Novel entry point for intraoperative ventricular puncture during the transsylvian approach

Neuroanatomical refinement of Kocher's point for enhanced precision in ventriculostomy: A technical note and a literature review

Background

This study was designed to assess the effectiveness and safety of using a modified Kocher's point for ventriculostomy using endoscopic third ventriculostomy (ETV) and external ventricular drainage (EVD) in 200 patients at PAR Private Hospital in Erbil, Iraqi Kurdistan.

Methods

In this retrospective analysis, a total of 200 patients who were diagnosed with obstructive hydrocephalus and underwent ETV and EVD utilizing a modified entry site were included. The revised Kocher point was located 11.5 cm posterior and superior to the nasion, 3 cm laterally, and 0-1 cm before the coronal suture.

Results

The use of this modified Kocher's point has brought much improvement in surgical precision and safety. This would minimize incidences of bleeding and misplacement of the catheters. The anatomical structure was well organized, and nothing was challenging in the process of traversing through the foramen of Monro into the third ventricle. It was easily introduced through the modified Kocher point with increasing efficacy and near zero possibility of sustaining injury to the limiting cerebral region.

Conclusion

Using the modified point of Kocher provides added reliability and accuracy to ventriculostomy, thereby reducing complications and increasing the overall outcome of surgeries. It overcomes all the drawbacks of classical entry sites and, further, helps in increasing the productivity of ETV and EVD. More research must be done to support the benefits of this modification in other clinical settings.

Management and safety of intraoperative ventriculostomy during early surgery for ruptured intracranial aneurysms

BACKGROUND

Brain edema and/or acute hydrocephalus are common features that limit working space during early surgery of aneurysmal subarachnoid hemorrhage (aSAH). Intraoperative ventriculostomy offers an immediate brain relaxation. However, management and complications related to the routine use of intraoperative external ventricular drainage (iEVD) are not well investigated.

METHODS

We retrospectively reviewed all patients who were treated with pterional craniotomy and clipping for ruptured anterior circulation aneurysms in our center between 2012 and 2019. We included in this study all patients submitted to iEVD using the Paine's point on the side of craniotomy. Indication for positioning of an iEVD was given in all cases whenever initial cisternal dissection was hampered by the lack of cerebrospinal fluid (CSF) circulation due to SAH and/or hydrocephalus.

RESULTS

In the study period, 162 patients with aSAH underwent surgical clipping. In 103 patients, an iEVD was used. The overall rate of iEVD-related complications was 6.7%, including 3 cases of catheter misplacement, one case of catheter obstruction, one case of related hemorrhage, and 2 cases of infection. The rate of shunt-dependent hydrocephalus was 16.5% (17/103 patients).

CONCLUSION

In our experience, iEVD is a safe technique that facilitates dissection during early surgery for intracranial ruptured aneurysms, without requiring an additional burr hole procedure.

Predictors of ventriculostomy-associated infections: A retrospective study of 243 patients

OBJECTIVE

Risk factors of ventriculostomy-associated infection (VAI) reported in the literature are variable due to heterogeneity of external ventricular drainage (EVD) procedures and management. This study aimed to assess the rate of VAI and its risk factors.

METHODS

The authors retrospectively reviewed the medical records of patients older than 18 years who received EVD catheterizations between January 2015 and December 2020.

RESULTS

Among 243 patients with 355 catheters, twenty-three VAIs were identified, yielding VIA rates of 9.5% per patient and 6.5% per catheter. VAI was associated with a longer total EVD duration (29.2 days vs. 15.8 days, P < 0.001), a longer procedural time (72 minutes vs. 40 minutes, P < 0.001), intraoperative ventriculostomy (39.1% vs. 9.1%, P < 0.001), craniotomy (87.0% vs. 60.9%, P = 0.014), and other systemic infections (30.4% vs. 8.2%, P = 0.004). On multivariate analysis, a longer total EVD duration (OR = 1.086, P < 0.001), intraoperative ventriculostomy (OR = 6.119, P = 0.001), and other systemic infections (OR = 4.620, P = 0.015) were associated with VAI. There was no statistical difference between the VAI rates of patients with and without prophylactic EVD exchanges at mean 12.6 days (7.1% vs. 2.2%, P = 0.401).

CONCLUSIONS

Intraoperative ventriculostomy was independently associated with VAI. Prophylactic EVD exchange at 12.6 days did not lower VAI rate.

White Matter Governed Superior Frontal Sulcus Surgical Paradigm: A Radioanatomic Microsurgical Study-Part II

BACKGROUND

Kocher's point (KP) and its variations have provided standard access to the frontal horn (FH) for over a century. Anatomic understanding of white matter tracts (WMTs) has evolved, now positioning us to better inform the optimal FH trajectory.

OBJECTIVE

To (1) undertake a literature review analyzing entry points (EPs) to the FH; (2) introduce a purpose-built WMT-founded superior frontal sulcus parafascicular (SFSP)-EP also referred to as the Kassam-Monroy entry point (KM-EP); and (3) compare KM-EP with KP and variants with respect to WMTs.

METHODS

(1) Literature review (PubMed database, 1892-2018): (a) stratification based on the corridor: i. ventricular catheter; ii. through-channel endoscopic; or iii. portal; (b) substratification based on intent: i. preoperatively planned or ii. intraoperative (postdural opening) for urgent ventricular drainage. (2) Anatomic comparisons of KM-EP, KP, and variants via (a) cadaveric dissections and (b) magnetic resonance-diffusion tensor imaging computational 3D modeling.

RESULTS

A total of 31 studies met inclusion criteria: (a) 9 utilized KP coordinate (1 cm anterior to the coronal suture (y-axis) and 3 cm lateral of the midline (x-axis) approximated by the midpupillary line) and 22 EPs represented variations. All 31 traversed critical subcortical WMTs, specifically the frontal aslant tract, superior longitudinal fasciculus II, and inferior fronto-occipital fasciculus, whereas KM-EP (x = 2.3, y = 3.5) spares these WMTs.

CONCLUSION

KP (x = 3, y = 1) conceived over a century ago, prior to awareness of WMTs, as well as its variants, anatomically place critical WMTs at risk. The KM-EP (x = 2.3, y = 3.5) is purpose built and founded on WMTs, representing anatomically safe access to the FH. Correlative clinical safety, which will be directly proportional to the size of the corridor, is yet to be established in prospective studies.

Intraoperative Temporal Horn Ventriculostomy for Brain Relaxation During Aneurysm Surgeries in Pterional Approaches

BACKGROUND

Achieving optimal brain relaxation is paramount in aneurysm surgery. Despite proper positioning and the use of newer anesthetic drugs and the administration of decongestants, it is often not possible to achieve satisfactory relaxation, which can lead to neurological deficits owing to excessive brain retraction. The present study aimed to provide detailed surgical notes regarding the novel technique of temporal horn tapping for intraoperative ventriculostomy.

METHODS

The hospital records of anterior circulation aneurysm surgery performed during the previous 5 years were retrieved. Only those cases in which we had used temporal horn tapping were included. Ventriculostomy was performed only in those cases in which the brain was tense despite the administration of decongestants. A small corticectomy was performed over the middle temporal gyrus and deepened to access the temporal horn.

RESULTS

This technique was used in 84 surgical cases. The mean patient age was 52.8 years. The male/female ratio was 1:1.4. Anterior communicating artery aneurysms were the most common. Adequate brain relaxation was satisfactorily achieved in all cases. Two patients had developed a small temporal hematoma attributable to the temporal corticectomy, both managed conservatively.

CONCLUSIONS

We believe that this new trajectory through the middle temporal gyrus to access the temporal horn is very safe because of the lack of proximity to any blood vessel or critical structures. We recommend the use of this technique during pterional approaches for acute aneurysmal surgery in the tight, bulging brain to achieve relaxation and avoid secondary complications such as retraction contusions and resultant cerebral edema.

Craniometrics and Ventricular Access: A Review of Kocher's, Kaufman's, Paine's, Menovksy's, Tubbs’, Keen's, Frazier's, Dandy's, and Sanchez's Points

Intraventricular access is frequently required during neurosurgery, and when neuronavigation is unavailable, the neurosurgeon must rely upon craniometrics to achieve successful ventricular cannulation. In this historical review, we summarize the most well-described ventricular access points: Kocher's, Kaufman's, Paine's, Menovksy's, Tubbs’, Keen's, Frazier's, Dandy's, and Sanchez's. Additionally, we provide multiview, 3-dimensional illustrations that provide the reader with a novel understanding of the craniometrics associated with each point.

The ventricular system of the brain: a comprehensive review of its history, anatomy, histology, embryology, and surgical considerations

INTRODUCTION

The cerebral ventricles have been recognized since ancient medical history. Their true function started to be realized more than a thousand years later. Their anatomy and function are extremely important in the neurosurgical panorama.

METHODS

The literature was searched for articles and textbooks of different topics related to the history, anatomy, physiology, histology, embryology and surgical considerations of the brain ventricles.

CONCLUSION

Herein, we summarize the literature about the cerebral ventricular system.

Brain Injuries during Intraoperative Ventriculostomy in the Aneurysmal Subarachnoid Hemorrhage Patients

OBJECTIVE

Intraoperative ventriculostomy is widely adopted to make the slack brain. However, there are few reports about hemorrhagic or parenchymal injuries after ventriculostomy. We tried to analyze and investigate the incidence of these complications in a consecutive series of patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

From September 2006 to June 2007, 43 patients underwent surgical clipping for aneurysmal SAH at our hospital. Among 43 patients, we investigated hemorrhagic or parenchymal injuries after intraoperative ventriculostomy using postoperative computed tomographic scan in 26 patients. After standard pterional craniotomy, ventriculostomy catheter was inserted perpendicular to the cortical surface along the bisectional imaginary line from Paine's point.

RESULTS

Hemorrhagic injuries were detected in 12 of 26 patients (46.2%). Mean systolic blood pressure during anesthesia was with in statistically significant parameter related to hemorrhage (p = 0.006). On the other hand, parenchymal injuries were detected in 11 of 26 patients (42.3%). Female and the amount of infused mannitol during anesthesia showed statistically significant parameters related to parenchymal injury (p = 0.005, 0.04, respectively). However, there were no ventriculostomy-related severe complications.

CONCLUSION

In our series, hemorrhagic or parenchymal injuries after intraoperative ventriculostomy occurred more commonly than previously reported series in aneurysmal SAH patients. Although the clinical outcomes of complications are generally favorable, neurosurgeon must keep in mind the frequent occurrence of brain injury after intraoperative ventriculostomy in the acute stage of aneurysmal SAH.