Image findings of anti-neutrophil cytoplasmic antibody-associated vasculitis involving the skull base.

AIM: To investigate computed tomography (CT) and magnetic resonance imaging (MRI) features of skull bases involving anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). MATERIALS AND METHODS: A retrospective review was undertaken to identify an institutional historical cohort of 17 patients with confirmed AAV who underwent CT or MRI and had skull base involvement between 2002 and 2021. Two radiologists reviewed the extent and features of the lesions, bone changes, and other MRI findings. RESULTS: A total of 17 patients (12 men; mean age ± standard deviation, 46.5 ± 17.1 years) were selected. AAV presented as infiltrative lesions with involvement at various sites. Most cases involved the paranasal sinuses (PNS; 88%, 15/17), nasopharynx (88%, 15/17), pterygopalatine fossa (82%, 14/17), and parapharyngeal space (82%, 14/17), frequently accompanied by mucosal irregularity of the PNS and nasopharynx (71%, 12/17). Central skull base and temporal bone involvement were seen in 53% (9/17) and 38% (6/16) of cases, respectively. On T1-weighted imaging (WI) and T2WI MRI, all lesions (15/15) showed predominant signal iso-intensity to grey matter. CONCLUSIONS: Although radiological findings of AAV are non-specific and skull base involvement is less common, AAV may be considered if infiltrative lesions predominantly involving the PNS, nasopharynx, pterygopalatine fossa, and parapharyngeal space with combined bone changes of skull base are seen.

An objective skin-type classification based on non-invasive biophysical parameters.

BACKGROUND: Despite the invention of various non-invasive bioengineering tools, skin-type analysis has largely been based on subjective assessments. However, advancements in the functional cosmetic industry and artificial intelligence-assisted dermatology are creating a greater demand for an objective skin-type classification system. OBJECTIVES: To propose an objective skin-type classification system solely based on non-invasive, bioengineering devices; provide reference values applicable to the Korean population; and compare our reference values with those of published studies. METHODS: Biophysical parameter measurements were obtained from the 2018 International Skin Characteristics Data Bank Project conducted by the Foundation of Korea Cosmetic Industry Institute. The participants were 434 healthy South Korean adults. Each participant was assessed using eight bioengineering devices (Tewameter® , pH-meter® , Corneometer® , Sebumeter® , Cutometer® , Spectrophotometer® , PRIMOS® lite, and Janus® ). The measurements were divided into tertiles to determine reference points. RESULTS: Our objective skin-type classification consists of five main categories (sensitivity, hydration, oiliness, elasticity, and skin tone) and five corresponding subcategories (erythema, roughness, pores, wrinkles, and pigmentation, respectively). Each skin type was assigned based on the reference point of the biophysical parameter, which was established as the tertile value associated with 'unfavourable' skin characteristics. Individuals were categorized as having sensitive skin when the TEWL scores were over 18.0 g/m2 /h or the pH was over 5.45; dehydrated skin when the corneometric value measured below 47.17 A.U.; oily skin when the sebumetric value exceeded 70 µg/cm2 ; and loose skin when the cutometric R2 value was below 0.68 E/mm. CONCLUSIONS: This study is the first to provide a comprehensive skin-type classification system based solely on non-invasive biophysical parameters. As measurement data accumulate, the reference points will progress to become more accurate, and they will be subdivided according to gender, age, and ethnic group. Therefore, our classification system serves as a basis for artificial intelligence-based skin-type analysis.

PIN1 is a new therapeutic target of craniosynostosis.

Gain-of-function mutations in fibroblast growth factor receptors (FGFRs) cause congenital skeletal anomalies, including craniosynostosis (CS), which is characterized by the premature closure of craniofacial sutures. Apert syndrome (AS) is one of the severest forms of CS, and the only treatment is surgical expansion of prematurely fused sutures in infants. Previously, we demonstrated that the prolyl isomerase peptidyl-prolyl cis-trans isomerase interacting 1 (PIN1) plays a critical role in mediating FGFR signaling and that Pin1+/- mice exhibit delayed closure of cranial sutures. In this study, using both genetic and pharmacological approaches, we tested whether PIN1 modulation could be used as a therapeutic regimen against AS. In the genetic approach, we crossbred Fgfr2S252W/+, a mouse model of AS, and Pin1+/- mice. Downregulation of Pin1 gene dosage attenuated premature cranial suture closure and other phenotypes of AS in Fgfr2S252W/+ mutant mice. In the pharmacological approach, we intraperitoneally administered juglone, a PIN1 enzyme inhibitor, to pregnant Fgfr2S252W/+ mutant mice and found that this treatment successfully interrupted fetal development of AS phenotypes. Primary cultured osteoblasts from Fgfr2S252W/+ mutant mice expressed high levels of FGFR2 downstream target genes, but this phenotype was attenuated by PIN1 inhibition. Post-translational stabilization and activation of Runt-related transcription factor 2 (RUNX2) in Fgfr2S252W/+ osteoblasts were also attenuated by PIN1 inhibition. Based on these observations, we conclude that PIN1 enzyme activity is important for FGFR2-induced RUNX2 activation and craniofacial suture morphogenesis. Moreover, these findings highlight that juglone or other PIN1 inhibitors represent viable alternatives to surgical intervention for treatment of CS and other hyperostotic diseases.

Diagnostic performance of MRI to detect metastatic cervical lymph nodes in patients with thyroid cancer: a systematic review and meta-analysis.

AIM: To evaluate the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of metastatic cervical lymph nodes. MATERIALS AND METHODS: Ovid-MEDLINE and EMBASE databases were searched up until 12 June 2018. Eleven articles were included in the qualitative systematic review and nine of the 11 in the quantitative analysis. Two radiologists independently performed data extraction and methodological quality assessment using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A qualitative systematic review and quantitative analysis were performed, followed by a meta-regression analysis to determine factors causing heterogeneity. RESULTS: The pooled sensitivity and specificity in the diagnosis of metastatic cervical lymph nodes were 80% (95% confidence interval [CI]: 68-88%) and 85% (95% CI: 63-95%), respectively. The sensitivity and false-positive rate (correlation coefficient, 0.655) showed a positive correlation due to a threshold effect, which was responsible for heterogeneity across the studies, as indicated by a Q-test (p<0.01) and Higgins I2 statistic (sensitivity, I2=90.11%; specificity, I2=92.49%). In the meta-regression analysis, fat-suppressed imaging, and the analysis method were significant factors influencing the heterogeneity in diagnostic performance. CONCLUSIONS: MRI shows moderate diagnostic performance in the diagnosis of metastatic lymph nodes in patients with thyroid cancer in the neck. MRI may be an optional or complementary imaging method to ultrasound or computed tomography (CT) in thyroid cancer patients.

High-resolution MRI using compressed sensing-sensitivity encoding (CS-SENSE) for patients with suspected neurovascular compression syndrome: comparison with the conventional SENSE parallel acquisition technique.

AIM: To retrospectively compare sensitivity encoding (SENSE) and compressed sensing-sensitivity encoding (CS-SENSE) for high resolution (HR) cranial nerve magnetic resonance imaging (MRI) in a clinical population. MATERIAL AND METHODS: Twenty consecutive patients who were clinically suspected of neurovascular compression syndrome (NVCS) were enrolled in this study. HR three-dimensional isotropic T2-weighted fast spin-echo (T2 VISTA) sequences with SENSE or CS-SENSE, and contrast-enhanced three-dimensional T1-turbo field-echo (CE 3D T1 TFE) with SENSE or CS-SENSE, were compared using quantitative and qualitative methods by two board-certified neuroradiologists. RESULTS: For the T2 VISTA, CS-SENSE was significantly superior to SENSE in terms of cerebrospinal fluid homogeneity. For CE 3D T1 TFE, CS-SENSE was significantly superior to SENSE in terms of the existence of ghost artefact and the signal-to-noise ratio (SNR) of the pontine parenchyma. There was no significant difference in overall image quality between the two techniques. Compared with SENSE, CS-SENSE reduced the scan time to 44.2% of that with SENSE on T2 VISTA, and to 66.1% of that with SENSE of the CE 3D T1 TFE, with the differences being statistically significant (p<0.01, both). CONCLUSION: For T2 VISTA and CE 3D T1 TFE imaging of patients with suspected NVCS, CS-SENSE appears to offer superior reductions in motion artefact and scan time relative to SENSE, without a loss of overall image quality.

Are patients with mild to moderate renal impairment on metformin or other oral anti-hyperglycaemic agents at increased risk of contrast-induced nephropathy and metabolic acidosis after radiocontrast exposure?

AIM: To investigate whether the use of metformin during computed tomography (CT) with radiocontrast agents increases the risk of contrast-induced nephropathy (CIN) and metabolic acidosis after CT in type 2 diabetes patients with mild to moderate renal failure. MATERIALS AND METHODS: Patient records from January 2015 to December 2017 were reviewed retrospectively. A total of 374 patients were included in the final analysis. Of them, 157 patients received metformin, and 217 patients were taking other oral hypoglycaemic agents (OHAs) during radiocontrast administration. RESULTS: No significant difference in CIN incidence was observed between the metformin use group and the other OHAs group (p=0.085). Metabolic acidosis after CT was seen in 91 (58%) patients who used metformin and 141 (65%) patients who were taking other OHAs. There was no relationship between metabolic acidosis after CT and the use of metformin (p=0.195). Metabolic acidosis after radiocontrast agent exposure was associated with malignant disease, low serum albumin level, and low serum total CO2 level at baseline. CONCLUSION: These data show that other factors, but not metformin use, are associated with metabolic acidosis after radiocontrast agent exposure in patients with reduced renal function. These data support current recommendations that there is no need to discontinue metformin before CT using radiocontrast agents in patients with mild to moderate renal failure.

Human skin-depigmenting effects of resveratryl triglycolate, a hybrid compound of resveratrol and glycolic acid.

OBJECTIVES: Resveratryl triglycolate (RTG) is a hybrid compound derived by the esterification of resveratrol with glycolic acid. This compound has been previously shown to inhibit cellular melanin synthesis in vitro. This study aimed to examine the in vivo skin-depigmenting efficacy of RTG in human participants. METHODS: In total, 22 women aged between 25 and 49 years with Fitzpatrick skin type III or IV were enrolled. Their forearms were exposed to UV to induce artificial pigmentation. The test product containing 0.4% RTG or the control product was applied twice daily for up to 8 weeks after the artificial pigmentation. The participants visited the research centre every 2 weeks and were subjected to skin assessments. RESULTS: Visual assessment of pigmentation degree and instrumental analysis of melanin index, skin lightness (L* value) and skin colour (individual typology angle, ITAo ) indicated enhanced depigmentation of the skin in the test group, compared with the control group, in Weeks 6 and 8 (P < 0.05). No adverse skin reactions were observed in any of the participants during the entire test. CONCLUSION: This study demonstrated the skin-depigmenting effects of RTG in human participants.

Interobserver reproducibility of maximal axial diameter and tumour volume measurements from CT of patients with head and neck squamous cell carcinoma.

AIM: To evaluate the interobserver reproducibility of computed tomography (CT) measurements of maximum tumour diameter and tumour volume for head and neck squamous cell carcinoma. MATERIALS AND METHODS: Eighty consecutive patients who underwent neck CT for the initial evaluation of head and neck squamous cell carcinoma were included in this retrospective study. Two radiologists independently measured the maximal axial diameter and volume of tumours. The reproducibility between the two observers was assessed using 95% Bland-Altman limits of agreement, reproducibility coefficient, within-subject coefficient of variation, and intraclass correlation coefficient with subgroup analysis according to tumour location. Logistic regression analysis was performed to identify the risk factors for high variability in tumour volume. RESULTS: The 95% limits of agreement for maximal axial diameter and tumour volume were ±22.3% and ±42.8%, respectively. The within-subject coefficient of variation and reproducibility coefficient were 7.9% and 0.564 for maximal axial diameter and 22.9% and 5.069 for tumour volume. All intraclass correlation coefficients for maximal axial diameter and tumour volume demonstrated excellent agreement (all intraclass correlation coefficients >0.9). Peritumoural infiltration (odds ratio: 7.189; confidence interval: 1.815-28.469; p=0.005) was an independent risk factor for high interobserver variability. CONCLUSION: Changes in maximum axial diameter and tumour volume of <22.3% and 42.8%, respectively, were in the range of measurement error on CT. The presence of peritumoural infiltration on CT increases the error in tumour volume measurement.

Risk of malignancy according to sub-classification of the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category in the Bethesda system for reporting thyroid cytopathology.

OBJECTIVE: According to the Bethesda System for Reporting Thyroid Cytopathology, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is a heterogeneous category that includes cases with architectural and/or nuclear atypia insufficient to warrant classification as malignant neoplasms. The ambiguous and descriptive characteristics of the AUS/FLUS category mean that the impact of the present guidelines on repeat fine needle aspiration (FNA) is unclear. The present study reclassified AUS/FLUS cases into four sub-categories and then correlated them with histological or cytological follow-up data to clarify the risk of malignancy. METHODS: Ninety-four cases of AUS/FLUS with available follow-up data were reviewed and assigned to one of four sub-categories: (i) AUS-N (nuclear atypia); (ii) AUS-A (architectural atypia); (iii) AUS-O (predominant oncocytic changes); and (iv) AUS-N/A (both nuclear and architectural atypia). The four sub-categories were correlated with subsequent histological or cytological follow-up data, including core needle biopsy, resection, or repeat FNA. RESULTS: Malignancy was identified in 34 of 94 cases (36.2%). The upper limit estimate for malignancy was 43.6%, and the lower limit estimate was speculated as 9.8%. The malignancy rate was highest in cases within the AUS-N sub-category (65.8%, range 16.6%-78.1%). CONCLUSIONS: The present study suggests that cases in the AUS/FLUS category have a higher risk of malignancy than previously thought. Because of the heterogeneous nature of the AUS/FLUS category, further sub-classification might be more effective in achieving appropriate risk stratification and better clinical management.

The association between use of metformin and change in serum CO2 level after administration of contrast medium.

AIM: To evaluate the changes in serum creatinine and total CO2 levels in patients receiving metformin during administration of contrast medium. MATERIALS AND METHODS: Patient records from January 2012 to December 2012 after the administration of contrast medium were reviewed retrospectively. A total of 924 patients were included for the final analysis. Of them, 105 received metformin during contrast medium administration, 112 were taking other oral hypoglycaemic agents, and 707 patients were not diabetic (controls). RESULTS: No significant change in total CO2 levels was detected (p=0.678). Metabolic acidosis was present in 33 (31.4%) metformin users, 31 (28.6%) other oral hypoglycaemic agent users, and 153 (21.6%) control patients. In the present logistic regression analysis, age, baseline levels of creatinine, and total CO2 levels were associated with metabolic acidosis after contrast medium exposure. CONCLUSION: These data indicate the presence of a coexisting risk factor, other than metformin use, associated with metabolic acidosis after contrast medium exposure. No relationship was found between the use of metformin and metabolic acidosis during contrast medium exposure.