Characterization of Hemorrhagic Complications after Surgery for Temporal Lobe Epilepsy

OBJECTIVES

To assess the significance of symptomatic hemorrhagic complications occurring after different temporal resections for temporal lobe epilepsy (TLE) and to compare this data to findings with postoperative hematomas after temporal surgery for mostly glial or metastatic tumors.

PATIENTS AND METHODS

Patient charts were retrospectively reviewed for 442 patients who underwent surgery for refractory TLE between 1995 and 2000. Procedures were 247 transsylvian amygdalohippocampectomies (AH), 40 transcortical AH, 57 anterior temporal lobectomies (ATL), 23 lesionectomies plus AH, and 75 lesionectomies without AH. All patients with delayed awakening or new neurological deficits due to hemorrhages were included in the study. An identical procedure was performed to detect symptomatic hemorrhages after 208 procedures for temporal tumor resection during the same time period.

RESULTS

Symptomatic postoperative hemorrhages were found in 17 patients (3.8 %) undergoing epilepsy surgery, while the incidence was 3.0 % in a group with space-occupying temporal tumors (six patients). Hemorrhages showed a characteristic distribution after epilepsy surgery: in eight patients they were located remote from the site of surgery in the upper cerebellar vermis and foliae. Five typical hemorrhages associated with dysphasia were found in the left frontal operculum, only three patients had hematomas in the resection cavity, and one was located epidurally. Two patients had more than one location of hemorrhage. Transsylvian AH and ATL had a similar risk for postoperative hemorrhage, whereas none was found after lateral lesionectomies or transcortical AH. Intraoperative manipulations were associated with opercular hemorrhages; the only predisposing factor for resection site hematomas was older age, whereas cerebellar hemorrhages were associated with cerebrospinal fluid (CSF) loss during AH and ATL. There was no mortality in the TLE group, and 0.75 % permanent mild deficits. Seizure outcome did not differ from the rest of the group (82.5 % satisfactory seizure control). In contrast, all intraaxial hematomas after tumor surgery (N = 4, incidence 1.9 %) were located in or adjacent to the resection cavity. Prognosis was much worse with parenchymal hemorrhages after tumor surgery: three of four patients died, one survived with a severe hemiparesis, only two patients with extraaxial hematomas (incidence 1 %) had a complete recovery. The 3 % incidence of symptomatic hemorrhages was only insignificantly lower compared to the TLE group, patients with tumor surgery were older than TLE patients (49 versus 33 years), and in five of six patients only incomplete tumor resection was achieved.

CONCLUSION

Although associated with a low permanent morbidity, features of postoperative hemorrhages after TLE surgery are characteristically different to complications after surgery for other indications, which has to be kept in mind for patient counseling and obtaining informed consent.

Does the choice of treatment influence survival of patients with small hepatocellular carcinoma in compensated cirrhosis?

OBJECTIVE

Untreated patients with small, single hepatocellular carcinoma (HCC) in compensated cirrhosis are characterized by a relatively good prognosis.

METHODS

We report the findings generated in a retrospective study on a cohort of 186 consecutive patients with small (< 5 cm) HCC in Child A or B cirrhosis, who were transplanted (four), underwent surgery (15), or were treated with percutaneous ethanol injection (117), lipiodol chemoembolization (44) or best supportive care (six), depending on their clinical features.

RESULTS

Overall survival was 26% at 5 years (31% Child A, 20% Child B), with a mean and median survival of 44 and 38 months, respectively. The longest survival was obtained with transplantation and surgery, and the worst with best supportive care. When untreated patients were not considered, no significant differences were observed between the different types of treatment, however, even when patients in the Child A group were considered alone. Almost all the patients who underwent surgery relapsed. No significant difference was observed in relation to the stage of the disease, while alpha-fetoprotein levels were singled out as the only relevant prognostic factor in a multivariate Cox's regression model. Costs per year of life saved were extremely high for transplantation and lowest for ethanol injection, with surgery being less expensive than chemoembolization.

CONCLUSIONS

This study confirms that patients with single, small HCC nodules in well compensated cirrhosis should be treated. The choice of type of treatment should be based on the availability of local resources and expertise, and on the patients' preference, after they have been properly informed on the survival, morbidity and mortality related to each treatment option. The relative cost of the procedures should also be considered.

Evaluation of inverse methods and head models for EEG source localization using a human skull phantom

We used a real-skull phantom head to investigate the performances of representative methods for EEG source localization when considering various head models. We describe several experiments using a montage with current sources located at multiple positions and orientations inside a human skull filled with a conductive medium. The robustness of selected methods based on distributed source models is evaluated as various solutions to the forward problem (from the sphere to the finite element method) are considered. Experimental results indicate that inverse methods using appropriate cortex-based source models are almost always able to locate the active source with excellent precision, with little or no spurious activity in close or distant regions, even when two sources are simultaneously active. Superior regularization schemes for solving the inverse problem can dramatically help the estimation of sparse and focal active zones, despite significant approximation of the head geometry and the conductivity properties of the head tissues. Realistic head models are necessary, though, to fit the data with a reasonable level of residual variance.

Spatiotemporal profile of synaptic activation produced by the electrical and visual stimulation of retinal inputs to the optic tectum: a current source density analysis in the pigeon (Columba livia)

The optic tectum of the pigeon is a highly organized, multilayered structure that receives a massive polystratified afference of at least five different populations of retinal ganglion cells and gives rise to various anatomically segregated efferent systems. The synaptic organization of retino-tectal circuitry is, at present, mostly unknown. To investigate the spatiotemporal profile of synaptic activation produced by differential (electrical and visual) stimulation of the retinal inputs, we performed a high-spatial-resolution current source density analysis in the optic tectum of the anaesthetized pigeon. Electrical stimuli consisted of brief pulses of different durations applied to the optic nerve head, while visual stimuli consisted of light flashes of different intensities. Electrical stimulation generated sinks confined to retinorecipient layers. The temporal structure, spatial location and thresholds of these sinks indicated that they are all due to primary tectal synapses of retinal fibers with different conduction velocities. Sinks evoked by the fastest retinal axons were more superficially located than sinks produced by slower retinal fibers. Visual stimulation, on the other hand, resulted in a more complex pattern of current sinks, with various sinks located in the retinorecipient layers and also well below. Visual stimulation induced action potentials at superficial as well as deep tectal levels. We conclude that electrical stimulation activates most of the populations of ganglion cells as well as their primary tectal synapses, but is unable to elicit a significant activation of secondary tectal synapses. Visual stimulation, on the contrary, activates just some of the incoming retinal populations, but in a way that produces noticeable secondary activation of intratectal circuits. Laminar segregation of retinally evoked tectal activity, as reported here, has also been found in other vertebrates. Similarities and differences with previous studies are discussed.

Reversible mechanical fixation of eye position in awake head-restrained pigeons (Columba livia)

Here we describe a method to fix gaze positions and to significantly reduce saccadic oscillations in pigeons. The procedure consists of a mechanical immobilization of the eye through the use of an electromagnet that exerts a radial force upon a small metal rectangle glued to the dorsal part of the eye. The method can be used in avian visual neurophysiology in order to hold the eye immobilized for periods of time, long enough to map the properties of visual receptive fields and investigate the possible functions of saccadic oscillations.

Combined MEG and EEG source imaging by minimization of mutual information

Though very frequently assumed, the necessity to operate a joint processing of simultaneous magnetoencephalography (MEG) and electroencephalography (EEG) recordings for functional brain imaging has never been clearly demonstrated. However, the very last generation of MEG instruments allows the simultaneous recording of brain magnetic fields and electrical potentials on the scalp. But the general fear regarding the fusion between MEG and EEG data is that the drawbacks from one modality will systematically spoil the performances of the other one without any consequent improvement. This is the case for instance for the estimation of deeper or radial sources with MEG. In this paper, we propose a method for a cooperative processing of MEG and EEG in a distributed source model. First, the evaluation of the respective performances of each modality for the estimation of every dipole in the source pattern is made using a conditional entropy criterion. Then, the algorithm operates a preprocessing of the MEG and EEG gain matrices which minimizes the mutual information between these two transfer functions, by a selective weighting of the MEG and EEG lead fields. This new combined EEG/MEG modality brings major improvements to the localization of active sources, together with reduced sensitivity to perturbations on data.

Genetic variation and bill size dimorphism in a passerine bird, the reed bunting Emberiza schoeniclus

In passerine birds morphological differentiation in bill size within species is not commonly observed. Bill size is usually associated with a trophic niche, and strong differences in it may reflect the process of genetic differentiation and, possibly, speciation. We used both mitochondrial DNA (mtDNA) and nuclear microsatellites to study genetic variation between two subspecies of reed bunting, Emberiza schoeniclus schoeniclus and E.s. intermedia, along their distributional boundary in western Europe. These two subspecies are characterized by a high dimorphism in bill size and, although breeding populations of the two subspecies are found very close to each other in northern Italy, apparently no interbreeding occurs. The observed morphological pattern between the two subspecies may be maintained by geographically varying selective forces or, alternatively, may be the result of a long geographical separation followed by a secondary contact. MtDNA sequences of cytochrome b and ND5 (515 bp) showed little variation and did not discriminate between the two subspecies, indicating a divergence time of less than 500 000 years. The analysis of four microsatellite loci suggested a clear, although weak, degree of genetic differentiation in the large- and small-billed populations, as indicated by FST and RST values and genetic distances. The correlation between bill size and genetic distance between populations remained significant after accounting for the geographical distances between sampling localities. Altogether, these results indicate a very recent genetic differentiation between the two bill morphs and suggest that a strong selection for large bills in the southern part of the breeding range is probably involved in maintaining the geographical differentiation of this species.

Surgical second look in ovarian cancer: a randomized study in patients with laparoscopic complete remission--a Northeastern Oncology Cooperative Group-Ovarian Cancer Cooperative Group Study

PURPOSE

The usefulness of extensive and repetitive surgery for patients with ovarian cancer still remains unproven (at least for some conditions). We planned an accurate prospective test of the hypothesis that patients with advanced-stage disease, after they had reached a clinical complete remission (CR), may benefit from surgical second look (SSL).

PATIENTS AND METHODS

One hundred two patients in CR (as assessed by clinical findings, markers, and visualization by computed tomographic [CT] scan and laparoscopy), after initial debulking and first-line chemotherapy, were randomized to two arms, which were well balanced for predictive criteria such as age, stage at presentation, histology, grading, date of randomization, and residua after first surgery. Forty-eight patients were randomly assigned to receive follow-up evaluation only, while 54 were assigned to receive second surgery (eight of them refused). Of 46 surgical patients, 35 had negative and 11 positive surgical findings (24% clinically false-negative).

RESULTS

Despite the microscopic residua found at open surgery, and the fact that the patients were then treated with second-line chemotherapy, SSL did not increase the probability of survival in this setting. In an analysis of the results according to the intention-to-treat criteria, after a 60-month follow-up period, the overall survival rates in the two groups of patients (SSL v no SSL) were 65% and 78%, respectively (P = .14). Multivariate analysis according to predictive criteria confirmed there was no significant difference between the two groups (P = .39).

CONCLUSION

Our study shows the following: (1) our second-line treatment is scarcely effective; (2) SSL accurately defines complete responders to first-line chemotherapy; (3) SSL per se does not prolong survival; and (4) if confirmed, a less invasive procedure could replace SSL as a valuable method in new first-line regimens in ovarian cancer patients with clinical CR confirmed by laparoscopy.

Pulmonary valvular stenosis associated with Takayasu's Disease. Favorable response to corticosteroids. A case report

The authors describe the first reported case of type IV Takayasu's arteritis with pulmonary valve stenosis. After thirty months under corticosteroid therapy the disappearance of the pulmonary valve stenosis signs was observed in the patient. In the same patient coarctation of the aorta, aortic insufficiency, stenosis of both pulmonary arteries, and left coronary artery stenosis were observed. This case illustrates the extensive cardiovascular involvement that can occur in Takayasu's arteritis and suggests that pulmonary valvular stenosis could be secondary to the same inflammatory process.

Evaluation of patch testing in patients with chronic vulvar symptoms

The Dermogynaecology Clinic was established at the Mercy Hospital for Women in 1989. Since its inception, 700 patients have been investigated and 15% were clinically diagnosed as having contact dermatitis. Primary irritant dermatitis was regarded as the common cause but to investigate the place of contact allergy 50 patients were patch tested to a standard battery, medicaments, preservatives, corticosteroids and miscellaneous allergens. Twenty-one patients (42%) had a total of 44 positive tests. The most common positive reactions were to nickel (22%), cobalt (6%), fragrances (12%), caine mix (6%) and ethylenediamine (8%). Medicaments and fragrances were regarded as important allergens. Corticosteroid and imidazole allergy was not a problem in this series of patients.