Severe ventricular thalamic hemorrhage is characterized by acute onset, severe clinical symptoms, thalamic nerve function damage, hemorrhage entry into the ventricle, obstruction of the cerebrospinal fluid circulation, and severe hydrocephalus[6, 12]. The thalamus, fornix, basal ganglia, brainstem, and other important nerve structures are located around the ventricle. Acute intraventricular hemorrhage easily causes damage and extrusion effects of peripheral nerve structure, resulting in secondary damage[2]. Most patients have a severe disturbance of consciousness, and even clinical manifestations, such as pupil enlargement and respiratory circulation failure, the latter of which is life-threatening[8]. The location of the ventricular thalamic hemorrhage is deep and the surrounding structures are important. It is difficult to remove a hematocele from the thalamus and ventricle, relieve the ventricular infarction, and restore the cerebrospinal fluid circulation in a timely fashion[5]. The clinical curative effect is usually poor, and the disability and mortality rates are high. According to the literature, the mortality rate of severe ventricular thalamic hemorrhage is 60%−75%[7].
The key to the clinical treatment of severe ventricular thalamic hemorrhage is to remove the hematocele in the thalamus and ventricle as soon as possible, reduce the intracranial pressure, restore the cerebrospinal fluid circulation, and reduce the secondary damage of important peripheral nerve structures[10, 11]. The traditional surgical treatment for severe ventricular thalamic hemorrhage most often involves simple ventricular puncture and external drainage. This surgical procedure is fast and simple, and has been mastered and adopted by most medical units. Simple ventricular puncture and external drainage has become a common method for the treatment of severe intraventricular thalamic hemorrhage[4]. Continuous drainage of bloody cerebrospinal fluid and lumbar cistern cerebrospinal fluid replacement in the middle and late stage have a positive therapeutic effect on the treatment of severe intraventricular thalamic hemorrhage[20]; however, patients with severe intraventricular hemorrhage have more intraventricular blood clots and intraventricular casting. The drainage tube outside the ventricle is easily obstructed and the drainage does not flow smoothly. It is difficult to remove a large amount of hematocele from the thalamus and ventricle in a short time[22]. It is difficult to relieve the infarction and hematoma compression of the intraventricular system as soon as possible, so the clinical effect is not ideal. In addition, the retention time of the ventricular drainage tube is too long, which increases the risk of intracranial infection[16]. With the development and progress of neuroendoscopy technology, clinical studies have reported that removal of a hematocele in the thalamus and ventricle through neuroendoscopy has achieved gratifying results. By integrating the advantages of modern surgery with high-definition neuroendoscopy, hematocele in the thalamus and ventricle can be removed and smooth cerebrospinal fluid circulation can be restored with minimal invasion, which has become an effective new method for the surgical treatment of severe intraventricular thalamic hemorrhage.
In this study, 41 patients with severe intraventricular thalamic hemorrhage were treated with neuroendoscopic frontal surgery to remove hematocele in the thalamus and ventricle. An Endoport transparent sleeve was inserted during the operation to remove hematocele in thalamus and ventricle under direct vision. By adjusting the insertion direction and depth of the sleeve, the hematocele in the third ventricle is aspirated through the interventricular hole, and the hematocele in the contralateral ventricle is aspirated along the damaged transparent septum, which can clear hematocele in the thalamus and ventricle and restore the cerebrospinal fluid circulation. Within 24 h postoperatively, the hematoma clearance rate reached 83.6%, and had a very good hematoma clearance rate. Forty-two patients with severe intraventricular thalamic hemorrhage were treated by simple extraventricular drainage. The clearance rate 24 h postoperatively was 20.6% as revealed by CT scan. There was a significant difference between the two groups. It has been reported that the effective hematoma clearance rate is 73.8%−93.5%[18 ], which is consistent with the results of this study. Hematocele in the thalamus and ventricle were removed and the cerebrospinal fluid circulation was restored better in the neuroendoscopy group than the simple extraventricular drainage. The intraventricular drainage tube is retained for 3-7 days postoperatively. The retention time was shorter, and the incidence of postoperative hydrocephalus and intracranial infection was significantly reduced. According to the data of this group, the incidence of postoperative hydrocephalus and postoperative intracranial infection was 9.75% and 7.31%, respectively. In the extraventricular drainage group, the drainage tube was retained for a longer time and the hematoma was difficult to be removed in a short time. Some patients required urokinase lavage. The incidence of postoperative hydrocephalus and intracranial infection was higher. The incidence of postoperative intracranial infection was 19.04% and the incidence of hydrocephalus was 40.47%. There were significant differences between the two groups. Kellner et al. compared neuroendoscopic hematoma removal and simple ventricular drainage in the treatment of patients with moderate and severe ventricular thalamic hemorrhage[13]. The former had a shorter drainage tube placement time and lower postoperative hydrocephalus and intracranial infection rate. Neuroendoscopy has many advantages. Neuroendoscopy can provide good lighting during deep operation of brain tissue, a good field of view, and no dead corners. Bleeding points can be found in some patients intraoperatively[19]. In the case of venous bleeding, cotton pieces and hemostatic gauze can be pressed to control bleeding. In case of active arterial bleeding, bipolar electrocoagulation and cauterization can effectively reduce the incidence of postoperative rebleeding. According to the data of this study, the incidence of postoperative rebleeding in the neuroendoscopy group was 9.75%, and the incidence of postoperative rebleeding in the extraventricular drainage group was 11.90%.
In this study, with the improvement in postoperative GCS score and follow-up at 6 months, the improvement in postoperative GCS and ADL scores in the neuroendoscopy group were significantly better than the simple extraventricular drainage group. Neuroendoscopic treatment of patients with severe intraventricular thalamus hemorrhage can improve the prognosis and the quality of life, and reduce the mortality. Neuroendoscopic treatment can effectively clear a hematocele from the thalamus and ventricle, reduce intracranial pressure, restore the cerebrospinal fluid circulation, reduce secondary nerve injury, and effectively reduce the incidence of postoperative hydrocephalus and intracranial infection.
With good illumination, neuroendoscopy can be performed under direct vision to remove a hematocele from the thalamus and ventricle[1]. The choice of the surgical approach is very important. The common approaches reported in the literature include the transtriangular, transfrontal, and transoccipital approaches[21]. It is difficult to remove a hematoma in the anterior horn of the lateral ventricle through the triangular and occipital approaches, which cannot unblock the interventricular foramen effectively, the lateral or prone position is often required, and the placement of the body position is time-consuming and cumbersome. In this study, the middle frontal gyrus approach through the Kocher point was used, and the Endoport endoscopic sleeve was inserted, which can better enter the ventricle for endoscopic procedures. The middle frontal gyrus is a non-functional area with few blood vessels. The operation had little damage to nerve function, which was easy to master and in line with the concept of micro-invasion.
During endoscopic surgery, we should be familiar with the anatomy of the ventricle and surrounding structures[3]. First, the ventricular wall should be identified, the orientation determined, and the blood and blood accumulation in the ipsilateral lateral thalamus and contralateral ventricle along the hematoma should be removed to avoid damaging the choroid plexus, collicular vein, and transparent septal vein in the ventricle. Unnecessary damage to important nerve structures, such as the thalamus, fornix, and corpus callosum, should be avoided. For patients with severe casting of hematocele in the fourth ventricle, the effect of supratentorial intraventricular hematoma removal through neuroendoscopy is often poor, and obstruction of the cerebrospinal fluid circulation in the fourth ventricle is difficult to restore. The fourth ventricle hematoma should be removed through the posterior occipital median membrane using the same approach at the same time to restore the cerebrospinal fluid circulation, relieve the compression on the brainstem, and improve the success rate of rescue[17].
In conclusion, it was feasible and effective to treat patients with severe intraventricular thalamus hemorrhage complicated with casting through Kocher point using the middle frontal gyrus approach. Compared with the traditional external drainage of the ventricle, it had a higher hematoma clearance rate, fewer intracranial infections and hydrocephalus. It could improve the prognosis of the patients, which was suitable for clinical use.