Thoracoscopic and laparoscopic oesophagectomy improves the quality of extended lymphadenectomy

BACKGROUND

Oesophagectomy with extended lymphadenectomy carries considerable morbidity due to parietal trauma. It is also technically extremely demanding because the difficult access even through a large thoracotomy requires the use of long instruments to reach the deepest recess in the chest cavity. Since the first thoracoscopic oesophagectomy reported by Cuschieri et al. [1] in 1992, different minimally invasive approaches have been proposed [2-12]. The aim of this video is to show the accurate and relative ease of an entirely thoracoscopic and laparoscopic oesophagectomy with an extended lymph node dissection of mediastinum in prone position (thoracoscopically) and celiac trunk (laparoscopically).

METHODS

Oesophagectomy by thoracoscopy, laparoscopy and cervicotomy was proposed in a 63-year-old man with a lower third oesophageal cancer. General anaesthesia was performed with a double-lumen endotracheal tube and the patient was placed in prone position. Surgeons were positioned at the right side of the patient. Only three trocars were needed. A 10 mm 30-degree angled scope was inserted in the 7th intercostal space on the posterior axillary line and the remaining two 5 mm trocars were inserted in the 5th and 9th intercostal spaces on the posterior axillary line. Prone position allows an excellent visibility of the operative field even in an only partially deflated lung. In order to achieve a good exposure, transitory pneumothorax with CO2 (14 mmHg) was performed. The mediastinal pleura overlying the oesophagus was incised and the arch of azygos vein was isolated, ligated and divided. The oesophagus was circumferentially mobilized from the thoracic inlet down to oesophageal hiatus. Para oesophageal and subcarinal lymph nodes were dissected so as to remain in block with the surgical specimen. A 28 F chest tube was inserted in the 8th intercostal space on the anterior axillary line. In the second stage the patient was placed in supine position and pneumoperitoneum was established. Five trocars were placed along an ideal semicircular line, with the concavity facing the subcostal margin and a 30-degree angled laparoscope was used. The lesser omentum was widely opened up the right pillar of the hiatus. Mobilization of the greater curvature of the stomach was performed preserving the right gastroepiploic artery. A wide Kocher maneuver was performed. Celiac lymphadenectomy started with skeletonization of the hepatic artery until the root of left gastric artery was reached. This artery and the left gastric vein were dissected, clipped and sectioned. All fatty tissue and lymph nodes along hepatic artery, left gastric artery and celiac trunk were resected in block with the surgical specimen. Multiple applications of a linear endoscopic stapler were used to create the gastric tube. Finally the distal oesophagus was dissected, until the thoracoscopic dissection field was joined. In the third stage a left lateral cervicotomy was performed and the cervical oesophagus was dissected down to the thoracoscopic dissection plane. Oesophagus and stomach were delivered through the cervical incision and an oesophagogastric anastomosis was created by a linear stapler technique. Cervical and abdominal drainages were installed.

RESULTS

The total operative time was 271 minutes (thoracoscopy: 106 minutes, laparoscopy 120 minutes and cervicotomy 45 minutes) and blood loss was about 100 ml. Histological examination demonstrated a squamous cell carcinoma. Both margins of resection were free of tumour and 29 lymph nodes were retrieved. The final stage was IIA (pT3N0Mx).

CONCLUSIONS

Thoracoscopic and laparoscopic oesophagectomy with extended lymphadenectomy is technically feasible and safe. Thoracoscopic oesophagectomy in prone position improves the quality of dissection because: The oesophagus and aorto-pulmonary window are reached under excellent visibility, despite a partially deflated lung, which because of gravity will always remain out of harm's way. For the same reason small to moderate bleeding will not obscure the operative field. Dissection with the long endoscopic instruments is more accurate due to the support provided by the entrance site at the parietal level and the ergonomic position of surgeon. This article contains a supplementary video.

Screen-and-treat colposcopy as public health strategy for cervical cancer early detection in high-risk population: The experience of the Centro de Estudios y Prevencion del Cancer (CEPREC) in indigenous population of Southern Mexico

5012

Background: The incidence of cervical cancer in Mexico remains high, due to ineffective Papanicolau smear screening, social, educational, cultural and financial issues. Southern Mexico is a region with a high incidence of cervical cancer. CEPREC has designed educational, preventive and early cancer detection programs in that population (Onkologie 27:211). We propose screen-and-treat colposcopy for cervical cancer prevention as public health strategy in selected high-risk population. This study evaluates the feasibility and acceptability of this approach through an educational program. Methods: From 12/2002 to 12/2005, women living in Southern Mexico were educated about cervical cancer and its prevention and were offered colposcopy either in CEPREC facilities or in ambulatory clinics. Colposcopy diagnosis and cervical cytology were established according to the 1990 IFCPC criteria and the 2001 Bethesda System, respectively. A cone biopsy was indicated in patients diagnosed as having human papilloma virus (HPV), cervical intraepithelial neoplasia (CIN 1, CIN 2, CIN 3), or carcinoma. Patients diagnosed as having HPV, CIN 2 and CIN 3 were treated by large loop excision of the transformation zone under local anesthesia. Results: 8281 women (median age 39 years, range: 14–87) were evaluated. 5645 (68%) of them underwent colposcopy in ambulatory clinics. 1171 (14%) women were illiterates and the highest education level was 9 years in 4881 (59%). Median age at first intercourse and first Papanicolau smear were 19 and 29 years, respectively. 4251 (51%) women had vaginal symptoms before colposcopy. Abnormal colposcopy (HPV, CIN 1, CIN 2 or CIN 3), was diagnosed in 1073 (13%) patients and 9 (<1%) had carcinoma. 238 (22%) of them were treated on site. Low-Grade (n = 190) (80%), and high-grade squamous intraepithelial lesions (n = 48) (20%), were diagnosed in those patients. Conclusions: Screen-and-treat colposcopy is a feasible public health strategy with high acceptability in selected high-risk population and could be an alternative to cytology-based screening programs.

No significant financial relationships to disclose.

Recurrent ovarian dysgerminoma after laparoscopy

To our knowledge, recurrent dysgerminoma at the site of tumor removal by laparoscopy in a patient with stage IA disease has not been previously reported. A woman with ovarian dysgerminoma treated by laparoscopy and tumor removed through the cul-de-sac recurred the 17 months later at the site of tumor removal. She was successfully treated with etoposide, bleomycin, and cisplatin chemotherapy with complete response. This case illustrates the potential for surgical site implant of an ovarian dysgerminoma; surgeons should follow strict guidelines when performing laparoscopic procedures for ovarian malignancies in order to prevent this type of incident.

Cyclical upregulated iNOS and long-term downregulated nNOS are the bases for relapse and quiescent phases in a rat model of IBD

We previously reported that indomethacin induces a chronic intestinal inflammation in the rat where the cyclical characteristic phases of Crohn's disease are manifested with a few days' interval and lasting for several months: active phase (high inflammation, hypomotility, bacterial translocation) and reactive phase (low inflammation, hypermotility, no bacterial translocation). In this study, we investigated the possible role of both constitutive and inducible isoforms of nitric oxide (NO) synthase (NOS) and cyclooxygenase (COX) in the cyclicity of active and reactive phases in rats with chronic intestinal inflammation. Rats selected at either active or reactive phases and from 2 to 60 days after indomethacin treatment were used. mRNA expression of both constitutive and inducible NOS and COX isoforms in each phase was evaluated by RT-PCR and cellular enzyme localization by immunohistochemistry. The effects of different COX and NOS inhibitors on the intestinal motor activity were tested. mRNA expression of COX-1 was not modified by inflammation, whereas mRNA expression of neuronal NOS was reduced in all indomethacin-treated rats. In contrast, NOS and COX inducible forms showed a cyclical oscillation. mRNA expression and protein of both iNOS and COX-2 increased only during active phases. The intestinal hypomotility associated with active phases was turned into hypermotility after the administration of selective iNOS inhibitors. Sustained downregulation of constitutive NOS caused hypermotility, possibly as a defense mechanism. However, this reaction was masked during the active phases due to the inhibitory effects of NO resulting from the increased levels of the inducible NOS isoform.

[Preclinical diagnosis of the familial nephropathy associated to hyperuricemia]

We describe one patient with the pre-symptomatic diagnosis of the disease named afamilial nephropathy associated to hyperuricemia)) (OMIM 162000; FJHN). This is a hereditary disease, autosomic dominant, characterized by its progression to renal insufficiency. Several mutations in the gene that codifies uromodulin or Tannn-Horsfall protein (UMOD) have been identified in some families. The clinical presentation is heterogeneous. In some cases the disease appears as juvenile hyperuricemia due to a diminished renal urate excretion, with or without gout, but in some other cases the first manifestation is renal insuffciency. The study of the UMOD gene shows that patient is heterozygous for the mutation C869 --> A, which results in C255Y change, and enabled to establish the diagnosis of FJHN. This patient shows the possibility to identify the genetic alteration associated to FJHN in early stages. This fact implies a clinical follow-up and eventual treatment to reduce the inexorable progression to renal insuffciency.

Recurrent ovarian dysgerminoma after laparoscopy

To our knowledge, recurrent dysgerminoma at the site of tumor removal by laparoscopy in a patient with stage IA disease has not been previously reported. A woman with ovarian dysgerminoma treated by laparoscopy and tumor removed through the cul-de-sac recurred the 17 months later at the site of tumor removal. She was successfully treated with etoposide, bleomycin, and cisplatin chemotherapy with complete response. This case illustrates the potential for surgical site implant of an ovarian dysgerminoma; surgeons should follow strict guidelines when performing laparoscopic procedures for ovarian malignancies in order to prevent this type of incident.

Effect of H1- and H2-receptor antagonists on the hemodynamic changes induced by the intravenous administration of ketamine in sevoflurane-anesthetized cats

OBJECTIVE

The anesthetic ketamine has been reported to cause both an increase of the plasma histamine concentration, notably in cats, and a cardiovascular depression. The latter has been described in humans and in other species. However the relevance of the histamine fluctuation for the ketamine-induced hemodynamic changes has not been determined.

SUBJECTS AND TREATMENT

We studied the contribution of histamine to the hemodynamic effects induced by IV ketamine (7 mg/kg) in 12 sevoflurane anesthetized cats, of which half had been pre-treated with combined H(1)- and H(2) -receptor antagonists.

METHODS

The mean arterial pressure (MAP) and the heart rate (HR) from both untreated (group C) and pre-treated (group AH) cats were recorded before and after the ketamine administration. The plasma histamine concentration was also measured.

RESULTS

Plasma histamine fluctuations in the control and the antihistamine-treated group followed a similar pattern (no statistical differences); an initial rise that peaked 2 min after ketamine injection (from 0.63 +/- 0.11 ng/ml to 2.22 +/- 0.69 ng/ml in the C group, and from 0.71 +/- 0.10 ng/ml to 1.09 +/- 0.28 ng/ml in the AH group) followed by an immediate decrease in plasma concentrations. As for the hemodynamic variables under analysis, in the control group ketamine administration was followed by an early 30.3 +/- 8.1% reduction (p < 0.005) in the MAP with no associated changes in the HR. In the antihistamine pre-treated group, ketamine caused a further decrease of the MAP (41.7 +/- 2.3%), and a significant (p < 0.01) 11.6 +/- 2.9% reduction of the HR.

CONCLUSION

Ketamine in anesthetized cats triggers histamine release and induces cardiovascular depression. The depression is more pronounced under the blockade of histamine activity through histamine receptor antagonists.

[Influence of maize kernel hardness on flour hydration and cooking properties]

Knowledge of the association between cooking properties and endosperm hardness may help nutritionist and processors to select raw materials for preparing maize based food products, particularly those eaten as cooked dispersions. Seven commercial maize cultivars differing in hardness were selected to evaluate endosperm hardness on the kernels and some characteristics such as composition and hydration and cooking properties on the grits obtained from those maizes. Results show that the differences in endosperm hardness (directly related to grits protein content) can explain the differences in swelling and amylographic consistencies values. Cultivars with the hardest endosperm show the lowest values at high temperature. They also show the lowest amylographic consistencies. On the other hand softer endosperms present the highest swelling power and the highest amylographic consistencies. These differences are attributed to the restriction for starch swelling caused by the protein matrix. Endosperm hardness measurements and swelling power at 95 degrees C, can be useful to select cultivars that are going to be used to prepare maize based foods like atoles, polenta, etc.

QTLs for drought escape and tolerance identified in a set of random introgression lines of rice

A large set of 254 introgression lines in an elite indica genetic background were evaluated for grain yield (GY) and related traits under the irrigated (control) and drought (stress) conditions in two consecutive years for genetic dissection of adaptive strategies of rice to water stress. A total of 36 quantitative trait loci (QTLs) affecting heading date (HD), plant height (PH), GY and yield components were identified and most QTLs showed pronounced differential expression either qualitatively or quantitatively in response to drought. These QTLs could be grouped into three major types based on their behaviors under control and stress conditions. Type I included 12 QTLs that expressed under both the stress and non-stress conditions. Type II comprised 17 QTLs that expressed under irrigation but not under stress. Type III included seven QTLs that were apparently induced by stress. The observation that the Lemont (japonica) alleles at all HD QTLs except QHd5 resulted in early heading under stress appeared to be responsible for the putative adaptation of Lemont to drought by escaping, whereas the Teqing (indica) alleles at most PH/GY QTLs were consistently associated with increased yield potential and trait stability and thus contributed to DT. Our result that most DT QTLs were non-allelic with QTLs for drought escaping suggests that the two adaptive strategies in the parental lines are under possible negative regulation of two largely non-overlapping genetic systems.

Multimedia article. Entirely thoracoscopic pneumonectomy using the prone position: a new technique

BACKGROUND

Reports on video-assisted pneumonectomy have remained scarce, despite early demonstration of its technical feasibility. A totally videothoracoscopic pneumonectomy was first reported by Conlan and Sandor. The patient in this report was positioned in the full lateral position. In this video, we report a totally videothoracoscopic left-side pneumonectomy with the patient in prone position.

METHODS

A 49-year-old man was admitted to our hospital for a bifocal cancer of the left lower lung lobe (LLL) and the cervical esophagus. The preoperative workup included a chest computed tomography (CT) scan showing a 3-cm mass of the laterobasal segment of the LLL, with retrotumoral atelectasis, lymph nodes smaller than 1 cm in diameter at the aortopulmonary window and under the carena, and finally posterolateral adherences between the parietal and the visceral pleura. Flexible bronchoscopy confirmed the presence of a bronchial tumor at the offspring of the apical bronchus of the LLL. Biopsy showed invasive adenocarcinoma, and a CT scan of the neck and head was significant for tumoral infiltration of the cervical esophagus and retropharyngeal space. Gastroscopy showed a stenosis of the cervical esophagus and hypopharynx. Biopsy showed spinocellular epithelioma, but CT scan of the abdomen and bone scintigraphy did not show metastatic disease. A position emission tomography (PET) scan confirmed the findings of the CT scan. Pneumonectomy and esophagectomy by thoracoscopy, laparoscopy, and cervicotomy were proposed. The purpose of this video is to show the details of the thoracoscopic technique with the patient in the prone position.

RESULTS

After induction of general anesthesia, a double-lumen endotracheal tube was placed. The patient was subsequently placed and strapped in a prone position. The surgical team was placed to the left of the patient. A 10-mm trocar was placed in the seventh intercostal space on the posterior axillary line, and a 30 degrees angled videoscope was introduced. Three additional 5-mm trocars were placed at the same level in the 5th, 9th, and 11th intercostal spaces on the posterior axillary line. The mediastinal pleura was opened just ventral to the aorta. The first structure identified was the left main bronchus, which was dissected free and transected with a linear stapler (blue load). The aortopulmonary window became immediately visible. Clearance of this window's lymphoglandular tissue showed, bottom to top, the inferior pulmonary vein, the superior pulmonary vein, and the pulmonary artery. These vascular structures were carefully dissected free with the cautery hook and transected with a vascular linear stapler (white load). The lung was freed entirely tend placed in a retrieval bag for later transhiatal extraction during the laparoscopic phase of the esophagectomy. The intraoperative time for the pneumonectomy was 146 min, and intraoperative blood loss was 30 ml. The pathology report confirmed the presence of invasive, poorly differentiated adenocarcinoma. The bronchial section was free of tumor. One intrapulmonary lymphnode (N1) was positive, whereas all 10 N2 and N3 nodes harvested were free of disease. The tumor was thus staged as IIB (pT2N1Mx). The esophagetomy specimen showed fairly wide differentiated keratinizing of the spinocellular epithelioma with invasion of both pyriform sinuses and both sides of the glottis.

CONCLUSIONS

First described by Cuschieri et al. in 1992, the prone position for thoracoscopy allows for a more direct approach to the aortopulmonary window under excellent visual and ergonomic circumstances. Dissection of the hilar larger vessels and performance of lymphnode sampling appear more straightforward because with this technique, the lung is kept out of harm's way, thanks to gravity.

Controlling two-center interference in molecular high harmonic generation

We experimentally investigate the process of intramolecular quantum interference in high-order harmonic generation in impulsively aligned CO2 molecules. The recombination interference effect is clearly seen through the order dependence of the harmonic yield in an aligned sample. The experimental results can be well modeled assuming that the effective de Broglie wavelength of the returning electron wave is not significantly altered by the Coulomb field of the molecular ion. We demonstrate that such interference effects can be effectively controlled by changing the ellipticity of the driving laser field.

Accumulation of the compatible solutes, glycine-betaine and ectoine, in osmotic stress adaptation and heat shock cross-protection in the biocontrol agent Pantoea agglomerans CPA-2

AIMS

The effect of modifying the water activity (a(w)) of Pantoea agglomerans growth medium with the ionic solute NaCl on water stress resistance, heat-shock survival and intracellular accumulation of the compatible solutes glycine-betaine and ectoine were determined.

METHODS AND RESULTS

The bacterium was cultured in an unmodified liquid medium or that modified with NaCl to 0.98 and 0.97 a(w), and viability of cells evaluated on a 0.96 a(w)-modified solid media to check water stress tolerance. Cells grown under ionic stress had better water stress tolerance than control cells. These cells also had cross-protection to heat stress (30 min, 45 degrees C). The modified cells accumulated substantial amounts of the compatible solutes glycine-betaine and ectoine in contrast to the control cells, which contained little or none of these two compounds.

CONCLUSIONS

Improvement in osmotic and thermal tolerance of cells of the biocontrol agent P. agglomerans by modifying growth media with the ionic solute NaCl was achieved. The compatible solutes glycine-betaine and ectoine play a critical role in environmental stress tolerance improvement.

SIGNIFICANCE AND IMPACT OF THE STUDY

This approach provides a method for improving the physiological quality of inocula and could have implications for formulation and shelf-life of biocontrol agents.

High-strength apatitic cement by modification with superplasticizers

This study reports on a novel method to improve the strength of apatitic bone cements. The liquid phase of Biocement-H was modified with commercial superplasticizers. The results showed that small additions, i.e. 0.5 vol%, in the aqueous liquid phase improved the maximum compressive strength of Biocement-H (35 MPa) by 71%, i.e. 60 MPa. Moreover, the addition of high amounts of superplasticizers, i.e. 50 vol.%, allowed for a significant reduction of the liquid-to-powder ratio from 0.32 to 0.256 mL/g, without affecting the maximum strength and/or the workability of the cement. These results open up new ways to develop injectable and high-strength apatitic bone cements for load-bearing applications.

Global iron connections between desert dust, ocean biogeochemistry, and climate

The environmental conditions of Earth, including the climate, are determined by physical, chemical, biological, and human interactions that transform and transport materials and energy. This is the "Earth system": a highly complex entity characterized by multiple nonlinear responses and thresholds, with linkages between disparate components. One important part of this system is the iron cycle, in which iron-containing soil dust is transported from land through the atmosphere to the oceans, affecting ocean biogeochemistry and hence having feedback effects on climate and dust production. Here we review the key components of this cycle, identifying critical uncertainties and priorities for future research.

Deep Brain Stimulation in Intraoperative MRI Environment - Comparison of Imaging Techniques and Electrode Fixation Methods

We performed 118 consecutive DBS cases from November 1999 to June 2002. Intraoperatively there were 10 cases studied with fluoroscopy, 73 with 0.2 Tesla (T) MRI and 35 with 1.5 T MRI. Ten electrodes were secured by Medtronic caps, 25 by methyl methacrylate with titanium miniplates, and 82 by Navigus caps. The 3-dimensional displacement between the planned target and actual electrode position (3DD) was determined by fusing the postoperative MRI with the preoperative imaging. The 3DD for using Medtronic caps, methyl methacrylate with miniplates, and Navigus caps were 4.80 +/- 3.16, 2.64 +/- 1.26 and 2.23 +/- 1.15 mm (mean +/- SD), respectively. Navigus caps had statistically significant accuracy (P = 0.03) in holding the electrode when compared with Medtronic caps, and it facilitated electrode revision. The fixation devices significantly affect the final vertical position of the electrode. The 3DD for fluoroscopy, 0.2 T and 1.5 T MRI cases were 4.80 +/- 3.16, 2.31 +/- 1.21 and 2.34 +/- 1.14 mm (mean +/- SD), respectively. No statistically significant difference (P = 0.91) in 3DD was demonstrated between 0.2 T and 1.5 T MRI cases. The presence of intraoperative 1.5 T MRI allowed near real-time electrode position confirmation and early detection of hemorrhagic complications. Satisfactory microelectrode recording was feasible in low-field 0.2 T and high-field 1.5 T MRI environments. Further studies on performing DBS in real-time intraoperative MRI are warranted.

Laparoscopic left lateral hepatic lobectomy for metastatic colorectal tumor

BACKGROUND

The growth of experience in laparoscopic surgery, technological improvements in laparoscopic instruments, and the application of laparoscopy to oncology surgery are responsible for the new challenge of laparoscopic liver surgery. Several series of laparoscopic liver resections have been reported, and these series have shown the feasibility of resections. The first anatomical laparoscopic liver resection was a left lateral segmentectomy, reported in 1996 by Azagra et al. due to favorable anatomy of this hepatic segment for a totally laparoscopic approach.

METHODS

This video shows a left lateral hepatic lobectomy (bisegmentectomy 2-3) by a total laparoscopic approach in a 56-year-old woman who presented with a metastatic tumor from operated colorectal cancer. A CO(2) pneumoperitoneum was induced with a Veress needle and abdominal pressure was maintained at 12 mmHg. Five trocars were placed along an ideal semicircular line, with the concavity facing the right subcostal margin, and a 30 degrees angled laparoscope was used. A retraction of round ligament with suture was performed to obtain exposure of the inferior face of liver. The left hepatic pedicle was dissected in close vicinity with the portal branch. Segmental vascular structures and bile ducts of segments 3 and 2 were progressively and intraparenchymatously identified, clipped, and sectioned. A Pringle's maneuver was not necessary. The dissection line was demarcated on the liver with monopolar cautery, and liver parenchymal transection was obtained with an ultrasound scalpel (Ultracision, Ethicon Endosurgery). Finally, the left hepatic vein was sectioned with a linear vascular endostapler (Ethicon Endosurgery). Extraction of specimen was performed using a plastic bag through an enlarged trocar site.

RESULTS

The operative time was 110 min, and blood loss was zero. The postoperative period was uneventful, the length of hospital stay was 5 days, and the patient returned to normal activity 1 week postoperatively. The surgical margins of specimen were free of disease.

CONCLUSIONS

Laparoscopic left lateral lobectomy of the liver is feasible and safe in patients with isolated malignant disease of the left lateral segment. This approach reduces blood loss and postoperative hospital stay, and it has a better cosmetic result.

Bartonelosis (Carrion's Disease) in the pediatric population of Peru: an overview and update

Bartonellosis, or Carrion's Disease, is an endemic and reemerging disease in Peru and Ecuador. Carrion's Disease constitutes a health problem in Peru because its epidemiology has been changing, and it is affecting new areas between the highland and the jungle. During the latest outbreaks, and previously in endemic areas, the pediatric population has been the most commonly affected. In the pediatric population, the acute phase symptoms are fever, anorexia, malaise, nausea and/or vomiting. The main signs are pallor, hepatomegaly, lymphadenopathies, cardiac murmur, and jaundice. Arthralgias and weight loss have also commonly been described. The morbidity and mortality of the acute phase is variable, and it is due mainly to superimposed infections or associated respiratory, cardiovascular, neurological or gastrointestinal complications. The eruptive phase, also known as Peruvian Wart, is characterized by eruptive nodes (which commonly bleed) and arthralgias. The mortality of the eruptive phase is currently extremely low. The diagnosis is still based on blood culture and direct observation of the bacilli in a blood smear. In the chronic phase, the diagnosis is based on biopsy or serologic assays. There are nationally standardized treatments for the acute phase, which consist of ciprofloxacin, and alternatively chloramphenicol plus penicillin G. However, most of the treatments are based on evidence from reported cases. During the eruptive phase the recommended treatment is rifampin, and alternatively, azithromycin or erythromycin.

Functional Neurosurgery in the MRI Environment

OBJECTIVE

The purpose of this study was to evaluate the feasibility of microelectrode recording, electrical stimulation, and electrode position checking during functional neurosurgical procedures (DBS, lesion) in the interventional magnetic resonance imaging (iMRI) environment.

METHODS

Seventy-six surgical procedures for DBS implant or radiofrequency lesion were performed in an open 0.2 T MRI operating room. DBS implants were performed in 54 patients (72 surgical procedures) and unilateral radiofrequency lesions in three for a total of 76 surgeries in 57 patients. Electrophysiological studies including macrostimulation and microelectrode recordings for localization were obtained in the 0.5 to 10 mT fringes of the magnetic field in 51 surgeries. MRI confirmation of the electrode position during the procedure was performed after electrophysiological localization.

RESULTS

The magnetic field associated with the MRI scanner did not contribute significant noise to microelectrode recordings. Anatomical confirmation of electrode position was possible within the MRI artifact from the DBS hardware. Symptomatic hemorrhage was detected in two (2.6 %) patients during the operation. Image quality of the 0.2 T MRI scan was sub-optimal for anatomical localization. However, image fusion with pre-operative scans permitted excellent visualization of the DBS electrode tip in relation to the higher quality 1.5 T MRI anatomical scans.

CONCLUSION

This study shows that conventional stereotactic localization, microelectrode recordings, electrical stimulation, implant of DBS hardware, and radiofrequency lesion placement are possible in the open 0.2 T iMRI environment. The convenience of having an imaging modality that can visualize the brain during the operation is ideal for stereotactic procedures.

Prevalence of delirium in a geriatric convalescence hospitalization unit: patient's clinical characteristics and risk precipitating factor analysis

The aim was to evaluate the prevalence of delirium among patients discharged from an acute care hospital and admitted to a geriatric convalescence unit (GCU), and to analyze patient's characteristics and risk precipitating factors. Sixty-eight patients were analyzed during a 2-week period. The confusion assessment method (CAM) was used to detect delirium. The precipitating factors evaluated were: major surgery-intensive care unit(ICU) stay, pulmonary and heart failure, acute infections, metabolic disorders/anemia,psychoactive medications, other drugs, severe pain, changing environmental influences and others. According to CAM, fifteen patients presented delirium (22%), and in 14 of them(93.3 %) the delirium was developed before admission at GCU. The precipitating factors in the studied population were the following: changing environmental influences in 66 patients(97%) (15 with delirium and 51 without delirium); other drugs 56 (82.3 %) (11 vs. 45);others 56 (82.3%) (9 vs. 24); psychoactive medications 50 (73.5%) (12 vs. 38); acute infections 48 (70.5 %) (13 vs. 35); metabolic disorders/anemia 40 (58.8 %) (9 vs. 31); major surgery-ICU stay 28 (41 .1%) (8 vs. 20); severe pain 26 (38.2%) (6 vs. 20); pulmonary and heart failure 22 (32.3%) (5 vs. 17). The univariant analysis showed that, none of the precipitating factors studied was significantly related to delirium. Seventy-two patients (91.1%) had simultaneously >3 precipitating factors. There were 16 patients with >6 precipitating factors, 7 of 15 with delirium and 9 of the 53 without delirium (46.6 % vs 16.9 %) (p < 0.05). The prevalence of delirium has been 22 %. Most of the patients had developed delirium before the admission at GCU. A high proportion of patients had >3 precipitating factors. In the study the presence of > 6 precipitating factors simultaneously has been significantly related to delirium.