No abstract

In this study, the cinegraphic image intensifier entrance dose level for coronary angiography was changed in four steps from dose level A (0.041 microGy frame(-1)), allowing high contrast, but coarse mottled background, to level D (0.164 microGy frame(-1)), affording high transparency and sharpness. Using this new approach throughout the course of 404 consecutive cardiac catheterizations, we reduced patient radiation exposures down to 11 to 16% of currently typical values: i.e., mean dose area products of 5.97 Gy cm2 (n = 91), 6.73 (n = 113), 8.11 (n = 91), and 8.90 (n = 109); cinegraphic dose area products of 2.34, 3.64, 4.56, and 5.49; and cinegraphic dose area products frame(-1) of 13.3, 19.8, 27.0, and 30.2 mGy cm2, for levels A, B, C, and D, respectively. The number of cinegraphic frames ranged within 168 to 182 per case. Our results show that during catheterization interventionalists should vary image intensifier entrance dose levels in accordance with documented structure, angulation, and body mass index. With the exception of cases with special requirements, lower dose levels typically guarantee an adequate image quality.

The objective of this study was to investigate the influence of time of day on patient radiation exposure due to cardiac interventions. The elective interventional workload of one experienced cardiologist documented over the course of 4 months amounted to 325 diagnostic catheterizations and 145 percutaneous coronary interventions (PCI). All radiation parameters documented during diagnostic coronary angiography remained constant throughout the entire day. In contrast, for PCI measurements made from 7:00 a.m. to 1:00 p.m., our study revealed a mean overall dose-area product (DAP) of 11.8+/-6.8 Gy cm(2) (n=115). These radiation exposure levels increased significantly later in the afternoon (n=30) by 28% to a level of 15.0+/-11.1 Gy cm(2) (p<0.045). Cinegraphic DAP increased from 3.7+/-2.7 Gy cm(2) to 5.0+/-3.2 Gy cm(2) (p<0.033). The number of cinegraphic runs and frames rose from 7.9+/-2.9 to 9.1+/-3.1 (p<0.025), and from 136+/-63 to 164+/-70 (p<0.014), respectively. The following conclusion is warranted by our data and should now be confirmed in a wider multicentre study: radiation protection of the patients could be influenced by the fatigue of the cardiologist conducting the procedure. To enhance patient radiation safety, elective percutaneous angioplasty should be scheduled for the first 6 h of the interventionalist's occupational workload. Diagnostic interventions may be safely scheduled later.

Purpose Convergence spasm (CS, spasm of near reflex) is characterized by transient attacks of convergence, miosis and accommodation, often associated with functional neurological disorders. To date, no simple and efficient treatment option is available for CS. This study investigates whether periorbital botulinum toxin injections as used in essential blepharospasm are also a treatment option in these patients. Methods All patients with convergence spasm having been treated with periorbital BoNTA injections in the department of neuro-ophthalmology were identified. Data were extracted from patient files concerning details and subjective effectiveness of botulinum toxin injections and relation to psychiatric or neurological disorders. Patients reporting with a history of closed-head trauma or organic neurologic pathologies possibly causing CS were excluded. A telephone assessment with a standardized questionnaire was performed to evaluate mental health issues as a trigger, as well as the long-term effect and satisfaction with periorbital injections. Results Of 16 patients treated with periorbital botulinum toxin injections for convergence spasm, 9 patients reported depression and/or anxiety disorders ongoing or in the past. A median number of 3 injections (range 1–13) was administered with a variable effect (relief of symptoms) between no effect and effect of up to more than 12 weeks. A longitudinal follow-up revealed ongoing symptoms in five patients. Conclusions Periorbital botulinum toxin injections are less invasive than injections in the medial rectus muscle and can be a bridging therapeutic option in patients with CS. Mental health exploration is important due to psychiatric comorbidity.