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S Nahum Goldberg

Publications and source records attributed to S Nahum Goldberg.

At least 19 recordsLinked to original sources
PubMed2006

Improved tumor destruction with arsenic trioxide and radiofrequency ablation in three animal models.

PURPOSE: To assess the extent of tumor blood flow reduction that is achievable with arsenic trioxide (As2O3) and the effect of As2O3 on radiofrequency (RF)-induced coagulation. MATERIALS AND METHODS: All animal protocols and experiments were approved by an institutional animal care and use committee before the start of the study. Experiments were conducted in three tumor models: intrarenal VX2 sarcoma in 27 rabbits, RCC 786-0 human renal cell carcinoma in 24 nude mice, and R3230 mammary adenocarcinoma in 40 rats. One dose (0-7.5 mg per kilogram of body weight) of As2O3 was administered (intraperitoneally in rodents, intravenously in rabbits) 1, 6, or 24 hours before standardized RF ablation, which was performed by using a 1-cm active tip, with mean temperatures of 70 degrees C +/- 2 (standard deviation) for 5 minutes in rodents and 90 degrees C +/- 2 for 6 minutes in rabbits. Laser Doppler flowmetry was used to quantify changes in blood flow, which were compared with diameters of induced tumor coagulation. Comparisons between groups were performed by using Student t tests or analysis of variance. The strengths of correlations between As2O3, tumor blood flow, and RF-induced coagulation were assessed by using linear and higher-order regression models and reported as R2 computations. RESULTS: Administration of As2O3 significantly (P < .05) reduced blood flow and increased tumor destruction in all tumor models. In VX2 sarcoma tumors, 1 mg/kg As2O3 reduced mean tumor blood flow to 46% +/- 13 of the normal value. The mean resultant coagulation (1.1 cm +/- 0.1) was significantly greater than that achieved with RF ablation alone (0.6 cm +/- 0.1, P < .01). In RCC 786-0 and R3230 tumors, 5 mg/kg As2O3 reduced mean tumor blood flow to 57% +/- 6 and 46% +/- 6 of normal, respectively, increasing mean ablation extent to 0.8 cm +/- 0.1 for both models, compared with those achieved with the control treatment (0.6 cm +/- 0.1 and 0.5 cm +/- 0.1, respectively; P < .05 for both comparisons). Dose studies revealed correlations between drug dose, tumor blood flow, and RF-induced coagulation in all three tumor models (R2 = 0.60-0.79). Maximal RF synergy was observed 1 hour after As2O3 administration. CONCLUSION: As2O3 administration represents a transient noninvasive method of reducing tumor blood flow during RF ablation, enabling larger zones of tumor destruction in multiple tumor models.

Adenocarcinoma↗
PubMed2006

Multiple-image in-room CT imaging guidance for interventional procedures.

This HIPAA-compliant study was approved by the institutional review board; informed consent was not required. The purpose of this study was to retrospectively compare room use time for interventional procedures performed with multiple-image multi-detector row computed tomographic (CT) fluoroscopy (n=196) and single-image spiral CT fluoroscopy (n=175). There was no statistically significant difference in age, sex, or procedural type between the two groups. The median room use time was 90 minutes (interquartile range, 65-120 minutes) for the single-image technique and 75 minutes (interquartile range, 60-105 minutes) for the multiple-image technique. A two-sample t test with equal variance assumption on the log-transformed data showed a statistically significant difference in log time (P<.001) between the two groups. This time savings could potentially have a substantial clinical effect on resource use and patient throughput.

Adult↗
PubMed2006

Colonic perforation at CT colonography: assessment of risk in a multicenter large cohort.

PURPOSE: To assess retrospectively the incidence, clinical features, and treatment of colonic perforation at computed tomographic (CT) colonography in a large multicenter cohort. MATERIALS AND METHODS: The study was performed in accordance with the institutional ethics committees' requirements of a retrospective review in each of the participating centers, and no informed consent was required. A review of all patients who underwent CT colonography between January 2001 and December 2004 in 11 medical centers representing more than 95% of studies performed in a single country was performed to determine the rate of colorectal perforation. Data about patient demographics and patient- and procedure-related risk were recorded. Information about the location of the perforation, its likely mechanism, and treatment was collected. Analysis included calculation of rates of colonic perforation and surgical treatment and of 95% confidence intervals. RESULTS: A total of 11 870 CT colonographic studies were performed in 6837 (57.6%) men and 5033 (42.4%) women (mean age, 59.9 years; range, 38-90 years) with seven cases of colorectal perforation, yielding a risk rate of 0.059% (one of 1696 studies; 95% confidence interval: one of 974, 971 of 6537). The mean age of the patients with perforation was 77.8 years. Six (84%) of seven cases of perforation occurred in symptomatic patients at high risk for colorectal neoplasia, and one (16%) occurred in an asymptomatic average-risk patient. All studies were performed after insufflation of room air. Six (84%) cases of perforation occurred in patients in whom a rectal tube was inserted, and in five of them, a balloon was inflated. Five (71%) cases of perforation occurred in the sigmoid colon; and two (29%), in the rectum. Four (57%) patients (one in 2968 patients; 95% confidence interval: 1.5 in 10 000, 14.7 in 10 000) required surgical treatment. Possible factors that contributed to perforation were left inguinal hernia containing colon (n = 4), severe diverticulosis (n = 3), and obstructive carcinoma (n = 1). CONCLUSION: Perforation of the colon and rectum is a rare complication of CT colonography. Older age and underlying concomitant colonic disease were present in patients with perforation.

Adult↗
PubMed2006

Microwave ablation: results with a 2.45-GHz applicator in ex vivo bovine and in vivo porcine liver.

PURPOSE: To characterize the relationship between applied power and treatment duration in their effect on extent of coagulation produced with a 2.45-GHz microwave applicator in both an ex vivo and a perfused in vivo liver model. MATERIALS AND METHODS: All experimentation was approved by the Institute of Animal Care and Use Committee. Multiple tissue ablations were performed in ex vivo bovine liver (120 ablations) and in vivo porcine liver (45 ablations) with a 5.7-mm-diameter 2.45-GHz microwave applicator. The applied power was varied from 50 to 150 W (in 25-W increments ex vivo and 50-W increments in vivo), while treatment duration varied from 2 to 20 minutes (in eight time increments for ex vivo and five for in vivo liver). Three-dimensional contour maps of the resultant short- and long-axis coagulation diameters were constructed to identify the optimal parameters to achieve maximum coagulation in both ex vivo and in vivo models. Multivariate analysis was performed to characterize the relationship between applied power and treatment duration. RESULTS: Power and treatment duration were both associated with coagulation diameter in a sigmoidal fashion (ex vivo, R(2) = 0.78; in vivo, R(2) = 0.74). For ex vivo liver, the maximum short-axis coagulation diameter (7.6 cm +/- 0.2 [standard deviation] by 12.3 cm +/- 0.8) was achieved at greatest power (150 W) and duration (20 minutes). In vivo studies revealed a sigmoidal relationship between duration and coagulation size, with a relative plateau in coagulation size achieved within 8 minutes duration at all power levels. After 8 minutes of treatment at 150 W, the mean short-axis coagulation diameter for in vivo liver was 5.7 cm +/- 0.2 by 6.5 cm +/- 1.7, which was significantly larger than the corresponding result for ex vivo liver (P < .05). CONCLUSION: Large zones of ablation can be achieved with the 2.45-GHz microwave applicator used by the authors. For higher-power ablations, larger zones of coagulation were achieved for in vivo liver than for ex vivo liver with short energy applications, a finding previously not seen with other ablation devices, to the authors' knowledge.

Animals↗
PubMed2006

Characterization of the RF ablation-induced 'oven effect': the importance of background tissue thermal conductivity on tissue heating.

PURPOSE: To determine the effect of background tissue thermal conductivity on RF ablation heating using ex vivo agar phantoms and computer modelling. METHOD: Two-compartment cylindrical agar phantom models (5% agar, 5% NaCl, 3% sucrose) were constructed. These included a standardized inner compartment (2 cm diameter, 4 cm length, 0.25% agar) representing a tumour, surrounded by an outer compartment representing background tissue. The thermal conductivity of the outer compartment was varied from 0.48 W m-1 degrees Celsius (normal liver) to 0.23 W m-1 degrees Celsius (fat) by adding a fat-saturated oil-based solute (10-90%) to the agar. RF ablation was applied at 2000 mA current for 2 min. Temperatures were recorded up to 4 cm from the electrode tip at 1 cm intervals. Subsequently, a 2-D finite element computer model was used to simulate RF ablation of 2-24 min duration for tumours measuring 2-4 cm in diameter surrounded by tissues of different thermal conductivity with the presence or absence of perfusion (0-5 kg m-3 s-1) (n = 44). A comparison of results was performed. RESULTS: In agar phantoms, the amount of fat in the background tissue correlated with thermal conductivity as a negative exponential function (r2 = 0.98). Significantly increased temperatures were observed at the edge of the inner compartment (1 cm from the electrode tip) as the fat content of the outer compartment increased (p < 0.01). Thus, temperatures at 2 min measured 31.5 +/- 2.2 degrees Celsius vs 45.1 +/- 3.1 degrees Celsius for thermal conductivities of 0.46 W m-1 degrees Celsius (10% fat) and 0.23 W m-1 degrees Celsius (90% fat), respectively. On the other hand, higher levels of fat led to lower temperature increases in the background compartment (0.2 +/- 0.3 degrees Celsius for 90% fat vs. 1.1 +/- 0.05 degrees Celsius for 10% fat, p < 0.05). Phantom thermal heating patterns correlated extremely well with computer modelling (r2 = 0.93), demonstrating that background tissues with low thermal conductivity increase heating within the central tumour, particularly for longer durations of RF ablation and in smaller tumours. Furthermore, computer modelling demonstrated that increases in temperature at the tumour margin for background tissues of lower thermal conductivity persisted in the presence of perfusion, with a clinically relevant 4.5 degrees Celsius difference between background thermal conductivities of fat and soft tissue for a 3 cm tumour with perfusion of 2 kg m-3 s-1, treated for 12 min. CONCLUSION: Lower thermal conductivity of background tissues significantly increases temperatures within a defined ablation target. These findings provide insight into the 'oven effect' (i.e. increased heating efficacy for tumours surrounded by cirrhotic liver or fat) and highlight the importance of both the tumour and the surrounding tissue characteristics when contemplating RF ablation efficacy.

Agar↗
PubMed2006

Chemical tumor ablation with use of a novel multiple-tine infusion system in a canine sarcoma model.

PURPOSE: To determine whether larger confluent zones of ablation can be achieved in chemical ablation with use of a multiple-tine infusion device compared with standard needle infusion in a solid tumor model. MATERIALS AND METHODS: Multiple canine venereal sarcomas (N=42) were implanted in nine mildly immunosuppressed dogs (treated with 10 mg/kg cyclosporin A twice daily). Tumors incubated for 8-12 weeks grew to a diameter of 5.4 cm+/-1.0. With ultrasound guidance, 8-56 mL of 100% ethanol or 15% acetic acid (diluted in saturated saline solution) were injected in aliquots (2-8 mL) at multiple distances (radius of 0-2 cm) from the needle axis with use of a multiple-tine infusion device. Presence of fluid reflux at the needle puncture site and resultant coagulation diameters were measured within 1 hour and compared with the results of infusion with a standard 18-gauge needle. RESULTS: Multiple-tine infusion enabled greater fluid infusion (15 mL+/-3 to 53 mL+/-3 depending on protocol) than standard needle injection (8 mL+/-1) before reflux was observed at the puncture site (P<.01). Additionally, progressive gains in contiguous tumor coagulation were achieved because acetic acid was infused as far as 2 cm from the needle axis with the multiple-tine device (P<.01; R(2)=0.59; y=0.5x+2.9). Optimal coagulation was achieved with the infusion of 4-mL aliquots at 0.5 cm and 1.0 cm from the needle, followed by three 4-mL or 8-mL aliquots (40 degrees rotation between infusions) at 1.5 cm and 2.0 cm from the needle (32 mL+/-0 and 53 mL+/-3 total, respectively). This yielded confluent short-axis coagulation diameters of 4.9 cm+/-1.0 and 5.4 cm+/-1.0, respectively, which were significantly greater than the measurement of 3.1 cm+/-0.4 achieved with standard needle infusion (P<.01). Smaller and noncontiguous foci of coagulation foci (1.7 cm+- 0.5) were seen with the use of ethanol for standard needle and multiple-tine infusions. CONCLUSIONS: Chemical ablation with 15% acetic acid with use of a multiple-tine infusion device resulted in larger diameters of contiguous tumor coagulation and enabled greater volumes of infusion than standard needle infusion or ethanol ablation. This suggests that chemical ablation with acetic acid infused with use of a multiple-tine device may overcome some of the difficulties seen with the use of conventional needle chemical ablation injection alone, such as irregular ablation and fluid reflux up the needle tract.

Acetic Acid↗
PubMed2006

Impact of CT-guided drainage in the treatment of diverticular abscesses: size matters.

OBJECTIVE: Our objective was to determine whether abscess size can be used as a discriminating factor to guide management of patients with diverticular abscesses. MATERIALS AND METHODS: We performed a word search of our CT database between July 2001 and July 2002 for the CT diagnosis of diverticulitis. CTs were retrospectively reviewed as consensus opinion of two reviewers. CTs were evaluated for presence of an abscess, its location, maximum diameter, and feasibility of percutaneous abscess drainage. Abscesses were categorized into smaller than 3 cm and larger than or equal to 3 cm, and the management of these groups was compared. RESULTS: Thirty-one abscesses were noted in 30 (17%) of 181 patients with a CT diagnosis of diverticulitis. Twenty-two (73%) of 30 patients had 23 abscesses, all of which were smaller than 3 cm and were treated and resolved with antibiotics alone (p < 0.001). Eight (36%) of 22 required surgical treatment. Eight (26%) of 31 abscesses had a maximum diameter larger than or equal to 3 cm. Four (50%) of eight patients with abscesses 3.4-4.1 cm were treated with antibiotics alone. Four (50%) of eight abscesses, all larger than 4.1 cm, were treated with CT-guided drainage and one abscess required repeat drainage. After resolution of symptoms, surgery was performed in five (62.5%) of eight of the larger abscesses. CONCLUSION: Patients with abscesses smaller than 3 cm in size can be treated with antibiotics alone and, in some cases, as outpatients, and may not uniformly require surgery. This is also likely true for patients with abscesses 3-4 cm in size, although our results in this group were limited by a small sample size. Patients with abscesses larger than or equal to 4 cm can be managed with CT-guided abscess drainage followed by referral for surgical treatment.

Abdominal Abscess↗
PubMed2005

Image-guided tumor ablation: standardization of terminology and reporting criteria.

The field of interventional oncology with use of image-guided tumor ablation requires standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison between treatments that use different technologies, such as chemical (ethanol or acetic acid) ablation, and thermal therapies, such as radiofrequency, laser, microwave, ultrasound, and cryoablation. This document provides a framework that will hopefully facilitate the clearest communication between investigators and will provide the greatest flexibility in comparison between the many new, exciting, and emerging technologies. An appropriate vehicle for reporting the various aspects of image-guided ablation therapy, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings, are outlined. Methods for standardizing the reporting of follow-up findings and complications and other important aspects that require attention when reporting clinical results are addressed. It is the group's intention that adherence to the recommendations will facilitate achievement of the group's main objective: improved precision and communication in this field that lead to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes.

Catheter Ablation↗
PubMed2005

Reduced tumor growth with combined radiofrequency ablation and radiation therapy in a rat breast tumor model.

PURPOSE: To determine whether use of combined radiofrequency (RF) ablation and external-beam radiation therapy increases end-point survival beyond that with either RF ablation or radiation therapy alone in an animal tumor model. MATERIALS AND METHODS: With a protocol approved by the institutional animal care and use committee, R3230 mammary adenocarcinoma (12.5 mm +/- 0.6 [standard deviation]) was implanted subcutaneously into 107 female Fischer 344 rats. Initially, 42 tumors were randomized into four treatment groups: (a) RF ablation (70 degrees C for 5 minutes) alone, (b) RF ablation followed by radiation therapy with a total dose of 20 Gy, (c) 20-Gy radiation alone, and (d) no treatment. Another 19 tumors were randomized to receive (e) RF ablation (70 degrees C for 5 minutes) followed by 5-Gy radiation, (f) 5-Gy radiation alone, or (g) no treatment. Animals were followed up until survival end point (either until tumor growth to 30 mm in diameter, or for 120 days if no tumor was seen in mammary fat pad or chest wall). Results were analyzed with the Kaplan-Meier method. Histopathologic analysis was performed in 15 additional tumors at survival end point and 18 other representative tumors at other specified end points. RESULTS: Combined RF ablation and 20-Gy radiation resulted in complete local control in nine (82%) of 11 tumors, compared with one (9%) of 11 tumors treated with RF ablation alone and one (17%) of six treated with RF ablation and 5-Gy radiation (P < .001). No local control was achieved in rats with radiation therapy alone or in controls. Median end-point survival was 12 days for controls, 20 days with RF ablation or 5-Gy radiation alone, 30 days with RF ablation plus 5-Gy radiation, 40 days with 20-Gy radiation alone, and 120 days with RF ablation plus 20-Gy radiation. Mean end-point survival was 13 days +/- 5 (standard deviation) for the control group, 34 days +/- 31 with RF ablation alone, and 43 days +/- 16 with 20-Gy radiation alone. Mean survival was significantly greater with 20-Gy radiation and RF ablation combined: 94 days +/- 34 (P < .001 compared with all other groups). Mean survival for rats that received 5-Gy radiation with RF ablation versus without was 46 days +/- 37 versus 24 days +/- 11, respectively. CONCLUSION: Combined RF ablation and external-beam radiation therapy increased animal survival compared with that with either of the treatments alone or with no treatment.

Animals↗
PubMed2005

Image-guided tumor ablation: standardization of terminology and reporting criteria.

The field of interventional oncology with use of image-guided tumor ablation requires standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison between treatments that use different technologies, such as chemical (ethanol or acetic acid) ablation, and thermal therapies, such as radiofrequency (RF), laser, microwave, ultrasound, and cryoablation. This document provides a framework that will hopefully facilitate the clearest communication between investigators and will provide the greatest flexibility in comparison between the many new, exciting, and emerging technologies. An appropriate vehicle for reporting the various aspects of image-guided ablation therapy, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings, are outlined. Methods for standardizing the reporting of follow-up findings and complications and other important aspects that require attention when reporting clinical results are addressed. It is the group's intention that adherence to the recommendations will facilitate achievement of the group's main objective: improved precision and communication in this field that lead to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes. The intent of this standardization of terminology is to provide an appropriate vehicle for reporting the various aspects of image-guided ablation therapy.

Catheter Ablation↗
PubMed2005

Combined radiofrequency ablation and adjuvant liposomal chemotherapy: effect of chemotherapeutic agent, nanoparticle size, and circulation time.

PURPOSE: To evaluate the effects of liposomal chemotherapeutic agent, nanoparticle size, and liposome circulation time on tissue coagulation and intratumoral drug uptake when radiofrequency (RF) ablation is combined with adjuvant intravenous liposomal chemotherapy in an animal breast tumor model. MATERIALS AND METHODS: Ninety-one R3230 mammary adenocarcinoma nodules were implanted in 48 Fischer rats. First, standardized RF ablation was combined with intravenous liposomal doxorubicin, cisplatin, or 5-fluorouracil (35 tumors each). Second, three different-sized doxorubicin-containing nanoparticle preparations were combined with standardized RF ablation. Last, two doxorubicin-containing liposome preparations with different blood elimination half-lives were combined with RF ablation. Coagulation diameter and interstitial doxorubicin concentration were measured 48 hours after treatment and compared with use of statistical analysis. RESULTS: All combinations of RF with liposomal chemotherapy caused significantly greater tumor necrosis than RF alone (P<.05). Significantly increased necrosis was observed with intravenous liposomal RF/doxorubicin and RF/cisplatin compared with intravenous liposomal RF/5-fluorouracil (P<.01). Greater coagulation was observed with RF combined with 100-nm nanoparticles compared with 20-nm or 250-nm nanoparticles (P=.01 and P=.04, respectively). Additionally, greater intratumoral doxorubicin uptake was observed in the group treated with 20-nm nanoparticles compared with those treated with other sizes of nanoparticles (P<.05). RF plus liposomal doxorubicin produced greater coagulation and intratumoral doxorubicin uptake than RF plus 1,2-dipalmitoyl-sn-glycero-3-phosphatidic acid (P<.05). CONCLUSION: When combined with RF ablation, modification of adjuvant intravenous liposomal chemotherapy, including nanoparticle size, circulation time, and chemotherapeutic agent, can influence intratumoral drug accumulation and tissue coagulation.

Adenocarcinoma↗