Clayton Trimmer - Academia.edu (original) (raw)

Papers by Clayton Trimmer

The Journal of urology, Jan 3, 2015

Current RFA series do not distinguish renal cell carcinoma (RCC) subtypes when reporting oncologi... more Current RFA series do not distinguish renal cell carcinoma (RCC) subtypes when reporting oncologic efficacy. Papillary neoplasms may be more amenable to radiofrequency ablation (RFA) than clear cell carcinoma because they are less vascular which may limit heat energy loss. We report the long-term outcomes of patients treated with radiofrequency ablation for small renal masses (SRM) by RCC subtypes. Patients undergoing RFA for SRM (cT1a) at two institutions from March 2007-July 2012 were retrospectively reviewed. Patients were included if they had biopsy confirmed clear cell or papillary RCC histology. Patients had at least one contrast enhanced cross-sectional image following RFA. Demographic data between tumor subtypes were compared using the paired t-test. Oncologic outcomes were determined using Kaplan-Meier survival analysis, and survivor curves were compared using the log rank test. 229 patients met inclusion criteria. There were 181 clear cell tumors and 48 papillary tumors. M...

Journal of vascular surgery, 2006

Computed tomographic angiography (CTA) has the potential to detect unsuspected extravascular path... more Computed tomographic angiography (CTA) has the potential to detect unsuspected extravascular pathology in patients with vascular disease. The purpose of this study was to determine the prevalence of unexpected findings, additional associated costs, and alterations in treatment in vascular patients undergoing CTA. During a recent 15-month period, 350 subjects (207 men, 143 women; mean age of 66 +/- 14 years) underwent CTA for evaluation of aortic aneurysms (43%), lower extremity occlusive disease (33%), renal artery disease (17%), or aortic graft infection (7%). Unexpected CTA findings were categorized as incidental, clinically important but probably benign, or possibly serious. Medical records were reviewed to determine the outcome of additional testing and to identify alterations in treatment plans. Of the 163 subjects (47%) with positive findings, 95 (27%) were categorized as incidental, 27 (8%) as probably benign, and 41 (12%) as potentially serious. Additional tests were require...

Transcatheter Embolization and Therapy, 2009

• Due to disruption of the pelvic ring due to blunt trauma. Types of pelvic fractures are as foll... more • Due to disruption of the pelvic ring due to blunt trauma. Types of pelvic fractures are as follows: • Lateral compression—causes vertical compression fracture in sacrum and oblique fractures of the pubic rami anteriorly. • Anterior–posterior—opens the pelvis with rotation of iliac wings outward and disruption of pubic symphysis and sacral-iliac joints. • Vertical shear—moves one hemi-pelvis superiorly, tearing the SI joint. • Combination—mixed features of any of above, usually in much more severe trauma.

Urology, 2015

To assess the predictive performance of a modified RENAL nephrometry score for renal tumors under... more To assess the predictive performance of a modified RENAL nephrometry score for renal tumors undergoing radiofrequency ablation (RFA). Patients who underwent RFA were identified from 2002 to 2011, and RENAL nephrometry scoring was performed for each. A modified RENAL (m-RENAL) nephrometry score was created to account for the small sizes of tumors ablated for which the size variable, R, was adjusted. A size of 3 cm was calculated as the optimal cutoff for the R component of the m-RENAL nephrometry score, and tumors were given an R score of 1 if &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3 cm, 2 if 3-4 cm, or 3 if &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;4 cm. Other RENAL variables were unchanged. Oncologic outcomes were stratified by complexity tertiles defined as low (4-6), medium (7-9), and high (10-12). Outcomes were reported as initial ablation success (IAS), recurrence-free survival (RFS), and metastatic-free survival (MFS). The Kaplan-Meir method was used to estimate survival based on complexity tertile. Two hundred forty patients were identified who underwent RFA, of which 192 patients were eligible for analysis. Median follow-up was 32.2 months, and median tumor size was 2.4 cm. IAS was achieved in 185 of 192 patients (96.4%). Overall, the estimated 3-year RFS was 95.1% and MFS was 97.3%. There was no statistical difference between complexity tertiles using the standard RENAL nephrometry score; however, the m-RENAL nephrometry score was significantly associated with IAS and RFS (P = .027 and P = .003, respectively). There were too few events (n = 3) to perform statistical analysis for MFS. A modification to the size variable increases the performance of the RENAL nephrometry score when used to stratify RFA ablation success.

Urology, 2012

To review our 10-year experience with radiofrequency ablation, focusing on the outcomes for the i... more To review our 10-year experience with radiofrequency ablation, focusing on the outcomes for the incidental benign renal tumor. Tumor ablation is an alternative minimally invasive approach for the treatment of small renal masses (SRMs), with published series appropriately emphasizing the outcomes for the renal cell carcinoma subset of treated tumors. However, just as with partial nephrectomy, approximately 20% of SRMs are benign. The intermediate- to long-term outcome of the incidentally ablated benign tumor and its appropriate follow-up protocol is unknown. All SRMs treated with temperature-based radiofrequency ablation from 2001 to 2011 were reviewed. Of a total of 280 enhancing SRMs biopsied at radiofrequency ablation, 47 were confirmed as benign tumors. Ablation success was defined as the lack of enhancement on the initial postablation axial imaging. Recurrence was defined as tumor growth and enhancement on follow-up axial imaging. Of the 47 benign tumors, 32 were treated percutaneously and 15 laparoscopically. The histologic biopsy finding was angiomyolipoma in 10 and oncocytoma in 37. The median tumor size was 2 cm (range 1-3.6), and the mean follow-up was 45 months. No recurrences developed, and all lesions required only 1 treatment session. The median pre- and postoperative glomerular filtration rate was 77 mL/min/1.73 m(2) (range 39-137) and 68 mL/min/1.73 m(2) (range 36-137). The present study was limited by its retrospective nature and small sample population. Radiofrequency ablation of SRMs &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3.5 cm found to be benign on concurrent biopsy can be efficaciously treated with a single treatment session. Long-term follow-up imaging might not be required if successful ablation is determined at the initial post-treatment cross-sectional imaging study.

Urology, 2005

Objectives. To present our experience using radiofrequency ablation (RFA) for the treatment of sm... more Objectives. To present our experience using radiofrequency ablation (RFA) for the treatment of small renal tumors. Our objective was to assess the short-term (1 to 3 years) oncologic efficacy of RFA. Methods. Consecutive renal tumors treated since May 2001 with a minimal follow-up of 6 months were included. Patients were treated with a temperature-based radiofrequency generator and were followed up with serial imaging at 6 weeks, 3 and 6 months, and every 6 months thereafter. Results. A total of 109 small renal tumors (91 patients) were treated with computed tomography-guided percutaneous RFA (n ϭ 63) or laparoscopic RFA (n ϭ 46). The mean tumor size was 2.4 cm (range 0.8 to 4.7). The initial ablation was successful in 107 (98%) of 109 tumors. The two incomplete ablations were successfully re-ablated. Of the 60 patients with at least 1 year of follow-up, 60% had biopsy proven renal cell carcinoma (an additional 24% had no tissue diagnosis). In this group, one local recurrence (1.7%) was detected during a mean follow-up of 19.4 months (range 12 to 33), and in those with known renal cell carcinoma, none had evidence of distant progression (0%). The local recurrence was successfully re-ablated such that all 109 cases had no clinical or radiographic evidence of disease at last follow-up. Three patients died of causes unrelated to cancer. Conclusions. The results of our study have shown that in the short term, RFA appears to be a reasonable therapeutic nephron-sparing approach for treating select patients with small renal tumors. The cancer control appears adequate to date, but longer follow-up is necessary before widespread application. UROLOGY 65: 877-881, 2005.

Journal of Vascular Surgery, 2012

Objective: The goal of the study was to determine the blood pressure (BP) response to renal arter... more Objective: The goal of the study was to determine the blood pressure (BP) response to renal artery stenting (RAS) for patients with hypertension urgency, hypertension emergency, and angina with congestive heart failure (angina/ congestive heart failure [CHF]). Methods: Patients who underwent RAS for hypertension emergencies (n ‫؍‬ 13), hypertension urgencies (n ‫؍‬ 25), and angina/CHF (n ‫؍‬ 14) were included in the analysis. By convention, hypertension urgency was defined by a sustained systolic BP > 180 mm Hg or diastolic BP > 120 mm Hg, while the definition of hypertension emergency required the same BP parameters plus hypertension-related symptoms prompting hospitalization. Patient-specific response to RAS was defined according to modified American Heart Association reporting guidelines. Results: The study cohort of 52 patients had a median age of 66 years (interquartile range 58-72). The BP response to RAS varied significantly according to the indication for RAS. Hypertension emergency provided the highest BP response rate (85%), while the response rate was significantly lower for hypertension urgency (52%) and angina/CHF (7%; P ‫؍‬ .03). Only 1 of 14 patients with angina/CHF was a BP responder. Multivariate analysis showed that hypertension urgency or emergency were not independent predictors of BP response to RAS. Instead, the only independent predictor of a favorable BP response was the number of preoperative antihypertensive medications (odds ratio 7.5; 95% confidence interval 2.5-22.9; P ‫؍‬ .0004), which is another indicator of the severity of hypertension. Angina/CHF was an independent predictor of failure to respond to RAS (odds ratio 118.6; 95% confidence interval 2.8-999.9; P ‫؍‬ .013). Conclusions: Hypertension urgency and emergency are clinical manifestations of severe hypertension, but the number of preoperative antihypertensive medications proved to be a better predictor of a favorable BP response to RAS. In contrast, angina/CHF was a predictor of failure to respond to stenting, providing further evidence against the practice of incidental stenting during coronary interventions. ( J Vasc Surg 2012;55:413-20.)

Journal of Vascular Surgery, 2011

The purpose of the current study was to identify clinical and kidney morphologic features that pr... more The purpose of the current study was to identify clinical and kidney morphologic features that predict a favorable blood pressure (BP) response to renal artery stenting (RAS). Methods: The study cohort consisted of 149 patients who underwent primary RAS over 9 years. Patients were categorized as "responders" based on modified American Heart Association guidelines: BP <160/90 mm Hg on fewer antihypertensive medications or diastolic BP <90 mm Hg on the same medications. All other patients were deemed "nonresponders." Renal volume was estimated as kidney length ؋ width ؋ depth/2 based on preoperative computed tomography or magnetic resonance scans. Median follow-up was 19 months (interquartile range [IQR] 10.0-29.5 months). Results: The median age of the cohort was 68 years (IQR, 60-74 years). A favorable BP response was observed in 50 of 149 patients (34%). Multivariate analysis identified three independent predictors of a positive BP response: (1) requirement for four or more medications (odds ratio, 29.9; P ‫؍‬ .0001), (2) preoperative diastolic BP >90 mm Hg (OR, 31.4; P ‫؍‬ .0011), and (3) preoperative clonidine use (OR, 7.3; P ‫؍‬ .029). The BP response rate varied significantly based on the number of predictors present per patient (P < .0001). Among patients with three-drug hypertension, a larger ipsilateral kidney (volume >150 cm 3 ) increased the BP response rate more than threefold compared with patients with smaller kidneys (63% vs 18% BP response rate; P ‫؍‬ .018).

Journal of Vascular Surgery, 2010

Journal of Vascular Surgery, 2009

The peri-operative use of antiplatelet, anticoagulant and other drugs for patients undergoing car... more The peri-operative use of antiplatelet, anticoagulant and other drugs for patients undergoing carotid endarterectomy (CEA) is unclear and consensus is lacking. This study aimed to assess the current practice of European vascular surgeons with respect to antiplatelet and other medications.

Journal of Vascular Surgery, 2006

Objective: Computed tomographic angiography (CTA) has the potential to detect unsuspected extrava... more Objective: Computed tomographic angiography (CTA) has the potential to detect unsuspected extravascular pathology in patients with vascular disease. The purpose of this study was to determine the prevalence of unexpected findings, additional associated costs, and alterations in treatment in vascular patients undergoing CTA. Methods: During a recent 15-month period, 350 subjects (207 men, 143 women; mean age of 66 ؎ 14 years) underwent CTA for evaluation of aortic aneurysms (43%), lower extremity occlusive disease (33%), renal artery disease (17%), or aortic graft infection (7%). Unexpected CTA findings were categorized as incidental, clinically important but probably benign, or possibly serious. Medical records were reviewed to determine the outcome of additional testing and to identify alterations in treatment plans. Results: Of the 163 subjects (47%) with positive findings, 95 (27%) were categorized as incidental, 27 (8%) as probably benign, and 41 (12%) as potentially serious. Additional tests were required in 57 subjects (15%) to confirm these results. Seventeen (5%) of the 350 original subjects were ultimately considered to have life-threatening pathology found on CTA, but 11 of these were lost to follow-up. Significant alterations in treatment plan occurred in the six patients with life-threatening pathology and in one other patient with benign disease. Conclusions: These data suggest that unexpected CTA findings are common in vascular patients. Although few prove to be serious, treatment delays associated with evaluation of benign lesions are modest. Of major concern, one fourth of patients with potentially serious lesions did not undergo further evaluation in this study. Vascular surgeons need to ensure adequate follow-up for their patients with potentially serious extravascular lesions. ( J Vasc Surg 2006;44:998-1001.)

Journal of Vascular and Interventional Radiology, 2010

Journal of Vascular and Interventional Radiology, 2009

The Journal of Urology, 2012

Renal tumor size influences the efficacy of radio frequency ablation but identification of confid... more Renal tumor size influences the efficacy of radio frequency ablation but identification of confident size cutoffs has been limited by small numbers and short followup. We evaluated tumor size related outcomes after radio frequency ablation for patients with adequate (greater than 3 years) followup. We identified 159 tumors treated with radio frequency ablation as primary treatment. Disease-free survival was defined as the time from definitive treatment to local recurrence, detection of metastasis or the most recent imaging showing no evidence of disease. Patients were evaluated with contrast enhancing imaging preoperatively, and at 6 weeks, 6 months and at least annually thereafter. Median tumor size was 2.4 cm (range 0.9 to 5.4) with a median followup of 54 months (range 1.5 to 120). Renal cell carcinoma was confirmed in 72% of the 150 tumors that had pre-ablation biopsy (94%). The 3 and 5-year disease-free survival was comparable at 92% and 91% overall, and was dependent on tumor size, being 96% and 95% for tumors smaller than 3.0 cm and 79% and 79%, respectively, for tumors 3 cm or larger (p=0.001). Most failures (14 of 18) were local, either incomplete ablations or local recurrences. This is an intent to treat analysis and, therefore, includes patients ultimately found to have benign tumors, although outcomes were comparable in patients with cancer. Radio frequency ablation treatment success of the small renal mass is strongly correlated with tumor size. Radio frequency ablation provides excellent and durable outcomes, particularly in tumors smaller than 3 cm. Of tumors 3 cm or larger, approximately 20% will recur such that alternative treatment techniques should be considered. However, most treatment failures are local and are often successfully treated with another ablation session.

The Journal of Urology, 2010

INTRODUCTION AND OBJECTIVES: Long-term oncologic outcomes for renal thermal ablation are limited.... more INTRODUCTION AND OBJECTIVES: Long-term oncologic outcomes for renal thermal ablation are limited. We present our experience with radiofrequency ablation (RFA) therapy for 243 small renal masses (SRMs) over the past 7.5 years.

The Journal of Trauma: Injury, Infection, and Critical Care, 2010

To report our experience with the diagnosis and treatment of aortoiliac vascular injuries caused ... more To report our experience with the diagnosis and treatment of aortoiliac vascular injuries caused by misplaced orthopedic fixation screws. Six patients (age range, 35-60 years; mean, 52 years) were diagnosed with seven arterial injuries related to misplacement of fixation screws. The location of the injuries were thoracic aorta (n = 4) and common iliac arteries (n = 3). There was vessel wall penetration in five injuries resulting in active bleeding in two patients, contained penetrations in two patients, and vessel occlusion in one patient. One patient had associated inferior vena cava injury and pulmonary embolism. Two patients had asymptomatic impingement of the aortic wall by the screws. Vascular injuries resulted in death in one patient and limb amputation in another patient. Three patients were treated with placement of stent grafts and screw removal. Screw replacement was performed in one patient. Conservative observation was done in one patient. Vascular injuries related to misplacement of fixation screws are relatively infrequent but potential life and limb-threatening complications that require early recognition with prompt repair of vascular lesions and screw reposition.

Journal of Endourology, 2007

Most patients have minimal pain after percutaneous radiofrequency ablation (RFA) of a renal tumor... more Most patients have minimal pain after percutaneous radiofrequency ablation (RFA) of a renal tumor. However, anecdotally, there is some variation in the amount of patient discomfort. Our goal was to identify relevant patient factors and characteristics of their renal tumors that may influence pain after percutaneous RF ablation. We performed a retrospective chart review of 59 sequential patients who received percutaneous RFA between 2001 and 2005 at a single institution. Data on patient age, sex, body mass index (BMI), and narcotic administration in the periprocedural period were available for 46 patients. Preoperative imaging (CT or MRI) was reviewed to determine tumor size and location, as well as the shortest distance of the mass to the body-wall musculature. The distance from the renal mass to the body-wall musculature was significantly correlated with the total narcotics received in the periprocedural period. This measured distance did not correlate with the patient&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s BMI. No other relations between patient factors or tumor characteristics and peri-procedural narcotic usage were identified. Patients whose tumors lie close to their body-wall musculature have greater narcotic requirements in the periprocedural period. Knowledge of this correlation should result in better patient counseling and help anticipate periprocedural analgesia requirements.

Journal of Endourology, 2013

Objective: To report one of the largest series of clinical and renal function outcomes of treated... more Objective: To report one of the largest series of clinical and renal function outcomes of treated iatrogenic vascular lesions (IVL) following partial nephrectomy (PN). Angioembolization (AE) is the treatment of choice for these lesions, but the additional renal injury conferred by this treatment has not been well described. Subjects/Patients: Patients that underwent open (OPN), laparoscopic (LPN) or robotic partial nephrectomy (RPN) from 2002-2012 were identified and those with AE were selected. Patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; charts were reviewed and renal function was analyzed using estimated GFR (eGFR) and progression of chronic kidney disease (CKD) classification before and after PN and AE. Results: 849 patients underwent PN and 28 (3.3%) developed an IVL. 20 (71%) presented with gross hematuria at a mean of 10.2 ± 7.7 days after PN and eight (28%) required transfusion. All patients had identifiable IVL at the time of selective AE and technical success was achieved in 24/28 (86%) although 4 required subsequent additional AE. The paired decrease in eGFR after PN was significant (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.01), while the paired change in eGFR after AE was not either with short-term (2.8 days) or intermediate-term (362 days) follow-up (p=0.50). Four patients experienced transient worsening in CKD classification after AE, although 3 experienced CKD stage improvement. Conclusion: Selective angioembolization for iatrogenic vascular lesions following partial nephrectomy is safe, efficacious and does not lead to a significant impairment of renal function. It remains the preferred approach for the evaluation and management of post-partial nephrectomy hemorrhage.

The Journal of Clinical Endocrinology & Metabolism, 2007

In primary aldosteronism, elevated serum 18-hydroxycorticosterone (18OHB) suggests aldosterone-pr... more In primary aldosteronism, elevated serum 18-hydroxycorticosterone (18OHB) suggests aldosterone-producing adenoma (APA) rather than bilateral, idiopathic hyperaldosteronism (IHA), but little is known about the relative production of 18OHB and aldosterone (A) in APAs compared with IHA. We measured 18OHB, A, and cortisol (F) in blood from adrenal vein sampling (AVS) studies. We compared the discriminatory power of gradients in 18OHB/A and 18OHB/F ratios with A/F ratio gradients for distinguishing APA from IHA. We measured 18OHB and A in excess serum from 23 AVS studies performed at our university hospitals. We calculated the ratios 18OHB/A, 18OHB/F, and A/F for all specimens, and determined the adrenal vein gradients for these ratios. The 18OHB/A ratios were much lower in blood draining APAs (2.17 +/- 0.62) than in blood draining the contralateral adrenals (12.96 +/- 12.76; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) but similar to blood draining IHA adrenals (4.69 +/- 4.32; P = 0.02). In contrast, the 18OHB/F ratios were elevated in specimens from APAs (26.03 +/- 11.51) compared with IHA adrenals (9.22 +/- 5.18; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) or the contralateral adrenals (6.23 +/- 2.97; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Using 18OHB/F gradient greater than two or 18OHB/A gradient less than 0.5 as criteria for lateralization, interpretations agreed with lateralizations based on A/F gradients in 21 of 23 cases. High serum 18OHB in APA reflects augmented production of both 18OHB and A, not disproportionate 18OHB secretion relative to A. The 18OHB/A and 18OHB/F gradients are useful adjuncts but not as reliable as A/F gradients for A lateralization during AVS.