Basics of Deep Learning: A Radiologist's Guide to Understanding Published Radiology Articles on Deep Learning

Artificial intelligence has been applied to many industries, including medicine. Among the various techniques in artificial intelligence, deep learning has attained the highest popularity in medical imaging in recent years. Many articles on deep learning have been published in radiologic journals. However, radiologists may have difficulty in understanding and interpreting these studies because the study methods of deep learning differ from those of traditional radiology. This review article aims to explain the concepts and terms that are frequently used in deep learning radiology articles, facilitating general radiologists' understanding.

Gastrointestinal cancer risk in patients with a family history of gastrointestinal cancer

Background/Aims

This study was performed to evaluate the relationship between family history of gastrointestinal (GI) cancers and incidence of any GI cancer in the Korean population.

Methods

Between January 2015 and July 2016, 711 GI cancer patients and 849 controls in 16 hospitals in Korea were enrolled. Personal medical histories, life styles, and family history of GI cancers were collected via questionnaire.

Results

There was a significant difference in the incidence of family history of GI cancer between GI cancer patients and controls (p=0.002). Patients with family history of GI cancer tended to be diagnosed as GI cancer at younger age than those without family history (p=0.016). The family members of GI cancer patients who were diagnosed before 50 years of age were more frequently diagnosed as GI cancer before the age of 50 years (p=0.017). After adjusting for major confounding factors, age (adjusted odds ratio [AOR] 1.065, 95% confidence interval [CI]; 1.053-1.076), male gender (AOR 2.270, 95% CI; 1.618-3.184), smoking (AOR 1.570, 95% CI; 1.130-2.182), and sibling's history of GI cancer (AOR 1.973, 95% CI; 1.246-3.126) remained independently associated with GI cancers.

Conclusions

GI cancer patients tended to have a first relative with a history of concordant GI cancer. Personal factors (old age and male) and lifestyle (smoking) contribute to the development of GI cancer, independently. Individuals with high risk for GI cancers may be advised to undergo screening at an earlier age.

Preparedness of Young Male Physicians for Biological Terrorism and Warfare in South Korea

Introduction

The events of 11th September 2001, and the subsequent anthrax attacks in the United States brought the threat of bioterrorism to the forefront of concern for public health departments. Moreover, the rising confrontation between North and South Korea emphasizes the possibility of aggression with biological weapons and our vulnerability to bioterrorism. While the importance of physicians' interests and management ability is becoming more critical, no studies have yet been undertaken in Korea to assess whether primary care physicians are well informed and capable of managing bioterrorism. This study evaluates the awareness and response of young male physicians to potential bioterrorism in South Korea.

Method

A total of 692 young male physicians completed the knowledge and awareness survey during the education period of military service on 9th April 2005.

Results

Forty-five percent of the participants responded that the possibility of biological warfare in Korea was high. The level of bioterrorism knowledge, however, was low. Eighty-seven percent acknowledged the necessity of education and training for bioterrorism, and 69.9% were willing to accept education and training in bioterrorism preparedness.

Conclusion

These findings suggest that young physicians should receive continuous education and training to improve preparedness for biological terrorism and warfare in South Korea.

Assessment of the Risk of Colorectal Cancer Survivors Developing a Second Primary Pancreatic Cancer

BACKGROUND/AIMS

We aimed to investigate the incidence of second primary pancreatic cancer (PC) after colorectal cancer (CRC) and to identify risk factors associated with subsequent PC.

METHODS

The observed incidence of a subsequent PC in patients with CRC was standardized using a population with CRC from the Korean Central Cancer Registry (KCCR). The expected incidence rate of PC was obtained by assuming that the select group experienced the same cancer incidence as the corresponding general population in the KCCR.

RESULTS

The registry included 4,822 patients with CRC aged 45 to 74 years, representing 16,725.1 person-years of follow-up. Thirteen patients (0.3%) were diagnosed with a subsequent PC, and the overall age-adjusted incidence of second primary PC was 269.6 per 100,000 cases. In contrast, the overall incidence of primary PC in the general population was 18.68 per 100,000 individuals. The standardized incidence ratio of subsequent PC was 14.44, which was significantly higher in patients with CRC than in the general population. Sex, diabetes mellitus, smoking, body mass index, and a history of receiving chemotherapy as a treatment for CRC did not increase the risk of subsequent development of PC.

CONCLUSIONS

The risk of a second primary PC was higher in patients with CRC. Further studies are needed to identify the risk factors and generate a screening strategy for cancer survivors.

Metastatic endophthalmitis and thyroid abscess complicating Klebsiella pneumoniae liver abscess

The thyroid is resistant to infection due to its anatomical and physiological characteristics. We present a rare case of invasive liver abscess with metastatic thyroid abscess and endogenous endophthalmitis in a previously healthy 55-year-old female patient without diabetes or other medical illness. This report raises an important question of the virulence of Klebsiella pneumoniae as an increasingly common causative agent of liver abscess.

The prevalence and impact of sarcopenia on degenerative lumbar spinal stenosis

AIMS

The purpose of this study was to investigate the prevalence of sarcopenia and to examine its impact on patients with degenerative lumbar spinal stenosis (DLSS).

PATIENTS AND METHODS

This case-control study included two groups: one group consisting of patients with DLSS and a second group of control subjects without low back or neck pain and related leg pain. Five control cases were randomly selected and matched by age and gender (n = 77 cases and n = 385 controls) for each DLSS case. Appendicular muscle mass, hand-grip strength, sit-to-stand test, timed up and go (TUG) test, and clinical outcomes, including the Oswestry Disability Index (ODI) scores and the EuroQol EQ-5D were compared between the two groups.

RESULTS

The prevalence of sarcopenia, as defined by hand-grip strength, was significantly higher in the DLSS group (24%) when compared with the age- and gender-matched control group (12%) (p = 0.004). In the DLSS group, the sarcopenia subgroup demonstrated inferior results for the TUG test and ODI scores when compared with the non-sarcopenia subgroup (p = 0.006 and p = 0.039, respectively) after adjusting for age and gender.

CONCLUSION

This study demonstrated a higher prevalence of sarcopenia in patients with DLSS and highlighted its negative effect on clinical outcomes. Cite this article: Bone Joint J 2016;98-B:1093-8.

Anti-inflammatory effects of simvastatin in nonsteroidal anti-inflammatory drugs-induced small bowel injury

Small bowel injury can occur as the result of a multifaceted process that includes increased acid secretion, generation of reactive oxygen species, and cyclooxygenase inhibition. However, no effective medication for small bowel ulceration is available. Simvastatin is an important lipid-lowering agent with anti-inflammatory activity. We aimed to validate the effects of simvastatin in vitro and in vivo. In presence or absence of simvastatin, IEC-6 small bowel cell line with 50 ng/ml of tumor nectosis factor α (TNF-α) was investigated by western blotting, qRT-PCR, and DCF-DA assay. In addition, an in vivo study of nonsteroidal anti-inflammatory drugs (NSAID)-induced small bowel inflammation was performed using 7-week-old specific-pathogen-free (SPF) male C57BL/6 mice. Simvastatin treatment reduced the mRNA levels of interleukin-6 and interleukin-8 by approximately 50% in TNF-α-stimulated IEC-6 cells. Treatment with a combination of 50 ng/ml TNF-α and μM simvastatin decreased activation of Akt, IκBα, and nuclear factor-κB p65 level in IEC-6 cells. By DCF-DA staining, intracellular reactive oxygen species (ROS) production was increased in TNF-α-stimulated cells, and treatment with simvastatin decreased the level of ROS. In addition, in vivo mouse model of NSAID-induced small bowel inflammation, the administration of simvastatin reduced the number of small bowel hemorrhagic lesions and the level of ROS production as determined by gross examination and 8-hydroxydeoxyguanosine immunohistochemistry of small bowel tissue, respectively. Simvastatin reduced NSAID-induced injuries by both suppression of ROS generation and modulation of inflammatory cytokines in vitro and in vivo. Therefore, simvastatin, an HMG-CoA reductase inhibitor, has potential as a prophylactic and therapeutic agent for NSAID-induced small bowel injury.

Simultaneous removal of rotavirus and adenovirus from artificial ground water using hydrochar derived from swine feces

Hydrothermal carbonization technology can convert fecal waste into a valuable carbonaceous product referred to as hydrochar. We investigated the potential of fecal waste-derived hydrochar as an adsorbent for virus removal in water treatment. Swine feces was hydrothermally treated under two conditions: at 180 °C for 2 h and 230 °C for 7 h. The resulting solid products (hydrochar) were evaluated as virus adsorbents in water treatment. Simultaneous removal of pathogenic rotavirus (RV) and human adenovirus (HAdV) was investigated using a sand column set-up of 10 cm bed height with and without hydrochar supplement (1.5%, w/w). The removal efficiency of both viruses in a hydrochar-amended column was >3 log (complete removal). The amount of virus released in deionized water when flushed into the virus-retaining columns indicated that the secondary energy minimum played a more important role in RV retention than that of HAdV. Zeta-potential and hydrophobicity measurements on hydrochar materials indicated that the improved virus removal performance of hydrochar-amended columns was induced by the provision of extra hydrophobic surfaces. This study provides evidence that fecal waste-derived hydrochar can be used as a competent virus adsorbent.

[A Case of Isolated Leptomeningeal Carcinomatosis from Advanced Gastric Cancer]

Leptomeningeal carcinomatosis (LMC) is rare metastatic form of gastric cancer. Most cases are diagnosed in the final stage after multiple distant metastasis. An 84-year-old woman was admitted with melena, headache and vomiting. Esophagogastroduodenoscopy showed an ulceroinfiltrating lesion at the stomach (Borrmann class III), and biopsy revealed a signet ring cell carcinoma. The abdominal-pelvic CT showed no evidence of metastasis. A sudden decrease of consciousness was noted, but the brain CT showed no active lesion while the brain MRI revealed enhancement of leptomeninges. A lumbar puncture was performed and the cerebrospinal fluid study revealed malignant neoplastic cells. With family consent, no further evaluation and treatment were administered and she died six weeks after the diagnosis of gastric cancer. We report an extremely rare case of a patient who initially presented with neurologic symptoms, and was diagnosed LMC from advanced gastric cancer without any evidence of metastasis in abdomen and pelvis.

Prognostic Value of Labyrinthine 3D-FLAIR Abnormalities in Idiopathic Sudden Sensorineural Hearing Loss

BACKGROUND AND PURPOSE

According to recent research, modern MR imaging can detect the presense of abnormalities on labyrinthine. Our aim was to report the patterns and prognostic role of abnormal findings on labyrinthine imaging in patients with sudden sensorineural hearing loss.

MATERIALS AND METHODS

This study comprised 113 patients who were diagnosed with unilateral sudden sensorineural hearing loss and underwent 3T MR imaging, including pre-/postcontrast 3D fluid-attenuated inversion recovery and T1-weighted imaging. We analyzed abnormalities on MR imaging and correlated them with audiometric results.

RESULTS

Thirty-one (27%) patients showed abnormal findings on labyrinthine MR imaging in the affected ear. The initial/final hearing levels of the MRI+ group (91 ± 25/73 ± 27 dB hearing loss) were significantly worse than those of the MRI- group (69 ± 30/48 ± 24 dB hearing loss). The incidence of abnormalities on labyrinthine MR imaging was significantly lower (3 of 40, 8%) in 40 patients with initial mild-to-moderate hearing loss than in those with profound hearing loss (16 of 34, 47%). Considering hearing improvement by the Siegel criteria, the rate of complete or partial recovery was significantly higher in the MRI- group (34%) than in the MRI+ group (10%). In patients with initial severe or profound hearing loss, the MRI- group showed greater hearing improvement (38 ± 21 dB) than the MRI+ group (23 ± 22 dB).

CONCLUSIONS

Abnormalities on labyrinthine MR imaging were found in 27% of patients with sudden sensorineural hearing loss. The initial hearing loss was worse in the MRI+ group than in the MRI- group. In patients with initial severe and profound hearing loss, the presence of abnormalities on labyrinthine MR imaging indicated a poor prognosis.

Spin-induced band modifications of graphene through intercalation of magnetic iron atoms

Intercalation of magnetic iron atoms through graphene formed on the SiC(0001) surface is found to induce significant changes in the electronic properties of graphene due mainly to the Fe-induced asymmetries in charge as well as spin distribution. From our synchrotron-based photoelectron spectroscopy data together with ab initio calculations, we observe that the Fe-induced charge asymmetry results in the formation of a quasi-free-standing bilayer graphene while the spin asymmetry drives multiple spin-split bands. We find that Fe adatoms are best intercalated upon annealing at 600 °C, exhibiting split linear π-bands, characteristic of a bilayer graphene, but much diffused. Subsequent changes in the C 1s, Si 2p, and Fe 3p core levels are consistently described in terms of Fe-intercalation. Our calculations together with a spin-dependent tight binding model ascribe the diffuse nature of the π-bands to the multiple spin-split bands originated from the spin-injected carbon atoms residing only in the lower graphene layer.

Long-term results of thoracoscopic thymectomy for thymoma without myasthenia gravis

OBJECTIVE

To compare the feasibility and safety of thoracoscopic thymectomy with conventional sternotomy thymectomy for thymoma without myasthenia gravis.

METHODS

Data from 70 patients diagnosed with thymoma, who underwent thoracoscopic thymectomy (n = 25, Group T) or sternotomy thymectomy (n = 45, Group S) between March 2002 and March 2008, were retrospectively evaluated.

RESULTS

Mean follow-up durations were 78.0 ± 21.9 months and 70.0 ± 23.6 months in Groups T and S, respectively. No deaths occurred in Group T; seven deaths occurred in Group S, all > 1 month post follow-up. Durations of chest intubation and hospitalization were significantly shorter in Group T than in Group S. No significant between-group difference in the incidence of operative complications was observed. Tumour recurrence-free rates at 5 and 7 years postsurgery were 96% (both years) in Group T and 95% (both years) in Group S.

CONCLUSIONS

Long-term follow-up indicates that thoracoscopic thymectomy for thymoma without myasthenia gravis is effective and is well tolerated, and associated with low rates of operative complications and recurrence.

Development of low cost two-step reverse transcription-quantitative polymerase chain reaction assays for rotavirus detection in foul surface water drains

Commercial kits to determine RNA concentrations are expensive, and sometimes too expensive for laboratories working with tight budgets, especially those in developing countries. We developed, tested, and evaluated two home-made two-step reverse transcription-quantitative polymerase chain reaction assays aimed to detect rotavirus in surface water samples. A commercial one-step master kit was used for comparison. Our results indicated that the efficiency of the home-made assays was comparable to the commercial kit. Furthermore, the lowest detection limit of all assays corresponded to 10⁻⁰·² TCID₅₀ (50 % tissue Culture Infective Dose) per ml. The home-made assays were able to detect rotavirus concentrations in complex surface waters in a slum area in Kampala (Uganda) and their performance was comparable to the commercial kit. The total costs of the two home-made assays was 11 times less than the selected commercial kit. Although preparing home-made assays is more time consuming, the assays can be useful for cases in which consumable costs are more important than personnel costs.

Genomic copy concentrations of selected waterborne viruses in a slum environment in Kampala, Uganda

The presence of viruses in a slum environment where sanitation is poor is a major concern. However, little is known of their occurrence and genomic copy concentration in the slum environment. The main objective of this study was to determine the genomic copy concentrations of human adenoviruses F and G, Rotavirus (RV), Hepatitis A virus (HAV), Hepatitis E virus (HEV) and human adenovirus species A,C,D,E, and F (HAdV-ACDEF) in Bwaise III, a typical slum in Kampala, Uganda. Forty-one samples from surface water, grey water and ground water were collected from 30 sampling locations. The virus particles were recovered by glass wool filtration with elution using beef extract. DNA and RNA viruses were detected by the real time quantitative polymerase chain reaction (qPCR) and the reverse transcription-qPCR (RT-qPCR), respectively. HAdV-F and G were detected in 70.7% of the samples with concentrations up to 2.65 × 10(1) genomic copies per mL (gc mL(-1)). RV and HAV were detected in 60.9% and 17.1% of the samples, respectively. The maximum concentration of RV was 1.87 × 10(2)gc mL(-1). In addition, 78% of the samples tested positive for the HAdV-ACDEF, but all samples tested negative for HEV. These new data are essential for quantitative microbial risk assessment, and for understanding the effects of environmental pollution in slums.

Microscopic schistocyte determination according to International Council for Standardization in Hematology recommendations in various diseases

INTRODUCTION

Recently, a consensus report for microscopic schistocyte determination was prepared by International Council for Standardization in Hematology (ICSH). ICSH focused on diagnosis of thrombocytopenic purpura (TTP)/hemolytic uremic syndrome (HUS). We aimed to reanalyze schistocytes according to ICSH recommendations, to study diseases other than TTP/HUS related to the schistocytes, and to compare the percentage of schistocytes among the various diseases.

METHODS

We retrieved all reported cases of peripheral blood (PB) smear in a single institution during 6 years. Schistocytes on 282 PB smears showing previous peripheral schistocytes and hemoglobin ≤10 g/dL were recounted according to ICSH recommendations.

RESULTS

The schistocytes were frequently observed in patients with microangiopathic hemolytic anemia (MAHA), metastatic carcinoma, sepsis, chronic renal failure, preterm infant, and infection. Only two among 34 patients categorized as MAHA were diagnosed as TTP/HUS. Schistocytes were observed with other morphological changes in 169 of 170 cases with schistocyte ≤1% and in 102 of 112 with schistocyte >1%. The median schistocyte percentages of patients with hematologic malignancy, megaloblastic anemia, acute renal failure, and preterm infant were 1.20%, 1.30%, 1.35%, and 1.70%, respectively.

CONCLUSION

Schistocytes were observed above 1% in many diseases other than TTP /HUS. Therefore, it is important to understand that schistocytes could be seen in various diseases, and in these cases, schistocytes were usually detected together with other red blood cell morphologic changes. These data support ICSH recommendation that a schistocyte count should be considered clinically meaningful if schistocytes represent the main morphological abnormality in the PB smear.

Folfox4 as a rescue chemotherapy for gemcitabine-refractory pancreatic cancer

BACKGROUND/AIMS

This phase II study assessed the efficacy and safety of FOLFOX4 as a rescue therapy in patients with gemcitabine-refractory pancreatic cancer.

METHODOLOGY

The study included patients with advanced pancreatic cancer who had failed gemcitabine-based chemotherapy. FOLFOX4 was administered biweekly as follows: oxaliplatin, 85 mg/m² as a 2-hour infusion (day 1); leucovorin, 200 mg/m²/day as a 2-hour infusion (days 1 and 2); 5-fluorouracil, bolus 400 mg/m²/day and 600 mg/m²/day as a 22-hour infusion (days 1 and 2).

RESULTS

Forty-four patients received a total of 264 cycles of chemotherapy. There was 1 complete response (2.2%), 4 partial responses (9.1%), and 13 stable diseases (29.5%). The objective response rate was 11.4% and the tumor stabilization rate was 40.9%. The median time to progression was 9.9 weeks (95%CI: 8.2-11.5) and the median overall survival was 31.1 weeks (95%CI: 24.4-37.9). The common adverse events were hematologic toxicities: grade 3 or 4 neutropenia in 19 patients (43.2%), anemia in 9 patients (20.5%), and thrombocytopenia in 6 patients (13.5%). Grade 3 or 4 neuropathy occurred in 4 patients (9.1%).

CONCLUSIONS

In gemcitabine-refractory pancreatic cancer, FOLFOX4 showed encouraging activity and was generally well-tolerated. However, careful attention needs to be paid to hematologic toxicities.

Clinical implications and risk factors of acute pancreatitis after cardiac valve surgery

PURPOSE

Acute pancreatitis is one of the potentially lethal complications that occurs after cardiac surgery. We tried to identify risk factors for and the prognosis of acute pancreatitis after cardiac valve surgery with cardiopulmonary bypass.

MATERIALS AND METHODS

We retrospectively analyzed a database of consecutive patients who underwent cardiac valve surgery with cardiopulmonary bypass between January 2005 and April 2010 at our institution. Patients were classified as having acute pancreatitis based on serum lipase concentration and clinical symptoms (lipase ≥ 180 U/L or ≥ 60 U/L with relevant symptoms).

RESULTS

Of the 986 patients who underwent cardiac valve surgery with cardiopulmonary bypass, 58 (5.9%) patients developed post-operative pancreatitis. Post-operative hospital stay was significantly longer (29.7 ± 45.6 days vs. 12.4 ± 10.7 days, p = 0.005) and in-hospital mortality rate was higher (15.5% vs. 2.0%, p<0.001) in patients with post-operative pancreatitis than those without. Hypertension, chronic kidney disease, and peri-operative use of norepinephrine were identified as independent risk factors for developing pancreatitis after cardiac valve surgery.

CONCLUSION

We found that acute pancreatitis after cardiac valve surgery requires longer hospitalization and increases the in-hospital mortality rate. Clinicians should be aware that patients could develop pancreatitis after cardiac valve surgery, especially in patients with hypertension and chronic kidney disease treated with norepinephrine.

Clinical features and outcomes of primary hepatic neuroendocrine carcinomas

BACKGROUND AND AIM

Primary hepatic neuroendocrine carcinomas (PHNECs) are extremely rare, with only about 150 cases having been reported in the English-language literature. Because of the rarity of PHNECs, its clinical features and treatment outcomes are not well understood. Here, we report our experiences with PHNECs.

METHODS

We identified patients diagnosed with PHNEC and analyzed their demographics, baseline laboratory data, tumor characteristics, treatment modalities and outcomes.

RESULTS

A total of 218 consecutive patients were identified with pathologically confirmed neuroendocrine carcinoma. Of these, 12 patients were diagnosed with PHNECs; the median age was 66.5 years (range, 37 to 80 years), and seven patients (58.3%) were male. Two patients who each had a single hepatic mass underwent curative surgical resection. One patient who was of inoperable status at the initial diagnosis because of multiple intrahepatic metastases showed a partial response after the ninth round of systemic chemotherapy and then underwent surgical resection. The median overall survival in the 12 patients was 16.5 months (range, 0.7 to 41.7 months). Three patients who underwent surgical treatment are alive without recurrence for 15.2 months, 18.0 months, and 36.9 months, respectively.

CONCLUSIONS

Primary hepatic neuroendocrine carcinoma should be considered as a possible differential diagnosis in the management of hepatic tumors. The liver can be the primary origin of neuroendocrine tumors, and if the tumors are diagnosed as primary hepatic neuroendocrine tumors, surgical resection must be considered for curative treatment.

Radiofrequency ablation combined with transcatheter arterial embolisation in rabbit liver: investigation of the ablation zone according to the time interval between the two therapies

OBJECTIVES

This study was designed to evaluate the extent of the radiofrequency ablation zone in relation to the time interval between transcatheter arterial embolisation (TAE) and radiofrequency ablation (RFA) and, ultimately, to determine the optimal strategy of combining these two therapies for hepatocellular carcinoma.

METHODS

15 rabbits were evenly divided into three groups: Group A was treated with RFA alone; Group B was treated with TAE immediately followed by RFA; and Group C was treated with TAE followed by RFA 5 days later. All animals underwent perfusion CT (PCT) scans immediately after RFA. Serum liver transaminases were measured to evaluate acute liver damage. Animals were euthanised for pathological analysis of ablated tissues 10 days after RFA. Non-parametric analyses were conducted to compare PCT indices, the RFA zone and liver transaminase levels among the three experimental groups.

RESULTS

Group B showed a significantly larger ablation zone than the other two groups. Arterial liver perfusion and hepatic perfusion index represented well the perfusion decrease after TAE on PCT. Although Group B showed the most elevated liver transaminase levels at 1 day post RFA, the enzymes decreased to levels that were not different from the other groups at 10 days post-RFA.

CONCLUSIONS

When combined TAE and RFA therapy is considered, TAE should be followed by RFA as quickly as possible, as it can be performed safely without serious hepatic deterioration, despite the short interval between the two procedures.

Stabilization of carbon in composts and biochars in relation to carbon sequestration and soil fertility

There have been increasing interests in the conversion of organic residues into biochars in order to reduce the rate of decomposition, thereby enhancing carbon (C) sequestration in soils. However energy is required to initiate the pyrolysis process during biochar production which can also lead to the release of greenhouse gasses. Alternative methods can be used to stabilize C in composts and other organic residues without impacting their quality. The objectives of this study include: (i) to compare the rate of decomposition among various organic amendments and (ii) to examine the effect of clay materials on the stabilization of C in organic amendments. The decomposition of a number of organic amendments (composts and biochars) was examined by monitoring the release of carbon-dioxide using respiration experiments. The results indicated that the rate of decomposition as measured by half life (t(1/2)) varied between the organic amendments and was higher in sandy soil than in clay soil. The half life value ranged from 139 days in the sandy soil and 187 days in the clay soil for poultry manure compost to 9989 days for green waste biochar. Addition of clay materials to compost decreased the rate of decomposition, thereby increasing the stabilization of C. The half life value for poultry manure compost increased from 139 days to 620, 806 and 474 days with the addition of goethite, gibbsite and allophane, respectively. The increase in the stabilization of C with the addition of clay materials may be attributed to the immobilization of C, thereby preventing it from microbial decomposition. Stabilization of C in compost using clay materials did not impact negatively the value of composts in improving soil quality as measured by potentially mineralizable nitrogen and microbial biomass carbon in soil.

The time-dependent alteration of anti-diuretic hormone system in hindlimb unloaded rats

It is important to understand the mechanism on the fluid shift and volume regulation occurring in astronauts after spaceflight for future life in space. In the present study, we examined the time-dependent alteration of anti-diuretic hormone (ADH) concentrating on the water reabsorption system in hindlimb unloaded rats. Male Sprague-Dawley rats were hindlimb unloaded for 1 (HU1), 7(HU7), 14 days (HU14) or rested in the ground for 3 days after HU14 (HU14+3). The plasma ADH and angiotensin II level showed peak value at HU7, and the alterations were restored at HU14. However, several serum electrolytes (Na, K, Cl) were not changed regardless of HU period. In the immunohistochemical study, we examined that ADH and c-Fos immunoreactivities (IR) were maximized at HU7 in the paraventricular nucleus (PVN) and supraoptic nucleus (SON). Aquaporin 2 (AQP2) IR also was increased in the renal collecting duct for water re-absorption at HU7 showing a similar pattern with ADH. These results present a series of physiological ADH system alteration following to period of hindlimb unloading stimulus, indicating that ADH system is activated significantly at HU7. In addition, our results suggest that ADH system activation may be involved in anti-diuretic phenomenon in early spaceflight period. Furthermore, it is speculated that ADH system may require 14 days for adaptation to microgravity.

A novel disposable, transnasal esophagoscope: a pilot trial of feasibility, safety, and tolerance

A novel disposable transnasal esophagoscope, the E.G. Scan (IntroMedic Co. Ltd., Seoul, Korea), was developed for the evaluation of esophageal diseases while eliminating the inconvenience associated with sterilization, portability, patient monitoring, complications, and the economic burden of sedation. The feasibility, safety, and tolerability of the first version of the E.G. Scan was evaluated in this pilot study. Nasal esophagoscopy was performed successfully in 46 patients with known or suspected esophageal diseases. At least 50% of the Z-line was visualized by the E.G. Scan in 38 (82.6%) of 46 patients. Abnormalities were identified in 27 patients: erosive esophagitis (n=18), Barrett's esophagus (n=1), esophageal varices (n=7), and esophageal candidiasis (n=1). Nasal pain was absent or mild in most patients, and adverse events were not observed. Further technical improvement of the E.G. Scan would increase the diagnostic usefulness in future clinical practice.

Development of a new dynamic gas flow-control system in the pressure range of 1 Pa-133 Pa

A new flow-control system (FCS-705) has been developed at Korea Research Institute of Standards and Science. The system is intended for calibration of vacuum gauges in the pressure range of 1 Pa-133 Pa by comparison method. This paper describes some basic characteristics of the system including; (1) the design and construction of the system, (2) the generation of stable pressures in the chamber, (3) achieving high upstream pressure limit by installing a short duct in the by-pass pumping line, and (4) investigation of the gas flow regimes within the short duct.

Primary intestinal lymphangiectasia diagnosed by capsule endoscopy and double balloon enteroscopy

Primary intestinal lymphangiectasia (PIL) is a rare disorder characterized by dilated intestinal lymphatics and the development of protein-losing enteropathy. Patients with PIL develop hypoalbuminemia, hypocalcemia, lymphopenia and hypogammaglobulinemia, and present with bilateral lower limb edema, fatigue, abdominal pain and diarrhea. Endoscopy reveals diffusely elongated, circumferential and polypoid mucosae covered with whitish enlarged villi, all of which indicate intestinal lymphangiectasia. Diagnosis is confirmed by characteristic tissue pathology, which includes dilated intestinal lymphatics with diffusely swollen mucosa and enlarged villi. The prevalence of PIL has increased since the introduction of capsule endoscopy. The etiology and prevalence of PIL remain unknown. Some studies have reported that several genes and regulatory molecules for lymphangiogenesis are related to PIL. We report the case of a patient with PIL involving the entire small bowel that was confirmed by capsule endoscopy and double-balloon enteroscopy-guided tissue pathology who carried a deletion on chromosome 4q25. The relationship between this deletion on chromosome 4 and PIL remains to be investigated.

The study of new vacuum pressure measurement technique using ultrasonic acoustic impedance transducers

Ultrasonic sensors of 500 kHz frequency have been used to study the measuring of gas pressure in the range 1.33 × 10(3)-2.026 × 10(5) Pa. From the experimental data it was observed that amplitude of the transmitted ultrasound was dependent on gas pressure. The results confirm that by using appropriate instruments including sensors and electronic devices, pressure of the gas can be successfully measured by measuring the magnitude of the received signal. The proposed method is expected to be applied to develop as new vacuum pressure measurement instrument.

Proteomic analysis of pancreatic juice for the identification of biomarkers of pancreatic cancer

INTRODUCTION

Protein profiles of endoscopically collected pancreatic juice from normal, chronic pancreatitis patients and pancreatic cancer patients were compared to identify diagnostic biomarkers of pancreatic cancer.

METHODS

Secretin was injected intravenously and pancreatic juice was collected via selective cannulation of the pancreatic duct during endoscopic retrograde cholangiopancreatography. Pancreatic juices consisting of three pooled samples for normal control, chronic pancreatitis, and pancreatic cancer patients were compared using two-dimensional gel electrophoresis, and the proteins were subsequently identified using MALDI-TOF-MS.

RESULTS

Thirty-five protein spots were up-regulated twofold in pancreatic cancer compared with the levels in the normal controls, and 85 protein spots were present in pancreatic cancer samples but not in normal controls. After excluding spots that were also expressed in chronic pancreatitis, 26 protein spots that were up-regulated or only expressed in pancreatic cancer samples were identified. Among the identified proteins, we confirmed the expressions of BIG2, PRDX6, and REG1α in pancreatic cancer tissue using immunohistochemistry. ELISA showed that the serum level of REG1α was significantly higher in patients with pancreatic cancer than it was in the normal controls (P = 0.023). With the best cut-off value, the sensitivity and specificity of REG1α to differentiate normal and pancreatic cancer were 82.6 and 81.8%, compared with 69.6 and 100% for CA19-9.

CONCLUSIONS

We have shown that pancreatic juice is a good source of pancreatic cancer tumor markers. Further studies are needed to determine the clinical implications of REG1α and other markers.

Coenzyme Q10 in combination with steroid therapy for treatment of sudden sensorineural hearing loss: a controlled prospective study

OBJECTIVE

To evaluate the therapeutic efficacy of coenzyme Q10 added to systemic steroid in patients with idiopathic sudden sensorineural hearing loss.

DESIGN

A controlled prospective study.

SETTING

Asan medical center, University of Ulsan College of Medicine.

PARTICIPANTS

Between August 2007 and October 2008, the first 60 patients diagnosed with sudden sensorineural hearing loss were managed with systemic steroid treatment for 2 weeks including 5-day hospitalisation. And the second 60 patients were managed with coenzyme Q10 for 2 weeks added to previous management.

MAIN OUTCOME MEASURES

We evaluated auditory function by pure tone audiometry and speech discrimination score. Auditory evaluations were performed before and 3 months after treatment using Siegel's criteria. The degree of improvement in four-tone average hearing and speech discrimination score was calculated from the results before and after treatment.

RESULTS

The total hearing improvement rate after the treatment was 75.0% (90/120 patients) in this study. Although 47 patients (78.3%) of coenzyme Q10 group showed better hearing improvement than 43 patients (71.7%) of control group, there was no significant difference. However, the coenzyme Q10 group showed significantly higher improvement in speech discrimination score.

CONCLUSION

From this study, we suggest that coenzyme Q10 may have beneficial effects in the treatment of sudden sensorineural hearing loss.

Fibroblast growth factor-9 in marsupial testicular development

FGF9 is a member of the fibroblast growth factor (FGF) family and is critical for early testicular development and germ cell survival in the mouse. Fgf9 reinforces the testis determinant Sox9 and antagonizes Wnt4, an ovarian factor. To determine whether FGF9 has a conserved role in the mammalian gonad, we examined its expression in the gonads of a marsupial, the tammar wallaby Macropus eugenii, and compared it to WNT4 expression. Marsupial FGF9 is highly conserved with orthologues from eutherian mammals, including humans. FGF9 protein was detected in both the testis and ovary before sexual differentiation, but it subsequently became sexually dimorphic during the period of testicular differentiation. The protein was specifically enriched in the seminiferous cords of the developing testis in the Sertoli and germ cells. FGF9 mRNA expression was upregulated in the tammar testis at the time of seminiferous cord formation and downregulated in the developing ovary in an opposite profile to that of marsupial WNT4. These observations suggest that FGF9 promotes male fate in the early gonad of marsupials through an antagonistic relationship with WNT4 as it does in eutherian mammals.

Endoscopic papillary balloon dilation for removal of choledocholithiasis: indications, advantages, complications, and long-term follow-up results

Endoscopic papillary balloon dilation (EPBD) is an alternative method of endoscopic sphincterotomy (EST). Although concerns regarding post-procedure pancreatitis have been expressed, EPBD has come to be recognized as an effective and safe method for stone removal in specific cases. To analyze the proper indications, ideal methods, complications, and long-term follow-up results for EPBD, we reviewed articles about EPBD located through a search of the PubMed data base. We analyzed the ballooning methods, indications, results and complications of EPBD among the articles found and compared the results with those of EST. We considered the authors' own clinical experience and knowledge in developing recommendations for EPBD. EPBD showed similar efficacy and safety for the removal of choledocholithiasis to that of EST. Although large or multiple stones were difficult to remove by EPBD, it was safer and easier to apply in patients with coagulopathy or abnormal anatomy. To prevent severe pancreatitis, excessive ballooning and impractical cannulation should be avoided, and precut sphincterotomy or adjuvant prophylaxis should be considered. Due to its preservation of the sphincter of Oddi, EPBD is expected to have fewer long-term complications, such as stone recurrence, cholangitis and cholecystitis. In conclusion, EPBD appears to be safe and effective for the treatment of choledocholithiasis with proper selection of ballooning methods and patients.

Placement of a fully covered self-expandable metal stent in a young patient with chronic pancreatitis

Plastic stent insertion is a treatment option for pancreatic duct stricture with chronic pancreatitis. However, recurrent stricture is a limitation after removing the plastic stent. Self-expandable metal stents have long diameters and patency. A metal stent has become an established management option for pancreatic duct stricture caused by malignancy but its use in benign stricture is still controversial. We introduce a young patient who had chronic pancreatitis and underwent several plastic stent insertions due to recurrent pancreatic duct stricture. His symptoms improved after using a fully covered self-expandable metal covered stent and there was no recurrence found at follow-up at the outpatient department.

Development and validation of a novel prognostic scoring model for ischemic colitis

PURPOSE

This study was conducted to identify prognostic factors affecting the course of ischemic colitis and to develop a prognostic scoring model.

METHODS

We analyzed medical records of consecutive patients with ischemic colitis treated between October 2002 and September 2008 at Severance Hospital, Seoul, Republic of Korea. Patients were excluded if results of endoscopy were unavailable. Patients were classified as having severe ischemic colitis on the basis of outcome (improvement delayed for more than 2 weeks, complications requiring surgery, or death). Univariate analyses and multivariate logistic regression analyses with backward stepwise selection were used to identify clinical, endoscopic, and laboratory variables associated with severe ischemic colitis. A novel prognostic scoring model was derived from the data, with probability of severe ischemic colitis and risk index determined for 8 risk groups based on independent risk factors identified by multivariate analyses. Predictive power was tested by means of 10-fold cross-validation, with area under the receiver operating characteristic curve representing discrimination accuracy.

RESULTS

Analyzable data were available for 153 of 173 consecutive patients. Ischemic colitis was classified as severe in 20 patients. Multivariate analyses showed the following significant independent predictors of severe ischemic colitis: tachycardia (adjusted odds ratio = 4.6; 95% CI, 1.4-14.7), shock within 24 hours after admission (adjusted odds ratio = 6.5; 95% CI, 2.0-21.2), and endoscopic evidence of ulceration (adjusted odds ratio = 9.9; 95% CI, 2.0-48.8). Probability of severe ischemic colitis and risk index were 74 times higher for patients with all 3 risk factors (group 8) than for patients with none (group 1). Internal validation showed the area under the receiver operating characteristic curve to be 0.91 (95% confidence interval, 0.86-0.96).

CONCLUSIONS

Endoscopic findings and instability of vital signs were associated with the disease course of ischemic colitis. A novel scoring model based on presence of tachycardia, shock within 24 hours after admission, and endoscopic evidence of ulceration provides a method of assessing patient prognosis and should be further validated.

A case of embryonal sarcoma of the liver mimicking a hydatid cyst in an adult

An undifferentiated (embryonal) liver sarcoma (ULS) originates from a primitive mesenchymal cell, with a predilection for childhood and very rare occurrence in adults. We report a case of a ULS that was incidentally found in a 53-year-old female. Our case was initially interpreted as a large hydatid cyst, which was later suspected to be a neoplastic lesion because its size was increasing and a solid portion was newly detected after shrinkage of the cyst following drainage. The patient underwent successful right hepatic lobectomy with complete resection, and is currently disease-free without adjuvant therapy. Although it is difficult to diagnose a hepatic cyst as a ULS due to its rare occurrence in adulthood and lack of specific findings, its possibility should be considered, especially when its size is increasing, because early diagnosis and curative resection are necessary for a favorable outcome.

Daily 300 mg dose of linezolid for the treatment of intractable multidrug-resistant and extensively drug-resistant tuberculosis

BACKGROUND

Although previous studies have suggested that linezolid may be effective for treating multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB), the optimal dose of linezolid for intractable MDR/XDR-TB is not clear.

METHODS

Twenty-four patients with intractable MDR/XDR-TB were treated with a daily 300 mg dose of linezolid as part of their anti-TB drug regimen.

RESULTS

The patients were treated with linezolid for a median duration of 359 days [interquartile range (IQR) 268-443 days]. Seventeen (71%) patients received 300 mg of linezolid once daily from the beginning of treatment for a median duration of 289 days (IQR 233-405 days). Of these patients, four developed peripheral neuropathy, one of whom discontinued linezolid. In seven (29%) patients, 600 mg/day linezolid was administered initially for a median duration of 104 days (IQR 26-145 days) followed by 300 mg/day linezolid for a median duration of 348 days (IQR 298-427 days). In five of these seven patients, the reason for changing from 600 to 300 mg/day was due to side effects of 600 mg/day linezolid (peripheral neuropathy in four patients and leucopenia in one patient). After reducing the dose to 300 mg/day, linezolid could be continued in six of the seven patients. Negative sputum conversion was achieved in 22 (92%) patients after a median of 89 days from the start of linezolid treatment (IQR 48-160 days).

CONCLUSIONS

A daily 300 mg dose of linezolid may be useful for increasing the chances of culture conversion in the treatment of patients with intractable MDR/XDR-TB and might have fewer side effects, especially neurotoxicity, compared with a daily 600 mg dose of linezolid therapy. The present results encourage further research into the use of a 300 mg dose of linezolid for MDR/XDR-TB patients.

Coarsening kinetics of a spinodally decomposed vicinal Si(111) surface

The coarsening kinetics of the stepped-and-terrace groove structure formed on a vicinal Si(111) surface was investigated by in-situ synchrotron x-ray scattering. The time evolution of the groove period L at various temperatures below the (1 x 1)-to-(7 x 7) transition falls onto a universal curve when the annealing time is scaled by a scale factor. Distinctive stages of spinodal decomposition, coarsening, and saturation are identified in the evolution of the groove period. L increases following a power law, L approximately t;{n} with n = 1/6 and 0.29 in the initial stage and the late stage of coarsening, respectively. The initial coarsening proceeds via collective motion of step bunches while the late stage is dominated by the diffusion of individual steps.

VDUP1 potentiates Ras-mediated angiogenesis via ROS production in endothelial cells

Vitamin D3 up-regulated protein 1 (VDUP1) is a tumor suppressor of which expression is reduced in a variety of cancer cells, and enforced expression inhibits the tumor cell proliferation. It inhibits the activity of thioredoxin, thus contributing cellular ROS generation. Since ROS is a critical factor for angiogenesis, we investigated the role of VDUP1 in angiogenesis and endothelial proliferation. The expression of VDUP1 was upregulated by overexpression of an oncogene, Ras. Enforced expression of VDUP1 increases ROS production and proliferation of Ras-overexpressing endothelial cells. Overexpression of VDUP1 increases the resistance to the anchorage-dependent cell death and tube formation of the Ras-overexpressing endothelial cell. In addition, the removal of ROS by ROS scavenger attenuates the effect of VDUP1 on tube formation. These results suggest that VDUP1 is involved in Ras-mediated angiogenesis via ROS generation in endothelial cells.

Tension pneumopericardium after removal of pericardiocentesis drainage catheter

This image showed tension pneumopericardium caused by removing the pericardiocentesis catheter, which was inserted to drain malignant pericardial effusion. Tension pneumopericardium is a rare and potentially fatal event. Mortality from tension pneumopericardium can be as high as 50%. Therefore, it is important to suspect and detect early, if the patient complained of dyspnea after removing the pericardiocentesis drainage catheter.

[A case of giant Brunner's gland hyperplasia combined with adenomyomatous hyperplasia]

Brunner's gland hyperplasia is a rare tumor of the duodenum and might also be an unusual cause of gastrointestinal bleeding. In symptomatic patients, treatment requires either surgical resection or endoscopic polypectomy. We report a case of upper gastrointestinal bleeding from a pedunculated Brunner's gland hyperplasia in the duodenal bulb. Endoscopic resection using the detachable snare and hemoclipping was instituted to remove a large pedunculated polyp. The pathologic diagnosis was Brunner's gland hyperplasia with adenomyomatous hyperplasia.

Comfort evaluation of maternity support garments in a wear trial

This study aims to evaluate the wear comfort of eight commercially available maternity support garments. The thermophysiological, sensory/tactile and movement comfort were assessed in a wear trial using a 19-item questionnaire. Fourteen pregnant Chinese women aged 32.3 +/- 4.2 years were recruited from a local obstetric clinic. The results show that the tested garments generally provided greater sensory comfort than thermophysiological comfort. The thermophysiological comfort was mainly influenced by the fibre contents and breathability. Significant linear relationships were found between material appearance and hand feel (r = 0.86, p < 0.001), and between non-itchiness and no red mark (r = 0.78, p < 0.001). Movement comfort was influenced by the garment type and style features. Overall, the soft, good-fit, cotton/elastane maternity brief was perceived as the best product. The findings of comfort needs in pregnant women and the effects of various garment attributes would be helpful for the development of maternity support garment design criteria that are required to satisfy critical ergonomic needs. Low back pain during pregnancy is a common and significant health problem. A maternity support garment is regarded as a convenient and safe device to stabilise the lumbar spine so as to relieve pain. However, patient compliance is likely to be affected by discomfort and inconvenience. The results of this study provide guidance for the optimal design of maternity support clothing.

Lipo-prostaglandin E1 in combination with steroid therapy is effective for treatment of sudden sensorineural hearing loss in Korean patients with Type 2 diabetes

BACKGROUND

Diabetes mellitus is a risk factor for sudden sensorineural hearing loss (SSNHL), possibly as a result of microvascular damage, increased blood viscosity and embolic and thrombotic episodes. Aim To perform a prospective, randomized clinical trial to determine the therapeutic effect of lipo-prostaglandin E(1) (lipo-PGE(1)) on SSNHL in Korean patients with Type 2 diabetes.

METHODS

The study group consisted of 270 consecutive Korean patients (130 male, 140 female) in whom SSNHL was diagnosed. Patients were classified as diabetic or non-diabetic by the new American Diabetes Association criteria. With the approval of the institute ethics committee, patients were randomly assigned to treatment with of 10 microg lipo-PGE(1) (lipo-PGE(1) group) given as a continuous infusion over 5 days, or saline (placebo group). In addition, all patients studied were treated with 48 mg methylprednisolone for 5 days.

RESULTS

The overall recovery rates after treatment were 51.5% in diabetic and 64.2% in non-diabetic patients. In diabetic patients, there was a significantly higher rate of hearing improvement in the lipo-PGE(1) group (64.7%) compared with the placebo group (37.5%), whereas, in non-diabetic patients, there was no significant difference in rate of hearing improvement between the lipo-PGE(1) group (70.3%) and the placebo group (58.3%).

CONCLUSION

Lipo-PGE(1) may have beneficial effects in the treatment of SSNHL in Korean patients with Type 2 diabetes.

Immunosensor with a controlled orientation of antibodies by using NeutrAvidin–protein A complex at immunoaffinity layer

The orientation of antibody was controlled by using NeutrAvidin-protein A complex on the gold surface of SPR biosensor. The surface density of receptor antibody (anti-hIgG) was compared by treatment of receptor antibody to the layer of avidin, NeutrAvidin, protein A, NeutrAvidin-protein A complex and bare gold surface of SPR biosensor. The ligand antibody (hIgG) was injected to each IA layer and the binding ratio of ligand antibody per unit receptor was estimated as a parameter of orientation control. The NeutrAvidin-protein A complex on gold surface of SPR biosensor showed the highest surface density of receptor antibody as well as the binding ratio of ligand antibody per receptor antibody. The NeutrAvidin-protein A complex was also prepared on biotin-labelled SAM, and the binding ratio of ligand per receptor was found to be significantly improved in comparison to the IA layer prepared by chemical coupling of receptor antibody to the SAM layer. The NeutrAvidin-protein A complex which showed the highest efficiency for the binding of ligand antibodies, was applied for the detection of a cancer marker called CEA. By using NeutrAvidin-protein A complex and sandwich assay for signal amplification, sensitivity was improved to be 1.5-fold higher than bare gold surface and the detection of CEA with the detection limit of 30 ng/ml was achieved.

Sequential analysis of multiple analytes using a surface plasmon resonance (SPR) biosensor

A sequential analysis method for the analysis of two analytes was developed using a surface plasmon resonance (SPR) biosensor. A sample with both analytes was introduced into the single sensing region and then each analyte was analyzed sequentially. Two detection models were devised for the samples with the following composition: (1) one target analyte resulting in a sensor response without any label and the other analyte with only additional label, (2) both target analytes requiring additional labels for detection. A standard curve for each model was prepared and applied for sequential analysis of anti-bovine serum albumin (anti-BSA) antibodies and horseradish peroxidase (HRP). The errors of the sequential analysis of Models 1 and 2 were found to be less than 6%, and this method was therefore acceptable for application. No cross-reaction arising from non-specific binding among the participating antigens and antibodies was shown to occur in Models 1 and 2. For optimization of the analyte binding capacity of immunoaffinity (IA), the concentration ratio of the molecular recognition element at the immobilization step was adjusted. Subsequently, from the measurement of the maximum sensor response (R(max)), optimization of the analyte binding capacity could be made. Using Model 2, the feasibility of sequential analysis was demonstrated by detecting levels of human chorionic gonadotropin (hCG) and human albumin (hA) in healthy human urine, since both proteins are known to be related to abortion and preterm delivery during early pregnancy.

New immobilization method for immunoaffinity biosensors by using thiolated proteins

A new immobilization method for immunoaffinity (IA) biosensors that ensures the high surface density and the stability of the IA layer was developed. For the immobilization of biomolecules, the molecular recognition protein was first thiolated by covalent conjugation of mercaptopropionic acid, and then the thiolated protein was attached on the gold surface of the transducer. In this work, horseradish peroxidase (HRP) and its antibody were used as a model antigen-antibody, and the following properties of the IA layer prepared by thiolated protein were estimated: (i) biological integrity of HRP after the immobilization process by using activity assay, (ii) charge transfer resistance by immobilization, (iii) mass loading by the surface plasmon resonance (SPR) biosensor, (iv) number of binding sites, and (v) feasibility test for the measurement of capacitive change by the antigen-antibody interaction. Based on these parameters, the immobilization method by using thiolated protein was determined to be feasible for application to IA biosensors.

Kinetic roughening of ion-sputtered Pd(001) surface: beyond the Kuramoto-Sivashinsky model

We investigate the kinetic roughening of Ar+ ion-sputtered Pd(001) surface both experimentally and theoretically. In situ real-time x-ray reflectivity and in situ scanning tunneling microscopy show that nanoscale adatom islands form and grow with increasing sputter time t. Surface roughness W(t) and lateral correlation length xi(t) follow the scaling laws W(t) approximately t(beta) and xi(t) approximately t(1/z) with the exponents beta approximately 0.20 and 1/z approximately 0.20, for an ion beam energy epsilon=0.5 keV, which is inconsistent with the prediction of the Kuramoto-Sivashinsky (KS) model. We thereby extend the KS model by applying the coarse-grained continuum approach of the Sigmund theory to the order of O(inverted Delta(4),h(2)), where h is the surface height, and derive a new term of the form inverted Delta(2)(inverted Delta h)(2) which plays a decisive role in describing the observed morphological evolution of the sputtered surface.

Systemic-to-pulmonary venous shunt in superior vena cava obstruction: depiction on computed tomography venography

PURPOSE

To describe computed tomography (CT) venographic appearances of systemic-to-pulmonary venous shunts with CT venography and three-dimensional reconstruction images from patients with superior vena cava obstruction.

MATERIAL AND METHODS

From January 1994 to April 2002, CT venography was performed in 45 patients with superior vena cava obstruction using a single-detector helical CT scanner (n=38) and four-detector row CT scanner (n=7). Analysis of CT scan data included the cause and degree of venous obstruction, the presence of pleural thickening and enhancement, and the attenuation of pulmonary veins. The causative factor for systemic-to-pulmonary venous shunt was evaluated using the Fisher exact test.

RESULTS

Systemic-to-pulmonary venous shunts were observed in four patients (9%) who had high-attenuated pulmonary veins and pleural enhancement on CT venography. Pleural thickening (P=0.01) and a history of pulmonary tuberculosis (P=0.034) are statistically significant risk factors.

CONCLUSION

CT venography showed strong pleural enhancement and high-attenuated pulmonary veins indicating systemic-to-pulmonary venous shunts. Radiologists should study the earlier enhancement of pulmonary veins in patients with superior vena cava obstruction.