Endoscopic and Microsurgical Treatment of Sylvian Fissure Arachnoid Cysts—Clinical and Radiological Outcome

Early clinico-radiological outcomes following neuroendoscopic cysto-cisternostomy for middle cranial fossa arachnoid cysts: a prospective cohort study with illustrative cases

BACKGROUND

The dysmorphogenetic arachnoid cysts' pathomechanism is most favoured, and about 50% occur as middle cranial fossa cysts (MCFAC). Still being rare, management options are yet evolving. We described the clinico-radiological features, management and early outcomes of participants with MCFAC in our service.

METHODS

This prospective cohort study involved 29 pediatric participants recruited (from electronic health records, using ICD G93.0 D016080 for arachnoid cysts) between 01/01/2023 and 31/06/2023, following informed consent according to the ethical approval. All participants had neuro-imaging confirmed MCFAC. Baseline and follow-up data were retrieved and analyzed using summary (mean, standard deviation) and inferential (ANOVA, t-test) statistics.

RESULTS

They were averagely aged 6.2 ± 4.48 years and were mostly males (89.7%). 24.1% were asymptomatic. The commonest symptoms (n = 38) were headaches (23.7%), developmental delays (15.8%), eye complaints (15.8%) and cephalomegaly (7.9%). They were predominantly left-sided (89.7%). Galassi (G) 3 lesions were less (24.1%), with G2 and G1 lesions evenly sharing the rest. The average cyst volume was 58.4 ± 80.83cm3; there were significant differences (F = 4.682; p = 0.018) between the average volumes for G1 (14.4 ± 22.42cm3), G2 (61.7 ± 89.92cm3) and G3 (122.5 ± 94.37cm3) lesions. 44.8% of the participants had rigid-endoscopic cysto-cisternotomy (all between the ICA and oculomotor nerve into the interpeduncular cistern, using ventriculostomy forceps); including all G3, 50% of G2 and no G1 (had serial clinico-radiological observation) lesion. The average pre- (117.42cm3) and post-operative (53.48cm3) cyst volumes showed significant (t = - 2.797, p = 0.021) reductions.

CONCLUSION

Middle cranial fossa arachnoid cysts occur predominantly amongst males, in middle childhood and left-sided. The treatment-related patient series are largely symptomatic, unlike the largely asymptomatic, screening-related series. Higher Galassi grade lesions presented with progressively, significantly larger cyst volumes and higher likelihoods of surgery. The average post-operative cyst volume at follow-up averagely showed almost 60% reduction from the pre-operative. All participants reported clinical remission.

Purely Endoscopic Treatment for Arachnoid Cysts

Arachnoid cysts are benign, mostly congenital lesions that are asymptomatic in most patients. In some cases, due to their location or sheer size, they produce a mass effect or hydrocephalic obstruction of the cerebrospinal fluid (CSF) flow and thus might warrant surgical treatment. The goal of the surgery is usually to reduce pressure inside the cysts, to reduce the mass effect, or to restore the CSF pathway. Surgical treatment options are resection, fenestration, or shunting of the cyst. Over the past decades, treatment under sheer endoscopic control either through a tube or via craniotomy of arachnoid cysts has been studied thoroughly and replaced open microsurgical cyst surgery in the opinion of many neurosurgeons. Endoscopic treatment has proven to be a safe and feasible technique for both patients and surgeons. In the following chapter, the authors describe their indications for surgery and pre- and postoperative workup, where precautions should be taken, and discuss the different possibilities and techniques of endoscopic cyst fenestration. The aim is to give detailed instructions and present cases for ventriculocystostomy, cystocisternostomy, ventriculocystocisternostomy, and cystoventriculostomy and point out specifics deemed to be important to avoid complications and to ensure the best possible outcome for each patient.

Endoscopy-assisted purely total outer wall excision for pediatric Sylvian arachnoid cysts

BACKGROUND

To present a novel endoscopy-assisted surgical strategy of Sylvian arachnoid cysts (ACs).

CASE PRESENTATION

Endoscopy-assisted surgery was performed on 9 children (May 2019-December 2021). All patients were evaluated with CT and/or MRI and had regular follow-up examinations. The procedure consisted of performing a small temporal craniotomy (2 cm) behind the hairline. After dural opening, the surgery was performed with the assistance of a rigid 30-degree transcranial endoscope, self-irrigating bipolar forceps, and other standard endoscopic instruments. Steps included total excision of the AC outer wall and dissection of arachnoid adhesion around the cystic edge to communicate the residual cyst cavity with subdural space. Compared with the microscopical procedure, a 30-degree transcranial endoscope provides a wider view, especially for the lateral part exposure of the outer wall. The average age of the patients was 27.7 months (range 13-44 months). The Sylvian AC was in the right hemisphere in three patients and six in the left, respectively. 1 patient suffered transient postoperative epilepsy. There was no mortality or additional postoperative neurological deficit in this series. All of the patients achieved significant clinical improvement after surgery. Radiological examination after the operation showed a significant reduction in all cases (100%, 9/9) and disappearance in one case (11.1%, 1/9). Postoperative subdural fluid collection occurred in six cases and completely resolved spontaneously in 9 months.

CONCLUSION

The study demonstrated the minimally invasive, safety, and effectivity of the endoscopy-assisted purely total outer wall excision.

Effectiveness of multiple endoscopic fenestrations for the treatment of Sylvian fissure arachnoid cysts: a multicenter study

PURPOSE

Arachnoid cysts are usually asymptomatic lesions. However, they can sometimes cause intracranial hypertension, headache, seizures, focal neurological deficits, and bleeding. The most commonly used surgical techniques are microsurgical cyst fenestration/excision/drainage, cyst shunting, and endoscopic procedures. We aimed to investigate the success of different surgical techniques.

METHODS

Between 2000 and 2021, patients with Sylvan fissure arachnoid cysts who received treatment via an endoscopic approach chosen as the first-line treatment in three centers were enrolled. All case notes and radiological studies were evaluated retrospectively.

RESULTS

The study included 131 (female, n = 28; male, n = 103) patients with a mean age of 87.04 ± 66.76 (range, 0-216) months. Of the patients, 25 had Galassi type II left-sided arachnoid cysts, 33 had Galassi type II right-sided arachnoid cysts, 40 had Galassi type III left-sided arachnoid cysts, and 32 had Galassi type III right-sided arachnoid cysts. No difference was found between patients who underwent single and multiple fenestrations in terms of Galassi type, side, clinical outcome, and cyst size (p > 0.05). On the contrary, the rate of additional surgical intervention was lower in patients with multiple fenestrations than in those with single fenestration (36.10% vs. 5.30%; p < 0.001).

CONCLUSION

Endoscopic fenestration of Sylvian fissure arachnoid cysts is a good alternative to open surgery or cystoperitoneal shunting, and the number of fenestrations made during this surgery decreases the need for a second surgical procedure.

Controversies in the Treatment of Arachnoid Cysts with Special Emphasis on Temporal Arachnoid Cysts

Intracranial arachnoid cysts (ACs) are benign lesions. The incidence in children is 2.6%. ACs are often diagnosed incidentally. Because of the broad use of CT and MR imaging, the frequency of AC diagnosis has increased. In addition, prenatal diagnosis of ACs is becoming more common. This places clinicians in a difficult situation with regard to the optimal treatment, since the presenting symptoms are often vague and operative management includes not negligible risks. It is generally accepted that conservative management is indicated in cases with small and asymptomatic cysts. In contrast, patients with definite signs of raised intracranial pressure should be treated. There are however clinical situations in whom the decision about the preferred treatment is difficult to make. Unspecific symptoms such as headaches and neurocognitive or attention deficits can be challenging to evaluate, whether they are related to the presence of the AC or not. The treatment techniques intent to establish a communication between the cyst and the normal cerebrospinal spaces or consist of a diversion of the cyst fluid by a shunt system. Which surgical method (open craniotomy for cyst fenestration, endoscopic fenestration, or shunting) is preferred differs between neurosurgical centers or the pediatric neurosurgeon in charge. Each treatment option has a unique profile of advantages and disadvantages which should be considered when discussing treatment with the patients or their caregivers.

Clinical variety and prognosis of intracranial arachnoid cysts in children

Arachnoid cysts (AC) occur in different intracranial locations. Management and prognosis depend on the clinical presentation and treatment guidelines do not exist. With this study, we want to demonstrate the clinical variety of arachnoid cysts in children and place a focus on outcome factors in operated cases. This retrospective study of a consecutive single unit series of children, who underwent AC surgery between January 2010 and September 2019, provides demographic, clinical, imaging data, and information about surgical treatment and outcome. Overall, 63 patients (71.4 male) underwent surgery. Mean age was 50 months (0-191). Mean follow-up was 40 months (0-121). Eighty-one percent of patients presented with symptoms/signs of raised ICP. Focal neurological deficits were present in 15.9%, headache in 11.1% of children. Galassi cysts represented the predominant type (30.2%), followed by suprasellar (14.3%), quadrigeminal (12.7%), retrocerebellar, CPA and midline (each 11.1%), and hemispheric cysts (7.9%). Endoscopic and microsurgical fenestrations were performed in 27% and 58.7%, stent or shunt insertion in 6.3%/57.9% of the cases. In 33.3% of the cases one and in 12.7%, a second reintervention became necessary. Reoperation rate was significantly higher in children < 1 year (p = 0.003). Cyst volume decreased in 85.7%. Seventy percent of the patients were symptom free, 5% suffered from headache, and 22% from developmental disorders. All focal neurological symptoms resolved. Complication rate and outcome are depending on age and cyst location. Recurrence and revision rates are significantly higher in young infants (p = 0.003). Midline cysts with CCA are associated with developmental disorders.

Acetazolamide to treat symptomatic ruptured arachnoid cysts: illustrative cases

BACKGROUND

Arachnoid cysts are benign, often asymptomatic intracranial mass lesions that, when ruptured, may cause seizures, raised intracranial pressure, hemorrhage, and/or loss of consciousness. There is no widely agreed upon treatment, and there is debate as to whether a nonoperative or surgical approach is the best course of action. The carbonic anhydrase inhibitor acetazolamide may be an effective nonoperative approach in treating ruptured arachnoid cysts.

OBSERVATIONS

The Pediatric Neurosurgery Clinical Database at BC Children’s Hospital from 2000 to 2020 was queried, and four pediatric patients who were treated with acetazolamide after presentation with a ruptured middle cranial fossa arachnoid cyst were identified. All patients showed some degree of symptom improvement. Three of the patients showed complete reabsorption of their subdural collections in the ensuing 6 months. One patient had an inadequate response to acetazolamide and required surgical management.

LESSONS

Acetazolamide is a safe and reasonable primary treatment option in pediatric patients with ruptured middle cranial fossa arachnoid cysts, and it may help avoid the need for surgery.

Endoscopic fenestration for treating Galassi type III middle cranial fossa arachnoid cysts: single- and multiple-stoma have the same curative effect

Background and Study Aims For endoscopic fenestration of middle cranial fossa arachnoid cysts (MCFACs), the decisions on the location and number of stomas are key issues in the operation. However, research on this particular topic has been limited. Thus, this study aimed to compare single-stoma versus multiple-stoma endoscopic fenestration for treating Galassi type III MCFACs. Patients and Methods This retrospective study included 86 patients with Galassi type III MCFACs treated with endoscopic fenestration. Single-stoma fenestration to the basal cistern was performed in 37 cases, while multiple-stoma fenestration to the basal cistern and the carotid cistern was performed in 49 cases. Clinico-radiological profiles and follow-up data were analyzed. Results The rate of symptom relief was 83.7%(72/86), and the rate of cyst shrinkage was 96.5%(83/86). Postoperative ipsilateral subdural effusion, which was significant(P=0.042), and non-infectious fever were the two most common complications in the single-stoma and multiple-stoma groups. No significant differences in intraoperative nerve injury, vascular injury, proportion of cases with cyst reduction, and symptom remission rate were observed between both groups. The rates of cyst recurrence and secondary surgery in the single-stoma group were higher than those in the multiple-stoma group, although the difference was not significant. Conclusion Endoscopic fenestration is an effective and minimally invasive approach for treating Galassi type III MCFACs. Single-stoma and multiple-stoma have the same curative effect.

Endoscopic Treatment of Middle Cranial Fossa Arachnoid Cysts in Children: Surgical Results of 65 Cases

OBJECTIVE

Congenital arachnoid cysts in the middle fossa accounts for 50% of all intracranial arachnoid cysts. Several management options have been described; however, no single technique has been universally adopted. We describe a series of pediatric patients with middle cranial fossa arachnoid cyst that were treated through an innovative minimally invasive endoscopic technique, along with their clinical aspects and surgical outcomes.

METHODS

Data from 65 patients operated between 2012 and 2018 were retrospectively analyzed. Follow-up ranged from 12 to 96 months. Clinical presentation and surgical outcomes were collected. Endoscopic cystocisternostomy was performed in all patients using a mini endoscope.

RESULTS

There were 41 male and 24 female patients, with a mean age of 5.3 years at the time of treatment. Except for 4 patients, all presented with 1 or more symptoms, and the most frequent were intracranial hypertension signs. All patients were treated with the same surgical technique, with an efficacy of 81.5%.

CONCLUSIONS

Using a mini endoscope allow us to perform multiple fenestrations along the arachnoid and deeply inspect the basal cisterns, achieving a much wider communication between the cyst and subarachnoid space with a high success rate and minimal invasiveness.

Endoscopic treatment of intracranial cysts in infants: personal experience and review of literature

BACKGROUND

A wide variety of intracranial cysts is known to occur in infants. If symptomatic, they require treatment; the ideal surgical treatment and indications of surgery are yet a matter of discussion. Traditional treatment is either by cystoperitoneal shunting, or microsurgical fenestration. Endoscopic treatment is an alternative procedure that avoids the invasiveness of open craniotomy and the complications caused by shunting.

METHODS

This article reviews the endoscopic treatment of intracranial cysts in infants. The author presents personal experience by reviewing the results of endoscopic treatment in different subgroups among his series of pediatric patients extending over 20 years.

RESULTS

Different types of intracranial cysts in infants were discussed and the role of endoscopy in the management of these patients was reviewed. The author also presented the results of endoscopic treatment of a personal series including 87 infants with intracranial cysts operated by the endoscopic procedure.

CONCLUSIONS

It has been recommended to use the endoscopic procedure in the treatment of intracranial cysts in infants, because it is effective, simple, minimally invasive, and associated with low morbidity and mortality rates. However, an important prerequisite is the presence of an area of contiguity with the subarachnoid cisterns and/or the ventricular system.

Surgical management of intracranial arachnoid cysts in pediatric patients: radiological and clinical outcome

OBJECTIVE

Congenital intracranial cysts account for a significant portion of intracranial lesions in the pediatric population. The efficiency of surgical treatment in a pediatric cohort with intracranial arachnoid cysts (ACs) at different locations regarding clinical symptoms and mass effect was evaluated.

METHODS

A retrospective study of all children who underwent surgical treatment of an intracranial AC during an 11-year period (2007-2018) was performed. Demographics, clinical symptoms, and radiological cyst size pre- and postoperatively, as well as the reoperation rate and possible treatment complications, were analyzed.

RESULTS

A total of 116 intracranial cysts at 8 different anatomical locations were surgically treated in 113 children (median age 5 years and 10 months) predominantly by endoscopic technique (84%). The complication rate was 3%, and the reoperation rate was 16%. Preoperative cyst enlargement was significantly more common in infants (p < 0.0001), as was the need for reoperation (p = 0.023). After a median radiological follow-up of 26 months, > 50% reduction of cyst volume was seen in 53 cysts (46%), and 47 cysts (40%) showed a 10%-50% reduction. Acute clinical symptoms improved: nausea and vomiting, accelerated head growth, and headaches improved at 100%, 92% and 89%, respectively. However, chronic symptoms responded less favorably after a median clinical follow-up of 26 months.

CONCLUSIONS

The strategy of predominantly endoscopic treatment with navigation planning is efficient to alleviate clinical symptoms and to significantly reduce the mass effect of pediatric intracranial cysts at different anatomical locations. The subgroup of infants requires close pre- and postoperative monitoring.

Intracranial Venous Sinus Stenting in Idiopathic Intracranial Hypertension: A Case Report and Review of the Literature

We describe a case of severe headaches, double vision, and progressive vision loss secondary to a ruptured intracranial cyst (IAC) in a 31-year-old woman with no relevant past medical history. The case is peculiar because drainage of the subdural hygroma led to a minimal improvement in vision with persistent elevated intracranial pressure (ICP). Further exploration revealed transverse sinus stenosis necessitating stenting. Evaluation post-stenting showed marked reduction of ICP and improvement in symptoms. This report underscores the importance of comprehensive work-up and suspicion of multiple underlying etiologies that may be crucial to complete resolution of presenting symptoms in some cases. We provide an overview of the clinical indications and evidence for venous sinus stenting in treating idiopathic intracranial hypertension (IIH).

Endoscopic Fenestration of Arachnoid Cysts Through Lateral Pontomesencephalic Membranotomy: Technical Note and Case Series

BACKGROUND

The ideal treatment method for cranial arachnoid cysts stills controversial, each of endoscopic and microscopic techniques has its pros and cons.

METHODS

We described cystocisternostomy technique for arachnoid cysts through fenestration medial to the edge of tentorium through lateral pontomesencephalic membrane and illustrated it's outcomes. We performed endoscopic lateral pontomesencephalic membranotomy in nine children with zero angled rigid endoscope (STORZ).The age ranged from eight months up to nine years. The cysts were Galassi type III in eight cases (five of them giant hemispheric) and Galassi type II in one case. Clinical presentations were delay in milestones, seizures, loss of consciousness, unsteady gait, and persistent headache.

RESULTS

The cysts decreased in size in five cases after three months and nearly disappeared after three and 15 months in two cases, and in 18 months in the other two. Preoperative symptoms improved in all cases. Insignificant subdural hygroma was found in five cases, one case developed hydrocephalus four months later treated with a ventriculoperitoneal shunt; contralateral massive subdural hematoma occurred in one case four months after surgery evacuated with two burr holes with good clinical outcome. There was neither cerebrospinal fluid leakage, cranial nerve palsy nor mortality.

CONCLUSIONS

The fenestration through the lateral pontomesencephalic membrane created a shortcut of cerebrospinal fluid flow to the basal cisterns especially cerebellopontine cistern and represents a reliable option with an acceptable success rate. It creates a good drainage to the large cysts.

Stereotactic Internal Shunt Placement in Congenital Intracranial Cysts

INTRODUCTION

Treatment of symptomatic intracranial cysts remains a controversial issue. We present a risk/benefit profile of a minimally invasive, not yet described, stereotactic internal shunt implantation technique. The provided data might serve as a reference against which other treatment modalities could be compared.

METHODS

From our prospective database, we identified a consecutive series of patients with symptomatic, untreated cysts who had undergone internal shunting from 2009 to 2017. We estimated the rates of clinical symptom improvement (RCSI), cyst reduction, total complications, and long-term complications. A minimal follow-up of 6 months was required. The prognostic factors were obtained from logistic regression models. Cyst recurrence-free survival was calculated using the Kaplan-Meier method. The outcomes data were compared with those from reported alternative treatment strategies using χ² statistics.

RESULTS

We included 38 patients. The cyst locations differed greatly and included the cerebellum (n = 2), brainstem (n = 5), and pineal area (n = 4). Cyst-associated hydrocephalus (n = 6) resolved after treatment. The 2-year cyst recurrence-free survival rate was 97%. The RCSI and rate of cyst reduction, total complications, and long-term complications was 91%, 97%, 11%, and 2.6%, respectively. We did not find any risk factors associated with the rate of total complications. The RCSI and rate of total and long-term complications compared favorably (P < 0.01) with the corresponding estimates of alternative treatments (P < 0.01).

CONCLUSIONS

The described stereotactic internal shunt implantation technique is safe and can be successfully applied for treatment of cystic formations in any location in the brain.

Neuroendoscopic treatment of multiple intracranial arachnoid cysts: a case report

Background

Multiple arachnoid cysts are very rare within the central nervous system. The cysts will sometimes increase in size with age, lead to the mass effect or cerebrospinal fluid (CSF) flow obstruction, and cause some symptoms, which requires the surgery intervention.

Case presentation

A 35-year-old female was admitted to our hospital with some symptoms related to hydrocephalus for 1 month. Brain magnetic resonance imaging (MRI) revealed well-marginated cystic lesions with CSF signal intensity in the ventricular and cisternal systems, bilateral temporal lobes, and left occipital lobe. Cine phase-contrast MRI showed the aqueduct of sylvius was blocked by the cyst in the quadrigeminal cistern. We employed endoscopic ventriculocystostomy and septostomy to create the communication of the cyst with ventricular and cistern system. As a result, the patient's symptoms were relieved.

Conclusions

Endoscopic management can be an effective way for treating intracranial multiple arachnoid cysts, which is the first report of this kind. We hope that this report could help improve the management of intracranial arachnoid cysts with the neuroendoscopic technology.

Endoscopic treatment of middle fossa arachnoid cysts

BACKGROUND

Endoscopic treatment of middle fossa arachnoid cysts is an alternative option to microsurgical fenestration and shunting procedures. The procedure is minimally invasive and obviates the morbidity of craniotomy and shunting.

METHODS

Operative charts and videos of patients undergoing endoscopic fenestration of middle fossa arachnoid cysts were retrieved from the senior author's database of endoscopic procedures and reviewed. Description of the surgical techniques was then formulated.

CONCLUSIONS

Endoscopic fenestration of middle fossa arachnoid cysts entails communicating the cyst cavity to the basal cisterns via multiple fenestrations that should be made as large as possible with care to avoid injury of the juxtaposed neurovascular structures.

Augmented reality in intraventricular neuroendoscopy

BACKGROUND

Individual planning of the entry point and the use of navigation has become more relevant in intraventricular neuroendoscopy. Navigated neuroendoscopic solutions are continuously improving.

OBJECTIVE

We describe experimentally measured accuracy and our first experience with augmented reality-enhanced navigated neuroendoscopy for intraventricular pathologies.

PATIENTS AND METHODS

Augmented reality-enhanced navigated endoscopy was tested for accuracy in an experimental setting. Therefore, a 3D-printed head model with a right parietal lesion was scanned with a thin-sliced computer tomography. Segmentation of the tumor lesion was performed using Scopis NovaPlan navigation software. An optical reference matrix is used to register the neuroendoscope's geometry and its field of view. The pre-planned ROI and trajectory are superimposed in the endoscopic image. The accuracy of the superimposed contour fitting on endoscopically visualized lesion was acquired by measuring the deviation of both midpoints to one another. The technique was subsequently used in 29 cases with CSF circulation pathologies. Navigation planning included defining the entry points, regions of interests and trajectories, superimposed as augmented reality on the endoscopic video screen during intervention. Patients were evaluated for postoperative imaging, reoperations, and possible complications.

RESULTS

The experimental setup revealed a deviation of the ROI's midpoint from the real target by 1.2 ± 0.4 mm. The clinical study included 18 cyst fenestrations, ten biopsies, seven endoscopic third ventriculostomies, six stent placements, and two shunt implantations, being eventually combined in some patients. In cases of cyst fenestrations postoperatively, the cyst volume was significantly reduced in all patients by mean of 47%. In biopsies, the diagnostic yield was 100%. Reoperations during a follow-up period of 11.4 ± 10.2 months were necessary in two cases. Complications included one postoperative hygroma and one insufficient fenestration.

CONCLUSIONS

Augmented reality-navigated neuroendoscopy is accurate and feasible to use in clinical application. By integrating relevant planning information directly into the endoscope's field of view, safety and efficacy for intraventricular neuroendoscopic surgery may be improved.

Arachnoid cyst: a further anomaly associated with Kallmann syndrome?

BACKGROUND

Kallmann syndrome (KS) is defined by the association of hypogonadotropic hypogonadism and anosmia. It is characterized by a significant clinical and genetic heterogeneity; actually, it may present several non-reproductive non-olfactory anomalies, and all the ways of genetic transmission can be involved in the inheritance of the disease. Although six pathogenesis-related genes have been identified so far, KS remains sporadic in 70 % of the cases, and the genetic diagnosis is not available for all of them. The purpose of this paper is to present a further disease that can enrich the wide spectrum of KS variability, that is cerebral arachnoid cyst.

CASE DESCRIPTION

This 11-year-old boy presented with the typical characteristics of KS together with those related to a sylvian arachnoid cyst. He was admitted because of worsening headache. At the admission, the physical examination revealed eunuchoid aspect, micropenis, previous cryptorchidism, and anosmia. MRI pointed out a large, left sylvian arachnoid cyst, agenesia of the olfactory bulbs/tracts complex, and hypoplasia of the left olfactory sulcus. The child was operated on by endoscopic fenestration of the cyst, followed by transient external drainage for subdural hygroma and microscopic fenestration for recurrence of the cyst. His statural growth is normal but the sexual development still delayed in spite of hormone replacement therapy.

CONCLUSION

According to the present and the other four cases in the literature, arachnoid cyst should be included among the anomalies possibly accompanying KS date although this association seems to be occasional as far as embryogenesis and physiopathology are concerned.