Can cerebral vasoreactivity predict cerebral tolerance to carotid clamping during carotid endarterectomy?

Cerebral vasoreactivity (CVR) was evaluated as a preoperative test in predicting cerebral tolerance to carotid clamping.A consecutive series of 115 carotid endarterectomy (CEA) cases were studied. Before surgical operation CVR was evaluated, by measuring the mean velocity of the middle cerebral artery (mv-MCA) using transcranial Doppler (TCD) at the basal condition and 20 min after intravenous administration of acetazolamide (1 g). CEA was performed under general anesthesia. TCD was used during surgery to evaluate mv-MCA and to calculate mv-MCA clamping/mv-MCA pre-clamping x100 ratio (mv-MCA%), which was used as the parameter to validate CVR.CVR did not correlate with mv-MCA% (r=0.22). There was no significant difference (P=0.09) between mean values of the non shunted subgroup and the shunted one.CVR does not seem to be suitable for evaluating cerebral tolerance to carotid clamping.     

What does cerebral oximetry measure?

Editor—We feel that the recent paper by Yoshitani andcolleagues¹ raises important issues. They demonstrated that,in patients undergoing elective hip arthroplasty, normovolaemichaemodilution caused no change in jugular bulb saturations () but decreased cerebral saturations () when measured with a cerebral oximeter (INVOS 4100S). Two explanationswere offered for the unexpected disparity in readings. First,they postulated that subtle changes     

Is unilateral antegrade cerebral perfusion equivalent to bilateral cerebral perfusion for patients undergoing aortic arch surgery?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether unilateral antegrade cerebral perfusion is equivalent to bilateral cerebral plegia for cerebral protection during aortic arch surgery. Altogether 233 papers were found using the reported search, of which 17 presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these papers are tabulated. These papers documented antegrade selective cerebral perfusion in a total of 3548 patients: bilateral cerebral perfusion in 2949 patients and unilateral perfusion in 599 patients. Both methods of cerebral perfusion resulted in neurological injury rates of <5%, but the period of antegrade cerebral perfusion allowed by bilateral perfusion was significantly higher. While unilateral perfusion allowed around 30-50 min, bilateral perfusion allowed 86 to over 164 min of ASCP with an acceptably low CVA rate. Therefore, we conclude that while both methods are acceptable, once the ASCP time is expected to rise over 40-50 min, bilateral cerebral perfusion is the technique that is best documented to be safe.     

Are there still unclassified cerebral tumours?

Summary The case of a stillborn full-term child is presented, which showed a fistsized supratentorial tumour. The origin of the anaplastic tumour from the ependymal surface is discussed. However, the mass remains an Unclassified Tumour.     

Aspiration or extirpation in cerebral abscess surgery?

The author carried out CT investigation of 11 patients who recovered after cerebral abscess operation. The finding established in all cases was a hypodensic area of various extensions, which, in 4 patients, made the impression of pseudocysts. Large pathologic lesions were found mainly in the patients in whom healing was complicated by relapse. Surprisingly, rather extensive pathologic changes in the patients were found which were cured by so-called minimalized surgical intervention. The author imputes these changes to the remaining granulation tissue of the abscess capsula, which worsens conditions for healing. Aspiration is suitable mainly in cases in which the abscess is not — or only slightly encapsulated. Preoperation CT scans cannot establish exactly the presence and eventual thickness of the capsula. The establishment relationship of the kind and extent of operation to the extent of later cerebral tissue changes in CT findings requires further observation and verification in a larger group of patients.     

Synovial sarcoma—unusual presentation with cerebral hemorrhage

Introduction Soft-tissue sarcomas account for 1% of all malignancies in adults. Typical symptoms comprise a growing and painless mass. Occasionally, the diagnosis is facilitated by secondaries.Materials and methods Here we report the first case presented with intracranial hemorrhage caused by a metastasis of a previously unknown synovial sarcoma. The 74-year-old female patient was under anticoagulation for recurrent thrombosis of the right popliteal vein due to compression by the sarcoma, misdiagnosed as Baker`s cyst. The brain metastasis was resected, and after an incisional biopsy of the suspected tumor, which confirmed the diagnosis of a synovial sarcoma, an above knee amputation was performed because of the invasion of the neurovascular structures in the popliteal fossa.Results The patient died 11 months after the initial event from pulmonary and further brain metastases.Conclusion Brain metastases are seldom the primary factor in the management of advanced synovial sarcoma. Initially, the primary tumor was thought to be a benign cyst; we therefore recommend a biopsy/excision of lesions greater than 5 cm in size and with growth tendency to allow appropriate treatment.     

Retrospective analysis of the prevalence of asymptomatic cerebral aneurysm in 4518 patients undergoing magnetic resonance angiography--when does cerebral aneurysm develop?

The natural history of cerebral aneurysms was investigated by measuring the prevalence of incidentally found unruptured aneurysms in the general population and evaluating the characteristics including risk factors. 'De novo' formation of aneurysm was also demographically estimated. The prevalence of incidental aneurysm was evaluated among 4518 patients who underwent magnetic resonance (MR) angiography for various reasons in a neurosurgical institute. Double the number of patients were randomly selected from the remaining patients without aneurysm as the Control group so that sex and age group were matched to the Aneurysm group. 127 patients (2.8%) had diagnoses of aneurysm. The prevalence of asymptomatic aneurysm among middle-aged and elderly patients was predominant in women and increased with age in both sexes. Patients with aneurysms had significantly more hypertension and family history of subarachnoid hemorrhage compared to the controls. The prevalence was markedly increased in the 8th decade in men and the 7th decade in women, and new aneurysms seemed to develop predominantly around these decades. Cerebral aneurysms become detectable on MR angiography in the middle or later decades, and women tend to develop aneurysm earlier than men. Hypertension and family history of subarachnoid hemorrhage are probably risk factors for the development of aneurysm.     

Can hypocapnia reduce cerebral embolization during cardiopulmonary bypass?

BACKGROUND: Cerebral embolization is a major cause of central nervous dysfunction after cardiopulmonary bypass. Experimental studies demonstrate that reductions in arterial carbon dioxide tension (PaCO2) can reduce cerebral embolization during cardiopulmonary bypass. This study examined the effects of brief PaCO2 manipulations on cerebral embolization in patients undergoing cardiac valve procedures. METHODS: Patients were prospectively randomized to either hypocapnia (PaCO2 = 30 to 32 mm Hg, n = 30) or normocapnia (PaCO2 = 40 to 42 mm Hg, n = 31) before aortic cross-clamp removal. With removal of the aortic cross-clamp embolic signals were recorded by transcranial Doppler ultrasonography for the next 15 minutes. RESULTS: Despite significant differences in PaCO2, groups did not differ statistically in total cerebral emboli counts. The mean number of embolic events was 107 +/- 100 (median, 80) in the hypocapnic group and 135 +/- 115 (median, 96) in the normocapnic group, respectively (p = 0.315). CONCLUSIONS: Due to the high between-patient variability in embolization, reductions in PaCO2 did not result in a statistically significant decrease in cerebral emboli. In contrast to experimental studies, the beneficial effect of hypocapnia on cerebral embolization could not be demonstrated in humans.     

The diagnosis and treatment of severe cerebral fat embolism

Objective: To improve the diagnosis and treatment of severe cerebral fat embolism (SCFE). Methods - The data of nine patients with SCFE were retrospectively analyzed. The manifestations of the central nerve system, respiratory system and hemorrhage were recorded, at the same lime, accessory examination including arterial oxygen, fat macroglobules in venous blood and image examination was adapted. The patients were treated with exopexy, pharmocotherapy and oxygentherapy. Results: Two of the nine patients died of severe complications, the other seven recovered without severe sequela. Conclusions: Gurd standard should be improved for early diagnosis of SCFE. If svere complications can be prevented, patients who receive early treatment will have favourable prognosis.     

How do I select cerebral protection devices today?

The establishment of cerebral protection has matured conceptually and clinically in recent years. We have accepted that some type of cerebral protection is desirable. We have some choices in whether to use filters, proximal occlusion, or proximal occlusion with reversed flow. There are anatomical and clinical factors that drive the choice of cerebral protection devices. Certain practical applications of cerebral protection technologies can be made based upon clinical experience. Making carotid artery stenting (CAS) safer is the key to a broader application of CAS as a treatment method and optimal selection of atherosclerosis new cerebral protection devices helps to achieve that goal.     

Does hypothermia prevent cerebral ischaemia during cardiopulmonary bypass?

It is believed that moderate hypothermia (25-32 degrees C) during cardiopulmonary bypass provides cerebral protection by reducing the cerebral metabolic rate (CMRO2). Nevertheless episodes of ischaemia do occur and thus it has been suggested that cerebral oxygenation should be monitored by jugular venous oximetry. However, this technique is cumbersome and invasive. Near infrared spectroscopy (NIRS) provides a non-invasive assessment of cerebral oxygenation and this was used together with continuousjugular venous oximetry in 21 patients undergoing hypothermic cardiopulmonary bypass. During the hypothermic period, jugular venous oximetry indicated reduced oxygen extraction consistent with a reduction in CMRO2 (increase from 61 +/- 2.5% to 74 +/- 2.5%). In contrast, near infrared spectroscopy demonstrated increased oxygen extraction (HbO2 - 11.5 +/- 1 microM, HHb + 3.2 +/- 0.3 microM) and a fall in the cerebral concentration of oxidized cytochrome oxidase ( - 1.7 +/- 0.3 microM) indicating ischaemia. These results suggest that cerebral ischaemia occurs during hypothermic cardiopulmonary bypass with a spurious rise in jugular venous oxygen saturation, which represents arterio-venous shunting. Thus if hypothermia does facilitate cerebral protection it does not appear to be a direct result of a reduction in CMRO2 and oxygen requirement.     

Which surgery for drooling in patients with cerebral palsy?

Background

Surgery for drooling in patients with cerebral palsy should not produce xerostomia in order not to deteriorate speech, taste, or the status of oral hygiene. It must be a compromise between drooling and quality of life. The purpose of the present report is to describe our surgical strategy that respects the above principles.

Materials and Methods

Patients were initially operated on depending on the drooling severity. The results were evaluated according to the frequency of residual drooling and the Thomas-Stonel and Greenberg classification. Quantitative assessment was proposed 6 months after surgery. The data have been compared using the nonparametric Wilcoxon matched-pairs test.

Results

Thirty-five patients underwent surgery between 1991 and 2012. Owing to incomplete data, only 31 patients could be included, aged 5 to 24 years (mean: 12 years). All patients underwent surgery on the submandibular duct. Only 16 patients underwent a simultaneous surgery on the parotid duct. Six patients were reoperated: 3 because of an insufficient result and 3 because of a surgical complication. Changes/Day ranged from 1 to 7 (median: 3) before surgery and 0 to 2 (median: 1) after surgery (p < 0.01). Number of bibs/day ranged from 0 to 30 (median: 4) before surgery and 0 to 4 (median: 1) after surgery (p < 0.01). No dental deterioration and no caries occurred after surgery.

Conclusion

Good results for drooling can be obtained with a simple surgical procedure on the submandibular ducts, maintaining quality of life, avoiding deterioration of speech, taste, and the status of oral hygiene.