Treatment of post-thalamic hemorrhage hydrocephalus: ventriculoperitoneal shunt or endoscopic third ventriculostomy? A retrospective observational study.

BACKGROUND: The aim of this study was to compare the efficacy of ventriculoperitoneal shunt (VPS) and endoscopic third ventriculostomy (ETV) for the treatment of hydrocephalus after thalamic hemorrhage (TH) where external ventricular drainage (EVD) could not be removed after hematoma absorption, and to provide a theoretical basis for the clinical treatment of hydrocephalus after TH. METHODS: The clinical data of patients with hydrocephalus after TH whose EVD could not be removed after hematoma absorption were retrospectively analyzed. According to the patients' surgical methods, the patients were divided into the VPS group and ETV group. The operative time, length of hospital stay, complications, and reoperation rates of the two groups were compared. RESULTS: There was no statistically significant difference in intraoperative bleeding, length of hospital stay between the two groups. The EVD tubes were successfully removed in all patients after surgery. There were 4 (9.5%) complications in the ETV group and 3 (6.7%) complications in the VPS group, with no statistically significant difference in postoperative complications between the two groups. During the 1-year follow-up, 7 patients (16.7%) in the ETV group and 3 patients (6.7%) in the VPS group required reoperation. In the subgroup analysis of TH combined with fourth ventricular hemorrhage, 6 patients (14.3%) in the ETV group and 1 patient (2.2%) in the VPS group required reoperation, and the difference between the two groups was statistically significant. CONCLUSIONS: ETV had good efficacy in treating hydrocephalus caused by TH and TH that broke into the lateral ventricle and the third ventricle. However, if hydrocephalus was caused by TH with the fourth ventricular hematoma, VPS was a better surgical method because the recurrence rate of hydrocephalus in ETV was higher than that in VPS. Therefore, the choice of surgical method should be based on the patient's clinical features and hematoma location.

Artificial Intelligence for Prediction of Shunt Response in Idiopathic Normal Pressure Hydrocephalus: A Systematic Review.

BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a reversible cause of dementia, typically treated with shunt surgery, although outcomes vary. Artificial intelligence (AI) advancements could improve predictions of shunt response (SR) by analyzing extensive data sets. METHODS: We conducted a systematic review to assess AI's effectiveness in predicting SR in iNPH. Studies using AI or machine learning (ML) algorithms for SR prediction were identified through searches in MEDLINE, EMBASE, and Web of Science up to September 2023, adhering to Synthesis Without Meta-Analysis reporting guidelines. RESULTS: Out of 3541 studies identified, 33 were assessed for eligibility, and 8 involving 479 patients were included. Study sample sizes varied from 28 to 132 patients. Common data inputs included imaging/radiomics (62.5%) and demographics (37.5%), with Support Vector Machine being the most frequently used ML algorithm (87.5%). Two studies compared multiple algorithms. Only four studies reported the Area Under the Curve (AUC) values, which ranged between 0.80 and 0.94. The results highlighted inconsistency in outcome measures, data heterogeneity, and potential biases in the models used. CONCLUSIONS: While AI shows promise for improving iNPH management, there is a need for standardized data and extensive validation of AI models to enhance their clinical utility. Future research should aim to develop robust and generalizable AI models for more effective diagnosis and management of iNPH.

ECG Abnormalities, Diastolic Blood Pressure, and Adverse Events After Systemic to Pulmonary Artery Shunt in Infants with Congenital Heart Disease.

All patients with Systemic to Pulmonary Artery (SPA) shunt as the index surgical procedure at a single center were studied to determine the association between post-operative ECG repolarization abnormalities, diastolic blood pressure (DBP), and adverse outcomes. Postoperative ECGs were categorized into three grades, Grade 2 defined as ST elevation/depression ≥ 2 mm in ≥ 2 precordial or ≥ 1 mm in ≥ 2 limb leads; Grade 1-T-wave inversion or flattening in ≥ 3 leads; and Grade 0-no criteria for grades 1 or 2. For each patient, time with invasive DBP below 25, 25-29, 30-34, or above 34 mmHg in the first 24 h was calculated. The primary outcome was a pre-discharge composite of death, cardiac arrest, ECMO, unplanned shunt reintervention, and necrotizing enterocolitis after 24 h of surgery. Of the 109 patients included in final analysis, 17 (15.6%) had the composite outcome. Grade 2 ECG abnormality occurred in 12%, and Grade 1 in 37%. There was no association between ECG abnormalities and adverse events. Increasing time with DBP < 30 was not associated with adverse outcomes, while increasing time with DBP 30-34 was associated with decreased odds, and increasing time with DBP > 34 mmHg was associated with increased odds of adverse outcomes on multivariable analysis accounting for indexed shunt size and chromosomal abnormalities. In conclusion, after SPA shunt placement, ECG repolarization abnormalities and low DBP within 24 h were common and not associated with adverse outcomes. Sustained elevation of DBP above 34 mmHg was not protective, especially in patients with high indexed shunt size and chromosomal abnormalities.

Computed tomographic features of segmental aplasia of the caudal vena cava, portocaval shunt and Situs ambiguous in two dogs.

A 3-year-old crossbreed dog (case 1) and a 3-month-old German Shorthaired Pointer (case 2) were presented for acute signs of encephalopathy. A portosystemic shunt (PSS) was suspected based on clinical context and laboratory exam results and was confirmed on computed tomography (CT) angiography in both cases. A left-sided azygos (case 1) and right-sided azygos (case 2) continuation of an interrupted caudal vena cava (CVC) and a situs ambiguous (SA) were also observed and considered as incidental findings. Both dogs underwent PSS surgical correction. Postsurgical follow-up imaging procedures suggested concomitant primary hypoplasia of the portal vein (PHPV) in both cases.

Heterologous expression and purification of glutamate decarboxylase-1 from the model plant Arabidopsis thaliana: characterization of the enzyme's in vitro truncation by thiol endopeptidase activity.

Plant glutamate decarboxylase (GAD) is a Ca2+-calmodulin (CaM) activated enzyme that produces γ-aminobutyrate (GABA) as the first committed step of the GABA shunt. Our prior research established that in vivo phosphorylation of AtGAD1 (AT5G17330) occurs at multiple N-terminal serine residues following Pi resupply to Pi-starved cell cultures of the model plant Arabidopsis thaliana. The aim of the current investigation was to purify recombinant AtGAD1 (rAtGAD1) following its expression in Escherichia coli to facilitate studies of the impact of phosphorylation on its kinetic properties. However, in vitro proteolytic truncation of an approximate 5 kDa polypeptide from the C-terminus of 59 kDa rAtGAD1 subunits occurred during purification. Immunoblotting demonstrated that most protease inhibitors or cocktails that we tested were ineffective in suppressing this partial rAtGAD1 proteolysis. Although the thiol modifiers N-ethylmaleimide or 2,2-dipyridyl disulfide negated rAtGAD1 proteolysis, they also abolished its GAD activity. This indicates that an essential -SH group is needed for catalysis, and that rAtGAD1 is susceptible to partial degradation either by an E. coli cysteine endopeptidase, or possibly via autoproteolytic activity. The inclusion of exogenous Ca2+/CaM facilitated the purification of non-proteolyzed rAtGAD1 to a specific activity of 27 (µmol GABA produced/mg) at optimal pH 5.8, while exhibiting an approximate 3-fold activation by Ca2+/CaM at pH 7.3. By contrast, the purified partially proteolyzed rAtGAD1 was >40% less active at both pH values, and only activated 2-fold by Ca2+/CaM at pH 7.3. These results emphasize the need to diagnose and prevent partial proteolysis before conducting kinetic studies of purified regulatory enzymes.

Case report: CSF hypotension secondary to a free syringo-subarachnoid-peritoneal shunt.

INTRODUCTION: Syringomyelia is present in 40% of pediatric patients with Chiari malformation. Typically treated with posterior fossa decompression, some cases require further intervention such as syrinx shunting. CASE REPORT: We report a 16-year-old female with Chiari type 1 malformation and syringomyelia who underwent posterior fossa decompression and subsequent free syringo-subarachnoid-peritoneal shunting. The patient developed symptoms of CSF overdrainage, and imaging indicated CSF hypotension. A distal catheter ligation temporarily improved symptoms, but eventually, a programmable ventricular shunt was necessary due to shunt dependence. CONCLUSION: This case highlights the rare complication of CSF overdrainage from syrinx shunting and the importance of shunt selection considerations.

Superb microvascular ultrasound is a promising non-invasive diagnostic tool to assess a ventriculoperitoneal shunt system function: a feasibility study.

The objective of this pilot study was to assess the reliability of superb microvascular ultrasound (SMI) for the measurement of the cerebrospinal fluid (CSF) flow within VPS systems as an indirect sign for shunt dysfunction. Asymptomatic hydrocephalus patients, with a VPS system implanted between 2017 and 2021, were prospectively enrolled in the study. Using SMI, the CSF flow within the proximal and distal catheters were analysed. Before and after pumping the shunt reservoir, intraabdominal free fluid, optical nerve sheath diameter (ONSD), and papilla diameter (PD) were evaluated and correlated with the amount of valve activation. Nineteen patients were included. A flow was detectable in 100% (N = 19) patients in the proximal and in 89.5% (N = 17) in the distal catheter. The distal catheter tip was detectable in 27.7% (N = 5) patients. Free intraabdominal fluid was initially detected in 21.4% (N = 4) patients and in 57.9% (N = 11) at the end of the examination (P = 0.049). ONSD was significantly lower after pump activation (4.4 ± 0.9 mm versus 4.1 ± 0.8 mm, P = 0.049). Both peak velocity and flow volume per second were higher in proximal compared to distal catheters (32.2 ± 45.2 versus 5.6 ± 3.7 cm/sec, P = 0.015; 16.6 ± 9.5 ml/sec versus 5.1 ± 4.0 ml/sec, P = 0.001, respectively). No correlation was found between the number of pump activations and the changes in ONSD (P = 0.975) or PD (P = 0.820). SMI appears to be a very promising non-invasive diagnostic tool to assess CSF flow within the VPS systems and therefore affirm their function. Furthermore, appearance of free intraperitoneal fluid followed by repeated compression of a shunt reservoir indicates an intact functioning shunt system.

NMDA Receptors and Indices of Energy Metabolism in Erythrocytes: Missing Link to the Assessment of Efficiency of Oxygen Transport in Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that develops in patients with severe liver dysfunction and/or portocaval shunting. Despite more than a century of research into the relationship between liver damage and development of encephalopathy, pathogenetic mechanisms of hepatic encephalopathy have not yet been fully elucidated. It is generally recognized, however, that the main trigger of neurologic complications in hepatic encephalopathy is the neurotoxin ammonia/ammonium, concentration of which in the blood increases to toxic levels (hyperammonemia), when detoxification function of the liver is impaired. Freely penetrating into brain cells and affecting NMDA-receptor-mediated signaling, ammonia triggers a pathological cascade leading to the sharp inhibition of aerobic glucose metabolism, oxidative stress, brain hypoperfusion, nerve cell damage, and formation of neurological deficits. Brain hypoperfusion, in turn, could be due to the impaired oxygen transport function of erythrocytes, because of the disturbed energy metabolism that occurs in the membranes and inside erythrocytes and controls affinity of hemoglobin for oxygen, which determines the degree of oxygenation of blood and tissues. In our recent study, this causal relationship was confirmed and novel ammonium-induced pro-oxidant effect mediated by excessive activation of NMDA receptors leading to impaired oxygen transport function of erythrocytes was revealed. For a more complete evaluation of "erythrocytic" factors that diminish brain oxygenation and lead to encephalopathy, in this study, activity of the enzymes and concentration of metabolites of glycolysis and Rapoport-Lubering shunt, as well as morphological characteristics of erythrocytes from the rats with acute hyperammoniemia were determined. To elucidate the role of NMDA receptors in the above processes, MK-801, a non-competitive receptor antagonist, was used. Based on the obtained results it can be concluded that it is necessary to consider ammonium-induced morphofunctional disorders of erythrocytes and hemoglobinemia which can occur as a result of alterations in highly integrated networks of metabolic pathways may act as an additional systemic "erythrocytic" pathogenetic factor to prevent the onset and progression of cerebral hypoperfusion in hepatic encephalopathy accompanied by hyperammonemia.

Machine learning based prediction of chronic shunt-dependent hydrocephalus after spontaneous subarachnoid hemorrhage.

BACKGROUND: Chronic posthemorrhagic hydrocephalus often arises following spontaneous subarachnoid hemorrhage (SAH). Timely identification of patients predisposed to develop chronic shunt-dependent hydrocephalus may significantly enhance clinical outcomes. METHODS: We performed an analysis of 510 SAH-patients treated at our institution between 2013 and 2018. Clinical and radiological variables, including age, sex, Hunt & Hess grade, Fisher-Score, external ventricular drainage placement, central nervous system infection, aneurysm characteristics, and treatment modalities, were evaluated. Supervised machine learning models, trained and compared using Python and scikit-learn, were employed to predict chronic shunt-dependent hydrocephalus. Model performance was rigorously assessed through repeated cross-validation. To facilitate transparency and collaboration, we publicly released the dataset and code on GitHub (https://github.com/RISCSoftware/shuntclf) and developed an interactive web application (https://huggingface.co/spaces/risc42/shuntclf). RESULTS: Among the evaluated machine learning models, logistic regression exhibited superior performance, with an AUC-ROC of 0.819 and an AUC-PR of 0.482, along with the highest F1 score of 0.473. Although the balanced accuracy scores of the models were generally proximate, ranging from 0.735 to 0.764, logistic regression consistently outperform others in key metrics such as AUC-ROC and AUC-PR. Conversely, female gender and absence of aneurysm within the anterior communicating artery were associated with reduced shunt requirement likelihood. CONCLUSION: Machine learning models, including logistic regression, demonstrate strong predictive capability for early chronic shunt-dependent hydrocephalus following spontaneous SAH, which may potentially contribute to more timely shunt placement interventions. This predictive capability is supported by our web interface, which simplifies the application of these models, aiding clinicians in efficiently determining the need for shunt placement.

Evaluating the Safety and Efficacy of a Novel Glaucoma Drainage Device in High-Risk Adult Glaucoma Patients: A One-Year Pilot Study.

Background: We report on the 12-month safety and efficacy outcomes of a new non-valved glaucoma drainage device, the eyePlate-300 (Rheon Medical, Lausanne, Switzerland), in managing refractory glaucoma. Methods: A retrospective review was conducted on consecutive patients over 18 who underwent glaucoma drainage device (GDD) surgery with the eyePlate-300 after a single glaucoma consultation between February 2020 and April 2021, with at least 12 months of documented post-op follow-up. Results: A total of 16 eyes from 15 patients were included. Complete success was observed in 47% of patients and overall success in 83%. The mean IOP decreased from 31.5 mm Hg to 10.7 mm Hg (67% reduction from baseline), and the number of IOP-lowering drops was reduced from 3.1 to 0.7 at one year. The mean BCVA remained stable. No additional IOP-lowering surgeries were required, and no severe sight-threatening complications were noted. Conclusions: The initial one-year results suggest that the eyePlate could be a safe and effective device for reducing IOP in an ethnically diverse refractory glaucoma population. Further follow-up is necessary to determine the long-term safety and efficacy.

Single Posthepatic Portosystemic Shunt Communicated With Internal Thoracic Vein and Azygos Continuation of the Caudal Vena Cava in a Dog.

Computed tomography angiography (CTA) was performed under general anaesthesia on a 7-month-old toy poodle that was referred with the chief complaints of salivation and neurological symptoms. The CTA revealed a rare form of posthepatic portosystemic shunt (PSS) via the suspected persistent left umbilical vein communicating with the internal thoracic vein in addition to an azygos continuation of the caudal vena cava (CVC). The patient underwent surgery for partial ligation of PSS on Day 4 after the initial examination. On Day 71, after the initial examination, a second surgery was performed for complete ligation. Approximately 10 years have passed since the patient's second surgery, and he is still healthy, and generally in good condition. Although the morphology of the shunt in this case was unusual and was accompanied by an azygos continuation of the CVC, a favourable course of treatment was obtained by ligating the shunt vessel. This case report suggests that CTA can reveal the complex morphological characteristics like our case. Surgical treatment in this case resulted in favourable progress, similar to that in dogs with commonly observed extrahepatic PSS.

Outcome of Transjugular Intrahepatic Portosystemic Shunt in Patients with Cirrhosis and Refractory Hepatic Hydrothorax: A Systematic Review and Meta-analysis.

Background Around 5% of patients with cirrhosis of the liver develop hepatic hydrothorax (HH). For patients with refractory HH (RHH), transjugular intrahepatic portosystemic shunt (TIPS) has been investigated in small studies. Hence, the present meta-analysis aimed to summarize the current data on the outcome of TIPS in patients with RHH. Methods From inception through June 2023, MEDLINE, Embase, and Scopus were searched for studies analyzing the outcome of TIPS in RHH. Clinical response, adverse events (AEs), mortality, and shunt dysfunction were the primary outcomes assessed. The event rates with their 95% confidence interval were calculated using a random-effects model. Results A total of 12 studies ( n = 466) were included in the final analysis. The pooled complete and partial response rates were 47.2% (35.8-58.5%) and 25.5% (16.7-34.3%), respectively. The pooled incidences of serious AEs and post-TIPS liver failure after TIPS in RHH were 5.6% (2.1-9.0%) and 7.6% (3.1-12.1%), respectively. The pooled incidences of overall hepatic encephalopathy (HE) and severe HE nonresponsive to standard treatment after TIPS in RHH were 33.2% (20.0-46.4%) and 3.6% (0.4-6.8%), respectively. The pooled 1-month and 1-year mortality rates were 14.0% (8.3-19.6%) and 42.0% (33.5-50.4%), respectively. The pooled incidence of shunt dysfunction after TIPS in RHH was 24.2% (16.3-32.2%). Conclusion RHH has a modest response to TIPS in patients with cirrhosis, with only half having a complete response. Further studies are required to ascertain whether early TIPS can improve the outcome of patients with cirrhosis and HH.

Techniques for Identifying a Patent Foramen Ovale: Transthoracic Echocardiography, Transesophageal Echocardiography, Transcranial Doppler, Right Heart Catheterization.

Noninvasive and invasive imaging modalities play important roles for the detection of patent foramen ovale (PFO). Transthoracic echocardiography or transcranial Doppler bubble study can be used for initial noninvasive PFO screening. For diagnostic confirmation, transesophageal echocardiography bubble study can be utilized, a semiinvasive confirmatory test that can directly visualize a PFO. In selective cases when the diagnosis is in doubt, PFO can be accurately diagnosed invasively with right heart catheterization. Understanding the advantages and limitations of each diagnostic option will help clinicians choose the appropriate test for patients presenting with a PFO-associated condition who may benefit from percutaneous device closure.

Patent Foramen Ovale and Acute Mountain Sickness.

Acute mountain sickness (AMS) commonly plagues people who travel to high altitude and can be life threatening. Clinically, AMS is defined by a constellation of symptoms as outlined in the Lake Louise Criteria. The underlying etiology is thought to be related to a decrease in partial pressure of oxygen leading to tissue hypoxia. Patent foramen ovale (PFO) has been postulated to play a role in AMS through right-to-left shunt, which can worsen hypoxemia. Recent data demonstrate a higher prevalence of PFO in hikers with AMS. Future studies are needed to further elucidate the relationship between PFO and AMS.

Silicone allergy manifestation in pediatric ventriculoperitoneal shunting: navigating diagnostic challenges and customizing therapeutic approaches. Illustrative case.

BACKGROUND: A silicone allergy can significantly impact the efficacy of ventriculoperitoneal shunt devices used in hydrocephalus treatment. Its clinical presentation often resembles infectious ventriculitis, characterized by altered cerebrospinal fluid (CSF) parameters, including low glucose levels, elevated protein concentrations, and increased white blood cell counts predominantly comprising eosinophils. OBSERVATIONS: The authors report the case of an 18-month-old male who experienced recurrent shunt malfunction linked to CSF changes indicative of infectious ventriculitis. The patient underwent surgeries for suspected infection management. Notably, he exhibited increased eosinophil counts in both blood and CSF, as well as the development of neoformation tissue. This, along with the absence of microbial infection, indicated silicone hypersensitivity. While navigating medical device scarcity, innovative methods were employed to secure a silicone-free valve, markedly improving the patient's clinical outcome. LESSONS: Clinicians must be vigilant for silicone allergy in patients with ventriculoperitoneal shunts, particularly when elevated serum eosinophil counts and negative microbiological tests are present. This rare condition demands a multidisciplinary approach for timely diagnosis and management to reduce morbidity, unnecessary surgeries, and healthcare costs. The limited availability of non-silicone-based shunts further complicates management. This case emphasizes the need for considering silicone allergy in differential diagnoses, especially in pediatric patients. https://thejns.org/doi/10.3171/CASE2474.

A case of a tetralogy of Fallot patient treated only with classic Blalock-Taussig-Thomas shunt in modern life.

We showed images of classic Blalock-Taussig-Thomas shunt in a 35-year-old male patient with tetralogy of Fallot who underwent palliative surgery in 1992. It is a rare image echocardiography in our modern life.

Comment on, "Superb microvascular ultrasound is a promising non-invasive diagnostic tool to assess a ventriculoperitoneal shunt system function: a feasibility study".

This study by Brawanski et al. (2024) contributes significantly to neurosurgery by assessing ventriculoperitoneal shunt (VPS) function using superb microvascular ultrasound (SMI). The authors provide a thorough evaluation of SMI as a novel, non-invasive diagnostic tool, demonstrating its effectiveness in detecting cerebrospinal fluid (CSF) flow within VPS systems. By focusing on asymptomatic hydrocephalus patients, the study offers a less invasive alternative to traditional diagnostic methods, potentially reducing the need for exploratory surgeries. However, the study could have been strengthened by exploring the variability of SMI measurements under different physiological conditions and including symptomatic patients. Additionally, further analysis of the long-term reliability of SMI is needed. Future research should expand the study's scope to assess SMI's diagnostic capabilities across varied conditions and explore its integration with other non-invasive techniques, thereby enhancing its clinical utility in managing hydrocephalus and VPS functionality.

Interventions in Budd-Chiari syndrome: an updated review.

Budd Chiari syndrome is a potentially treatable disease, and imaging is the key to its diagnosis. Clinical presentations may vary, ranging from asymptomatic to fulminant disease. Subacute BCS is the most common type encountered in clinical practice, characterized by ascites, hepatosplenomegaly, dilated abdominal wall veins, and varicosities in the lower limb and scrotum. While hepatic vein thrombosis is the leading cause in the West, membranous and short segmental occlusion are predominant in the Asian populations. These geographical variations have an impact on the treatment algorithm in managing BCS. Anticoagulation alone often fails to prevent disease progression, demanding further interventional therapy. Interventional therapy carries a lower morbidity and mortality than surgery. Anatomical recanalization and portosystemic shunting form the basis of endovascular management. Membranous or short-segment occlusion are best treated by angioplasty, which restores the physiological venous outflow and possibly disease reversal. Suboptimal results with angioplasty require stenting. Transjugular intrahepatic shunt (TIPS) or direct IVC to portal vein shunt (DIPS) decompresses the portal pressure and reduces the sinusoidal congestion, which in turn diminishes hepatocellular damage and hepatic fibrosis. Despite its ability to modify the disease course, TIPS carries several procedure and shunt-related complications, mainly hepatic encephalopathy. Thus, anatomical recanalization precedes TIPS in the traditional step-up approach in managing BCS. However, this concept is challenged by some authors, necessitating future reseach. TIPS is a valid bridge therapy in BCS with acute live failure awaiting liver transplantation. Despite all, interventional therapies fail in a subset of BCS patients, leaving them with only option of liver transplantation.