Clinical and technical factors in endoscopic skull base surgery associated with reconstructive success.

BACKGROUND: In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS). METHODS: ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]). RESULTS: Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing. CONCLUSIONS: Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.

Practice variation in the diagnosis of acute rejection among pediatric heart transplant centers: An analysis of the pediatric heart transplant society (PHTS) registry.

BACKGROUND: Freedom from rejection in pediatric heart transplant recipients is highly variable across centers. This study aimed to assess the center variation in methods used to diagnose rejection in the first-year post-transplant and determine the impact of this variation on patient outcomes. METHODS: The PHTS registry was queried for all rejection episodes in the first-year post-transplant (2010-2019). The primary method for rejection diagnosis was determined for each event as surveillance biopsy, echo diagnosis, or clinical. The percentage of first-year rejection events diagnosed by surveillance biopsy was used to approximate the surveillance strategy across centers. Methods of rejection diagnosis were described and patient outcomes were assessed based on surveillance biopsy utilization among centers. RESULTS: A total of 3985 patients from 56 centers were included. Of this group, 873 (22%) developed rejection within the first-year post-transplant. Surveillance biopsy was the most common method of rejection diagnosis (71.7%), but practices were highly variable across centers. The majority (73.6%) of first rejection events occurred within 3-months of transplantation. Diagnosis modality in the first-year was not independently associated with freedom from rejection, freedom from rejection with hemodynamic compromise, or overall graft survival. CONCLUSIONS: Rejection in the first-year after pediatric heart transplant occurs in 22% of patients and most commonly in the first 3 months post-transplant. Significant variation exists across centers in the methods used to diagnose rejection in pediatric heart transplant recipients, however, these variable strategies are not independently associated with freedom from rejection, rejection with hemodynamic compromise, or overall graft survival.

Variation assessment of deformable registration in stereotactic radiosurgery.

INTRODUCTION: The regular functions of CT-MRI registration include delineation of targets and organs-at-risk (OARs) in radiosurgery planning. The question of whether deformable image registration (DIR) could be applied to stereotactic radiosurgery (SRS) in its place remains a subject of debate. METHODS: This study collected data regarding 16 patients who had undergone single-fraction SRS treatment. All lesions were located close to the brainstem. CT and MRI two image sets were registered by both rigid image registration (RIR) and DIR algorithms. The contours of the OARs were drawn individually on the rigid and deformable CT-MRI image sets by qualified radiation oncologists and dosimetrists. The evaluation metrics included volume overlapping (VO), Dice similarity coefficient (DSC), and dose. The modified demons deformable algorithm (VARIAN SmartAdapt) was used for evaluation in this study. RESULTS: The mean range of VO for OARs was 0.84 ± 0.08, and DSC was 0.82 ± 0.07. The maximum average volume difference was at normal brain (17.18 ± 14.48 cm3) and the second highest was at brainstem (2.26 cm3 ± 1.18). Pearson correlation testing showed that all DIRs' OAR volumes were linearly and significantly correlated with RIRs' volume (0.679-0.992, two tailed, P << 0.001). The 100% dose was prescribed at gross tumor volume (GTV). The average maximum percent dose difference was observed in brainstem (26.54% ± 27.027), and the average mean dose difference has found at same organ (1.6% ± 1.66). CONCLUSION: The change in image-registration method definitely produces dose variance, and is significantly more what depending on the target location. The volume size of OARs, however, was not statistical significantly correlated with dose variance.

MO-A-BRB-01: Non-Coplanar Rotational Therapy by Using High Efficient Unflattened Beams.

The rapid dose fall-off from treatment target to the adjacent critical organs has been the Holy Grail for radiotherapy treatment planning. The modern treatment delivery technologies to address such goal include volumetric modulated rotational therapy, non-coplanar EVIRT beams and the use of unflattened beams to reduce the penumbra area. In this lecture, the integration of above techniques will be presented to achieve the goal of a sharp gradient dose around the target and also the discussion of middle to low dose volumes. Use of volumetric modulated rotational therapy by multiple non-coplanar arcs is an idea treatment modality to focus the high dose in the target area while spreading the low dose to even larger volume to reduce the middle range dose to surrounding critical organs. This is especially important for SBRT treatment plans since the fraction dose is much higher than the traditional fraction schema. The challenges we face today are 1. the gantry-couch (patient) collision issue for non-coplanar beam angles, 2. the treatment delivery efficiency due to multiple arc rotations and 3. the massive inverse optimization computation for multiple rotational arcs can be resource intensive and time consuming for treatment plan systems. It might not be easy to resolve all the challenges at one time. However, the high efficient unflattened beam can certainly improve the delivery speed by reducing the beam- on time and this, again, is essential to SBRT patients with high fractional dose. In this lecture, the non-coplanar rotational therapy treatment planning techniques will be presented and be evaluated by using comformality index, gradient index as well as dose volume histogram comparison. The differences in treatment delivery time will be tabulated and compared. At the end, the high-medium-low dose volumes will be illustrated with radiobiological models for the philosophy of sun tanned versus sun burned. LEARNING OBJECTIVES: 1. Understand treatment plan and dose gradient advantages of using non- coplanar rotational therapy 2. Understand potential delivery efficiency by using unflattened beams for multiple non-coplanar rotational beams 3. Understand sun tanned versus sun burned: the low dose volume and integrated dose.

Environmental lead exposure and cognitive function in community-dwelling older adults.

OBJECTIVE: To determine if long-term exposure to high levels of lead in the environment is associated with decrements in cognitive ability in older Americans. METHODS: We completed a cross-sectional analysis using multiple linear regression to evaluate associations of recent (in blood) and cumulative (in tibia) lead dose with cognitive function in 991 sociodemographically diverse, community-dwelling adults, aged 50 to 70 years, randomly selected from 65 contiguous neighborhoods in Baltimore, MD. Tibia lead was measured with (109)Cd induced K-shell X-ray fluorescence. Seven summary measures of cognitive function were created based on standard tests in these domains: language, processing speed, eye-hand coordination, executive functioning, verbal memory and learning, visual memory, and visuoconstruction. RESULTS: The mean (SD) blood lead level was 3.5 (2.2) microg/dL and tibia lead level was 18.7 (11.2) microg/g. Higher tibia lead levels were consistently associated with worse cognitive function in all seven domains after adjusting for age, sex, APOE-epsilon4, and testing technician (six domains p

Dose effects of guide wires for catheter-based intravascular brachytherapy.

PURPOSE: Guide wires with high torquability and steerability are commonly used to navigate through a tortuous and/or branching arterial tree in a catheter-based intravascular brachytherapy procedure. The dosimetric effects due to the presence of metallic guide wires have not been addressed. This work investigates these dose effects for the three most commonly used beta and gamma sources (90Sr, 32P, and 192Ir). METHODS AND MATERIALS: The EGS4 Monte Carlo codes were used to calculate the dose distributions for the 90Sr(NOVOSTE), 32P (Guidant), and 192Ir (BEST Ind.) with and without a guide wire in place. Energy spectra for particles exiting the sources were calculated from the full phase-space data obtained from the Monte Carlo simulations of the source constructions. Guide wires of various thicknesses and compositions were studied. RESULTS: The dose perturbations due to the presence of guide wires were found to be far more significant for the 90Sr/90Y and 32P beta sources than those for the 192Ir gamma source. Because of the attenuation by the guide wires, a dose reduction of up to 60% behind a guide wire was observed for the beta sources, whereas the dose perturbation was found to be negligible for the gamma source. For a beta source, the dose perturbations depend on the thickness and the material of the guide wire. When the region behind a guide wire is part of an intravascular brachytherapy target, the presence of the guide wire results in a significant underdosing for beta sources. The underdosed region can extend a few mm behind the guide wire and up to 1 mm in other directions. CONCLUSION: Significant dose perturbations by the presence of a metallic guide wire have been found in catheter-based intravascular brachytherapy using beta sources. The dose effects should be considered in the dose prescription and/or in analyzing the treatment outcome for beta sources. Such precautions are not necessary if using a gamma source.

Monte Carlo dose verification for intensity-modulated arc therapy.

Intensity-modulated arc therapy (IMAT), a technique which combines beam rotation and dynamic multileaf collimation, has been implemented in our clinic. Dosimetric errors can be created by the inability of the planning system to accurately account for the effects of tissue inhomogeneities and physical characteristics of the multileaf collimator (MLC). The objective of this study is to explore the use of Monte Carlo (MC) simulation for IMAT dose verification. The BEAM/DOSXYZ Monte Carlo system was implemented to perform dose verification for the IMAT treatment. The implementation includes the simulation of the linac head/MLC (Elekta SL20), the conversion of patient CT images and beam arrangement for 3D dose calculation, the calculation of gantry rotation and leaf motion by a series of static beams and the development of software to automate the entire MC process. The MC calculations were verified by measurements for conventional beam settings. The agreement was within 2%. The IMAT dose distributions generated by a commercial forward planning system (RenderPlan. Elekta) were compared with those calculated by the MC package. For the cases studied, discrepancies of over 10% were found between the MC and the RenderPlan dose calculations. These discrepancies were due in part to the inaccurate dose calculation of the RenderPlan system. The computation time for the IMAT MC calculation was in the range of 20-80 min on 15 Pentium-Ill computers. The MC method was also useful in verifying the beam apertures used in the IMAT treatments.

Dosimetric characteristics of dynamic wedged fields: a Monte Carlo study.

We have developed a Monte Carlo (MC) technique using the EGS4/BEAM system to calculate dosimetric characteristics of dynamic wedges (DW) for photon beam radiotherapy. The simulation of DW was accomplished by weighting the history numbers of the electrons, which are incident on the target in accordance with the segmented treatment table. Calculations were performed for DW with wedge angles ranging from 15 degrees to 60 degrees as well as for open fields with different field sizes for both degrees 6 and 18 MV beams. The MC-calculated percentage depth dose (PDD) and beam profiles agreed with the measurements within +/- 2% (of the dose maximum along the beam axis) or +/- 2 mm in high dose gradient region. The DW slightly affects energy spectra of photons and contaminating electrons. These slight changes have no significant effects on PDD as compared to the open field. The MC-calculated dynamic wedge factors agree with the measurements within +/- 2%. The MC method enables us to provide more detailed beam characteristics for DW fields than a measurement method. This beam characteristic includes photon energy spectra, mean energy, spectra of contaminating electrons and effects of moving jaw on off-axis beam quality. These data are potentially important for treatment planning involving dynamic wedges.

Riboflavin transport by isolated perfused rabbit renal proximal tubules.

Rabbit renal proximal tubular transport of riboflavin (RF) was examined by using the in vitro isolated tubule perfusion technique. We found that proximal tubules actively reabsorbed (J(lb)) and secreted (J(bl)) RF. At 0.1 microM RF concentration, J(bl) was significantly higher than J(lb), resulting in a net secretion. This net secretion of RF was decreased at 0.01 microM RF concentration and increased at 1 microM RF concentration. Both J(lb) and J(bl) were inhibited by lowering temperature or by adding iodoacetate, a metabolic inhibitor, and lumichrome, an RF analog, suggesting the involvement of carrier-mediated transport mechanisms. J(bl) was inhibited by probenecid, an anion transport inhibitor, and by para-aminohippuric acid, an organic anion, suggesting the relevance of RF secretion to renal organic anion transport. J(bl) was also inhibited by alkaline pH (8.0) and by the calmodulin inhibitor trifluoperazine, indicating the influence of pH and Ca(2+)/calmodulin-dependent pathway on RF secretion. Finally, we found that addition of chlorpromazine, a phenothiazine derivative, inhibited both J(lb) and J(bl), raising the concern about the nutritional status in patients receiving such a type of medication.

A descriptive study of an epidemic of poisoning caused by heroin adulterated with scopolamine.

OBJECTIVE: Adulterants, contaminants, and diluents are all examples of additives to street drugs. Some of these additives may be pharmacologically active; however, it is unusual for them to cause toxic side effects. In the spring of 1995, a new form of heroin appeared in New York City, spreading to other East Coast cities, that was adulterated with scopolamine. It caused severe anticholinergic toxicity in heroin users with patients often presenting to emergency departments in great numbers. This is a report of the demographics and clinical characteristics of the epidemic. METHODS: A combination of prospective and retrospective data collection from the New York City, New Jersey, Delaware Valley, and Maryland Poison Centers. The primary measurements were age, sex, route of drug use, vital signs, signs and symptoms, disposition, and treatment. RESULTS: Of the 370 cases reported to the participating poison centers, 129 were excluded from the final analysis because of insufficient data. Of the patients who used this product, 55% presented with signs and symptoms of heroin toxicity but then became severely agitated with anticholinergic symptoms when naloxone was used to reverse respiratory depression. Nasal insufflation was the route of administration in 34% of the cases. Seizures were rare (3%). Ninety percent required admission, and half were admitted to a critical care unit. CONCLUSIONS: Adulteration of street drugs can lead to toxic epidemics. Poison centers are essential for identification of these trends and are the primary source of information on diagnosis and treatment.

Expression and prognostic significance of proliferating cell nuclear antigen and Ki-67 in malignant ovarian germ cell tumors.

BACKGROUND: Both proliferating cell nuclear antigen (PCNA) and Ki-67 are proliferative markers known to correlate with the cell proliferative state. The aim of this study was to evaluate the usefulness of PCNA and Ki-67 immunoreactivity in the assessment of clinicopathologic features and prognosis in patients with malignant ovarian germ cell tumors. METHODS: Thirty-one patients with surgically resected malignant ovarian germ cell tumors were investigated. The clinicopathologic features and survival data of these patients were recorded. Immunohistochemical staining with monoclonal antibodies (PC 10 for PCNA, and MIB-1 for Ki-67) were performed on paraffin embedded tissue from each patient. The correlation of the immunoreactivity of these two markers with the clinicopathologic features and prognosis were studied. RESULTS: All of the tumors were positive for PCNA and Ki-67, but the intensity of expression varied widely. The immunoreactivity in each tumor was also heterogeneous. The scoring of PCNA and Ki-67 was determined by a semiquantitative method. Both advanced tumor stage (stages III and IV) and high PCNA score (scores 3 and 4) indicated a poorer prognosis for survival than did early stage (stages I and II) and a low PCNA score (scores 1 and 2) (p = 0.017 and p = 0.008, respectively). In addition, the proportion of tumor relapse and tumor-induced death was more accurately predicted by PCNA and Ki-67 scoring than by tumor staging (chi 2 = 0.3159, chi 2 = 0.7186 and chi 2 = 1.9689, respectively). CONCLUSIONS: PCNA and Ki-67 proliferative markers appear promising to differentiate patients into low- and high-risk groups. In the presence of a high PCNA or Ki-67 score, aggressive postoperative chemotherapy is warranted, even if the disease is in a very early stage.

Stages at presentation, prognostic factors, and outcome of breast cancer in males.

BACKGROUND: In order to support or refute conventional notions of breast cancer in males as a late-presenting disease associated with a worse prognosis than the same disease in females, we reviewed a recent, multi-institutional experience. METHODS: A case series from three area hospital system cancer data bases was reviewed. Demographics, pathology, stages at presentation, and treatment were determined from the data set and correlated with outcomes (recurrence/survival). RESULTS: Fifty-four patients (mean age 64.5, SD = 12.8) were identified; half of the tumors were stage T0 or T1, 62% were node negative (N0), and 57% had an American Joint Committee on Cancer (AJCC) stage grouping of IIA or less. Eighty-five percent of tumors examined expressed hormone receptors. There were no local-only recurrences in the 50 cases resected for cure, including 5 cases of minimal breast cancer treated by lumpectomy only. Five- and 10-year overall disease-free survival was AJCC stage related: 100% and 71%, respectively, for early stage (0-IIA) disease, and 71% and 20%, respectively, for advanced (IIB-IV) stage (P = 0.0051 by log-rank). Only AJCC stage and its components (tumor size, nodal status, presence of metastases) correlated with survival by multivariate analysis; other factors such as age, family history, and presenting symptoms/signs did not. CONCLUSIONS: The majority of breast cancers in males present at early stages and are hormone receptor positive. In contrast to older notions of this disease as uniformly aggressive, we conclude that prognostic factors and stage-for-stage outcomes for breast cancer in males are similar to those published for the disease in females.

Calculation of head scatter factors at isocenter or at center of field for any arbitrary jaw setting.

The purpose of this work is to calculate the head scatter factors for any arbitrary jaw setting by using two different semi-empirical methods. The head scatter factor at the center of field (COF) for any arbitrary jaw setting can be defined as H(COF)(X1,X2,Y1,Y2,r)=DairCOF(XI1,X2,Y1,Y2,r)/ [Dair(5,5,5,5,0)*OAR(r)], where X1, X2, Y1, and Y2 are the jaw positions; r is the distance between COF and isocenter (IC); OAR(r) is the Off-Axis-Ratio; DairCOF(X1,X2,Y1,Y2,r) is the dose in air measured at COF; Dair(5,5,5,5,0) is the dose in air measured at IC for the 10 x 10 cm2 field. In certain clinical situations, doses are prescribed at IC instead of COF for asymmetric fields. In these cases, head scatter factors should be determined at IC. It is found that the head scatter factors at IC for asymmetric fields [H(IC)(X1,X2,Y1,Y2)] are lower than H(COF)(X1,X2,Y1,Y2,r) for the same jaw setting by up to 4%. The values of H(IC)(X1,X2,Y1,Y2) and H(COF)(X1,X2,Y1,Y2,r) for a variety of jaw settings were measured using a miniphantom of 3-cm diameter for a 6- and a 18-MV photon beams. An equivalent square formula, derived presently at the source plane for any jaw setting, was used to calculate H(COF)(X1,X2,Y1,Y2,r). The calculation and the measurement agree within +/-1% (+/-0.5% for most clinical situations). To calculate H(IC)(X1,X2,Y1,Y2), we have generalized the Day's "quarter-field" method, i.e., H(IC)(X1,X2,Y1,Y2) = [H(X1,X1,Y1,Y1) + H(X1,X1,Y2,Y2) + H(X2,X2,Y1,Y1) + H(X2,X2,Y2,Y2)]/4. We found that the calculation and the measurement agree within +/-0.8% for the beams studied.

Age-related defects in spatial memory are correlated with defects in the late phase of hippocampal long-term potentiation in vitro and are attenuated by drugs that enhance the cAMP signaling pathway.

To study the physiological and molecular mechanisms of age-related memory loss, we assessed spatial memory in C57BL/B6 mice from different age cohorts and then measured in vitro the late phase of hippocampal long-term potentiation (L-LTP). Most young mice acquired the spatial task, whereas only a minority of aged mice did. Aged mice not only made significantly more errors but also exhibited greater individual differences. Slices from the hippocampus of aged mice exhibited significantly reduced L-LTP, and this was significantly and negatively correlated with errors in memory. Because L-LTP depends on cAMP activation, we examined whether drugs that enhanced cAMP would attenuate the L-LTP and memory defects. Both dopamine D1/D5 receptor agonists, which are positively coupled to adenylyl cyclase, and a cAMP phosphodiesterase inhibitor ameliorated the physiological as well as the memory defects, consistent with the idea that a cAMP-protein kinase A-dependent signaling pathway is defective in age-related spatial memory loss.

Shorter survival in advanced human immunodeficiency virus type 1 infection is more closely associated with T lymphocyte activation than with plasma virus burden or virus chemokine coreceptor usage.

To define predictors of survival time in late human immunodeficiency virus type 1 (HIV-1) disease, long- and short-duration survivors were studied after their CD4+ T cells fell to

A clinicopathologic study of mucinous gastric carcinoma including multivariate analysis.

BACKGROUND: Mucinous gastric carcinoma (MGC) is a rare subtype of gastric adenocarcinoma, and its clinical and pathologic features are still controversial. To clarify the significance of this subtype of carcinoma, the authors conducted a case-control study to investigate the clinicopathologic characteristics of MGC and determine whether this mucin-producing histologic type is associated with a worse prognosis than other gastric carcinomas. METHODS: Twenty-two cases of MGC and 46 patients with nonmucinous gastric carcinoma (NGC) were included. Patients were evaluated on the basis of age, gender, tumor size, location, depth of tumor invasion, histologic differentiation, lymph node involvement, organ metastasis, stage at presentation, surgical curability, adjuvant chemotherapy and radiation therapy. To determine whether the MGC itself was an independent prognostic factor, a multivariate analysis was performed with the Cox proportional hazards model. RESULTS: The MGC patients were found to have larger tumors (P < 0.001), tumors more often located in the upper stomach (P < 0.05), more serosal invasion (P < 0.05), more lymph node involvement (P < 0.05), greater frequency of advanced stage disease (P < 0.01), and lower 5-year survival rates (P < 0.05) than NGC patients. There was no significant correlation between the subtypes of differentiation of MGC and other data, including the prognosis. Multivariate analysis showed that clinically important predictive factors were serosal invasion and disease stage at diagnosis. The mucinous histologic type itself was not an independent factor for poor prognosis. CONCLUSIONS: The overall survival rate for patients with MGC was worse than that for patients with NGC. The poor prognosis was correlated with more advanced stage at diagnosis and more frequent serosal invasion, not with the mucinous histologic type.

Accurate evaluation of palpable breast masses by the triple test score.

BACKGROUND: We previously reported that the triple test (physical examination, mammography, and fine needle aspiration) for palpable breast masses yields 100% diagnostic accuracy when all 3 components are concordant (all benign or all malignant). However, 40% of cases are nonconcordant and require open biopsy. OBJECTIVE: To evaluate our experience with the triple test to develop a method to further limit the need for surgical biopsy. DESIGN: Diagnostic test study. SETTING: University hospital multidisciplinary breast clinic. PATIENTS: Two hundred fifty-nine patients with 261 palpable breast masses studied between 1991 and 1997. INTERVENTION: The triple test was prospectively applied to each breast mass. Each component of the triple test was assigned 1, 2, or 3 points for a benign, suspicious, or malignant result, respectively, yielding a total triple test score (TTS). MAIN OUTCOME MEASURES: The TTS was correlated with subsequent histopathologic examination results. RESULTS: Eighty-eight masses had a TTS of more than 6 points; all had malignant histopathologic characteristics. One hundred fifty-two masses had a TTS of 4 points or lower; all were benign. In both groups, diagnostic accuracy and predictive value were 100%, with P<.001. Twenty-one masses had a TTS of 5 points; of these, 13 (62%) were benign and 8 (38%) were malignant. CONCLUSIONS: The TTS reliably guides evaluation and treatment of palpable breast masses. Masses that score 6 points or higher are malignant and should undergo definitive therapy; masses that score 4 points or lower are benign and may be clinically followed up. Only those masses that score 5 points (8% of our database) require open biopsy.

Intraluminal mucin pool in mucinous gastric adenocarcinoma: a case report.

Mucinous gastric carcinoma is a rare pathologic subtype of gastric adenocarcinoma. Whether the mucin behaves aggressively as in mucinous colorectal carcinoma is still controversial. Most mucinous gastric carcinomas are diagnosed from surgical specimens. The mucinous gastric carcinoma in this case report was discovered preoperatively according to its characteristic presentation. An upper gastrointestinal endoscopic examination showed a round protruding tumor of greater than 4 cm in size on the mid-body of the stomach; it had an uneven, friable and shiny surface. The surface was coated with a sticky layer of mucin-like substance, which persisted even after the aspiration of the gastric juice. Endoscopic ultrasonography (EUS) revealed a large heterogeneous hyperechoic tumor mass, originating from the mucosal and submucosal layers, on the body of the stomach. The mass was covered with a thick layer of hypoechoic amorphous substance. Hence, a mucin-producing tumor was suspected. Subsequent surgical biopsy proved the mass to be a moderately differentiated mucinous adenocarcinoma. This case illustrates the first endoscopic ultrasonographic report of an intraluminal mucin pool as a hypoechoic substance, which is quite different from the hyperechoic presentation of intramural mucin lakes. In preoperative evaluation, EUS is not only important for determining the depth of tumor invasion, but it is also useful in differentiating mucinous gastric carcinoma from nonmucinous gastric carcinoma.

Preoperative evaluation and postoperative prediction of hemostatic function with thromboelastography in patients undergoing redo cardiac surgery.

BACKGROUND: Patients who receive cardiac procedures, in particular "redo" ones, often suffer complications from massive bleeding, largely due to bypass-induced coagulopathies. Cardiopulmonary bypass (CPB) may cause damage of the blood components, both in terms of quality and quantity. In order to investigate the qualitative changes of blood constituents with special regard to coagulation resulting from the complex insult of previous cardiac surgery, thromboelastography (TEG) was used to analyze the whole clotting process. METHODS: Seventy-four patients who underwent cardiac surgery with CPB were prospectively studied. Of them, 32 patients received "redo" cardiac surgery. Blood samples for routine laboratory coagulation tests (RCT) and TEG examination were drawn before and after cardiopulmonary bypass. Clinically significant bleeding was defined if the chest tube drainage was greater than 100 ml/h for 3 consecutive h or greater than 300 ml in 1 h during the first 8 h after surgery. Prebypass and postbypass coagulation parameters were compared and the percentage of accuracy, false positive and false negative rate were deduced from calculation. RESULTS: In the TEG tracings, preoperative alpha angle and maximum amplitude were significantly decreased in the "redo" group when compared with primary group, indicating less competent platelet function and platelet-fibrin interaction. Lower platelet count was also found by conventional coagulation tests in "redo" patients. Postoperatively, higher percentage of excessive hemorrhage was also noted in the "redo" group (42.8% vs. 27.5% in primary group). However, a much lower predictive accuracy was found in "redo" patients in comparison with primary cardiac patients (53.5% vs. 90%). CONCLUSIONS: We concluded that thromboelastography failed to predict postoperative hemorrhage in "redo" cardiac patients and the graphic recordings derived could not be treated as a guide of transfusion therapy. We thought that inferior preoperative hemostatic status and severer coagulopathy might be responsible for the differences between "redo" and primary cardiac patients.