MR imaging-guided radio-frequency thermal ablation in the pancreas in a porcine model with a modified clinical C-arm system.

PURPOSE: To test the hypotheses that (a) magnetic resonance (MR) imaging-guided radio-frequency (RF) thermal ablation in the pancreas is safe and feasible in a porcine model and (b) induced thermal lesion size can be predicted with MR imaging monitoring. MATERIALS AND METHODS: MR imaging-guided RF ablation was performed in the pancreas of six pigs. A 17-gauge monopolar RF probe was inserted into the pancreas with MR imaging guidance, and RF was applied for 10 minutes. After postprocedural imaging (T2-weighted, short inversion time inversion-recovery [STIR], and T1-weighted imaging before and after intravenous administration of gadodiamide), the pigs were observed for 7 days and follow-up MR images were acquired. The pigs were sacrificed, and pathologic examination was performed. RESULTS: Successful RF probe placement was accomplished in all pigs; the interventional procedure took 46-80 minutes. Thermal lesions were 12-15 mm perpendicular to the probe track and were best seen on STIR and contrast material-enhanced T1-weighted images with a radiologic and/or pathologic mean difference in RF lesion diameter of 1.7 mm +/- 1.0 (SD) and 0.8 mm +/- 1.2, respectively. Diarrhea was the only side effect during the 1-week follow-up; no clinical signs of pancreatitis occurred. CONCLUSION: MR imaging-guided RF thermal ablation in the pancreas is feasible and safe. Induced thermal lesion size can best be monitored with STIR and contrast-enhanced T1-weighted images. In the future, RF ablation may offer an alternative treatment option for pancreatic cancer.     

Clinical aspects of ballistic peripheral nerve injury: shrapnel versus gunshot

Objectives

Ballistic injuries to peripheral nerves pose special challenges in terms of indications, timing and type of surgical intervention. The aim of the present work was to analyze our experience in the surgical treatment of peripheral nerve ballistic injuries with respect to the mechanism of injury (gunshot versus shrapnel), and identify common and dissimilar prognostic factors in both types of injury.

Methods

This study was conducted on 42 patients totaling 58 nerves. Twenty-two patients (32 nerves) were injured by gunshot and 20 patients (26 nerves) by shrapnel. Median postoperative follow-up was 33 months (range 12 months to 14 years).

Results

Overall postoperative outcome appears to be more favorable for gunshot-wound (GSW) patients than shrapnel-injured patients, especially in terms of neuropathic pain relief (75 % vs. 58 % respectively, p < 0.05). Presence of foreign particles in shrapnel injured patients has a negative impact on the surgical outcome in terms of rate of pain improvement (28 % compared to 67 % in patients with and without foreign particles, respectively). Nerve graft reconstruction, rather than neurolysis, seems to be the more beneficial treatment for shrapnel-induced neuropathic pain (100 % vs. 47 % in improvement rate, respectively). Early surgical intervention (median 2 months after injury) significantly relieved neuropathic pain in 83 % of shrapnel-injured patients compared to 58 % in patients operated later.

Conclusions

This study suggests that shrapnel injury is more destructive for nerve tissue than gunshot injury. Our impression is that early surgical intervention in shrapnel injuries and split nerve grafting (especially when small fragments are recognized in the nerve) significantly improve the patient’s functional activity and quality of life.     

Risk stratification in patients with remote prior myocardial infarction using rest-stress myocardial perfusion spect: prognostic value and impact on referral to early catheterization

BACKGROUND: Little is known about the prognostic value of myocardial perfusion single photon emission computed tomography (SPECT) in patients with remote prior myocardial infarction (MI). METHODS AND RESULTS: We identified 1413 consecutive patients with remote prior MI who underwent rest-stress myocardial perfusion SPECT. Semiquantitative visual analysis of 20 SPECT segments was used to define the summed stress, rest, and difference scores. The number of non-reversible segments was used as an index of infarct size. During follow-up (>or=1 year), 118 hard events occurred: 64 cardiac deaths (CDs) and 54 recurrent MIs. Annual CD and hard event rates increased significantly as a function of SPECT abnormality. For summed stress scores less than 4, 4 to 8, 9 to 13, and more than 13, the annual CD rates were 0.4%, 0.9%, 1.7%, and 3.5%, respectively (P =.002). Patients with small MI (<4 non-reversible segments) and no or mild ischemia (summed difference score or=4 non-reversible segments) had moderate to high annual CD rates (3.7%-6.6%) regardless of the extent of ischemia. Nuclear testing added incremental prognostic information to pre-scan information. Compared with a strategy in which all patients are referred to catheterization, a strategy that referred only those patients with a risk for CD of greater than 1% by myocardial perfusion SPECT resulted in a 41.6% cost savings. CONCLUSIONS: Myocardial perfusion SPECT adds incremental value to pre-scan information and is highly predictive and cost-efficient in the risk stratification of patients with remote prior MI. Patients with normal or mildly abnormal scan results or small MI in combination with absent or mild ischemia have a low risk for CD.     

Clinical comparison of full-field digital mammography and screen-film mammography for detection of breast cancer

OBJECTIVE: The purpose of this work is to compare full-field digital mammography and screen-film mammography for the detection of breast cancer in a screening population. SUBJECTS AND METHODS: Full-field digital mammography was performed in addition to screen-film mammography in 6736 examinations of women 40 years old and older presenting for screening mammography at either of two institutions. Two views of each breast were acquired with each technique. The digital and screen-film mammograms were each interpreted independently. In addition to a clinical assessment, each finding was assigned a probability of malignancy for use in receiver operating characteristic analysis. In cases in which the digital and screen-film interpretations differed, a side-by-side analysis was performed to determine the reasons for the discrepancy. With few exceptions, findings detected on either technique were evaluated with additional imaging and, if warranted, biopsy. RESULTS: Additional evaluation was recommended on at least one technique in 1467 cases. These additional evaluations led to 181 biopsies and the detection of 42 cancers. Nine cancers were detected only on digital mammography, 15 were detected only on screen-film mammography, and 18 were detected on both. The difference in cancer detection is not statistically significant (p > 0.1). Digital mammography resulted in fewer recalls than did screenfilm mammography (799 vs 1007, p < 0.001). The difference between the receiver operating characteristic curve area for digital (0.74) and screen-film (0.80) mammography was not significant (p > 0.1). Reasons for discrepant interpretations of cancer were approximately equally distributed among those relating to lesion conspicuity, lesion appearance, and interpretation. CONCLUSION: No significant difference in cancer detection was observed between digital mammography and screen-film mammography. Digital mammography resulted in fewer recalls than did screen-film mammography.     

Obsessive–Compulsive Personality Traits in Youth with Obsessive–Compulsive Disorder

While interest in the relationship between obsessive–compulsive disorder (OCD) and obsessive compulsive personality disorder has increased, there are currently no studies that have examined the presence of obsessive compulsive personality traits (OCPTs) in youth. The current study sought to determine the latent factors and psychometric properties of a modified version of the Childhood Retrospective Perfectionism Questionnaire (CHIRP) and examine the correlates of specific OCPTs (e.g., rigidity, perfectionism) in youth with OCD. Participants included 96 treatment-seeking youth diagnosed with primary OCD (and a parent). Parents and youth completed measures of OCPTs, OCD severity, depression, and disability. A confirmatory factor analysis of the modified CHIRP resulted in a two-factor model: perfectionism and preoccupation with details. The CHIRP and its subscales demonstrated acceptable internal consistency and preliminary evidence for convergent and divergent validity. Obsessive compulsive traits in youth were also found to be associated with the checking, symmetry and contamination symptom dimensions.     

Relative neuroprotective effects hyperbaric oxygen treatment and TLR4 knockout in a mouse model of temporary middle cerebral artery occlusion

Purpose: To examine the effects of hyperbaric oxygen (HBO) therapy and knockout of toll-like receptor 4 (TLR4) on the outcome of temporary middle cerebral artery occlusion (MCAO) in a mouse model. Materials and Methods: MCAO was induced in anesthetized male C57Bl/6 mice (WT) and TLR4 knockout mice (TLR4^?/?) using an intra-arterial filament method. After 30 or 90 min, the filament was removed, and the mice were given either no treatment (WT and TLR4^?/- groups) or HBO (WT only). Mice were euthanized 24 h after MCAO, and the brain infarct area was examined using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Results: In the WT group, without treatment, lesion volume was 120 ± 13 mm³ in the mice subjected to 30 min’ MCAO and 173 ± 23 mm³ in the mice subjected to 90 min’ MCAO. Respective values with HBO treatment were 66.5 ± 36.7 mm³ and 53.2 ± 17.2 mm³. The difference was significant only for 90-minute MCAO (p < 0.01, nonparametric test). In the TLR4^?/? group (all untreated), lesion volume was 95.9 ± 17.9 after 90 min of MCAO, which was significantly lower than in the untreated WT animals (p < 0.05, nonparametric test). Conclusions: A single treatment of HBO immediately after MCAO followed by 24 h’ reperfusion significantly reduces edema and may improve perfusion. TLR4 knockout protects mice from MCAO damage, but to a lesser extent than HBO treatment.     

Surgical Myocardial Revascularization versus Percutaneous Coronary Intervention with Drug-Eluting Stents in Octogenarian Patients

Objective: Our goal was to compare the clinical outcomes of octogenarian (or older) patients who are referred for either surgical or percutaneous coronary revascularization.Methods: We retrospectively evaluated the outcomes of all patients 80 years of age who had undergone coronary artery bypass grafting (CABG) with an internal mammary artery or had undergone a percutaneous coronary intervention (PCI) with a sirolimus-eluting stent to the left anterior descending artery in our center between May 2002 and December 2006.Results: Of the 301 patients, 120 underwent a PCI, and 181 underwent CABG. Surgical patients had higher rates of left main disease, triple-vessel disease, peripheral vascular disease, emergent procedures, and previous myocardial infarctions (39.7% versus 3.3% [P = .001], 76.1% versus 28.3% [P = .0001], 19.6% versus 7.5% [P = .004], 15.8% versus 2.5% [P = .0001], and 35.9% versus 25% [P = .04], respectively). CABG patients had a higher early mortality rate (9.9% versus 2.5%, P = .01). There were no differences in 1- and 4-year actuarial survival rates, with rates of 90% and 68%, respectively, for the PCI group and 85% and 71% for the CABG group (P = .85). The rates of actuarial freedom from major adverse cardiac events (MACEs) at 1 and 4 years were 83% and 75%, respectively, for the PCI group, and 86% and 78% for the CABG group (P = .33). The respective rates of freedom from reintervention were 87% and 83% for the PCI group, versus 99% and 97% for the CABG group (P < .001). The 4-year rate of freedom from recurring angina was 58% for the PCI group, versus 88% for CABG patients (P < .001). Revascularization strategy was not a predictor of adverse outcome in a multivariable analysis.Conclusion: Octogenarian CABG patients were sicker and experienced a higher rate of early mortality. The 2 strategies had similar rates of late mortality and MACEs, with fewer reinterventions and recurring angina occurring following surgery.     

The effect of growth hormone on the development of diabetic kidney disease in rats.

BACKGROUND: Nephropathy is the most severe complication of diabetes mellitus. We investigated the effect of exogenous growth hormone (GH) administration on renal function and matrix deposition in the streptozotocin (STZ) model of type I-diabetic rat. METHODS: Adult female STZ-diabetic rats (D), non-diabetic control rats injected with saline (C) and control and diabetic rats injected with bovine GH for 3 months (CGH and DGH, respectively) were used. RESULTS: The usual renal hypertrophy seen in D animals was more pronounced in the DGH group. Creatinine clearance increased only in the D rats, but not in the other groups, including DGH. Albuminuria was observed in the D animals but was significantly elevated in the DGH group. Glomeruli from DGH animals showed more extensive matrix accumulation (manifested as an increase in mesangial/glomerular area ratio). Renal extractable insulin-like growth factor (IGF-I) mRNA was decreased in the D and DGH groups, but renal IGF-I protein was not significantly increased. Renal IGF binding protein-1 was increased in the D groups and further increased in the DGH group, at both the mRNA and protein levels. CONCLUSIONS: GH-treated diabetic rats had less hyperfiltration and more albuminuria, concomitant with more glomerular matrix deposition, when compared with regular diabetic animals. This was associated with a significant increase in renal IGFBP-1, and dissociated from IGF-I changes. Thus, in this model, GH exacerbates the course of diabetic kidney disease.