Laser Interstitial Therapy Research Articles

Systematic review of ablation techniques for the treatment of malignant or aggressive benign lesions in children.

Ablation techniques are widely used for solid malignant tumors in adults. There is no large series assessing the effectiveness of local ablative therapies in the treatment of malignant or aggressive benign lesions in children. To review the existing evidence on the techniques and results of ablation for pediatric solid malignant or aggressive benign tumors. We searched MEDLINE for papers published between 1995 and 2012 that reported outcomes of radiofrequency, microwave and cryoablation, interstitial laser therapy, irreversible electroporation and percutaneous ethanol injection for patients younger than 18years old. Data collection included factors related to the patient, tumor biology, ablation technique and cancer-specific endpoints. Additional series of predominantly adults including data on patients younger than 18years old were also identified. We identified 28 patients treated by ablation in 29 regions: 5 patients undergoing ablation for liver lesions, 9 patients for lung metastases, 11 patients for bone and/or soft tissue and 4 patients for kidney or pancreas. The ablation was performed to treat primary tumors, local recurrences and metastases. The histology of the tumors was osteosarcoma in 6 patients, Wilms tumor in 3, rhabdomyosarcoma in 3, hepatoblastoma in 3, desmoid tumor in 3, adrenocortical carcinoma in 2 and a single case each of leiomyosarcoma, Ewing sarcoma, paraganglioma, solid-pseudopapillary neoplasm, sacrococcygeal teratoma, hepatic adenoma, juxtaglomerular cell tumor and plantar fibromatosis. Eighteen of the patients (64%) experienced a complication, but only 6 (21%) of these needed treatment other than supportive care. Although ablative techniques are feasible and promising treatments for certain pediatric tumors, large multicenter prospective trials will be needed to establish efficacy.

Imaging and intervention in prostate cancer: Current perspectives and future trends.

Prostate cancer is the commonest malignancy in men that causes significant morbidity and mortality worldwide. Screening by digital rectal examination (DRE) and serum prostate-specific antigen (PSA) is used despite its limitations. Gray-scale transrectal ultrasound (TRUS), used to guide multiple random prostatic biopsies, misses up to 20% cancers and frequently underestimates the grade of malignancy. Increasing the number of biopsy cores marginally increases the yield. Evolving techniques of real-time ultrasound elastography (RTE) and contrast-enhanced ultrasound (CEUS) are being investigated to better detect and improve the yield by allowing “targeted” biopsies. Last decade has witnessed rapid developments in magnetic resonance imaging (MRI) for improved management of prostate cancer. In addition to the anatomical information, it is capable of providing functional information through diffusion-weighted imaging (DWI), magnetic resonance spectroscopy (MRS), and dynamic contrast-enhanced (DCE) MRI. Multi-parametric MRI has the potential to exclude a significant cancer in majority of cases. Inclusion of MRI before prostatic biopsy can reduce the invasiveness of the procedure by limiting the number of cores needed to make a diagnosis and support watchful waiting in others. It is made possible by targeted biopsies as opposed to random. With the availability of minimally invasive therapeutic modalities like high-intensity focused ultrasound (HIFU) and interstitial laser therapy, detecting early cancer is even more relevant today. [18F]--fluorodeoxyglucose positron emission tomography/computed tomography (18FDG PET/CT) has no role in the initial evaluation of prostate cancer. Choline PET has been recently found to be more useful. Fluoride-PET has a higher sensitivity and resolution than a conventional radionuclide bone scan in detecting skeletal metastases.

Earlyvslate intervention in twin reversed arterial perfusion sequence

To compare two different management approaches in prenatally diagnosed twin reversed arterial perfusion (TRAP) sequence. Retrospective analysis of all cases with TRAP sequence diagnosed in one center over a period of 10 years. Prior to 2010, all cases were managed expectantly until 19 weeks' gestation; thereafter, patients could choose either radiofrequency ablation (RFA) or expectant management (Group A). From 2010 onward all patients were offered interstitial laser at the time of diagnosis (12 weeks at the earliest) or expectant management (Group B). Forty cases were included in the study. In Group A, 23 cases were diagnosed at a mean gestational age of 19.9 ± 6.3 weeks. Sixteen patients were managed expectantly (13 survivors, 81%), while six underwent RFA at the time of diagnosis and one later in pregnancy (six survivors, 86%). In Group B, 17 cases were diagnosed at a mean gestational age of 16.4 ± 4.7 weeks. Six patients chose expectant management (five survivors, 83%) and 11 had interstitial laser therapy at the time of diagnosis (eight survivors, 73%). The loss rate of the pump twin was not significantly different between Group A and Group B (three of 23 vs four of 17; P = 0.3). In Group B the rates of preterm premature rupture of membranes (PPROM) and delivery < 34 weeks were significantly lower, and gestational age at birth as well as birth weight were significantly higher than in Group A. Despite the limitations resulting from its retrospective design, our study on management of TRAP sequence adds some evidence in favor of prophylactic intervention by intrafetal laser from 12 weeks onward.

99 Interstitial and intraarticular laser therapy – a new option for difficult pain syndromes

99 Interstitial and intraarticular laser therapy – a new option for difficult pain syndromes

Outcome of Twin Reversed Arterial Perfusion Sequence following Treatment with Interstitial Laser: A Retrospective Study

Objectives: To determine the outcome of twin reversed arterial perfusion (TRAP) sequence treated with or scheduled for treatment with interstitial laser therapy. Methods: This is a retrospective study on ten pregnancies diagnosed with TRAP sequence. Seven of the ten pregnancies were treated with interstitial laser therapy, and two pregnancies were scheduled for later treatment. One pregnancy was treated with fetoscopic laser ablation and excluded from analysis. The delivery reports of all pregnancies were collected, the neonatal health status recorded and the median time of delivery and the treatment to delivery interval calculated. Results: Six of seven pump fetuses in TRAP pregnancies treated with interstitial laser therapy at a median of 16+2 (range 13+1 to 20+3) gestational weeks were born healthy at a median of 38+0 (range 34+3 to 40+6) gestational weeks. One fetus treated with interstitial laser died after the procedure at 20+3 weeks. Two pump twins scheduled for later treatment died before the gestational age of 16 weeks. The median treatment to delivery interval for the surviving fetuses was 153 days (range 128-194). Conclusion: Treatment of TRAP sequence by interstitial laser therapy is feasible from the 13th week of gestation and has a good outcome.

Perinatal outcomes of antenatally investigated sacrococcygeal teratomas (SCTS) at a single tertiary fetal medicine centre

AimsSacrococcygeal teratomas (SCTs) are one of the commonest neonatal tumours but occur infrequently with an incidence of 1:40 000. We reviewed the perinatal outcomes of all antenatally detected cases of...

Effects of pulsed electromagnetic fields on benign prostate hyperplasia

Benign prostate hyperplasia (BPH) has been treated with various types of electromagnetic radiation methods such as transurethral needle ablation (TUNA), interstitial laser therapy (ILC), holmium laser resection (HoLRP). In the present study, the effects of a noninvasive method based on the exposure of patients with BPH to a pulsative EM Field at radiofrequencies have been investigated. Twenty patients with BPH, aging 68-78 years old (y.o), were enrolled in the study. Patients were randomly divided into two groups: the treatment group (10 patients, 74.0 ± 5.7 y.o) treated with the α-blocker Alfusosin, 10 mg/24 h for at least 4 weeks, and the electromagnetic group (10 patients, 73.7 ± 6.3 y.o) exposed for 2 weeks in a very short wave duration, pulsed electromagnetic field at radiofrequencies generated by an ion magnetic inductor, for 30 min daily, 5 consecutive days per week. Patients of both groups were evaluated before and after drug and EMF treatment by values of total PSA and prostatic PSA fraction, acid phosphate, U/S estimation of prostate volume and urine residue, urodynamic estimation of urine flow rate, and International Prostate Symptom Score (IPSS). There was a statistically significant decrease before and after treatment of IPSS (P < 0.02), U/S prostate volume (P < 0.05), and urine residue (P < 0.05), as well as of mean urine flow rate (P < 0.05) in patients of the electromagnetic group, in contrast to the treatment group who had only improved IPSS (P < 0.05). There was also a significant improvement in clinical symptoms in patients of the electromagnetic group. Follow-up of the patients of this group for one year revealed that results obtained by EMFs treatment are still remaining. Pulsed electromagnetic field at radiofrequencies may benefit patients with benign prostate hyperplasia treated by a non-invasive method.

Giant placental chorioangioma: natural history and pregnancy outcome

Giant placental chorioangiomas are associated with a high prevalence of pregnancy complications and a poor perinatal outcome. The aim of the study was to evaluate the natural history, intrauterine treatment and outcome of pregnancies complicated by giant placental chorioangioma. This was a retrospective study of 19 cases of giant placental chorioangioma, in which the natural history, intrauterine treatment and outcome of pregnancy were evaluated. Eighteen of the 19 cases were associated with a wide variety of fetal complications, including polyhydramnios, growth restriction, hyperdynamic circulation, cardiomegaly, anemia and non-immune hydrops. Two-thirds of the cases developed complications that required either elective delivery for fetal growth restriction (n = 6) or intervention for cardiovascular effects (n = 7). Fetal therapy, when required, was tailored to the particular complication and resulted in a successful pregnancy in all cases. The presence of large placental chorioangioma is associated with the development of fetal growth restriction and hyperdynamic state in a significant number of cases. This series elucidates some of the putative underlying mechanisms for these complications, and reports on a safe and effective treatment modality, percutaneous ultrasound-guided interstitial laser therapy.

Interstitial Laser Therapy of Breast Fibroadenomas With 6 and 8 Year Follow-Up

Fibroadenomas are non-cancerous breast tumors commonly seen in teenagers but also found in women at the time of first mammogram. They have distinct physical findings and imaging features but the definitive diagnosis is made by ultrasound or stereotactic guided needle biopsy. Treatment options are observation or surgical removal. Recently, removal by ultrasound-guided technique has been reported. Alternatively, the tumor may be ablated within the breast by cold (cryotherapy) or by heat (laser, radiofrequency, focused ultrasound and microwave). In this paper the laser treatment in two patients, one with bilateral fibroadenomas, with 6 and 8 year follow-up is presented.

Interstitial laser therapy in hemangiomatosis of the liver – A case report

Abstract Objective Diffuse neonatal hemangiomatosis (DNH) is a severe disease with multiple organ involvement. If left untreated, it results in high mortality rates. Death occurs due to intractable heart failure following arteriovenous shunting or due to massive cerebral or gastrointestinal bleeding. If there are large liver hemangiomas and medical treatment is not sufficient, it is necessary to use interventional or surgical procedures such as embolization or ligation of the hepatic artery. We present another local tumor destruction procedure to treat liver hemangiomas in DNH, the interstitial laser therapy (ILT). Method ILT was performed in a 3-month-old male infant suffering from DNH with intractable heart failure and multiple liver hemangiomas. Due to the severity of the infant's condition and the minimally invasive character of the treatment, the ILT was performed directly in the neonatal intensive care unit. The ILT was carried out percutaneously by guiding a bare fiber (0.6 mm core diameter) via a puncture needle into the pathologically altered liver region. A Nd:YAG laser (1064 nm) was used as a light source for ILT because its light penetrates deeply into biological tissue. Tissue destruction was achieved with moderate laser power of 4–6 W and a long application time of 90–300 s. Using these applied physical laser parameters, almost spherical volumes of coagulation necrosis could be obtained with diameters of up to 1–2 cm. Puncture and the laser application were monitored by color-coded duplex sonography (CCDS). A decrease in color signal intensity at the tip of the bare fiber indicated the increasing tissue coagulation during application time. Results After 2 sessions of ILT of liver manifestation in 10 days the cardiac output was reduced by 50%. Postoperative Doppler imaging showed fibrosis in the treated areas of the liver. The child was transferred back to his country of origin but he died 3 months later of intracranial bleeding. Conclusion In our opinion interstitial laser therapy can be an effective minimally invasive method to treat life-threatening liver hemangiomas in diffuse neonatal hemangiomatosis.

Reporting Standards for Percutaneous Thermal Ablation of Renal Cell Carcinoma

WITH the increasing incidence of renal cell carcinoma (RCC) in the United States and the increasing proportion of patients with tumors detected at an early stage (1–5), nephron-sparing approaches are becoming more popular. These alternatives to radical nephrectomy include partial nephrectomy, wedge resection, and, more recently, in situ thermal ablation. Five-year survival rates after partial nephrectomy are equivalent to those after radical nephrectomy (6–8), supporting the rationale of in situ tumor destruction to further reduce morbidity and invasiveness. In situ thermal destruction of RCC uses techniques that destroy tumor tissue through heating (eg, radiofrequency [RF] ablation, microwave ablation, laser interstitial therapy, high-intensity focused ultrasound [US]) or freezing (eg, cryotherapy). Each of these techniques relies on controlled energy delivery to minimize collateral damage to normal renal parenchyma and other surrounding structures. In the United States, RF ablation and cryoablation are currently the most widely used techniques for in situ RCC destruction. Thermal ablation of RCC may be performed percutaneously, laparoscopically, or through open surgery. Our current understanding of the role of percutaneous thermal ablation in the management of primary RCC is limited by a paucity of prospective studies (9,10). Given the relative newness of this technology, most series to date report short-term or midterm outcomes, with no reports extending to 5 years of survival outcomes. No randomized trials have been performed to date comparing thermal ablation against a gold standard (ie, partial nephrectomy) or against other thermal ablation techniques. The optimal size range of RCC amenable to thermal ablation has not been clearly defined and is closely related to anatomic factors that influence the ability to deposit sufficient thermal dose to coagulate tissue, including proximity to major vessels and the urinary collecting system, which can act as a heat sink. The kidney has approximately four times the blood flow of the liver, so convective heat loss during thermal ablation is potentially significant (11). The role of percutaneous thermal ablation compared with laparoscopic or open thermal ablation also remains a topic of controversy. The combination of thermal ablation with other imageguided therapies (eg, transcatheter embolization) and adjuvant therapies such as chemotherapy and antiangiogenic agents for larger RCCs in patients who are poor operative candidates is another potential use of this technique. Although most recent reports of percutaneous RCC ablation have involved RF ablation, other ablation technologies are now available with percutaneous applicators (eg, cryoablation, microwave, laser interstitial therapy), and reporting standards should be uniform for all forms of energy-based ablation. This document provides recommended reporting standards for physicians performing percutaneous thermal ablation of primary RCC and will serve as a template in the design of clinical trials to further evaluate this technology. From the Section of Vascular and Interventional Radiology, Department of Radiology (T.W.I.C.), New York University School of Medicine, New York, New York; Department of Radiology (S.F.M.), University of Western Ontario, Peterborough Regional Health Center, Peterborough, Ontario, Canada; Department of Radiology, Gastrointestinal/Genitourinary Division (D.A.G.), Massachusetts General Hospital; Department of Radiology (S.N.G.), Beth Israel Deaconess Medical Center, Boston; Department of Radiology (C.J.G.), Lahey Clinic Medical Center, Burlington; Department of Radiology (D.A.P.), University of Massachusetts Memorial Health Care, Worcester, Massachusetts; Department of Radiology (T.B.K.), University of California San Diego Medical Center, San Diego, California; Department of Radiology (D.S.), The Reading Hospital and Medical Center, Reading, Pennsylvania; and Department of Radiology (J.F.C.), University of Colorado Health Sciences Center, Denver, Colorado. Received June 19, 2006; revision requested June 19; final revision received June 29; and accepted July 3. Address correspondence to T.W.I.C., c/o Tricia McClenny, Society of Interventional Radiology, 3975 Fair Ridge Dr, Suite 400 North, Fairfax, VA 22033; E-mail: mcclenny@sirweb.org

4.09] Interstitial laser therapy of hemangiomatosis of the liver

Objective Diffuse neonatal hemangiomatosis (DNH) is a severe disease with multiple organ involvement. Untreated, there is a high mortality of approximately 60%. Death occurs due to intractable heart failure following arterio-venous shunting or due to massive cerebral or gastrointestinal bleeding. If there are large liver hemangiomas and medical treatment is not sufficient, interventional or surgical procedures like embolization or ligation of the hepatic artery has been used. We present another local tumor destruction procedure to treat liver hemangiomas in DNH, the interstitial laser therapy (ILT). Patient and methods We performed ILT in an infant with intractable heart failure in large liver hemangiomas in DNH. Due to the severe condition of the infant and the minimally invasive character of the treatment we performed the ILT directly in the neonatal intensive care unit. The ILT was carried out by guiding the laser applicator via a puncture needle into the pathologically altered liver region. Due to photon absorption and heat conduction coagulative and hyperthermic effects were obtained leading to an immediate or delayed tissue destruction. As light source for ILT a Nd:YAG laser (1064 nm) was used because its light penetrates deeply into biological tissue. Tissue destruction was achieved with moderate laser power of 5 W and a long application time of 90–300 s. With these applied physical laser parameters nearly spherical volumes of coagulation necrosis could be obtained showing diameters of up to 1–2 cm. The puncture and the laser application were monitored by color-coded duplex sonography (CCDS). The decrease in intensity of color signal at the tip of the bare fiber indicates the increasing tissue coagulation during application time. Results After 2 sessions of ILT of liver manifestation in ten days the cardiac output was reduced by 50%. Postoperative Doppler imaging showed fibrosis in the treated areas of the liver. The child was transferred back to his country. The boy died 2 month later because of progressive cranial and pulmonary manifestation. Conclusion In our opinion interstitial laser therapy can be an effective minimally invasive method to treat life threatening liver hemangiomas in diffuse neonatal hemangiomatosis.

CT-Guided Brachytherapy (CTGB) versus Interstitial Laser Ablation (ILT) of Colorectal Liver Metastases

To compare local tumor control after percutaneous tumor ablation by interstitial laser therapy (ILT) or CT-guided brachytherapy (CTGB). In a matched pair analysis including 18 patients with 36 liver metastases of colorectal primary, both ILT and CTGB were performed in different lesions. The following matching factors were considered: (i) tumor size ≤ 5 cm, and (ii) execution of chemotherapy after tumor ablation. Primary endpoint was local tumor control. Treated lesions were identical in terms of tumor size and all matching criteria were fulfilled in all patients except for the performance of adjuvant chemotherapy. Median follow-up was 14 months (3–24 months) for both groups. Only five of 18 patients (28%) demonstrated local tumor progression after CTGB, whereas in ten of 18 patients (56%) tumor progression was found after ILT. Differences encountered were significant for all patients (p = 0.04), whereas in those who fulfilled all matching criteria (n = 14) the level of statistical significance was not reached (p = 0.23). CTGB demonstrated superior local tumor control compared to ILT in long-term follow-up.

Interstitial laser therapy for fetal reduction in monochorionic multiple pregnancy: loss rate and association with aplasia cutis congenita

To evaluate experience with interstitial laser therapy for intrafetal vascular ablation in monochorionic (MC) multiple pregnancy. MC pregnancies that underwent fetal reduction between 1998 and 2007 by interstitial laser therapy were reviewed. Indications were twin reversed arterial perfusion sequence (TRAP) (n = 10), twin-to-twin transfusion (6), discordant abnormality (7) or growth (1) and high-order multiples (6). Thirty pregnancies treated at 15 weeks (median, range: 11 weeks-20 weeks, 5 days) had no technical failures but four manifested procedure-related amniorrhexis. Four of 38 remaining fetuses suffered intrauterine death (IUFD) within 24 h, giving an early procedure-related fetal loss rate of 10% per pregnancy and 11% per fetus. A further five IUFDs occurred within 2 weeks, giving a maximum procedure-related loss rate of 27% per pregnancy and 24% per fetus. Median gestation at delivery was 37 weeks (18 weeks, 1 day-41 weeks, 3 days) for pregnancies continuing > 2 weeks. Perinatal survival was 26 of 38 (68%) in nonreduced fetuses. Two of 26 neonates (8%) were diagnosed with aplasia cutis congenita (ACC). Interstitial laser therapy in complicated MC pregnancies carries significant risks of unintended fetal loss and may be associated with ACC.

Aplasia cutis in association with a triplet pregnancy and fetus papyraceus

A baby boy weighing 1605 g was born at 35 weeks’ gestation with an unexpected large abdominal wall skin defect. This had been an in vitro fertilisation pregnancy in which...

MRI‐guided interventions of the breast

MRI has proven to be a very reliable diagnostic tool in the detection and differential diagnosis of breast lesions. Some lesions are, even in retrospect, not detectable in x-ray or ultrasound images but MRI is able to detect lesions at a much smaller size than the average size of lesions depicted by x-ray and ultrasound. The aim in the future is to develop combined procedures where imaging, biopsy, and interventional therapies are combined in a single outpatient procedure. As a step toward this goal different interventional procedures are useful that include interstitial laser therapy (ILT), radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFU), microwave ablation therapy, and cryotherapy. In this overview the main features and initial results of these procedures are described and discussed.

MR-Thermometrie bei 1,5 Tesla zur thermischen Ablation mittels laserinduzierter Thermotherapie

Evaluation of thermometry with fast MR sequences for laser-induced interstitial laser therapy (LITT) and verification of the thermometric results with a fiber-optic thermometer. In vitro experiments were conducted using an agarose gel mixture and pig liver lobes. MR-guided LITT was performed using a laser power between 3 and 15 watts. Thermometry was performed using longitudinal relaxation time T1 and proton resonance frequency shift (PRF) methods under acquisition of amplitude and phase shift images. PRF was measured with a fast spoiled GRE sequence. Four different sequences were used for T1 thermometry: gradient echo (GE), TrueFISP (TRUFI), Saturation Recovery Turbo-FLASH (SRTF) and Inversion Recovery Turbo-FLASH (IRTF) sequences. The temperature was controlled using a fiber-optic Luxtron device and correlated with the MR temperature. The range of applied and monitored temperatures exceeded 80 degrees Celsius. The temperature dependence showed a good linear relationship up to 60 degrees Celsius. Calibration experiments for the T1 method delivered coefficients of determination from 0.977 to 0.997 for agarose and from 0.958 to 0.995 for the pig liver samples. The IRTF sequence had the highest temperature sensitivity (agarose 0.99, liver 1.19). During LITT the TRUE-FISP sequence exhibited a strong nonlinear relationship. R (2) of this sequence was 0.809 in the agarose experiments. The average temperature errors when heated up to 80 degrees Celsius were 3.86-11.38 degrees Celsius for Agarose gel and 5.7-12.16 degrees Celsius for the liver tissue. SRTF and IRTF sequences exhibited the most linear relationship with temperature but were more dependent on tissue differences. The accuracy of the temperature measurement is sufficient for controlling the coagulation area of the LITT. PRF is the method of choice since it shows the best linear correlation with fiber-optic temperature. If only T1 sequences are concerned, the FLASH sequence is preferred. It is the most robust, though not the most accurate, T1 sequence.

Reporting Standards for Percutaneous Thermal Ablation of Renal Cell Carcinoma

WITH the increasing incidence of renal cell carcinoma (RCC) in the United States and the increasing proportion of patients with tumors detected at an early stage (1–5), nephron-sparing approaches are becoming more popular. These alternatives to radical nephrectomy include partial nephrectomy, wedge resection, and, more recently, in situ thermal ablation. Five-year survival rates after partial nephrectomy are equivalent to those after radical nephrectomy (6–8), supporting the rationale of in situ tumor destruction to further reduce morbidity and invasiveness. In situ thermal destruction of RCC uses techniques that destroy tumor tissue through heating (eg, radiofrequency [RF] ablation, microwave ablation, laser interstitial therapy, high-intensity focused ultrasound [US]) or freezing (eg, cryotherapy). Each of these techniques relies on controlled energy delivery to minimize collateral damage to normal renal parenchyma and other surrounding structures. In the United States, RF ablation and cryoablation are currently the most widely used techniques for in situ RCC destruction. Thermal ablation of RCC may be performed percutaneously, laparoscopically, or through open surgery. Our current understanding of the role of percutaneous thermal ablation in the management of primary RCC is limited by a paucity of prospective studies (9,10). Given the relative newness of this technology, most series to date report short-term or midterm outcomes, with no reports extending to 5 years of survival outcomes. No randomized trials have been performed to date comparing thermal ablation against a gold standard (ie, partial nephrectomy) or against other thermal ablation techniques. The optimal size range of RCC amenable to thermal ablation has not been clearly defined and is closely related to anatomic factors that influence the ability to deposit sufficient thermal dose to coagulate tissue, including proximity to major vessels and the urinary collecting system, which can act as a heat sink. The kidney has approximately four times the blood flow of the liver, so convective heat loss during thermal ablation is potentially significant (11). The role of percutaneous thermal ablation compared with laparoscopic or open thermal ablation also remains a topic of controversy. The combination of thermal ablation with other imageguided therapies (eg, transcatheter embolization) and adjuvant therapies such as chemotherapy and antiangiogenic agents for larger RCCs in patients who are poor operative candidates is another potential use of this technique. Although most recent reports of percutaneous RCC ablation have involved RF ablation, other ablation technologies are now available with percutaneous applicators (eg, cryoablation, microwave, laser interstitial therapy), and reporting standards should be uniform for all forms of energy-based ablation. This document provides recommended reporting standards for physicians performing percutaneous thermal ablation of primary RCC and will serve as a template in the design of clinical trials to further evaluate this technology. From the Section of Vascular and Interventional Radiology, Department of Radiology (T.W.I.C.), New York University School of Medicine, New York, New York; Department of Radiology (S.F.M.), University of Western Ontario, Peterborough Regional Health Center, Peterborough, Ontario, Canada; Department of Radiology, Gastrointestinal/Genitourinary Division (D.A.G.), Massachusetts General Hospital; Department of Radiology (S.N.G.), Beth Israel Deaconess Medical Center, Boston; Department of Radiology (C.J.G.), Lahey Clinic Medical Center, Burlington; Department of Radiology (D.A.P.), University of Massachusetts Memorial Health Care, Worcester, Massachusetts; Department of Radiology (T.B.K.), University of California San Diego Medical Center, San Diego, California; Department of Radiology (D.S.), The Reading Hospital and Medical Center, Reading, Pennsylvania; and Department of Radiology (J.F.C.), University of Colorado Health Sciences Center, Denver, Colorado. Received June 19, 2006; revision requested June 19; final revision received June 29; and accepted July 3. Address correspondence to T.W.I.C., c/o Tricia McClenny, Society of Interventional Radiology, 3975 Fair Ridge Dr, Suite 400 North, Fairfax, VA 22033; E-mail: mcclenny@sirweb.org

Energy ablative techniques for treatment of small renal tumors

The success of partial nephrectomy for the treatment of small renal cancers has led to the development of energy ablative technologies, which are less invasive alternatives for performing nephron-sparing surgery. Currently, cryoablation and radiofrequency ablation are the two most reported technologies. Both technologies use very different means to cause cellular injury. Additionally, three newer technologies, high-frequency ultrasound ablation, laser interstitial therapy, and microwave therapy are emerging in the literature. Three- and 4-year data for cryoablation and radiofrequency ablation are now becoming available. On the basis of these studies, it is clear that ablative technologies can be effective treatments for select small renal tumors. It is also evident that both percutaneous and laparoscopic approaches offer minimal morbidity. As long-term (5 years and greater) outcome data for ablative technologies accumulate, we are likely to see an increase in clinical reports, including more patients who may be candidates for extirpative surgery. Technology will advance, leading to smaller probes with larger treatment zones, making it possible to treat larger tumors and potentially even tumors in the advanced disease state.

Beneficial effect of combined aspiration and interstitial laser therapy in patients with benign cystic thyroid nodules: a pilot study

The aim of this study was to evaluate the effect of combined cyst aspiration and ultrasound-guided interstitial laser photocoagulation (ILP) on recurrence rate and the volume of benign cystic thyroid nodules. 10 euthyroid outpatients with a solitary and cytologically benign partially cystic thyroid nodule causing local discomfort were assigned to cyst aspiration followed by ultrasound-guided ILP and followed for 12 months. The ILP was performed under continuous ultrasound-guidance and with an output power of 2.5-3.5 W. The volume of the nodules was assessed by means of ultrasound and determination of the amount of aspirated cyst fluid, thereby calculating the volume of the solid part. Follow-up included ultrasound and determination of thyroid function. Pressure and cosmetic complaints were evaluated on a visual analogue scale. The median initial volume of the cystic nodule decreased from 9.6 ml [6.8;15.5 (quartiles)] to 3.5 ml [2.7;9.0 (quartiles)] (p = 0.0001), and the median cyst volume from 3.0 ml [2.0;6.0 (quartiles)] to 0 ml [0;0.5 (quartiles)] (p = 0.0001) during follow-up. Recurrence of the cystic part was defined as a cyst volume > 1 ml. In eight of 10 patients there was no recurrence of the cystic part. Both pressure symptoms and cosmetic complaints were significantly reduced. The only side effect was mild pain or tenderness for a few days. Our study suggests that complete cyst aspiration and subsequent ultrasound-guided ILP of benign cystic thyroid nodules is a feasible and safe technique, resulting in a significant reduction in the volume of both the solid and the cystic component. A large-scale prospective randomized study is warranted.