Paths of thoracic epidural catheters in children undergoing the Nuss procedure for pectus excavatum repair.

PURPOSE: To investigate the paths of thoracic epidural catheters in children, this retrospective study was performed. METHODS: We investigated 73 children aged 4 to 12 (mean ± SD 7.8 ± 2.3) years, who underwent the Nuss procedure for pectus excavatum repair under combined general and epidural anesthesia over a 5-year period at Tokyo Metropolitan Police Hospital. Following induction of general anesthesia, we inserted a radiopaque epidural catheter via the T5/6 or T6/7 interspace and advanced for 5 cm cephalad in the thoracic epidural space. We evaluated the paths of the epidural catheters on plain chest radiographs after surgery. RESULTS: The median level for the catheter tip location was T3 (range C6-T7), while the median number of vertebrae crossed by the catheter tips was 2.5. In most children, the catheters advanced straight for the first 2-3 cm (1-1.5 vertebrae) in the thoracic epidural space. However, they continued to advance straight in only 25 children, while they exhibited curved or coiled paths in the remaining 48. The catheter tips were located at higher levels in children with straight epidural catheter paths [median (range) T2 (C6-T4)] than in those with curved or coiled paths after the initial 2-3 cm [median (range) T4 (T2-T7)] (p < 0.0001). CONCLUSIONS: Our findings indicate that the course of epidural catheters in children is unpredictable after the first 2-3 cm in the thoracic epidural space. Clinicians should be aware of such findings, although further studies are required for confirmation.

Role of chemical potential in relaxation of faceted crystal structure.

Below the roughening transition, crystal surfaces have macroscopic plateaus, facets, whose evolution is driven by the microscale dynamics of steps. A long-standing puzzle was how to reconcile discrete effects in facet motion with fully continuum approaches. We propose a resolution of this issue via connecting, through a jump condition, the continuum-scale surface chemical potential away from the facet, characterized by variations of the continuum surface free energy, with a chemical potential originating from the decay of atomic steps on top of the facet. The proposed condition accounts for step flow inside a discrete boundary layer near the facet. To validate this approach, we implement in a radial geometry a hybrid discrete-continuum scheme in which the continuum theory is coupled with only a few, minimally three, steps in diffusion-limited kinetics with conical initial data.

[Usefulness of ultrasound sonography in performing posterior sacroiliac ligament injection in elderly patients].

BACKGROUND: The sacroiliac joint (SIJ) is recognized as a potential source for low back pain especially in elderly people. Previous studies indicated that in patients with SIJ pain, posterior sacroiliac ligament injections are more effective than intra articular injections. The aim of this study was to assess usefulness of ultrasound sonography (US) in performing posterior sacroiliac ligament injection. METHODS: We examined SIJ and ligaments, and injected local anesthetics using ultrasonography. US guided needle insertions were performed. We also examined the cadevar of a 74-year-old woman to examine SIJ anatomy. RESULTS: US was performed in 61 male and 97 female outpatients (N = 158) with a mean age of 72.8 ± 10.9. US examination of the SIJ is difficult to perform because of its complex anatomy, and wide range of normal variations, and relative inaccessibility by surface scanning. The long posterior sacroiliac ligament (LPSL) is visualized as a hyper echoic laminated linear structure. We were able to confirm needle placement and area affected by local anesthetics. CONCLUSIONS: Our study suggests that US can be useful in performing posterior sacroiliac ligament injections. Sufficient anatomical knowledge and extensive US experience are essential in performing these injections.

Phase-field model for reconstructed stepped surface.

We formulate a phase-field, or diffuse-interface, model for the evolution of stepped surfaces under surface diffusion in the presence of distinct material parameters across nanoscale terraces. In the sharp-interface limit, our model reduces to a Burton-Cabrera-Frank (BCF)-type theory for the motion of noninteracting steps separating inhomogeneous terraces. This setting aims to capture features of reconstructed semiconductor, e.g., Si surfaces below the roughening transition. Our work forms an extension of the phase-field construction by Hu et al. [Physica D 241, 77 (2012)].

[Effect of the sacroiliac ligament block on intractable low back pain in elderly patients].

BACKGROUND: Lumbar spine disease in the elderly people is complicated by a variety of pathophysiology in the spine and the cause of the pain is unclear. Diagnosis of pain may be difficult in patients with pain in the thigh and groin area. Sacroiliac joint is supporting the trunk and movable joint. We examined the effect of the sacroiliac joint block for intractable low back pain. METHODS: Retrospectively we examined the duration of disease in patients with hip and leg pain visiting the hospital for eight months, and we questioned the site of pain awareness. Newton test, Gaenslen test, Patrick test and Fadire test were carried out for sacroiliac joint pain in patients with at least one positive finding. When performing sacroiliac ligaments block local anesthetics was injected to check the position of the dorsal sacroiliac ligaments under ultrasonic echo whenever possible. The block is performed with the patients prone at a point one finger from the posterior superior iliac spine level at an angle of 30-45 degrees downward toward the outside. Injecting the drugs penetrating the ligament continued to give a feel slightly outward to avoid the iliac Cattelan 23 G needle. We confirmed pain assessment NRS at 11 (0-10), and the improvement of pain was assessed with the change of the NRS on the next return. RESULTS: NRS showed a significant decrease at all points in time before block, their pain decreased gradually. The patients showed NRS improvement of more than 50% of the first block in 15 of 24 patients. CONCLUSIONS: Block at the posterior sacroiliac ligament region significantly reduced pain for chronic intractable low back pain. The block was shown to be effective as a treatment and for diagnosis.

[Case of pneumonitis caused by Yokukansan].

A 74-year-old man was admitted to our hospital complaining of severe neck pain and general fatigue. He had been undergoing treatment for post-operative neck pain at the out-patient clinic of our hospital, but was now complaining of pain more intense than usual. Chest X-rays revealed diffuse ground glass shadows in bilateral lung fields, and computed tomography revealed diffuse intestinal shadows. A drug lymphocyte stimulation test (DLST) was also performed at that time. Steroid pulse therapy improved the clinical symptoms, hypoxemia and chest X-ray findings. DLST performed again with Yokukansan and Hachimijiogan 133 days after the initial diagnosis of pneumonitis showed Yokukansan was positive. This result showed Yukukansan may be a causative drug for allergic drug-induced pneumonitis. Any drugs including kanpo may be possible to induce allergic pneumonitis.