Utilization of Re-VASC, the Novel Retroperitoneal Neovascularity Scoring System, for Characterization of T1a Small Renal Masses.

Purpose: Early characterization of small (T1a, <4 cm) renal masses is imperative for patient care and treatment planning. Renal biopsy is a sensitive and specific procedure that can accurately differentiate small renal masses as malignant or benign. However, it is an invasive procedure with a nonnegligible complication rate and is not performed routinely at most institutions. In this study, we sought to apply the Retroperitoneal Vascularity Assessment and Scoring in Carcinoma (Re-VASC) scoring system to T1a renal masses and analyzed whether it could differentiate these masses as benign or malignant. Methods: We obtained Institutional Review Board approval to retrospectively examine the records of all patients who presented to our single, urban academic referral center for surgical treatment of renal cell carcinoma (RCC). For the malignant group, patients with a diagnosis of T1a RCC from pathologic evaluation were included. Additionally, patients with a histopathological diagnosis of a T1a nonmalignant renal mass (fat poor-angiomyolipoma or oncocytoma) were included in our benign group. Results: This study includes 57 benign and 69 malignant T1a renal tumors. Average size for benign and malignant masses were 2.47 and 2.63, respectively (p = 0.267). Analysis demonstrated no significant difference between both groups in terms of sex, laterality, or size. The average Re-VASC score of benign and malignant masses was 0.175 and malignant masses was 0.784, respectively (p < 0.001). Additionally, the Re-VASC score was independently associated with malignancy with an odds ratio of 2.223 (p = 0.0109). Conclusion: The Re-VASC scoring system exhibits significantly greater values for malignant T1a renal masses when compared to benign masses. As a result, it shows promise as an adjunctive tool to renal biopsy for clinical decision-making. Further assessment of Re-VASC's true efficacy as a diagnostic marker will include prospective evaluation of a larger multicenter population.

Evaluation of Renal Function and Stent Durability Following Resonance Stent Placement for Benign Disease.

Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time.

A Review of the Recommendations and Strength of Evidence for Clinical Practice Guidelines on the Management of Small Renal Masses.

Introduction: With the rise in the detection of incidental small renal masses (SRM), the management paradigm for these patients has become an issue of increasing concern. We aim to identify areas of consensus, controversy, and opportunities for improvement among recently published guidelines and assess the strength of evidence for the management of SRMs. Methods: We reviewed practice guidelines for SRMs promulgated by the American Urological Association, European Association of Urology, National Comprehensive Cancer Network, American Society of Clinical Oncology, European Society for Medical Oncology, and the Chinese Society of Clinical Oncology. Levels of evidence and strength of recommendations for evaluation, management and follow-up were analyzed with regard to consensus, conflict, and neglect. Results: There is consensus among guidelines for the initial evaluation and treatment of SRMs; however, discrepancies exist with regard to indications for active surveillance, thermal ablation, and timing/method of follow-up after treatment. Routine renal mass biopsy is not recommended by any guideline. Overwhelmingly, guideline statements are based on low to moderate levels of evidence; only 23% of the reviewed guidelines were based on high-level evidence, 38% based on moderate-level, and 39% on low-level evidence or expert opinion. Conclusions: Despite all six guidelines sharing a consensus on most management topics regarding SRMs, the ongoing lack of high-level evidence precludes gold standard recommendations in the areas of diagnosis, treatment, and follow-up. More high-quality studies are needed to develop a stronger, data-supported universal guideline for the management of SRMs.

Porcine Bladder Replacement with a Bilayer Silk Fibroin Enhanced Prosthetic Reservoir: A Feasibility Study.

Introduction: The creation of synthetic reservoirs for bladder replacement has been limited by challenges of interfacing synthetic materials and native tissue. We sought to overcome this challenge by utilizing a novel bilayer silk fibroin scaffold (BLSF) as an intermediary toward the development of an acellular prosthetic reservoir. Methods: Under institutionally approved protocols, 3D-printed reservoirs were implanted in six juvenile female pigs after cystectomy. BLSF was attached to the in situ prosthetic reservoir serving as an intermediary to native ureteral and urethral tissue anastomoses. Our first protocol allowed four pigs to be survived up to 7 days, and the second protocol allowed two pigs to be survived for up to 1 year. At the first sign of functional decline or the end of the study period, the animals were euthanized, and kidneys, ureters, prosthetic bladder, and urethra were harvested en bloc for histopathology analysis. Results: The first two pigs had anastomotic urine leaks because of design flaws resulting in early termination. The third pig had acute renal failure resulting in early termination. The artificial bladder design was modified in subsequent iterations. The fourth pig survived for 7 days and, upon autopsy, had intact urethral and ureteral anastomoses. The fifth and sixth pigs survived for 11 and 12 weeks, respectively, before they were sacrificed because of failure to thrive. One animal developed an enteric fistula. The other animal had an intact anastomosis, and the BLFS was identified at the ureteral and urethral anastomoses on histopathologic analysis. Conclusions: Replacing the porcine bladder with a prosthetic bladder was achieved for up to 3 months, the second longest survival period for a nonbiologic bladder alternative. BLSF was used for the first time to create an interface between synthetic material and biologic tissue by allowing ingrowth of urothelium onto the acellular alloplastic bladder.

Novel Retroperitoneal Neovascularity Scoring System in Renal Cell Carcinoma Tumor Staging.

Purpose: Renal cell carcinoma (RCC) is the most common type of kidney cancer worldwide. Although radiologists assess enhancement patterns of renal tumors to predict tumor pathology report, to our knowledge, no formal scoring system has been created and validated to assess the level of neovascularity in RCC, despite its critical role in cancer metastases. In this study, we characterized and analyzed the level of angiogenesis in tumor-burdened kidneys and their benign counterparts. We then created and validated a scoring scale for neovascularity that can help predict tumor staging for RCC. Methods: After Institutional Review Board approval, the charts of patients who had undergone operation for RCC between January 13, 2014 and February 4, 2020 were retrospectively reviewed for inclusion in this study. Inclusion criteria were a diagnosis of RCC, simple/radical nephrectomy, preoperative contrast-enhanced CT scans, and complete pathology reports. Neovascularity was scored on a scale of 0-4 where 0 = no neovascularity detected, 1 = a single vessel <3 mm wide, 2 = a single vessel ≥3 mm wide, 3 = multiple vessels <3 mm wide, and 4 = multiple vessels ≥3 mm wide. Results: A total of 227 patients were included in this study. Most of the tumor pathology reports were clear cell carcinoma, regardless of tumor staging. The average neovascularity score was 1.07 for pT1x tumors, 2.83 for pT2x tumors, and 3.04 for pT3x tumors. There was a significant difference in neovascularity score between pT1x and pT2x tumors (p = 0.0046), pT1x and pT3x tumors (p < 0.0001), and benign kidneys and kidneys with RCC (p < 0.0001). Conclusion: Our novel vascular scoring system for RCC demonstrates significant correlation with RCC pathological tumor staging. This scoring system may be utilized as part of a comprehensive radiological assessment of renal tumors, potentially improving tumor characterization and clinical decision making.

Beyond Efficiency: Surface Electromyography Enables Further Insights into the Surgical Movements of Urologists.

Introduction: Surgical skill evaluation while performing minimally invasive surgeries is a highly complex task. It is important to objectively assess an individual's technical skills throughout surgical training to monitor progress and to intervene when skills are not commensurate with the year of training. The miniaturization of wireless wearable platforms integrated with sensor technology has made it possible to noninvasively assess muscle activations and movement variability during performance of minimally invasive surgical tasks. Our objective was to use electromyography (EMG) to deconstruct the motions of a surgeon during robotic suturing (RS) and distinguish quantifiable movements that characterize the skill of an experienced expert urologic surgeon from trainees. Methods: Three skill groups of participants, novice (n = 11), intermediate (n = 12), and expert (n = 3), were enrolled in the study. A total of 12 wireless wearable sensors consisting of surface EMGs and accelerometers were placed along upper extremity muscles to assess muscle activations and movement variability, respectively. Participants then performed a RS task. Results: EMG-based parameters, total time, dominant frequency, and cumulative muscular workload, were significantly different across the three skill groups. We also found nonlinear movement variability parameters such as correlation dimension, Lyapunov exponent trended differently across the three skill groups. Conclusions: These findings suggest that economy of motion variables and nonlinear movement variabilities are affected by surgical experience level. Wearable sensor signal analysis could make it possible to objectively evaluate surgical skill level periodically throughout the residency training experience. Clinical Trial Registration Number: HS# 2018-4407.

Prospective, Randomized Comparison of Dual-Lumen vs Single-Lumen Flexible Ureteroscopes in Proximal Ureteral and Renal Stone Management.

Introduction: We sought to compare the safety, efficacy, efficiency, and surgeon experience during upper urinary tract stone management with single-lumen (SLFU) vs dual-lumen flexible ureteroscopes (DLFU). Materials and Methods: Seventy-nine patients with proximal ureteral or renal stone burden <2 cm were randomized to a SLFU or DLFU. We recorded times for ureteroscopy (URS), laser lithotripsy, stone basketing, as well as intraoperative and postoperative complications. The rate of stone clearance and stone free status were calculated using CT imaging. Surgeons completed a survey after each procedure rating various metrics regarding ureteroscope performance. Results: Thirty-five patients from the single-lumen group and 44 patients from the dual-lumen group had comparable median URS time (37 vs 35 minutes, p = 0.984) and basketing time (12 vs 19 minutes; p = 0.584). Median lithotripsy time was decreased in the dual-lumen group (single: 6 vs dual: 2 minutes, p = 0.017). The stone clearance rate was superior in the dual-lumen group (single: 3.7 vs dual: 7.1 mm3/min, p = 0.025). The absolute stone-free rate (SFR) was superior for the dual-lumen group (single: 26% vs dual: 48%, p = 0.045). No differences in intraoperative (single: 0% vs dual: 2%; p = 0.375) and postoperative complications (single: 7% vs dual: 11%, p = 0.474) were observed. Surgeons' ratings of the dual-lumen ureteroscope was superior for visibility, comfort, ease of use, and overall performance. Conclusions: The use of the dual-lumen ureteroscope in patients with renal and proximal ureteral stones <2 cm provided shorter lithotripsy time, higher stone clearance rates, improved SFR, and superior surgeon ratings when compared with SLFUs.

The Impact of One Week of Pre-Stenting on Porcine Ureteral Luminal Circumference.

Objectives: Larger ureteral access sheaths (UASs) have the potential to improve ureteroscopic stone removal outcomes but are often avoided by surgeons because of concerns of ureteral injury. Using our novel UAS force sensor and previously defined force thresholds for ureteral injury, we sought to evaluate the impact of 1 week of stenting on the maximum safe dilation of ureteral luminal circumference. Methods: Twelve juvenile female Yorkshire pigs (24 ureters) were evaluated. The inner (i.e., luminal) circumference of each ureter was determined using Cook urethral dilators ranging from 8F to 24F in 2F increments, 37 cm in length. Each dilator was sequentially passed while applying the UAS force sensor to measure insertion force before and after 1 week of stent placement. Each ureter was randomized to receive either a 4.7F or 7.0F stent (20 cm). Maximum ureteral luminal circumference was defined as effective passage of the dilator to the ureteropelvic junction with ≤6 newtons (N) of force (the force threshold previously defined by porcine and clinical studies to avoid ureteral damage). After passage of the largest dilator at 6 N, flexible ureteroscopy was performed and a post-ureteroscopic lesion scale (PULS) was recorded. Results: After 1 week of stent placement, the median ureteral luminal circumference increased to 15F representing a mean increase of 3.8F ± 2.8F (p < 0.001). Twenty-one (88%) of the pre-stented ureters had an increase in luminal circumference, with 12 ureters (50%) dilated to ≥16F (p = 0.032), 6 ureters (25%) dilated to ≥18F, and in 2 cases a maximum size of 24F was recorded. The PULS grade was ≤2 in all cases, indicating no high-grade ureteral injuries. Laterality and stent size did not impact ureteral luminal circumference after pre-stenting (p = 0.232 and p = 0.337, respectively). Conclusions: One week of ureteral stenting resulted in nearly a 4F increase in the luminal circumference of porcine ureters.

Multidisciplinary Approach and Outcomes of Pretreatment Small (cT1a) Renal Mass Biopsy: Single-Center Experience.

Purpose: We evaluated our experience of a multidisciplinary approach to renal mass biopsy (RMB) for small renal masses (SRMs) employing in-office ultrasound (US)-guided biopsy by urology (24%), CT, or US biopsy by interventional radiology (IR) (79%), and endoscopic ultrasound (EUS)-guided biopsy by gastroenterology (GI) (4%). Materials and Methods: A single-institution retrospective review of patients who underwent RMB for SRM from May 2013 to August 2019 was conducted. Data regarding patient demographics, tumor characteristics, biopsy technique, histopathology, and management were collected. Diagnostic rates, concordance with final pathology, complications, and outcomes were analyzed. Results: Of the 192 biopsies reviewed, 63% biopsies were malignant, 20% were benign, and 17% were nondiagnostic. Based on biopsy results, 71 patients (37%) elected active surveillance. Thirty-eight (20%) patients underwent cryoablation, 56 (29%) underwent partial nephrectomy, 14 (7%) underwent radical nephrectomy, and the remaining patients were treated elsewhere. The rate of surgery for benign pathology after pretreatment RMB was 3%. The concordance rate between biopsy and final pathology was 99% for malignancy, 96% for specific pathology subtype, and 85% for renal cell carcinoma grade. Median time from diagnosis to definitive treatment was 97 days (urology: 76, IR: 110 and GI: 54, p = 0.002). Three (1.6%) Clavien I complications were reported. Conclusion: Our multidisciplinary approach to RMB for clinical stage T1a demonstrated favorable safety and diagnostic rates, which effectively directed management strategies and minimized surgery for benign disease. Urologist-performed office biopsies significantly shortened the time from diagnosis to definitive treatment. Our experience with GI EUS biopsy has demonstrated feasibility and safety for tumors that were otherwise not accessible percutaneously.

Ex Vivo Renal Stone Dusting: Impact of Laser Modality, Ureteral Access Sheath, and Suction on Total Stone Clearance.

Introduction and Objectives: Conventional renal stone dusting is challenging; the holmium (Ho:YAG) laser and holmium with MOSES effect (Ho:YAG-MOSES) fail to uniformly produce fragments ≤100 µm (i.e., dust). The superpulse thulium fiber laser (sTFL) may more effectively render uroliths into "dust," and may thus improve stone-free rates. Accordingly, we performed ex vivo evaluations with all three laser modalities, assessing stone fragments and stone clearance. Methods: Seventy-two ex vivo porcine kidney-ureter models were divided into 12 groups of 6: laser type (Ho:YAG, Ho:YAG-MOSES, sTFL), ureteroscope with and without applied suction, and the presence or absence of a 14F ureteral access sheath (UAS). Calcium oxalate stones were preweighed and implanted into each kidney via a pyelotomy. Stones were treated at 16W using dusting settings of 0.4J × 40Hz (Ho:YAG), 0.2J × 80Hz (Ho:YAG-MOSES), and 0.2J × 80Hz (sTFL) for up to 20 minutes. No stone basketing was performed. Kidneys were bivalved and residual fragments were collected, dried, weighed, and sieved to determine fragment size and stone clearance. Results: Initial stone mass (mg), procedure time (seconds), and laser energy expenditure (kJ) were similar in all 12 groups. The greatest stone clearance was seen with sTFL + suction + UAS (94%) compared with a conventional technique (Ho:YAG + no suction + no UAS) (65%, p < 0.01). The use of sTFL provided greater stone clearance than Ho:YAG or Ho:YAG-MOSES. Aspiration improved stone clearance for sTFL (p = 0.01), but not for Ho:YAG or Ho:YAG-MOSES, consistent with the creation of smaller fragments with sTFL. Presence of a 14F UAS improved stone clearance in all scenarios (p < 0.01). Conclusions: In this ex vivo study, stone clearance was optimized under the following conditions: sTFL, 14F UAS, and aspiration. This combination resulted in 94% of stone fragments being cleared; the 6% remaining fragments were all <2 mm. In all scenarios, deployment of a 14F UAS improved stone clearance.

The use of combination regenerative therapies for erectile dysfunction: rationale and current status.

Erectile Dysfunction (ED) is defined as the inability to achieve and maintain an erection sufficient for sexual intercourse. Available treatments for ED provide only symptomatic relief, which is for the most part temporary. Regenerative therapies such as Low Intensity Shockwave, Platelet-Rich Plasma, and Stem Cell therapy can potentially provide a "cure" for ED by reversing the underlying pathology of ED rather than just treating the symptoms. Low Intensity Shockwave therapy is the most evidence based at this point and is thought to act by improving penile blood flow, repairing previous nerve damage, and activating stem cells. Stem Cell therapy takes advantage of the self-replicative potential of stem cells to create new corporal tissue, but also to recruit host cells and angiogenic factors to stimulate endogenous repair. Platelet-Rich Plasma therapy uses concentrated growth factors that already exist within the bloodstream to repair damaged nerves and increase penile blood flow. The use of combination restorative therapy may provide an additive or synergistic benefit greater than any one therapy alone because of its overlapping mechanisms of action on the penis but is a topic that remains to be studied.

Global Assessments of the Endockscope System: Long-Term Impact of Cyber Endoscopy.

Introduction: The disproportionate costs of state-of-the-art endoscopic equipment prohibit urologists from performing endoscopy in underserved countries. Given the global prevalence of smartphones, we engineered a $45 alternative endoscope utilizing three-dimensional printed attachments, an 8 × lens, and a 1000-lumen light-emitting diode cordless flashlight (Endockscope System [ES]). Materials and Methods: At the 34th World Congress of Endourology in Cape Town, South Africa (WCE 2016; 4-year group), and at the 39th Congress of the Société Internationale d'Urologie (SIU) in Athens, Greece (SIU 2019; 8-month group), a total of 40 ES kits were distributed free of charge to an international group of urologists. Participants were given instructions and a hands-on demonstration of the device. Urologists given an ES were subsequently asked to complete a survey between June and September 2020 that included questions regarding user satisfaction, comfort, and comparability of the ES to standard endoscopic systems. Results: Urologists from 23 countries received ES kits. Overall, 10 of 22 urologists (10/22; 45%) from the 4-year group and 18 of 18 urologists (18/18; 100%) from the 8-month group completed the survey. The ES device was used by 80% (8/10) and 83% (15/18) of urologists from the 4-year and the 8-month groups, respectively. Of note, the greatest impact of ES usage was among urologists from the most impoverished countries. Of those who used the ES, 44% (4/9) of urologists from the 4-year cohort and 47% (8/17) from the 8-month cohort reported they were able to perform more endoscopic procedures directly because of the ES. Moreover, 57% (4/7) of the 4-year participants and 67% (10/15) of the 8-month participants found the ES equal or superior in quality to their standard endoscopic equipment. Conclusion: The ES provided an effective and inexpensive system that enabled urologists in resource-challenged countries to effectively perform and expand their use of urologic endoscopy.

Evaluation of a Novel Female Gender Flexible Ureteroscope: Comparison of Flow and Deflection to a Standard Flexible Ureteroscope.

Introduction: The advent of single-use disposable flexible ureteroscopes allows for rapid prototyping of novel endoscopes. In this regard, we sought to develop a female-specific ureteroscope, with a shorter working length, to account for the female anatomy. We hypothesized that the shorter, female-specific single-use flexible ureteroscope would engender higher irrigation flow at a given pressure than that of the standard-length ureteroscope. Methods: An in vitro analysis of a standard 65 cm Dornier Axis™ ureteroscope and a shorter, 45 cm female-specific Dornier Axis ureteroscope was performed. All other aspects of the endoscopes were identical. Each ureteroscope was oriented vertically and connected to a Thermedx® irrigation system to provide uniform pressurized flow. The average flow rate was computed over five, 2-minute periods at pressure settings of 50, 100, 150, and 200 mm Hg. Data were collected with the working channel unoccupied, after placement of a 200 µm (0.6F) holmium laser fiber and after passage of a 1.7F stone basket. The procedure was then repeated with the endoscopes at maximum deflection. Results: The female gender ureteroscope had significantly higher irrigation flow rates than the standard-length ureteroscope under all conditions by an average of 11% (p < 0.02). The highest average percent increase, 17% (p < 0.001), was seen with the 1.7F NGage® basket in the working channel with the endoscope straight. The maximum angle of deflection was not significantly different between the female gender and standard ureteroscopes with an open working channel (314° vs 315°, p = 0.86), with the 1.7F NGage basket in place (314° vs 315°, p = 0.15), and with the 200 µm holmium laser in place (316° vs 309°, p = 0.09). Conclusions: A 45 cm female gender ureteroscope allows for a higher irrigation flow rate than the standard-length ureteroscope under all test conditions. There is no added benefit with regard to deflection capabilities.

Renal Collecting System Injury During Percutaneous Nephrolithotomy, More Likely When Using Continuous Flow Sheaths?

Background: Renal collecting system injuries are a rare occurrence during percutaneous nephrolithotomy (PCNL). However, when they do happen, the potential for complications rises exponentially the longer the injury goes undetected. This case highlights a possible higher rate of injury when using continuous flow sheaths. Case Presentation: A 65-year-old woman with history of large volume obstructing left-sided renal pelvis stone had an emergent ureteral stent placed for infection and was referred for interval management. Patient was taken for PCNL in the prone split-leg position where a continuous flow ureteral access sheath and a continuous flow nephrostomy sheath was used. Puncture and dilatation were performed under endoscopic guidance to avoid collecting system injury during access. The anesthesiologist discovered abnormalities in the patient's pulmonary ventilation settings. This allowed the surgical team to quickly halt the procedure and place the patient supine where a distended abdomen was discovered consistent with irrigation fluid extravasation into the abdominal cavity. Given concern for abdominal compartment syndrome, interventional radiology was then called to assist in placing a drain in the right lower quadrant of the patient to evacuate the irrigation fluid. This is the second such occurrence in a span of 6 months when using continuous flow ureteral access and nephrostomy sheaths. Conclusion: Renal collecting systems injuries are infrequent when access is obtained under endoscopic guidance. Prompt recognition of physiologic breathing abnormalities allowed the surgical team to quickly treat the injury, preventing further complications from arising in the setting of a diagnosis where time to detection plays an important role in prognosis. However, given that this is the second such injury, the usage of continuous flow sheaths and their rate of associated complications and injuries must be thoroughly examined.

A comparison of readmission and complication rates and charges of inpatient and outpatient multiple-level anterior cervical discectomy and fusion surgeries in the Medicare population.

OBJECTIVE: This study aims to assess the relationship of comorbidities and postoperative complications to rates of readmission for geriatric patients undergoing anterior cervical discectomy and fusion (ACDF) involving more than 2 levels on an inpatient or outpatient basis. With the rising costs of healthcare in the United States, understanding the safety and efficacy of performing common surgical interventions (including ACDF) as outpatient procedures could prove to be of great economic impact.Objective This study aims to assess the effect of comorbidities and postoperative complications on the rates of readmission of geriatric patients undergoing multilevel anterior cervical discectomy and fusion (ACDF) procedures (i.e., ACDF involving 3 or more levels) on an inpatient or outpatient basis. Same-day surgery has been demonstrated to be a safe and cost-effective alternative to the traditional inpatient option for many surgical interventions. With the rising costs of healthcare, understanding the safety and efficacy of performing common surgical interventions as outpatient procedures could prove to be of great economic impact. METHODS: The study population included total of 2492 patients: 2348 inpatients and 144 outpatients having ACDF procedures involving 3 or more levels in the Medicare Standard Analytical Files database. Age, sex, comorbidities, postoperative complications, readmission rates, and surgical procedure charges were compared between both cohorts. For selected variables, logistic regression was used to model odds ratios for various comorbidities against readmission rates for both inpatient and outpatient cohorts. Chi-square tests were also calculated to compare these comorbidities with readmission in each cohort. RESULTS: Overall complication rates within 30 postoperative days were greater for inpatients than for outpatients (44.2% vs 12.5%, p < 0.001). More inpatients developed postoperative urinary tract infection (7.9% vs 0%, p < 0.001), and the inpatient cohort had increased risk of readmission with comorbidities of anemia (OR 1.52, p < 0.001), smoking (OR 2.12, p < 0.001), and BMI ≥ 30 (OR 1.43, p < 0.001). Outpatients had increased risk of readmission with comorbidities of anemia (OR 2.78, p = 0.047), diabetes mellitus type 1 or 2 (OR 3.25, p = 0.033), and BMI ≥ 30 (OR 3.95, p = 0.008). Inpatients also had increased readmission risk with a postoperative complication of surgical site infection (OR 2.38, p < 0.001). The average charges for inpatient multilevel ACDF were significantly higher than for multilevel ACDF performed on an outpatient basis ($12,734.27 vs $12,152.18, p = 0.0019). CONCLUSIONS: This study suggests that ACDF surgery involving 3 or more levels performed as an outpatient procedure in the geriatric population may be associated with lower rates of readmissions, complications, and surgical charges.

Adult intradural intramedullary astrocytomas: a multicenter analysis.

BACKGROUND: Intramedullary tumors constitute approximately 20-30% of all spinal cord tumors and approximately 30-40% of these are astrocytomas. Furthermore, they comprise only about 2-4% of all primary central nervous system (CNS) tumors. Due to their rarity and poor prognosis, large population-based studies are needed to assess the epidemiology and survival risk factors associated with these tumors in the hope of improving outcomes. The authors undertook this retrospective study to explore factors that may influence survival in adult patients with intramedullary astrocytomas. METHODS: Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a prospective cancer registry, the authors retrospectively assessed survival in histologically confirmed, intramedullary spinal cord astrocytomas in patients 18 years of age and older. Survival was described with Kaplan-Meier curves and multivariate regression analysis was used to assess the association of several variables with survival while controlling for confounding variables. RESULTS: Analysis by multivariate regression of 131 cases showed that increasing age of diagnosis [hazard ratio (HR) 1.52, 95% CI: 1.17-1.99, P=0.001], WHO grade IV classification (HR 8.85, 95% CI: 2.83-27.69, P<0.001), tumor invasiveness (HR 2.94, 95% CI: 1.00-8.64, P=0.047), and sub-total resection (HR 5.80, 95% CI: 1.20-28.03, P=0.029) were associated with statistically significant decreases in survival. CONCLUSIONS: This study suggest that older age, higher WHO grade, tumor invasiveness as well as sub-total resection were all associated with a worse prognosis.

Outpatient and Inpatient Readmission Rates of 1- and 2-Level Anterior Cervical Discectomy and Fusion Surgeries.

OBJECTIVE: This study looks at the various comorbidities and postoperative complications and their impact on readmission rates of patients undergoing outpatient versus inpatient 1- and 2-level anterior cervical discectomy and fusion (ACDF). With increasing costs within the United States medical system, one emerging cost-saving strategy is to evolve traditional inpatient procedures into outpatient same-day surgeries. However, patient safety remains a crucial priority. METHODS: A total of 28,427 patients were analyzed, with 26,368 undergoing inpatient ACDF surgery and 2059 undergoing outpatient ACDF surgery. Age, sex, comorbidities, postoperative complications, readmission rates, and overall financial cost were compared between both cohorts. RESULTS: Data from 28,427 one- and two-level ACDF procedures that were split between inpatient and outpatient were collected. Thirty-day readmission rates were significantly lower in outpatients than inpatients (4% vs. 10.1%, P < 0.001). Inpatients had higher rates of urinary tract infection (2.4% vs. 1.4%), deep vein thrombosis (0.6% vs. 0%), and myocardial infarction (0.2% vs. 0%), whereas outpatients had higher rates of pulmonary embolism (7.7% vs. 0.4%). Outpatients had increased readmission risk with comorbidities of diabetes (odds ratio [OR], 48.93; P < 0.001), smoking (OR, 4.6; P < 0.001), body mass index ≥30 (OR, 2392; P < 0.001). The average cost of outpatient surgery was less than that of inpatient surgery ($7774.8 vs. $7956.75, P = 0.0444). CONCLUSION: This study suggests that in the appropriately selected patients, ACDF can safely be performed in an outpatient setting.