Endoscopic Strategy in Surgical Treatment of Adult Idiopathic Bilateral Occlusion of the Foramen of Monro and Review of the Literature

Adult idiopathic bilateral occlusion of foramen of Monro: Systematic review with illustrative case

BACKGROUND

Adult idiopathic occlusion of foramen of Monro (AIOFM) is a rare condition that results in hydrocephalus, and bilateral presentation is even rarer. Here we report a case of idiopathic bilateral stenosis of the foramen of Monro in an adult patient and performed a systematic literature review on the current treatment options and outcomes.

METHODS

We performed a systematic review of SCOPUS, Science Direct, and PubMed databases in accordance with PRISMA guidelines. Data on demographics, clinical presentation, imaging findings, type of AIOFM, treatment, and outcomes were collected.

RESULTS

A total of 22 cases of bilateral AIOFM were identified in the literature, including ours. The median age was 38.5 years (range: 20-53), with no sex predilection. The most common presenting symptoms were headache (n=16, 73%) and vomiting (n=10, 45%). There were 9 cases of Type 1 AIOFM (stenosis) and 13 cases of Type 2 (membrane occlusion). Majority of patients underwent surgical treatment, mostly endoscopic unilateral foraminoplasty and septostomy (59%), followed by ventriculoperitoneal shunt insertion (31%). One patient underwent medical management only to alleviate her presenting symptoms (seizures). The overall outcome was good for majority of patients at a median follow-up of 6 months.

CONCLUSION

Bilateral AIOFM is a rare condition that may easily be missed, so neurosurgeons should be cognizant of this disease entity. Identification of the type of AIOFM may guide surgical decision-making. Treatment options include neuroendoscopic procedures such as septostomy and foraminoplasty, and ventriculoperitoneal shunt insertion.

Neuroendoscopic access to the third ventricle in patients with narrow foramen of monro without stenosis/obstruction: role of foraminoplasty

OBJECT

One of the critical steps for the success of intraventricular neuroendoscopic procedures is the entry into the third ventricle and passage of the endoscopy system through the foramen of Monro (FM). A diameter larger than that of the instrument used is considered a prerequisite for safely performing the technique, as damage to this structure can lead to alterations in the fornix and vascular structures. When the foramen diameter is narrow and there is no obstruction/stenosis, the role of foraminoplasty in reducing the risk of complications has not been adequately assessed in the literature.

METHODS

A review of endoscopic procedures conducted at our center since 2018 was undertaken. Cases in which preoperative imaging indicated a FM diameter < 6 mm and foraminoplasty technique was applied were examined to determine the technical and functional success of the procedure. The technical success was determined by completing the neuroendoscopic procedure with the absence of macroscopic lesions in the various structures comprising the foramen and without complications in the follow-up imaging tests. Functional success was defined as the absence of cognitive/memory alterations during the 3-month postoperative follow-up. Additionally, a review of the various forms of foraminoplasty described in the literature is conducted.

RESULTS

In our cohort, six patients were identified with a preoperative FM diameter < 6 mm without obstruction or stenosis. Foraminoplasty was planned for these cases to facilitate various intraventricular neuroendoscopic procedures. In all instances, the technique was successfully performed without causing macroscopic damage to the structures comprising the foramen. Follow-up visits included various cognitive tests to assess potential sequelae related to microscopic damage to the fornix. None of the patients exhibited anomalies.

CONCLUSION

Foraminoplasty in patients with a narrow FM without signs of stenosis/obstruction is a useful technique to reduce the risk of complications during the passage of the endoscopy system through this structure, enabling the safe performance of neuroendoscopic procedures.

Case Report: Occlusion of the foramen of Monro treated with endoscopic septostomy and foraminotomy in a preterm neonate

Background

Hydrocephalus is a brain abnormality frequently encountered in neonates. There are several known etiologies of hydrocephalus, which can be classified as either congenital or acquired. Occlusion of the foramen of Monro (FOM) is a cause of hydrocephalus and can be either congenital or secondary to various disorders. Idiopathic obstruction of the FOM presenting as prenatal ventriculomegaly is extremely rare but has been reported.

Case presentation

We present the case of a preterm newborn with severe bilateral hydrocephalus due to FOM occlusion in the prenatal period. Although the neonate had normal head circumference and no clinical symptoms after birth, brain sonography revealed progressive ventriculomegaly. Further image revealed bilateral ventriculomegaly with normal-sized third and fourth ventricles. We suspected a complete obstruction of the right and a partial obstruction of the left of the FOM. The neonate underwent endoscopic septostomy and foraminotomy, resulting in improvement.

Conclusion

We report a case of preterm FOM occlusion in the youngest and smallest neonate to date. Endoscopic septostomy and foraminotomy were performed in order to avoid ventriculoperitoneal shunt-related complications, highlighting the viability of endoscopic procedures which should be the primary treatment in preterm neonates with FOM occlusion.

Idiopathic bilateral occlusion of Foramen of Monro treated by septostomy with unilateral foraminoplasty: a rare case report

Introduction

Idiopathic occlusion of the Foramen of Monro is extremely rare in adults. The occlusion is classified into four types, with the first being the most infrequent. This condition induces noncommunicating hydrocephalus with the ensuing increased intracranial pressure symptoms. Headache is usually the chief complaint.

Presentation of the case

The authors present a case of a 28-year-old female who presented with a chronic headache that was unresponsive to analgesics. No other neurological deficits were present. Fundoscopic examination revealed the presence of bilateral papillary edema. Computed tomography scan results showed bilateral enlargement of the lateral ventricles of the brain. A subsequent MRI scan ruled out secondary causes of occlusion, such as colloid cysts, meningiomas, or choroid plexus tumors, which entailed an idiopathic etiology.Treatment options include ventriculoperitoneal shunt insertion and septostomy with foraminoplasty. The former option is currently the treatment of choice, yet it is notorious for its ramifications, including foreign body reaction, breakage, and mechanical problems. The latter option is free of these risks; however, it requires meticulousness and precision to avoid damaging the fornix, which leads to impaired memory function.

Conclusion

Septostomy with unilateral foraminoplasty could yield better outcomes if it is performed fastidiously.

Late-onset occlusion of the Monro foramina after endoscopic third ventriculostomy in adults: Case discussion and review of the literature

Background:

Few cases of adult idiopathic occlusion of the foramen of Monro (AIOFM) are described in the literature. The diagnosis of AIOFM after an endoscopic procedure is even more infrequent.

Case Description:

We described the case of a 50-year-old woman who developed bilateral membranous occlusion of both Monro foramina 20 years after an endoscopic third ventriculostomy (ETV) for triventricular hydrocephalus due to an aqueductal stenosis. The patient underwent an endoscopic treatment (left foraminoplasty and septostomy) to check the patency of the stoma on the floor of the third ventricle. After the endoscopic procedure, the symptoms improved and the postoperative magnetic resonance imaging (MRI) demonstrated the resolution of the biventricular hydrocephalus.

Conclusion:

Bilateral occlusion of both FM with consequent bilateral lateral ventricles enlargement is an extremely rare condition, especially if we consider the cases of biventricular hydrocephalus after endoscopic procedures. In our opinion, an endoscopic approach should be attempted as first choice procedure, avoiding any intraventricular stent or shunt placement.

Idiopathic stenosis of foramina of Monro in an asymptomatic adult patient: a rare entity radiologists should be aware of

Bilateral Adult Idiopathic Oclussion of Foramen of Monro is a rare entity, with less than 22 cases published in the literature so far, all of them symptomatic.¹ When the symptoms require it, the current first-line treatment is endoscopic foraminoplasty, sometimes associated with septum pellucidum fenestration, although some authors consider that a more conservative treatment in paucisymptomatic patients.² We report the case of an idiopathic biventricular hydrocephalus found incidentally in an asymptomatic 42-year-old female with temporomandibular joint disfunction. The fact that some patients with Monro foraminal stenosis may be asymptomatic increases the possibility of underdiagnosis, so we consider it a condition that radiologists should be aware of, mainly taking into account the fact that the diagnosis of this entity is usually radiologic³ and the potential complications associated with treatment.

Adult bilateral idiopathic occlusion of foramina of Monro: is foraminoplasty really safe and effective?

Idiopathic bilateral occlusion of foramina of Monro is an extremely rare condition in adults and only few cases are reported. Currently, foraminoplasty is indicated as first-line treatment. We reported the case of a 52-year-old woman who presented with headache, instability and urinary incontinence. The imaging demonstrated bilateral occlusion of foramina of Monro and consequent biventricular hydrocephalus. A ventriculo-peritoneal shunt allowed to treat the hydrocephalus, but it was necessary to remove it for the appearance of peritonitis from salpingitis. Since the initial symptomatology reappeared, according to the literature, we performed an endoscopic foraminoplasty with septostomy. The patient immediately developed short-term memory impairment and subsequently we observed the hydrocephalus recurrence. The positioning of a ventriculo-atrial shunt allowed to improve the symptoms, but the memory remained impaired. In case of bilateral true stenosis of foramina of Monro, foraminoplasty may lead to severe memory impairment. Therefore, cerebrospinal fluid shunting should be considered as an effective and safer treatment.