Three cases of brain hydatidosis in North Khorasan, Iran.

Cystic hydatidosis is a serious public health problem in Iran. Although cysts can develop in almost all organs and the brain cysts are very rare. Here, we present 3 confirmed cases of brain hydatidosis and the patients who underwent successful surgery. Pathological examinations demonstrated the presence of cystic hydatidosis.

High resolution 3-Dimensional imaging of the human cardiac conduction system from microanatomy to mathematical modeling.

Cardiac arrhythmias and conduction disturbances are accompanied by structural remodelling of the specialised cardiomyocytes known collectively as the cardiac conduction system. Here, using contrast enhanced micro-computed tomography, we present, in attitudinally appropriate fashion, the first 3-dimensional representations of the cardiac conduction system within the intact human heart. We show that cardiomyocyte orientation can be extracted from these datasets at spatial resolutions approaching the single cell. These data show that commonly accepted anatomical representations are oversimplified. We have incorporated the high-resolution anatomical data into mathematical simulations of cardiac electrical depolarisation. The data presented should have multidisciplinary impact. Since the rate of depolarisation is dictated by cardiac microstructure, and the precise orientation of the cardiomyocytes, our data should improve the fidelity of mathematical models. By showing the precise 3-dimensional relationships between the cardiac conduction system and surrounding structures, we provide new insights relevant to valvar replacement surgery and ablation therapies. We also offer a practical method for investigation of remodelling in disease, and thus, virtual pathology and archiving. Such data presented as 3D images or 3D printed models, will inform discussions between medical teams and their patients, and aid the education of medical and surgical trainees.

Is There Any Benefit of Neuromonitoring During Descending and Thoracoabdominal Aortic Aneurysm Repair?

OBJECTIVE: Paraplegia remains the most feared and a devastating complication after descending and thoracoabdominal aneurysm operative repair (DTA and TAAAR). Neuromonitoring, particularly use of motor-evoked potentials (MEPs), for this surgery has gained popularity. However, ambiguity remains regarding its use and benefit. We systematically reviewed the literature to assess the benefit and applicability of neuromonitoring in DTA and TAAAR. METHODS: Electronic searches were performed on 4 major databases from inception until February 2014 to identify relevant studies. Eligibility decisions, method quality, data extraction, and analysis were performed according to predefined clinical criteria and end points. RESULTS: Among the studies matching our inclusion criteria, 1297 patients had MEP monitoring during DTA and TAAAR. In-hospital mortality was low (6.9% ± 3.6). Immediate neurological deficit was low (3.5% ± 2.6). In one third of patients (30.4% ± 14.2), the MEPs dropped below threshold, which were 30.4% and 29.4% with threshold levels of 75% and 50%, respectively. A range of surgical techniques were applied after reduction in MEPs. Most patients whose MEPs dropped and remained below threshold had immediate permanent neurological deficit (92.0% ± 23.6). Somatosensory-evoked potentials were reported in one third of papers with little association between loss of somatosensory-evoked potentials and permanent neurological deficit (16.7% ± 28.9%). CONCLUSIONS: We demonstrate that MEPs are useful at predicting paraplegia in patients who lose their MEPs and do not regain them intraoperatively. To date, there is no consensus regarding the applicability and use of MEPs. Current evidence does not mandate or support MEP use.

Setting up and utilizing a service for measuring perioperative transcranial motor evoked potentials during thoracoabdominal aortic surgery and thoracic endovascular repair.

OBJECTIVES: Paraplegia is a complication that may occur following surgery or endovascular stenting of thoracic and thoracoabdominal aortic pathology. Measuring transcranial motor evoked potentials (tcMEPs) has been shown to provide a reliable measure of spinal cord function during such procedures allowing interventions to protect cord function. In the spirit of sharing experience and eliminating the learning curve for others, this manuscript describes our experience of setting up a service for tcMEP monitoring as well as the documents and algorithms for measuring, recording and acting on the patient data, the so-called 'MEP Pathway'. METHODS: Recording and interpretation of tcMEP during thoracoabdominal aortic intervention requires training of staff and close team working in the operating theatre and postoperative intensive care unit. Providing consistent, reliable, specific and sensitive information on spinal cord function and its safe and effective use to alter patient outcomes requires a protocol. The MEP pathway was developed by medical and paramedical staff at our institution based on clinical experience and literature reviews over a 1-year period (2012-2013). RESULTS: The tcMEP pathway comprises six documents that guide staff in: (a) assessing suitability of patients, (b) setting up hardware, (c) preparing algorithms for management, (d) documenting intervention (left heart bypass, cardiopulmonary bypass or endovascular stenting) as well as (e) documenting postoperative intensive care processes. CONCLUSIONS: The tcMEP pathway acts as a guide for safe introduction and use of tcMEPs in thoracoabdominal aortic interventions. tcMEP-led guidance of intraoperative and postoperative management in thoracic aortic surgery is an important adjunct in caring for this patient group.

Novel application of acetazolamide to reduce cerebrospinal fluid production in patients undergoing thoracoabdominal aortic surgery.

OBJECTIVES: Paraplegia is a rare but devastating complication, which may follow thoracoabdominal aortic surgery. Many adjuncts have been developed to reduce this risk including cerebrospinal fluid (CSF) drainage. Acetazolamide (carbonic anhydrase inhibitor) is a drug used to counteract mountain sickness and one of its effects is to reduce CSF production. Here, we report its first postoperative application in thoracoabdominal surgery with the aim of reducing cerebrospinal cord perfusion pressure and reducing risk of paraplegia. METHODS: We retrospectively reviewed 6 patients who have been treated with this drug between 2011 and 2012 who were undergoing thoracoabdominal aortic surgery. Our indications were decided to include: (i) patients in whom a spinal drain could not be positioned; (ii) patients with blood-stained CSF; (iii) patients in whom the volume of CSF drained was outside guidelines; (iv) patients in whom CSF pressure was elevated; (v) patients with excessive vasopressor usage and (vi) patients with postoperative neurological dysfunction as measured by motor-evoked potentials or clinical examination. All were given 500 mg intravenous acetazolamide, not more than eight hourly, for a duration dependent on response. RESULTS: In the 6 patients, 2 received a single dose of the drug and responded by an immediate drop in intracranial pressure (ICP) pressure. Of the 4 who received multiple doses of the drug, 1 had an immediate decline in ICP after each of the first six doses, while 3 had no discernable response. CONCLUSIONS: This is the first report of the efficacy of acetazolamide in reducing CSF production and lowering ICP during thoracoabdominal aortic surgery. We believe that its use will be beneficial in the 6 patient groups described. Our experience suggests there are 'responders' and 'non-responders', the characteristics of whom are yet to be defined. Its efficacy in reducing not just CSF volume and ICP but also clinically relevant morbidity such as paraplegia, is the subject of a planned randomized controlled trial. This report serves to raise awareness of the possible efficacy of this drug when normal management strategies are limited or exhausted.