Protection of the C1 posterior arch in atlantal lateral mass fixation: technical case report.

Screw fixation of the C1 lateral mass is a relatively new technique designed to allow for C1/C2 fixation in scenarios where transarticular screw fixation is not safe or possible. In order to place the screw at the base of the C1 arch, it has been recommended to drill at the junction of the C1 posterior arch and the lateral mass of C1, to accommodate the screw head. This may, however, weaken the C1 arch, making it prone to fracture. In this new technique, we describe a modification to the current technique to allow placement of this screw without compromising the C1 arch. A case of atlantoaxial instability secondary to os odontoideum is described. C1 lateral mass fixation is achieved by selecting a screw 10 mm longer than required and placing the screw 10 mm above the bony entry point, for easier placement of the rod and avoidance of drilling at the base of the C1 arch. Adequate and safe C1/C2 fixation was achieved. Sublaminar wiring was performed around the C1 arch with no weakening or fracture of the arch. We believe that in order to place reasonable C1 lateral mass screws, it is inadvisable to drill the base of the junction between the C1 posterior arch and lateral mass as this may lead to arch weakening and failure. Easier instrumentation can be performed and the integrity of the C1 arch maintained using this alternate technique.     

Interindividual differences in personality and behavior and subjective health problems in shift workers]

A total of 604 experienced shift workers were administered a battery of questionnaires in order to examine the relationships between the shift workers' features and subjective health complaints taken as signs of intolerance to shift work. The individual difference measures included: hard-driving and competitiveness, speed and impatience, relaxed, efficiency, flexibility of behaviour, evening, rigidity of sleeping habits, vigorous, languidness, inveterate, flexibility of habits, neuroticism, extraversion, lie-scale, age and work experience. The subjective health complaints included: generally poor health, musculo-skeletal, respiratory and psychosomatic-digestive complaints, and digestive problems. Correlation and multiple regression analyses showed that in workers some personality features and patterns of behaviour were related to the subjective health complaints. More health complaints were placed by workers who were emotionally unstable, less relaxed, inefficient, rigid (e.g. unable to control the behavioral arousal level), hard-driving and competitive, speedy and impatient (A-types), rigid in sleeping and other life habits, languid, older and with longer shift work experience.     

Shift work and health problems in workers

A comparative study of health complaints was performed in a large oil-refinery among a total of 609 shift workers and 97 non-shift workers. Health complaints were assessed on the basis of the workers' medical records, where details of every visit to the physician over a period of five years were noted, and as subjective health complaints obtained by a questionnaire. In general, the non-shift workers visited the physician more often than the shift workers. However, when visits to the physician for special groups of diseases were considered taking into account the overall number of visits, and especially when the subjective health complaints were compared between the two groups of workers, the results indicated that the shift workers were at greater risk of some diseases, especially the digestive ones.     

Magnetic resonance imaging clarity of the Bryan, Prodisc-C, Prestige LP, and PCM cervical arthroplasty devices

STUDY DESIGN: Prospective, randomized, controlled and double-blinded study on imaging of artificial discs. OBJECTIVE: The purpose of this study is to compare postoperative imaging characteristics of the 4 currently available cervical arthroplasty devices at the level of implantation and at adjacent levels. SUMMARY OF BACKGROUND DATA: Cervical arthroplasty is being performed increasingly frequently for degenerative disc disease and, in most cases, with frank neural compression. Unlike lumbar arthroplasty, performed mainly for axial back pain, decompression of neural elements may need to be confirmed with postoperative imaging after cervical arthroplasty. METHODS: Preoperative and postoperative magnetic resonance imaging scans of 20 patients who had undergone cervical arthroplasty were assessed for imaging quality. Five cases each of the Bryan (Medtronic Sofamor Danek, Memphis, TN), Prodisc-C (Synthes Spine, Paoli, PA), Prestige LP (Medtronic Sofamor Danek), and PCM devices (Cervitech, Rockaway, NJ) were analyzed. Six blinded spinal surgeons scored twice sagittal and axial T2-weighted images using the Jarvik 4-point scale. Statistical analysis was performed comparing quality before surgery and after disc implantation at the operated and adjacent levels and between implant types. RESULTS.: Moderate intraobserver and interobserver reliability was noted. Preoperative images of patients in all implant groups had high-quality images at operative and adjacent levels. The Bryan and Prestige LP devices allowed satisfactory visualization of the canal, exit foramina, cord, and adjacent levels after arthroplasty. Visualization was significantly impaired in all PCM and Prodisc-C cases at the operated level in both the spinal canal and neural foramina. At the adjacent levels, image quality was statistically poorer in the PCM and Prodisc-C than those of Prestige LP or Bryan. CONCLUSIONS.: Postoperative visualization of neural structures and adjacent levels after cervical arthroplasty is variable among current available devices. Devices containing nontitanium metals (cobalt-chrome-molybdenum alloys in the PCM and Prodisc-C) prevent accurate postoperative assessment with magnetic resonance imaging at the surgical and adjacent levels. Titanium devices, with or without polyethylene (Bryan disc or Prestige LP), allow for satisfactory monitoring of the adjacent and operated levels. This information is crucial for any surgeon who wishes to assess adequacy of neural decompression and where monitoring of adjacent levels is desired.     

Ratiometric spectral imaging for fast tumor detection and chemotherapy monitoring in vivo

We report a novel in vivo spectral imaging approach to cancer detection and chemotherapy assessment. We describe and characterize a ratiometric spectral imaging and analysis method and evaluate its performance for tumor detection and delineation by quantitatively monitoring the specific accumulation of targeted gallium corrole (HerGa) into HER2-positive (HER2 +) breast tumors. HerGa temporal accumulation in nude mice bearing HER2 + breast tumors was monitored comparatively by a. this new ratiometric imaging and analysis method; b. established (reflectance and fluorescence) spectral imaging; c. more commonly used fluorescence intensity imaging. We also tested the feasibility of HerGa imaging in vivo using the ratiometric spectral imaging method for tumor detection and delineation. Our results show that the new method not only provides better quantitative information than typical spectral imaging, but also better specificity than standard fluorescence intensity imaging, thus allowing enhanced in vivo outlining of tumors and dynamic, quantitative monitoring of targeted chemotherapy agent accumulation into them.     

Evaluation of multiple measures of antiretroviral adherence in the Eastern European country of Georgia

Introduction

There is little information on adherence to antiretroviral therapy (ART) in the Eastern European region. This prospective study evaluated multiple measures of adherence and their association with viral suppression among HIV patients in Georgia.

Methods

A prospective cohort study enrolled 100 consecutive antiretroviral-naïve adult (age ≥18 years) patients, who were followed for three months. Adherence was assessed by medication refill and three self-report measures (an AIDS Clinical Trial Group [ACTG] tool for four-day adherence, a visual analogue scale [VAS] and a rating task for 30-day adherence). The VAS represented a line anchored by 0 and 100% corresponding to the percentage of prescribed doses taken. The rating task asked patients to rate their ability to take all medications as prescribed, with responses categorized into six levels of adherence: very poor (0%), poor (20%), fair (40%), good (60%), very good (80%) and excellent (100%). Patients with adherence of ≥95% by medication refill, ACTG and VAS, and ≥80% by rating task, were defined as adherent.

Results

Of 100 patients enrolled, eight had missing data and were excluded from analysis. Among the remaining 92 patients, the median age was 39 years, and 70% were men. Major modes of HIV acquisition were injection drug use (IDU; 47.3%) and heterosexual contact (44.1%). The proportions of adherent patients were as follows: 68% by medication refill, 90% by ACTG questionnaire, 38% by VAS and 42% by rating task. On average, four months after commencing ART, 52 (56.5%) patients had a viral load <400 copies/ml and 26 (28.3%) patients had a viral load <50 copies/ml. Of 43 persons with a history of IDU, 22 (51.2%) reached a viral load of <400 copies/ml. In multivariate analysis, only refill adherence was a statistically significant predictor of viral suppression of <400 copies/ml: the risk ratio was 1.7 (95% CI: 1.1–2.8). Refill adherence, VAS and rating task were associated with viral suppression of <50 copies/ml. Non-IDUs were twice as likely to achieve viral load <50 copies/ml compared to IDUs. Refill adherence had the largest area under the receiver-operating characteristic curve for predicting viral suppression.

Conclusions

Medication refill adherence was the strongest predictor of viral suppression. IDUs can achieve optimal virologic outcomes, but may require additional adherence support.