Nontraumatic symptomatic de novo arachnoid cyst in an adolescent patient treated with cystoperitoneal shunting: illustrative case.

BACKGROUND: Arachnoid cysts are often congenital, asymptomatic lesions detected in the pediatric population. When seen in adults, they usually occur following trauma. De novo formation of arachnoid cysts is uncommon, with only a few instances cited in the literature and most of which occurred in the pediatric population. Treatment options for these lesions include observation, craniotomy for cyst resection, microsurgical/endoscopic fenestration, or shunting. OBSERVATIONS: In this report, the authors describe a female patient with a de novo, symptomatic, enlarging middle cranial fossa arachnoid cyst detected at age 16 years. She was treated with the placement of a cystoperitoneal shunt. After surgery, she experienced clinical and radiological improvement. LESSONS: We illustrate successful shunting of a de novo arachnoid cyst in a symptomatic teen patient. Although arachnoid cysts in certain intracranial locations are more likely to produce symptoms, those in the middle cranial fossa tend to be asymptomatic. To our knowledge, this is the first reported case of a symptomatic de novo arachnoid cyst located in the middle cranial fossa in a postpubertal patient. Although the current presentation is rare, the authors demonstrate an effective surgical treatment of a symptomatic, large, de novo arachnoid cyst in a postpubertal pediatric patient.

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.

Ventral cervico-thoracic meningeal cyst resulting in myelopathy: Case report and literature review.

BACKGROUND: Spinal meningeal (dural) cysts rarely cause spinal cord compression and/or myelopathy. CASE DESCRIPTION: A 38-year-old male presented with 6 weeks of worsening bilateral lower extremity paresthesias and an unsteady gait. Notably, the patient was involved in a snowmobile accident 7 years ago that resulted in trauma to his thoracic spine for which he had undergone a corpectomy and posterior fusion. A full spine MRI was obtained to evaluate his new paresthesias and myelopathy, which revealed a large extra-axial fluid collection consistent with a meningeal cyst extending from C2 to T4. This caused severe spinal cord compression, maximal at the T1-3 level. The patient underwent a T1-3 laminectomy initially accompanied by partial cyst resection/ drainage, but ultimately he returned and required a subsequent cystoperitoneal shunt. Following the final surgery, the patient's symptoms gradually resolved over 6 months postoperatively. CONCLUSION: Spinal meningeal cysts rarely cause back pain and/or neurological symptoms. MRI is the diagnostic study of choice for defining this entity. Operative intervention must be tailored to the symptoms, location, extent, and type of the cyst. If cysts recur after partial resection and drainage, cystoperitoneal shunt placement is warranted.

Shunt complications and revisions in children: A retrospective single institution study.

INTRODUCTION: Shunt surgery in children is associated with high revision and complication rates. We investigated revision rates and postoperative complications to specify current challenges associated with pediatric shunt surgery. METHODS: All patients aged < 18 years admitted to St. Olavs University Hospital, Norway, from January 2008 through December 2017, who underwent primary shunt insertions, were reviewed. Follow-up ranged from 1 to 10 years. Ventriculoperitoneal, cystoperitoneal, and ventriculoatrial shunts were included. All subsequent shunt revisions and 30-day postoperative complication rates were registered. RESULTS: 81 patients underwent 206 surgeries in the study period. 47 patients (58%) required minimum one revision during follow-up. In 14 (29.8%), the first revision was due to the misplacement of hardware. Proximal occlusion was the most common cause of revision (30.4%), followed by misplacement (18.5%) and infection (9.6%). Young age and MMC were associated with revision surgery in a univariable analysis, but were not significant in multivariable analyses. Congenital hydrocephalus was associated with infection (p = .028). In approximately 30% of procedures, complications occurred within 30 days postoperatively, the most common being revision surgery. In approximately 5% of the procedures, medical complications occurred. CONCLUSION: Children are prone to high revision and complication rates, and in this study, misplacement of hardware and proximal occlusion were the most common. Complication rates should not be limited to revision rates only, as 30-day complication rates indicate a significant rate of other complications as well. Multi-targeted approaches, perhaps focusing on measures to reduce misplacement, may be key to reducing revision rates.

Predicting outcomes in Dandy-Walker malformation: a retrospective cohort study.

OBJECTIVE: Dandy-Walker malformation (DWM) is a disorder that most neurologists and neurosurgeons will manage at some point during their careers. It is characterized by partial or complete dysgenesis of the cerebellar vermis. Outcomes are highly variable and range from functionally normal to severely disabled. Predicting these outcomes has classically been focused on the radiological findings that constitute DWM. Other anomalies that can be commonly found in these patients are potentially more indicative of outcome than the tenet markers of DWM. Furthermore, hydrocephalus is an ever-present danger in these patients, many of whom will be admitted to the hospital due to this condition. This study aims to identify these items as potential predictors of outcome. METHODS: All referrals from antenatal anatomy scans between 1992 and 2013 that were suspicious for DWM were reviewed. Neurosurgery archives were reviewed for outpatient letters and other correspondence. The number of DWM diagnoses was quantified. Outcomes were judged based on patient status, ranging from death to attending normal school. The presence of any other anomalies was quantified and measured against patient outcomes. RESULTS: Cyst size and the presence of another CNS anomaly were shown to portend worse outcomes. Non-CNS anomalies and hydrocephalus were not predictive of worse outcomes. Furthermore, of all the treatments assessed, ventriculoperitoneal shunts were shown to be the most effective in this data set. CONCLUSIONS: Results from this study suggest a pivot in how prognoses in DWM should be established and how parents should be counseled, along with a view of hydrocephalus and its treatment that challenges the current literature.

Results of Surgical Treatment in Patients with Intracranial Arachnoid Cyst During Last 5 Years in a Referral Center in a Developing Country: Shiraz, Iran.

OBJECTIVE: To report the outcome of surgical intervention in patients diagnosed with arachnoid cyst (AC) during the last 5 years in Namazi Hospital, a tertiary center in Southern Iran. METHODS: Hospitalization records of patients who had undergone surgical treatment of symptomatic intracranial AC in our center were surveyed retrospectively. Radiologic imaging was extracted from the picture archiving and communication system and analyzed. Postoperative evaluation of patients was conducted in neurosurgery clinic during their routine follow-up. RESULTS: Twenty-nine patients (11 female, 18 male) with an age range of 13 days to 35 years were enrolled in this study. Most (62%) of all ACs were in the temporal area, 12% in the suprasellar region, 6% in the quadrigeminal region, 6% in the cerebellopontine angle, and 3% in the anterior frontal area. Twenty-six endoscopic intervention, 2 microsurgical resection, and 1 cystoperitoneal shunt were performed. All of the patients showed complete resolution or improvement in symptoms. Eighty-nine percent of patients also showed reduction in the cyst size. Ten patients had transient postoperative complications, which were resolved at the time of follow-up. CONCLUSIONS: Diagnosis and appropriate surgical treatment of AC can alleviate the symptoms in patients who fulfill the criteria for surgery. Neuroendoscopy can provide a satisfactory result in symptomatic patients, whilst having less invasiveness and long-term complications. Reoperation should also be considered in situations where medical therapy fails to manage the complications.

Giant Arachnoid Cyst Associated with an Orbital Meningocele: A Case Report and Cystoperitoneal Shunt Management.

INTRODUCTION: Intracranial arachnoid cysts (ACs) are space-occupying lesions that typically remain stable in size and clinically silent over time. CASE REPORT: We describe an unusual pediatric case of enlarged AC impressive by its compressive phenomena. An 11-month-old girl presented with remarkable macrocephaly associated with a cystic orbital tumor. CT scan and MRI studies revealed a large intracranial ACs extending in the orbit with an orbital meningocele (OM). The intracranial cyst did communicate with the orbital one into a bony defect in the right inner region of the orbital roof and represses the globe outward. A cystoperitoneal shunting procedure was performed to remove the mass effect as soon as possible and facilitate normal development. DISCUSSION/CONCLUSION: Cysts in infants younger than 1 year of age are remarkably different from those in older children and adults in terms of cyst localization and enlargement. Classically described complications result from compression of adjacent structures and include focal neurologic involvement, headaches and seizures and developmental deficits, or macrocephaly in younger children. There are few cases of ACs with ophthalmic manifestations reported in the literature. The paucity of literature prompted us to analyze the case. To the best of our knowledge, an AC accompanying OM has not been reported. The pathogenesis and management of the case will be discussed.

The efficacy of cystoperitoneal shunting for the surgical management of intracranial arachnoid cysts in the elderly: A systematic review of the literature.

BACKGROUND: Intracranial arachnoid cysts (AC) are benign, cerebrospinal fluid filled spaces within the arachnoid layer of the meninges. Neurosurgical intervention in children and young adults has been extensively studied, but the optimal strategy in the elderly remains unclear. Therefore, we performed a single center retrospective study combined with a systematic review of the literature to compare cystoperitoneal (CP) shunting with other surgical approaches in the elderly cohort. METHODS: Retrospective neurosurgical database search between January 2005 and December 2018, and systematic review of the literature using PRISMA guidelines were performed. Inclusion criteria: Age 60 years or older, radiological diagnosis of intracranial AC, neurosurgical intervention, and neuroradiological (NOG score)/clinical outcome (COG score). Data from both sources were pooled and statistically analyzed. RESULTS: Our literature search yielded 12 studies (34 patients), which were pooled with our institutional data (13 patients). CP shunts (7 patients; 15%), cyst fenestration (28 patients; 60%) and cyst marsupialisation/resection (10 patients; 21%) were the commonest approaches. Average duration of follow-up was 23.6, 26.9, and 9.5 months for each approach, respectively. There was no statistically significant association between choice of surgical intervention and NOG score (P = 0.417), COG score (P = 0.601), or complication rate (P = 0.955). However, CP shunting had the lowest complication rate, with only one patient developing chronic subdural haematoma. CONCLUSION: CP shunting is a safe and effective surgical treatment strategy for ACs in the elderly. It has similar clinical and radiological outcomes but superior risk profile when compared with other approaches. We advocate CP shunting as first line neurosurgical intervention for the management of intracranial ACs in the elderly.

A Case of Miyazaki Syndrome Caused by Arachnoid Cyst-Peritoneal Shunt.

BACKGROUND: Miyazaki syndrome is overshunting-associated myelopathy, which is a rare complication of ventriculoperitoneal shunt. We present the first case of Miyazaki syndrome caused by cystoperitoneal (CP) shunt for an arachnoid cyst (AC) in this report. CASE DESCRIPTION: We report a case of a 42-year-old man with 12-year progressive spastic paraplegia, who underwent CP shunt for an AC at the age of 15 years. Although few findings suggested overshunting on symptoms and head computed tomography, contrast-enhanced magnetic resonance imaging revealed the engorgement of the cervical spinal epidural venous plexus compressing the spinal cord. Shunt valve replacement with a pressure-adjustable valve was performed. Postoperatively, the cervical cord compression by the enlarged spinal epidural venous plexus was completely improved, but, possibly due to delayed diagnosis and treatment, the patient's symptoms only partially improved. CONCLUSIONS: When patients with a history of any kind of shunt surgery develop myelopathy, Miyazaki syndrome should be suspected and, for early diagnosis, cervical and/or contrast-enhanced magnetic resonance imaging should be performed.

Symptomatic lateral ventricular cystic lesion in a young cat.

CASE SUMMARY: A 1.5-year-old male neutered Persian cat was referred for acute deterioration of chronic left head tilt and ataxia. A lateral intraventricular cystic lesion, closely associated with the left choroid plexus, was identified on MRI. The intralesional signal intensity and cytological analysis of the fluid revealed a liquid similar to cerebrospinal fluid. After trepanation, an endoscopic-assisted fenestration and aspiration of the cyst were performed to temporally relieve the high intracranial pressure while waiting for surgical cystoperitoneal shunt placement. Three weeks after surgery, clinical relapse and recurrence of the lesion were noted on the pre-cystoperitoneal shunting MRI. During anaesthesia, the cat arrested. Cardiac resuscitation was successfully performed and cystoperitoneal shunting was postponed. Global brain ischaemia was then suspected, based on major forebrain clinical signs and MRI abnormalities. During a 6-month recovery period, a further three fine-needle CT-guided aspirations of the lesion were required, owing to clinical recurrence and increased cyst size. Cystoperitoneal shunting was eventually performed, allowing persistent reduction of the lesion and long-term improvement of the cat's neurological status. RELEVANCE AND NOVEL INFORMATION: This is the first report of a symptomatic lateral intraventricular cystic lesion in a cat. A left lateral intraventricular choroid plexus cyst was suspected based on the MRI features. Our case suggests that endoscopic fenestration and CT-guided aspiration are not adequate treatments for long-term management. Cystoperitoneal shunting may be a safe procedure, allowing significant and stable reduction of the cystic lesion, associated with improvement in the cat's neurological status by preventing high intracranial pressure.

Two different indications of ventriculoperitoneal and cystoperitoneal shunting in six dogs.

In this study we described two different indications of ventriculo- and cystoperitoneal shunting (VPS, CPS) procedures in six dogs, including their clinical data and magnetic resonance imaging (MRI) examinations. One dog had moderate and two dogs had severe congenital hydrocephalus, one was presented with intracranial pressure elevation due to meningoencephalitis of unknown origin (MUO) associated with congenital hydrocephalus, and two with quadrigeminal cysts (QC). VPS procedures were done in four and CPS in two dogs, using low-pressure valve systems. The follow-up period ranged from 1 to 6 months and control MRI scans were also made. Significant improvement was detected in five cases during the short-term follow-up period (1 month) and in four cases in the medium-term follow-up (2-6 months). Major complications were found in two cases: one dog with acute-hypertensive hydrocephalus died one week after surgery, and in another case development of a chronic subdural haematoma and hygroma caused death 3 months after the surgery. Minor complications (e.g. subdural hygroma) were found in two cases. In cases of severe hydrocephalus or intracranial cysts, higher-pressure valve systems are recommended in order to prevent subdural hygroma. Transient postoperative clinical signs usually resolve within one week after the surgery.

Microsurgical, endoscopic, and shunt management of pediatric temporosylvian arachnoid cysts: a comparative study.

OBJECTIVE: Arachnoid cysts (ACs) are most frequently located in the middle cranial fossa. Some patients are asymptomatic whereas others exhibit signs of increased intracranial pressure, seizures, or cognitive and behavioral symptoms. When ACs do require treatment, the optimal surgical technique remains controversial. This study was conducted to assess the most effective surgical treatment for these cysts. METHODS: The authors retrospectively reviewed 240 temporal intracranial ACs managed over a 25-year period in their pediatric neurosurgical unit. Pre- and posttreatment results were clinically and radiologically assessed. RESULTS: A majority of male patients (74.6%) with an overall median age of 6.9 years were included. The mean cyst size was 107 cm3; the Galassi classification showed 99 (41.3%) type I, 77 (32.1%) type II, and 64 (26.7%) type III cysts. Forty-four ACs (18.3%) were diagnosed after rupture. Surgical management was performed by microsurgery (28.3%), endoscopic cyst fenestration (14.6%), cystoperitoneal shunting (CPS; 16.2%), or subdural shunting (10%). Furthermore, 74 children (30.8%) did not undergo operations. After a mean follow-up of 4.1 years, the mean percentage decrease in cyst volume and the overall rate of clinical improvement did not significantly differ. The endoscopy group had earlier complications and a shorter event-free survival (EFS) time (EFS at 3 years = 67.7%, vs 71.5% and 90.5% for CPS and microsurgery, respectively; p < 0.007) and presented with more subdural hematomas compared to the microsurgery group (p < 0.005). The microsurgery group also showed a tendency for longer cystocisternostomy permeability than the endoscopy group. CONCLUSIONS: Concerning the management of unruptured symptomatic temporal ACs, microsurgery appears to be the most effective treatment, with longer EFS and fewer complications compared to shunting or endoscopy.

Rare Case of Tricompartmental Arachnoid Cyst Spanning Infratentorial, Supratentorial, and Extracranial Compartment and Presenting as Posterior Parietal Meningocele.

BACKGROUND: Arachnoid cysts constitute a mere 1% of all nontraumatic intracranialspace-occupying lesions, and only 10% of these are present in theinfratentorial compartment. We hereby report a case of a 10-month-old femalechild with a tricompartmental arachnoid cyst. CASE DESCRIPTION: The arachnoid cyst spanned both the infratentorial and supratentorialcompartment of the intracranial space. In addition, the cyst was alsoherniating into the extracranial compartment through a congenital defect in theparietal bone. The child was brought to us with a disfiguring swelling over herscalp, which was progressively increasing in size. We managed the patient byexcision of the extracranial part and placed a cystoperitoneal shunt to take care of the intracranial part. Follow-up magneticresonance imaging after 6 months of intervention showed a significant reductionin the size of the intracranial portion of the cyst with no recurrence of theextracranial part. CONCLUSIONS: This case of arachnoid cyst involves multiplestructures. But interestingly, all these structures (arachnoid, dura, veins,and bone) are of mesodermal origin. So we would like to suggest that thispathology may be a result of developmental deviation during mesodermal differentiationrather than a simple expanding arachnoid cyst.

Tailored Strategies to Manage Cerebrospinal Fluid Leaks or Pseudomeningocele After Surgery for Tethered Cord Syndrome.

BACKGROUND: Cerebrospinal fluid (CSF) leaks are a dreaded complication after surgery for tethered cord and are associated with significant patient morbidity. Although many strategies for managing postoperative CSF leaks exist, this problem is still daunting, especially in very young patients. In this study, we compared different management techniques for CSF leaks or significant pseudomeningocele in patients with tethered cord syndrome (TCS). METHODS: We analyzed a cohort of children who underwent surgery for TCS from January 2011 to March 2016 (n = 260) and postoperatively experienced either a CSF leak or significant pseudomeningocele. A subset of patients presented with CSF leak (n = 25). We analyzed patient age, sex, presentation, leak appearance, management, and outcome. The different techniques of management were compared for efficacy and morbidity. RESULTS: The diseases associated with leak formation included lipomyelomeningocele (n = 16), myelocystocele (n = 4), and myelomeningocele (n = 5). Three children also had hydrocephalus. Management techniques included cystoperitoneal shunt (CPS) (n = 15), primary resuturing with local rotation flap of muscle (n = 3), external ventricular drain placement (n = 1), ventriculoperitoneal shunt (n = 3), external ventricular drainage (n = 1), and a combination of techniques (rotation flap with external drain; n = 1). Five patients who underwent primary wound revision experienced a leak and required a secondary intervention, but none of the patients who underwent CPS had any complications. CONCLUSIONS: In carefully selected cases, CPS performed early after CSF leakage is highly successful with low morbidity. The primary closure can be attempted for low-pressure leaks without an associated pseudomeningocele.

Bobble-head doll syndrome in an 80-year-old man, associated with a giant arachnoid cyst of the lamina quadrigemina, treated with endoscopic ventriculocystocisternotomy and cystoperitoneal shunt.

Bobble-head doll syndrome (BHDS) is a rare entity, characterized by antero-posterior head bobbing, which is of the type "yes-yes." Less frequently, having a head movement of the type "no-no" is described. We report an unusual case of an 80-year-old man with a cystic mass of the lamina quadrigemina, extending to the posterior fossa. We conclude that ventriculocystocisternotomy associated with a cystoperitoneal shunt is an effective treatment for a symptomatic giant arachnoid cyst in the lamina quadrigemina.

Remote Cervical Pseudomeningocele Following Anterior Cervical Corpectomy and Fusion: Report of a Case and Review of the Literature.

Iatrogenic cervical pseudomeningocele is a rare event and majority are located posteriorly as a delayed complication of inadvertent dural tear after decompressive laminectomy. However, iatrogenic anterior cervical pseudomeningocele subsequent to discectomy or corpectomy is a rare pathology. The time necessary for formation of pseudomeningocele varies and depend on the width of the dural tear and the flow of cerebrospinal fluid leakage. Large tears with high CSF flow usually result in early collection of the cerebrospinal fluid in anterior compartment of the neck designated acute pseudomeningoceles. Micro-tears of dura mater, with low flow of cerebrospinal fluid may lead to late formation of a pseudomeningocele known as chronic ones. Herein a 49- year-old woman in whom cervical pseudomeningocele appeared clinically as a mass on the anterior aspect of the neck, six months after anterior cervical corpectomy for cervical spondylotic myelopathy is presented. Otherwise, she was neurologically stable. Cystoperitoneal shunt was proposed which she refused. Surprisingly, at 2-year follow-up, the cyst had remained of the same size. To the best of our knowledge, this is the first example of post-operative chronic cervical pseudomeningocele in the literature, the event that might propose the self-limited natural course of this rare pathology in chronic cases.

A refractory arachnoid cyst presenting with tremor, expressive dysphasia, and cognitive decline.

BACKGROUND: Arachnoid cysts are common incidental findings on intracranial imaging, although they are rarely symptomatic. CASE DESCRIPTION: We present a case of a 49 year-old woman with a recurrent left supraorbital arachnoid cyst who developed staring spells, expressive dysphasia, and tremor after cyst fenestration and cystoperitoneal shunting. Her symptoms resolved after removing the shunt valve and creating a valveless system. The case is discussed and the literature reviewed. CONCLUSION: We present a case of a recurrent arachnoid cyst that developed worsening and new symptoms after cysto-peritoneal shunting with a programmable valve, which reducing the pressure in the cyst resulted in remarkable resolution of her symptoms.

Pediatric interhemispheric arachnoid cyst: An institutional experience.

BACKGROUND: Interhemispheric arachnoid cysts (IHACs) are a rare type of congenital arachnoid cyst accounting for <5% of all cases. The optimum surgical management of symptomatic IHAC is still controversial, and there are no clear guidelines. MATERIALS AND METHODS: Retrospective analysis of six pediatric patients of IHAC operated from 2012 to 2015 at our institute. There was definitive sex predisposition with all patients being males. Endoscopic cystoventriculostomy, cystocisternostomy, and cystoperitoneal shunt surgeries were performed in three patients each. RESULTS: The median age at presentation was 13 months. The most common clinical presentations were macrocrania with rapidly increasing head size, seizures, infantile spasms, and developmental delay. The mean duration of follow-up was 24.16 months (range: 3-36 months). Cyst size decreased in all the patients on follow-up imaging. Head size stabilized in all the patients. None of the patients required a second surgical procedure till the last follow-up. CONCLUSIONS: Both endoscopic cyst fenestration and shunt surgery are safe and effective in management of IHAC.

Exploring predictors of surgery and comparing operative treatment approaches for pediatric intracranial arachnoid cysts: a case series of 83 patients.

OBJECT: Although intracranial arachnoid cysts are a common incidental finding on pediatric brain imaging, only a subset of patients require surgery for them. For the minority who undergo surgery, the comparative effectiveness of various surgical approaches is debated. The authors explored predictors of surgery and compared operative techniques for pediatric patients with an intracranial arachnoid cyst seen at a tertiary care center. METHODS: The authors reviewed records of pediatric patients with an intracranial arachnoid cyst. For each patient, data on baseline characteristics, the method of intervention, and surgical outcomes for the initial surgery were extracted, and cyst size at diagnosis was calculated (anteroposterior × craniocaudal × mediolateral). Baseline variables were analyzed as predictors of surgery by using logistic regression modeling, excluding patients whose surgery was not related to cyst size (i.e., those with obstructive hydrocephalus secondary to the cyst compressing a narrow CSF flow pathway or cyst rupture/hemorrhage). Data collected regarding surgical outcomes were analyzed descriptively. RESULTS: Among 83 pediatric patients with an intracranial arachnoid cyst seen over a 25-year period (1989-2013), 27 (33%) underwent surgery; all had at least 1 cyst-attributed symptom/finding. In the multivariate model, age at presentation and cyst size at diagnosis were independent predictors of surgery. Cyst size had greater predictive value; specifically, the area under the curve for the receiver-operating-characteristic curve was 0.89 (95% CI 0.82-0.97), with an ideal cutoff point of ≥ 68 cm(3). This cutoff point had 100% sensitivity (95% CI 79%-100%), 75% specificity (95% CI 61%-85%), a 53% positive predictive value (95% CI 36%-70%), and a 100% negative predictive value (95% CI 91%-100%); the positive likelihood ratio was 4.0 (95% CI 2.5-6.3), and the negative likelihood ratio was 0 (95% CI 0-0.3). Although the multivariate model excluded 7 patients who underwent surgery (based on prespecified criteria), excluding these 7 cases did not change the overall findings, as shown in a sensitivity analysis that included all the cases. Descriptive results regarding surgical outcomes did not indicate any salient differences among the surgical techniques (endoscopic fenestration, cystoperitoneal shunting, or craniotomy-based procedures) in terms of symptom resolution within 6 months, need for reoperation to date, cyst-size change from before the operation, morbidity, or mortality. CONCLUSIONS: The results of these exploratory analyses suggest that pediatric patients with an intracranial arachnoid cyst are more likely to undergo surgery if the cyst is large, compresses a narrow CSF flow pathway to cause hydrocephalus, or has ruptured/hemorrhaged. There were no salient differences among the 3 surgical techniques for several clinically important outcomes. A prospective multicenter study is required to enable more robust analyses, which could ultimately provide a decision-making framework for surgical indications and clarify any differences in the comparative effectiveness of surgical approaches to treating pediatric intracranial arachnoid cysts.

Fractured inlet connecting tube of the flat bottom flushing device of a posterior fossa cystoperitoneal shunt.

BACKGROUND: There are well-known complications for shunt procedures. Shunt fracture or disconnection is the second most frequent cause of shunt malfunction in children. Shunt disconnection is not a common cause of shunt malfunction in the early period after installation, especially in the adulthood. CASE DESCRIPTION: Fracture of the proximal (inlet) connector of a flat-based shunt installed for decompression of a large posterior fossa arachnoid cyst in a 31-year-old female with signs of increased intracranial pressure led to recurrence of her symptoms 6 months after surgery. CONCLUSION: Awareness of the possibility of fracture site in the junction of the inlet connector of flat bottom shunt systems is warranted and can be diagnosed by three-dimensional computed tomography (3D CT) imaging without performing shunt series study.