Symptomatic supratentorial arachnoid cysts in children

Ruptured Sylvian arachnoid cysts: an update on a real problem

PURPOSE

Sylvian arachnoid cysts (SACs) are the most common type of arachnoid cysts and the most prone to undergo a rupture. This event is considered rare but potentially severe. No definite information is available on its occurrence or management. The goal of the present article is to provide an update on the epidemiological, etiological, and clinical aspects and the management of this peculiar clinical condition.

METHODS

A comprehensive review of the English literature of the last 40 years on this topic has been realized. Moreover, a personal series of children investigated and treated in the last 20 years is presented. These patients were managed as follows: (1) treatment of the subdural collection; (2) identification of candidates for surgical treatment of the residual cyst (brain MRI, perfusion brain MRI, prolonged invasive ICP monitoring (selected cases), EEG, neuropsychological tests); (3) surgical treatment of the cyst in the patients with pathological perfusion MRI and/or ICP measurement and/or clear neurophysiological and neuropsychological correlations.

RESULTS

A total of 446 patients (430 from the literature and 16 from the personal series), mainly children, adolescents, and young adults, have been analyzed leading to the following results: (1) SAC rupture is rare but not negligible (yearly risk of rupture: 0.04%; overall risk up to 10% in children affected by SCAs). Prophylactic surgery in asymptomatic cases is not advisable. (2) The mechanism of rupture is not known but an impact of SAC against the sphenoid wing and/or a direct injury on SAC through a thinned temporal bone, with possible laceration of the cyst wall vessels and/or tear of the bridging veins, can be hypothesized. A head injury is often not reported (may be misdiagnosed). (3) Subdural collection (hygroma > chronic hematoma) is the most common finding followed by intracystic bleeding, extradural hematoma, and other types of bleeding. Signs or symptoms of raised intracranial pressure are the most frequent ones. (4) The complication of the rupture is usually treated in emergency or in the acute period by burr hole or craniotomic evacuation of the subdural collection, although a conservative management is possible in some cases. Following the rupture, the majority of SACs are treated (70%), often at the same time of the complication, but no specific investigations are routinely performed to select candidates. According to our protocol, only 43.7% of SACs needed to be treated.

CONCLUSIONS

The "spontaneous" or posttraumatic rupture of SACs is a rare but potentially significant complication followed by a generally good outcome. The course of the cyst is independent from the outcome of the complication, consequently requiring specific investigations for individuating those lesions interfering with CSF dynamics and/or cerebral blood flow.

Impaired visual acuity as an only symptom of shunt malfunction, long time after initial cyst-peritoneal shunting for arachnoid cyst: A case report

Background:

Long-term outcomes after surgical treatment of arachnoid cysts (ACs) have not been reported adequately. Impaired visual acuity is not a common symptom of shunt dependency syndrome due to cyst-peritoneal (CP) shunt malfunction for ACs. We report a case of CP shunt malfunction, who presented only impaired visual acuity as a symptom, long after the initial surgical treatment.

Case Description:

A 16-year-old boy was surgically treated for the left frontal AC with CP shunting at 2 years of age. Extension of the peritoneal shunt catheter was performed at 15 years of age. A year later, he started experiencing impairment of visual acuity without headaches, which worsened to bilateral light perception. The presence of bilateral optic atrophy was confirmed. The AC in the left frontal lobe had enlarged very slightly, with shortening of the intracystic catheter, and the cerebrospinal fluid pressure was elevated to 30 cmH2O. He was treated with lumboperitoneal shunting. The visual acuity showed limited improvement.

Conclusion:

The possibility of CP shunt malfunction and shunt dependency syndrome should be considered, even if the patient presented only impaired visual acuity and no significant changes in the size of the ACs are observed.

Microsurgical Fenestration of Intracranial Arachnoid Cysts: Volumetric Analysis and Clinical Outcome

INTRODUCTION

There is paucity of data regarding change in arachnoid cyst (AC) volume following surgery. This study aimed at investigating the clinical outcome of ACs and applying 2 volumetric methods for determination of their volume change post microsurgical fenestration.

METHODS

Twenty-one ACs in 20 patients that underwent microsurgical fenestration were analyzed using 2 volumetric methods; the modified McDonald equation and the picture archiving and communication (PAC) system-based method. Patients were followed up for 23 ± 40.3 months.

RESULTS

The majority of the patients (13 or 65%) were children. Preoperative symptoms in children were mainly seizures and less commonly headache. Of the 20 patients, 12 (60%) had complete resolution of their preoperative symptoms with 8 (40.0%) showing partial improvement. Volumetric studies showed a mean reduction in AC size of 73.7% in children and 64.4% in adults using the PAC system versus 67.9% in children and 70.5% in adults using the modified McDonald equation method. There was no correlation between the percentage decrease in AC volume post surgery and degree of symptom improvement (49.2 ± 34.3% in patients with complete vs. 60.9 ± 40.3% in patients with only partial resolution of symptoms, p = 0.57).

DISCUSSION/CONCLUSION

Microsurgical fenestration is an effective approach for ACs with an excellent clinical outcome apparent in the complete or partial improvement of symptoms in all patients. Volumetric estimates of ACs and their change following surgery are feasible using the modified McDonald or PAC system methods. However, there is no correlation between the percentage decrease in AC volume after surgery and degree of clinical improvement.

Spontaneous rupture of middle fossa arachnoid cysts: surgical series from a single center pediatric hospital and literature review

PURPOSE

Arachnoid cysts may present with symptoms deriving from cyst rupture, usually causing intracystic hemorrhage and subdural hematoma or hygroma. Rupture is usually caused by minor trauma, spontaneous rupture is an exceptional event, and 57 cases have been described in literature. We here present and discuss the largest series of spontaneously ruptured middle fossa arachnoid cysts in order to investigate clinical presentation and best treatment available.

METHODS

We report a retrospective series of 17 pediatric patients surgically treated for middle fossa arachnoid cyst with signs of cyst rupture without a history of trauma in the previous 90 days. We describe clinical presentation, treatment, and outcome at follow-up discussing our results with a literature review including all reported cases of spontaneous rupture of middle fossa arachnoid cysts.

RESULTS

In our experience patients most frequently presented with subdural hygroma, in literature, a chronic hematoma was most frequently reported. Headache is the most reported symptom at presentation. Neurological deficits and consciousness alterations are rare. Surgical treatment may resolve brain compression only or reduce rupture recurrence risk. Conservative treatment has also been proposed. Different treatments are reported and discussed focusing on indications, contraindications, risks, and expected benefits.

CONCLUSION

We propose, when safely possible, microsurgical cyst fenestration in skull base cisterns as the treatment of choice for these patients as long as it addresses both immediate decompression and risk of rupture recurrence. We report good outcomes and low incidence of complications from our series with a mean postoperative follow-up of 30 months.

Volume change of cranial arachnoid cysts after successful endoscopic fenestration in symptomatic children

INTRODUCTION

Endoscopic fenestration remains a first-line treatment option for symptomatic arachnoid cysts. After fenestration, the cyst does not collapse but reaches an equilibrium state. The aim of this study was to evaluate the change in cyst volume following successful fenestration and symptomatic improvement.

METHODS

Cyst volume was measured on serial MR scans of 4 children (1 female, 3 males) with symptomatic arachnoid cysts (middle fossa n = 2, choroidal fissure n = 1 and posterior fossa n = 1), who experienced symptom resolution after endoscopic fenestration. Average follow-up was 20.5 months (range 3-48).

RESULTS

Significant cyst volume reduction was seen in all four patients. In patient 1, preoperative cyst volume was 336 cm³ and decreased to 194 cm³ at 7 months (42% reduction). In patient 2, preoperative volume was 12.64 cm³ and reduced to 1.51 cm³ at 3 months (88% reduction). In patient 3, preoperative volume was 105 cm³ and reduced to 72 cm³ in 2 months (30% reduction). In patient 4, preoperative volume was 125 cm³ and reduced to 54 cm³ at 7 months (56% reduction). All remained stable after 7 months and there has been no late increase in volume.

CONCLUSIONS

Significant reduction in arachnoid cyst volume at the order of 30-40% is seen after successful endoscopic fenestration. The cyst volume appears to decrease gradually in the first 3-7 months and reaches a plateau after that. Complete resolution of symptoms in the presence of residual volume may indicate that cyst volume below a threshold may not correlate directly with clinical status.

Pediatric intracranial arachnoid cysts: comparative effectiveness of surgical treatment options

PURPOSE

A variety of surgical approaches for the treatment of pediatric intracranial arachnoid cysts exist. In an effort to identify the optimal surgical treatment for this disorder, we developed a decision analytic model to evaluate outcomes of four surgical approaches in children. These included open craniotomy for cyst excision, open craniotomy for cyst fenestration, endoscopic cyst fenestration, and cystoperitoneal shunting.

METHODS

Pooled data were used to create evidence tables, from which we calculated incidence, relative risks, and summary outcomes in quality-adjusted life years (QALYs) for the four surgical treatments. Our study incorporated data up to 5 years postsurgery.

RESULTS

We analyzed 1,324 cases from 36 case series. There were no significant differences in outcome among the four surgical strategies. The QALYs (maximum of 5) for surgical approaches resulted in a range from 4.79 (for open craniotomy and excision) to 4.92 (for endoscopic fenestration).

CONCLUSIONS

Overall quality of life is comparable between patients undergoing open craniotomy for cyst excision or fenestration, endoscopic fenestration, and cystoperitoneal shunting up to 5 years after surgery. While each approach offers unique advantages and disadvantages, an individualized treatment strategy should be employed in the setting of surgical outcome equipoise.

Institutional experience of endoscopic suprasellar arachnoid cyst fenestration

INTRODUCTION

Suprasellar arachnoid cysts can differ from other arachnoid cysts in several ways, making a separate analysis of these cysts worthwhile. Herein, we present the outcome and perform volumetric analysis of six children with suprasellar arachnoid cysts treated with endoscopic ventriculocystocisternostomy in order to evaluate the long-term outcomes.

PATIENTS AND METHODS

Operative and postoperative data were retrospectively reviewed for six patients harboring suprasellar arachnoid cysts. Imaging was then used to follow success of surgical intervention.

RESULTS

Six patients with suprasellar arachnoid cysts underwent ventriculocystocisternostomy. Presenting symptoms were headaches in three patients, developmental delay in another, and an incidental finding in the remaining patients. All patients had enlarged lateral and third ventricles on initial imaging. Average age at presentation was 145.7 months (65.4-250.2). Follow-up was an average of 46.5 months (3-84). The average cyst size was 153.96 cm(3) (42.98-369.20) preoperatively and an average of 39.92 cm(3) (3.20-101.47) at follow-up.

CONCLUSIONS

Based on our experience, suprasellar arachnoid cyst treatment with ventriculocystocisternostomy is an adequate surgical intervention. Suprasellar and third ventricular size does respond to the surgical intervention at long-term follow-up.

Hydrocephalus and arachnoid cysts

AIM

The management of arachnoid cysts (AC) remains controversial. An additional problem derives from the management of hydrocephalus associated with an AC. In this work, we discuss existing procedures proposed in the current literature for their treatment.

METHODS

We reviewed selected reports on intracranial ACs placing special interest in those about the association of hydrocephalus and ACs. We also briefly surveyed data of our patients with this association.

RESULTS AND DISCUSSION

Hydrocephalus is often found in midline and posterior fossa ACs. Interhemispheric lesions may also evolve with ventriculomegaly, while middle fossa lesions rarely produce hydrocephalus. Patients' age, cyst location and size, and macrocephaly have all been related to the development of hydrocephalus. Some authors remark on the role played by hydrocephalus and hypothesize that some ACs would result from disturbed cerebrospinal fluid (CSF) dynamics. They also propose that ACs might represent a localized form of hydrocephalus. We also comment on hydrocephalus in relation to the diverse locations of ACs. Neuroendoscopic techniques have transformed previous ways of management as cystoperitoneal shunting and open fenestration.

CONCLUSIONS

ACs may be pathogenetically related with hydrocephalus, and conversely, ACs may cause hydrocephalus. In some patients, aberrant CSF dynamics seems to play a major role in the development of both cyst and hydrocephalus. Hydrocephalus and ACs may be treated exclusively with neuroendoscopic procedures, although some patients will still require CSF shunting. The ideal option seems to consist of choosing the method that offers the highest success with a single procedure for treating the hydrocephalus and the AC simultaneously.

Apparently novel genetic syndrome of pachygyria, mental retardation, seizure, and arachnoid cysts

We report on an apparently new syndrome in a consanguineous family with seven members, three of whom have cerebral anomalies including pachygyria and arachnoid cysts along with mental retardation and seizures. The two patients with seizure disorders also had multiple enlarged perivascular spaces seen in the white matter of the centrum semiovale. Our data provide a contribution to the accumulating knowledge on familial cerebral anomalies including arachnoid cysts and lissencephaly. Given the lack of mutation in known lissencephaly genes such as LIS1, 14-3-3epsilon, and DCX, this syndrome may constitute a new phenotype with autosomal recessive inheritance.

Quality of life in adult patients with primary intracranial arachnoid cysts

BACKGROUND

Primary arachnoid cysts are benign developmental lesions of arachnoid mater. Arachnoid cysts may be detected due to various neurological symptoms, or they may be encountered as incidental findings of neuroimaging. Consequently, a significant share of the patients seems asymptomatic. There are diverging opinions about the clinical importance of cyst sizes, cyst location and degree of volume reduction after surgery, hence contributing to controversies regarding indications for surgical treatment. We present the first study assessing internationally established parameters of quality of life and mental health in a clinical-outcome analysis of adult patients with arachnoid cysts.

METHOD

Ninety-two adult patients with arachnoid cysts who had been referred to our department over the last 16 years were included. Forty-seven patients had undergone surgery and 45 patients had not been operated on. Data for analysis was based on both medical records and questionnaires sent out by mail. Quality of life was assessed by the Short Form 36 Health Survey (SF-36), and mental health was further evaluated by the Hospital Anxiety and Depression Scale (HADS). Seventy-one percent of patients responded to our questionnaires.

FINDINGS

There was a great variation in the presenting symptoms, seemingly without any relation to cyst localisation. Patients with arachnoid cysts seem to have a reduced quality of life and a very high prevalence of anxiety compared to a healthy normal population. Men presented lower outcome scores than women. Subjects with symptoms, that we retrospectively labeled biologically comprehensible, tended to have higher quality of life, less anxiety and better subjective symptom relief after surgery.

CONCLUSION

Our arachnoid cyst population had a low employment status, decreased quality of life scores and prevalent symptoms of anxiety. We argue that the arachnoid cysts are, in most cases, not directly related to these studied parameters. We speculate that our findings may reflect the demographic characteristics of adults likely of being diagnosed with incidental cysts. A better clinical outcome for patients with biologically plausible symptoms supports a neurobiological approach in the selection of patients suited for surgery.

Helmetlike skull deformity with a large arachnoid cyst

BACKGROUND

It is not difficult to find localized skull ballooning or macrocrania in patients with intracranial arachnoid cysts. However, there have been no previous reports regarding large localized skull protuberant deformities resembling a war helmet. The authors report with a review of literature a case of an adult with helmetlike skull deformity resulting from a large supratentorial arachnoid cyst.

CASE DESCRIPTION

A 35-year-old man presented with a large head deformity since his early childhood that had been the result of gradual progression from infantile macrocrania. He also had mental retardation, sixth cranial nerve palsy with recent aggravation of headache, reduced activity, poor voiding control, and walking disturbance. Magnetic resonance imaging of the head showed hydrocephalus with a large supratentorial arachnoid cyst located in the bilateral parietooccipital area compressing the hemisphere anteriorly, and the tentorium and cerebellum inferiorly. Magnetic resonance venogram demonstrated low-lying short transverse and lateral sinuses, and the superior sagittal sinus and falx were displaced to the right side. Radioisotopic cisternogram showed nonfilling of the isotope in the bilateral parietooccipital area. Cerebrospinal fluid pressure measured by lumbar puncture was 17 cm H(2)O. We tentatively diagnosed the condition as normopressure hydrocephalus with a large supratentorial arachnoid cyst. His headache, reduced activity, poor voiding control, and walking disturbance improved after a cystoperitoneal shunt.

CONCLUSIONS

This might suggest that large arachnoid cysts found in childhood should be treated for prevention of skull deformity and late aggravation of increased intracranial pressure.

Familial arachnoid cysts

Arachnoid cysts are a relatively common incidental finding on neuroimaging studies of the brain. Although most cases are sporadic, there have been some reports of arachnoid cysts in several members of the same family. This report describes two additional families with three members affected in each one. Both families had members with arachnoid cysts in two consecutive generations. In one of the families, arachnoid cysts were associated with a deletion in the long arm of chromosome 16, an association not described previously. These descriptions suggest that in some cases arachnoid cysts may have a genetic basis.