Experience with intraoperative high frequency Doppler sonography in neurosurgical practice

Abstract

The method of blood flow velocity (BFV) evaluation by intraoperative application of the high frequency Doppler is presented. The device is used to estimate BFV changes in small caliber arteries by direct placement of the probe upon the examined vessel. BFVexaminations were performed on the site during aneurysm operations, during transsphenoidal approaches to identify the intracavernous portion of leA embedded in the tumor mass and in patients after encephalodurosynangiosis evaluated on the outpatient basis. Technical characteristics of the flowmeter used are described and examples of the BFV pictures in cerebral arteries are presented. The device allows a precise BFVevaluation in the selected vessel and detection of changes in BFV patterns particularly useful during aneurysms surgery. This method of identifying cerebral vessels may become applicable in other types of neurosurgical operations. [Neural Res 1998; 20: 655–657]     

Microbiological effects in patients with leg ulcers and diabetic foot treated with Lucilia sericata larvae

Lucilia sericata bottle fly worms can be used to heal infected, chronic, or necrotic wounds, including those associated with ulceration and diabetic foot. The study aimed to evaluate changes in the microflora in patients treated with L sericata larvae due to leg ulcers and diabetic foot. One hundred twenty-nine patients diagnosed with lower limb ulceration and diabetic foot were enrolled in the study, of which 80 of them met the eligibility criteria for maggot debridement therapy (MDT). On the contrary, 49 unqualified patients were offered ozone therapy (22 with leg ulcers; 27 with diabetic foot). In each of these patients, a microbiological swab was performed before and after the start of therapy. The group of 80 patients was further divided into four equal groups in terms of the treated area (lower leg vs foot) and the number of larvae/cm² (5 vs 10). Twenty-three particular species of bacteria in the infected wound were studied microbiologically in terms of presence/absence within the wound environment before and after treatment of patients with diabetic foot and lower limb ulceration. It was noted that there was a more intensive bacterial accumulation in the feet of patients compared to legs; furthermore, this applies to almost all analysed species. Diabetes status is also a clinical factor that generates a lower chance of bacterial appearance in the wound environment. Densification of MDT larvae per wound area unit also reduced the chance of the presence of Corynebacterium species, Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcus aureus MSSA, and Streptococcus coagulase negativa; however, it increased the likelihood of occurrence for Proteus mirabilis and the Proteus species. A microbiological analysis in this non-reference study shows the efficacy of larval therapy for leg and foot ulcers. Rearrangement of the microflora within the wound has been reported as a result of the therapy.     

Radiosynthesis of microtubule‐targeted theranostic methyl N‐[5‐(3’‐radiohalobenzoyl)‐1H‐benzimidazol‐2‐yl]carbamates

Microtubules are a target for a broad spectrum of drugs used as chemotherapeutics to treat hematological malignancies and solid tumors. Most of these drugs have significant dose‐limiting toxicities including peripheral neuropathies that can be debilitating and permanent. In an ongoing effort to develop safer and more effective drugs, benzimidazole‐based compounds are being developed as replacement for vincristine and similar agents. In this report, we describe radiosyntheses of novel microtubule‐targeting methyl N‐[5‐(3’‐radiohalobenzoyl)‐1H‐benzimidazol‐2‐yl]carbamates 4 that are intended as potential imaging agents and molecular radiotherapeutics. ¹²⁵I‐ and ¹³¹I‐radiolabeled derivatives were prepared either by direct radioiodination of methyl N‐(6‐benzoyl‐1H‐benzimidazol‐2‐yl)carbamate 1 or radioiododestannylation of the corresponding stannane precursor 3 . The direct radioiodination was conducted in a solution of 1 in triflic acid and produced after ~1 hour at elevated temperatures and HPLC purification on average 62% of the no‐carrier added products ¹²⁵I‐ 4 and ¹³¹I‐ 4 . Radioiododestannylation of 3’‐trimethylstannane 3 proceeded with ease at room temperature in the presence of H₂O₂ as the oxidant and produced no‐carrier‐added ¹²⁵I‐ 4 and ¹³¹I‐ 4 in high isolated yields, on average 85%. The radiohalodestannylation protocol is universal and can be applied to other radiohalides including ¹²⁴I to produce ¹²⁴I‐ 4 , a positron emission tomography agent, and ²¹¹At to produce ²¹¹At‐ 4 , an α‐particle emitting radiotherapeutic.     

Influence of reciprocating tachycardia on the development of atrial fibrillation in patients with preexcitation syndrome

BACKGROUND: We sought to evaluate the influence of atrio-ventricular reentrant tachycardia (AVRT) on atrial pressures during tachycardia and the presence of atrial fibrillation (AF) in patients with preexcitation syndrome. METHODS: The study population consisted of 88 patients (37 females, mean age 37.3 years) with left-sided accessory pathway and AVRT induced during electrophysiologic study. The AF-inducible group consisted of 32 patients with sustained episodes of AF provoked during electrophysiologic study, whereas the noninducible group comprised 56 patients without AF. RESULTS: We found significantly higher values of maximal and mean left (LAP) and right (RAP) atrial pressures in the AF group compared with noninducible group: LAP max 32.0 versus 20.8, LAP mean 21.6 versus 13.2, RAP max 15.2 versus 11.5, RAP mean 8.2 versus 6.2 respectively (P < 0.001). When analyzing the effect of AVRT on atrial pressures, we found a significant (P < 0.001) negative correlation between anterograde conduction times during tachycardia and LAP max and LAP mean in the whole population, but a significant positive correlation between retrograde conduction time and left atrial pressures. Similar effects of AVRT on the right atrial pressures were found. CONCLUSIONS: Atrial pressures during AVRT, which depend on the electrophysiological features of tachycardia, play an important role in the genesis of atrial fibrillation in patients with preexcitation syndrome.     

Influence of comorbidities and medication use on tilt table test outcome in elderly patients

BACKGROUND: The tilt table test (TTT) is a useful diagnostic tool in people with unexplained syncope, dizziness, and falls. However, preexisting comorbidities and medications affecting hemodynamic response might affect TTT outcome (i.e. presence or absence of vasomotor syncope). We studied the influence of these compounding factors on TTT outcome. METHODS: One hundred and sixty-four elderly patients with a mean (+/-SD) age of 80.0 +/- 6.1 years (M:F 104:60) underwent TTT. Heart rate and blood pressure were recorded continuously using a noninvasive device (Task Force Monito, CNS systems, Graz, Austria). Predictors of TTT outcome in a backward regression analysis included age, gender, comorbidities (chronic heart failure, hypertension, diabetes, and cerebrovascular disease), and drugs (beta-blockers, angiotensin-converting enzyme inhibitors, calcium channel blockers, diuretics, digoxin, opioids, antidepressants, and nonsteroidal antiinflammatory agents). RESULTS: TTT was positive in 30 patients (18.3%). None of the above factors were a significant predictor of TTT outcome. The use of calcium channel blockers predicted a drop in systolic blood pressure after 2 minutes of TTT (P = 0.048, R(2)= 0.018). However, this was not associated with significant changes in heart rate and did not influence TTT outcome. CONCLUSION: The TTT outcome was not influenced by comorbidities or medications. TTT is a reliable diagnostic tool in a population characterized by significant comorbidities and polypharmacy.     

Lithium disturbs homeostasis of essential microelements in erythrocytes of rats: Selenium as a protective agent?

Background

Selenium is an essential element which shows protective properties against diverse harmful factors. Lithium compounds are widely used in medicine, but, in spite of undoubted beneficial effects, treatment with these compounds may lead to severe side effects, including renal, gastrointestinal, neurological, endocrine and metabolic disorders. This study was aimed at evaluating the influence of selenium and/or lithium on lithium, iron, zinc and copper content in rats’ erythrocytes as well as estimate the action of additional selenium on lithium exposure effects.

Ceramic Biomaterial Pores Stereology Analysis by the Use of Microtomography

The main aim of this study was to analyze microtomographic data to determine the geometric dimensions of a ceramic porous material’s internal structure. Samples of a porous corundum biomaterial were the research material. The samples were prepared by chemical foaming and were measured using an X-ray scanner. In the next stage, 3D images of the samples were generated and analyzed using Thermo Scientific Avizo software. The analysis enabled the isolation of individual pores. Then, the parameters characterizing the pore geometry and the porosity of the samples were calculated. The last part of the research consisted of verifying the developed method by comparing the obtained results with the parameters obtained from the microscopic examinations of the biomaterial. The comparison of the results confirmed the correctness of the developed method. The developed methodology can be used to analyze biomaterial samples to assess the geometric dimensions of biomaterial pores.