Effects of overexpansion on stents' recoil, symmetry/asymmetry, and neointimal hyperplasia in aortas of hypercholesterolemic rabbits.

BACKGROUND: It is not known whether overexpansion modifies stent recoil, symmetric distribution of struts, and neointimal hyperplasia. OBJECTIVES: The objectives were (a) to evaluate whether stent overexpansion modifies the geometric configuration of the stent in the arterial wall, (b) to determine the relationship between overexpansion and stent recoil, and (c) to evaluate the relationship between the distribution of struts and neointimal hyperplasia. METHODS: Twenty tubular stainless steel 316L stents (3.0 and 3.5 mm in diameter) were implanted at 20 and 10 atm, respectively, in the abdominal aorta of New Zealand rabbits fed a hypercholesterolemic diet (1% cholesterol). Sham operations were also performed in seven animals. Eight weeks after implantation or sham operation, an intravascular ultrasound (IVUS) study was performed to measure stent recoil and aid in stent classification (symmetric or asymmetric) according to strut distribution. The degree of injury and neointimal hyperplasia were also evaluated in hematoxylin-eosin stained sections. RESULTS: The symmetry/asymmetry of stents assessed by IVUS, as well as the neointimal hyperplasia, was similar in both groups. Stent recoil was significantly greater in the 3.0-mm stent (overexpanded) group (0.28+/-0.02 mm), as compared with stent recoil in the 3.5-mm stent group (0.10+/-0.01 mm, P<.05). The neointimal hyperplasia in histological slices, independent of the implant technique, was predominantly in zones with higher strut concentration as compared with zones with fewer struts. CONCLUSIONS: Stent overexpansion enhanced stent recoil and did not modify symmetric and asymmetric strut distribution. Neointimal hyperplasia was not modified by the implant technique. Interestingly, significant hyperplasia was observed in locations with greater strut concentration, independent of overexpansion.     

Multidisciplinary protocol of preoperative and surgical management of patients with pituitary tumors candidates to pituitary surgery

The optimal planning of preoperative diagnosis, management and treatment of pituitary tumors (PT) candidates to pituitary surgery (PS) requires a multidisciplinary approach involving a team of endocrinologists, neurosurgeons, ENT, neuro-ophthalmologists and neuroradiologists with experience in pituitary diseases. Such teams improve surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological and radiological preoperative and follow-up evaluation. We have developed a clinical practice protocol for patients with PT who are candidates to PS based on the most recent national and international guidelines and the relevant literature regarding PT published in the last years. The protocol has been elaborated by a multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the perioperative and surgical management of PT thereby facilitating the management of patients undergoing PS.     

Blefarospasmo y espasmo hemifacial: tratamiento a largo plazo con toxina botulínica

Introduction

Our purpose is to describe the demographic, clinical and therapeutic characteristics of patients with blepharospasm (BS) and hemifacial spasm (HFS) in treatment with botulinum toxin type A (BtA).

Patients and methods

Retrospective analysis of patients diagnosed with BS or HFS and treated with BtA in the Neurology Department at Complejo Asistencial de Segovia between March 1991 and December 2009.

Results

Different variables were collected from 34 patients with BS and 55 with HFS, of whom 44.1% and 32.7% respectively had been undergoing treatment with BtA for more than 10 years. Elapsed time from symptom onset to the first visit was 24 months in the BS group and 59.7 months in the HFS group. Diagnosis was given on the first visit for 76.5% of the BS patients and 90.7% of the HFS patients. Patients were referred by their primary care centres in 34.6% of the cases with BS and in 77.6% of the cases with HFS. The most commonly used BtA preparation was BOTOX^® in both groups, and there were no cases of primary or secondary resistance. The median dose of BtA was raised gradually in both groups, and the increase was statistically significant during the early years of treatment. The most common side effect was ptosis (47.1% in BS, 32.5% in HFS).

Conclusions

BS and HFS are the most common facial movement disorders. The demographic and clinical characteristics and therapeutic findings from this study show that treatment with BtA is both effective and safe over the long term.     

Factors associated with silent myocardial ischemia,autonomic or peripheral neuropathies,and survival in diabetes mellitus type 2 patients without cardiovascular symptoms

International Journal of Diabetes in Developing Countries - Complications from diabetes mellitus (DM) include cardiovascular system, peripheral neuropathy (PN), and autonomic dysfunction (AD)....     

Irinotecan-eluting stents inhibited neointimal proliferation in hypercholesterolemic rabbit aortas.

OBJECTIVE: To assess the effect of irinotecan-eluting stents (IS) on neointimal growth in the aortas of hypercholesterolemic rabbits and to determine other local histopathological effects such as necrosis, fibrin, and inflammatory reaction. METHODS: Phosphorylcholine-coated stents were deployed in the aortas of hypercholesterolemic rabbits. Group 1 (control; n = 8) received unloaded stents, group 2 (n = 7) and group 3 (n = 9) received IS with 0.046 mg and 1.29 mg of irinotecan, respectively. Eight weeks after implantation the rabbits were killed. Neointimal thickness (NT) was assessed by morphometry. Semiquantitative injury score (from 0 to 3+) was used to analyze inflammatory infiltrate, fibrin deposits, and necrosis in the stented segments. RESULTS: NT was reduced only in high-doses IS (G1, 167.4 +/- 20.8 mu; G2, 170.24 +/- 21.2 mu; G3, 111.56 +/- 12.7 mu; P < 0.05, G3 vs G1 and G2). Necrosis decreased significantly with IS [1.00 +/- 0.10 in G1 to 0.33 +/- 0.07 and 0.02 +/- 0.01 in G2 and G3, respectively] only in the media layer. The inflammatory infiltrate was present in the three layers of aortas from G1, but only decreased significantly in the intimae layer of the high-dose group [1.50 +/- 0.15 in G1 vs 1.00 +/- 0.18 in G3, P < 0.05]. CONCLUSION: Stents loaded with high-dose irinotecan inhibit NT in the aortas of hypercholesterolemic rabbits. This effect was accompanied by decreased inflammatory infiltrate and media necrosis.     

Diseño de una nueva herramienta para la exploración auditiva

IntroductionMany presbycusic patients have difficulty in understanding certain words. This could be justified because certain sounds in Spanish are more difficult to perceive, particularly the sounds with energy in the high frequencies. We propose to use a sentence as a tool to check this theory.Materials and methodAll the Spanish sounds were analyzed, measuring the degree of acoustic energy in all the frequencies. The conclusions drawn from the comparison of the results allowed the design of the tool that is proposed here.ResultsWe established a gradient of perception difficulty, occlusive consonants being the least perceptible, followed by fricative, and finally all those segments with harmony and a clear formant structure. The Spanish sentence “Ana vio ese coche rojizo fino” is proposed as the tool for this study. This sentence has some as it comprises certain peculiarities that makes it particularly useful for this purpose. It will allow us to check whether understanding deteriorates as we move from beginning to end, helping evaluate the importance of high frequencies for intelligibility.ConclusionsA positive result could help in the design of amplification systems to improve speech intelligibility. In addition, the exploratory tool could allow neuro-acoustic exploration, useful in the central auditory pathology studies.