Retrospective Review of Billowing Phenomenon-A Mimic of Endoleak Following Placement of Endologix Covered Stent for the Treatment of Abdominal Aortic Aneurysm.

BACKGROUND: Billowing is a unique computed tomography (CT) finding of the Endologix stent graft where a rim of contrast is observed outside the stent's endoskeleton but still contained within the graft cover. The purpose of this study is to evaluate the incidence and clinical outcome of billowing following an Endologix stent-graft placement. METHODS: All patients who underwent abdominal aortic aneurysm (AAA) repair with endovascular placement of an Endologix stent graft from January 2002 to September 2013 and who were followed with imaging were included in the study. The images were evaluated for the incidence of billowing. Demographics and clinical outcomes were also analyzed. RESULTS: One hundred twenty-two patients received an Endologix stent graft for AAA repair at our institution. One hundred patients qualified for this study. Eighty-four patients had billowing with the majority (70 patients) having crescentic billowing, and the remaining 14 patients having focal outpouching. Average billowing thickness measured 4.2 mm (range 1-13). Sixty-three patients with billowing had multiple follow-up CT angiograms to allow serial monitoring. Twelve patients had resolution of billowing, 11 patients had reduction in billowing size, 14 patients had no change in billowing size, and 26 patients had increase in billowing size. Patients with billowing had a statistically significant reduction in aneurysm sac size in anteroposterior and transverse dimensions (P = 0.014 and 0.009, respectively). Five cases of billowing were misdiagnosed as endoleak. Nineteen true endoleaks were identified, of which 13 cases were associated with billowing. CONCLUSIONS: Billowing does not seem to be associated with increased morbidity, mortality, increase in aneurysm size, or presence of endoleak. Billowing should be recognized as a common and benign finding of the Endologix stent.

Billowing of Endologix Powerlink Stent Graft in Post Endovascular Repair of Abdominal Aortic Aneurysm: Simultaneous Findings on CT and Ultrasound Imaging.

Endoleaks remain a main concern in endovascular aneurysm repair. A potential false positive in the diagnosis of endoleak surveillance includes "billowing," a phenomenon of the polytetrafluoroethylene plastic outer fabric of the stent graft is seen separated from the struts of the metallic endoskeleton. Contrast presents beyond the endoskeleton but is still contained within the graft. This is secondary to intermittent attachment of the graft to the endoskeleton, and is only found in the Endologix Powerlink. The finding of billowing has been previously reported and is a common knowledge by those who deploy the stent graft. We report a case where there is contemporaneous imaging on computed tomography angiography as well as on ultrasound.

Strategies for prevention of iatrogenic inferior vena cava filter entrapment and dislodgement during central venous catheter placement.

BACKGROUND: Iatrogenic migration of inferior vena cava (IVC) filters is a potentially life-threatening complication that can arise during blind insertion of central venous catheters when the guide wire becomes entangled with the filter. In this study, we reviewed the occurrence of iatrogenic migration of IVC filters in the literature and assessed methods for preventing this complication. METHODS: A literature search was conducted to identify reports of filter/wire entrapment and subsequent IVC filter migration. Clinical outcomes and complications were identified. RESULTS: A total of 38 cases of filter/wire entrapment were identified. All of these cases involved J-tip guide wires. Filters included 23 Greenfield filters, 14 VenaTech filters, and one TrapEase filter. In 18 cases of filter/wire entrapment, there was migration of the filter to the heart and other central venous structures. Retrieval of the migrated filter was successful in only four of the 18 cases, and all of these cases were complicated by strut fracture and distant embolization of fragments. One patient required resuscitation during retrieval. Successful disengagement was possible in 20 cases without filter migration. CONCLUSIONS: Iatrogenic migration of an IVC filter is an uncommon complication related to wire/filter entrapment. This complication can be prevented with knowledge of the patient's history, use of proper techniques when placing a central venous catheter, identification of wire entrapment at an early stage, and use of an appropriate technique to disengage an entrapped wire.

Novel clinical risk calculator for improving cancer predictability of mpMRI fusion biopsy in prostates.

PURPOSE: Prostate Imaging-Reporting and Data System (PI-RADS) assists in evaluating lesions on multiparametric magnetic resonance imaging (mpMRI), but there are still ongoing efforts in improving the predictive value for the presence of clinically significant PCa (csPCa) with a Gleason grade group ≥ 2 on Fusion-Biopsy. This pilot study intends to propose an easily implementable method for augmenting predictability of csPCa for PI-RADS. METHODS: A cohort of 151 consecutive patients underwent mpMRI Fusion and random US Biopsy as a result of having at least one PI-RADS lesion grade 3-5 between January 1, 2019 and December 31, 2022. A single radiologist reads all films in this study applying PI-RADS V2. RESULTS: Of the 151 consecutive patients, 49 had a highest lesion of PI-RADS 3, 82 had a highest lesion of PI-RADS 4, and 20 had a highest lesion of PI-RADS 5. For each respective group, 12, 42, and 18 patients had proven csPCa. Two predictive models for csPCa were created by employing a logistical regression with parameters readily available to providers. The models had an AUC of 0.8133 and 0.8206, indicating promising effective models. CONCLUSION: PI-RADS classification has relevant predictability problems for grades 3 and 4. By applying the presented risk calculators, patients with PI-RADS 3 and 4 are better stratified, and thus, a significant number of patients can be spared biopsies with potential complications, such as infection and bleeding. The presented predictive models may be a valuable diagnostic tool, adding additional information in the clinical decision-making process for biopsies.

Computerized metric assessment of glandular tissue volume within the peripheral zone of the prostate using combined magnetic resonance imaging and histopathology: Possible pathophysiological implications on prostate cancer development.

PURPOSE: Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are prevalent urological ailments in elderly males. Numerous clinical studies have revealed an invert association between BPH/prostate size and PCa growth. This study investigates the association between prostate size and total glandular tissue volume of the peripheral zone (GVPZ) using a unique blend of magnetic resonance imaging (MRI) and histo-anatomical imaging technique. MATERIALS AND METHODS: Patients were selected who underwent both radical prostatectomy and preoperative MRI scans. MRI scans provided quantitative measurements of prostatic zone dimensions, while histo-anatomical slides yielded quantitative data on glandular density of the peripheral zone (PZ) using imaging software. Integration of MRI and histopathology enabled the assessment of the GVPZ. Statistical analysis identified relationships between total prostate volume (TPV) and GVPZ. RESULTS: Seventy-two patients were selected and 40 cc was determined to be the optimal cutoff for small-to-moderate versus large prostates. Once the two subgroups in TPV were formed, the relationship between TPV and GVPZ was found to be highly significant (p<0.001). CONCLUSIONS: The combination of MRI and histopathology offers a novel approach for precise quantification of glandular tissue within the prostatic PZ. This study corroborates the hypothesis of PZ compression via an enlarging transition zone in larger BPH prostates, resulting in PZ glandular atrophy. Given that most PCa originates in the PZ, these results shed light on the potential protective role of larger BPH prostates against PCa growth.

Association between prostate size and glandular tissue volume of the peripheral zone via novel combined MRI and histopathology: possible pathophysiological implications on prostate cancer development.

PURPOSE: Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are the two most prevalent urologic diseases affecting elderly men. An inverse relationship between BPH/prostate size and PCa incidence is well documented in the current literature, but the precise mechanism is poorly understood. This study aims to investigate the effect of total prostate volume on total glandular tissue volume of the peripheral zone via a novel combination of magnetic resonance imaging (MRI) and histo-anatomical imaging. METHODS: 42 male patients between ages 53-79 years underwent both radical prostatectomy and pre-operative MRI scans. Prostate sizes ranged from 14.8-133.3cc. Quantitative measurements of surgical capsule thickness and glandular epithelial cell density within the peripheral zone (PZ) were obtained on histo-anatomical slides using computer-based imaging software. Quantitative prostatic zonal measurements were obtained from MRI scans. Combining MRI- and histopathology-obtained parameters allowed measurement of the total glandular tissue volume of the PZ (GVPZ). Statistical analysis was performed to identify associations between total prostate volume (TPV) and GVPZ. RESULTS: The Mann-Whitney U-test showed significant decreases in GVPZ in larger prostates when compared to smaller prostates. CONCLUSIONS: Combined MRI and histopathology techniques provide a novel method for accurate measuring of glandular tissue content within the prostatic PZ. The findings of this pilot study support the hypothesis of PZ compression by an expanding transition zone in large BPH prostates, leading to atrophy of PZ glandular tissue. As the majority of PCa originates in the PZ, this dynamic process may explain the protective effect of large BPH prostates against PCa development.

Association Between Prostate Size and MRI Determined Quantitative Prostate Zonal Measurements.

Purpose: Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are the two most prevalent and common urologic diseases impacting elderly men. The current literature has well documented an inverse relationship between prostate/BPH-size and incidence of PCa, but the exact interaction between these two disease entities is not well understood. The purpose of this study is to analyze prostatic zonal measurements with magnetic resonance imaging (MRI) in order to investigate the dynamic changes of the transition zone (TZ) and peripheral zone (PZ) in response to prostate/BPH growth. Methods: Multiparametric magnetic resonance imaging (mpMRI) scans of 430 consecutive male patients aged 18-89 years were obtained to measure the different zonal areas of the prostate. The data were statistically analyzed to identify specific associations between the different measurement parameters and total prostate volume (TPV). Results: The Mann-Whitney U-test showed a significant decline of the average peripheral zone thickness (PZT) (z = -4.5665, p < 0.0001) in larger prostates when compared to smaller prostates. The Spearman correlation between TPV and PZT demonstrated a significant negative correlation (-0.20, p < 0.0001). Conclusion: The data revealed that PZT was significantly smaller in the subgroup of patients with higher TPV. This supports the hypothesis of PZ compression and thinning caused by the growing and expanding TZ in BPH prostates. This dynamic growth-related process in the different prostatic zones may explain the protective effect of BPH against PCa.

Quantitative measurements of prostatic zones by MRI and their dependence on prostate size: possible clinical implications in prostate cancer.

AIM: Many studies support an inverse relationship between benign prostate hypertrophy (BPH) size and incidence of prostate cancer (PCa), but the causal link between these conditions is poorly understood. Recent studies suggest that a growing transition zone (TZ) in the prostate may induce pressure on the outer peripheral zone (PZ), leading to atrophy of the glandular tissue where PCa often originates, providing a possible explanation for this interaction. To further investigate this phenomenon, our pilot study uses magnetic resonance imaging (MRI) to examine quantitative zonal changes in a consecutive cohort of prostates. METHODS: MRI scans of male patients [n = 204, 61.57 ± 13.90 years, average body mass index (BMI) 29.05 kg/m2] with various prostate sizes were analyzed statistically to identify possible associations between prostate parameters, such as total prostate volume (TPV) and peripheral zone thickness (PZT). RESULTS: TPV and PZT demonstrated a weak, inverse correlation (r = -0.21, p = 0.002). However, when examining the plotted data, the relationship between TPV and PZT was significantly different when the cohort was divided into two groups; lower TPV: ⩽87.5 ml (n = 188, TPV x- = 36.01 ± 18.18 ml), and higher TPV: >87.5 ml (n = 17, TPV x- = 125.69 ± 41.13 ml). Average PZT differed significantly between these groups (z = -3.5554, p = 0.0004). CONCLUSIONS: PZT was significantly different for patients with lower versus higher TPVs, suggesting that, above a certain point of BPH growth, the PZ is unable to withstand pressure from an expanding TZ, supporting the notion that growing BPH causes compression of the PZ glandular tissue, and, therefore, BPH may be protective against PCa.

Visceral artery embolization after endoscopic injection of Enteryx for gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) can be difficult to manage medically and may require endoscopic or surgical interventions. The Enteryx procedure was designed to enhance the gastroesophageal barrier function by endoscopic injection of a copolymer into the lower esophageal sphincter. We present a rare case of a patient who was found to have migration of the copolymer into the celiac trunk and bilateral renal arteries during a work-up for persistent intermittent hematuria, which began shortly after Enteryx therapy for GERD.

Venous thromboembolism: deep venous thrombosis and pulmonary embolism in a neurosurgical population.

OBJECT: Venous thromboembolism (VTE), a combination of deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major cause of morbidity and death in neurosurgical patients. This study evaluates 1) the risk of developing lower-extremity DVT following a neurosurgical procedure; 2) the timing of initiation of pharmacological DVT prophylaxis upon the occurrence of VTE; and 3) the relationship between DVT and PE as related to VTE prophylaxis in neurosurgical patients. METHODS: The records of all neurosurgical patients between January 2006 and December 2008 (2638 total) were reviewed for clinical documentation of VTE. As part of a quality improvement initiative, a subgroup of 1638 patients was studied during the implementation of pharmacological prophylaxis. A high-risk group of 555 neurosurgical patients in the intensive care unit underwent surveillance venous lower-extremity duplex ultrasonography studies twice weekly. All patients throughout the review received mechanical DVT prophylaxis. Pharmacological DVT prophylaxis, consisting of 5000 U of subcutaneous heparin twice daily (initially started within 48 hours of a neurosurgical procedure and subsequently within 24 hours of a procedure) was implemented in combination with mechanical prophylaxis. The DVT and PE rates were calculated for each group. RESULTS: In the surveillance group (555 patients), 84% of the DVTs occurred within 1 week and 92% within 2 weeks of a neurosurgical procedure. There was a linear correlation between the duration of surgery and DVT development. The use of subcutaneous heparin reduced the rate of DVT from 16% to 9% when medication was given at either 24 or 48 hours postoperatively, without any increase in hemorrhagic complications. In the overall group (2638 patients), there were 94 patients who exhibited clinical signs of a possible PE and therefore underwent spiral CT; 22 of these patients (0.8%) had radiological confirmation of PE. There was no correlation between the use of pharmacological prophylaxis at either time point and the occurrence of PE, despite a 43% reduction in the lower-extremity DVT rate with pharmacological intervention. CONCLUSIONS: The majority of DVTs occurred within the first week after a neurosurgical procedure. There was a linear correlation between the duration of surgery and DVT occurrence. Use of early subcutaneous heparin (at either 24 or 48 hours) was associated with a 43% reduction of developing a lower-extremity DVT, without an increase in surgical site hemorrhage. There was no association of pharmacological prophylaxis with overall PE occurrence.