Management of migrating intracranial bullet fragments in a 13-year-old female after firearm brain injury: technical and surgical nuances.

INTRODUCTION: We present the challenges and nuances of management in a rare case of multiple migrating intracranial fragments after pediatric gunshot wound to the head (GSWH). CASE PRESENTATION: A 13-year-old girl suffered left parietal GSWH, with new neurologic decline 3 days after initial debridement. Serial imaging showed the largest intracranial fragments had migrated into the left trigone, and descended further with head of bed (HOB) elevation. HOB was iteratively decreased, with concurrent intracranial pressure monitoring. After extubation, with an alert and stable neurologic exam, HOB was decreased to -15 degrees, allowing gravity-assisted migration of the fragments to an anatomically favorable position within the left occipital horn. The patient underwent occipital craniotomy for fragment retrieval on hospital day 27. Two large and >20 smaller fragments were retrieved using neuronavigation and intraoperative ultrasound. Forensics showed these to be .45 caliber handgun bullet fragments. The patient recovered well after 2-months of intensive inpatient rehabilitation. DISCUSSION: During new neurologic decline after GSWH, bullet migration must be considered and serial cranial imaging is requisite. Surgical retrieval of deep fragments requires judicious planning to minimize further injury. Tightly controlled HOB adjustments with gravity assistance for repositioning of fragments may have utility in optimizing anatomic favorability prior to surgery.

Targeting Accuracy and Clinical Outcomes of Awake versus Asleep Interventional Magnetic Resonance Imaging-Guided Deep Brain Stimulation for Parkinson's Disease: The University of California, San Francisco Experience.

BACKGROUND: Interventional MRI (iMRI)-guided implantation of deep brain stimulator (DBS) leads has been developed to treat patients with Parkinson's disease (PD) without the need for awake testing. OBJECTIVE: Direct comparisons of targeting accuracy and clinical outcomes for awake stereotactic with asleep iMRI-DBS for PD are limited. METHODS: We performed a retrospective review of patients with PD who underwent awake or iMRI-guided DBS surgery targeting the subthalamic nucleus or globus pallidus interna between 2013 and 2019 at our institution. Outcome measures included Unified Parkinson's Disease Rating Scale Part III scores, levodopa equivalent daily dose, radial error between intended and actual lead locations, stimulation parameters, and complications. RESULTS: Of the 218 patients included in the study, the iMRI cohort had smaller radial errors (iMRI: 1.27 ± 0.72 mm, awake: 1.59 ± 0.96 mm, P < .01) and fewer lead passes (iMRI: 1.0 ± 0.16, awake: 1.2 ± 0.41, P < .01). Changes in Unified Parkinson's Disease Rating Scale were similar between modalities, but awake cases had a greater reduction in levodopa equivalent daily dose than iMRI cases ( P < .01), which was attributed to the greater number of awake subthalamic nucleus cases on multivariate analysis. Effective clinical contacts used for stimulation, side effect thresholds, and complication rates were similar between modalities. CONCLUSION: Although iMRI-DBS may result in more accurate lead placement for intended target compared with awake-DBS, clinical outcomes were similar between surgical approaches. Ultimately, patient preference and surgeon experience with a given DBS technique should be the main factors when determining the "best" method for DBS implantation.

A Case of Torticollis in an 8-Month-Old Infant Caused by Posterior Fossa Arachnoid Cyst: An Important Entity for Differential Diagnosis.

Torticollis is a clinical diagnosis with heterogeneous causes. We present an unusual case of acquired torticollis in an 8-month-old female infant with a large cerebellopontine angle arachnoid cyst. Symptoms resolved after surgical fenestration. Non-traumatic acquired or new-onset torticollis requires brain imaging, and posterior fossa lesions are an important entity in the differential for pediatric clinicians.

Circuit and molecular architecture of a ventral hippocampal network.

The ventral hippocampus (vHPC) is a critical hub in networks that process emotional information. While recent studies have indicated that ventral CA1 (vCA1) projection neurons are functionally dissociable, the basic principles of how the inputs and outputs of vCA1 are organized remain unclear. Here, we used viral and sequencing approaches to define the logic of the extended vCA1 circuit. Using high-throughput sequencing of genetically barcoded neurons (MAPseq) to map the axonal projections of thousands of vCA1 neurons, we identify a population of neurons that simultaneously broadcast information to multiple areas known to regulate the stress axis and approach-avoidance behavior. Through molecular profiling and viral input-output tracing of vCA1 projection neurons, we show how neurons with distinct projection targets may differ in their inputs and transcriptional signatures. These studies reveal new organizational principles of vCA1 that may underlie its functional heterogeneity.