Peripheral zone thickness in preoperative MRI is predictive of Trifecta achievement after Holmium laser enucleation of the prostate (HoLEP).

PURPOSE: To investigate various anatomical features of the prostate using preoperative MRI and patients' clinical factors to identify predictors of successful Holmium:YAG laser enucleation of the prostate (HoLEP). METHODS: 71 patients who had received HoLEP and undergone a 3.0-T prostate MRI scan within 6 months before surgery were retrospectively enrolled. MRI features (e.g., total prostate and transitional zone volume, peripheral zone thickness [PZT], BPH patterns, prostatic urethral angle, intravesical prostatic protrusion, etc.) and clinical data (e.g., age, body mass index, surgical technique, etc.) were analyzed using univariable and multivariable logistic regression to identify predictors of successful HoLEP. Successful HoLEP was defined as achieving the Trifecta, characterized by the contemporary absence of postoperative complications within 3 months, a 3-month postoperative maximum flow rate (Qmax) > 15 mL/s, and no urinary incontinence at 3 months postoperatively. RESULTS: Trifecta achievement at 3 months post-surgery was observed in 37 (52%) patients. Patients with Trifecta achievement exhibited a lower preoperative IPSS-quality of life score (QoL) (4.1 vs. 4.5, P = 0.016) and a thinner preoperative peripheral zone thickness (PZT) on MRI (7.9 vs.10.3 mm, P < 0.001). In the multivariable regression analysis, a preoperative IPSS-QoL score < 5 (OR 3.98; 95% CI, 1.21-13.07; P = 0.017) and PZT < 9 mm (OR 11.51; 95% CI, 3.51-37.74; P < 0.001) were significant predictors of Trifecta achievement after HoLEP. CONCLUSIONS: Alongside the preoperative QoL score, PZT measurement in prostate MRI can serve as an objective predictor of successful HoLEP. Our results underscore an additional utility of prostate MRI beyond its role in excluding concurrent prostate cancer.

EPHA3 Contributes to Epigenetic Suppression of PTEN in Radioresistant Head and Neck Cancer.

EPHA3, a member of the EPH family, is overexpressed in various cancers. We demonstrated previously that EPHA3 is associated with radiation resistance in head and neck cancer via the PTEN/Akt/EMT pathway; the inhibition of EPHA3 significantly enhances the efficacy of radiotherapy in vitro and in vivo. In this study, we investigated the mechanisms of PTEN regulation through EPHA3-related signaling. Increased DNA methyltransferase 1 (DNMT1) and enhancer of zeste homolog 2 (EZH2) levels, along with increased histone H3 lysine 27 trimethylation (H3K27me3) levels, correlated with decreased levels of PTEN in radioresistant head and neck cancer cells. Furthermore, PTEN is regulated in two ways: DNMT1-mediated DNA methylation, and EZH2-mediated histone methylation through EPHA3/C-myc signaling. Our results suggest that EPHA3 could display a novel regulatory mechanism for the epigenetic regulation of PTEN in radioresistant head and neck cancer cells.

Enhanced mechanical and wear properties of Al6061 alloy nanocomposite reinforced by CNT-template-grown core-shell CNT/SiC nanotubes.

Novel one-dimensional template-grown coaxial SiC@carbon nanotubes (SiC@CNTs) were fabricated using a chemical vapor deposition method. To facilitate the formation of SiC on CNT template, a molecular-level mixing process was used to coat the surface of commercial multiwalled carbon nanotubes (MWCNTs) by Fe2O3. These Fe-CNTs were transformed into SiC@CNT nanotubes, which were then mixed with Al6061 alloy and consolidated by spark plasma sintering to obtain Al6061-SiC@CNT nanocomposites. The addition of 5 vol% SiC@CNT resulted in 58% enhancement in Young's modulus and 46% enhancement in yield strength. Furthermore, the friction coefficient was reduced by 31% and the specific wear rate was reduced by 45%. The enhancement effect of Al6061-SiC@CNT on the mechanical and tribological properties was much greater than those of traditional nanoparticles, nanowires, and whiskers of SiCs. The extraordinary strengthening behavior of SiC@CNT, when compared with that of other SiC analogues, is attributed to the coaxial structure consisting of a SiC shell and CNT core. This coaxial structure enhanced the mechanical and tribological properties beyond that attainable with traditional SiC-derived reinforcements.

Transnasal Placement of a Balloon-Expandable Metallic Stent: Human Cadaver Study of the Eustachian Tube.

PURPOSE: To investigate the technical feasibility of stent placement in the cartilaginous portion of the Eustachian tube (ET). MATERIALS AND METHODS: Twelve ETs of 6 cadavers were used. Two different-sized stents were placed on either the right (2.5 mm in diameter) or left (3.5 mm in diameter) side of the ET. The procedural feasibility was assessed by subtraction Eustachian tubography, computed tomography before and after the procedure, and fluoroscopic and endoscopic images. The stent location, inner luminal diameter of the stented ET, radiation dose, procedural time, and fluoroscopy time were analyzed. RESULTS: Stent placement was successful in 11 of 12 cadaveric specimens without procedure-related complications. In the 1 specimen, the balloon catheter with crimped stent was passed into the bony canal of the ET without any resistance. The distal end of the stent was located in the middle ear cavity. Stents were located within the cartilaginous portion of the ET (n = 1), the proximal tip bridging the nasopharyngeal orifice of the ET (n = 5), or the proximal end of the stent protruded from the tubal orifice (n = 5). The mean luminal diameter in the outer segment was significantly smaller than in the middle (P < .001) and inner (P < .001) segments. The mean procedure time was 128 ± 37 seconds. The mean radiation dose and fluoroscopy time of each cadaver were 3235.4 ± 864.8 cGy/cm2 and 139 ± 49 seconds, respectively. CONCLUSIONS: Stent placement of the ET under endoscopic and fluoroscopic guidance is technically feasible in a human cadaver model.

Fluoroscopic subtraction Eustachian tubography: initial feasibility test in a cadaver model.

OBJECTIVES: To evaluate the technical feasibility of direct Eustachian tube catheterisation and subtraction Eustachian tubography in a cadaver model. METHODS: A total of 12 separate sessions were performed on both sides of the Eustachian tube (ET) in six human cadavers. Cadavers were positioned for the submentovertical view on a fluoroscopy table. Endoscopy-guided ET selection was used in the first three cadavers, whereas fluoroscopy-guided ET selection was used in the remaining three. Eustachian tubography was performed by injecting 2 ml of contrast media through a 5-Fr catheter. We recorded the success of ET selection, number of attempts, procedure time, and tubography quality using native and subtraction images (range, 0-3). RESULTS: Both endoscopy- and fluoroscopy-guided selections were successfully performed in five of six sessions (83.3%). There were no statistically significant differences between the endoscopy- and fluoroscopy-guided procedures in terms of the number of attempts, procedure time, rate of immediate contrast leak to the middle ear cavity, and quality of tubography (p > 0.05). An excellent quality of tubography was obtained in 83.3% (10 of 12 sessions) of subtraction images and in 33.3% (4 of 12 sessions) of native images. The tubography quality score was significantly higher for the subtraction images than for the native images (p = 0.04). CONCLUSION: Subtraction Eustachian tubography using direct catheterisation seems to be technically feasible. The entire ET can be well visualised; thus, this technique can be used as a simple tool for assessment of ET function and anatomy. KEY POINTS: • Direct catheterisation of the Eustachian tube is technically feasible. • The entire Eustachian tube could be well visualised by direct Eustachian tubography. • Subtraction Eustachian tubography images have better image quality than native images. • Subtraction Eustachian tubography can provide objective assessment of ET function and anatomy.

Value of imaging study in predicting pelvic lymph node metastases of uterine cervical cancer.

PURPOSE: To evaluate the diagnostic accuracy of computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT) in predicting pelvic lymph node (LN) metastases in patients with cervical cancer. MATERIALS AND METHODS: From January 2009 to March 2015, 114 patients with FIGO stage IA1-IIB uterine cervical cancer who underwent hysterectomy with pelvic lymphadenectomy and took CT, MRI, and PET/CT before surgery were enrolled in this study. The criteria for LN metastases were a LN diameter ≥1.0 cm and/or the presence of central necrosis on CT, a LN diameter ≥1.0 cm on MRI, and a focally increased FDG uptake on PET/CT. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for pelvic LN metastases were estimated. RESULTS: The sensitivity, specificity, PPV, NPV, and accuracy for detection of pelvic LN metastases were 51.4%, 85.9%, 41.3%, 90.1%, and 80.3% for CT; 24.3%, 96.3%, 56.3%, 86.8%, and 84.6% for MRI; and 48.6%, 89.5%, 47.4%, 90.0%, and 82.9% for PET/CT, respectively. The sensitivity of PET/CT and CT was higher than that of MRI (p=0.004 and p= 0.013, respectively). The specificity of MRI was higher than those of PET/CT and CT (p=0.002 and p=0.001, respectively). The difference of specificity between PET/CT and CT was not statistically significant (p=0.167). CONCLUSION: These results indicate that preoperative CT, MRI, and PET/CT showed low to moderate sensitivity and PPV, and moderate to high specificity, NPV, and accuracy. More efforts are necessary to improve sensitivity of imaging modalities in order to predict pelvic LN metastases.

Percutaneous treatment of central venous stenosis in hemodialysis patients: long-term outcomes.

The purpose of this study was to evaluate the long-term outcomes of endovascular treatment of central venous stenosis in patients with arteriovenous fistulas (AVFs) for hemodialysis. Five hundred sixty-three patients with AVFs who were referred for a fistulogram were enrolled in this study. Among them, 44 patients showed stenosis (n = 35) or occlusions (n = 9) in the central vein. For the initial treatment, 26 patients underwent percutaneous transluminal angioplasty (PTA) and 15 patients underwent stent placements. Periods between AVF formation and first intervention ranged from 3 to 144 months. Each patient was followed for 14 to 60 months. Procedures were successful in 41 of 44 patients (93.2%). Primary patency rates for PTA at 12 and 36 months were 52.1% and 20.0%, and assisted primary patency rates were 77.8% and 33.3%, respectively. Primary patency rates for stent at 12 and 36 months were 46.7% and 6.7%, and assisted primary patency rates were 60.0% and 20.0%, respectively. Fifteen of 26 patients with PTAs underwent repeated interventions because of restenosis. Fourteen of 15 patients with a stent underwent repeated interventions because of restenosis and combined migration (n = 1) and shortening (n = 6) of the first stent. There was no significant difference in patency between PTAs and stent placement (p > 0.05). Average AVF patency duration was 61.8 months and average number of endovascular treatments was 2.12. In conclusion, endovascular treatments of central venous stenosis could lengthen the available period of AVFs. There was no significant difference in patency between PTAs and stent placement.

Portosystemic pressure gradient during transjugular intrahepatic portosystemic shunt with Viatorr stent graft: what is the critical low threshold to avoid medically uncontrolled low pressure gradient related complications?

BACKGROUND: Inappropriately decreased portosystemic pressure gradient (PSG) during transjugular intrahepatic portosystemic shunt (TIPS) can cause fatal complications but the critical low threshold of PSG is still not clear. The aim of the present study was to evaluate the critical low threshold of PSG during TIPS. METHODS: Sixty-six patients with cirrhosis who successfully underwent de novo TIPS with Viatorr stent grafts were studied. Medically uncontrolled low pressure gradient (LPR) complication was defined as when a patient died, or when acute transplantation or a TIPS reduction procedure was performed due to refractory encephalopathy or the deterioration of hepatic function within 3 months after the procedure. For the determination of the risk group for medically uncontrolled LPR complications, the Child-Pugh score and the model of end-stage liver disease (MELD) score showing a 100% negative predictive value was decided on as a threshold for each score. The risk group was defined when either of both scores was higher than its threshold. For the determination of a critical low post-TIPS PSG, a value of post-TIPS PSG showing the highest discrimination power on the receiver operating characteristic (ROC) curve in the risk group was decided on as a critical low threshold of PSG. The medically uncontrolled LPR complication rates of the patients with the determined threshold or lower were evaluated for the risk group. RESULTS: Medically uncontrolled LPR complications developed in nine patients (13.6%). Five patients died and four patients had TIPS reduction procedures. Patients with more than 10 on the Child-Pugh score or more than 14 on the MELD score were determined to be the risk group and 34 patients were included. The critical lower threshold of the post-TIPS PSG showing the highest discrimination power on the ROC curve was 5 mmHg (sensitivity 100%, specificity 72%), and the medically uncontrolled LPR complication rates of the patients with 5 mmHg or lower on the post-TIPS PSG were 56.3% (9/16) in the risk group. CONCLUSIONS: The critical threshold of the post-TIPS PSG to avoid the medically uncontrolled LPR complications of TIPS was >5 mmHg. The PSG should not be reduced below this level in the risk group.

Transcatheter arterial chemoembolization of hepatocellular carcinoma with hepatic arteriovenous shunt after temporary balloon occlusion of hepatic vein.

PURPOSE: Hepatocellular carcinoma with hepatic artery to hepatic vein (AV) shunt has increased risk of pulmonary complications during transcatheter arterial chemoembolization (TACE). The purpose of this study is to assess temporary balloon occlusion as a means of preventing pulmonary complications during TACE of hepatocellular carcinoma with AV shunt. MATERIALS AND METHODS: Eleven hepatocellular carcinoma patients (M: F = 9:2; mean age, 48 years) with angiographically evident AV shunt underwent TACE with occlusion of the shunt-draining hepatic veins using temporary occlusion balloon catheters. All tumors were in the right lobe, and all AV shunts were between the right hepatic artery and right hepatic vein. The occlusion balloon was inserted via femoral (n = 6) or jugular (n = 5) venous access. The balloon diameter ranged from 8.5 to 11.5 mm and time of ballooning was 3 to 15 minutes (mean, 9.5 minutes). TACE was performed using emulsion of iodized oil and doxorubicin, followed by Gelfoam embolization. The balloon was deflated immediately after chemoembolization, and physical examination and chest radiography were performed. Follow-up computed tomography was performed within 2 weeks after TACE to evaluate the result and pulmonary complications. RESULTS: The technical success rate was 100%. There was no symptom, sign, or radiographic evidence of pulmonary complication. Follow-up computed tomography revealed complete iodized oil uptake by the tumor in eight patients and incomplete uptake by the tumor in three patients. There was no iodized oil uptake in the lungs. CONCLUSIONS: Temporary balloon occlusion of the hepatic vein in hepatocellular carcinoma with AV shunt allowed completion of TACE using conventional method while preventing pulmonary complications.