Ultrasound-guided thoracic facet injections: description of a technique.

OBJECTIVES: The purpose of this study was to describe a technique using ultrasound guidance to perform thoracic facet joint injections. METHODS: A single examiner used ultrasound to localize paired thoracic facet joints from T1-2 through T10-11 on a fresh frozen cadaveric specimen. This was done using a 2- to 5-MHz curvilinear transducer over the target facet in the sagittal plain with the cadaver in the prone position. Target facets were identified using the most inferior rib as a starting point and scanning medially toward its axial attachment and further medially and slightly superior over the most caudal thoracic facet (T11-12). Subsequent ipsilateral facet joints were identified by simply moving the transducer superiorly in the sagittal plain until the next cephalad facet was encountered. After identification, injections were performed using a long-axis or "in-line" approach with continual visualization of the needle into each facet joint. After needle placement, computed images were obtained from a fluoroscopy machine capable of 3-dimensional reconstruction to assess the location of the needle tips. After this, 0.5 mL of an iodinated contrast agent was injected, and another 3-dimensional reconstruction was performed to assess the location of the injected agent. A senior radiology resident reviewed the computed images in coronal, axial, and sagittal planes. Accuracy was determined in terms of contrast location, graded as either intra-articular or extra-articular. RESULTS: Sixteen (80%) of 20 injections performed showed intra-articular contrast spread. CONCLUSIONS: We describe a relatively feasible technique for performing thoracic facet joint injections using ultrasound guidance. Further verification of this technique, and modification if applicable, should be performed before directly applying this technique in a clinical practice setting.

MRI after technically successful renal cryoablation: early contrast enhancement as a common finding.

OBJECTIVE: The purpose of this study was to assess the MRI appearance and enhancement of renal masses within 36 hours after cryoablation. MATERIALS AND METHODS: From March 2003 through January 2008, 129 patients underwent imaging-guided cryoablation for renal masses. Twenty-three of these patients underwent MRI within 36 hours after ablation. During MRI, acquisition of axial T1- and T2-weighted images was followed by administration of a gadolinium contrast agent. Standard follow-up included MRI 3-6 months after ablation. RESULTS: Eight of the 23 renal masses imaged within 6-36 hours after ablation were enhanced on MR images. Five of the eight lesions exhibited homogeneous enhancement, and the other three had heterogeneous or rim enhancement. Seven of the eight lesions exhibited no enhancement at the 6-month follow-up examination. One patient underwent follow-up imaging 10 months rather than 3-6 months after the procedure, but no enhancement was seen. T2-weighted signal intensity was mixed among the 23 renal masses. T1-weighted signal intensity was mixed among the 23 renal masses and the eight lesions that became enhanced, but there was a trend for higher T1 signal intensity at the 3- to 6-month follow-up examination. CONCLUSION: The high proportion of enhancing lesions 3 months after treatment and the resolution of enhancement 6 months afterward suggest that it may be reasonable to wait 6 months after technically successful renal cryoablation before performing contrast-enhanced MRI.

Clinical benefits and economic analysis of pegylated liposomal doxorubicin/vincristine/dexamethasone versus doxorubicin/vincristine/dexamethasone in patients with newly diagnosed multiple myeloma.

Pegylated liposomal doxorubicin has reduced toxicity compared with conventional doxorubicin. In a noninferiority trial randomizing patients to receive pegylated liposomal doxorubicin 40 mg/m(2) and vincristine 1.4 mg/m(2) (maximum, 2 mg) intravenously on day 1 plus reduced-dose dexamethasone 40 mg orally on days 1-4 (DVd; n = 97) or conventional doxorubicin 9 mg/m(2) per day and vincristine 0.4 mg per day continuous intravenous infusion on days 1-4 plus reduced-dose dexamethasone (VAd; n = 95) for >/= 4 cycles. Treatment was repeated every 4 weeks until maximal response, disease progression, unacceptable toxicity, or until patients underwent transplantation. Treatment cost was estimated by applying standard US costs in 2004 to recorded health-care resource utilization units. Outcome measures included response, toxicity, and treatment cost. Objective response rates (DVd, 44%; VAd, 41%), progression-free survival (hazard ratio, 1.11; P = 0.69), and overall survival (hazard ratio, 0.88; P = 0.67) were similar between treatment groups. DVd was associated with significantly less grade 3/4 neutropenia or neutropenic fever (10% vs. 24%; P = 0.01), less sepsis, antibiotic use, growth factor support, and alopecia, but more hand-foot syndrome. Study drug costs were significantly higher for DVd versus VAd; however, lower costs for drug administration and supportive care more than offset this difference, resulting in nominally lower overall study drug treatment costs for DVd (DVd, $34,442; VAd, $35,846; P = 0.76). The DVd regimen demonstrated similar efficacy and cost with less toxicity and supportive care compared with VAd. This should improve clinical utility and optimize the opportunity for transplantation.

Distortion-product otoacoustic emission suppression growth in normal and noise-exposed rabbits.

This study investigated noise-induced changes in suppression growth (SG) of distortion product otoacoustic emissions (DPOAEs). Detailed measurements of SG were obtained in rabbits as a function of f2 frequencies at four primary-tone levels. SG measures were produced by using suppressor tones (STs) presented at two fixed distances from f2. The magnitude of suppression was calculated for each ST level and depicted as contour plots showing the amount of suppression as a function of the f2 frequency. At each f2, SG indices included slope, suppression threshold, and an estimate of the tip-to-tail value. All suppression measures were obtained before and after producing a cochlear dysfunction using a monaural exposure to a 2-h, 110-dB SPL octave-band noise centered at 2 kHz. The noise exposure produced varying amounts of cochlear damage as revealed by changes in DP-grams and auditory brainstem responses. However, average measures of SG slopes, suppression thresholds, and tip-to-tail values failed to mirror the mean DP-gram loss patterns. When suppression-based parameters were correlated with the amount of DPOAE loss, small but significant correlations were observed for some measures. Overall, the findings suggest that measures derived from DPOAE SG are limited in their ability to detect noise-induced cochlear damage.