Neurological Surgery最新文献

Meningiomas are the most common brain tumors, often in the form of extra-axial masses adhering to the dura mater. Although there are typical imaging findings, meningiomas have a wide variety of imaging findings, owing to their different histological subtypes. Thus, it can be difficult to differentiate meningiomas from other diseases that present with similar imaging findings. This section outlines mimickers for monitoring meningiomas that present with imaging findings similar to those of meningiomas. Diseases that form masses and require differentiation from meningiomas include schwannomas, solitary fibrous tumors, dural metastases, and histiocytosis. Diseases that primarily present as dural thickening and require differentiation from meningiomas include hypertrophic duralitis, fungal infections, and IG4-related diseases. Notably, in addition to the various pathologies that can mimic meningiomas, such as those listed above, there are also cases in which the diagnosis of meningioma is difficult because of additional modifications, such as metastasis or meningioma infarction.

The efficacy of deep brain stimulation(DBS)for Tourette's syndrome is being well established. Herein, we performed DBS in 38 patients and confirmed that its efficacy was comparable with that reported internationally. Although many patients experience severe symptoms, the indications for surgery remain controversial. One reason for this is that Tourette syndrome has the potential for spontaneous remission, while DBS treatment results in the need for long-term management, which can be difficult for some patients. Furthermore, while several targets for DBS have been reported, no treatment guidelines have yet been established. The efficacy of DBS for neuropsychiatric disorders, such as obsessive-compulsive disorder, depression, and dementia, is gradually being reported. However, this use has many limitations in terms of expectations similar to those seen with Tourette's syndrome, leading to problems with expanding indications for these disorders. Indications for these disorders should be addressed in conjunction with ethical issues. It is expected that more data on this topic will be collected in the future.

In the World Health Organization 2022 classification, a nomenclature change from pituitary adenoma to pituitary neuroendocrine tumor(PitNET)was introduced to indicate rare but potentially malignant behavior. No grading system is available for PitNETs; therefore, the establishment of a system that corresponds to their clinical behavior is an urgent issue. Presently, this change has no direct influence on therapeutic strategies. Recently, the therapeutic outcomes of most patients with PitNETs have significantly improved owing to marked advancements in both surgical and medical treatments. The former includes the evolution of endoscopic surgery and technical refinements, whereas the latter includes the introduction of new effective drugs and increased knowledge and experience regarding their use, leading to personalized and/or precision medicine. Consequently, the treatment goals have advanced, encompassing endocrinological remission, successful management of comorbidities, increased health-related quality of life, and a normalized mortality rate. However, management of some aggressive and metastatic PitNETs remains difficult. Although temozolomide(TMZ)is considered a promising sole therapeutic option, recent reports have shown that TMZ does not provide long-term control in many cases. A multidisciplinary approach is necessary for the reliable prediction and successful management of aggressive tumors.

A right aortic arch and aberrant subclavian artery result from an interruption in the remodeling of the pharyngeal arch arteries. We occasionally encounter this anatomical variation during angiography. Patients with disorders such as Down syndrome and congenital heart disease show a high incidence of an aberrant right subclavian artery, and this anomaly can cause symptomatic esophageal or tracheal compression. The root of the aberrant artery may show dilatation(referred to as a Kommerell diverticulum), dissection, intramural hematoma, or rupture necessitating cardiac intervention using a surgical or endovascular approach. Neurointerventionalists should have working knowledge of the anatomy to rapidly understand the anatomy and ensure a safe procedure. A left transradial approach should be considered if prior knowledge of the aberrant subclavian anatomy is available.

The transverse sinus(TS)and sigmoid sinus(SS)are common sites for dural arteriovenous fistulas, and an understanding of vascular anatomy is important when developing treatment strategies. In recent years, transarterial embolization, with a liquid embolization material, has become the treatment of choice, preserving the sinus without extensive coil filling of the affected sinus. With this expansion of therapeutic options, we feel that an understanding of the microanatomy has become more important. For example, the exact site where the vein of Labbé joins the TS should be determined. This article focuses on the development and anatomy of the TS and SS and makes points that should be considered when treating dural arteriovenous fistulas.

The angioarchitecture of the hindbrain is homologous to that of the spinal cord, and its vascular system can be analyzed at the longitudinal and axial structures. During embryonic development, there are two main longitudinal arteries: the longitudinal neural artery and the primitive lateral basilovertebral anastomosis. Commonly observed variations are formed by the fenestration and duplication of either the vertebrobasilar artery, or cerebellar artery, which can be observed when the primitive lateral basilovertebral anastomosis partially persists. Understanding the pattern and development of blood supply to the hindbrain provides useful information of various anomalies in the vertebrobasilar junction and cerebellar arteries.

Thorough understanding of the vascular anatomy, including embryological development of vessels is important to safely perform endovascular procedures. The posterior cerebral and anterior choroidal arteries are embryologically complementary, which suggests a potential network. Numerous perforators originate from the posterior communicating and posterior cerebral arteries. The tuberothalamic artery arising from the posterior communicating artery and the thalamoperforating artery, which originates from the P1 segment of the posterior cerebral artery are clinically important because occlusion of these vessels can precipitate severe infarction. It is clinically important to be aware that the branching pattern of perforators differs based on the fusion type of the basilar tip. The balloon occlusion and Allcock test are useful to predict ischemic tolerance in cases of intentional artery occlusion. However, accurate prediction remains challenging, and a definitive evaluation method is unavailable. Flow disturbances in the cortical territory and local perforator impairment require close attention in cases of intentional artery occlusion.

This article describes the concept and technical aspects of the occipital transtentorial approach(OTA)for tumor extraction in the pineal region, based on the author's experience and literature review. Awareness of the successful completion of each surgical step is essential. Preoperative preparation and imaging evaluations, with particular attention to the veins and venous sinuses, are especially important. It is also helpful to perform a complete dura incision and inversion up to the edge of confluence, superior sagittal sinus, and transverse sinus. Subsequently, it is necessary to understand the usefulness of adequate dissection in the vicinity of the corpus callosum and internal occipital vein(IOV)so that the occipital lobe can be moved without difficulty. Furthermore, development of the IOV with adequate tentoriotomy facilitates contralateral work. Finally, complete understanding of each step during the bilateral, ambient cistern and cerebellomesencephalic fissure dissection process, where the cerebellar vermis can be moved without difficulty, is necessary for a safe OTA to pineal region tumor extraction.

The basilar artery(BA)is formed by the fusion of two longitudinal arteries, and incomplete development may lead to BA fenestration. The BA provides many short perforating arteries and long lateral pontine arteries to the brain stem. The anterior inferior cerebellar artery(AICA)usually branches from the proximal third of the BA and primarily perfuses the ventral, inferior and lateral aspect of the cerebellum and inner ear organ. However, there are many variations to the AICA that depend on the degree of posterior inferior cerebellar artery development. The superior cerebellar artery(SCA)branches into not only to the rostral, ventral aspect of the cerebellar hemisphere, but also to the deeper cerebellar nucleus and brain stem. Duplications within this vessel are frequently identified, but it is not missing.

The perfusion territory of the external carotid artery is often underestimated; however, this blood vessel forms abundant "dangerous anastomoses" with the internal carotid and vertebral arteries. An understanding of these vascular anastomoses is crucial to ensure safe cerebrovascular interventions. There are several important aspects of the middle meningeal artery that should be considered, including anastomoses with the anterior(frontal)branch and ophthalmic artery through the sphenoidal artery(recurrent meningeal artery)and meningolacrimal artery. Additionally, the blood supply to the facial nerve via branches of the petrosal branch, such as the superior tympanic artery, and the formation of the facial arcade by the superior tympanic and stylomastoid arteries, which often originate from the posterior auricular artery, is significant. The occipital artery demonstrates rich anastomoses with vessels, such as the ascending pharyngeal and vertebral arteries, forming what is known as the pharyngo-occipital system.