Through the choroidal fissure: a quantitative anatomic comparison of 2 incisions and trajectories (transsylvian transchoroidal and lateral transtemporal)

Choroidal fissure and choroidal fissure cysts: a comprehensive review

In this paper, the authors discuss the embryology and anatomy of the choroidal fissure, as well as the pathophysiology and treatment of cerebrospinal fluid cysts of this structure. Understanding its anatomical relations to nearby structures plays an essential role during brain surgeries. With the advancement and availability of imaging techniques, lesions of the choroidal fissure are often found incidentally. Patients are usually asymptomatic or exhibit symptoms that do not correlate with anatomical location or do not require surgical treatment. The choroidal fissure is a key landmark used during brain surgery. Therefore, a comprehensive understanding of it and nearby anatomical structures is essential. Choroidal fissure cysts can be found incidentally, and well-known key features will allow one to differentiate them from other lesions. Surgical treatment should be reserved for symptomatic patients while asymptomatic patients should be monitored.

Progressive Deconstruction of a Distal Posterior Cerebral Artery Aneurysm Using Competitive Flow Diversion

Progressive deconstruction is an endovascular technique for aneurysm treatment that utilizes flow diverting stents to promote progressive thrombosis by diverting blood flow away from the aneurysm's parent vessel. While the aneurysm thromboses, collateral blood vessels develop over time to avoid infarction that can often accompany acute parent vessel occlusion. We report a 37-year-old woman with a left distal posterior cerebral artery aneurysm that was successfully treated with this strategy. The concept and rationale of progressive deconstruction are discussed in detail.

Quantification and comparison of neurosurgical approaches in the preclinical setting: literature review

There is a growing awareness of the need for evidence-based surgery and of the issues that are specific to research in surgery. Well-conducted anatomical studies can represent the first, preclinical step for evidence-based surgical innovation and evaluation. In the last two decades, various reports have quantified and compared neurosurgical approaches in the anatomy laboratory using different methods and technology. The aim of this study was to critically review these papers. A PubMed and Scopus search was performed to select articles that quantified and compared different neurosurgical approaches in the preclinical setting. The basic characteristics that anatomically define a surgical approach were defined. Each study was analyzed for measured features and quantification method and technique. Ninety-nine papers, published from 1990 to 2013, were included in this review. A heterogeneous use of terms to define the features of a surgical approach was evident. Different methods to study these features have been reported; they are generally based on quantification of distances, angles, and areas. Measuring tools have evolved from the simple ruler to frameless stereotactic devices. The reported methods have each specific advantages and limits; a common limitation is the lack of 3D visualization and surgical volume quantification. There is a need for a uniform nomenclature in anatomical studies. Frameless stereotactic devices provide a powerful tool for anatomical studies. Volume quantification and 3D visualization of the surgical approach is not provided with most available methods.

Microsurgical anatomy of the transsylvian translimen insula approach to the mediobasal temporal lobe: Technical considerations and case illustration

Background:

Various vascular, neoplastic, and epileptogenic pathologies occur in the mediobasal temporal region. A transsylvian translimen insula (TTI) approach can be used as an alternative to temporal transcortical approach to the mediobasal temporal region. The aim of this study was to demonstrate the surgical anatomy of the TTI approach, including the gyral, sulcal, and vascular anatomy in and around the limen insula. The use of this approach is illustrated in the resection of a complex arteriovenous malformation.

Methods:

The TTI approach to the mediobasal temporal region was performed on three silicone-injected cadaveric heads. The gyral, sulcal, and arterial anatomy of the limen insula was studied in six formalin-fixed injected hemispheres.

Results:

The TTI approach provided access to the anterior and middle segments of the mediobasal temporal lobe region as well as allowing access to temporal horn of the lateral ventricle. Using this approach we were able to successfully resect an arteriovenous malformation of the dominant medial temporal lobe.

Conclusion:

The TTI approach provides a viable surgical route to the region of mediobasal temporal lobe region. This approach offers an advantage over the temporal transcortical route in that there is less risk of damage to optic radiations and speech area in the dominant hemisphere.

Simultaneous posterior communicating artery aneurysm clipping and selective amygdalohippocampectomy via direct lateral access through the mesial temporal lobe to the basal cisterns

We report a 23-year-old man with intractable epilepsy and an incidental posterior communicating artery aneurysm who was treated simultaneously for both pathologies. He was counseled regarding the potential to treat both pathologies with one procedure. He elected to undergo a simultaneous approach. The patient was doing well at his 5-month follow-up examination with no residual seizures or neurologic deficits. We conclude that access to aneurysms within the basal cisterns is viable with transchoroidal approaches through the temporal horn of the lateral ventricle. Anterior extension through portions of the amygdala further increases access. In our patient, selective amygdalohippocampectomy and posterior communicating artery aneurysm clipping were performed during the same surgical setting/approach. This directly lateral corridor allowed our young patient with an incidental aneurysm to undergo a less invasive combined operation rather than two separate procedures.