Ventricular Access Utilizing Cutaneous Reference Points: Statistical Analysis and Proposal of a New Ventricular Entry Point.

OBJECTIVES: Perform radiologic measurements and analysis of normal brain computed tomography (CT) scans; delineate a new ventricular entry point from cutaneous landmarks, highlighting the potential surgical implications of these findings. METHODS: Six radiologic distances (AR; BR; AL; BL, C, and D) were measured in normal brain CT scans using Horos software. Statistical analysis of the measurements was performed with minitab18 software based on age, sex, and side. RESULTS: 132 brain CT scans were analyzed, yielding the following mean results: AR distance: 2.1 cm; BR distance: 7 cm; AL distance: 2.1 cm; BL distance: 7.1 cm; C distance: 12.4 cm; D distance: 7 cm; new ventricular entry point: 12.4 cm posterior to the nasion, and 2.1 cm lateral to the midline. CONCLUSIONS: The freehand technique for accessing the lateral ventricles is a common neurosurgical procedure but is often accompanied by complications. To address this, we suggest a novel entry point for ventricular access, determined by cutaneous reference points. This point is situated 12.4 cm posterior to the nasion along the midline and 2.1 cm lateral to the midline. Although our findings may play a role in presurgical planning for ventricular pathologies, future prospective studies are warranted.

"Ping-pong" fracture: An exclusive entity of neonates and infants? A case analysis and literature review.

Background: "Ping-pong" fractures are a type of depressed fracture in which there is no rupture of the inner or outer table of the skull. It is produced by incomplete bone mineralization. Its appearance is frequent during neonatal and infant ages and is extremely rare outside of these age periods. The objective of this article is to present the case of a 16-year-old patient who presented a "ping-pong" fracture after a traumatic brain injury (TBI) and discuss the underlying physiopathogenesis of these types of fractures. Case Description: A 16-year-old patient presented to the emergency department with a TBI, referring headaches and nausea. Non-contrast brain computed tomography displayed a left parietal "ping-pong" fracture. Laboratory tests showed hypocalcemia, subsequently diagnosing hypoparathyroidism. The patient remained under observation for 48 h. He was managed conservatively and started on calcium carbonate and vitamin D supplements with a favorable evolution. Hospital discharge was granted with TBI discharge instructions and warning signs. Conclusion: The age of presentation of our case was atypical, according to the reported literature. When faced with a "ping-pong" fracture outside of an early age, underlying bone pathologies must be ruled out, which could potentially generate incomplete bone mineralization of the skull.

Which biological pathways are responsible for the late appearance of brain metastases in renal cell carcinoma? Analysis of eight cases.

Background: Renal cell carcinoma (RCC) represents 1% of all cancers and its brain metastases amount to 8.1% of all metastatic tumors. Late brain metastases are defined as tumors that appear 10 years after diagnosis of the primary lesion. The objective of this work is to discuss which biological pathways are responsible for the late appearance of these metastases analyzing eight cases. Case Description: We report here eight cases of late brain metastases of RCC treated between 2018 and 2021. Patients consulted for different clinical complaints. Brain magnetic resonance imaging and computed tomography scan were performed on all patients. They were treated by complete surgical resection plus radiosurgery or by radiosurgery alone. The histology of most metastases showed clear cell RCC. Conclusion: In the presence of a patient with an intracranial tumor and a history of RCC with more than 10 years of evolution, the presence of late metastasis should always be considered. There are many theories described in the literature that try to explain the late appearance of brain metastases from RCC (low mitotic index, impaired immune system, cross talk, self-seeding, and among others).

Distance Between the Corpus Callosum and the Falx Cerebri: A Little Explored Measure with Potential Surgical Implication.

OBJECTIVE: To perform measurements in normal brain imaging studies from the free edge of the falx cerebri to the genu and the body of the corpus callosum and perform a statistical analysis based on age, type of study, and sex highlighting potential surgical implication of these measurements. METHODS: In 193 normal brain imaging studies, 3 anatomical points of the corpus callosum were used to measure the distance to the falx cerebri. Horos and RadiAnt DICOM Viewer software were used to perform the measurements. Statistical analysis of data was performed with Minitab18 software. RESULTS: The results obtained in computed tomography (CT) studies were: distance A, mean 2.1065 cm; distance B, mean 2.2677 cm; distance C, mean 1.765 cm. The results obtained in magnetic resonance imaging studies were: distance A, mean 1.7148 cm; distance B, mean 2.1197 cm; distance C, mean 1.5321 cm. Statistically significant differences were obtained in measurements related to the type of study and in measurements made in CT studies related to age. CONCLUSIONS: There is a distance from the free edge of the falx cerebri to the genu and body of the corpus callosum of at least 1 cm in both CT and magnetic resonance imaging studies of normal brains. Statistically significant differences were found in the measurements in relation to the type of study and in relation to age in the measurements made in CT studies. These measurements could be important in determining the extent of bone resection in certain types of decompressive craniectomies.

A new, readily accessed and low-cost, device for treating depressed ping pong fractures non-surgically: Technical note.

OBJECTIVE: The aim of this paper is to describe a low-cost and readily accessed Manual Aspiration Reduction System (MARS) for use treating ping-pong fractures in three patients. METHODS: The MARS is composed of a pediatric anesthesia mask, part of a macro dripper, a 3-way stopcock, and two 60-ml syringes. Prior to its use in our patient, the system was tested on five adult volunteers to maximum negative pressure, and none reported pain during the procedure or experienced any other complication. We present three clinical cases of patients with depressed ping-pong fracture who were treated with the MARS at the bedside without anesthesia. The patients were monitored by the neonatology team throughout the procedure. RESULTS: Skull radiography revealed reduction of the fracture after the procedure performed with the MARS in all patients. The transfontanellar ultrasound and follow-up neurological examination were normal. The patient progressed favorably and was discharged from our service after 24 h. CONCLUSIONS: Due to its components, the MARS is a low-cost and readily accessed system. In this case, it permitted satisfactory reduction of a ping-pong fracture in all patients. This system should greatly simplify the treatment of such fractures.

A new, low-cost device to treat depressed "ping-pong" fractures non-surgically: technical note.

OBJECTIVE: The aim of this paper is to describe a low-cost and readily accessed Manual Aspiration Reduction System (MARS) for use treating neonatal ping-pong fractures. METHODS: The MARS is composed of a pediatric anesthesia mask, part of a macro dripper, a 3-way stopcock, and two 60-ml syringes. Prior to its use in our patient, the system was tested on five adult volunteers to maximum negative pressure, and none reported pain during the procedure or experienced any other complication. CLINICAL CASE: A 15-day-old premature girl presented with a congenital ping-pong fracture. Her skull X-ray revealed a right parietal fracture. Neurological examination and transfontanellar ultrasound were normal. Treatment using the MARS was performed at the patient's bedside without sedation or anesthesia. The patient was monitored by the neonatology team throughout. RESULTS: Skull radiography revealed reduction of the fracture after the procedure performed with the MARS. The transfontanellar ultrasound and follow-up neurological examination were normal. The patient progressed favorably and was discharged from our service after 24 h. CONCLUSIONS: Due to its components, the MARS is a low-cost and readily accessed system. In this case, it permitted satisfactory reduction of a ping-pong parietal fracture. This system should greatly simplify the treatment of such fractures.