Prognostic Factors of Hemifacial Spasm after Microvascular Decompression

Objective

The factors that influence the prognosis of patients with hemifacial spasm (HFS) treated by microvascular decompression (MVD) have not been definitely established. We report a prospective study evaluating the prognostic factors in patients undergoing MVD for HFS.

Methods

From January 2004 to September 2006, the authors prospectively studied a series of 293 patients who underwent MVD for HFS. We prospectively analyzed a number of variables in order to evaluate the predictive value of independent variables for the prognosis of patients undergoing MVD. The patients were followed-up at regular intervals and divided into as cured and unsatisfactory groups based on symptom relief. Uni- and multivariate analyses were performed using logistic regression models.

Results

A total 273 of 293 (94.2%) patients achieved symptom relief within one year after the operation. Intraoperatively, the indentation of the root exit zone was observed in 259 (88.5%) patients. Uni- and multivariate analyses revealed that the symptoms at postoperative 3 months (p<0.001) and indentation of the root exit zone (p=0.036) were associated with good outcomes.

Conclusion

The intraoperative finding of root exit zone indentation will help physicians determine the prognosis in patients with HFS. To predict the prognosis of HFS, a regular follow-up period of at least 3 months following MVD should be required.     

Multi-Modality Treatment for Intracranial Arteriovenous Malformation Associated with Arterial Aneurysm

Objective

Intracranial arteriovenous malformation (AVM) associated with aneurysm has been infrequently encountered and the treatment for this malady is challenging. We report here on our clinical experience with AVMs associated with arterial aneurysms that were managed by multimodality treatments, including clipping of the aneurysm, microsurgery, Gamma-knife radiosurgery (GKS) and Guglielmi detachable coil (GDC) embolization.

Methods

We reviewed the treatment plans, radiological findings and clinical courses of 21 patients who were treated with GKS for AVM associated with aneurysm.

Results

Twenty-seven aneurysms in 21 patients with AVMs were enrolled in this study. Hemorrhage was the most frequent presenting symptom (17 patients : 80.9%). Bleeding was caused by an AVM nidus in 11 cases, aneurysm rupture in 5 and an undetermined origin in 1. Five patients were treated for associated aneurysm with clipping followed by GKS for the AVM and 11 patients were treated with GDC embolization combined with GKS for an AVM. Although 11 associated aneurysms remained untreated after GKS, none of them ruptured and 4 aneurysms regressed during the follow up period. Two aneurysms increased in size despite the disappearance of the AVM nidus after GKS and then these aneurysms were treated with GDC embolization.

Conclusion

If combined treatment using microsurgery, GKS and endovascular treatment can be adequately used for these patients, a better prognosis can be obtained. In particular, GKS and GDC embolization are considered to have significant roles to minimize neurologic injury.     

Radiosurgical Considerations in the Treatment of Large Cerebral Arteriovenous Malformations

Objective

In order to establish the role of Gamma Knife radiosurgery (GKS) in large intracranial arteriovenous malformations (AVMs), we analyzed clinical characteristics, radiological features, and radiosurgical outcomes.

Methods

Between March 1992 and March 2005, 28 of 33 patients with large AVMs (> 10 cm³ in nidus-volume) who were treated with GKS underwent single session radiosurgery (RS), and the other 5 patients underwent staged volumetric RS. Retrospectively collected data were available in 23 cases. We analyzed treatment outcomes in each subdivided groups and according to the AVM sizes. We compared the estimated volume, defined as primarily estimated nidus volume using MR images, with real target volume after excluding draining veins and feeding arteries embedded into the nidus.

Results

Regarding those patients who underwent single session RS, 44.4% (8/18) had complete obliteration; regarding staged volumetric RS, the obliteration rate was 40% (2/5). The complete obliteration rate was 60% (6/10) in the smaller nidus group (10-15 cm³ size), and 25% (2/8) in the larger nidus group (over 15 cm³ size). One case of cerebral edema and two cases (8.7%) of hemorrhage were seen during the latent period. The mean real target volume for 18 single sessions of RS was 17.1 cm³ (10.1-38.4 cm³), in contrast with the mean estimated volume of 20.9 cm³ (12.0-45.0 cm³).

Conclusion

The radiosurgical treatment outcomes of large AVMs are generally poor. However, we presume that the recent development in planning software and imaging devices aid more accurate measurement of the nidus volume, therefore improving the treatment outcome.     

The role of routine spinal imaging and immobilisation in asymptomatic patients after gunshot wounds

Background

The role of routine dedicated spinal imaging and immobilisation following gunshot wounds (GSW) to the head, neck or torso has been debated. The purpose of this study was to determine the incidence of spinal column injury requiring stabilisation in evaluable patients following gunshot injury.

Methods

A retrospective study from of a Level I trauma centre from January 1995 to December 2004. All patients with GSW to the head, neck or torso and bony spinal column injury underwent medical record review to determine injury type, presentation, presence of concomitant spinal cord injury, treatment and outcome.

Results

A total of 4204 patients sustaining GSW to the head, neck or torso were identified. Complete medical records were available for the 327 (7.8%) patients with bony spinal column injury. Among these patients, 173 (52.9%) sustained spinal cord injury. Two patients (0.6%) with GSW to the torso and bony spinal column injury required operative spinal intervention. The indication for operative intervention in both cases was removal of a foreign body or bony fragment for decompression of the spinal canal. None of the 4204 patients sustaining GSW to the head, neck or torso demonstrated spinal instability requiring operative intervention, and only 2/327 (0.6%) required any form of operative intervention for decompression.

Conclusion

Spinal instability following GSW with spine injury is very rare. Routine spinal imaging and immobilisation is unwarranted in examinable patients without symptoms consistent with spinal injury following GSW to the head, neck or torso.     

A 6-year review of total parenteral nutrition use and association with late-onset acute respiratory distress syndrome among ventilated trauma victims

Aim

To establish whether total parenteral nutrition (TPN) for ventilated trauma victims is associated with late-onset acute respiratory distress syndrome (ARDS) independent of ventilation and transfusion parameters.

Method

Intensive care unit data over 6 years from a level I centre regarding all trauma victims ≥16 years old who underwent mechanical ventilation within the first 48 h of admission were examined. Patients were prospectively followed for late ARDS. Variables were examined for significant changes over time and independent associations with late ARDS were determined.

Results

Of 2346 eligible patients among whom 404 (17.2%) were exposed to TPN, 192 (8.2%) met criteria for late ARDS. The incidence of late ARDS among those exposed to TPN was 28.7% (116/404) compared with 3.9% (76/1942) among those not so exposed. Adjustments for potential confounding associated risk factors were made.

Conclusions

TPN administration is independently associated with late ARDS, and its use among critically ill trauma victims should be carefully scrutinised.     

Mortality Impact of Hypothermia After Cavitary Explorations in Trauma

Background  Admission hypothermia (core temperature ≤ 35°C) is an independent risk factor for mortality after trauma. The predictive value of perioperative core temperatures during acute trauma surgery, however, although widely employed as a criterion for initiating damage control, is unknown. We hypothesized that for trauma patients undergoing laparotomy or thoracotomy, early postoperative hypothermia is a predictor of mortality. Methods  After institutional review board (IRB) approval, all critically ill trauma patients undergoing cavitary surgery (laparotomy or thoracotomy) at a level 1 trauma center from 01/1998 to 07/2006 were identified from the trauma registry. Immediate postoperative core temperature (Tc) was used to classify patients as hypothermic (Tc ≤ 35°C) or normothermic (Tc > 35°C). The profoundly hypothermic subgroup of patients with a Tc < 33°C was also analyzed. Results  During the study period, 2,489 patients required cavitary surgery, 1,252 of whom (50%) were admitted to the intensive care unit (ICU). On arrival in the ICU 15% of the patients had a Tc ≤ 35°C and were more likely to be ≥ 55 years old (12% versus 7%; p = 0.04); in addition, they were hypotensive on admission (25% versus 13%; p < 0.001), had a lower admission Glasgow Coma Score (GCS; 11 ± 5 versus 14 ± 3; p < 0.001), a higher Injury Severity Score (ISS; 29 ± 15 versus 22 ± 12; p < 0.001), higher head and chest Abbreviated Injury Scale (AIS), and greater intraoperative blood loss (2.6 ± 2.4 l versus 1.7 ± 1.8 l; p < 0.001). When compared to patients who were normothermic at the end of their operation, hypothermic patients had a significantly higher mortality (35% versus 8%; p < 0.001). With decreasing Tc, there was a stepwise increase in mortality. Compared to patients with a Tc > 35°C, the relative risk of death for patients with a Tc between 35°C and 33°C was 4.0, and that for patients with a Tc ≤ 33°C it was 7.1. After adjusting for multiple differences between groups, postoperative hypothermia remained an independent predictor of mortality (adjusted odds ratio [OR] 3.2; 95% confidence interval [CI] 1.9–5.3; p < 0.001). Conclusions  Postoperative hypothermia is common in critically injured patients requiring cavitary surgery and is an independent predictor of mortality. The impact of measures to maintain or restore normothermia in the operating room warrants further investigation. This work was presented at the 2008 Annual Scientific Meeting of the Trauma Association of Canada (TAC), April 3–5, 2008, Whistler, British Columbia, Canada.     

Markers of coronary sinus accessory pathways in pediatrics

Introduction: Coronary sinus accessory pathways (CSAPs), atrioventricular connections formed by the coronary sinus myocardial coat, have been described in adult patients, but not systematically described in pediatric patients.
Methods: Patients who underwent CSAP ablation were compared to patients with right posteroseptal (RPS) pathway ablation (control group) from November 2004 to June 2007. Retrospective reviews of preablation 12-lead electrocardiogram (EKG), fluoroscopic, and intracardiac electrogram data were then performed to identify electrophysiologic markers of CSAP.
Results: A total of 23 patients were identified: 13 with CSAP and 10 with RPS pathways. Preablation EKGs demonstrated preexcitation in 8/10 (80%) patients with RPS pathways versus 9/13 (69%) patients with CSAP (P = 0.66). Preexcitation with a negative delta wave in lead II was seen in 5/9 (56%) patients with CSAP versus 0/8 in RPS (P = 0.029), and preexcitation with a positive delta wave in augmented vector right (aVR) was seen in 9/9 (100%) patients with CSAP versus 3/8 (37.5%) with RPS (P = 0.009). Accessory pathway (AP) potentials were seen on the coronary sinus (CS) catheter in 6/13 (46%) of CSAP and in 0 RPS ablations (P = 0.019). Recurrence of tachycardia occurred in 5/13 (38%) of patients with CSAP and 1/10 (10%) of patients with RPS pathways (P = 0.18).
Conclusions: CSAPs should be considered when preablation EKG demonstrates preexcitation with a negative delta wave in lead II and a positive delta wave in aVR, and if an AP potential is seen on the CS catheter. Recurrence of tachycardia postablation or the need for multiple ablations should raise suspicion for a CSAP.     

Design of mutant beta2 subunits as decoy molecules to reduce the expression of functional Ca2+ channels in cardiac cells

Calcium influx through long-lasting ("L-type") Ca(2+) channels (Ca(V)) drives excitation-contraction in the normal heart. Dysregulation of this process contributes to Ca(2+) overload, and interventions that reduce expression of the pore-forming alpha(1) subunit may alleviate cytosolic Ca(2+) excess. As a molecular approach to disrupt the assembly of Ca(V)1.2 (alpha(1C)) channels at the cell membrane, we targeted the Ca(2+) channel beta(2) subunit, an intracellular chaperone that interacts with alpha(1C) via its beta interaction domain (BID) to promote Ca(V)1.2 channel expression. Recombinant adenovirus expressing either the full beta(2) subunit (Full-beta(2)) or truncated beta(2) subunit constructs lacking either the C terminus, N terminus, or both (N-BID, C-BID, and BID, respectively) fused to green fluorescent protein were developed as potential decoys and overexpressed in HL-1 cells. Fluorescence microscopy revealed that the localization of Full-beta(2) at the surface membrane was associated with increased Ca(2+) current mainly attributed to Ca(V)1.2 channels. In contrast, truncated N-BID and C-BID constructs showed punctate intracellular expression, and BID showed a diffuse cytosolic distribution. Total expression of the alpha(1C) protein of Ca(V)1.2 channels was similar between groups, but HL-1 cells overexpressing C-BID and BID exhibited reduced Ca(2+) current. C-BID and BID also attenuated Ca(2+) current associated with another L-type Ca(2+) channel, Ca(V)1.3, but they did not reduce transient Ca(2+) currents attributed to Ca(V)3 channels. These results suggest that beta(2) subunit mutants lacking the N terminus may preferentially disrupt the proper localization of L-type Ca(2+) channels in the cell membrane. Cardiac-specific delivery of these decoy molecules in vivo may represent a gene-based treatment for pathologies involving Ca(2+) overload.     

Plasma free fatty acid level patterns according to cardiovascular risk status in postmenopausal women

BACKGROUND: The present study examines changes in the pattern of plasma free polyunsaturated fatty acids (PUFA) according to menopausal status and the existence of diabetes mellitus (DM) or coronary heart disease (CHD) in Korean women. METHODS: The participants were as follows; premenopausal women (PRE, n=20) and postmenopausal women without any known chronic disease (POST, n=35), with DM (DM, n=35), or with angiographically proven CHD (CHD, n=30). Plasma free fatty acids were measured in all participants. RESULTS: Healthy premenopausal women had a higher ratio of omega-3/omega-6 PUFA than postmenopausal women (p=0.001). As expected, the PRE group had higher docsapentaenoic acid (DPA) and docosahexaenoic acid (DHA) levels (p<0.05) and lower arachidonic acid levels (p<0.05) than the POST group. In turn, the healthy POST group had higher levels of DPA and DHA compared to the DM or CHD groups (p<0.05). There were significant shifts of increased omega-6 and decreased omega-3 among the women, according to each disease. CONCLUSIONS: There was a significant relationship between omega-3 and omega-6 PUFA profiles and risk for CHD in women. This metabolic profile of PUFA might be an important surrogate marker in postmenopausal women.