor for point-of-care detection of HIV-1 viremia.

The timely detection of viremia in HIV-infected patients receiving antiviral treatment is key to ensuring effective therapy and preventing the emergence of drug resistance. In high HIV burden settings, the cost and complexity of diagnostics limit their availability. We have developed a novel complementary metal-oxide semiconductor (CMOS) chip based, pH-mediated, point-of-care HIV-1 viral load monitoring assay that simultaneously amplifies and detects HIV-1 RNA. A novel low-buffer HIV-1 pH-LAMP (loop-mediated isothermal amplification) assay was optimised and incorporated into a pH sensitive CMOS chip. Screening of 991 clinical samples (164 on the chip) yielded a sensitivity of 95% (in vitro) and 88.8% (on-chip) at >1000 RNA copies/reaction across a broad spectrum of HIV-1 viral clades. Median time to detection was 20.8 minutes in samples with >1000 copies RNA. The sensitivity, specificity and reproducibility are close to that required to produce a point-of-care device which would be of benefit in resource poor regions, and could be performed on an USB stick or similar low power device.

A randomised, phase II study of intetumumab, an anti-αv-integrin mAb, alone and with dacarbazine in stage IV melanoma.

BACKGROUND: α(v) integrins are involved in angiogenesis and melanoma tumourigenesis. Intetumumab (CNTO 95) is a fully human anti-α(v)-integrin monoclonal antibody. METHODS: In a multicentre, randomised, phase II study, stage IV melanoma patients were randomised 1:1:1:1 to 1000 mg m(-2) dacarbazine+placebo (n=32), 1000 mg m(-2) dacarbazine+10 mg kg(-1) intetumumab (n=32), 10 mg kg(-1) intetumumab (n=33), or 5 mg kg(-1) intetumumab (n=32) q3w. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), adverse events, and pharmacokinetics. RESULTS: No statistically significant differences in efficacy were observed between groups. In the dacarbazine+placebo, dacarbazine+intetumumab, 10 mg kg(-1) intetumumab, and 5 mg kg(-1) intetumumab groups, median PFS was 1.8, 2.5, 1.4, and 1.4 months; median OS was 8, 11, 15, and 9.8 months; and ORR of complete+partial response was 10, 3, 6, and 0%. Nonlinear intetumumab pharmacokinetics and potential intetumumab-dacarbazine interactions were observed. Transient, asymptomatic, nonrecurring, grade 1-2, uveitic reactions that resolved spontaneously or with topical steroids were seen in 22-30% of intetumumab-treated patients. Low-grade infusion-reaction symptoms (headache, fatigue, nausea, vomiting, fever, chills) were observed, as expected, in 16-73% of dacarbazine-treated patients. No intetumumab-related myelosuppression, laboratory/electrocardiogram abnormalities, or deaths occurred. CONCLUSION: With its favourable safety profile and a nonsignificant trend towards improved OS, intetumumab merits further investigation in advanced melanoma.

Clinical correlates of white matter blood flow perfusion changes in Sturge-Weber syndrome: a dynamic MR perfusion-weighted imaging study.

BACKGROUND AND PURPOSE: Low brain tissue perfusion due to abnormal venous drainage is thought to be a central mechanism of brain damage in SWS. Here, HR-PWI was used to quantify WM perfusion abnormalities and to correlate these with brain atrophy and clinical variables. MATERIALS AND METHODS: Fourteen children (age range, 0.8-10.0 years) with unilateral SWS underwent MR imaging examinations, including HR-PWI. rCBV, rCBF, and MTT in the affected WM and in contralateral homotopic WM were measured. AI for each perfusion parameter was correlated with age, brain atrophy, and motor and seizure variables as well as IQ. RESULTS: Increased perfusion was seen in the affected hemisphere in 5 children and decreased perfusion in 9 children. Brain atrophy was more severe in the low-perfusion group (P = .01) and was related to both CBF-AI and CBV-AI (r = -0.69, P = .007; r = -0.64, P = .014, respectively). Older children had lower CBV values on the affected side (r = -0.62, P = .02). Longer duration of epilepsy was related to lower CBF (more negative CBF-AI, r = -0.58, P = .03) and low CBV (r = -0.55, P = .04) on the affected side. Lower perfusion was associated with more frequent seizures (rCBF-AI: r = -0.56, P = .04; rCBV-AI: r = -0.63, P = .02). CONCLUSIONS: Increased perfusion in the affected cerebral WM may indicate an early stage of SWS without severe brain atrophy. Decreased perfusion is associated with frequent seizures, long duration of epilepsy, and brain atrophy.

Accuracy of noninvasive quantification of brain NAA concentrations using PRESS sequence: verification in a swine model with external standard.

The metabolite ratios had been employed in the field of MR spectroscopy (MRS) for a long period. The main drawback of metabolite ratio is that ratio results are not comparable with absolute metabolite concentration in vivo. The purpose of this study was to examine the accuracy of noninvasive quantification of brain N-acetylaspartate (NAA) concentrations using previously reported MR external standard method. Eight swine were scanned on a GE 1.5 T scanner with a standard head coil. The external standard method was utilized with a sphere filled with NAA, GABA, glutamine, glutamate, creatine, choline chloride, and myo-inositol. The position resolved spectroscopy (PRESS) sequence was used with TE=135 msec, TR=1500 msec, and 128 scan averages. The analysis of MRS was done with SAGE/IDL program. In vivo NAA concentration was obtained using the equation S=N * e(-TE/T2) * [1-e(-TR/T1). In vitro NAA concentration was measured by high performance liquid chromatography (HPLC). In the MRS group, the mean concentration of NAA was 10.03 plusmn 0.74 mmol/kg. In the HPLC group, the mean concentration of NAA was 9.22 plusmn 0.55 mmol/kg. There was no significant difference between the two groups (p = 0.46). However, slightly higher value was observed in the MRS group (7/8 swine), compared with HPLC group. The range of differences was between 0.02~2.05 mmol/kg. MRS external reference method could be more accurate than internal reference method. 1H MRS does not distinguish between N-acetyl resonance frequencies and other N-acetylated amino acids.

Chromosomal transformation in donor cells following allogeneic bone marrow transplantation.

We report here a monosomy 7 transformation of donor cells following matched-unrelated, same sex, allogeneic bone marrow transplantation in a patient with severe congenital aplastic anemia. A PCR technique was employed to amplify microsatellite markers on chromosome 7 to confirm donor/recipient identity. We found that the transformation of monosomy 7 occurred in previously genetically normal donor cells. This study suggests that the microenvironment of the bone marrow of our patient with severe congenital aplastic anemia may have played a critical role in the development of monosomy 7 of normal donor cells and we conclude that chromosomal microsatellite marker analysis can be a valuable tool for precise donor/recipient differentiation in engraftment monitoring.

Improving spatial signal homogeneity in MR 2D chemical shift imaging using outer volume saturation bands.

Many endeavors of improving chemical shift imaging (CSI) techniques have been made during last two decades. Good examples of two-dimensional CSI and three-dimensional CSI can be found in the literature. However, clinical CSI using available sequences is still not satisfactory. The purpose of this study was to assess the effect of outer volume saturation bands on signal homogeneity in MR 2D chemical shift imaging. The 2D CSI scans were acquired using a point resolved spectroscopy (PRESS) CSI sequence on a phantom filled with brain metabolites. A single PRESS volume of interest was prescribed graphically. The acquisition matrix was 18x18 phase encodings over a 24-cm FOV. Identical acquisitions were obtained with and without outer-volume saturation bands. After initial acquisition was obtained, four more acquisitions were repeated for both studies with and without saturation bands. Identical five groups of voxels were compared for both studies. Standard deviations of metabolite ratios were calculated in each group for both studies. Spectra obtained without outer-volume saturation bands showed signal to noise gradient with higher concentration of signal within voxels at the center of the volume of interest. Outer volume saturation bands reduced this gradient. In general, standard deviations of metabolite ratios with saturation bands were smaller than those without saturation bands. Improved spatial homogeneity of spectra in voxels of CSI with saturation bands was obtained. Outer-volume saturation bands improve spatial signal homogeneity of chemical shift imaging.

[A comparative study on clinical and pathological diagnosis in patients with chronic viral hepatitis].

OBJECTIVE: To provide some suggestions for revision of "1995's program on prevention and treatment of viral hepatitis", a study on the correlation between clinical and pathological diagnosis of chronic hepatitis was performed. METHODS: The main clinical symptoms, signs, and laboratory data taken from 664 patients with mild, moderate and severe chronic viral hepatitis were analyzed and compared with their corresponding pathological findings. RESULTS: The incidence of symptoms such as fatigue, poor appetite, nausea and flatulence was 51.5% to 91.2% in the order of the severity of hepatopathological damage. Splenomegaly and spider nevus showed a close correlation with the degree of pathological changes, especially with the former the incidence being 25.4%, 35.8% and 41.1% among the mild, moderate and severe groups respectively (P < 0.01). In addition to ALT and other five laboratory parameters listed in the program, a remarkable difference of AST and platelet count was also shown in the three groups. There was a better correlation between laboratory results and pathological findings in mild chronic hepatitis, and each one might attain from 65.4% to 93.6%, but this was not so in moderate except for A/G(53.2%) and in severe except for ALT(30.2%) according to the "1995's program on prevention and treatment of viral hepatitis". CONCLUSIONS: A comprehensive judgment for the diagnosis of chronic viral hepatitis should combine clinical symptoms, signs and laboratory results. Great attention should be paid to the significance of clinical symptoms and splenomegaly. AST and platelet count might be included as diagnostic parameters in the new revised program on prevention and treatment of viral hepatitis.