Diffuse intrinsic pontine gliomas (DIPGs) are aggressive and malignant tumors of the brainstem. Stereotactic biopsy can obtain molecular and genetic information for diagnostic and potentially therapeutic purposes. However, there is no consensus on the safety of biopsy or effect on survival. The authors aimed to characterize neurological risk associated with and the effect of stereotactic biopsy on survival among patients with DIPGs.
A systematic review was performed in accordance with PRISMA guidelines to identify all studies examining pediatric patients with DIPG who underwent stereotactic biopsy. The search strategy was deployed in PubMed, Embase, and Scopus. The quality of studies was assessed using the Grading of Recommendations, Assessment, Development and Evaluation system, and risk of bias was evaluated with the Cochrane Risk of Bias in Nonrandomized Studies-of Interventions tool. Bibliographic, demographic, clinical, and outcome data were extracted from studies meeting inclusion criteria.
Of 2634 resultant articles, 13 were included, representing 192 patients undergoing biopsy. The weighted mean age at diagnosis was 7.5 years (range 0.5-17 years). There was an overall neurosurgical complication rate of 13.02% (25/192). The most common neurosurgical complication was cranial nerve palsy (4.2%, 8/192), of which cranial nerve VII was the most common (37.5%, 3/8). The second most common complication was perioperative hemorrhage (3.6%, 7/192), followed by hemiparesis (2.1%, 4/192), speech disorders (1.6%, 3/192) such as dysarthria and dysphasia, and movement disorders (1.0%, 2/192). Hydrocephalus was less commonly reported (0.5%, 1/192), and there were no complications relating to wound infection/dehiscence (0%, 0/192) or CSF leak (0%, 0/192). No mortality was specifically attributed to biopsy. Diagnostic yield of biopsy revealed a weighted mean of 97.4% (range 91%-100%). Of the studies reporting survival data, 37.6% (32/85) of patients died within the study follow-up period (range 2 weeks-48 months). The mean overall survival in patients undergoing biopsy was 9.73 months (SD 0.68, median 10 months, range 6-13 months).
Children with DIPGs undergoing biopsy have mild to moderate rates of neurosurgical complications and no excessive morbidity. With reasonably acceptable surgical risk and high diagnostic yield, stereotactic biopsy of DIPGs can allow for characterization of patient-specific molecular and genetic features that may influence prognosis and the development of future therapeutic strategies.

Stereotactic biopsy is used for sampling of suspicious non-palpable lesions identified on mammography or digital breast tomosynthesis which are not visible on ultrasound. Stereotactic biopsy is preferable to surgical excision biopsy and helps avoid surgery for benign lesions. Providing tissue diagnosis in patients with early breast cancer may help in formulating a management strategy. Stereotactic biopsy can be carried out using either a dedicated prone table with the patient lying prone or an upright mammographic add-on system with the patient in a sitting or lateral decubitus position. This review focuses on the advantages and disadvantages of both these systems, the indications, contraindications and the complications inherent with this technique. The important pitfalls and their management as well as ways to ensure quality assurance have also been elaborated upon. Data regarding uptake of stereotactic biopsy in other parts of the world have been discussed using evidence from existing registries and databases and attempts made to quantify the need of the technique in the Indian set-up. In the absence of a national breast screening programme and limited resources in India, a hub and spoke model has been proposed as a viable model for healthcare providers for providing stereotactic biopsy.

The frame-based stereotactic biopsy is a minimally invasive technique that allows us to obtain a sample of brain tissue for subsequent diagnosis and treatment. The scope of this article is to review the published data related to the factors that could condition its diagnostic yield, and the appearance of post-biopsy hemorrhagic complications. PubMed search, last updated June 2020, was conducted using the terms \"stereotactic biopsy\", \"diagnostic yield\" and \"intracranial post-biopsy hemorrhage\". A total of 38 studies, that showed descriptive or analytical results, were included, and reviewed. Our literature review show that some characteristics of the lesion and surgical procedure peculiarities are significantly related with the effectiveness and safety of the technique. In this way, they must be taken into account in order to optimize its results.

UNASSIGNED: Stereotactic brain biopsy techniques have been a focus of rapid technological innovation. The recent advent of frameless stereotaxy has invited the question of whether it can provide the same diagnostic yield as frame-based techniques, without increasing risk of harm to patients. The goal of this meta-analysis was to compare each of these techniques in terms of yield and safety.
UNASSIGNED: We independently searched four databases for English studies comparing frameless and frame-based stereotactic brain biopsies. Our primary outcome was biopsy diagnostic yield. Our secondary outcomes included mortality, morbidity (e.g., symptomatic postbiopsy intracranial hemorrhage, asymptomatic postbiopsy intracranial hemorrhage, new postbiopsy neurological deficit, and postbiopsy seizure), and frequency of repeat biopsy. We calculated pooled estimates and relative risks for dichotomous outcomes using Review Manager 5.3, with corresponding 95% confidence intervals.
UNASSIGNED: A total of 3256 stereotactic brain biopsies (2050 frame based and 1206 frameless), from 20 studies, were included in our final analysis. The results did not demonstrate any significant difference between the two stereotactic systems in terms of diagnostic yield (risk ratio [RR] 1.00, 95% confidence interval [CI] 0.99-1.02, P = 0.64, I2 = 0%). The only significant difference was the increased frequency of asymptomatic hemorrhages in the frameless group (RR 1.37, 95% CI 1.06-1.75, P = 0.01, I2 = 0%). Application of Grading of Recommendations Assessment, Development, and Evaluation to the results yielded very low quality of all outcomes.
UNASSIGNED: Based on very low-quality evidence, both frame-based and frameless stereotaxy are safe and effective for biopsy of intracranial tumors. Further study of patient preference and cost comparing analysis is required to identify if either modality should be preferred.

The frame-based stereotactic biopsy is a minimally invasive technique that allows us to obtain a sample of brain tissue for subsequent diagnosis and treatment. The scope of this article is to review the published data related to the factors that could condition its diagnostic yield, and the appearance of post-biopsy hemorrhagic complications. PubMed search, last updated June 2020, was conducted using the terms \"stereotactic biopsy\", \"diagnostic yield\" and \"intracranial post-biopsy hemorrhage\". A total of 38 studies, that showed descriptive or analytical results, were included, and reviewed. Our literature review show that some characteristics of the lesion and surgical procedure peculiarities are significantly related with the effectiveness and safety of the technique. In this way, they must be taken into account in order to optimize its results.

To describe a case series of children with thalamic tumors treated at our institution in a 5-year period.
A retrospective and observational study was performed. The records of 15 patients between 2013 and 2018 were analyzed.
From 2013 to 2018, 15 patients were treated at our institution. The male to female index was 1.5, and the median age was 8.9 (IQR 4.75-13). Seven (46%) tumors were left-sided, seven (46%) were right-sided, and one (6%) was bilateral. All patients were symptomatic at the time of treatment. Motor deficit was the most common form of presentation (73%). Gross-total resection was performed in two (13.3%) patients, subtotal resection was performed in two other patients (13.3%), and for the rest of the patients (73.3%), the chosen surgical approach was a stereotactic-guided biopsy. The average of procedures was 3.4, mostly related to the treatment for hydrocephalus. Twelve patients (80%) received treatment for hydrocephalus. Nine patients (75%) were treated with ventriculoperitoneal shunts, and four patients (33%) underwent endoscopic third ventriculostomy. High-grade tumors predominated. Grade IV tumors were diagnosed in six patients (40%), followed by grade III in four patients (26.6%), grade II in three (20%) patients, and grade I in two (13.3%) patients. Chemotherapy was given in 93% of the cases, being temozolomide, the most used drug.
The clinical and surgical approaches for thalamic tumors in children have changed over time. At our institution, the lesser invasive surgical procedures are now being used more frequently.

BACKGROUND: The purpose of this study was to determine the relationship between the radiological and histopathological distribution of the cerebral lesions diagnosed with stereotactic biopsy (STB) procedure and its outcomes.
METHODS: In the current study, a retrospective analysis of 83 patients that underwent the STB in our clinic from January 2011 to December 2015 was made. T1-weighted contrast-enhanced cranial magnetic resonance imaging examinations were performed on patients on whom Leksell stereotactic frame system was installed. The histopathological and the radiological data derived from the STB procedure were classified.
RESULTS: In terms of localization, glial tumor (56.6%) was the most common lesion in all regions, except for the multifocal lesions. Contrary to the common knowledge, lymphoma (14.4%) was found to be the most common lesion among multifocal lesions. The success of obtaining positive STB samples in the current series was 95.2% and the complication rate was 3.6%.
CONCLUSIONS: Had a routine computed tomography scan been performed on each patient in this series, the number of clinically insignificant small intracerebral hematomas would have probably been higher. Nevertheless, the rate of the STB sampling accuracy and the complication rate were similar to those reported in the relevant literature.

In this short review, the authors performed a database search and summarize current knowledge of the management of patients with pineal cysts (PCs) and investigate the role of surgical treatment. The scientific literature on the surgical treatment of PCs is sparse and encompasses only case series with little over 200 operated patients combined. All included papers reported favorable results after pineal cyst surgery with improvement of symptoms in most patients. Microsurgical resection of PCs, preferably using the supracerebellar-infratentorial approach, could be considered as a viable treatment option in symptomatic patients. Even patients with non-specific symptoms are reported to improve after surgery. However, evidence offered by this literature review is very limited and therefore our conclusions must be tempered by the restricted set of data. For ethical reasons, a randomized controlled trial is not an acceptable approach, and therefore patient registry could be a useful tool to identify a subset of symptomatic patients that might benefit from pineal cyst resection.

Stereotactic needle biopsy, a standard of care for acquiring deep-seated pathology, has limitations and risks in some situations. We present an uncommon case with basal ganglia dematiaceous mycetoma. Due to the firm consistency of the lesion, the initial stereotactic needle biopsy failed to provide a diagnosis. In a second operation, transtubular excisional biopsy was successfully performed to remove the entire mycetoma. We reviewed recent case series of transtubular approaches to deep-seated brain lesions and suggest this method could be a rescue for a non-diagnostic stereotactic needle biopsy and even may be the approach of choice in some cases.

OBJECTIVE Recent studies have shed light on the molecular makeup of diffuse intrinsic pontine gliomas and led to the identification of potential treatment targets for these lesions, which account for the majority of pediatric brainstem tumors (pedBSTs). Therefore, stereotactic biopsy-driven molecular characterization of pedBSTs may become an important prerequisite for the management of these fatal brain tumors. The authors conducted a systemic review and meta-analysis to precisely determine the safety and diagnostic success of stereotactic biopsy of pedBSTs. METHODS A systematic search of PubMed, EMBASE, and the Web of Science yielded 944 potentially eligible abstracts. Meta-analysis was conducted on 18 studies (including the authors\' own institutional series), describing a total of 735 biopsy procedures for pedBSTs. The primary outcome measures were diagnostic success and procedure-related complications. Pooled estimates were calculated based on the Freeman-Tukey double-arcsine transformation and DerSimonian-Laird random-effects model. Heterogeneity, sensitivity, and meta-regression analyses were also conducted. RESULTS The weighted average proportions across the analyzed studies were 96.1% (95% CI 93.5%-98.1%) for diagnostic success, 6.7% (95% CI 4.2%-9.6%) for overall morbidity, 0.6% (95% CI 0.2%-1.4%) for permanent morbidity, and 0.6% (95% CI 0.2%-1.3%) for mortality. Subgroup analyses at the study level identified no significant correlation between the outcome measures and the distribution of the chosen biopsy trajectories (transfrontal vs transcerebellar), age, year of publication, or the number of biopsy procedures annually performed in each center. CONCLUSION Stereotactic biopsy of pedBSTs is safe and allows successful tissue sampling as a prerequisite for the molecular characterization and the identification of potentially druggable targets toward more individualized treatment concepts to improve the outcome for children harboring such lesions.