Single-portal-phase low-tube-voltage dual-energy CT for short-term follow-up of acute pancreatitis: evaluation of CT severity index,interobserver agreement and radiation dose

Objectives

To intra-individually compare single-portal-phase low-tube-voltage (100-kVp) computed tomography (CT) with 120-kVp images for short-term follow-up assessment of CT severity index (CTSI) of acute pancreatitis, interobserver agreement and radiation dose.

Methods

We retrospectively analysed 66 patients with acute pancreatitis who underwent initial dual-contrast-phase CT (unenhanced, arterial, portal phase) at admission and short-term (mean interval 11.4 days) follow-up dual-contrast-phase dual-energy CT. The 100-kVp and linearly blended images representing 120-kVp acquisition follow-up CT images were independently evaluated by three radiologists using a modified CTSI assessing pancreatic inflammation, necrosis and extrapancreatic complications. Scores were compared with paired t test and interobserver agreement was evaluated using intraclass correlation coefficients (ICC).

Results

Mean CTSI scores on unenhanced, portal- and dual-contrast-phase images were 4.9, 6.1 and 6.2 (120 kVp) and 5.0, 6.0 and 6.1 (100 kVp), respectively. Contrast-enhanced series showed a higher CTSI compared to unenhanced images (P?P?>?0.7). CTSI scores were comparable for 100-kVp and 120-kVp images (P?>?0.05). Interobserver agreement was substantial for all evaluated series and subcategories (ICC 0.67–0.93). DLP of single-portal-phase 100-kVp images was reduced by 41 % compared to 120-kVp images (363.8 versus 615.9 mGy cm).

Conclusions

Low-tube-voltage single-phase 100-kVp CT provides sufficient information for follow-up evaluation of acute pancreatitis and significantly reduces radiation exposure.

Key Points

? Single-portal-phase CT provides sufficient evaluation for follow-up of acute pancreatitis. ? Follow-up CT does not benefit from unenhanced or arterial-phase acquisition. ? CT severity index scores are equal for dual-contrast-phase 100-/120-kVp acquisition (P?>?0.05). ? 100-kVp single-portal-phase follow-up CT of acute pancreatitis significantly reduces radiation exposure.     

Multiple arterial revascularization using the tangential K-graft technique

The tangential K graft is a comfortable surgical technique aiming to increase cardiac surgeons' versatility in performing multiple arterial grafting using only two arterial conduits. One end of the free graft--either the right internal thoracic artery (RITA) or the radial artery (RA)--is attached to a marginal circumflex branch. Its other end is anastomosed end to side to a diagonal branch. After the left internal thoracic artery (LITA) is attached to the left anterior descending coronary artery, a wide-open side-to-side LITA to free RITA or RA anastomosis--resembling the letter K--is constructed.     

Value of Laparoscopic Appendectomy in the Elderly Patient

Background  Acute appendicitis (AA) in elderly patients (60 years of age and older) is a challenging problem associated with significant morbidity and mortality when perforation is present. We hypothesized that laparoscopic appendectomy (LA) would enable an earlier correct diagnosis and have advantages in elderly patients. Methods  We performed a retrospective review of patients who underwent laparoscopic appendectomy for suspected AA. Data of elderly patients were compared to data of younger patients (18 to <60 years of age). Results  Fifty-four LA were performed in elderly patients and 423 in younger patients. Patients over the age of 60 years had more co-morbidities and required more frequent use of anticoagulants. Preoperative imaging (ultrasound or computerized tomography) was significantly more frequent in elderly patients (36% versus 15%), and was associated with a higher rate of confirmation of acute appendicitis (78% versus 55%), which allowed a decrease in the rate of negative surgical explorations to 4.1% in elderly patients compared to 10.2% in younger patients. Complicated appendicitis and conversions were more frequent in the elderly patients. This resulted in prolonged operative time and longer hospital stay for this group. The overall complication rate was equivalent in the two groups, without differences in the occurrence either of infectious complications or of complications related to surgical site. There were no deaths following appendectomy in our series. Conclusions  Laparoscopic appendectomy is safe in the elderly population and is not associated with any increase in morbidity. The high incidence of complicated appendicitis in elderly patients affects operative time and length of hospital stay following laparoscopic appendectomy, and it can also lead to an increased rate of conversion to an open procedure. Use of preoperative abdominal computerized tomography scan is mandatory in elderly patients to provide an early diagnosis and to decrease unnecessary surgical exploration when acute appendicitis is suspected.     

Dose and image quality of high-pitch dual source computed tomography for the evaluation of cervical lymph node status – Comparison to regular 128-slice single source computed tomography

Purpose

A high-pitch dual-source CT (DSCT) was compared to a standard single-source CT protocol in terms of dose and image quality for malignant lymphoma staging.

Materials and methods

Data from 43 patients who underwent DSCT (group 1) of the neck for staging of malignant lymphoma and 40 patients who underwent regular single source CT (group 2) were investigated retrospectively. Volume CT dose index (CTDIvol), dose length product (DLP), background noise (BN), attenuation values, signal-to-noise-ratio (SNR), scan time, effective tube current-time product (eff. mAs), subjective diagnostic image quality and artifact burden were compared.

Results

CTDIvol (5.5 ± 0.8 mGy vs. 12.4 ± 1.4 mGy), DLP (172 ± 27 mGycm vs. 344 ± 60 mGycm, p < 0.0001), eff. mAs (98 ± 15 mAs vs. 183 ± 20 mAs, p < 0.0001) and scan time (0.64 ± 0.05 s vs. 8.21 ± 0.72 s) were lower for group 1. BN was higher (p < 0.001) for group 1 with a mean difference of 2.6 HU. SNR for sternocleidomastoid and pectoral muscle was lower (6.6–12.3 vs. 7.8–19.1) for group 1. Subjective image quality (1.55 ± 0.6 vs. 1.42 ± 0.5) and artifact burden (1.62 ± 1.0 vs. 1.57 ± 0.9) were not rated significantly different (p = 0.47 and p = 0.80) with a good inter-observer agreement (κ = 0.59–0.90).

Conclusion

High-pitch DSCT allows reduction of patient dose for cervical lymphoma staging while diagnostic image quality is preserved.     

Contrast-enhanced T1-weighted fluid-attenuated inversion-recovery BLADE magnetic resonance imaging of the brain: an alternative to spin-echo technique for detection of brain lesions in the unsedated pediatric patient?

RATIONALE AND OBJECTIVES: We compared contrast-enhanced T1-weighted magnetic resonance (MR) imaging of the brain using different types of data acquisition techniques: periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER, BLADE) imaging versus standard k-space sampling (conventional spin-echo pulse sequence) in the unsedated pediatric patient with focus on artifact reduction, overall image quality, and lesion detectability. MATERIALS AND METHODS: Forty-eight pediatric patients (aged 3 months to 18 years) were scanned with a clinical 1.5-T whole body MR scanner. Cross-sectional contrast-enhanced T1-weighted spin-echo sequence was compared to a T1-weighted dark-fluid fluid-attenuated inversion-recovery (FLAIR) BLADE sequence for qualitative and quantitative criteria (image artifacts, image quality, lesion detectability) by two experienced radiologists. Imaging protocols were matched for imaging parameters. Reader agreement was assessed using the exact Bowker test. RESULTS: BLADE images showed significantly less pulsation and motion artifacts than the standard T1-weighted spin-echo sequence scan. BLADE images showed statistically significant lower signal-to-noise ratio but higher contrast-to-noise ratios with superior gray-white matter contrast. All lesions were demonstrated on FLAIR BLADE imaging, and one false-positive lesion was visible in spin-echo sequence images. CONCLUSION: BLADE MR imaging at 1.5 T is applicable for central nervous system imaging of the unsedated pediatric patient, reduces motion and pulsation artifacts, and minimizes the need for sedation or general anesthesia without loss of relevant diagnostic information.     

Is primary endoscopic puncture of ureterocele a long-term effective procedure?

Background/Purpose: For more than a decade, endoscopic puncture of ureterocele has been recommended as an initial and, in the majority of the patients, as a definitive procedure. This study evaluates the long-term effectiveness of primary endoscopic puncture of ureterocele. Methods: Over the last 18 years (1984 through 2001), 52 patients (median age 3 months) underwent primary endoscopic puncture of ureterocele. The median follow-up was 9 years (6 months to 18 years). Antenatal ultrasound scan detected hydronephrosis and led to the postnatal diagnosis of ureterocele in 12 (23%) children, whereas in the remaining 40 (77%) children the diagnosis was made on investigation for urinary tract infection (UTI). The ureterocele presented as a part of renal duplication in 48 (92%) patients and a single system in 4 (8%). Forty-four (92%) of the patients with duplication presented with non- or poorly functioning upper poles. Vesicoureteric reflux (VUR) was seen in the lower moiety of the ipsilateral kidney in 31 and in 18 of the contralateral kidney comprising 49 renal refluxing units (RRU). Results: Complete decompression of the ureterocele was achieved in 48 (92%) patients after the first endoscopic puncture. Four (8%) patients required a second puncture of ureterocele. Nine (17%) of the 52 patients underwent nephrectomy for a nonfunctioning kidney. Ten (19%) patients required upper pole partial nephrectomy owing to nonfunctioning upper pole. Twenty-nine (59%) of the 49 RRU showed spontaneous resolution of VUR. Sixteen (33%) RRU underwent endoscopic correction of VUR. One required ureteric reimplantation. The remaining 4 (8%) are maintained on prophylactic antibiotics. Five (10%) patients had VUR in the upper pole moieties after ureterocele puncture. Conclusions: Our data suggest that primary endoscopic puncture of ureteroceles is a simple, long-term, effective, and safe procedure avoiding complete reconstruction in the majority of the patients. J Pediatr Surg 38:116-119.     

Clusterin knockdown using the antisense oligonucleotide OGX-011 re-sensitizes docetaxel-refractory prostate cancer PC-3 cells to chemotherapy

OBJECTIVES

To characterize changes in secretory clusterin (sCLU) expression in prostate cancer cells after treatment with docetaxel and to determine whether sCLU knockdown can re‐introduce chemosensitivity in a docetaxel‐resistant, androgen‐independent human prostate cancer model.

PATIENTS AND METHODS

A tissue microarray was constructed for 84 radical prostatectomy (RP) specimens from a multicentre Phase II trial of neoadjuvant combined androgen ablation and docetaxel (CUOG‐P01a) and assessed for changes in the expression of the cytoprotective chaperone sCLU. The human prostate cancer cell line PC‐3 was repeatedly exposed to docetaxel chemotherapy in vitro, and a docetaxel‐resistant cell subline (PC‐3dR) was developed and analysed.

RESULTS

sCLU levels were significantly higher in RP specimens treated with neoadjuvant combined androgen ablation and docetaxel than in untreated specimens. Similarly, sCLU expression increased 2.5‐fold in the newly developed docetaxel‐refractory PC‐3dR cell line compared with parental PC‐3 cells. There was a dose‐dependent and sequence‐specific decrease in sCLU levels in PC‐3dR cells using OGX‐011, an antisense oligonucleotide against human sCLU. OGX‐011 and small‐interference RNA both chemosensitized PC‐3dR cells to docetaxel and mitoxantrone in vitro and apoptotic rates in PC‐3dR cells were significantly increased when OGX‐011 was combined with docetaxel. In vivo, growth of PC‐3dR xenografts in nude mice was synergistically inhibited by OGX‐011 combined with paclitaxel or mitoxantrone (by 76% and 44% compared with their mismatch controls, respectively).

CONCLUSION

The present findings indicate that targeted knockdown of sCLU enhances the effects of cytotoxic chemotherapy in docetaxel‐refractory cells, and provide preclinical proof of principle for clinical trials testing OGX‐011 in second‐line chemotherapy regimens for patients with docetaxel‐refractory prostate cancer.     

Ureterosciatic hernia: a rare cause of ureteral obstruction visualized by multislice helical computed tomography

Ureterosciatic herniation is an extremely rare cause of ureteral obstruction, of which few cases have been published. We describe a case revealed by pyelonephritis with acute renal failure in an 81-year-old woman. After percutaneous nephrostomy tube placement and antibiotic therapy, urography and multiplanar computed tomography reconstructions of the pelvis confirmed the diagnosis. The symptoms resolved, and the hernia was then corrected surgically.     

"Endoview" project of intrapartum endoscopy.

INTRODUCTION: The change in obstetrical practices over the last decade in favor of trials of labor in patients with uterine scars has resulted in increased incidences of uterine ruptures. Although neither repeat cesarean delivery nor a trial of labor is risk free, evidence from a large multicenter study shows vaginal birth after the cesarean (VBAC) is associated with shorter hospital stays, fewer postpartum blood transfusions, and a decreased incidence of postpartum maternal fever. The uterine rupture remains the most serious complication associated with VBAC. Factors associated with uterine rupture include excessive exposure to oxytocin, dysfunctional labor, and a history of more than 1 cesarean delivery.2 Because uterine rupture may be a life-threatening event, intrapartum surveillance and the ability to perform an emergency surgery are both necessary when trial of labor is allowed. Until now, no early symptoms pathognomonic to uterine rupture had been described. We share our experiences with the novel approach to the problem - an intrapartum endoscopy. MATERIALS AND METHODS: Endoscopic examination was accomplished by using the intraoperational fiberscope (Olympus and Endoview system (Costa Mesa, CA, USA). A gas-sterilized 25-cm long fiberscope is introduced into the amniotic cavity through the cervical canal after rupture of the membranes. The distance between the fiberscope and the object varies from 3 to 50 mm. The fiberscope has a separate channel for the fluid infusion (normal saline) throughout the procedure; the surgeon looks through the eyepiece directly and exhibits control over the flexible scope. The duration of endoscopy is less than 15 minutes. The inserting of the endoscopic device is very similar to that of insertion of an intrauterine pressure catheter. The IRB Committees of both participating institutions approved the study protocol. Twenty-eight patients with an unknown or poorly documented site of the uterine scar were included in the study. An ultrasound examination had been performed on all patients prior to endoscopy to assess fetal wellbeing and placental location. The ages of the patients ranged from 21 to 38 years. Eighteen women had 1 previous cesarean delivery, and 10 had 2. The performance of intrapartum endoscopy did not interfere with fetal monitoring; 21 fetuses were monitored externally, 7 internally. Indications for previous cesarean deliveries were as follows: fetal distress in 11 cases, failure to progress in labor in 8, placenta previa in 2, and unknown in 7. Twenty-one patients delivered vaginally; 7 had had repeat cesarean deliveries. All neonates were born in satisfactory condition. The Apgar scores at 1 minute varied from 7 to 9 and at 5 minutes from 8 to 10. The integrity of the uterine wall was assessed by manual postpartum uterine exploration in each case of vaginal delivery and by visualization and palpation of the scar site in each abdominal delivery. RESULTS: The lower uterine segment and contractile portion of the anterior uterine wall were visualized successfully in all patients. In 25 patients, the presumed scar site looked totally indistinguishable from the rest of the lower uterine segment and anterior uterine wall. Two scars were identified as vertical in 2 patients who were delivered by a repeat abdominal operation. A vertical scar appears as a groove running in a cephalad-caudad direction from the lower uterine segment into the contractile portion of the anterior uterine wall. The usefulness of the intrapartum endoscopy is best demonstrated by the following case reports (2 of 28 study cases).