Cerebral blood flow autoregulation in ischemic heart failure.

Patients with ischemic heart failure (iHF) have a high risk of neurological complications such as cognitive impairment and stroke. We hypothesized that iHF patients have a higher incidence of impaired dynamic cerebral autoregulation (dCA). Adult patients with iHF and healthy volunteers were included. Cerebral blood flow velocity (CBFV, transcranial Doppler, middle cerebral artery), end-tidal CO2 (capnography), and arterial blood pressure (Finometer) were continuously recorded supine for 5 min at rest. Autoregulation index (ARI) was estimated from the CBFV step response derived by transfer function analysis using standard template curves. Fifty-two iHF patients and 54 age-, gender-, and BP-matched healthy volunteers were studied. Echocardiogram ejection fraction was 40 (20-45) % in iHF group. iHF patients compared with control subjects had reduced end-tidal CO2 (34.1 ± 3.7 vs. 38.3 ± 4.0 mmHg, P < 0.001) and lower ARI values (5.1 ± 1.6 vs. 5.9 ± 1.0, P = 0.012). ARI <4, suggestive of impaired CA, was more common in iHF patients (28.8 vs. 7.4%, P = 0.004). These results confirm that iHF patients are more likely to have impaired dCA compared with age-matched controls. The relationship between impaired dCA and neurological complications in iHF patients deserves further investigation.

Restless legs syndrome in Wilson's disease: frequency, characteristics, and mimics.

OBJECTIVE: To determine characteristics, clinical significance, frequency, and mimics of restless legs syndrome (RLS) in a cohort of Wilson's disease (WD, n = 42/f = 18), compared to healthy, matched controls. MATERIALS AND METHODS: Structured clinical interviews (patients and caregiving family members), repeated neurological examinations (afternoon and presleep), comprehensive laboratory tests, WD-, RLS-, and sleep-specific rating scales, and video-polysomnography. RESULTS: Thirteen patients with WD (13/42 = 31.0%) clearly fulfilled the five diagnostic criteria of RLS; in eight patients (19.1%), the burden of RLS was clinically significant. The RLS was of moderate severity, equally distributed among sexes, manifested mainly in the evening and before falling asleep, and had developed mostly after clinical manifestation of WD (time elapsed 10.2 ± 14.5 years), still at a young mean age (27.5 ± 11.5 years). The known RLS-associated features were absent (normal iron and kidney parameters) or rare (positive family history, polyneuropathy). Compared to WD patients without RLS, patients with RLS were significantly elder and had suffered longer from WD. WD-specific RLS mimics as well as RLS confounding motor comorbidities (dystonia, tremor, chorea) were frequent and a diagnostic challenge; in difficult cases, the differentiation was reached by clinical observation of the motor behavior in the evening or at nighttime. CONCLUSION: RLS was frequent in this cohort of WD and might be causally related to WD. RLS should be included in the diagnostic work-up of WD. In complex motor disorders, differential diagnosis of RLS might require evening/nighttime examination and video-polysomnography. In WD patients with a clinically significant RLS, treatment with dopaminergic substances may be considered.

Cerebral Hemodynamic Effects of Cheyne-Stokes Respiration in a Patient with Stroke.

INTRODUCTION: Cheyne-Stokes respiration (CSR) and central sleep apnea (CSA) are common in patients with heart failure and/or stroke. We aim to describe the cerebrovascular effects of CSR during the acute phase of stroke in a heart failure patient. CASE REPORT: A 74-year-old male with previous dilated cardiomyopathy had sudden onset of right hemiparesis and aphasia. A transcranial Doppler was performed with continuous measurement of blood pressure (BP) (Finometer) and end-tidal CO2 (nasal capnography). Offline analysis of hemodynamic data disclosed relatively large periodic oscillations of both cerebral blood flow velocity and BP related to the CSR breathing pattern. Derivate variables from the cerebrovascular resistance were calculated (critical closing pressure and resistance-area product), demonstrating that there may be a myogenic impairment of cerebral blood flow (CBF) control in the affected hemisphere of this subgroup of patient. CONCLUSION: There is an impairment of CBF regulation in the affected hemisphere of the patient with ischemic stroke and CSR, highlighting the role of cerebral hemodynamic monitoring in this scenario.

Glossopharyngeal neuralgia: neurosurgical treatment and differential diagnosis.

The objective of this study was to review the literature on glossopharyngeal neuralgia (GN) and to discuss its differential diagnosis and treatment options. Despite the significant improvement of trigeminal neuralgia with pharmacological treatment, GN has a higher incidence of treatment failure and neurosurgery is necessary for the majority of patients. Functional neurosurgery has a great rate of success for GN, especially techniques such as percutaneous thermal rhizotomy, trigeminal tractotomy and/or nucleotomy. The main problem with GN remains the diagnosis as it is a rare disease with similarities to trigeminal neuralgia, including the same pharmacological treatment. Facial pain specialists should be trained to achieve a better accuracy of diagnosis.

Cerebral hemodynamics with intra-aortic balloon pump: business as usual?

OBJECTIVE: Intra-aortic balloon pump (IABP) is commonly used as mechanical support after cardiac surgery or cardiac shock. Although its benefits for cardiac function have been well documented, its effects on cerebral circulation are still controversial. We hypothesized that transfer function analysis (TFA) and continuous estimates of dynamic cerebral autoregulation (CA) provide consistent results in the assessment of cerebral autoregulation in patients with IABP. APPROACH: Continuous recordings of blood pressure (BP, intra-arterial line), end-tidal CO2, heart rate and cerebral blood flow velocity (CBFV, transcranial Doppler) were obtained (i) 5 min with IABP ratio 1:3, (ii) 5 min, starting 1 min with the IABP-ON, and continuing for another 4 min without pump assistance (IABP-OFF). Autoregulation index (ARI) was estimated from the CBFV response to a step change in BP derived by TFA and as a function of time using an autoregressive moving-average model during removal of the device (ARI t ). Critical closing pressure and resistance area-product were also obtained. MAIN RESULTS: ARI with IABP-ON (4.3 ± 1.2) were not different from corresponding values at IABP-OFF (4.7 ± 1.4, p = 0.42). Removal of the balloon had no effect on ARI t , CBFV, BP, cerebral critical closing pressure or resistance area-product. SIGNIFICANCE: IABP does not disturb cerebral hemodynamics. TFA and continuous estimates of dynamic CA can be used to assess cerebral hemodynamics in patients with IABP. These findings have important implications for the design of studies of critically ill patients requiring the use of different invasive support devices.

The carotid artery as an alternative site for dynamic autoregulation measurement: an inter-observer reproducibility study.

The internal carotid artery (ICA) has been proposed as an alternative site to the middle cerebral artery (MCA) to measure dynamic cerebral autoregulation (dCA) using transcranial Doppler ultrasound (TCD). Our aim was to test the inter-operator reproducibility of dCA assessment in the ICA and the effect of interaction amongst different variables (artery source × operator × intra-subject variability). Two operators measured blood flow velocity using TCD at the ICA and MCA simultaneously on each side in 12 healthy volunteers. The autoregulation index (ARI) was estimated by transfer function analysis. A two-way repeated measurements ANOVA with post-hoc Tukey tested the difference between ARI by different operators and interaction effects were analysed based on the generalized linear model. In this healthy population, no significant differences between operator and no interaction effects were identified amongst the different variables. This study reinforced the validity of using the ICA as an alternative site for the assessment of dCA. Further work is needed to confirm and extend our findings, particularly to disease populations.

Contractions of the gastric antrum induced by stimulation of the medial forebrain bundle in the rat.

Glucoreceptors sensitive to cytoglucopenia exist in the medial forebrain bundle of the rat. The selective activation of these receptors provokes an increase in glycemia and gastric secretion. In the present work, we found that stimulation of this diencephalic area in rats also provokes potent gastric contractions. Stimulation with high voltages usually inhibited this effect.

Myenteric neurons of the mouse small intestine. Morphometry and acetylcholinesterase activity.

1. The myenteric plexus of the small intestine of five C57BL/6J male 5-month-old mice was investigated in whole-mount preparations of the muscularis externa by Giemsa staining and by the acetylcholinesterase (AChE) histochemical technique. 2. The neuronal density was 20212 +/- 3038/cm2 (mean +/- SEM) in the duodenum, 21948 +/- 1488/cm2 in the jejunum, and 25048 +/- 2356/cm2 in the ileum. The difference in neuronal density between duodenum and ileum was statistically significant (P < 0.05). The total serosal surface area of the small intestine was about 30.80 +/- 2.90 cm2, and the total number of neurons was estimated at about 690,000. 3. The neuronal cell and nucleus profile areas ranged, respectively, from 23 to 325 microns 2 and from 6 to 95 microns 2 in the small intestine of the mice studied. There were no significant differences in any of the 3 regions in terms of average neuronal cell or nucleus profile areas. 4. For the histochemical demonstration of AChE, the "direct coloring" copper ferrocyanide method was used. AChE-positive nerve fibers were distributed in the myenteric plexus which was formed by a primary meshwork of relatively large nerve bundles and a secondary meshwork of finer nerve bundles. Most of the neurons of the plexus displayed AChE activity in the cytoplasm though the neurons presented different reaction intensities.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical management of Guyon's canal syndrome, an ulnar nerve entrapment at the wrist: report of two cases.

Guyon's canal syndrome, an ulnar nerve entrapment at the wrist, is a well-recognized entity. The most common causes that involve the ulnar nerve at the wrist are compression from a ganglion, occupational traumatic neuritis, a musculotendinous arch and disease of the ulnar artery. We describe two cases of Guyon's canal syndrome and discuss the anatomy, aetiology, clinical features, anatomical classification, diagnostic criteria and treatment. It is emphasized that the knowledge of both the surgical technique and anatomy is very important for a satisfactory surgical result.

[Idiopathic spinal epidural hematoma in patients with sudden paraplegia: a case report]. / Hematoma epidural espinal idiopático en pacientes con paraplejía súbita: a propósito de un caso.

INTRODUCTION: Spontaneous spinal epidural hematoma (SEH) represents 0.3-0.9% of spinal epidural space-occupying lesions, and most surgeons advocate aggressive and early surgical intervention. In this paper we describe a patient with SEH with sudden paraplegia. CASE REPORT: This 30-year-old man had experienced one prior episode of sudden dorsal pain two days before the current admission and while he waited medical attendance, his legs suddenly became weak, and immediately afterwards, he became completely paraplegic in minutes. The patient had complete paraplegia, analgesia below the T4 level and urinary retention. He had no anticoagulant agent and no coagulopathic disease. He was submitted to computerized tomography that demonstrated a dorsally located epidural hematoma extending from the T3 to the T6 level with spinal cord compression. A laminectomy from T3 to T7 was performed four hours after the onset of the symptom. In postoperative time the patient presented the partial sensorial recovery and motor force grade II. The patient was directed to a neurorehabilitation program and in the last medical evaluation he presented recovery for motor grade III-IV, without pain. CONCLUSION: The SHE is rare, with severe neurological consequences for patients and early surgical treatment persist as essential for motor recovery.

Actual asymptomatic epidural hematomas in childhood. Report of three cases.

It is well known that the mortality of epidural hematoma (EDH) cases is directly related to the patient's level of consciousness at the time of surgery. The authors report three actually asymptomatic patients with mild head injury, in whom the diagnosis of EDH was possible because of quite broad indications for computed tomographic (CT) scanning, which allowed diagnosis and treatment in an early phase. These cases illustrate the possibility of an EDH in a totally asymptomatic patient.

Traumatic acute giant epidural hematoma in a hydrocephalic shunted child.

Extradural hematoma (EDH) is considered to be a rare complication of head trauma in children, and represents a serious and urgent pathology from which complete recovery can be expected if specialized treatment is instituted in time. In this article, the authors report the potential danger to a hydrocephalic shunted child who was apparently asymptomatic at the time of hospital admission with a mild head injury and developed an EDH of venous origin. This child had a rapid (time interval from injury to decerebrate posture of about 2 h), atypical (remained asymptomatic most of the time until abruptly deterioration) and fatal course, stressing the importance of early diagnosis and rapid therapy in order to avoid the death of the patient. The authors discuss the role of the ventriculoperitoneal shunting system in the lack of clinical symptoms associated with the presence of a giant EDH and a rapid and fatal course, and stress the importance of computed tomographic (CT) scanning in these patients, even if they are asymptomatic. If a skull fracture is suspected, a CT scan must be performed without delay.

Myenteric neurons of the mouse small intestine. Morphometry and acetylcholinesterase activity

1. The myenteric plexus of the small intestine of five C57BL/6J male 5-month-old mice was investigated in whole-mount preparations of the muscularis externa by Giemsa staining and by the acetylcholinesterase (AChE) histochemical technique. 2. The neuronal density was 20212 ñ 3038/cm² (mean ñ SEM) in the duodenum, 21948 ñ 1488/cm² in the jejunum, 25048 ñ 2356/cm² in the ilium. The difference in neuronal density between duodenum and ileum was statistically significant (P<0,05). The total serosal surface area of the small intestine was about 30.80 ñ 2.90 cm², and the total number of neurons was estimated at about 690,000. 3. The neuronal cell and nucleus profile areas ranged, respectively, from 23 to 325 µm² and from 6 to 95 µm² in the small intestine of the mice studied. There were no significant differences in any of the 3 regions in terms of average neuronal cell or nucleus profile areas. 4. For the histochemical demonstration of AChE, the "direct coloring" copper ferrocyanide method was used. AChE-positive nerve fibers were distributed in the myenteric plexus which was formed by a primary meshwork of relatively large nerve bundles and a secondary meshwork of finer nerve bundles. Most of the neurons of the plexus displayed AChE activity in the cytoplasm though the neurons presented different reaction intensities. 5. The results of the present study show that the myenteric plexus of the C57BL/6J mouse small intestine contains a large number of neurons which have different sizes and AChE activities