The influence of hepatitis B and hepatitis C virus infection in the recipient on late renal allograft failure

BACKGROUND

Chronic liver disease is one of the most important complications after renal transplantation. Hepatitis B and mainly hepatitis C are the more frequent causes of liver disease. Although there are controversial results, in some series, hepatitis B and hepatitis C are associated with lower graft and patient survival.

PATIENTS AND METHODS

A total of 3365 adult patients who received a renal transplant in 1990 (N = 824), 1994 (N = 1075) and 1998 (N = 1466) with a functioning graft after the first year were included. Fifty-one (2.1%) with positive HbsAg were diagnosed with hepatitis B at transplantation; 488 (16.9%) presented positive anti-hepatitis C antibodies and were diagnosed with hepatitis C virus (HCV) infection and 25 patients (0.8%) were diagnosed with concomitant hepatitis B virus (HBV) and HVC infection. Demographic, immunosuppression, survival figures and post-transplant and follow-up data of these patients and negative HBV and HVC patients were recorded.

RESULTS

The overall prevalence of HBV in the recipients was 2.1%. Patient survival was lower and liver disease was the main cause of death in HBV-positive patients. However, in the multivariate analysis the presence of positive HbsAg did not have an independent risk factor for graft loss and patient death. This finding was similar in patients with concomitant HBV and HVC infection. Graft and patient survival were lower in HCV-positive patients and liver disease was the main cause of death. Interestingly, proteinuria and serum creatinine were risk factors for graft loss and patient death. Fortunately, prevalence of HCV in the recipients significantly decreased from 29% in 1990 to 10% in 1998.

CONCLUSIONS

In the last decade in Spain, HBV infection in the recipients, showing an overall prevalence approximately 2%, did not influence graft and patient survival. However, HCV infection in the recipient was associated with lower graft and patient survival, although the prevalence of HCV clearly decreased from 29% in 1990 to 10% in 1998.

Sirolimus-Based Therapy With or Without Cyclosporine: Long-Term Follow-up in Renal Transplant Patients

This open-label, phase 3b, extension trial in renal transplant recipients (Sirolimus Study 311) assessed the long-term safety of sirolimus (SRL) administered with cyclosporine (CsA) (SRL + CsA group, n = 98) or without CsA (SRL group, n = 69). Renal transplant recipients who had either completed one of seven previous SRL studies sponsored by Wyeth Research or had participated for > or =3 months and reached a protocol-designated endpoint were eligible for enrollment. Data were available for 167 patients, all of whom initially received steroids. Mean total SRL exposure was 1526 days, including previous study participation. After enrollment in the extension study, there were significantly more acute rejections in the SRL + CsA group (6.1% vs 0%, P < .05). Differences in rates of graft loss (3.1% vs 1.4%) and death (6.1% vs 1.4%) were not significantly different between SRL + CsA and SRL groups, respectively. At 48 months after transplantation, calculated GFR (53.4 vs 70.9 mL/min) and hemoglobin (124.9 vs 136.6 g/L) were significantly better in the SRL group. Lipid values were not significantly different between groups at 48 months. The incidence of treatment-emergent increased creatinine, anemia, hypertension, headache, epistaxis, abnormal kidney function, and upper respiratory infection were significantly higher in the SRL + CsA group, whereas no adverse events were significantly higher in the SRL group. Malignancies were reported more frequently (11.2% vs 0%) with SRL + CsA. Results from this extension study indicate that SRL-based therapy without CsA is a safe alternative to combination therapy with CsA, offering long-term improvement in renal function with no increased risk of late acute rejection.

Hepatitis C virus infection and renal disease after renal transplantation

Hepatitis C virus (HCV) infection is the main cause of chronic liver disease after renal transplantation (RT). It is considered in some series to be a risk factor for graft loss and patient death. Also, HCV has been implicated in the pathogenesis of glomerular diseases in native and transplanted kidneys. The presence of membranoproliferative (MP) or membranous (M) glomerulonephritis (GN) in HCV-positive patients has been well documented after RT, but there is no clear data concerning the real prevalence of HCV-induced glomerulonephritis. MPGN with or without cryoglobulinemia and MGN have been described in HCV RNA-positive patients in general without severe liver disease. Also, there is a possible association between HCV infection and acute/chronic transplant glomerulopathy. Renal thrombotic microangiopathy has been described in HCV-positive patients with positive anti-cardolipin antibodies. The pathogenesis of MPGN and MGN in HCV patients after RT seems to be similar to that which occurs in native kidneys: the deposition of immune complexes containing HCV proteins in the glomeruli. Renal biopsy, using light microscopy, immunofluorescence techniques, and electron microscopy, is useful to achieve a correct diagnosis. Unfortunately, interferon is not recommended due to the significant risk of rejection. The possibility of pegylated interferon needs to be tested. Ribavirin can improve proteinuria but HCV RNA remains positive. Finally, recent data suggest that the use of interferon in HCV patients on dialysis can negate HCV RNA and prevent associated glomerulonephritis after RT.

Chronic cyclosporine-induced nephrotoxiciy in heart transplant patients: Long-term benefits of treatment with mycophenolate mofetil and low-dose cyclosporine

BACKGROUND

Cyclosporine-induced nephropathy is a major limitation in heart transplant patients. Cyclosporine dose reduction may lead to substantial early improvement in renal function. Our aim was to study the long-term benefits of therapy with low doses of cyclosporine plus mycophenolate mofetil in heart transplant patients with drug-induced nephrotoxicity.

METHODS

Twenty-five adult heart transplant patients with cyclosporine-related nephrotoxicity (mean posttransplant = 41.7 +/- 25.7 months) were included in the retrospective analysis (22 men, mean age = 58.8 +/- 7.9 years.). Patients were switched from azathioprine to mycophenolate mofetil (1 to 3 g/d), followed by a stepwise reduction in cyclosporine dosage (trough cyclosporine level maintained around 100 ng/mL). Renal function was determined by serial measurements of serum creatinine and glomerular filtration rate at 3-month intervals.

RESULTS

With a mean follow-up of 30 +/- 13 months, the baseline creatinine of 2.37 +/- 0.5 mg/dL decreased to 1.59 +/- 0.40 mg/dL (P < .0001). The baseline glomerular filtration rate of 36.77 +/- 10.10 mL/min improved to 54.98 +/- 13.80 mL/min (P < .0001). The cyclosporine level was the unique independent variable associated with renal functional improvement (partial R(2) = 0.4). Within the first 3 months, renal function displayed a rapid improvement after conversion to mycophenolate mofetil (P < .001), reaching a plateau, without further significant improvement over the course of time.

CONCLUSIONS

Cyclosporine-induced nephrotoxicity is not a progressive, irreversible disease. Reduction in cyclosporine exposure by addition of mycophenolate mofetil is useful to achieve long-term renal functional improvement, thereby avoiding chronic renal failure. A unique, significant factor associated with this improvement was the reduction in cyclosporine level.

Methods and demographic findings of the baseline survey of the NEDICES cohort: a door-to-door survey of neurological disorders in three communities from Central Spain

OBJECTIVE

To describe the methods and general results of the baseline longitudinal survey in a defined cohort of elderly people from three areas of Central Spain (urban and rural). The survey was designed to study dementia, essential tremor, Parkinson's disease and stroke.

STUDY DESIGN

A population-based longitudinal study with door-to-door interviews.

METHODS

This study was carried out in two phases: Phase 1 (health status questionnaire and screening performed by lay interviewers) and Phase 2 (diagnosis of neurological illnesses by neurologists).

RESULTS

The study flow chart, screening instruments for neurological disorders, main demographic data (age, sex, educational attainment, occupation) and general health status of the 5,278 screened participants (2,238 men and 3,040 women) are given for the two phases. The response rate was 85.3%, and participation was higher in men and in the urban area.

CONCLUSIONS

Participation rates were good in both phases of the NEDICES baseline study, and this was influenced by age, sex and setting of the participants. Educational attainment, occupation and health status data are analogous to other Spanish studies performed in the elderly. As the study population was large and good participation rates were achieved, precise analysis of morbidity of the neurological disorders investigated will be possible.

[Subthalamic nucleus targeting and spatial variability]

AIM

The effectiveness of anatomic localization of the subthalamic nucleus (EAL) was assessed and the mapping method is described here. The symmetry of contralateral nuclei (SCN) was analyzed on 11 parkinsonian patients submitted to bilateral subthalamotomy with ablative lesioning.

PATIENTS AND METHODS

To assess EAL the percentage so much of first trajectory (p1) as the total of trajectories (pt) that hit the target and the rest of subthalamic nucleus average distance (d) was calculated. The anatomic localization error (epsilon) is determined as a difference between first trajectory coordinates with those of medial determined nucleus point, through electrophysiological data as to the statistical significance of this error. SCN is analyzed by contrasting equality hypothesis at the nucleus maximum height alongside a trajectory, average electrophysiological position center and spatial distribution of all intranuclear recordings found in each hemisphere in all patients.

RESULTS

The pi, pt and d obtained values were 86.36%, 86.13% and 1.41 +/- 1.01 mm respectively. The epsilon value was greater in anteroposterior direction of 1.11 +/- 0.83 mm without statistical significance. The average number of recorded trajectories for the first procedure was 6.45 and 6 for the second. The asymmetry of contralateral nucleus was not significant.

CONCLUSIONS

An indirect method with CT brain images and a new electrophysiological mapping method with a multiunitary recording for first and second nucleus is safe enough and it yields a high effectiveness in anatomofunctional nucleus localization. The nucleus of a same patient are symmetrical. There is little space variability among patient non related to the differences in the intercommissural distance.

Results of kidney transplantation in recipients over 70 years of age: experience at a single center

We performed 41 kidney transplants in patients >70 years (35 single and 6 dual), with a mean recipient age of 72+/-2 years, from January 1990 to December 2001. Mean age of the donors was 69+/-12 years. Immunosuppression used triple therapy with steroids, mycophenolate mofetil, and cyclosporine or tacrolimus. Cold ischemia time was 23+/-3 hours. The incidence of primary nonfunction was 4.8%, and delayed graft function 58.5%. Acute rejection incidence was 12%. The actuarial patient survival rates at 12, 24, and 36 months were 82.5%, 82.5%, and 75%, respectively. Actuarial survival rates of the grafts censuring for death of the recipient with a functioning graft were 89.5%, 86%, and 68%, respectively. Nine of the 18 graft losses were due to recipient death. Overall, renal transplant recipients >70 years showed good results. The principal cause of graft loss was recipient death.

Early elimination of cyclosporine in kidney transplant recipients receiving sirolimus prevents progression of chronic pathologic allograft lesions

Cyclosporine elimination in a regimen including sirolimus has been shown to be a safe and effective approach to improve graft function. Nevertheless, it is still unknown whether the functional benefit of CyA withdrawal coincides with a subsequent reduction in histologic lesions of chronic damage or development of chronic allograft nephropathy. This consideration would forecast a reduction in the rate of long-term graft loss. We analyzed 114 graft biopsies from a subgroup of 57 patients that had been included in a randomized study to eliminate CyA at 3 months posttransplant from a regimen including sirolimus either in group A CyA + SRL vs group B of SRL with CyA elimination at 3 months. Every patient had two biopsies, one at transplantation and another at 1 year. The biopsy reading was performed in a blinded manner by a central pathologist using the Banff 1997 and the CADI classifications. A significantly lower rate of progression of tubular and interstitial chronic lesions between basal and 1-year biopsies was observed for group B patients. In addition, the incidence of new cases of chronic allograft nephropathy during the first year was significantly lower in the group in which CyA had been eliminated at 3 months posttransplant. We conclude that early elimination of CyA in the first months posttransplant, when SRL is used as the main immunosuppressant, reduces the appearance or worsening of chronic histologic lesions, probably as a consequence of long-term CyA toxicity prevention.

Helical computed tomography angiography is the most efficient test to assess vascular calcifications in the iliac arterial sector in renal transplant candidates

The increased scope of renal transplant indications has lead to a larger number of recipients with vascular problems due to arterial calcifications in the iliac region. Compared to magnetic resonance and conventional arteriography, helical computed tomography angiography (HCTA) accurately depicts arterial diseases, including the location and extent of arterial calcification. The objective of this study was to assess the value of HCTA with maximum-intensity-projection (MIP) reconstruction to evaluate iliac arterial calcifications and stenosis among candidates for renal transplantation.

MATERIAL AND METHODS

From December 1997 to March 2002, 114 HCTA scans with MIP reconstruction were performed in candidates for renal transplantation. Included patients fulfilled some of the following conditions: (a) older than 55 years, (b) diabetic, (c) second transplants, and (d) obvious vascular calcifications on plain abdominal x-ray.

RESULTS

Among the 114 patients, 33 (29%) were excluded for transplantation due to universal calcification of the iliac arterial sector, and 81 (71%) were included on the waiting list due to the presence of calcium-free areas for the vascular anastomosis. Transplantation, which was attempted in 28 of the 81 patients, was successful in 25 using the area programmed after HCTA analysis. The transplants failed in three cases because no calcium-free area could be found upon surgical examination.

CONCLUSION

HCTA with MIP reconstruction makes it possible to draw an exact map of the arterial calcifications of the iliac arterial sector, allowing better recipient selection and accurate planning for the vascular anastomosis and placement of the renal graft.

Obesity favors surgical and infectious complications after renal transplantation

The prevalence of obesity is increasing in the renal transplant population. There are controversial data with respect to posttransplant outcome. We performed a study comparing the incidence of surgical and infectious complications among 40 obese patients (body mass index [BMI] pretransplant > or =30 kg/m2) versus a matched nonobese control group (BMI <30 kg/m2) transplanted at our center between June 1989 and March 2001.

RESULTS

There were no differences in patient demographic variables (mean age, gender, cause of renal failure, or percentage of diabetes or hepatitis C virus infection). Donor age, HLA mismatching, sensitization, cold ischemia time, and immunosuppressive regimen were similar in both groups. The mean pretransplant BMI in obese and nonobese patients was 34.1+/-4.0 versus 23.00+/-2.73 kg/m2 (P<.01). The obese group showed a higher incidence of delayed graft function (30% versus 5%, P<.05) and wound infections (12.5%) posttransplant with similar incidences of wound dehiscence, perigraft collections, and graft function at the end of follow up.

Health-related quality of life and its relationship to cognitive and emotional functioning in multiple sclerosis patients

The existing knowledge about the health-related quality of life (HRQoL) and its relationship to cognitive and/or emotional functioning in multiple sclerosis (MS) is scarce. We assessed differences between subgroups of MS outpatients (n = 209) on one HRQoL instrument: a version of the Functional Assessment of Multiple Sclerosis quality of life instrument; on two cognitive functioning tests: the Mini-Mental State Examination and the clock drawing test; and on two emotional functioning tests: the Hamilton Rating Scale for Depression and the Hamilton Rating Scale for Anxiety. Three disease-related characteristics were assessed: physical disability, duration of the illness, and clinical course. The results showed that each of these has an effect on at least one dimension of HRQoL and on one mental functioning test. Thus, the more severe, the more progressive, and the longer the illness duration, the lower the HRQoL. Likewise, cognitive mean scores decreased and emotional mean scores increased with greater illness severity and progressive the MS. Furthermore, we also found significant correlations between cognitive and emotional functioning tests and HRQoL dimensions. Thus, the worse cognitive functioning and the higher depressive and anxiety symptoms score the lower the HRQoL.

[Database application for information on post-surgical evolution after functional neurosurgery]

INTRODUCTION

A series of quantitative scales have been established internationally to evaluate the functional state of patients affected by movement disorders, such as Parkinson s disease. The values of these parameters offered by each patient, measured at different moments during his or her illness, allow us to conduct studies into their evolution as well as perform statistical studies about the casuistics. AIM. To provide a tool that enables us to study this vast amount of material in an efficient, sure and, above all, automated manner. Materials and methods. We selected the most interesting variables from the international protocols. We also designed and developed a database application for use under the Windows environment using Delphi 3.0 language and compiler and Structured Query Language.

RESULTS

We designed, developed and validated a database system so as to be able to handle automatically the information on the clinical evolution of patients who had undergone functional neurosurgery. This system not only enables us to collect all relevant pre and post surgical information but also allows fast searches and selection, data processing using descriptive statistical techniques and the exportation of the data in a standard format. The system, which also allows final double blind clinical evaluation of each patient to be performed, has been used successfully in the Movement Disorders Clinic at the CIREN for over three years.

CONCLUSIONS

This system allows for a considerable saving in the amount of time and effort needed for the post surgical evolution of patients, while also increasing the reliability of the results obtained.

Sirolimus steady-state trough concentrations are not affected by bolus methylprednisolone therapy in renal allograft recipients

AIMS

To determine whether bolus doses of methylprednisolone affect the steady-state trough concentrations of sirolimus.

METHODS

Fourteen renal transplant recipients received concentration-controlled sirolimus therapy in combination with azathioprine and steroids (n=8) or mycophenolate mofetil and steroids (n=6). Bolus doses of methylprednisolone (mean total dose over 1-5 days, 1694 mg; range, 500-3000 mg) were given for the treatment of acute rejection. For each patient, the sirolimus dose (mean, 24.1 mg; range, 3.3-52.5 mg) was the same before and during methylprednisolone therapy.

RESULTS

Mean sirolimus whole blood trough concentrations before and after treatment with methylprednisolone were 28.8 ng ml-1 (range, 13.9-45.3 ng ml-1), and 28.5 ng ml-1 (range, 13.0-47.9 ng ml-1), respectively (P=0.85; 95% confidence interval on the difference -3.3, 4.0 ng ml-1).

CONCLUSIONS

Bolus methylprednisolone treatment does not affect steady-state sirolimus trough concentrations.

Personal-computer-based system for three-dimensional anatomic-physiological correlations during stereotactic and functional neurosurgery

This paper describes the automatic three-dimensional (3D) graphic possibilities that are supplied by the Neurosurgical Deep Recording System (NDRS) to facilitate anatomic-physiological targeting during stereotactic and functional neurosurgery using depth recording. This software has been developed to substitute the complex electronic equipment ordinarily used for deep brain electrical recording, display and processing by a personal computer. It may also help to improve on-line graphic analysis, automatic management of the recorded information and flexibility to implement different forms of signal analysis. It can automatically show a 2D or 3D representation of the electrode track, with the electrophysiological findings superimposed as well as the corresponding sagittal, coronal and axial views of a brain atlas using automatic scaling. The NDRS has already successfully been applied during more than 300 neurosurgeries in Spain and Cuba, enabling improved targeting accuracy and safety.

Efficacy of a selective and differential medium for isolating Corynebacterium urealyticum from urine specimens

OBJECTIVE: To describe a new selective and differential medium for improving the isolation of Corynebacterium urealyticum from urine. METHODS: A total of 370 urine specimens, 270 from patients with underlying urologic disease and 100 from to a control group without renal pathology, were cultured on standard sheep blood agar medium and on a new selective medium for Corynebacterium urealyticum. RESULTS: The use of this selective medium resulted in a nine-fold increase in the prevalence of bacteriuria caused by C. urealyticum (12.4% versus 1.4%). Furthermore, the frequency of patients with symptomatic bacteriuria detected with the selective medium (3.2%) was higher than with the non-selective medium (1.4%). CONCLUSIONS: We recommend the use of this selective medium for the isolation of C. urealyticum in patients with underlying urologic disease or with chronic urinary symptoms.

[Direct approach to carotid cavernosa fistula type of arterio venous dural malformation. Case report and review of the literature]

OBJECTIVES

Barrow's D type carotid cavernosa fistula (FCC) with progressive symptoms and in whom endovascular procedures have failed meet criteria for a direct approach. We report a case of this type of vascular lesion in whom partial endovascular embolization was done together with a direct approach to the FCC, using a method of localization involving a transoperative imaging guide. Digital subtraction angiography and Estereoflex stereotactic system was used.

PATIENTS AND METHODS

A female patient had had a previous minor head injury. She had a progressive neurological disorder with marked visual defect, and had been diagnosed on angiography as having FCC with afferents from branches of the internal carotid artery (ACI) and external carotid artery (ACE). After failure of endovascular treatment orbito zygomatic craniotomy was done with extra intradural dissection and exposure of the antero lateral triangle of the cavernous sinus (SC). The fistula was closed completely by anterior packing with the venous component. Transoperative stereotactic angiographic checks were done to localize and control the packing.

CONCLUSIONS

The Barrow's type D FCC in which embolization treatment has failed may be treated using a direct approach to the anterolateral triangle of the SC. The AC1 remained permeable, fistula was occluded and there was minimal morbidity.

Problems and issues with door-to-door, two-phase surveys: an illustration from central Spain

In 1994-1995, a screening and examination survey was conducted to ascertain the prevalence of dementia, Parkinson's disease and stroke in two urban communities and one rural community of central Spain. We use this survey to illustrate many nonclinical aspects of conducting two-phase prevalence surveys. Special emphasis is given to two common weaknesses in such surveys: screening nonparticipation and screening validation.

Fibrosing cholestatic hepatitis-like syndrome in hepatitis B virus-negative and hepatitis C virus-negative renal transplant recipients

Cholestatic hepatitis and diffuse liver fibrosis have been described in immunosuppressed patients with hepatitis B virus or hepatitis C virus infection as fibrosing cholestatic hepatitis (FCH). FCH is characterized by cholestasis, with only a modest increase in aminotransferase levels. The pathologic picture typically shows periportal and perisinusoidal fibrosis, scarce mixed infiltrates, hepatocellular ballooning, and histologic cholestasis. We report two patients with diffuse fibrosis and cholestasis quite similar to the histologic picture of FCH, but in whom neither hepatitis B virus nor hepatitis C virus infection could be shown, highlighting the potential contribution of cytomegalovirus infection and azathioprine toxicity in the development of this severe complication of solid-organ transplantation.

Influence of cyclosporin, tacrolimus and rapamycin on renal function and arterial hypertension after renal transplantation

Cyclosporin and tacrolimus have improved survival figures in organ transplantation. However, both drugs are potentially nephrotoxic. The immunosuppressive and nephrotoxic effects of both drugs appear to depend on the inhibition of calcineurin. Cyclosporin and tacrolimus cause acute (functional changes) and chronic nephrotoxicity (structural lesions in the kidney). These last important lesions include arteriolar hyalinosis, stripped interstitial fibrosis and tubular atrophy. It is possible that repeated episodes of renal ischaemia contribute to the development of chronic nephrotoxicity and then chronic allograft nephropathy. Cyclosporin and tacrolimus also induce arterial hypertension. Therefore, the beneficial effects of immunosuppression have been limited due to nephrotoxicity and arterial hypertension. Rapamycin, a novel immunosuppressive agent, that does not inhibit calcineurin, provides immunosuppression without nephrotoxicity. In fact, in the trials performed in Europe, sirolimus-treated immunosuppression patients exhibited a much better renal function than cyclosporin-treated patients. However, sirolimus can potentiate the nephrotoxic effect of cyclosporin. Therefore, when cyclosporin and sirolimus are used in combination, a reduction of the cyclosporin dose is desirable.

Dose optimization of mycophenolate mofetil when administered with a low dose of tacrolimus in cadaveric renal transplant recipients

BACKGROUND

Supplementation of immunosuppressive therapy with mycophenolate mofetil (MMF) has been found to reduce the rate of acute rejection in renal transplantation. We report a dose-finding study for MMF when administered in combination with low-dose tacrolimus and corticosteroid prophylaxis in cadaveric renal transplant recipients.

METHODS

Two hundred thirty-two patients at 16 centers were enrolled in this randomized, parallel-group study. The three treatment groups were tacrolimus and corticosteroids (MMF-0 group, n=82); tacrolimus, corticosteroids, and 1 g of MMF daily (MMF-1 g group, n=79); and tacrolimus, corticosteroids, and 2 g of MMF daily (MMF-2 g group, n=71). Study duration was 6 months, and patients were followed up for patient and graft survival for 12 months.

RESULTS

At 6 months posttransplantation, daily doses of 1 g and 2 g of MMF were associated with significantly lower rates of acute rejection compared with tacrolimus alone. The Kaplan-Meier rates were 48.5%, 24.9%, and 22.9%, respectively, for the three treatment groups when acute rejection was determined by clinical criteria (P=0.007). At month 12, patient survival rates were 100%, 97.5%, and 97.2% and graft survival rates were 90.2%, 92.4%, and 93.0% for the MMF-0 group, MMF-1 g group, and the MMF-2 g group, respectively. Gastrointestinal adverse events and leukopenia were higher in the MMF groups, especially in the MMF-2 g group (P<0.05).

CONCLUSIONS

Low-dose tacrolimus combined with a MMF dose of 1 g daily and corticosteroids provided an optimized efficacy and safety profile. A higher dose of MMF (2 g) was associated with greater toxicity without a significant improvement in efficacy.

[An automatic system for anatomophysiological correlation in three planes simultaneously during functional neurosurgery]

INTRODUCTION

The Neurosurgical Deep Recording System (NDRS) using a personal computer takes the place of complex electronic equipment for recording and processing deep cerebral electrical activity, as a guide in stereotaxic functional neurosurgery. It also permits increased possibilities of presenting information in direct graphic form with automatic management and sufficient flexibility to implement different analyses.

OBJECTIVE

This paper describes the possibilities of automatic simultaneous graphic representation in three almost orthogonal planes, available with the new 5.1 version of NDRS so as to facilitate the analysis of anatomophysiological correlation in the localization of deep structures of the brain during minimal access surgery.

MATERIAL AND METHODS

This new version can automatically show the spatial behaviour of signals registered throughout the path of the electrode inside the brain, superimposed simultaneously on sagittal, coronal and axial sections of an anatomical atlas of the brain, after adjusting the scale automatically according to the dimensions of the brain of each individual patient. This may also be shown in a tridimensional representation of the different planes themselves intercepting.

RESULTS

The NDRS system has been successfully used in Spain and Cuba in over 300 functional neurosurgery operations. The new version further facilitates analysis of spatial anatomophysiological correlation for the localization of brain structures.

CONCLUSION

This system has contributed to increase the precision and safety in selecting surgical targets in the control of Parkinson s disease and other disorders of movement.

[Stereotaxic biopsy and 192Ir implant in intracranial tumors. A review of 7 years of experience]

INTRODUCTION

The combination of stereotaxic techniques, advances in neuroimaging and the creation of continually improving software has permitted stereotaxic biopsy of cerebral lesions at the most varied sites. Improvement in the method of permanent interstitial radiation (brachytherapy) improves the precision with which the radioactive sources may be inserted, releasing a maximum dose of radiation to the tumour with minimum radiation to the surrounding tissue.

PATIENTS AND METHODS

We treated 237 patients (aged 1 to 78 years) with intracranial lesions, all included in the protocol of our centre. Stereotaxic systems of Leksell, Riechert-Mundinger, Micromar and Estereoflex were used. The procedure was in three stages: acquisition of the image, surgical planning and surgical operation. The imaging guide was the computerized axial tomography (CAT).

RESULTS

Stereotaxic biopsy guided by CAT images was done in 153 patients. These were divided into three groups, taking the biopsy findings as the reference: group A (primary tumors, 128), group B (metastatic tumors, 15) and group C (non-malignant lesions, 10). Ninety six permanent implants of 192Ir were inserted, with a low dose of 4-7 cGy/h and a total dose of 80-120 Gy.

CONCLUSIONS

Stereotaxic biopsy is a very effective procedure with a significantly low range of complications. The permanent implant with a low dose rate, well situated and using a source of 192Ir is a safe, simple, effective method for the treatment of primary and recurrent glial tumours, and non-glial tumours which fulfil criteria for this type of brachytherapy.

[Stereotaxic microsurgical resection of intracranial tumors guided by imaging and assisted by computer]

INTRODUCTION

The microsurgical techniques for resection of intracranial lesions are limited where anatomical references do not exist or cannot be used as guides in the dissection of deeply located lesions or in more superficial eloquent areas. The stereotaxic guide, guided by imaging gives precise volumetric and geometric definition in intracranial lesions. Its application in the resection of intracranial tumors has special characteristics due to their biological condition and varied localization.

OBJECTIVES

Spatial orientation during surgery is essential. We show this application of stereotaxic surgery in the Centro Internacional de Restauración Neurológica (CIREN) in La Havana, Cuba, between May 1994 and February 1988, describing 65 microsurgical operations done using stereotaxis in 62 patients with intracranial cerebral tumors.

PATIENTS AND METHODS

The procedure was divided into three stages: acquiring an image, computerized axial tomography and surgical planning, with the STASSIS planning system and microsurgical procedures, including systems of stereotaxis: Leksell, Micromar and Estereoflex.

RESULTS

Of the total, 27 of these patients had glial tumors, 33 non-glial tumors and only 2 had non-neoplastic lesions of different sites and sizes. A total of 30 resections were done. Surgical morbidity was minimal and there was no surgical mortality.

CONCLUSIONS

The main advantages of this method are: exact localization of the site for craniotomy, easy spatial orientation and ease in distinguishing the delimitation between the tumour and the healthy tissue. It has been shown that Estereoflex may be used in cerebral microsurgery.

Left atrial aneurysm

Aneurysms of the left atrium are rare abnormalities. They can be congenital or acquired. Whereas a true congenital aneurysm presents as isolated pathology, inflammatory or degenerative processes involving the endocardium are associated with the acquired type. The clinical records of 2 patients with the diagnosis of left atrial aneurysm were reviewed, along with the surgical strategies, current literature, and patient outcomes. Because of the risk of life-threatening complications, surgery is recommended even in asymptomatic cases. Resection and mitral valvuloplasty should be the treatment of choice.

Solid-phase extraction and liquid chromatographic quantitation of quinfamide in biological samples

This paper describes a high-performance liquid chromatographic method for the assay of quinfamide and its main metabolite, 1-(dichloroacetyl)-1,2,3,4,-tetrahydro-6-quinolinol, in plasma, urine and feces. It requires 1 ml of biological fluid, an extraction using Sep-Pack cartridges and acetonitrile for drug elution. Analysis was performed on a CN column (5 microm) using water-acetonitrile-methanol (40:50:10) as a mobile phase at 269 nm. Results showed that the assay was linear in the range between 0.08 and 2.0 microg/ml. The limit of quantitation was 0.08 microg/ml. Maximum assay coefficient of variation was 14%. Recovery obtained in plasma, urine and feces ranged from 82% to 98%.

Ectopia cordis and other midline defects

BACKGROUND

Thoracic ectopia cordis and other midline defects are rare congenital anomalies that often occur with other intracardiac defects. Despite significant improvements in neonatal and infant cardiac surgeries, operations for thoracoabdominal ectopia cordis carry an extremely high mortality with only a few reported survivors of thoracic ectopia cordis.

METHODS

The clinical charts of 4 patients with ectopia cordis over a 6-year period were reviewed. Three of the patients showed varying degrees of Cantrell's Pentalogy; thoracic ectopia cordis was found in 1. We have reviewed our surgical strategies and reported the patients' clinical outcomes.

RESULTS

All 4 patients are alive at follow-up. Two infants with double-outlet right ventricle have been fully corrected, and extracorporeal membrane oxygenation was necessary in 1 infant for cardiac failure following the cardiac repair. A newborn with thoracoabdominal ectopia cordis underwent primary repair of his diaphragmatic defect, and a silo was used to progressively reduce the omphalocele. He is currently awaiting elective repair of tetralogy of Fallot. Lastly, the patient with thoracic ectopia cordis underwent successful soft tissue coverage, and she is being followed in the clinic with restrictive muscular ventricular septal defects and a left ventricular diverticulum.

CONCLUSIONS

Our experience along with other reports in the literature demonstrates that patients with thoracic and thoracoabdominal ectopia cordis can undergo and survive full cardiac, neurologic, and abdominal repair during infancy. Furthermore we advocate different approaches determined by the severity of the presentation and the presence of other complicating factors.