Endoscopic ventriculocystocisternostomy of a quadrigeminal cistern arachnoid cyst. Case report.

The authors present the case of an elderly patient with a quadrigeminal arachnoid cyst who was successfully treated with endoscopic fenestration through the posterior wall of the third ventricle via the anterior horn of the lateral ventricle. This 71-year-old man suffered from progressive gait instability and disorientation. Radiological examination revealed hydrocephalus caused by a quadrigeminal arachnoid cyst. The patient underwent endoscopic fenestration of the quadrigeminal cistern arachnoid cyst and third ventriculostomy via one burr hole placed at the coronal suture. This method is less invasive and is effective for quadrigeminal cistern arachnoid cyst and accompanying hydrocephalus.     

Endoscopic treatment of quadrigeminal cistern arachnoid cysts.

Five patients with arachnoid cysts of the quadrigeminal cistern treated by endoscopic fenestration are reported and another eleven well-documented cases from the literature are reviewed. Among the five personal cases four were children and one was adult; the cyst fenestration was performed from the lateral ventricle in three cases and from the third ventricle in two. In four patients the endoscopic treatment resulted in clinical remission, whereas a two-month-old baby later required a shunt. The lateral ventricle-cystostomy and the third ventricle-cystostomy (according to the cyst extent) are the best endoscopic procedures, whereas the cyst fenestration through a suboccipital supracerebellar approach is no longer used. The rate of cured or improved patients after endoscopic surgery (14/16 or 87.5%) was rather similar to that of a group of twenty patients treated by traditional surgery (craniotomy and cyst excision and/or shunt) (85%). These data confirm that endoscopic fenestration of quadrigeminal cistern cysts must be performed as the first procedure because it is less invasive and avoids shunt dependency.     

A case of quadrigeminal cistern arachnoid cyst associated with hydrocephalus

A case of quadrigeminal cistern arachnoid cyst associated with hydrocephalus is reported. A 1-year-old girl was admitted to our service on July 31, 1984, because of mental retardation and an enlarged head. She was born of a full-term pregnancy and normal vaginal delivery without prenatal complications. Progressive increase in her head circumference was noticed at the age of 6 months by her family physician. On admission she was found to be a well-nourished infant with a head circumference of 56 cm, bulging anterior fontanelle and mental retardation. Marked dilatation of the lateral ventricles and a large cyst in the quadrigeminal cistern were demonstrated on plain CT. There were no findings of communication between the ventricular system and the cyst on metrizamide CT ventriculography. The extension of the cyst from the quadrigeminal cistern to the right cerebello-pontine angle was demonstrated on reconstructed coronal CT. Reconstructed sagittal section revealed huge hydrocephalus caused by aqueductal stenosis. A vertebral angiography demonstrated opening of the para-mesencephalic segments of the bilateral posterior cerebral arteries and downward displacement of the right superior cerebellar artery. Accordingly, a large quadrigeminal cistern arachnoid cyst with hydrocephalus caused by aqueductal stenosis was suspected. Following V-P shunt operation for hydrocephalus, right temporo-parietal craniotomy was performed. The inner wall of the lateral ventricle was thin and an expanding cyst was observed through it. A partial resection of the cyst wall with the ventricular wall was performed to obtain communication between the cyst and lateral ventricle. The content of the cyst was watery clear fluid like CSF.(ABSTRACT TRUNCATED AT 250 WORDS)     

A large arachnoid cyst of the lateral ventricle extending from the supracerebellar cistern--case report

BACKGROUND: The pathogenetic mechanism of intraventricular arachnoid cyst development is still controversial, but is believed to originate from the vascular mesenchyme or as an extension of the arachnoid cyst in the subarachnoid space into the ventricle through the choroidal fissure. We report a case supporting the extension hypothesis and suggest differential points between an intraventricular arachnoid cyst that extended from the supracerebellar space and a lateral ventricular diverticulum that extended into the supracerebellar cistern. CASE DESCRIPTION: A 12-month-old girl presented with macrocephaly and developmental delay. Her magnetic resonance imaging showed an arachnoid cyst that had developed from the supracerebellar space in the posterior fossa, and which extended into the left lateral ventricle resulting in expansion of the left lateral ventricle and displacing the choroids plexus anteriorly and laterally and the midline to the right. We treated an intraventricular arachnoid cyst by endoscopic fenestration resulting in dramatic reduction of the intraventricular arachnoid cyst with large bilateral subdural fluid collection. We performed a subduroperitoneal shunt for subdural fluid collection and subsequent cystoperitoneal shunt for the remnant cyst. CONCLUSION: We suggest that this case supports the extension hypothesis from the subarachnoid space through the choroidal fissure into the lateral ventricle. We also suggest that one of the radiological differential points between an intraventricular arachnoid cyst and a ventricular diverticulum is displacement and compression of the choroid plexus of the lateral ventricle.     

Arachnoid cyst of the quadrigeminal cistern

Arachnoid cyst located near the quadrigeminal cistern has been reported as paracollicular arachnoid cyst, arachnoid cyst of the quadrigeminal cistern, paramesencephalic arachnoid cyst, arachnoid cyst posterior to the third ventricle, cyst of the cisterna ambiens. The purpose of this paper is to present the clinical pictures, diagnostic studies and treatment of 5 cases of the arachnoid cyst of the quadrigeminal cistern. (1) The clinical symptoms and signs result from increased intracranial pressure without lateralizing signs (mid-line syndrome) due to hydrocephalus, precocious puberty and supra-collicular sign due to direct compression of the adjacent structures. (2) Endocrinological study of the pituitary gland shows no abnormal findings, but the patients with precocious puberty shows adult type response in LH and FSH. (3) Metrizamide CT cisternography could be considered as a safe and reliable neurological procedures in evaluating the communication between the cyst and the subarachnoid space as well as CSF dynamics, and subarachnoid space. (4) Patients were treated with ventriculoperitoneal shunt, followed by craniotomy and resection of the cyst wall with good results.     

Endoscopic surgery for large posterior fossa arachnoid cysts.

The authors report two cases of large arachnoid cysts of the posterior fossa treated by endoscopic surgery. One patient underwent a successful endoscopic cyst fenestration by burr hole approach after several procedures of shunt revision. In another an endoscope-assisted microsurgical intervention was necessary. Lateral (cerebellar or cerebellopontine angle) cysts, as two reported cases, may be treated through a lateral retromastoid approach by fenestration into the prepontine cistern and eventually into the cisterna magna. We advise to start the operation through a burr hole and to try to realize the fenestration by endoscopy only. If this attempt fails, an endoscope-assisted microsurgical technique may be performed by enlarging the craniectomy. In this last instance the endoscope is useful particularly deeply to fenestrate the anterior cyst wall in the prepontine or ambient cisterns, where it provides more illumination and helps to identify the nervous and vascular structures.     

神经内窥镜临床应用的初步经验：附19例报告

近年来，神经内窥镜在临床已广泛使用。作者应用神经内窥镜清除基底节血肿１０例，皮层下血肿６例，行脑室内、脑室旁和颞叶表面蛛网膜囊肿造瘘术各１例。颅骨钻孔位置选择距病灶最近，并可贯穿病变全程。１０例基底节血肿清除和１例脑室内蛛网膜囊肿造瘘术通过ＣＴ立体定向导入内窥镜，其余病例均徒手导入内镜。有１１例血肿患者术后４８小时以内行ＣＴ复查，９例残余血肿２０％～３０％以下。３例蛛网膜囊肿患者术后症状有所缓解，２例术后１个月ＣＴ复查造瘘口清晰可见，１例体积缩小２０％～３０％。本组病例中无手术直接并发症，体现了内窥镜手术侵袭性小的优点。作者还就内镜术的麻醉选择、操作细节问题进行了详细的讨论。     

Neuroendoscopically assisted cyst-cisternal shunting for a quadrigeminal arachnoid cyst causing typical trigeminal neuralgia.

A quadrigeminal cistern arachnoid cyst is a very rare cause of typical trigeminal neuralgia. A 62-year-old woman presented with right facial pain of 8 years duration. Neuroradiological findings revealed a cystic mass in the quadrigeminal region that compressed the cerebellum downward and the brainstem anteriorly and was associated with hydrocephalus. She had neuroendoscopically-assisted cyst-cisternal shunting via a small craniotomy. Postoperatively, the trigeminal neuralgia disappeared. The origin of the trigeminal neuralgia may have either been a marked distortion of the pons that caused stretching of the trigeminal nerve and irregular demyelination within the root entry zone, or there was contact between the root entry zone and a vascular structure. Neuroendoscopy is useful for treating arachnoid cysts; however, in order to safely relieve symptoms, the procedure needs to be appropriately adapted depending on the pathogenesis. In this paper, we review the literature and discuss the pathophysiology and treatment of our case.     

Arachnoid cyst in the quadrigeminal cistern

Two cases of arachnoid cysts in the quadrigeminal cistern are presented, and one occurred in an adult. Signs and symptoms of increased intracranial pressure were noted, and obstructive hydrocephalus was shown by computed tomography scans in both cases. Arachnoid cysts in the quadrigeminal cistern have rarely been reported, especially in adults. The definition, classification, and etiology of arachnoid cyst are still confused in the literature, and various terms have also been used to indicate this particular location of cyst. In this study, these confusing problems are reviewed, and the usefulness of metrizamide computed tomographic cisternography is emphasized as a noninvasive method of diagnosis.     

Endoscopic ventriculocystostomy through the septum pellucidum via the contralateral anterior horn--technical note

Paraventricular fluid cysts have recently been treated by endoscopic fenestration performed from the cysts to the ventricular system. However, correct orientation and safe navigation of the endoscope may be difficult in patients with abnormal anatomy. Endoscopic fenestration from the ventricular system to a cyst was performed through penetration of the septum pellucidum via the anterior horn of the contralateral lateral ventricle. The advantage of this approach is correct orientation and introduction of the endoscope to the periventricular lesion because the usual landmarks can be identified in the normal contralateral lateral ventricle.     

Controversies in the management of spontaneous cerebellar haemorrhage a consecutive series of 49 cases and review of the literature

Summary We have reviewed our experience with a series of 49 consecutive patients with spontaneous cerebellar haematoma, treated according to a standardized management protocol. Seventeen patients were managed conservatively, 30 underwent ventricular drainage, and in six patients the haematoma was evacuated. The indications for the different modes of treatment are discussed. The most significant prognostic factors determining the outcome at one month were the grade of quadrigeminal cistern obliteration on the initial CT scan and the Glasgow Coma Scale on admission. Patients with normal cisterns had a good outcome, and only needed (temporary) ventricular drainage in case of hydrocephalus. Patients with totally obliterated cisterns had a bad outcome irrespective of treatment. In the patients with compressed cisterns, it is suggested that evacuation of the haematoma might improve outcome; treatment of hydrocephalus alone is insufficient in many cases in this group.     

Infratentorial supracerebellar approach to the colloid cysts of the third ventricle

OBJECTIVE: The transcallosal and the frontal transcortical approaches are the most widely used methods in surgery of third ventricle colloid cysts. However, these approaches require traction of the frontal lobe and dissection of the corpus callosum or corticotomy and involve some postoperative consequences. The rationale of the proposed method is to remove the colloid cyst by the infratentorial supracerebellar approach and the posterior wall of the third ventricle without dissection of any neural structures. METHODS: Five patients with a colloid cyst of the third ventricle were operated on by the proposed method. The first patient presented with several months' history of symptoms that included increased intracranial pressure and right-sided cerebellar signs, caused by a metastatic tumor of the right cerebellar hemisphere. The other four patients had symptoms including intracranial hypertension for an extended period of time without any other neurological deficits. In all patients, magnetic resonance imaging revealed a colloid cyst of the third ventricle without hydrocephalus. TECHNIQUE: With the infratentorial supracerebellar approach, the arachnoid of the quadrigeminal cistern is dissected. The pineal body is separated and displaced from the internal vein medially, and the posterior velum interpositum is opened. Perforation of the inferior layer of the tela choroidea just above the suprapineal recess allows opening of the third ventricle cavity. A foraminal region is exposed after a slight lateral displacement of medial surfaces of the thalamus along the third ventricle roof. CONCLUSION: The proposed approach through the infratentorial supracerebellar space and the posterior wall of the third ventricle may be used for removal of colloid cysts, especially in patients in whom the lateral ventricles are not enlarged.     

Tectal plate cyst in adults

Summary Tectal plate cysts are very rare. We report two adult patients with benign tectal plate cyst and secondary hydrocephalus. The first patient had an unusual eye movement disorder with bilateral upper eyelid retraction (Collier’s sign), limited upgaze, severe upgaze evoked nystagmus and retraction nystagmus. The second patient presented with ataxia and failure of upward gaze. Endoscopic fenestration of the tectal plate cyst and endoscopic third ventriculostomy in both cases result in neurological improvement. To the best of our knowledge, similar lesions at this site have not been reported in adults. The differential diagnosis with arachnoid cysts of the quadrigeminal CSF cistern is discussed.     

Arachnoid cyst in the region of the fourth ventricle mimicking clinical picture of normal pressure hydrocephalus

Arachnoid cysts in the region of the fourth ventricle are rarely reported. Two cases with intraventricular arachnoid cysts (one in the fourth and one in the right lateral) manifesting normal pressure hydrocephalus have been described in the previous literature. Here we report a clinically similar case in which the cyst was wedged in cerebellar vermis and compressed the fourth ventricle. Slow enlargement of the cyst could explain the clinical picture. The removal of the cyst resulted in a marked improvement of the symptoms despite the lack of significant changes in ventricular size.     

Microsurgical anatomy of the choroidal fissure

The microsurgical anatomy of the choroidal fissure was examined in 25 cadaveric heads. The choroidal fissure, the site of attachment of the choroid plexus in the lateral ventricle, is located between the fornix and thalamus in the medial part of the lateral ventricle. The choroidal fissure is divided into three parts: (a) a body portion situated in the body of the lateral ventricle between the body of the fornix and the thalamus, (b) an atrial part located in the atrium of the lateral ventricle between the crus of the fornix and the pulvinar, and (c) a temporal part situated in the temporal horn between the fimbria of the fornix and the lower surface of the thalamus. The three parts of the fissure are the thinnest sites in the wall of the lateral ventricle bordering the basal cisterns and the roof of the third ventricle. Opening through the body portion of the choroidal fissure from the lateral ventricle exposes the velum interpositum and third ventricle. Opening through the temporal portion of the choroidal fissure from the temporal horn exposes the structures in the ambient and crural cisterns. Opening through the atrial portion of the fissure from the atrium exposes the quadrigeminal cistern, the pineal region, and the posterior portion of the ambient cistern. The neural, arterial, and venous relationships of each part of the fissure are reviewed. The operative approaches directed through each part of the fissure are also reviewed.     

Ventricular diverticula in obstructive hydrocephalus secondary to tumor growth

OBJECTIVE: The association of ventricular diverticula with intra- and paraventricular tumors causing obstructive hydrocephalus has rarely been reported. METHODS: Records and imaging findings for 57 patients with obstructive hydrocephalus caused by tumors who were treated at our institution were reviewed for the presence of ventricular diverticula. For the anatomic study of ventricular diverticula, data were collected from five cadaveric heads. RESULTS: Ventricular diverticula were identified on magnetic resonance imaging scans in five cases. Diverticula were similarly located in the quadrigeminal cistern but originated from the medial wall of the atrium of the lateral ventricle in three cases and from the superior portion of the fourth ventricle in two cases. Regression of diverticula occurred in all cases after either insertion of a shunt or removal of the obstructing tumor. The cadaveric study suggested that the choroidal fissure and the rostral portion of the superior medullary velum might be the origins of diverticula from the atrium and from the superior portion of the fourth ventricle, respectively. CONCLUSION: Ventricular diverticula should be distinguished from other cystic lesions in the quadrigeminal region. Detection of an ostium of a diverticulum or communication between the cyst and the ventricular system is important for diagnosis.     

Unusual intraventricular herniation of the suprasellar arachnoid cyst and its successful endoscopic management.

A child with a benign intrinsic tectal tumor and obstructive hydrocephalus developed a huge intraventricular cystic lesion following insertion of a shunt, which was complicated by a subdural-subarachnoid bleeding. The lesion was identified to be an entrapped chiasmatic cistern, which disrupted the septum pellucidum in front of the third ventricle and filled gradually the anterior horn of the lateral ventricle. The condition was successfully treated endoscopically by fenestration of the cyst and a third ventriculostomy. Probable mechanisms of such unusual cyst formation and general management strategies in patients with obstructive hydrocephalus are discussed.     

Endoscopic evacuation of intraventricular hematoma and third ventriculostomy

We described our experience of three cases treated with endoscopic evacuation of intraventricular hematoma and third ventriculostomy for a tight intraventricular hematoma associated with intracerebral hemorrhage. A steerable endoscope was introduced into the anterior horn of the lateral ventricle contralaterally to the intracerebral hemorrhage, through a 14 Fr. peel-away sheath. First, the hematoma in the lateral ventricle contralateral to the hemorrhage was evacuated by direct aspiration using a syringe connected to the operative channel of the endoscope, and evacuation of the hematoma was subsequently carried on the third ventricle, aqueduct and the fourth ventricle. After the evacuation of the intraventricular hematoma, third ventriculostomy was performed for acute obstructive hydrocephalus. Finally, the procedure was completed with septostomy and evacuation of the hematoma in the lateral ventricle ipsilateral to the hemorrhage. Sufficient evacuation of the hematoma was obtained in all cases and no major complications were encountered. We conclude that for patients with intraventricular hematoma associated with intracerebral hemorrhage endoscopic evacuation of intraventricular hematoma brings about sufficient removal of hematoma, reduction of hospitalization time and prevention of subsequent hydrocephalus.     

Primary cerebellar hemorrhage. Quadrigeminal cistern obliteration on CT scans as a predictor of outcome

The authors studied a consecutive series of 75 patients with cerebellar hemorrhage diagnosed by computerized tomography (CT) scanning, and assessed the relationship of outcome to the CT appearance of the quadrigeminal cistern, which in some cases was obliterated by rostral displacement of the vermis resulting from the cerebellar mass. Obliteration of the quadrigeminal cisterns was classified on the CT scans into three grades: normal (Grade I), compressed (Grade II), or absent (Grade III). There were 43 patients with Grade I, 16 with Grade II, and 16 with Grade III cisterns. Of the 75 patients, 38 (88.4%) of those with Grade I, 11 (68.8%) of those with Grade II, and none of those with Grade III cisterns returned to their previous activities at 6 months or more after onset. A Grade I cistern predicted a good outcome whether the hematoma was evacuated or not, as long as obstructive hydrocephalus, if present, was relieved early. However, a Grade II cistern was not predictive of a good outcome unless the hematoma was evacuated within 48 hours after onset of the hemorrhage. A Grade III cistern invariably predicted an unfavorable outcome. It is concluded that the CT grade of quadrigeminal cistern obliteration is an accurate indicator of outcome and is highly useful in selecting appropriate treatment for patients with cerebellar hemorrhage.     

Endoscopic treatment of intracranial lesions. Apropos of 8 cases

The authors describe their initial experience involving endoscopic techniques used in the treatment of eight patients with varied brain lesions. Two tumours and a colloid cyst of the third ventricle, two paraventricular symptomatic cysts, one arachnoid cyst, one chronic intracerebral hematoma and one case of free catheter extraction in the lateral ventricle. The common characteristics of all these lesions were their liquid character and/or intraventricular location. Rigid endoscopes were used, with 9 and 6 mm work channels and independent aspiration and irrigation systems. The optic elbow makes direct visualization and adaptation to the TV monitor possible. The endoscope was manually directed at the lesion through a 12 mm burr hole in five cases and by means of a stereotactic frame in three cases. Biopsies were obtained in six cases. In three cases a communication between the cyst and the ventricular system or adjacent cisterns was established and in two cases vaporization of the lesion using a CO2 laser was performed. Tolerance to the endoscopic procedures was good in all cases. In the authors' opinion, endoscopic techniques constitute a low risk method, midway between stereotactic techniques and the microsurgical approach, and are especially indicated in the treatment of cystic brain lesions or those situated in or near the ventricular system. Their most notable advantages are: providing direct visualization of the lesion without interference from the instruments in the operating field; non-repercussion of the spatial changes derived from the liquid outlet and possibility of lesion coagulation and manipulation. Their disadvantages, related to the use of very long instruments and from a reduced work channel, must be overcome by specialized training.