Sacral Stress Fracture following the Bone Union of Lumbar Spondylolysis.

While 22 articles have reported on sacral stress fractures, it is a rare injury and its etiology is not well known. We present the case of a 16-year-old male who presented with low back pain in 2015. He was a high school soccer player with a previous history of a bilateral L5 lumbar spondylolysis in 2014. The patient refrained from soccer and wore a brace for six months. Two months after restarting soccer, he again complained of low back pain. After 1 year, a lumbar spine computed tomography revealed the bone union of the spondylolysis. At his first visit to our hospital, his general and neurological conditions were normal and laboratory data were within the normal range. Sacral coronal magnetic resonance imaging (MRI) of the left sacral ala revealed an oblique lineal signal void surrounding bone marrow edema. Based on his symptoms, sports history, and MRI, he was diagnosed with a sacral stress fracture. He again refrained from soccer; his low back pain soon improved, and, after 1 year, the abnormal signal change had disappeared on sacral MRI. Recurrent low back pain case caused by a sacral stress fracture occurring after the bone union of lumbar spondylolysis is uncommon.

Automated analysis of fluvoxamine in rat plasma using a column-switching system and ion-pair high-performance liquid chromatography.

We have established a robust, fully automated analytical method for the analysis of fluvoxamine in rat plasma using a column-switching ion-pair high-performance chromatography system. The plasma sample was injected onto a precolumn packed with Shim-pack MAYI-ODS (50 microm), where the drug was automatically purified and enriched by on-line solid-phase extraction. After elution of the plasma proteins, the analyte was back-flushed from the precolumn and then separated isocratically on a reversed-phase C18 column (L-column ODS) with a mobile phase (acetonitrile-0.1% phosphoric acid, 36:64, v/v) containing 2 mM sodium 1-octanesulfonate. The analyte was monitored by a UV detector at a wavelength of 254 nm. The calibration line for fluvoxamine showed good linearity in the range of 5-5000 ng/mL (r > 0.999) with the limit of quantification of 5 ng/mL (RSD = 6.51%). Accuracy ranged from -2.94 to 4.82%, and the within- and between-day precision of the assay was better than 8% across the calibration range. The analytical sensitivity and accuracy of this assay is suitable for characterization of the pharmacokinetics of orally-administered fluvoxamine in rats.

Cognitive impairment associated with intraoperative and postoperative hypoperfusion without neurologic deficits in a patient undergoing carotid endarterectomy.

BACKGROUND: Neuropsychological testing detects cognitive impairment in 20% to 30% of patients after carotid endarterectomy (CEA). CASE DESCRIPTION: A 51-year-old man with asymptomatic right cervical internal carotid artery (ICA) stenosis underwent a CEA. Intraoperative transcranial regional cerebral oxygen saturation monitoring revealed ischemia in the right cerebral hemisphere during ICA clamping and transient hyperemia subsequent to ICA declamping. The patient recovered without the appearance of new neurologic deficits. Brain single-photon emission computed tomography performed immediately after CEA showed a decrease in cerebral blood flow in the right cerebral hemisphere. Diffusion-weighted magnetic resonance imaging showed no new abnormal findings. Positron emission tomography performed 2 months after surgery revealed decreased cerebral metabolic rate of oxygen in the right cerebral hemisphere, and neuropsychological testing demonstrated a decline in performance IQ relative to preoperative levels. CONCLUSIONS: Intraoperative ischemia and postischemic delayed hypoperfusion in CEA can impair cognition even in the absence of development of postoperative neurologic deficit.

Stevens-Johnson syndrome associated with intravenous acetazolamide administration for evaluation of cerebrovascular reactivity. Case report.

A 62-year-old man with left middle cerebral artery stenosis manifesting as transient ischemic attack underwent evaluation of regional cerebrovascular reactivity to acetazolamide using single photon emission computed tomography. Three days after intravenous administration of acetazolamide, erythematous eruptions of various sizes appeared on his back and spread over almost his entire body. Subsequently, painful ulcerations developed on his lips, and oral and nasal mucosa, and the conjunctiva became hyperemic, indicating Stevens-Johnson syndrome. The results of the lymphocyte transformation test were positive to only acetazolamide. Stevens-Johnson syndrome, also known as erythema multiforme major, can be life-threatening, and may be induced by intravenous administration of acetazolamide.

Cerebral hyperperfusion after carotid endarterectomy is associated with preoperative hemodynamic impairment and intraoperative cerebral ischemia.

The aim of this study was to investigate whether postoperative hyperperfusion is associated with preoperative cerebral hemodynamic impairment due to chronic ischemia and with acute cerebral ischemia during clamping of the internal carotid artery (ICA) during carotid endarterectomy (CEA). Transcranial cerebral oxygen saturation (SO2) was monitored intraoperatively using near-infrared spectroscopy in 89 patients undergoing CEA for ipsilateral ICA stenosis (>70%). Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide were also measured using single photon emission computed tomography (SPECT) before CEA. In addition, CBF was measured immediately after CEA and on the third postoperative day. Hyperperfusion (CBF increase>100% compared with preoperative values) was observed immediately after CEA in 10 of 18 patients (56%) with reduced preoperative CVR. Also, post-CEA hyperperfusion was observed in nine of 16 patients (56%) whose SO2 during clamping of the ICA decreased to less than 90% of the preclamping value. Logistic regression analysis showed that reduced preoperative CVR and reduced SO2 during ICA clamping were significant independent predictors of the development of hyperperfusion immediately after CEA. In fact, all patients with reduced preoperative CVR and reduced SO2 during ICA clamping developed post-CEA hyperperfusion, and two of these patients developed cerebral hyperperfusion syndrome. These data suggest that development of cerebral hyperperfusion after CEA is associated with preoperative hemodynamic impairment and intraoperative cerebral ischemia.

Evaluation of twitch responses obtained from abductor hallucis muscle as a monitor of neuromuscular blockade: Comparison with the results from adductor pollicis muscle.

The twitch responses evoked from the abductor hallucis muscle (AHM) and the adductor pollicis muscle (APM) were examined simultaneously in 20 anesthetized patients following a single bolus intravenous administration of 0.04 mg·kg-1 of vecuronium bromide. The mean onset time of vecuronium-induced depression of AHM twitch responses was significantly slower than that of APM twitch responses (4.9±1.5 minvs 3.7±1.2 min, mean±SD,P<0.001), and when the clinical duration times of vecuronium were compared, AHM twitch responses recovered more quickly than APM twitch responses (15.3±4.1 minvs 19.6±6.7 min,P<0.01), although there was no statistically significant difference in the spontaneous recovery time between AHM and APM (9.8±2.9 minvs 10.0±3.6 min). It is concluded that the twitch responses of AHM may be a useful monitor of neuromuscular blockade in anesthetized patients in whom setting the blockade monitor on the patient's arms is difficult, although monitoring of twitch response of AHM is less sensitive than that of APM in case of vecuronium administration.

Cryocautery of sensitized skin areas for the relief of pain due to post-herpetic neuralgia.

Fourteen patients whose post-herpetic neuralgia could not be alleviated by conventional methods were treated with cryocautery using a stick of solid carbon dioxide (dry ice) applied directly to the hyperesthetic skin areas of the cutaneous scars. Follow-up evaluation revealed that 5 of 14 subjects maintained excellent pain relief and another 5 subjects showed good relief. Ten subjects discontinued further therapeutic procedures after cryocautery even though some low grade pain persisted. We believe that cryocautery of localized skin areas is a valuable method for treating patients with post-herpetic neuralgia who have not been improved by conventional methods. Disadvantages of this procedure are discussed.