A multi-modal approach to computer-assisted deep brain stimulation trajectory planning

Purpose

Both frame-based and frameless approaches to deep brain stimulation (DBS) require planning of insertion trajectories that mitigate hemorrhagic risk and loss of neurological function. Currently, this is done by manual inspection of multiple potential electrode trajectories on MR-imaging data. We propose and validate a method for computer-assisted DBS trajectory planning.

Method

Our framework integrates multi-modal MRI analysis (T1w, SWI, TOF-MRA) to compute suitable DBS trajectories that optimize the avoidance of specific critical brain structures. A cylinder model is used to process each trajectory and to evaluate complex surgical constraints described via a combination of binary and fuzzy segmented datasets. The framework automatically aggregates the multiple constraints into a unique ranking of recommended low-risk trajectories. Candidate trajectories are represented as a few well-defined cortical entry patches of best-ranked trajectories and presented to the neurosurgeon for final trajectory selection.

Results

The proposed algorithm permits a search space containing over 8,000 possible trajectories to be processed in less than 20 s. A retrospective analysis on 14 DBS cases of patients with severe Parkinson’s disease reveals that our framework can improve the simultaneous optimization of many pre-formulated surgical constraints. Furthermore, all automatically computed trajectories were evaluated by two neurosurgeons, were judged suitable for surgery and, in many cases, were judged preferable or equivalent to the manually planned trajectories used during the operation.

Conclusions

This work provides neurosurgeons with an intuitive and flexible decision-support system that allows objective and patient-specific optimization of DBS lead trajectories, which should improve insertion safety and reduce surgical time.

     

Development and characterization of DNAzyme candidates demonstrating significant efficiency against human rhinoviruses

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Rapid culture-amplified immunofluorescent test for the detection of human rhinoviruses in clinical samples: Evidence of a common epitope in culture

Hepatitis B surface antigen (HBsAg) and hepatitis C virus (HCV) RNA were surveyed in patients in Yogyakarta, Indonesia, and their subtypes and genotypes were determined by serological methods and polymerase chain reaction with type-specific primers, respectively. Of 149 patients with chronic liver disease including 24with chronic hepatitis, 86 with liver cirrhosis, and 39 with primary hepatocellular carcinoma, HBsAg was detected in 40 (27%) and HCV RNA in 48 (32%); one patient was positive both for HBsAg and HCV RNA. Thus, the cause of chronic liver disease was not identified in 62 (42%) patients. Of 58 patients on maintenance hemodialysis, four (7%) were positive for HBsAg and 44 (76%) for HCV RNA. Subtype adw was found in 34 (74%) of 46 HBsAg samples and adr in five (11%); compound subtypes, such as adyw and adyr were detected in the remaining seven (15%). Among HCV RNA samples from 48 patients with chronic liver disease, 23 (48%) were of genotype II, 17 (35%) of genotype III and one (2%) of genotype V, in a distribution strikingly different from that of 44 samples from patients on maintenance hemodialysis, 39 (89%) of which were of genotype I and only one (2%) of genotype II. Genotypes were not classifiable in seven (15%) patients with liver disease and four (9%) patients on hemodialysis despite high HCV RNA titers in them all. These results indicate that different HCV genotypes prevail in patients with distinct diseases, as well as unclassifiable HCV genotypes in Indonesia. © 1994 Wiley-Liss, Inc.     

Efficacy of routine post-operative head computed tomography on cranial surgery patients outcome

Objectives:To identify the role of routine postoperative head CT in changing postoperative management after elective craniotomies.Methods:We conducted a retrospective study on adult patients who underwent cranial surgery. Exclusion criteria includes cranial CTs done postoperatively for urgent clinical indications, pediatric patients, CSF diversion procedures and sedated patients. Patients were placed into “positive” group if the physical assessment changed from the baseline in the form of clinical deterioration, and the “negative” group if the exam did not change. The data then were analyzed to identify which patients needed further medical or surgical management based on CT findings only with “negative” physical examination.Results:Total of 222 were included in the study. 151 patients had negative physical examination. Only 8 out of 151 patients had positive CT findings. Two patients out of 222 (0.9%) had a negative physical exam and positive CT findings that required additional action that wouldn’t be done urgently without routine postoperative brain CT. Only one patient out of 222 (0.4%) who was re-operated urgently based CT findings only and negative physical examination.Conclusion:Routine postoperative routine brain CT did not alter the course of medical management, even in the presence of significant radiological findings.

Neurosurgical patients have high early postoperative complications in comparison with other surgical domains.1 Postoperative brain CT is done routinely after cranial procedures to predict the possibility of early complications, including hemorrhage and significant brain edema.2 Other less urgent indications are the gross assessment of the extent of resection and ventricular catheter placement in cerebrospinal fluid diversion procedures.3 Imaging studies in our institute are done routinely for the postoperative cranial surgeries, even in the absence of clinical indication or postoperative complications; thus, raising suspicion about the role and efficacy of routine postoperative imaging.In this study, the aim is to determine the necessity of postoperative head CT scan in cranial surgeries to identify early complications, and its role in patient care, outcomes, and costs, with a review of the literature.     

Description of the parasite <Emphasis Type="Italic">Wucheria Bancrofti Microfilariae</Emphasis> identified in follicular fluid following transvaginal oocyte retrieval

Introduction  

This case study presents an unusual finding of filarial infection within follicular fluid obtained during an in vitro fertilization (IVF) oocyte retrieval procedure.     

Evaluation of Acute and Subacute Toxicity and LC-MS/MS Compositional Alkaloid Determination of the Hydroethanolic Extract of Dysphania ambrosioides (L.) Mosyakin and Clemants Flowers

Dysphania ambrosioides (L.) Mosyakin and Clemants is a medicinal plant that has traditionally been used to cure a range of diseases. There has been no thorough investigation of the potential toxicity of this plant. The objective of this study is to assess the acute and subacute toxicity of D. ambrosioides hydroethanolic extract (DAHE), as well as it alkaloids composition, utilizing LC-MS/MS analysis. An in silico approach was applied to determine pharmacokinetic parameters and to predict the toxicity of D. ambrosioides identified alkaloids. A 14-day treatment with a single oral dose of 1–7 g/kg was carried out to investigate acute toxicity. DAHE was given orally at dosages of 5, 50, and 500 mg/kg for 15 days in the subacute toxicity investigation, and body weight and biochemical parameters were evaluated. Livers, kidneys, lungs, and heart were examined histologically. Chromatographic investigation revealed the existence of nine alkaloids, with N-formylnorgalanthamine being the most prevalent. The oral LD₅₀ value of DAHE was found to be 5000 mg/kg in an acute toxicity study. No variations were observed with respect to food intake, water consumption, mortality, or body and organ weight in the subacute toxicity study. On the other hand, DAHE (500 mg/kg) significantly enhanced alanineaminotransferase, aspartate aminotransferase, and urea. Liver and kidney histological examinations revealed modest infiltration of hepatocyte trabeculae by inflammatory cells in the liver and slight alteration in the kidney histoarchitecture. According to our findings, DAHE exhibits low to moderate toxicity.     

Human leucocyte antigen-matched related haematopoietic stem cell transplantation using low-dose cyclophosphamide,fludarabine and thymoglobulin in children with severe aplastic anaemia

When human leucocyte antigen-matched related donors are available, haematopoietic stem cell transplantation (HSCT) in children with severe aplastic anaemia (SAA) represents the standard of care. Cyclophosphamide (Cy) 200 mg/kg and anti-thymocyte globulin (ATG) are frequently administered, but to-date, no standard conditioning regimen exists. In this study, we investigated the efficacy of a unified HSCT conditioning protocol consisting of low-dose Cy 80 mg/kg, fludarabine and ATG. Data were reviewed from children aged ≤14 years with either acquired SAA or non-Fanconi anaemia inherited bone marrow failure syndrome (IBMFS) between 2011 and 2022 at various Saudi institutions. Graft-versus-host disease (GVHD) prophylaxis included mycophenolate mofetil and calcineurin inhibitors. HSCT was performed in 32 children (17 females and 15 males). Nine patients had deleterious mutations (two ERCC6L2, two ANKRD26, two TINF2, one LZTFL1, one RTEL1 and one DNAJC21). Four patients had short telomeres. All 32 patients engrafted successfully. At 3 years post-transplant, the event-free survival was 93% and overall survival was 95%. Two patients experienced secondary graft failure or myelodysplastic syndrome. A low probability of GVHD was observed (one acute GVHD II and one mild chronic GVHD). These data highlight how HSCT using low-dose Cy as part of a fludarabine-based regimen is safe and effective in SAA/non-Fanconi anaemia IBMFS.     

The relationship between genetic profiling, clinicopathological factors and survival in patients undergoing surgery for node-negative colorectal cancer: 10-year follow-up

Purpose

The introduction of the bowel cancer screening programme has resulted in increasing numbers of patients being diagnosed with node-negative disease. Unfortunately, approximately 30 % will develop recurrence following surgery. Given the toxicity associated with adjuvant chemotherapy, it is important to identify high-risk patients who may benefit from adjuvant therapy. This study aims to identify which clinicopathological factors and genetic profiling markers predict outcome in node-negative disease.

Methods

Forty-nine microsatellite stable (MSS) patients undergoing curative resection between 1991 and 1993 were included. Local immune response was assessed by Klintrup criteria and vascular invasion status assessed through Miller’s elastin staining. Comparative genomic hybridisation (CGH) on a range of loci provided data on allelic imbalance. Analysis of survival included clinicopathological and CGH data in a multivariate (Cox) model.

Results

On binary logistical regression analysis, 4p deletion was independently associated with low Klintrup score (HR 0.16; 95 % CI (0.03–0.96); P = 0.045), venous invasion (HR 4.19; 95 % CI (1.08–16.29); P = 0.039) and higher Dukes’ stage (HR 6.43; 95 % CI (1.22–33.97); P = 0.028). Minimum follow-up was 109 months and there were 24 cancer deaths. On multivariate analysis, high Klintrup score (HR 0.33; 95 % CI (0.12–0.93); P = 0.036), 4p? (HR 4.01; 95 % CI (1.58–10.21); P = 0.004) and 5q? (HR 3.81; 95 % CI (1.54–9.47); P = 0.004) were significantly associated with survival.

Conclusion

4p?, 5q? and low Klintrup score were independently associated with poor cancer-specific survival in node-negative MSS colorectal cancer. Confirmatory work in a larger cohort is needed to determine whether these markers may be used to identify patients who may benefit from adjuvant chemotherapy.     

Fatigue and severity of rheumatoid arthritis in Moroccan patients

The aim of this study was to assess fatigue aspects in Moroccan patients with rheumatoid arthritis (RA) and its relationships with disease-specific variables especially parameters of functional and structural severity. A total of 248 patients with RA were included. Patients’ and disease characteristics were identified. Disease activity was measured clinically using physical examination, biologically and by the disease activity scores (DAS28). Radiographs were evaluated by using Sharp’s method as modified by van der Heijde. Functional disability was measured by using the Moroccan version of Health Assessment Questionnaire (HAQ). Immunological abnormalities and treatment (doses and duration) were identified. Fatigue was evaluated by using a 0–100 visual analogue scale (VAS fatigue) and the multidimensional assessment of fatigue (MAF). Quality of life (QoL) was assessed using the Arabic version of the generic instrument SF-36. The mean age of patients was 47.5?±?11.7?years [25–72]; 37.5% of patients had a high activity of disease and 11.3% were in remission. The mean Sharp score was 107.13?±?91, and the mean score of HAQ was 1.40?±?0.63. All domains of QoL were deteriorated; 89.51% of our patients experienced fatigue. The mean total score of MAF was 30.21?±?11.32. A low level of education, low socioeconomic status, atlantoaxial subluxation, hip involvement, the presence of a Sj?gren syndrome, and cigarette smoking had a negative impact on fatigue scores. The severity of fatigue was correlated with the duration of RA, the intensity of joint pain, the activity of disease, the importance of structural damage, the degree of functional impairment, and the rate of anti-cyclic citrullinated protein (CCP) antibodies (P?<?0.05). Patients receiving methotrexate had better scores of fatigue. Also, severity of fatigue was correlated with the deterioration of all domains of QoL. Fatigue is a major issue for our patients with RA and must be included in the routine assessment of patients. In our sample, fatigue appears to be related to disease activity, functional disability, structural damage, and immunological status and had a negative impact on QoL.