Feasibility, Clinical Potential, and Limitations of Trans-Burr Hole Ultrasound for Postoperative Evaluation of Chronic Subdural Hematoma: A Prospective Pilot Study

BACKGROUND AND OBJECTIVES

Chronic subdural hematoma (CSDH) is commonly managed through burr hole surgery. Routine follow-up using computed tomography (CT) imaging is frequently used at many institutions, contributing to significant radiation exposure. This study evaluates the feasibility, safety, and reliability of trans-burr hole sonography as an alternative postoperative imaging modality, aiming to reduce radiation exposure by decreasing the frequency of CT scans.

METHODS

We conducted a prospective pilot study on 20 patients who underwent burr hole surgery for CSDH. Postoperative imaging included both CT and sonographic examinations through the burr hole. We assessed the ability to measure residual subdural fluid thickness under the burr hole sonographically compared with CT, the occurrence of complications, and the potential factors affecting sonographic image quality. The Pearson correlation coefficient was used to demonstrate relationships between CT and ultrasound and axial and coronal ultrasound.

RESULTS

Sonography through the burr hole was feasible in 73.5% of cases, providing measurements of residual fluid that closely paralleled CT findings, with an average discrepancy of 1.2 mm for axial and 1.4 mm for coronal sonographic views. A strong positive correlation was found between axial and coronal ultrasound (r = 0.955), CT and axial ultrasound (r = 0.936), and CT and coronal ultrasound (r = 0.920). The primary obstacle for sonographic imaging was the presence of air within the burr hole or the subdural space, which typically resolved over time after surgery.

CONCLUSION

Trans-burr hole sonography emerges as a promising technique for postoperative monitoring of CSDH, with the potential to safely reduce reliance on CT scans and associated radiation exposure in selected patients. Our results support further investigation into the extended use of sonography during the follow-up phase. Prospective multicenter studies are recommended to establish the method's efficacy and to explore strategies for minimizing air presence postsurgery.

From molecular signatures to radiomics: tailoring neurooncological strategies through forecasting of glioma growth

OBJECTIVE

Contemporary oncological paradigms for adjuvant treatment of low- and intermediate-grade gliomas are often guided by a limited array of parameters, overlooking the dynamic nature of the disease. The authors' aim was to develop a comprehensive multivariate glioma growth model based on multicentric data, to facilitate more individualized therapeutic strategies.

METHODS

Random slope models with subject-specific random intercepts were fitted to a retrospective cohort of grade II and III gliomas from the database at Kepler University Hospital (n = 191) to predict future mean tumor diameters. Deep learning-based radiomics was used together with a comprehensive clinical dataset and evaluated on an external prospectively collected validation cohort from University Hospital Zurich (n = 9). Prediction quality was assessed via mean squared prediction error.

RESULTS

A mean squared prediction error of 0.58 cm for the external validation cohort was achieved, indicating very good prognostic value. The mean ± SD time to adjuvant therapy was 28.7 ± 43.3 months and 16.1 ± 14.6 months for the training and validation cohort, respectively, with a mean of 6.2 ± 5 and 3.6 ± 0.7, respectively, for number of observations. The observed mean tumor diameter per year was 0.38 cm (95% CI 0.25-0.51) for the training cohort, and 1.02 cm (95% CI 0.78-2.82) for the validation cohort. Glioma of the superior frontal gyrus showed a higher rate of tumor growth than insular glioma. Oligodendroglioma showed less pronounced growth, anaplastic astrocytoma-unlike anaplastic oligodendroglioma-was associated with faster tumor growth. Unlike the impact of extent of resection, isocitrate dehydrogenase (IDH) had negligible influence on tumor growth. Inclusion of radiomics variables significantly enhanced the prediction performance of the random slope model used.

CONCLUSIONS

The authors developed an advanced statistical model to predict tumor volumes both pre- and postoperatively, using comprehensive data prior to the initiation of adjuvant therapy. Using radiomics enhanced the precision of the prediction models. Whereas tumor extent of resection and topology emerged as influential factors in tumor growth, the IDH status did not. This study emphasizes the imperative of advanced computational methods in refining personalized low-grade glioma treatment, advocating a move beyond traditional paradigms.

Global Outcomes for Microsurgical Clipping of Unruptured Intracranial Aneurysms: A Benchmark Analysis of 2245 Cases

BACKGROUND AND OBJECTIVES

Benchmarks represent the best possible outcome and help to improve outcomes for surgical procedures. However, global thresholds mirroring an optimal and reachable outcome for microsurgical clipping of unruptured intracranial aneurysms (UIA) are not available. This study aimed to define standardized outcome benchmarks in patients who underwent clipping of UIA.

METHODS

A total of 2245 microsurgically treated UIA from 15 centers were analyzed. Patients were categorized into low- ("benchmark") and high-risk ("nonbenchmark") patients based on known factors affecting outcome. The benchmark was defined as the 75th percentile of all centers' median scores for a given outcome. Benchmark outcomes included intraoperative (eg, duration of surgery, blood transfusion), postoperative (eg, reoperation, neurological status), and aneurysm-related factors (eg, aneurysm occlusion). Benchmark cutoffs for aneurysms of the anterior communicating/anterior cerebral artery, middle cerebral artery, and posterior communicating artery were determined separately.

RESULTS

Of the 2245 cases, 852 (37.9%) patients formed the benchmark cohort. Most operations were performed for middle cerebral artery aneurysms (53.6%), followed by anterior communicating and anterior cerebral artery aneurysms (25.2%). Based on the results of the benchmark cohort, the following benchmark cutoffs were established: favorable neurological outcome (modified Rankin scale ≤2) ≥95.9%, postoperative complication rate ≤20.7%, length of postoperative stay ≤7.7 days, asymptomatic stroke ≤3.6%, surgical site infection ≤2.7%, cerebral vasospasm ≤2.5%, new motor deficit ≤5.9%, aneurysm closure rate ≥97.1%, and at 1-year follow-up: aneurysm closure rate ≥98.0%. At 24 months, benchmark patients had a better score on the modified Rankin scale than nonbenchmark patients.

CONCLUSION

This study presents internationally applicable benchmarks for clinically relevant outcomes after microsurgical clipping of UIA. These benchmark cutoffs can serve as reference values for other centers, patient registries, and for comparing the benefit of other interventions or novel surgical techniques.

Machine learning based outcome prediction of microsurgically treated unruptured intracranial aneurysms

Machine learning (ML) has revolutionized data processing in recent years. This study presents the results of the first prediction models based on a long-term monocentric data registry of patients with microsurgically treated unruptured intracranial aneurysms (UIAs) using a temporal train-test split. Temporal train-test splits allow to simulate prospective validation, and therefore provide more accurate estimations of a model's predictive quality when applied to future patients. ML models for the prediction of the Glasgow outcome scale, modified Rankin Scale (mRS), and new transient or permanent neurological deficits (output variables) were created from all UIA patients that underwent microsurgery at the Kepler University Hospital Linz (Austria) between 2002 and 2020 (n = 466), based on 18 patient- and 10 aneurysm-specific preoperative parameters (input variables). Train-test splitting was performed with a temporal split for outcome prediction in microsurgical therapy of UIA. Moreover, an external validation was conducted on an independent external data set (n = 256) of the Department of Neurosurgery, University Medical Centre Hamburg-Eppendorf. In total, 722 aneurysms were included in this study. A postoperative mRS > 2 was best predicted by a quadratic discriminant analysis (QDA) estimator in the internal test set, with an area under the receiver operating characteristic curve (ROC-AUC) of 0.87 ± 0.03 and a sensitivity and specificity of 0.83 ± 0.08 and 0.71 ± 0.07, respectively. A Multilayer Perceptron predicted the post- to preoperative mRS difference > 1 with a ROC-AUC of 0.70 ± 0.02 and a sensitivity and specificity of 0.74 ± 0.07 and 0.50 ± 0.04, respectively. The QDA was the best model for predicting a permanent new neurological deficit with a ROC-AUC of 0.71 ± 0.04 and a sensitivity and specificity of 0.65 ± 0.24 and 0.60 ± 0.12, respectively. Furthermore, these models performed significantly better than the classic logistic regression models (p < 0.0001). The present results showed good performance in predicting functional and clinical outcomes after microsurgical therapy of UIAs in the internal data set, especially for the main outcome parameters, mRS and permanent neurological deficit. The external validation showed poor discrimination with ROC-AUC values of 0.61, 0.53 and 0.58 respectively for predicting a postoperative mRS > 2, a pre- and postoperative difference in mRS > 1 point and a GOS < 5. Therefore, generalizability of the models could not be demonstrated in the external validation. A SHapley Additive exPlanations (SHAP) analysis revealed that this is due to the most important features being distributed quite differently in the internal and external data sets. The implementation of newly available data and the merging of larger databases to form more broad-based predictive models is imperative in the future.

A randomized, single ascending dose safety, tolerability and pharmacokinetics study of NicaPlant® in aneurysmal subarachnoid hemorrhage patients undergoing clipping

Introduction

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high morbidity and mortality. Post-hemorrhagic vasospasm with neurological deterioration is a major concern in this context. NicaPlant®, a modified release formulation of the calcium channel blocker nicardipine, has shown vasodilator efficacy preclinically and a similar formulation known as NPRI has shown anti-vasospasm activity in aSAH patients under compassionate use.

Research question

The study aimed to assess pharmacokinetics and pharmacodynamics of NicaPlant® pellets to prevent vasospasm after clip ligation in aSAH.

Material and methods

In this multicenter, controlled, randomized, dose escalation trial we assessed the safety and tolerability of NicaPlant®. aSAH patients treated by clipping were randomized to receive up to 13 NicaPlant® implants, similarly to the dose of NPRIs previous used, or standard of care treatment.

Results

Ten patients across four dose groups were treated with NicaPlant® (3-13 implants) while four patients received standard of care. 45 non-serious and 13 serious adverse events were reported, 4 non-serious adverse events and 5 serious adverse events assessed a probable or possible causal relationship to the investigational medical product. Across the NicaPlant® groups there was 1 case of moderate vasospasm, while in the standard of care group there were 2 cases of severe vasospasm.

Discussion and conclusion

The placement of NicaPlant® during clip ligation of a ruptured cerebral aneurysm raised no safety concern. The dose of 10 NicaPlant® implants was selected for further clinical studies.

Deep learning-assisted radiomics facilitates multimodal prognostication for personalized treatment strategies in low-grade glioma

Determining the optimal course of treatment for low grade glioma (LGG) patients is challenging and frequently reliant on subjective judgment and limited scientific evidence. Our objective was to develop a comprehensive deep learning assisted radiomics model for assessing not only overall survival in LGG, but also the likelihood of future malignancy and glioma growth velocity. Thus, we retrospectively included 349 LGG patients to develop a prediction model using clinical, anatomical, and preoperative MRI data. Before performing radiomics analysis, a U2-model for glioma segmentation was utilized to prevent bias, yielding a mean whole tumor Dice score of 0.837. Overall survival and time to malignancy were estimated using Cox proportional hazard models. In a postoperative model, we derived a C-index of 0.82 (CI 0.79-0.86) for the training cohort over 10 years and 0.74 (Cl 0.64-0.84) for the test cohort. Preoperative models showed a C-index of 0.77 (Cl 0.73-0.82) for training and 0.67 (Cl 0.57-0.80) test sets. Our findings suggest that we can reliably predict the survival of a heterogeneous population of glioma patients in both preoperative and postoperative scenarios. Further, we demonstrate the utility of radiomics in predicting biological tumor activity, such as the time to malignancy and the LGG growth rate.

Cortical and Subcortical Anatomy of the Orbitofrontal Cortex: A White Matter Microfiberdissection Study and Case Series

BACKGROUND

The literature on white matter anatomy underlying the human orbitofrontal cortex (OFC) is scarce in spite of its relevance for glioma surgery.

OBJECTIVE

To describe the anatomy of the OFC and of the underlying white matter fiber anatomy, with a particular focus on the surgical structures relevant for a safe and efficient orbitofrontal glioma resection. Based on anatomical and radiological data, the secondary objective was to describe the growth pattern of OFC gliomas.

METHODS

The study was performed on 10 brain specimens prepared according to Klingler's protocol and dissected using the fiber microdissection technique modified according to U.T., under the microscope at high magnification.

RESULTS

A detailed stratigraphy of the OFC was performed, from the cortex up to the frontal horn of the lateral ventricle. The interposed neural structures are described together with relevant neighboring topographic areas and nuclei. Combining anatomical and radiological data, it appears that the anatomical boundaries delimiting and guiding the macroscopical growth of OFC gliomas are as follows: the corpus callosum superiorly, the external capsule laterally, the basal forebrain and lentiform nucleus posteriorly, and the gyrus rectus medially. Thus, OFC gliomas seem to grow ventriculopetally, avoiding the laterally located neocortex.

CONCLUSION

The findings in our study supplement available anatomical knowledge of the OFC, providing reliable landmarks for a precise topographical diagnosis of OFC lesions and for perioperative orientation. The relationships between deep anatomic structures and glioma formations described in this study are relevant for surgery in this highly interconnected area.

The influence of smoking in minimally invasive spinal fusion surgery

Background

The impact of smoking on spinal surgery has been studied extensively, but few investigations have focused on minimally invasive surgery (MIS) of the spine and the difference between complication rates in smokers and non-smokers. We evaluated whether a history of at least one pack-year preoperatively could be used to predict adverse peri- and postoperative outcomes in patients undergoing minimally invasive fusion procedures of the lumbar spine. In a prospective study, we assessed the clinical effectiveness of MIS in an unselected population of 187 patients.

Methods

We evaluated perioperative and postoperative complication rates in MIS fusion techniques of the lumbar spine in smoking and non-smoking patients. MIS fusion was performed using interbody fusion procedures and/or posterolateral fusion alone.

Results

Smokers were significantly younger than non-smokers. We did not encounter infection at the site of surgery or severe wound healing disorder in smokers. We registered no difference between the smoking and non-smoking groups with regard to peri- or postoperative complication rate, blood loss, or length of stay in hospital. We found a significant influence of smoking (p = 0.049) on the overall perioperative complication rate.

Conclusion

MIS fusion techniques seem to be a suitable tool for treating degenerative spinal disorders in smokers.

Bowel perforation after ventriculoperitoneal-shunt placement: case report and review of the literature

Bowel perforation by a peritoneal catheter (BPPC) is a serious complication after ventriculoperitoneal shunting, with high mortality and morbidity rates. This patient presented with scalp ulceration over the shunt valve at the retromastoid region 26 years after shunt placement. During revision, the catheter distal to the valve was divided in the clavicular region. As there was no cerebrospinal fluid drainage, we decided to remove the ventricular catheter and valve. The ulceration was debrided and primarily closed. Distal to the clavicle, the disconnected peritoneal catheter was encased in a fibrous, calcified tunnel. To avoid piecemeal resection with multiple incisions, the catheter was not retrieved. Two years later, the patient presented with an abscess and pus draining from the clavicular wound. Cultures were positive for enteric bacteria. BPPC with retrograde spread of infection was suspected, and abdominal computed tomography confirmed perforation. We removed the disconnected catheter, but the perforation site could not be detected during laparotomy. The patient was treated with intravenous antibiotics and recovered without complications. To minimize complications, abandoned catheters should be avoided. Otherwise, patients unnecessarily have a life-long risk of developing abdominal complications. In patients with abandoned catheters and severe abdominal symptoms, BPPC is an important differential diagnosis.

The influence of age on the peri- and postoperative clinical course in patients undergoing minimally invasive transforaminal lumbar interbody fusion techniques of the lumbar spine

OBJECTIVE

As a result of continuously increasing life expectancy, the number of requests for surgery to treat degenerative diseases of the spine in the elderly population will increase. Since older age is associated with the occurrence of medical comorbidities, the demand for less extensive surgical approaches is growing. The aim of this study is to establish whether minimally invasive fusion techniques are a safe and adequate tool for use in elderly patients.

PATIENTS AND METHODS

We analyzed 187 patients who underwent minimally invasive surgery (MIS) in the form of one- to four-level fusion procedures. In 146 patients, additional widening of the spinal canal was performed. The subjects were grouped into four age categories of approximately equal size (33-56, 56-66, 66-74 and 74-85). The effect of age on the incidence of peri- and postoperative complications was investigated and compared between the age groups.

RESULTS

Older age was not associated with the occurrence of perioperative complications, which include wound healing disorders, hematomas, wound traction-blisters and cerebrospinal fluid leakage. Fourteen patients (7.49%) encountered distinct surgical technique related complications, making surgical revision necessary in eight patients (4.28%). Furthermore, increasing age didn't elevate the risk of postoperative adverse events, i.e. pulmonary embolism, ischemic heart attack or pneumonia, among others. However, older patients were found to stay in hospital longer than younger patients, especially when more than one level was fused.

CONCLUSIONS

Minimally invasive surgery techniques are safe in elderly patients. The small-scale surgical approach guarantees a low incidence of infections and wound healing disorders. However, a longer hospital stay must be expected in older patients.

Surgical and Clinical Results of Minimally Invasive Spinal Fusion Surgery in an Unselected Patient Cohort of a Spinal Care Unit

OBJECTIVES

To review the surgical results and to identify possible parameters influencing the clinical outcomes in an unselected patient collective undergoing minimally invasive lumbar interbody fusion in a spinal care unit.

METHODS

A total of 229 adult patients who underwent minimally invasive lumbar spinal fusion between 2008 and 2016 were included in this retrospective analysis. Lumbar fusion was performed using transforaminal interbody fusion (TLIF) devices and posterolateral fusion. To eliminate confounding parameters, in all patients interbody fusion was indicated by lumbar degenerative pathologies, and surgery was performed using the same fusion device. Treatment efficacy was evaluated using scores describing pain (visual analogue scale [VAS]) and health impairment (EQ-5D, Oswestry Disability Index [ODI]). The influence of patient age, obesity, active smoking status, and co-morbidities on clinical outcome and perioperative complications was analyzed.

RESULTS

The patient population reviewed had improved VAS (P_{(leg pain)} ≤ 0.0001, P_{(back pain)} ≤ 0.0001), ODI (P ≤ 0.0001), EQ-VAS (P ≤ 0.0001), and EQ-5D subscales "mobility", "self-care", "pain", and "anxiety" (P_(mobility) ≤ 0.0001, P_(self-care)  = 0.41, P_(pain) ≤ 0.0001, P_(anxiety)  = 0.011) postoperatively. Neither advanced patient age, nor increased body mass index (BMI), hypertension, or active smoking status had a significantly limiting influence on the success of minimally invasive spinal surgeries (MIS). Duration of surgery strongly correlated with the number of spinal levels treated and with intraoperative blood loss (r = 0.774, P ≤ 0.0001, n = 208). Weak positive correlations were found between patient age and duration of surgery (r = 0.184, P = 0.005, n = 229), intraoperative blood loss (r = 0.165, P = 0.012, n = 229), and duration of hospitalization (r = 0.270, P ≤ 0.0001, n = 228), respectively. When compared to non-smokers, smokers were younger (P ≤ 0.0001), and had a significantly lower BMI (P = 0.001), shorter durations of surgery (P ≤ 0.0001), decreased intraoperative blood loss (P = 0.022), and shorter hospital stays (P = 0.006), respectively. Complications occurred in 17 patients (7%) and were not affected by patient age, BMI, hypertension, or active smoking status.

CONCLUSION

Minimally invasive spinal surgery is a safe and effective treatment option and may be superior to open surgery in subpopulations with significant co-morbidities and risk factors, such as elderly and obese patients as well as patients with an active smoking status.

The impact of type 2 diabetes on the peri- and postoperative outcomes of minimally invasive fusion techniques in the lumbar spine

BACKGROUND

The impact of diabetes on spinal surgery has been studied extensively, but very few studies have focused on minimal access spinal technologies (MAST) and complication rates in patients suffering from type 2 diabetes (T2DM). Diabetes increases the risk of wound healing disorders, complication rate and length of stay in the hospital. We focused on the peri- and postoperative complications of MAST in an unselected consecutive population of 187 patients suffering from degenerative disorders lumbar spine disorders. Since mostly older patients are affected by degenerative lumbar changes, we concentrated on T2DM.

METHODS

We evaluated perioperative and postoperative complication rates associated with MAST fusion techniques in lumbar spine surgery in patients suffering from T2DM compared to patients without diabetes. Lumbar fusion was performed using interbody and posterolateral fusion.

RESULTS

Eighteen female and sixteen male patients suffered from T2DM (15.65% and 22.22% respectively). No differences between patients with and without T2DM concerning surgery-related complications including infections, severe wound healing disorders or length of in-hospital stay were noted. Peri- or postoperative complication rates, as well as blood loss volumes, were evenly distributed between the two groups.

CONCLUSIONS

T2DM is not a risk factor for the occurrence of complications in MAST.

Abdominal Pseudocysts and Peritoneal Catheter Revisions: Surgical Long-Term Results in Pediatric Hydrocephalus

OBJECTIVE

An abdominal pseudocyst (APC) is a distal catheter site-specific failure in patients treated with ventriculoperitoneal shunts. Few studies with more than 10 patients have been reported. The aim of this study was to analyze causes of peritoneal catheter revisions with special emphasis on revisions because of an APC.

METHODS

Pediatric patients with first shunt operation between 1982 and 1992 were included, and time, cause, and modality of peritoneal catheter revision were determined retrospectively.

RESULTS

One hundred thirty-eight patients were treated for hydrocephalus, and 112 patients received a peritoneal catheter during the follow-up. An APC was diagnosed in 14 (12.5%) patients, and 28 revisions were needed for its treatment. The rate of shunt infection in patients with APC was 50%, but bacterial examination of the pseudofluid culture revealed infection in only 3 patients. Age at first surgical procedure, type of first surgical procedure, and etiology of hydrocephalus were not associated with APC diagnosis. APC recurred in 4 patients. These patients had a catheter repositioning directly into the peritoneum as first surgical treatment. No recurrences were observed in patients with shunt externalization or replacement of the peritoneal catheter.

CONCLUSIONS

An APC is a major long-term complication after ventriculoperitoneal shunt treatment. Although a sterile inflammatory response cannot be excluded completely, our results favor the hypothesis of low-level shunt infection. In both cases, the surgical consequences are the same. An infected APC should be treated as a shunt infection. Uninfected patients can be treated with shunt externalization and replacement of only the peritoneal catheter.

Demography, maternal health and the epidemiology of malaria and other major infectious diseases in the rural department Tsamba-Magotsi, Ngounie Province, in central African Gabon

BACKGROUND

Sub-Saharan Africa is undergoing an epidemiological transition from a predominance of infectious diseases to non-communicable and lifestyle related conditions. However, the pace of this transition and the pattern of disease epidemiology are uneven between affluent urban and rural poor populations. To address this question for a remote rural region located in the central African rainforest region of Gabon, this study was conducted to assess reasons for health care attendance and to characterize the epidemiology of malaria and other major infectious diseases for the department of Tsamba Magotsi.

METHODS

Major causes for health care attendance were collected from local hospital records. Cross sectional population based surveys were performed for the assessment of local malaria epidemiology. Pregnant women attending antenatal care services were surveyed as a sentinel population for the characterization of chronic viral and parasitic infections in the community.

RESULTS

Infectious diseases were responsible for 71% (7469) of a total of 10,580 consultations at the formal health care sector in 2010. Overall, malaria - defined by clinical syndrome - remained the most frequent cause for health care attendance. A cross sectional malaria survey in 840 asymptomatic individuals residing in Tsamba Magotsi resulted in a Plasmodium spp. infection prevalence of 37%. The infection rate in 2-10 year old asymptomatic children - a standard measure for malaria endemicity - was 46% (100 of 217) with P. falciparum as predominant species (79%). Infection with other plasmodial species (P. ovale and P. malariae) presented most commonly as coinfections (23.2%). Prevalence of HIV, HBV, and syphilis were 6.2, 7.3, and 2.5%, respectively, in cross-sectional assessments of antenatal care visits of pregnant women. Urogenital schistosomiasis and the filarial pathogens Loa loa and Mansonella perstans are highly prevalent chronic parasitic infections affecting the local population.

CONCLUSIONS

Despite major improvements in the accessibility of Tsamba Magotsi over the past decade the epidemiological transition does not appear to have majorly changed on the spectrum of diseases in this rural Gabonese population. The high prevalence of Plasmodium infection indicates a high burden of malaria related morbidity. Infectious diseases remain one of the most important health issues and further research activities in the field of tropical medicine and infectious diseases could help improve health care for the local population.

Long-term mortality rates in pediatric hydrocephalus-a retrospective single-center study

PURPOSE

Very long-term follow-up and outcome are rare for pediatric patients with hydrocephalus and shunt operations. The aim of this study was to determine the long-term mortality rates in these patients.

METHODS

Pediatric patients with first shunt operation between 1982 and 1992 were included. For each patient, time and cause of death were determined. Further, patients with first operation from 1982 to 1987 were compared to those first operated from 1988 to 1992.

RESULTS

One-hundred thirty-seven patients were included. Etiologies of hydrocephalus were intraventricular hemorrhage (31.4 %), meningomyelocele (25.5 %), postinfectious (11.7 %), congenital (10.2 %), posterior fossa cyst (8.8 %), aqueductal stenosis (8 %), and others (4.4 %). Overall, 53 patients (38.7 %) died. The percentage of patients surviving 1, 2, 10, and 20 years after first operation were 82.6, 73.6, 69.4, and 65.3 %, respectively. In 23 patients, the cause of death was related to shunt treatment: shunt infection was diagnosed in 18 and acute shunt dysfunction in 5 patients. Mortality was considerably higher for patients with their first operation in time period 1982-1987 compared to time period 1988-1992 (51 versus 25 %). The reduction of mortality was mainly due to an increased survival after shunt infection. Eighty-seven patients survived more than 20 years after initial shunt operation. Of those long-term survivors, three (3.4 %) patients died 22-24 years after first operation.

CONCLUSION

Mortality in hydrocephalic pediatric patients is high especially in the first postoperative years but is even significant in adult patients with pediatric hydrocephalus. As deaths occur even after 20 years, routine follow-up of long-term survivors remains necessary.

Diagnostic limitations in the treatment of cerebral aneurysms

BACKGROUND

Endovascular coiling has become a standard technique in the treatment of cerebral aneurysms. The mechanisms of recurrence are incompletely understood.

METHODS

In our clinical investigations we present three uncommon cases where the pathology at the base might has been underestimated in digital subtraction or magnetic resonance angiography.

RESULTS

In the first clinical study rehemorrhage occurred 11 years after endovascular coiling. Before rehemorrhage occurred, serial magnetic resonance angiographies had revealed a stable situation with only a small base remnant after initial endovascular treatment. In the second clinical study, intraprocedural rupture during endovascular coiling occurred and a residual angiographic occult lesion was detected only during microsurgical clipping. In the third clinical study, we again found a residual lesion during microsurgical clipping.

CONCLUSION

We present three clinical studies were the pathology at the base might has been underestimated in digital subtraction angiography or magnetic resonance angiography. The incidence of angiographic occult residuals is unknown, but their clinical relevance may be important. Beside other mechanisms, these lesions might be the source of aneurysmal regrowth and hemorrhage (Fig. 4, Ref. 27).

Effects of azithromycin and tanomastat on experimental bronchiolitis obliterans

OBJECTIVE

Azithromycin has become a standard of care in therapy of bronchiolitis obliterans following lung transplantation. Matrix metalloprotease-9 broncho-alveolar lavage levels increase in airway neutrophilia and bronchiolitis obliterans. Interleukin-17 may play a role in lung allograft rejection, and interleukin-12 is downregulated in bronchiolitis obliterans. Whether these mechanisms can be targeted by azithromycin remains unclear.

METHODS

Bronchiolitis obliterans was induced by transplantation of Fischer F344 rat left lungs to Wistar Kyoto rats. Allografts with azithromycin therapy from day 1 to 28 or 56 and mono- or combination therapy with the broad-spectrum matrix metalloprotease inhibitor tanomastat from day 1 to 56 were compared to control allografts and isografts. Graft histology was assessed, and tissue cytokine expression studied using Western blotting and immunofluorescence.

RESULTS

The chronic airway rejection score in the azithromycin group did not change between 4 and 8 weeks after transplantation, whereas it significantly worsened in control allografts (P = .041). Azithromycin+tanomastat prevented complete allograft fibrosis, which occurred in 40% of control allografts. Azithromycin reduced interleukin-17 expression (P = .049) and the number of IL-17(+)/CD8(+) lymphocytes at 4 weeks, and active matrix metalloprotease-9 at 8 weeks (P = .017), and increased interleukin-12 expression (P = .025) at 8 weeks following transplantation versus control allografts.

CONCLUSIONS

The expression of interleukin-17 and matrix metalloprotease-9 in bronchiolitis obliterans may be attenuated by azithromycin, and the decrease in interleukin-12 expression was prevented by azithromycin. Combination of azithromycin with a matrix metalloprotease inhibitor is worth studying further because it prevented complete allograft fibrosis in this study.

Glioblastoma with the appearance of arteriovenous malformation: pitfalls in diagnosis

OBJECTIVES

Very few cases of arteriovenous malformations (AVMs) associated with gliomas were reported so far in the literature.

METHODS

Here, we report a rare case of a glioblastoma with an AVM-like lesion and review the existing literature.

RESULTS

We report an unusual case of a 72-year old woman, who presented with a progressive history of aphasia, memory deficit, and headache. Initial MRI imaging was suggestive of a high-grade glioma for which a pterional craniotomy was performed. Intraoperatively, the lesion resembled a vascular malformation. Total extirpation of the lesion was verified by intraoperative MR imaging. Initial histopathological analysis revealed an AVM. Due to the discrepancy between the radiologic and histopathologic findings, the patient was monitored at close intervals. Two month later, multiple lesions were visible on MRI imaging, thus, supporting the diagnosis of malignant glioma. Therefore, after reinvestigating the histopathological sections and cutting the paraffin block in additional serial sections, in only 5% of the section a glioblastoma was discerned which was surrounded by an AVM-like lesion.

CONCLUSION

Gliomas are rarely found in association with AVMs and require accurate diagnostic evaluation and interpretation for adequate therapeutic interventions.

Serum glutathione S-transferase P1 1 in prediction of cardiac function

Background

Glutathione S-transferase P1 1 (GSTP1) belongs to the multigene isozyme family involved in cellular response to oxidative stress and apoptosis. Our initial retrospective proteomic analysis suggested that GSTP1 is associated with heart failure (HF). Although pro–B-type natriuretic peptide (proBNP) serves currently as a surrogate diagnostic and prognostic parameter in HF patients, its specificity remains uncertain. We hypothesized that GSTP1 might be a useful serum marker in the monitoring of HF patients.

Methods and Results

Serum GSTP1 and proBNP were prospectively measured in 193 patients subdivided based on their ejection fraction (EF) either in equal-sized quintiles or predefined EF groups >52%, 43%–52%, 33%–42%, 23%–32% and ≤22%. At a cutoff of ≥231 ng/mL, GSTP1 identified HF patients with EF ≤22% with 81% sensitivity and 83% specificity, and at a cutoff of ≥655 pg/mL, proBNP identified the same patient group with 84% sensitivity and 22% specificity. GSTP1 at a ≥126 ng/mL cutoff identified EF ≤42% with 90% sensitivity and 95% specificity, or proBNP at a ≥396 pg/mL cutoff had 97% sensitivity and 20% specificity. In regression analyses, GSTP1, but not proBNP, discriminated between EF ≤42% and EF >42% in HF patients.

Conclusions

These results suggest that GSTP1 is strongly associated with HF and could serve as a sensitive and specific marker to predict the ventricular function in HF patients.

Improvement of cardiac function in the failing rat heart after transfer of skeletal myoblasts engineered to overexpress placental growth factor

BACKGROUND

Transplant of skeletal myoblasts is an attractive alternative to repair irreversibly damaged myocardium in ischemic heart failure. We investigated whether transplant of myoblasts overexpressing placental growth factor would stimulate angiogenesis and enhance myoblast survival in a rat heart failure model.

METHODS

Three weeks after myocardial infarction, Sprague-Dawley rats in heart failure received intramyocardial injections of Ringer solution (control) or autologous myoblasts, unmodified or transfected with placental growth factor expression plasmid. Sham-operated animals served as noninfarct controls. Cardiac function was assessed by echocardiography to 86 days after engraftment. Immunocytochemistry and fluorescence imaging were used to investigate vessel formation, grafted myoblast survival, infarct wall thickness, and infarct size. Quantitative real-time reverse transcriptase polymerase chain reaction and Western blotting measured tissue messenger RNA and protein expressions.

RESULTS

Left ventricular function significantly improved with time, and fractional shortening on day 86 was significantly enhanced in transfected myoblast group relative to control (P < .01) and unmodified myoblast (P < .05) groups. Vascular density (P < .01) and myoblast survival (P < .05) were enhanced in rats treated with transfected myoblasts relative to other groups (P < .05). Mean fraction of fibrotic scar tissue was decreased in unmodified and transfected myoblast groups relative to controls on day 86 (P < .05), and left ventricular wall thickness was significantly increased in transfected myoblast group relative to other groups (P < .05).

CONCLUSIONS

Intramyocardial injections of autologous myoblasts overexpressing placental growth factor improved cardiac function, attenuated adverse cardiac remodeling, induced angiogenesis, and probably enhanced survival of grafted myoblasts.

Persistent plasminogen activator inhibitor 1 gene expression in cardiac transplant recipients with idiopathic dilated cardiomyopathy

OBJECTIVES

Plasminogen activator inhibitor 1 is the primary regulator of urokinase plasminogen activator and tissue plasminogen activator. Plasminogen activator inhibitor 1 is essential in the control of the thrombotic/fibrinolytic balance and is a marker of endothelial cell injury. Idiopathic dilated cardiomyopathy is reportedly associated with endothelial cell dysfunction. Whether endothelial cell damage plays a role in patients with dilated cardiomyopathy after cardiac transplantation remains unknown.

METHODS

In this study explanted hearts of cardiac transplant recipients with ischemic cardiomyopathy and dilated cardiomyopathy, as well as control myocardial tissue, were investigated for expression of urokinase plasminogen activator, tissue plasminogen activator, urokinase plasminogen activator receptor, and plasminogen activator inhibitor 1 and 2. Furthermore, plasminogen activator inhibitor 1 expression was examined in endomyocardial biopsy specimens and sera of patients with ischemic cardiomyopathy and those with dilated cardiomyopathy during the first posttransplantation year. The effect of the patient's serum on endothelial cells was assessed in vitro to examine the role of circulating endothelial cell damage-related factors.

RESULTS

Plasminogen activator inhibitor 1 expression was upregulated in ischemic cardiomyopathy and dilated cardiomyopathy myocardial tissue versus that seen in control tissue. After transplantation, plasminogen activator inhibitor 1 expression returned to control levels in patients with ischemic cardiomyopathy. In patients with dilated cardiomyopathy, plasminogen activator inhibitor 1 expression increased at 24 weeks after transplantation in both biopsy specimens and sera versus that seen in control tissue. Sera of patients with dilated cardiomyopathy, but not that of patients with ischemic cardiomyopathy, inhibited vascular endothelial growth factor A-induced proliferation of endothelial cells, although downstream target gene activation of early growth response factor 1 and NGFI-A binding protein 2 was not affected.

CONCLUSIONS

These data suggest for the first time that the endothelial cell damage-related process recurs in patients with dilated cardiomyopathy after transplantation, which, independently of vascular endothelial growth factor, is associated with increased plasminogen activator inhibitor 1 expression, and that this pathology might play a role in allograft remodeling in patients with dilated cardiomyopathy.

Serum matrix metalloprotease-1 and vascular endothelial growth factor--a predict cardiac allograft rejection

Cardiac allograft rejection is currently diagnosed from endomyocardial biopsies (EMB) that are invasive and impractical to repeat. A serological marker could facilitate rejection monitoring and minimize EMB-associated risks. We investigated the relation of serum matrix metalloprotease (MMP)-1 and vascular endothelial growth factor (VEGF)-A concentrations to cardiac allograft rejection, using 1176 EMBs and serum samples obtained from 208 recipients. Acute cellular rejection was diagnosed in 186 EMBs. Mean week 1 and week 2 serum MMP-1 concentrations predicted rejection (p = 0.001, AUC = 0.80). At the optimal cut-off level of >or=7.5 ng/mL, MMP-1 predicted rejection with 82% sensitivity and 72% specificity. Initial serum MMP-1 <5.3 ng/mL (lowest quartile) was associated with rejection-free outcome in 80% of patients. Both MMP-1 (p < 0.001, AUC = 0.67-0.75) and VEGF-A (p < 0.01, AUC = 0.62-0.67) predicted rejection on the next EMB, while rejection at EMB was identified only by VEGF-A (p < 0.02, AUC = 0.70-0.77). Patients receiving combined cyclosporine-A and everolimus had the lowest serum MMP-1 concentrations. While serum MMP-1 predicts rejection-free outcome and VEGF-A identifies rejection on EMB, both markers predict rejection in follow-up of cardiac transplant recipients. Combination of serum MMP-1 and VEGF-A concentration may be a noninvasive prognostic marker of cardiac allograft rejection, and could have important implications for choice of surveillance and immunosuppression protocols.

Management of complications in surgery of the colon

BACKGROUND

General surgeons are frequently confronted with colorectal diseases in their daily practice, whereby colorectal cancer is the second most common malignant tumour, with almost 5000 new cases every year in Austria. The incidence of benign colon disorders requiring surgery (e.g. colon polyps, sigmoid diverticulitis) is also increasing. The first aim in colon surgery should be to avoid complications and if they occur to treat them properly.

METHODS

We basically distinguish between general and special complications. As general complications, prevention of malnutrition and support of the immune system should receive special attention. As the number of elderly patients increases, so does the risk not only of thrombembolic complications but also of critical cardiocirculatory situations, and renal and hepatic failure. Special complications depend either on the type of surgery (laparoscopic assisted, conventional open surgery) or the techniques employed (stapled, hand sutured). Handling of the tissue also plays a major role (e.g. dry versus wet pads).

RESULTS

Shortening of the postoperative stay decreases both hospital costs and the incidence of infections, meaning that minimally invasive surgery and postoperative "fast track nutrition" should be promoted. Emergency operations should be avoided (e.g. bridging through colonic stents), as morbidity and mortality are clearly increased in comparison to (semi-) elective operations. During the operation itself, new equipment and techniques (such as Ultracision®, Ligasure®) as well as a well coordinated team help to reduce complications and duration of surgery.

CONCLUSIONS

To avoid is better than to repair. If complications do occur, appropriate surgical and intensive - care measures should be taken immediately.

Influence of a synbiotic mixture consisting of Lactobacillus acidophilus 74-2 and a fructooligosaccharide preparation on the microbial ecology sustained in a simulation of the human intestinal microbial ecosystem (SHIME reactor)

Lactobacillus acidophilus 74-2, which is used in probiotic products, was administered, with fructo-oligosaccharide in a milk-based product, to the second vessel (duodenum/jejunum) of the SHIME reactor, an in vitro simulation of the human intestinal microbial ecology. The main focus of this study was to monitor the changes of the population density of selected bacterial species in the intestine and the changes of metabolic activities during the supplementation of L. acidophilus and fructooligosaccharide in the SHIME reactor. Interestingly, the addition of L. acidophilus 74-2 with fructooligosaccharide gave rise to an increase of bifidobacteria. Moreover, major positive changes occurred in the production of volatile fatty acids: a strong upward trend was observed especially in the case of butyric acid and propionic acid. Furthermore a noticeable increase of beta-galactosidase activity was monitored, while the activity of beta-glucuronidase, generally considered undesirable, declined.