Blockage of CSF Outflow in Rats after Deep Cervical Lymph Node Ligation Observed Using Gd-based MR Imaging.

PURPOSE: To investigate whether deep cervical lymph node (DCLN) ligation alters intracranial cerebrospinal fluid (CSF) tracer dynamics and outflow using a rat model with intrathecal dynamic contrast-enhanced (DCE) MRI. METHODS: Six bilateral DCLN-ligated and six sham-operated rats were subjected to DCE MRI with Gd-BTDO3A, and dynamic T1-weighted images were acquired. ROIs were collected from the CSF at the C1 level (CSF_C1), CSF between the olfactory bulbs (CSF_OB), CSF at the pituitary recess (CSF_PitR), and CSF at the pineal recess (CSF_PinR), upper nasal turbinate (UNT), olfactory bulbs, cerebrum, and the jugular region. Time-intensity curves were evaluated, and the maximum slope, peak timing, peak signal ratio, and elimination half-life for the four CSF ROIs and UNT were calculated and compared. RESULTS: Delayed tracer arrival in the rostral CSF space and the nasal cavity with tracer retention in the ventral CSF space were observed in the ligation group. The maximum slopes were smaller in the ligation group at UNT (sham: 0.075 ± 0.0061, ligation: 0.044 ± 0.0086/min, P = 0.011). A significant difference was not detected in peak timings. The peak signal ratio values were lower in the ligation group at UNT (sham: 2.12 ± 0.19, ligation: 1.72 ± 0.11, P = 0.011). The elimination half-life was delayed in the ligation group at CSF_C1 (sham: 30.5 ± 2.70, ligation: 44.4 ± 12.6 min, P = 0.043), CSF_OB (sham: 30.2 ± 2.67, ligation: 44.8 ± 7.47 min, P = 0.021), and CSF_PitR (sham: 30.2 ± 2.49, ligation: 41.3 ± 7.57 min, P = 0.021). CONCLUSION: The DCLN ligation in rats blocked CSF outflow into the nasal cavity and caused CSF retention.

Mechanical Properties of a 3 Dimensional-Printed Transparent Flexible Resin Used for Vascular Model Simulation Compared with Those of Porcine Arteries.

PURPOSE: To develop a vascular intervention simulation model that replicates the characteristics of a human patient and to compare the mechanical properties of a 3-dimensional (3D)-printed transparent flexible resin with those of porcine arteries using the elastic modulus (E) and kinetic friction coefficient (µk). MATERIALS AND METHODS: Resin plates were created from a transparent flexible resin using a 3D printer. Porcine artery plates were prepared by excising the aorta. E values and the adhesive strengths of the resin and arterial surfaces toward a polyethylene plate, were measured with a tensile-compressive mechanical tester. Resin transparency was measured using an ultraviolet-visible light spectrometer. The µk value of the resin plate surface after applying silicone spray for 1-5 seconds and that of the artery were measured using a translational friction tester. RESULTS: E values differed significantly between the arteries and resin plates at each curing time (0.20 MPa ± 0.04 vs 8.53 MPa ± 2.37 for a curing time of 1 minute; P < .05). The resin was stiffer than the arteries, regardless of the curing times. The visible light transmittance and adhesive strength of the resin decreased as the curing time increased. The adhesive strength of the artery was the lowest. The µk value of the silicone-coated resin surface created by applying silicone for 2-3 seconds (thickness of the silicone layer, 1.6-2.0 µm) was comparable with that of the artery, indicating that the coating imparted a similar slippage to the resin as to the living artery. CONCLUSIONS: A transparent flexible resin is useful for creating a transparent and slippery vascular model for vascular intervention simulation.

Single-Session Intranodal Glue Embolization for Postsurgical Refractory Groin Lymphorrhea: A Case Report.

A 90-year-old female presented with poor right groin wound healing due to lymphorrhea and infection following a surgical cutdown procedure for arterial revascularization. Although negative pressure wound therapy (NPWT) and inguinal lymphadenectomy were performed, infection and lymphorrhea did not heal. Lymphangiography via a right inguinal lymph node revealed lymphatic leakage in the wound. Intranodal glue embolization (IGE) was performed by injecting 0.6 mL of 33% n-butyl-2 cyanoacrylate (NBCA)-lipiodol mixture. Additionally, the presence of glue in an open wound was directly confirmed in this case. After embolization, lymphorrhea ceased, and the wound healed completely. No lymphorrhea recurrence or complications were observed for 6 months. This case suggests that IGE could be an effective treatment for groin lymphorrhea.

Usefulness of preoperative simulation with patient-specific hollow vascular models for high-flow renal arteriovenous fistula embolization using a preloading coil-in-plug technique.

The development of three-dimensional printers has facilitated the creation of patient-specific hollow vessel models. Preoperative simulations using these types of models have improved our ability to select appropriate devices and embolic materials before performing complex endovascular procedures. This report describes 2 cases of high-flow renal arteriovenous fistulas (r-AVFs) that were successfully treated via short-segment embolization using the preloading coil-in-plug (p-CIP) technique. To our knowledge, this is the first report of r-AVF being treated using the p-CIP technique. Our findings demonstrate that preoperative simulation has the potential to improve the safety and reliability of complex vascular embolization procedures.

Successful transvenous embbolization for type II uterine arteriovenous malformation: A case report.

A 40-year-old female (gravida 3 para 1) presented with menstrual, urinary, and anal pain. Computed tomography revealed type II acquired uterine arteriovenous malformation, a common dilated venous sac with bilateral uterine arteries, and multiple branches of iliac arteries draining to the bilateral ovarian veins. Venous sac transvenous embolization via the left ovarian vein of dominant outflow was planned, since complete arteriovenous malformation occlusion was difficult with super-selective transarterial embolization of multiple feeders. Therefore, transarterial embolization of the minor feeder was performed before completing transvenous embolization using coils and 50% glue under left iliac artery flow control. Immediately thereafter, angiography confirmed the complete disappearance of the uterine arteriovenous malformation, and all pain symptoms remitted. In conclusion, transvenous embolization combined with adjunctive transarterial embolization can be an effective and radical treatment for type II uterine arteriovenous malformations.

Prediction of unilateral hyperaldosteronism on adrenal vein sampling using captopril challenge test in patients with primary aldosteronism.

Captopril challenge test (CCT) is a simple and safe confirmatory test for primary aldosteronism (PA). We investigated the effectiveness of the indices after captopril administration for prediction of unilateral hyperaldosteronism (UHA) on adrenal vein sampling (AVS). We studied 238 patients with PA who had CCT and successful AVS between July 2007 and December 2019 in Sapporo City General Hospital. Receiver operating characteristic (ROC) curve analysis showed that the diagnostic performance for prediction of UHA on AVS in regard to the reduction rate of plasma aldosterone concentration (PAC) after captopril administration was inferior to aldosterone to renin ratio (ARR) and PAC (area under the ROC curve 0.72 vs. 0.84, 0.72 vs. 0.89, respectively, both p < 0.01). Based on the optimal cut-off values in ARR (897 pg/mL/ng/mL/h, sensitivity 64.6%, specificity 93.0%) and PAC (203 pg/mL, sensitivity 73.9%, specificity 93.0%) after captopril administration, the patients were divided into three groups: (1) both positive, (2) one positive, and (3) both negative. The prevalence of UHA on AVS in the three groups were 90.0%, 52.9%, and 7.3%, respectively. In the first group, 31 of 32 patients with unilateral nodular lesion on CT had an ipsilateral unilateral AVS. In conclusion, the combination of post-captopril ARR and PAC is useful for prediction of laterality diagnosis on AVS. AVS is strongly recommended in patients with both positive or one positive results for the optimal cut-off values of post-captopril ARR and PAC and is weakly recommended in patients with both negative results.

A case of Williams syndrome with suspected coexisting ectopic aldosterone-producing tumor in the liver.

SUMMARY: A 31-year-old man with Williams syndrome (WS) was referred to our hospital because of a 9-year history of hypertension, hypokalemia, and high plasma aldosterone concentration to renin activity ratio. A diagnosis of primary aldosteronism (PA) was clinically confirmed but an abdominal CT scan showed no abnormal findings in his adrenal glands. However, a 13-mm hypervascular tumor in the posterosuperior segment of the right hepatic lobe was detected. Adrenal venous sampling (AVS) subsequently revealed the presence of an extended tributary of the right adrenal vein to the liver surrounding the tumor. Segmental AVS further demonstrated a high plasma aldosterone concentration (PAC) in the right superior tributary vein draining the tumor. Laparoscopic partial hepatectomy was performed. The resected tumor histologically separated from the liver was composed of clear cells, immunohistochemically positive for aldesterone synthase (CYP11B2), and subsequently diagnosed as aldosterone-producing adrenal adenoma. After surgery, his blood pressure, serum potassium level, plasma renin activity and PAC were normalized. To the best of our knowledge, this is the first report of WS associated with PA. WS harbors a high prevalence of hypertension and therefore PA should be considered when managing the patients with WS and hypertension. In this case, the CT findings alone could not differentiate the adrenal rest tumor. Our case, therefore, highlights the usefulness of segmental AVS to distinguish adrenal tumors from hepatic adrenal rest tumors. LEARNING POINTS: Williams syndrome (WS) is a rare genetic disorder, characterized by a constellation of medical and cognitive findings, with a hallmark feature of generalized arteriopathy presenting as stenoses of elastic arteries and hypertension. WS is a disease with a high frequency of hypertension but the renin-aldosterone system in WS cases has not been studied at all. If a patient with WS had hypertension and severe hypokalemia, low PRA and high ARR, the coexistence of primary aldosteronism (PA) should be considered. Adrenal rest tumors are thought to arise from aberrant adrenal tissues and are a rare cause of PA. Hepatic adrenal rest tumor (HART) should be considered in the differential diagnosis when detecting a mass in the right hepatic lobe. Segmental adrenal venous sampling could contribute to distinguish adrenal tumors from HART.

Left-right differences in adrenal vein sampling for primary aldosteronism.

In adrenal venous sampling (AVS) for patients with primary aldosteronism (PA), adrenocorticotropic hormone (ACTH) stimulation generally increased the success rate. The effect of ACTH stimulation on the left-right differences of laterality diagnosis in AVS remains unclear. A total of 167 patients with PA underwent successful AVS were examined. Patients with autonomous cortisol secretion were excluded. The proportion of dominant side in AVS was compared before and after ACTH stimulation. Unilateral disease on AVS was defined as a lateralization index of more than 4, both before and after ACTH stimulation. Before ACTH stimulation, unilateral disease was more frequently observed on the right side than the left side (right 33.5% vs. left 13.8%, p < 0.01). After ACTH stimulation, unilateral disease was more frequently observed on the left side than the right side, without statistical significance (left 15.6% vs. right 10.8%, p = 0.20). Among the 56 patients who had right unilateral disease before ACTH stimulation, 17 patients (30.0%) also had right unilateral disease after ACTH stimulation. The affected side of AVS was changed from right unilateral to bilateral after ACTH stimulation in 34 (60.7%) out of 56 patients. These patients had milder PA and CT scans showed no nodular lesions on the right side. In AVS, ACTH stimulation not only decreased unilateral results but also shifted to the dominant side. Overestimation should be carefully considered when the surgical indication for the right adrenal gland was decided based on AVS results without ACTH stimulation.

Initial experience with the use of tris-acryl gelatin microspheres for transcatheter arterial embolization for enlarged polycystic liver.

PURPOSE: To assess the safety and effectiveness of transcatheter arterial embolization (TAE) with tris-acryl gelatin microspheres for patients with symptomatic enlarged polycystic liver disease (PCLD). MATERIALS AND METHODS: This prospective study was approved by our hospital's institutional review board and planned for patients with symptoms related to enlarged PCLD, such as distended abdomen, gastrointestinal obstruction and abdominal pain. Hemi-hepatic embolization with tris-acryl gelatin microspheres was performed in the hepatic artery supplying the hepatic lobe that showed the predominant presence of cysts. Each patient underwent an assessment of liver function, a questionnaire survey about symptoms, measurement of the estimated volume of the whole liver before and after TAE, and an assessment of complications associated with TAE. RESULTS: Five patients (four females, one male; mean age 52.6 ± 9.1 years) were treated. All five patients successfully completed TAE. The left lobe was treated in three patients and the right in two. After TAE, post-embolization syndrome and transient elevation of white blood cells, aspartate aminotransferase, and alanine aminotransferase occurred in all patients, but none developed hepatic insufficiency or severe complications. The mean whole liver volume was 7406 ± 2323 mL before TAE, and 6995 ± 2139 mL (95.1 ± 5.2% of the pre-therapeutic value) at 3 months and 6855 ± 2246 mL (93.3 ± 9.7%) at 12 months after TAE. Three of the five patients reported an improvement of clinical symptoms within 12 months after TAE. CONCLUSION: TAE with microspheres can be a safe and effective treatment for symptomatic enlarged PCLD.

Prediction of pancreatic anastomotic failure after pancreatic head resection using preoperative diffusion-weighted MR imaging.

PURPOSE: To determine whether the preoperative pancreatic apparent diffusion coefficient (ADC) can be used to predict the development of postoperative pancreatic anastomotic failure (PAF). MATERIALS AND METHODS: We retrospectively examined the cases of 79 patients who underwent pancreatic head resection between January 2010 and October 2013. The patients underwent 1.5-T MR imaging including diffusion-weighted imaging before surgery. The main pancreatic duct diameter (MPD), the pancreatic parenchymal thickness (PT), and the ADC of the pancreatic remnant parenchyma were measured. Two radiologists blinded to the patients' outcomes performed the measurements. The imaging parameters were compared between the patients who developed PAF and those who did not. The cut-off ADC for the development of PAF was calculated with a receiver operating characteristic analysis. RESULTS: The imaging parameters were highly correlated between the two observers. The MPD and PT did not differ significantly among the patients. The mean pancreatic ADCs were significantly higher in the patients with PAF than in those without PAF. An ADC higher than 1.50 × 10(-3) mm(2)/s (Az = 0.719, observer-1) or 1.35 × 10(-3) mm(2)/s (Az = 0.752, observer-2) was optimal for predicting the development of postoperative PAF. CONCLUSION: Measuring the preoperative non-tumorous pancreatic ADC may be useful for the prediction of a postoperative PAF.