Orbital Complications of Sinusitis in the Aspirin Triad Syndrome

Orbital complications are uncommon in adult sinusitis. In contrast, the sinusitis of the aspirin triad syndrome is often fulminate, expansive, and recurrent, and complications may be more frequent. Of 81 patients with aspirin triad who were treated surgically, 7 patients (8.6%) had orbital complications, including sinus mucoceles in 3 patients, lacrimal gland extension in 2 patients, inflammatory orbital mass in 1 patient, and proptosis from expansile sinonasal polyposis in 1 patient. All complications manifested within 2 years of prior surgery. Two patients suffered blindness. In a group of 120 consecutively treated sinus surgery patients without aspirin triad syndrome (51 of whom were followed for more than 2 years), no patient manifested nonoperative orbital complications. The results of this study suggest that aspirin triad patients are at significant risk for orbital complications and therefore should have long-term follow-up with aggressive treatment of persistent disease.     

Revascularization in severe ventricular dysfunction (15% ≤ LVEF ≤ 30%): a comparison of bypass grafting and percutaneous intervention

Background

We sought to determine the optimal approach to revascularization of patients with severe left ventricular (LV) dysfunction.

Methods

We conducted a single-center observational study of 117 consecutive patients who had severe LV dysfunction (15% ≤ LV ejection fraction ≤ 30%) and underwent either coronary artery bypass grafting (CABG, n = 69) or percutaneous revascularization (n = 48) between 1992 and 1997.

Results

The CABG group was younger (62 versus 67 years, p = 0.026), and fewer previous bypasses (7% versus 40%, p < 0.0001) and fewer prior percutaneous revascularizations (16% versus 42%, p = 0.0019) were noted. More vessels were revascularized (3 ± 0.8 versus 1.5 ± 0.7, p < 0.0001), and revascularization was more complete by CABG (84% versus 48%, p < 0.0001). Morbidity and mortality at 30 days were similar, and there was no significant difference in 3-year survival (73% versus 67%), although 3-year cardiac event-free survival (52% versus 25%, p = 0.0011) and 3-year target vessel revascularization-free survival (71% versus 41%, p < 0.0001) were significantly better in the CABG group, and LV ejection fraction was significantly improved after CABG. In the subgroup of patients 65 years of age or older and those without proximal left anterior descending coronary artery lesions, significant benefit of CABG in cardiac event-free and target vessel revascularization-free survival disappeared.

Conclusions

We found that in clinically selected patients with severe ventricular dysfunction, CABG compared with percutaneous revascularization achieves more complete revascularization, improved LV function, fewer cardiac events, and fewer target vessel revascularizations, but does not affect mid-term survival. A prospective controlled trial with defined criteria for treatment assignment is warranted to confirm our results regarding the two revascularization strategies in patients with severe LV dysfunction.     

利尿酸是打开血-迷路屏障的钥匙

目的观察在不同的时机应用利尿酸以暂时破坏耳蜗血管纹上皮是否能够开放血-迷路屏障,从而促使庆大霉素进入耳蜗或者从耳蜗排出.方法听神经动作电位测试技术,全耳蜗毛细胞计数定量观察技术和荧光偏振免疫法测定庆大霉素浓度的技术被用于以下两个不同目的的实验观察.(1)当庆大霉素血中浓度高于内耳液浓度时,应用利尿酸破坏蜗管外壁以促使更多的庆大霉素进入耳蜗以制备不同程度耳蜗损害的动物模型.(2)当庆大霉素内耳浓度高于血中浓度时,应用利尿酸损坏蜗管外壁以促使蓄积在耳蜗内的庆大霉素从内耳排出以达到挽救毛细胞的目的.结果1.当庆大霉素血中浓度高于内耳液浓度时,注射利尿酸可造成更多的毛细胞损害和听功能障碍,外淋巴中药物的峰值浓度和半衰期浓度也均比单独一次注射庆大霉素动物外淋巴中药物浓度增加一倍,说明同时注射利尿酸可促使更多的庆大霉素从血液进入耳蜗并造成更严重的毛细胞损害.2.当血液中庆大霉素排空之后,注射利尿酸可减少毛细胞数量的损失程度,同时发现延迟注射利尿酸组动物的听力损失程度比不经利尿酸处理动物组有所减轻,外淋巴中药物浓度也比不经利尿酸处理动物组降低一半,说明当GM在耳蜗内蓄积但血清中已经排空时注射EA有助于降低药物在耳蜗内的蓄积并挽救尚未被破坏的毛细胞.结论利尿酸可以做为打开血-迷路屏障的钥匙,但是应用利尿酸开放血-迷路屏障可以产生双向结果,其关键在于注射利尿酸的时机.     

Sex differences in auditory sensitivity of chinchillas before and after exposure to impulse noise

OBJECTIVE: To determine if chinchillas exhibit sex differences in 1) basic auditory sensitivity and 2) susceptibility to cochlear damage and hearing loss from high-level impulse noise. DESIGN: The auditory sensitivity of 73 chinchillas was assessed by measuring evoked potentials from electrodes implanted in the inferior colliculus (IC-EVPs) and cubic (2f1-f2) distortion product otoacoustic emissions (CDPs). A subgroup of 16 chinchillas were retested after exposure to simulated M16 rifle fire (150 dB pSPL impulse noise). Thresholds and postexposure temporary and permanent threshold shifts were compared as a function of sex and frequency using analysis of variance procedures. Cochleograms, showing the percent of hair cells missing as a function of location on the basilar membrane, were constructed to show inner hair cell (IHC) and outer hair cell (OHC) losses for each group. RESULTS: Female chinchillas had slightly lower high-frequency thresholds, and slightly higher low-frequency thresholds than male chinchillas, but similar IC-EVP and CDP amplitude functions. Significant sex differences were observed after exposure to high-level impulse noise. Overall, female chinchillas developed approximately 10 dB more high-frequency hearing loss, but approximately 5 dB less low-frequency hearing loss than males. Hair cell losses, particularly IHC losses, were substantially less for females as compared with males. CONCLUSIONS: The results point to close similarities between chinchillas and humans with regard to sex/gender differences in basic auditory sensitivity before noise exposure, suggesting that the chinchilla may be a good model for exploring the anatomical and physiological bases of these differences. In addition, the results show significant sex differences in the physiological and anatomical response of the chinchilla cochlea to high-level noise. Similar differences in humans could have important implications with regard to military assignments and hearing conservation programs.     

The pathobiology of acute asthma

Acute bronchial asthma is a common problem with immense medical and economic impacts. It is estimated that this disease affects 12 to 14 million people in the United States with costs in excess of $6 billion per year. Most of the morbidity and all of the mortality of asthma tends to be associated with acute exacerbations, and treatment of these events accounts for the majority of expenditures in money and health care resources. Unfortunately, the factors that contribute to the destabilization of asthma are rarely studied and much of the pathogenesis and pathobiology of acute asthma remains unknown. This article examines these issues and suggests treatment for acute asthma.     

Principles of radiographic exposure a new approach

Radiographic technique charts have traditionally been established by the empirical method. A precisely calculated chart based on the effective energy of the spectrum and the output of the equipment will give more consistent results of density and contrast as well as repeatability of these results from patient to patient. A better understanding of patient attenuation and screen energy sensitivity will enable the radiographer to logically adjust technical factors to change density or contrast scales as required.