Bimanual Recoupling by Visual Cueing in Callosal Disconnection

Abstract

The cerebral control of bimanual movements is not completely understood. We investigated a 59-year-old, right-handed man who presented with an acute bimanual coordination deficit. Magnetic resonance imaging showed a lesion involving the entire corpus callosum, which was found on stereotactic biopsy to be an ischemic infarct. Paired-pulse transcranial magnetic stimulation indicated that the patient had a lack of interhemispheric inhibition, while intracortical inhibition in motor cortex of either side was normal. Functional magnetic resonance imaging showed activation of the left SMA, the bilateral motor cortex and anterior cerebellum during spontaneous bimanual thumb-index oppositions, which were uncoupled as evident from simultaneous electromyographic recordings. In contrast, when the bimanual thumb-index oppositions were cued by a visual stimulus, the movements of both hands were tightly correlated. This synchronized activity was accompanied by additional activations bilateral in lateral occipital cortex, dorsal premotor cortex and cerebellum. The data suggest that the visually cued movements of both hands were recoupled by action of a bihemispheric motor network.     

Influence of resection extent on morbidity in surgery for squamous cell cancer at the pharyngoesophageal junction

Purpose

Squamous cell cancer (SCC) of the pharyngoesophageal junction area has a poor prognosis mainly due to late symptom manifestation and diagnosis. Treatment of choice is still pharyngolaryngoesophagectomy, substantially affecting quality of life. Limited surgical procedures have been adopted as well. The aim of this retrospective study was to evaluate whether the extent of resection influences postoperative safety and mortality.

Methods

From 1984 to 2006, 66 patients were operated at a single tertiary referral center. Nineteen patients (28.8 %) had SCC of the hypopharynx and 47 patients (71.2 %) had SCC of the cervical and cervicothoracic esophagus. Thirty-five patients (53.0 %) underwent cervical esophageal resection (CE) and 31 underwent total esophagectomy (TE). In 39 patients (59.1 %), the larynx was preserved. Thirteen patients (19.7 %) underwent multimodal treatment.

Results

Overall postoperative morbidity was 69.7 % and reoperation rate reached 28.8 %. TE (P?=?0.03) and larynx preservation (P?=?0.02) were followed by a higher rate of non-lung infections compared with CE and pharyngolaryngectomy, respectively. Pulmonary complications have been observed more frequently after larynx preservation (P?=?0.02). Hospital mortality was 9.1 %. Four patients died after TE (12.9 %) and two patients died after CE (5.7 %). In all of them, the larynx had been preserved (15.4 %). Overall, 53 patients (80.3 %) died until follow-up. One-year and 5-year survival in patients with the major tumor burden at the cervicothoracic site was 35.7 and 0 %.

Conclusions

CE can be recommended as long as R0 resection is warranted. The advantage of larynx preservation is gained by higher morbidity and mortality rates and may not be recommended as standard procedure. Surgery may not be appropriate for advanced SCC in the cervicothoracic region.     

Clinical predictors of the psychosocial long term outcome after brain injury

Abstract

The correlation of clinical with psychological and social data is an attempt to find predictors of the definite long term outcome after brain injury. 34 patients were reexamined 3 to 8 years after the accident using a number of psychological tests. Additionally, life quality was defined and evaluated. Only patients with an initial Glasgow Coma Scale-Score of 3–12, an intracranial traumatic lesion on computertomography and age 16–65 years at the time of accident were included in this study. Patients exhibited a uniform pattern of disturbances in psychosocial long term outcome. These disturbances were compared with initial clinical data: memory, attention and learning were significantly correlated with the duration of coma and the presence of additional extracerebraI injuries. From the initial computerized tomography, the findings 'compression of basal cisterns' and lintracerebral contusion' showed to be predictors of the cerebral function. Late social status and behavior, defined as quality of life, were clearly related with initial clinical findings. In conclusionl there are early clinical predictors of the long term social and psychological outcome after brain injury. [Neural Res 1997; 19: 305–310]     

Prediction of conversion from paroxysmal to permanent atrial fibrillation

BACKGROUND: Paroxysmal atrial fibrillation (PAF) transits to permanent atrial fibrillation (PEAF). The current study was to determine whether a P wave-triggered P wave signal averaged electrocardiogram (P-SAECG) and chemoreflexsensitivity (CHRS) are useful to predict a conversion to PEAF in patients with PAF. METHODS: The filtered P wave duration (FPD) and the root mean square voltage of the last 20 ms of the P wave (RMS 20) were measured by P-SAECG. The ratio between the difference of RR intervals in the ECG and venous pO2 before and after 5-minutes oxygen inhalation is measured (ms/mmHg) for the determination of CHRS. Results: A total of 180 patients with PAF were enrolled and followed for a mean of 22.5 months. PEAF occurred in 38 patients (21%) and these patients had a significantly larger left atrial size (43.2 +/- 4.9 vs. 41.0 +/- 5.4 mm, P = 0.021), a significantly longer FPD (158.8 +/- 18.2 vs. 136.7 +/- 16.6 ms, P < 0.0001), and a significantly lower CHRS (1.96 +/- 0.99 vs. 2.44 +/- 1.19 ms/mmHg, P = 0.024) than patients with PAF. Patients with PEAF tended to have a lower RMS 20 (2.38 +/- 0.65 vs. 2.75 +/- 1.18 microV, P = 0.067) than patients with PAF. The chi(2) test showed that the combination of FPD > or = 145 ms, RMS 20 < or = 3.0 microV, left atrial size > or = 41 mm, and CHRS < or = 2.0 ms/mmHg had the best predictive power for PEAF. Patients who fulfilled these criteria had a 12-fold increased risk for a conversion from PAF to PEAF. CONCLUSIONS: Our results show that a P-SAECG, an analysis of CHRS, and left atrial enlargement are clinical predictors of a progression from PAF to PEAF.     

Endovascular stent-graft placement in aortic dissection: a meta-analysis.

AIMS: This article summarizes all available published data with respect to clinical success, complications, and outcomes of endovascular stent-graft placement among patients with descending aortic dissection (AD). METHODS AND RESULTS: We performed a meta-analysis of all published series on retrograde endovascular stent-graft placement encompassing >or=3 patients with AD. Thirty-nine studies, involving a total of 609 patients, were included. Procedural success was reported in 98.2+/-0.5% of patients. Major complications were reported in 11.1+/-1.4%, with the most dreaded neurologic complications in 2.9+/-0.7% patients. Periprocedural stroke was encountered more frequently than paraplegia (1.9+/-0.6% vs. 0.8+/-0.4%). Overall complications were significantly higher in patients undergoing stent-graft placement for acute AD than in patients with chronic AD (21.7+/-2.8% vs. 9.1+/-2.3%, P=0.005). The overall 30-day mortality was 5.3+/-0.9%, and was three-fold higher in patients with acute AD when compared with chronic AD (9.8+/-2.2% vs. 3.2+/-1.4%, P=0.015). In addition, 2.8+/-0.7% of patients died over a mean follow-up period of 19.5+/-7.1 months. Kaplan-Meier analysis yielded overall survival rates of 90.6+/-1.6% at 6 months, 89.9+/-1.7% at 1 year, and 88.8+/-1.9% at 2 years, respectively. CONCLUSION: Endovascular stent-graft placement in type B-AD is technically feasible with success rates of >95% in selected cohort. Although minimally invasive, major complications occurred in 14-18% of patients depending upon the acuity of presentation, with very low incidence of paraplegia. Both, acute and mid-term mortality of this novel treatment strategy appear to favourably compare with surgical treatment but further studies are necessary to compare stent-graft placement with medical treatment in uncomplicated AD.     

Röntgendensitometrische Messung der myokardialen Perfusionsreserve bei symptomatischen Patienten ohne angiographisch detektierbare Koronarstenosen

BACKGROUND: Patients with typical angina pectoris but without coronary artery disease (CAD) are distinct in clinical aspects. In only few patients no abnormality is detected. Most present at least one or more cardiovascular risk factors and/or signs of myocardial ischemia. As previous studies have shown, the coronary flow reserve is reduced in most of these cases. Regional measurements of the coronary flow reserve, performed by different approaches, have shown a profound variation in different myocardial areas. It is not yet clear, whether this heterogeneity is physiological or due to a pathologic process. PATIENTS AND METHODS: The aim of this study was the regional measurement of the myocardial perfusion reserve in patients without epicardial coronary stenoses using X-ray densitometry. RESULTS: The myocardial perfusion reserve (MPR) for all patients in the coronary artery territories was 1.6 +/- 0.5 (LAD), 2.0 +/- 0.7 (RCx), and 2.2 +/- 0.6 (RCA). In hypertensive patients the MPR was significantly lower in all territories compared to normotensive patients (1.5 +/- 0.3 vs. 2.2 +/- 0.7 [LAD], 1.8 +/- 0.5 vs. 2.5 +/- 0.7 [RCx], 2.1 +/- 0.5 vs. 2.5 +/- 0.9 [RCA]). The rise time (AT) is inversely proportional to the perfusion. At rest it was significantly shorter in hypertensive patients compared to normotensive patients (5.0 +/- 1.0 s vs. 6.5 +/- 2.0 s [LAD], 4.8 +/- 1.1 s vs. 6.1 +/- 2.6 s [RCx], 5.9 +/- 1.4 s vs. 7.8 +/- 4.0 s [RCA]), while there was no difference at maximum papaverine-induced hyperemia. A statistical correlation between MPR and wall thickness was found only for the LAD area. The heterogeneity of perfusion under basal flow conditions was more pronounced in normotensive than in hypertensive patients, while under maximal hyperemia there was no detectable difference. There was no statistically significant correlation between the semiquantiative wash-in counts of myocardial scintigraphy and MPR. CONCLUSION: In this group of symptomatic patients MPR is lower than the lower limit of normal MPR, which is 3 in healthy individuals according to the literature. Patients with known arterial hypertension show a more severely impaired MPR which is especially pronounced in the LAD area and can be explained by a higher perfusion at rest. According to the authors' approach X-ray densitometry in the setting of coronary angiography is feasible and cost-effective to obtain information about the microvasculature.     

Tissue Doppler imaging (TDI) for on-line detection of regional early diastolic ventricular asynchrony in patients with coronary artery disease

Diastolic filling of the left ventricle is often impaired in patients with coronary artery disease (CAD) in the absence of systolic wall motion abnormalities or previous myocardial infarction. The current study was designed to assess the ability of tissue Doppler imaging (TDI) for on-line detection of regional diastolic wall motion abnormalities to identify CAD in patients with preserved systolic function. 20 normal subjects (age 51 ± 13years) and 17 CAD patients with normal systolic function and 70% luminal narrowing of the LAD (age 56 ± 11years) were included. Coronary anatomy was unknown to the echocardiographer. In the parasternal short axis and the apical 4-chamber-view, peak tissue velocities of the anterior/inferior and the midseptal/midlateral LV segments during rapid ejection (RE), isovolumic relaxation (IR), rapid filling (RF) and atrial contraction (AC) were analyzed by color-M-Mode-TDI. In the apical view, in 13 of 35 (37%) patients with adequate recordings, myocardial asynchrony was detected during IR: while the septum was moving inwards (red color-coding), the lateral wall was moving outwards (blue/green coding). In the remaining 22 patients (63%) a slow, synchronous outward motion of septum and lateral wall with homogeneous color-coding (blue/green) was seen. Unblinding of the coronary status revealed a critical LAD stenosis in all 13 patients (100%) with myocardial asynchrony. Analysis of midseptal peak velocities during IR revealed positive velocities (1.22 ± 1.64cm/s) in CAD patients and negative velocities (–1.39 ± 0.81cm/s) in normal subjects. Thus, TD1 allowed for the on-line detection of early diastolic asynchrony in 13 of 16 (82%) patients with critical LAD-narrowing. Due to the rapid assessment of regional wall motion abnormalities, TDI might help to identify CAD in patients with normal systolic function.