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Ronald S Arellano

Publications and source records attributed to Ronald S Arellano.

16 recordsLinked to original sources
PubMed2006

Percutaneous radiofrequency ablation of ovarian cancer metastasis to the liver: indications, outcomes, and role in patient management.

OBJECTIVE: Stages III and IV ovarian cancer are treated with a combination of chemotherapy and resection, in some cases including second and third surgical procedures, to achieve cytoreduction. Percutaneous radiofrequency ablation has proved effective in local control of hepatic tumors. We report early experience with percutaneous radiofrequency ablation in the management of isolated foci of metastatic ovarian cancer and assess the efficacy of the technique in achieving and maintaining local control by percutaneous cytoreduction. CONCLUSION: Percutaneous radiofrequency ablation is effective in achieving local control in selected patients with metastasis from ovarian cancer. In patients with limited macroscopic disease, cytoreduction can be achieved without surgery.

Adult↗
PubMed2005

Percutaneous radiofrequency ablation of renal cell carcinoma.

Conventional curative therapy for renal cell carcinoma has been open nephrectomy. However, several less invasive and/or nephron-sparing procedures have been developed as alternatives in selected patients. The newest of these therapeutic modalities involves percutaneous image-guided ablation with straight or expandable needle applicators that deposit energy. Radiofrequency ablation is the modality for which there is the largest reported experience with percutaneous application, and involves the use of electrical current to generate frictional heating of tissue. Animal studies confirm the ability of radiofrequency ablation to cause regions of necrosis within normal kidney and in VX2 tumors. Clinically, radiofrequency ablation of small renal cell carcinoma is increasingly being performed in selected patients who are not ideal surgical candidates. Results are excellent for small exophytic tumors, but successful treatment is less likely as tumor size increases or the location becomes more central. Complete treatment of most tumors requires one or more overlapping ablations with the needle electrodes positioned so as to cause necrosis in the entire volume of tumor. The number of overlapping ablations and the position of the needle electrodes vary based on tumor size and geometry. For very large tumors, pre-ablation catheter embolization may enhance the results of ablation by decreasing blood flow and perfusion mediated cooling. Following ablation, imaging with CT or MR is performed to assess the result and to diagnose any residual tumor so that it can be treated. Because the tumor remains in situ, imaging follow-up continues indefinitely. The complication rate of radiofrequency ablation is favorable when compared to surgical techniques. Long-term survival data are not yet available.

Animals↗
PubMed2005

Image-guided percutaneous radiofrequency ablation and incidence of post-radiofrequency ablation syndrome: prospective survey.

PURPOSE: To evaluate prospectively the incidence of post-radiofrequency (RF) ablation syndrome and determine its impact on the quality of life in the 10 days after percutaneous RF ablation. MATERIALS AND METHODS: This study was approved by the institutional review board and was HIPAA compliant. Informed consent was obtained for this survey in all patients by the interventional nurse coordinators. Thirty-six patients (20 men, 16 women; mean age, 69.3 years; range, 40-88 years) underwent RF ablation for 26 liver tumors and 17 renal tumors. Twenty control patients (11 men, nine women; mean age, 60.8 years; range, 35-76 years) underwent biopsy of focal liver lesions or renal lesions. With a standardized questionnaire, a telephone survey was conducted on days 1, 3, 5, and 10 after RF ablation or biopsy. The symptoms and interference with lifestyle were documented prospectively with a numeric intensity scale by using grades 0-10. Statistical analysis with Fisher exact test and analysis of variance was performed. RESULTS: After RF ablation, 15 (42%) patients developed low-grade fever (P < .001), 29 (81%) had flulike symptoms (P < .001), and four were asymptomatic. Symptoms peaked on day 3 and mainly resolved by day 10. Twelve (33%) patients had complete post-RF ablation syndrome: fever and flulike symptoms (P = .005). Flulike symptoms were more prolonged when they were accompanied with fever, peaked on day 5, and resolved more quickly for patients with renal lesions than they did for patients with liver lesions. Four patients had persistent fever caused by pneumonia (n = 2), pleural effusion and atelectasis (n = 1), or liver abscess (n = 1). No control patients developed both fever and flulike symptoms. Post-RF ablation patients with symptoms experienced significantly greater pain and interference with general and work activities, which peaked on day 1, than did control patients (P = .01 [pain], P < .001 [general and work activities]). CONCLUSION: Complete post-RF ablation syndrome occurs in approximately one-third of patients but is self-limiting within 10 days after the procedure. Persistent or late-onset fever may indicate concurrent infection elsewhere or possible abscess formation. SUPPLEMENTAL MATERIAL: radiology.rsnajnls.org/cgi/content/full/237/3/1097/DC1

Adult↗
PubMed2005

Radiofrequency ablation of renal cell carcinoma: part 1, Indications, results, and role in patient management over a 6-year period and ablation of 100 tumors.

OBJECTIVE: The objectives of our article are to review our experience with radiofrequency ablation of renal cell carcinoma and to assess size and location as predictors of the ability to achieve complete necrosis by imaging criteria. MATERIALS AND METHODS: Over a 6-year period, 100 renal tumors in 85 patients underwent radiofrequency ablation at a single institution. The absence of enhancement on CT or MRI after radiofrequency ablation was interpreted as complete coagulation necrosis. Results were analyzed by tumor size and location using multivariate analysis. A p value of 0.05 or less was considered significant. RESULTS: All 52 small (3 cm) and all 68 exophytic tumors underwent complete necrosis regardless of size, although many large tumors (> 3 cm) required a second ablation session. Using multivariate analysis, we found that both small size (p < 0.0001) and noncentral location (p = 0.0049) proved to be independent predictors of complete necrosis after a single ablation session. Location was a significant predictor (p = 0.015) of complete necrosis after any number of sessions, whereas size showed a strong trend (p = 0.059) toward predicting success after any number of sessions. Complications were either self-limited or readily treated and included hemorrhage (major, n = 2; minor, n = 3), inflammatory track mass (n = 1), transient lumbar plexus pain (n = 2), ureteral injury (n = 2), and skin burns (n = 1). CONCLUSION: Radiofrequency ablation is a promising minimally invasive therapy for renal cell carcinoma in patients who are not good operative candidates. Small size and noncentral location are favorable tumor characteristics, although large tumors can sometimes be successfully treated with multiple ablation sessions.

Aged↗
PubMed2005

Radiofrequency ablation of renal cell carcinoma: part 2, Lessons learned with ablation of 100 tumors.

OBJECTIVE: The objective of our study was to review radiofrequency ablation of 100 renal tumors and lessons learned with respect to electrode approach, effects on collecting system, bowel proximity, and patterns of residual disease. MATERIALS AND METHODS: Over 6 years, 100 renal tumors in 85 patients underwent radiofrequency ablation. Images were reviewed to determine the following: effect of initial electrode approach at and parallel to the tumor-kidney interface; effect of collecting system proximity to the tumor and to the zone of ablation; bowel proximity to the tumor and strategies to protect bowel; patterns of residual disease; and approaches at subsequent sessions. RESULTS: The initial placement of the electrode at and parallel to the tumor-kidney interface did not result in significantly fewer overlapping ablations (p = 0.91) or a lower rate of residual disease (p = 0.86). Direct contiguity of tumor or zone of ablation to the collecting system did not increase the complication rate. However, obscuration of calyces by a central tumor was a significant predictor of collecting system hemorrhage necessitating treatment (p < 0.001) seen in three of nine tumors obscuring calyces. Clinically significant urine leaks were rare (1/100) and related to downstream obstruction. There were no bowel complications despite the fact that 27 of the tumors were within 1 cm of bowel. Protective strategies progressed from reliance on electrode positioning to hydrodissection. Residual patterns were predominantly nodules or crescents, and straight electrodes were commonly used to approach residual disease. CONCLUSION: Initial electrode position at and parallel to the tumor-kidney interface does not result in less difficult or more successful ablations. Contiguity of tumor or zone of ablation to the collecting system does not increase the risk of complications, but obscuration of calyces does. Bowel complications are rare, and protection with hydrodissection is becoming more common. Residual tumor presents as nodules or crescents of persistent enhancement.

Aged↗
PubMed2005

Percutaneous ablation of kidney tumors in nonsurgical candidates.

Although resection currently remains the standard of care for renal carcinoma, the search for less invasive treatments has led to alternative surgical approaches. Even less invasive, and appropriate for many groups of patients, is percutaneous radiofrequency ablation, which induces tumor necrosis via lethal hyperthermia. Multiple series of renal tumors treated with percutaneous ablation in vivo and left in situ have been published; these series reveal that for small renal tumors, radiofrequency ablation results in complete necrosis at imaging in 79% to 100% of cases. Because current results come from tumors left in situ with short postablation follow-up, long-term results are necessary to compare outcomes to surgical standards. Complication rates are lower than those following partial nephrectomy. Future reports will shed light on the long-term outcomes of percutaneous ablation and the relative advantages and disadvantages of various technologies for thermal ablation.

Carcinoma, Renal Cell↗
PubMed2004

Recurrent abdominal and pelvic abscesses: incidence, results of repeated percutaneous drainage, and underlying causes in 956 drainages.

OBJECTIVE: We undertook this study to determine the incidence and results of repeated (secondary) percutaneous abscess drainage performed on recurrent abscesses after successful initial (primary) percutaneous abscess drainage. MATERIALS AND METHODS: Imaging studies from patients who underwent multiple drainages were reviewed to define a cohort of patients who underwent secondary percutaneous abscess drainage after successful initial percutaneous abscess drainage of the same abscess. Medical records of these patients were then reviewed to assess the results of secondary percutaneous abscess drainage. RESULTS: Forty-five abscesses in 43 patients required secondary percutaneous abscess drainage. Twenty-four of the 43 patients avoided surgery. Secondary percutaneous abscess drainage was successful in evacuating the abscess cavity in 39 (91%) of 43 patients. Duration of drainage and time until recurrence were not significant predictors for avoiding surgery. Mean duration of secondary percutaneous abscess drainage was significantly longer than mean duration of primary percutaneous abscess drainage, but duration of secondary percutaneous abscess drainage (25 vs 14 days, respectively; p = 0.007) did not differ significantly between patients who ultimately required surgery and those who did not (17 vs 11 days, respectively; p = 0.10). Time to recurrence ranged from 2 days to 1 year (mean, 51 days). CONCLUSION: After successful primary percutaneous abscess drainage, secondary percutaneous abscess drainage of recurrent abscesses succeeded in evacuating the abscess cavity in most patients, and surgery was avoided by slightly more than half. Patients with postoperative abscesses were significantly more likely to avoid surgery (p = 0.008), whereas patients with pancreatic abscesses were significantly more likely to require it (p = 0.03).

Abdominal Abscess↗
PubMed2003

Renal cell carcinoma: clinical experience and technical success with radio-frequency ablation of 42 tumors.

PURPOSE: To evaluate clinical experience with percutaneous image-guided radio-frequency (RF) ablation of renal cell carcinoma (RCC) and to assess factors that may influence technical success. MATERIALS AND METHODS: Thirty-four patients who underwent RF ablation of 42 RCC tumors during a 3.5-year period were evaluated. Overlapping ablations were performed on the basis of tumor size and geometry. Technical success was defined as elimination of areas that enhanced at imaging within the entire tumor. With the exception of those patients with renal insufficiency, who were followed up with unenhanced and gadolinium-enhanced magnetic resonance imaging, patients were followed up with unenhanced and contrast material-enhanced computed tomography. Univariate analysis of the results was performed with the Fisher exact test to assess the effect of tumor size and location on technical success. P 3.0 cm) tumors, presence of a tumor component in the renal sinus was a significant negative predictor of technical success (P =.004); only five of these 11 tumors were completely treated, compared with 11 of 11 tumors without a renal sinus component. A similar analysis was not possible for small tumors because no small tumors involved the renal sinus. Four complications occurred in a total of 54 ablation sessions: one minor hemorrhage, two major hemorrhages, and one ureteral stricture. CONCLUSION: RF ablation of RCC can be successful in exophytic RCC tumors up to 5.0 cm in size. Tumors larger than 3.0 cm with a component in the renal sinus are more difficult to treat but can be ablated successfully.

Adult↗
PubMed2002

Percutaneous radiofrequency ablation of nodal metastases.

We report our experience with percutaneous image-guided radiofrequency (RF) ablation to treat isolated nodal metastases. Four patients underwent image-guided percutaneous RF ablation of metastatic disease involving retrocrural nodes, retroperitoneal nodes, or pelvic nodes. Coagulation necrosis was achieved in all cases.

Aged↗
PubMedDate not supplied

The difficult biopsy: let's make it easier.

Image-guided percutaneous biopsies of abdominal and pelvic organs are an integral part of the daily practice of many radiologists. Fortunately, most image-guided percutaneous biopsies are straightforward. At times, however, image-guided percutaneous biopsies can be technically challenging due to various factors, including proximity of surrounding vessels or organs, "moving targets" due to respiratory motion, or difficulties in detecting lesions with certain imaging modalities. The purpose of this manuscript is to discuss techniques that can be utilized to increase the successful biopsy of "difficult" lesions. Choices of imaging modality for guiding needle placement will be discussed, as will the use of alternative access routes such as transgluteal, transvaginal, and other transorgan approaches. Factors to improve the accessibility of lesions, including patient positioning and the timing of contrast injections that improve lesion detection, will be discussed.

Biopsy↗
PubMedDate not supplied

State of the art in adrenal imaging.

The purposes of this article were to outline the current state of adrenal imaging, to highlight new developments, and to review the current radiologic advances that provide improved functional and structural information about adrenal disorders.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Urine leaks and urinomas: diagnosis and imaging-guided intervention.

Urine leaks from the kidney, ureter, bladder, and urethra most commonly result from trauma. Urinomas may be occult initially and may lead to complications such as abscess formation and electrolyte imbalances if not promptly diagnosed and appropriately managed. Radiologists play a key role in diagnosing urine leaks and determining their cause and extent. Contrast material-enhanced computed tomography (CT) with delayed imaging, CT cystography, and retrograde urethrography are the diagnostic imaging studies of choice. Studies such as intravenous pyelography, antegrade and retrograde pyelography, renal scintigraphy, and imaging-guided needle aspiration may play complementary diagnostic roles. In some instances, the role of the radiologist ends with the diagnosis of urine leaks, after which patients are treated conservatively or perhaps surgically. Uncomplicated renal urine leaks, extraperitoneal urinary bladder rupture, and type 1 urethral injuries are generally managed conservatively. Urine leaks that require more extensive, imaging-guided treatment can usually be managed safely and effectively with a combination of percutaneous urinoma drainage catheters, percutaneous nephrostomy catheters, ureteral stents, and bladder drainage. In the appropriate setting, use of these management options may reduce urinoma-related complications and limit or totally eliminate the need for urologic surgery.

Adolescent↗