Dermatologist-level classification of malignant lip diseases using a deep convolutional neural network

BACKGROUND

Deep convolutional neural networks (DCNNs) can classify skin diseases at a level equivalent to a dermatologist, but their performance in specific areas requires further research.

OBJECTIVE

To evaluate the performance of a trained DCNN-based algorithm in classifying benign and malignant lip diseases.

METHODS

A training set of 1629 images (743 malignant, 886 benign) was used with Inception-Resnet-V2. Performance was evaluated using another set of 344 images and 281 images from other hospitals. Classifications by 44 participants (six board-certified dermatologists, 12 dermatology residents, nine medical doctors not specialized in dermatology and 17 medical students) were used for comparison.

RESULTS

The outcomes based on the area under curve, sensitivity and specificity were 0·827 [95% confidence interval (CI) 0·782-0·873], 0·755 (95% CI 0·673-0·827) and 0·803 (95% CI 0·752-0·855), respectively, for the set of 344 images; and 0·774 (95% CI 0·699-0·849), 0·702 (95% CI 0·579-0·808) and 0·759 (95% CI 0·701-0·813), respectively, for the set of 281 images. The DCNN was equivalent to the dermatologists and superior to the nondermatologists in classifying malignancy. After referencing the DCNN result, the mean ± SD Youden index increased significantly for nondermatologists, from 0·201 ± 0·156 to 0·322 ± 0·141 (P < 0·001).

CONCLUSIONS

DCNNs can classify lip diseases at a level similar to dermatologists. This will help unskilled physicians discriminate between benign and malignant lip diseases. What's already known about this topic? Deep convolutional neural networks (DCNNs) can classify malignant and benign skin diseases at a level equivalent to dermatologists. The lips are a unique feature in terms of histology and morphology. Previous studies of DCNNs have not investigated tumours on specific locations. What does this study add? This study shows that DCNNs can distinguish rare malignant and benign lip disorders at the same rate as dermatologists. DCNNs can help nondermatologists to distinguish malignant lip diseases. What are the clinical implications of this work? DCNNs can distinguish malignant and benign skin diseases even at specific locations such as the lips, as well as board-certified dermatologists. Malignant lip diseases are rare and difficult for less trained doctors to differentiate them from benign lesions. This study shows that in dermatology, DCNN can help improve decision-making processes for rare skin diseases in specific areas of the body.

Characterization of focal liver lesions using the stretched exponential model: comparison with monoexponential and biexponential diffusion-weighted magnetic resonance imaging

OBJECTIVE

To compare the stretched exponential model of diffusion-weighted imaging (DWI) with monoexponential and biexponential models in terms of the ability to characterize focal liver lesions (FLLs).

METHODS

This retrospective study included 180 patients with FLLs who underwent magnetic resonance imaging including DWI with nine b values at 3.0 T. The distributed diffusion coefficient (DDC) and intravoxel diffusion heterogeneity index (α) from a stretched exponential model; true diffusion coefficient (D_t), pseudo-diffusion coefficient (D_p), and perfusion fraction (f) from a biexponential model; and apparent diffusion coefficient (ADC) were calculated for each lesion. Diagnostic performances of the parameters were assessed through receiver operating characteristic (ROC) analysis. For 20 patients with treated hepatic metastases, the correlation between the DWI parameters and the percentage of tumor necrosis on pathology was evaluated using the Spearman correlation coefficient.

RESULTS

DDC had the highest area under the ROC curve (AUC, 0.905) for differentiating malignant from benign lesions, followed by D_t (0.903) and ADC (0.866), without significant differences among them (DDC vs. D_t, p = 0.946; DDC vs. ADC, p = 0.157). For distinguishing hypovascular from hypervascular lesions, and hepatocellular carcinoma from metastasis, f  had a significantly higher AUC than the other DWI parameters (p < 0.05). The α had the strongest correlation with the degree of tumor necrosis (ρ = 0.655, p = 0.002).

CONCLUSION

The DDC from stretched exponential model of DWI demonstrated excellent diagnostic performance for differentiating malignant from benign FLLs. The α is promising for evaluating the degree of necrosis in treated metastases.

KEY POINTS

• The stretched exponential DWI model is valuable for characterizing focal liver lesions. • The DDC from stretched exponential model shows excellent performance for differentiating malignant from benign focal liver lesions. • The α from stretched exponential model is promising for evaluating the degree of necrosis in hepatic metastases after chemotherapy.

Combined effects of diabetes and low household income on mortality: a 12-year follow-up study of 505 677 Korean adults

AIM

To examine the effects of diabetes, low income and their combination on mortality in the Korean population.

METHODS

We analysed a total of 505 677 people (53.9% male) aged 40-79 years old from the National Health Insurance Service-National Health Screening (NHIS-HEALS) cohort. Ten levels of household income were used as indicators of economic status. Diabetes was defined as elevated fasting blood glucose (≥ 6.9 mmol/l) and/or use of glucose-lowering drugs or insulin. Covariates of age, sex, BMI, smoking and Charlson Comorbidity Index were determined at baseline. Outcomes were total and cause-specific mortality over 12 years. Cox's proportional hazard regression models were used to estimate hazard ratios (HRs) for mortality according to the presence of diabetes, household income and their combination.

RESULTS

Lower household income was associated with higher mortality from all causes, cardiovascular disease, cancer and non-cancer non-cardiovascular causes. Excessive mortality due to low incomes was observed in both people with and without diabetes. In men, the adjusted HR [95% confidence interval (CI)] of mortality was 1.38 (1.34 to 1.42) for low-income only, 1.48 (1.42 to 1.55) for diabetes only and 1.95 (1.86 to 2.05) for diabetes and low-income combined, relative to the normal glucose and high income group. Corresponding HR (95% CI) in women were 1.19 (1.14 to 1.24), 1.54 (1.44 to 1.64) and 1.87 (1.75 to 2.01), respectively.

CONCLUSION

Both low household income and the presence of diabetes independently increase the risk of mortality, but their combined effects on mortality may be different between men and women.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).

Genomic and Proteomic Evidences for Exopolysaccharide Biosynthesis in Sphingobium chungbukense DJ77

Sphingobium chungbukense DJ77 is a Gram-negative bacterium has metabolic capability of producing exopolysaccharide (EPS) as a potential reducing and stabilizing agent for metallic nanoparticle synthesis. In this study, we investigated the genomic and proteomic analysis to verify metabolic pathway and involved genes and enzymes related to EPS biosynthesis in S. chungbukense DJ77. End-sequencing results of randomly selected fosmid library, which were prepared from high molecular weight DNA of S. chungbukense DJ77, showed identity to sequences from genes related the EPS biosynthesis pathways in several bacteria. We also observed that proteomic responses in S. chungbukense DJ77 by heterogeneously expressing gelA and gelN involved in gellan biosynthesis in Sphingomonas elodea. Comparative two-dimensional gel electrophoresis revealed that both GelA and GelN altered internal expression levels of proteins involved in EPS biosynthesis in S. chungbukense DJ77. The results might provide the genomic and proteomic evidences for presence of EPS biosynthesis pathways in S. chungbukense DJ77.

Cardiovascular events associated with second-line anti-diabetes treatments: analysis of real-world Korean data

AIM

To compare the risks of cardiovascular disease (CVD) and all-cause mortality associated with sulfonylurea (SU), dipeptidyl peptidase-4 inhibitor (DPP4i) and thiazolidinedione (TZD) as add-on medications to metformin (MET) therapy in people with Type 2 diabetes.

METHODS

We identified 40 263 individuals who used SU (n = 11 582), DPP4i (n = 26 623) or TZD (n = 2058) in addition to MET between January 2013 and June 2015 from the database of the Korean National Health Insurance, the single-payer healthcare system in South Korea. Cox proportional hazard models were used to estimate hazard ratios for major CVD event (coronary artery disease, heart failure, stroke or transient ischaemic attack) development and all-cause mortality by second-line anti-diabetes medication type. Age, sex, duration of MET monotherapy, calendar year and comorbid conditions were adjusted as potential confounders.

RESULTS

The observed numbers of CVD events (total observed person-time) were 485 (18 778 person-years) for MET + SU, 744 (40 374 person-years) for MET + DPP4i and 60 (3014 person-years) for MET + TZD users. Compared with MET + SU users, the fully adjusted hazard ratios for CVD events were 0.79 [95% confidence interval (CI): 0.71-0.89] for MET + DPP4i users and 0.85 (95% CI: 0.65-1.11) for MET + TZD users. The corresponding hazard ratios for all-cause mortality were 0.84 (95% CI: 0.66-1.07) for MET + DPP4i users and 0.67 (95% CI: 0.35-1.28) for MET + TZD users.

CONCLUSION

Analysis of Korea National Health Insurance database showed that MET + DPP4i treatment for diabetes had a lower CVD risk than MET + SU treatment.

Seasonally related effects on natural organic matter characteristics from source to tap in Korea

In this study, natural organic matter (NOM) characteristics were investigated over three years of monthly monitoring to determine the effect of seasonal variations on NOM levels from source to tap. Liquid chromatography with organic carbon detection (LC-OCD) was used to determine NOM characteristics and the level of reduction of biodegradable dissolved organic carbon (BDOC). The average dissolved organic matter concentration in the source water (Lake Paldang, Korea) was not significantly different between summer and winter. However, the distribution of NOM components, such as biopolymers, building blocks, low molecular weight (MW) neutrals and acids, identified by LC-OCD, varied seasonally. While high MW NOM was preferentially removed by coagulation/sedimentation/rapid sand filtration (CSR), no seasonal effects were observed on the removal of high MW NOM. CSR and biological activated carbon (BAC) filtration showed a better efficiency of BDOC removal in winter and summer, respectively. High concentrations of chlorine used in the treatment plants in summer resulted in 10% higher DOC concentrations during disinfection. Overall NOM removal efficiencies from source to tap were 45% and 35% for summer and winter, respectively. Principal component analysis also indicated that seasonal variations (principal component 1) showed the strongest positive correlation with the overall performance of water treatment. The long-term monitoring of drinking water treatment processes showed that seasonal variations were important factors affecting NOM characteristics during water treatment.

Anatomical relationship of maxillary posterior teeth with the sinus floor and buccal cortex

This study aimed to evaluate the possibility of root fenestration or oroantral communication by evaluating the distance from root apex to the sinus floor and buccal cortex in maxillary posterior teeth using cone-beam computed tomography (CBCT) images. The study included 2182 roots of the maxillary posterior teeth from 219 patients after reviewing CBCT images of 462 patients according to the location of roots by two endodontists. The distances from each root apex to the maxillary sinus floor and buccal and palatal cortices were evaluated according to sex and age, and the mean values were compared by one-way analysis of variance and Mann-Whitney U-test. The distance between root apex and maxillary sinus floor was the greatest in maxillary first premolars and shortest in the mesio-buccal roots of maxillary second molars. The distances from root apex to the buccal and palatal cortical bones were significantly greater in male patients than those in female patients (P < 0·05). The palatal roots of maxillary first molars exhibited the highest incidence as well as the greatest mean length (1·96 mm) of protrusion into the maxillary sinus. The distance from root apex to the sinus floor was found to increase with age, except in case of maxillary second premolars. Understanding the relationship of maxillary posterior teeth with the sinus floor and buccal cortex could provide clinicians valuable information to help reduce iatrogenic damage.

Theileria buffeli infections in grazing cattle in the Republic of Korea

Theileria infections are encountered worldwide, occasionally resulting in serious economic losses for the livestock industry. This study is an epidemiological survey of Theileria infections in Korean indigenous cattle populations in the Republic of Korea (ROK). Blood samples were collected from 100 cattle in April (n=50) (prior to pastureland grazing), and again four months later, in August (n=50) (half of the cattle put out for grazing and the other half kept in housing). All samples were tested for the presence of Theileria infection based on PCR amplification of the small subunit of ribosomal RNA gene. Twenty-two samples across the whole study were verified as positive for Theileria infection by PCR methods. In August, Theileria infection was markedly increased in grazing cattle (16/25 animals, 64%) compared with indoor cattle (4/25 animals, 16%); affected animals exhibited no clinical signs of infection. The red blood cell, hematocrit, and hemoglobin values were significantly lower in Theileriapositive cattle than in Theileria-negative cattle. Phylogenetic analysis demonstrated that the isolates from this study belonged to the T. buffeli species, and were significantly related to Types A, B, C, and E, and were distinct from T. buffeli Type D, which is known to be more pathogenic. These findings indicate that T. buffeli identified in Korean indigenous cattle have a low-to-mild pathogenicity. These results suggest that the T. buffeli infection is relatively higher in the ROK, and the infection rate may increase following grazing. Taken together, T. buffeli infection may not only be seasonally correlated, but also may be affected by management practices such as pastureland grazing.

Detecting and Discriminating Shigella sonnei Using an Aptamer-Based Fluorescent Biosensor Platform

In this paper, a Whole-Bacteria SELEX (WB-SELEX) strategy was adopted to isolate specific aptamers against Shigella sonnei. Real-time PCR amplification and post-SELEX experiment revealed that the selected aptmers possessed a high binding affinity and specificity for S. sonnei. Of the 21 aptamers tested, the C(t) values of the SS-3 and SS-4 aptamers (Ct = 13.89 and Ct = 12.23, respectively) had the lowest value compared to other aptamer candidates. The SS-3 and SS-4 aptamers also displayed a binding affinity (K_D) of 39.32 ± 5.02 nM and 15.89 ± 1.77 nM, respectively. An aptamer-based fluorescent biosensor assay was designed to detect and discriminate S. sonnei cells using a sandwich complex pair of SS-3 and SS-4. The detection of S. sonnei by the aptamer based fluorescent biosensor platform consisted of three elements: (1) 5’amine-SS-4 modification in a 96-well type microtiter plate surface (N-oxysuccinimide, NOS) as capture probes; (2) the incubation with S. sonnei and test microbes in functionalized 96 assay wells in parallel; (3) the readout of fluorescent activity using a Cy5-labeled SS-3 aptamer as the detector. Our platform showed a significant ability to detect and discriminate S. sonnei from other enteric species such as E. coli, Salmonella typhimurium and other Shigella species (S. flexneri, S. boydii). In this study, we demonstrated the feasibility of an aptamer sensor platform to detect S. sonnei in a variety of foods and pave the way for its use in diagnosing shigellosis through multiple, portable designs.

First-Line Use of Core Needle Biopsy for High-Yield Preliminary Diagnosis of Thyroid Nodules

BACKGROUND AND PURPOSE

Although core needle biopsy was introduced as a diagnostic alternative to fine-needle aspiration, the utility and safety of core needle biopsy for thyroid nodules in a large population has yet to be studied comprehensively. We evaluate core needle biopsy yields on a large-scale basis to investigate its potential in the preliminary diagnosis of thyroid nodules.

MATERIALS AND METHODS

Between March 2005 and December 2013, 2448 initially detected thyroid nodules from 2120 consecutive patients who underwent core needle biopsy were retrospectively evaluated. Of these, 72 thyroid nodules from 63 patients were excluded due to prior fine-needle aspiration attempts. The inconclusive and conclusive result rates, diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and unnecessary surgery rate of core needle biopsy were evaluated.

RESULTS

With core needle biopsy as the first-line method, the inconclusive result rate was 11.9% (283/2376) and the conclusive result rate was 88.1% (2093/2376). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of core needle biopsy for the diagnosis of malignancy were 96.7% (1160/1200), 89.7% (347/387), 100% (813/813), 100% (347/347), and 95.3% (813/853), respectively. There were no major complications and 12 minor complications.

CONCLUSIONS

We have demonstrated that first-line use of core needle biopsy may well improve diagnostic accuracy in thyroid nodules, reducing inconclusive or false-negative results and unnecessary operations. Such benefits underscore the promising role of core needle biopsy in managing thyroid nodules and optimizing related surgical decision-making.

Effects of Anesthetic Agent Propofol on Postoperative Sex Hormone Levels

Introduction: Several studies have found anesthetic agents including propofol in ovarian follicular fluid. However, little is known about the effect of anesthetic agents on ovarian function. We aimed to investigate whether there were differences in the postoperative levels of sex hormones when propofol was used as the anesthetic agent. Methods: A retrospective review was done of 80 patients who underwent ovarian surgery, with 72 infertile women serving as controls. Patients were included in the study if their serum estradiol (E2) and follicle stimulating hormone (FSH) levels were measured during their first postoperative menstrual cycle. Results: Patients were grouped according to the use or non-use of propofol as follows: propofol group (n = 39) and non-propofol group (n = 41). The control group did not undergo surgery. Postoperative E2 levels did not differ between the three groups, but FSH levels were significantly higher in the patients who had undergone surgery compared to controls (p < 0.05). Post-hoc analysis of E2 and FSH levels in the propofol and non-propofol groups did not show any significant differences. Conclusions: The use of propofol did not result in any differences compared to other anesthetic agents in terms of postoperative sex hormone levels after gynecologic surgery. The type of anesthetic agent does not seem to affect the postoperative levels of female sex hormones.

In vitro Screening for Antioxidant, Antimicrobial, and Antidiabetic Properties of Some Korean Native Plants on Mt. Halla, Jeju Island

In this study, Prunus padus, Lonicera caerulea, Berberis amurensis, and Ribes maximowiczianum, which are mainly distributed on Mt. Halla, Jeju Island, have been investigated for their antioxidant, antimicrobial, and antidiabetic activities. The methanol extracts of R. maximowiczianum leaves and P. padus branches exhibited significant and dose-dependent antioxidant activity including electron-donation ability and reducing power. To analyze the antimicrobial activity, each extract was tested by a serial two-fold dilution method against five selected gram-positive bacteria and four gram-negative bacteria, and this suggested that P. padus branches possessed the maximum antimicrobial activity against most of the gram-positive bacteria tested. In addition, the methanol extracts of P. padus branches exhibited the highest α-glucosidase inhibitory activity with an IC₅₀ value of 1.0±0.1 μg/ml, indicating that P. padus is a promising source as a herbal medicine.

Development and clinical validation of a novel photography-based skin pigmentation evaluation system: a comparison with the calculated consensus of dermatologists

OBJECTIVE

Various cosmetics, medicines, and light and laser treatments have been increasingly developed to improve pigmentary skin alterations such as melasma, actinic lentigo and dyschromia. To determine the efficacy of these modalities in view of the changes in pigmentation, an objective and reliable device that has a comparable performance to that of physicians is required. We developed a novel photography-based skin pigmentation evaluation system and validated its accuracy and reliability with a newly proposed method.

METHODS

A novel photography-based system was developed that integrates a consistent photography setting and image processing diagnostic algorithms. To automatically detect areas of pigmentation, the diagnostic algorithms were applied to photographs, which were obtained from 31 female patients. To validate its performance in comparison with the physicians' evaluation, five dermatologists independently evaluated the area of pigmentation. The clinical consensus area of pigmentation (CCAP) was calculated based on the consensus of five dermatologists' to exclude subjectivity or bias, and it was compared with the pigmentation area determined by the system.

RESULTS

Forty-four photographs with pigmented areas were evaluated by the system and the physicians. In contrast to the individual physician assessments, CCAP reduced the error that occurred due to subjectivity and bias, particularly for areas with indistinct pigmentation, and it was set as the gold standard. The results from the system showed a mean accuracy of 92.1% and a standard deviation of 4.6% in comparison with CCAP.

CONCLUSION

This pigmentation evaluation system can reproduce the physicians' consensus, suggesting that this system can support the dermatologists' objective evaluation of pigmentation.

Performance of HbA1c for the prediction of diabetes in a rural community in Korea

AIM

To investigate the performance of HbA1c in predicting incident diabetes among Korean adults with normal fasting glucose and impaired fasting glucose levels.

METHODS

This study used data from the Korean Genome Epidemiology Study-Kangwha Study. A prospective analysis was carried out on 2079 people (820 men and 1259 women) who completed follow-up examinations up until 2013. Diabetes was defined as fasting blood glucose level ≥ 7.0 mmol/l, HbA1c level ≥ 48 mmol/mol (6.5%), or current treatment for diabetes. Areas under the receiver-operating characteristic curves were used to assess the different performances of HbA1c , glucose and insulin in predicting diabetes.

RESULTS

The median follow-up time was 3.97 years, during which 7.7% of men and 6.3% of women developed incident diabetes. The areas under the receiver-operating curves (95% CI) for diabetes prediction were 0.740 (0.692-0.787) for HbA1c , 0.716 (0.667-0.764) for glucose and 0.598 (0.549-0.648) for insulin. HbA1c showed better predictive power in people with impaired fasting glucose (area under the curve 0.753, 95% CI 0.685-0.821) than in those with normal glucose (area under the curve 0.648, 95% CI 0.577-0.719). An HbA1c threshold of 40 mmol/mol (5.8%) was found to have the highest predictive value for diabetes, with a relative risk of 6.30 (95% CI 3.49-11.35) in men and 3.52 (95% CI 2.06-6.03) in women after adjusting for age, waist circumference, triglycerides, hypertension, family history of diabetes, smoking, alcohol intake, exercise and baseline glucose level.

CONCLUSIONS

HbA1c can be used to identify people at high risk for the development of diabetes, especially in those with impaired fasting glucose levels.

Gastrointestinal stromal tumours (GISTs) with a thousand faces: atypical manifestations and causes of misdiagnosis on imaging

Gastrointestinal stromal tumours (GISTs) can lead to emergency situations, such as gastrointestinal bleeding, intestinal obstruction, and tumoural rupture with haemoperitoneum or peritonitis. In addition, if a GIST grows exophytically to a large size, it is often misdiagnosed as a tumour arising from adjacent organs. Sometimes, the atypical appearance of GISTs on imaging causes diagnostic confusion. In this article, we illustrate a variety of GISTs with atypical presentations and also discuss the important diagnostic clues for differentiating GISTs from other lesions.

Gallbladder carcinoma: causes of misdiagnosis at CT

Gallbladder carcinomas can present with varied imaging features on computed tomography. The three major imaging features include (1) focal or diffuse wall thickening with or without irregularity of the gallbladder; (2) polypoidal intraluminal mass; and (3) large mass obscuring and replacing the gallbladder, often extending to the liver. Patterns of wall thickening or polypoid growth are often confused with various benign gallbladder diseases due to overlap of imaging findings. Moreover, gallbladder carcinomas that coexist with benign gallbladder diseases make accurate preoperative diagnosis more difficult. Recently, high-resolution ultrasound (HRUS) has been regarded as a problem-solving tool for gallbladder diseases. In this article, we will illustrate various imaging presentations of gallbladder cancer, along with imaging pitfalls and recently updated HRUS findings.

The Effect of the Pedicle-Facet Angle on Degenerative Cervical Spondylolisthesis

Objective

To measure the orientation of the facet joints of cervical spine (C-spine) segments in the sagittal plane, known as the pedicle-facet (P-F) angle, and to use these measurements to evaluate the relationship between the P-F angle and the amount of vertebral anterolisthesis in patients with degenerative cervical spondylolisthesis (DCS).

Methods

A retrospective case-control study was performed including 30 age- and sex-matched patients with DCS and 30 control participants. Anterior-posterior and lateral view radiographs of the C-spine were obtained in a standing position. The P-F angle at all cervical levels and the amount of anterolisthesis at C4-5 were measured from lateral view plain radiographs.

Results

The P-F angles at C4-5 were 141.14±7.14° for the DCS group and 130.53±13.50° (p=0.012) for the control group, and at C5-6 were 137.46±8.53° for the DCS group and 128.53±16.01° for the control group (p=0.001). The mean P-F angle at C4-5 did not correlate with the amount of anterolisthesis (p=0.483). The amount of anterior slippage did correlate with age (p<0.001).

Conclusion

The P-F angle was intrinsically higher at C4-5, compared to C5-6, in both the DCS and control groups, which might explain the increased likelihood for anterolisthesis of C4. Higher P-F angles in the DCS group may be a predisposing factor to slippage. The P-F angle may interact with age to increase incidence of anterolisthesis with increasing age.

The Effect of Different Pillow Heights on the Parameters of Cervicothoracic Spine Segments

Objective

To investigate the effect of different pillow heights on the slope of the cervicothoracic spine segments.

Methods

A prospective analysis of data from 16 asymptomatic adults (aged 20 to 30 years) was carried out. Exclusion criteria were history of injury or accident to the cervicothoracic spine, cervicothoracic spine surgery, or treatment for neck symptoms. We used three different pillow heights: flat (0 cm), 10-cm, and 20-cm pillows. Cervical sagittal parameters, measured with radiography, included; C2-7 Cobb's angle, T1 slope (T1S), thoracic inlet angle (TIA), and neck tilt (NT). Statistical analyses were performed using Spearman correlation coefficients.

Results

As the height of the pillow increased, the T1S & C2-7 Cobb's angle increased while the NT values tended to decrease. The TIA values, however, remained constant. Additionally, there was a statistically significant sex difference in T1S with the 0-cm pillow (p=0.01), and in NT with the 20-cm pillow (p=0.01).

Conclusion

From the data obtained in this study, we recommend that the most suitable pillow height is 10 cm, considering the normal cervical lordosis.

Ruptured Total Intrameatal Anterior Inferior Cerebellar Artery Aneurysm

Among the distal anterior inferior cerebellar artery (AICA) aneurysms, a unique aneurysm at the meatal loop inside the internal auditory meatus is extremely rare. The authors report a case of surgically treated total intrameatal AICA aneurysm. A 62-year-old female patient presenting with sudden bursting headache and neck pain was transferred to our department. Computed tomography and digital subtraction angiography showed subarachnoid hemorrhage at the basal, prepontine cistern and an aneurysm of the distal anterior inferior cerebellar artery inside the internal auditory meatus. Surgery was performed by retrosigmoid craniotomy with unroofing of the internal auditory meatus. The aneurysm was identified between the seventh and eighth cranial nerve in the meatus and was removed from the canal and clipped with a small straight Sugita clip. After operation the patient experienced transient facial paresis and tinnitus but improved during follow up.

Usefulness of the ratio of orbital fat to total orbit area in mild-to-moderate thyroid-associated ophthalmopathy

OBJECTIVE

To identify a useful predictor of thyroid-associated ophthalmopathy (TAO) from orbital CT images; to evaluate the orbital fat and extraocular muscle area ratio as a CT-derived measure; and to investigate the correlations between this ratio and the clinical manifestations in mild-to-moderate TAO.

METHODS

Between January 2012 and March 2013, 44 patients with TAO and 23 controls were studied prospectively. All of the patients underwent ophthalmic examinations, including clinical activity score, exophthalmometry, clinical photographs, alternate prism and cover test, duction and version test, Hess screen test, binocular single vision test, thyroid function tests and orbital CT. The cross-sectional areas of the four rectus muscles, superior oblique muscle, optic nerve and total orbit area were calculated in the coronal view 6 mm posterior from the posterior pole of globe.

RESULTS

The cross-sectional area measured on orbital CT showed increased orbital fat in patients with TAO and an increased orbital fat to total orbit area ratio (fat/orbit) in TAO with retraction and proptosis. There were significant correlations between fat/orbit and margin reflex distance 1 (p = 0.022), margin reflex distance 2 (p = 0.013) and the exophthalmometric value (p = 0.007).

CONCLUSION

The orbital fat to total orbit area ratio (fat/orbit) is a useful diagnostic index in mild-to-moderate TAO.

ADVANCES IN KNOWLEDGE

The orbital CT offers a useful diagnostic index in TAO.

Genome-wide Association Study for Warner-Bratzler Shear Force and Sensory Traits in Hanwoo (Korean Cattle)

Significant SNPs associated with Warner-Bratzler (WB) shear force and sensory traits were confirmed for Hanwoo beef (Korean cattle). A Bonferroni-corrected genome-wide significant association (p<1.3×10⁻⁶) was detected with only one single nucleotide polymorphism (SNP) on chromosome 5 for WB shear force. A slightly higher number of SNPs was significantly (p<0.001) associated with WB shear force than with other sensory traits. Further, 50, 25, 29, and 34 SNPs were significantly associated with WB shear force, tenderness, juiciness, and flavor likeness, respectively. The SNPs between p = 0.001 and p = 0.0001 thresholds explained 3% to 9% of the phenotypic variance, while the most significant SNPs accounted for 7% to 12% of the phenotypic variance. In conclusion, because WB shear force and sensory evaluation were moderately affected by a few loci and minimally affected by other loci, further studies are required by using a large sample size and high marker density.

The adequacy of the distal resection margin after preoperative chemoradiotherapy for rectal cancer

AIM

The study aimed to determine the adequacy of the distal margin in patients having preoperative chemoradiotherapy (CRT) followed by restorative surgery for rectal cancer.

METHOD

A total of 368 patients with locally advanced rectal cancer treated for cure at our institution between July 1999 and March 2009 were included in the study. All underwent preoperative CRT and sphincter-sparing surgery. The distal margin and other factors were examined for their effect on recurrence and survival. The median duration of follow-up was 48 months.

RESULTS

The length of distal margin ranged from 0 to 9.0 cm (median 1.5 cm). The pelvic control and disease-free survival rates at 5 years for patients with a margin of ≤ 3 mm were no different from those in whom it was > 3 mm (P = 0.6 and 0.8). The 5-year pelvic control rates between the ≤ 3 mm and > 3 mm groups were 66.7 and 86.2% in patients with a ypT3-4 tumour (P = 0.049) and 70.0 and 89.1% in patients who showed no response to CRT (P = 0.039).

CONCLUSION

The results suggest that a distal margin of < 3 mm in the surgical specimen after preoperative CRT is associated with a lower rate of pelvic tumour control at 5 years in patients with Stage ypT3-4 tumours or in those who do not respond to CRT.