Colloid Cyst Research Articles

Isolated entrapment of the lateral ventricle after neuroendoscopic resection of colloid cysts: single – center experience and management

BackgroundA minimally invasive option of colloid cyst surgical treatment is endoscopic resection, well validated in various reports and clinical practice. A rare complication of the surgical treatment, previously reported only once in literature, is the entrapment of the lateral ventricle. In this study we aim to outline our experience in the management of this occurrence, hypothesizing possible etiopathogenetic causes. MethodsAmong patients who underwent neuroendoscopic resection for a colloid cysts at our Institution between 2013 and 2022, cases who developed a postoperative lateral ventricle entrapment were retrospectively reviewed and included. Clinical history, imaging and treatment were reported. ResultsAmong 34 patients treated for a colloid cysts, two (5.9 %) patients developed an ipsilateral ventricular entrapment with dilation from two to five months after the resection. Both patients were substantially asymptomatic and neurologically intact, and therefore treated conservatively. One case underwent complete spontaneous radiological resolution one month later, and the other one has remained neurological asymptomatic at follow-up. ConclusionsIsolated asymptomatic ventricular entrapment with significant dilation after endoscopic colloid cyst resection is a rare occurrence which can be plausibly caused by scar tissue at the level of the foramen of Monro. Because they can have an indolent course with spontaneous resolution, conservative treatment is a viable option, with strict radiological and clinical follow – up. Given the rarity of the occurrence, further studies with larger cohorts are warranted to confirm the etiopathogenetic hypothesis and validate the clinical management.

Use of a neuro-evacuation device for the endoscopic removal of third ventricle colloid cysts.

Colloid cysts are benign tumors usually located at the level of the foramen of Monro and account for approximately 1% of all intracranial tumors. Endoscopic surgical treatment represents the approach of choice for removal of these tumors and is usually preferred over transcortical or transcallosal microsurgical approaches. Our purpose is to demonstrate the feasibility of endoscopic removal of colloid cysts using a novel aspiration and fragmentation system, currently designed for evacuation of cerebral hematomas. We performed an evaluation of the results obtained in patients with symptomatic colloid cysts of the third ventricle operated on using an endoscopic neuroevacuation system (Artemis Neuro Evacuation Device, Penumbra, Alameda, California, USA) between April 2020 and April 2022. Instrumentation and surgical technique are described in detail. All patients underwent postoperative MRI to assess the extent of cyst removal. Five patients were included in our study. The predominant symptom at onset was headache. No intraoperative complications related to the technology in use occurred. The surgical time for the cyst removal was significantly shorter than removal via a standard endoscopic technique (80 vs. 120 min). Removal was complete, both content and capsule of the cyst, in all patients. In all cases there was a complete regression of the previously complained symptoms. The Artemis Neuro Evacuation Device has proved to be effective and safe in removal of colloid cysts of the third ventricle and may be proposed as a possible alternative or as a complement of the standard instruments routinely used in neuroendoscopy.

Full-endoscopic removal of third ventricular colloid cysts: technique, results, and limitations.

Colloid cysts (CCs) are rare benign lesions that usually arise from the roof of the third ventricle. They may present with obstructive hydrocephalus and cause sudden death. Treatment options include ventriculoperitoneal shunting, cyst aspiration, and cyst resection microscopically or endoscopically. This study aims to report and discuss the full-endoscopic technique for removing colloid cysts. A 25°-angled neuroendoscope with an internal working channel diameter of 3.1 mm and a length of 122 mm is used. The authors described the technique of resecting a colloid cyst by a full-endoscopic procedure and evaluated the surgical, clinical, and radiological results. Twenty-one consecutive patients underwent an operation with a transfrontal full-endoscopic approach. The swiveling technique (grasping the cyst wall and rotational movements) was used for CC resection. Of these patients, 11 were female, and ten were male (mean age, 41 years). The most frequent initial symptom was a headache. The mean cyst diameter was 13.9 mm. Thirteen patients had hydrocephalus at admission, and one needed shunting after cyst resection. Seventeen patients (81%) underwent total resection; 3 (14%), subtotal resection; and 1 (5%), partial resection. There was no mortality; one patient had permanent hemiplegia, and one had meningitis. The mean follow-up period was 14 months. Even though microscopic resection of cysts has been widely used as a gold standard, successful endoscopic removal has been described recently with lower complication rates. Applying angled endoscopy with different techniques is essential for total resection. Our study is the first case series to show the outcomes of the swiveling technique with low recurrence and complication rates.

Endoscopic Aspiration and Marsupialization for Colloid CYST

Background: Colloid cyst is a benign intracranial tumor found in the anterior third ventricle. Due to location of this tumor, it has propensity to cause obstruction to CSF flow causing hydrocephalus. Treatment options include excision or aspiration of cyst through open or endoscopic procedures or CSF diversion procedures. Recent years have seen a shift towards endoscopic approach to treatment of colloid cyst due to its relative simplicity among endoscopic procedures and other favorable patient related factors. We share our experience with endoscopic aspiration and marsupialization of colloid cyst. Methods: This descriptive retrospective study was done at Neuro surgery department of Neurosurgery, SMBB Institute of Trauma, Dow University of Health Sciences, Dr. Ruth K. M. Pfau Civil Hospital Karachi, Pakistan. Data of patients who had endoscopic aspiration and marsupialization of colloid cyst between February 2017 and October 2020. Patient demographics, clinical presentation, radiological features, operative course and post-operative course was recorded. Clinical or radiologic recurrence was noted on follow-up. Results: Ten patients were operated during the study period. Headache was most common presenting symptom. Mean size of cyst was 21mm. There was incomplete aspiration in 3 patients as observed per-operatively and by residual cyst content on immediate post-operative CT scan which disappeared completely on subsequent scans. CSF leak was observed in 3 patients and 2 developed meningitis. No symptomatic recurrence occurred. Conclusion: Endoscopic aspiration with marsupialization of cyst wall is a safe and effective technique for treatment of colloid cyst. Incomplete aspiration of cyst contents may not require further intervention as the radiological resolution of cyst is observed over time. Further follow-up and larger sample size is needed to further establish the safety and efficacy of this procedure. Keywords: colloid cyst, endoscopic, follow-up studies

Endoscopic versus Microsurgical Resection of Third Ventricle Colloid Cysts: A Single-Center Case Series of 140 Consecutive Patients

Both endoscopic and microsurgery transcortical resection methods are used for colloid cysts of the third ventricle but they have not been compared regarding benefits and pitfalls. Data of patients who underwent surgical resection of third ventricle colloid cyst via either endoscopic or microsurgery approach by a single surgeon from 2005 to 2020 were retrospectively collected. After administration of criteria, 140 records were retrieved (60 patients through endoscopic resection and 80 patients by a transcranial microsurgery approach). Clinical and surgical measures were compared between the 2 types of surgery after adjustment for confounders. Length of hospital stay, postoperative meningitis, operation time, cyst size, and baseline comorbidities were similar between two groups. Gross total resection (GTR) was achieved for all patients in the microsurgery group, whereas in the endoscopic group, resection was lower (90% vs. 100%; P= 0.005). Intraoperative hemorrhage occurred in 14 endoscopic patients (23.3%), whereas for the microscopic group, it was zero (P < 0.001). Postoperative shunt was required for 2 patients (one in the endoscopic group and the other in the microscopic group). Two patients had tumor recurrence, both of whom were in the endoscopic group. No mortality was detected in either group. Multivariate analyses were insignificant for confounding effects of clinical and demographic factors in occurrence of worse surgical outcomes (non-GTR and hemorrhage). In our series, the rate of intraoperative hemorrhage was higher with the endoscopic method and GTR was lower, even after adjustment for other factors. This situation could be caused by technological shortcomings and limited space for resection maneuvers and management of complications.

Acute hydrocephalus caused by a colloid cyst — a case report

BackgroundColloid cysts are rare benign, slowly growing intracranial tumors of endodermal origin. Most colloid cysts are found incidentally and are asymptomatic, but rarely, they can lead to sudden death.Case presentationA 73-year-old female patient was admitted to our emergency department with complaints of dizziness, nausea, vomiting, fatigue, walking difficulties, and behavioral changes. CT imaging revealed acute obstructive hydrocephalus attributable to a third ventricular colloid cyst. The patient was immediately transferred to a tertiary center where she underwent successful neurosurgical resection of the mass. Pathology results of the lesion confirmed the diagnosis of colloid cyst.ConclusionThe case we present emphasizes the critical importance of prompt identification of warning signs, complex thinking, and evaluation. Establishing the right diagnostic approach early on can facilitate accurate diagnosis.

Endoscopic transventricular resection of a colloid cyst

This video demonstrates the purely endoscopic gross-total resection of a third ventricle colloid cyst that is partially covered by a large thalamostriate vein. To gain an ideal approach, the initial trajectory pointed to the interventricular septum above the cyst. After the head of the caudate nucleus is passed, it is retracted laterally by the endoscopic sheath for the ideal far lateral approach to the cyst. Using a pneumatic endoscope holder enables the surgeon to perform the procedure bimanually. After complete removal of the cyst, postoperative inspection confirms the intact fornix, veins, and caudate nucleus without signs of pressure-related damage. The video can be found here: https://stream.cadmore.media/r10.3171/2023.1.FOCVID22140.

Outcomes and complications of microscopic transcallosal colloid cyst resection: A single institution experience.

Colloid cysts have always provoked the interest of neurosurgeons due to their benign histology, wide variety of clinical presentations, and differences in reported surgical outcomes. Although recent studies have reported favorable outcomes with different surgical resection approaches, the transcallosal approach remains the most popular approach to date. In this series, we report the clinical and radiological outcomes of the transcallosal approach for the resection of third ventricle colloid cysts in 12 patients. We present a case series of 12 patients who were radiologically diagnosed with a third ventricle colloid cyst who underwent transcallosal resection by a single surgeon in one center over a 6-year period. Clinical, radiological, and surgical data were collected, and surgical outcomes and complications were analyzed. Of the 12 patients diagnosed with colloid cysts, 10 (83%) presented with headache, and five (41%) presented with memory disturbance. All 12 patients showed improvement or resolution of their symptoms following resection. Nine patients (75%) presented with hydrocephalus on radiology. All the patients required preoperative or intraoperative external ventricular drain insertion. Four patients (33%) experienced transient postoperative complications. None of the patients required long-term cerebrospinal fluids shunting. One (8%) of 12 patients experienced transient memory loss. No mortality was recorded during the follow-up. Transcallosal resection of colloid cysts has a favorable prognosis. It allows for complete resection of the cyst with minimal transient postoperative complications. Most patients with postoperative complications show complete resolution of symptoms, with no long-term morbidity.

Anterior Inter-hemispheric Transcallosal Approach for Resection of Colloid Cyst: A Video Abstract

Abstract Background Although histologically benign, colloid cysts have been an entity of interest to neurosurgeons due to the wide array of possible presentations ranging from asymptomatic to high ICP symptoms to sudden death. It is estimated that colloid cysts represent 0.3 to 2% of all brain tumors.1 As they are typically located in the third ventricle, multiple approaches have been adapted and developed for the maximum resection with the least complications given the sensitive anatomy in the area.1 2 The interhemispheric transcallosal approach can be safely performed to fully resect a third ventricle colloid cyst with close to zero recurrence rate and minimal to none permanent deficits.3 This video is an educational illustration of the surgical technique and the related anatomy for the interhemispheric transcallosal approach and how to provide best chances of a benign postoperative course. Case Description In this surgical video, we present a case of a 20-year-old male, a known case of hypertension and un-controlled diabetes type-1, presented to our hospital with on and off headache, dizziness, and diplopia that gradually progressed. His neurological exam was unremarkable including memory function. CT and MRI scans demonstrated a rounded sharply demarcated lesion at the at the roof of the third ventricle, measuring 1 × 1 cm in size. The patient underwent an anterior inter-hemispheric transcallosal approach, with gross total resection of the cyst. In the follow-up office visit, the patient headache has resolved, and he had no seizures with preserved memory functions. Conclusion When removal of the colloid cyst is indicated, the interhemispheric transcallosal approach can be performed safely with gross total resection and minimal neurological deficit. This is a surgical demonstration of the transcallosal approach showcasing the surgical corridors and related anatomy.

Sudden unexpected death caused by a colloid cyst in the third ventricle: case report

BackgroundColloid cysts arise from congenital abnormalities of the endodermis and are characteristically comprised of an external fibrous layer, with a lining of cuboidal and columnar epithelial cells and endodermal ciliated cells. They contain a gelatinous matrix, produced by mucus-producing epithelial cells.Case presentationAn 8-year-old Saudi girl died in Dammam Central Hospital, to which she was admitted by her parents following her complaints of intense headaches. When the body was examined externally, it was noted that she had bilateral eye congestion, evidence of needle marks on all four limbs and in the region of the femoral triangle and bruising in the central chest and left shoulder areas. No other evidence of injury was noted. A cyst in the third ventricle of the brain was identified at post mortem. Investigations for alcohol, toxins and illicit substances were negative.ConclusionIt was surmised that the child had died as a result of a cerebral colloid cyst and its clinical sequelae.

A Rare Cause of Headache and an Unorthodox Transfer: A Case Report.

Emergency department (ED) crowding and hospital diversion times are increasing nationwide, with negative effects on patient safety and an association with increased mortality. Crowding in referral centers makes transfer of complex or critical patients by rural emergency physicians (EP) more complicated and difficult. We present a case requiring an unorthodox transfer method to navigate extensive hospital diversion and obtain life-saving neurosurgical care. We present the case of a previously healthy 21-year-old male with two hours of headache and rapid neurologic decompensation en route to and at the ED. Computed tomography revealed obstructive hydrocephalus recognized by the EP, who medically managed the increased intracranial pressure (ICP) and began the transfer process for neurosurgical evaluation and management. After refusal by six referral centers in multiple states, all of which were on diversion, the EP initiated an unorthodox transfer procedure to the institution at which he trained, ultimately transferring the patient by air. Bilateral external ventricular drains were placed in the receiving ED, and the patient ultimately underwent neurosurgical resection of an obstructive colloid cyst. First, our case illustrates the difficulties faced by rural EPs when attempting to transfer critical patients when large referral centers are refusing transfers and the need for improvements in facilitating timely transfers of critically ill, time-sensitive patients. Second, EPs should be aware of colloid cysts as a rare but potentially catastrophic cause of rapid neurologic decline due to increased ICP, and the ED management thereof, which we review.

Endoscopic resection of a giant colloid cyst in the velum interpositum: illustrative case.

Colloid cysts are an unusual differential diagnosis for lesions in the lateral ventricles. Microsurgery is usually recommended for the treatment of giant colloid cysts. This case is the largest reported colloid cyst in this unusual location treated with an endoscope. A 39-year-old woman with a history of pulsing headaches presented with nausea, vomiting, vision blurring, and paresthesia of the left leg. On the brain computed tomography, a huge, well-defined homogeneous hyperdense intraventricular lesion with hydrocephalus was observed. Magnetic resonance imaging showed a spherical lesion over the third ventricle inside the lateral ventricles, obstructing the Sylvius aqueduct. There was no enhancement and no diffusion restriction on diffusion-weighted images. Endoscopic third ventriculostomy was undertaken for hydrocephalus treatment. Then the lesion was resected grossly. The cyst wall was resected as much as it was safe. There was no clot or bloody product inside the lesion. Colloid cyst is rarely encountered in the velum interpositum and lateral ventricles, but the authors' giant colloid cyst case along with similar cases led to considering it out of the third ventricle. According to their experience, endoscopic removal is a safe and efficient method for colloid cyst surgery, even in giant cases.

Use of a Neuro-evacuation Device for the Endoscopic Removal of Third Ventricle Colloid Cysts.

Use of a Neuro-evacuation Device for the Endoscopic Removal of Third Ventricle Colloid Cysts.

Practical, Stereotactic, Low-Profile Technique for Transcortical/Transventricular Colloid Cyst Removal Independent of Ventricular Size: Technical Note and Analysis of Approaches.

In the presence of a dilated foramen of Monro, a transcortical, transforaminal approach is considered the safest and simplest approach for resection of colloid cysts. However, in the presence of small or normal frontal horns, numerous microsurgical approaches and, often complicated, variations have been described, invariably employing forms of stereotactic navigation. To report an alternative, accurate, microsurgical stereotactic low-profile technique. The small frontal horn is stereotactically targeted as previously described. Routine equipment is used to accurately create a novel, rigid, atraumatic surgical corridor. After a 7-mm corticotomy, a peel-away catheter carrying the AxiEM stylet engages the target set as the frontal horn. All joints of the endoscope holder are locked, allowing only catheter advancement (y axis) while lateral (x axis) or anteroposterior (z axis) movements are secure. Two, 7-mm retractor blades are inserted. The extremely consistent anatomy of the foramen of Monro allows en bloc microsurgical removal without unnecessary coagulation of cyst wall or choroid plexus. Despite a plethora of approaches to the rostral third ventricle, in the presence of normal or small frontal horns, including creation of transcallosal/interforniceal, suprachoroidal (or transchoroidal), and sub-choroidal, colloid cyst resection does not necessarily need to be convoluted. Technical nuances of an accurate, practical, minimally invasive technique are described.

Endoscopic Approach for Management of Colloid Cyst

Endoscopic Approach for Management of Colloid Cyst

Third Ventricular Colloid Cyst - An Organic Cause of Mania: A Case Report

Background: Psychiatric manifestations due to space-occupying lesions, although not uncommon, are generally misdiagnosed, leading to an unfavorable outcomes. Colloid cyst is a slow-growing, benign tumor in the anterior part of the third ventricle, which frequently presents with neurological complaints like headache and gait disturbances. However, a patient with colloid cyst may also present to the OPD with a spectrum of psychiatric symptoms. Case Report: We here report a middle-aged man who was brought to the OPD with symptoms of pervasive irritability and disinhibited behavior for three months, along with complaints of increased activity, reduced sleep and appetite, suspicious about wife, family members and neighbors. Patient had frequent episodes of headache in the past 3 months associated with nausea, restlessness for which neuroimaging was advised, which showed a hyper-dense lesion in the third ventricle. Patient was referred to neurosurgery and was operated for the same. Post-operatively, family members reported improvement in his behavior. Conclusion: A detailed systemic evaluation for any neurological causes of organic causes or atypical picture of psychiatric conditions is of extreme necessity. There is a dire need for liaison of psychiatrists with neurophysicians and neurosurgeons to attain betterment in patients in both physical as well as psychological aspects, especially in psychiatric diagnosis with organic causes.

PMON100 IgG4 hypophysitis with granulomatous histopathology

Abstract Background IgG4-related disease is characterized by a dense lymphoplasmacytic infiltrate rich in IgG4 plasma cells that may be accompanied by elevated serum IgG4 levels, presence of granulomatous histopathology with multinucleated giant cells has not been reported in patients with IgG4 related hypophysitis.Clinical case: A 39-year-old female with no significant past medical history until April of 2021, when she developed gradual onset of headaches. MRI brain showed a mass in the sella, she was treated for over a month with glucocorticoids by ENT and her headaches improved. She finished the course of glucocorticoids, and soon after, she had a recurrence of her symptoms. Repeat brain MRI revealed a large pituitary mass and she had her first endoscopic endonasal transsphenoidal resection on 8/2021 at an outside hospital. Pathology report of the surgery suggested that she had a colloid cyst of the pituitary and cultures grew actinomyces and streptococcus oralis, likely, as a consequence of contamination from an ethmoid sinus infection/surgical infection, she was treated with antibiotics. Surgery was also complicated by diabetes insipidus for which she is taking desmopressin tablets.She presented to our hospital in November 2021, with persistent symptoms (headaches and worsening vision), and a postoperative brain MRI showing an expansion of the lesion with compression of the optic chiasm, she was evaluated by neurosurgery who recommended repeat revision endoscopic endonasal transsphenoidal resection of this lesion.The patient underwent a second transsphenoidal surgery on 11/29/2021 at our institution. During admission TSH was 0.123 mcIU/ml (0.27-4.2mcIU/ml) with Free T4 0.52ng/dL (0.93-1.7ng/dL). She was discharged on hydrocortisone, desmopressin tablets, and levothyroxine.The pathology report of the second surgery revealed mixed chronic and acute inflammation with granulomatous components containing histiocytic clusters and multinucleated giant cells. Many plasma cells, rare eosinophils, and foci of neutrophils are present. The ratio of IgG4 to IgG is over 70%, with more than 10 IgG4 (+) cells per 10HPF. GMS and AFB were negative for fungi and mycobacteria.Patient's outpatient labs were consistent with panhypopituitarism with AM cortisol of 1.9mcg/dL, ACTH 19pg/mL (6-50 pg/ml), FSH 6.5 mIU/ml, LH 2.4 mIU/ml and estradiol &amp;lt;15pg/ml. TSH was 1.26 mcIU/ml (0.27-4.2mcIU/ml) with Free T4 0.8ng/dL (0.8-1.8ng/dL). IGF-1 level was 72ng/ml (79-259ng/ml). Prolactin was 7.0 ng/ml (3.0-30.0ng/ml). IgG4 serum level was 100.2mg/dL (4.0-86.0mg/dL), IgG1 serum level was 446mg/dL (382-929mg/dL). Conclusion This is a unique patient with panhypopituitarism that meets the criteria for IgG4 related hypophysitis but also has secondary granulomatous components developed after the rupture of the colloid cyst during the first surgery. The implications of these findings are unknown in terms of management and prognosis. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

PSAT286 A Rare Case of Papillary Thyroid Cancer of the Thyroglossal Duct Cyst with Benign Thyroid

Abstract Introduction While the thyroglossal duct cyst (TGDC) is the most commonly seen midline neck mass, thyroglossal duct cyst carcinoma is rare (1-2%) with only a few hundred cases published in the literature. The disease can be challenging to diagnose and treat because most TGDC carcinoma are diagnosed post-operatively and data is limited regarding the extent of surgical resection, adjuvant therapy and long-term outcomes. We report a case of papillary thyroid carcinoma arising from TGDC without any evidence of disease in the thyroid gland. Case Report A 31-year-old male presented with complaints of progressively worsening dysphagia and weight loss for 4 months. An initial CT neck with contrast revealed a soft tissue mass along the anterior aspect of the thyroid cartilage measuring 3.4×2.0×2.2 cm that extended anteriorly from the base of the tongue, favoring a thyroglossal duct cyst. The thyroid gland appeared normal on this imaging. He was given a 2-week course of antibiotics and pantoprazole with no improvement in his symptoms. He underwent a thyroid ultrasound, which showed a large hypoechoic mass, partially cystic, anterior to thyroid. FNA of the TGDC was suspicious for papillary thyroid cancer. Follow-up CT scan redemonstrated known TGDC with increased size of adjacent lymph nodes, concerning for metastasis. Given FNA results, regional lymph node involvement, and the patient's symptoms, he underwent successful Sistrunk procedure for TGDC removal. He declined to wait for intraoperative frozen pathology and opted to discuss pathology and next steps after surgery. Pathology of the TGDC confirmed papillary thyroid cancer (conventional type) with uninvolved margins and metastasis to one of four lymph nodes with the largest lymph node being 7 mm. At the tumor board conference, it was recommended he further undergo a total thyroidectomy with possible post-operative radioactive iodine (RAI) treatment. He underwent a total thyroidectomy, and pathology showed benign thyroid gland with a few colloid cysts. Post-operatively, he was started on levothyroxine. He did not have any improvement in dysphagia following both surgeries. After extensive discussion of the risks and benefits of RAI, the patient chose to defer RAI treatment until further evaluation of his dysphagia was completed. Ultimately, the decision was made to monitor with serial ultrasounds and thyroglobulin levels. Conclusion Optimal treatment of TGDC carcinoma is debatable. A Sistrunk procedure involving resection of cyst plus mid-portion of hyoid bone is universally recommended for adequate excision of the cyst. However, no clear consensus guidelines exist for further management with total thyroidectomy and/or post-operative RAI. Total thyroidectomy permits excision of unsuspected thyroid carcinomas and enables a better follow-up. However, decisions can vary based on extent of disease, tumor characteristics, demographics, and patient preferences. Management decisions should be made on an individualized basis, using a multidisciplinary and shared decision-making approach. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

On Natural History and Management of Colloid Cysts: Time to Rethink?

Colloid cysts, although benign, may occasionally cause obstructive hydrocephalus and sudden death. Reliable prognostic factors for symptomatic progression have been sought, with heterogenous results. We conducted a retrospective review of all cases of colloid cysts of the third ventricle managed at our center between 2009 and 2019. Clinical and neuroimaging characteristics were analyzed using logistic regression in relation to symptomatic status and hydrocephalus. The cutoff values for outcome prediction were calculated using the receiver operating characteristic curve analysis. There were 82 patients with colloid cysts, of whom 60 were asymptomatic and 22 symptomatic. None of the asymptomatic patients experienced acute neurologic decline or hydrocephalus during follow-up, whereas half (n= 11) of the symptomatic patients presented with hydrocephalus, 8 of whom had acute hydrocephalus. We found 3 putative candidate risk factors for symptomatic colloid cysts: T1-weighted magnetic resonance imaging hyperintense/mixed signal appearance (P= 0.004), location in risk zone I (P= 0.007), and a volume >236.49 mm3 (P= 0.007). Cyst diameter and volume/foramen of Monro diameter ratios had a decreasing trend over time among asymptomatic patients, providing new insights into the natural history of the disease. Only a few asymptomatic colloid cysts showed progression requiring surgery, with no acute deterioration or fatal events, whereas the rest remained stable over time, thus supporting a more conservative approach for this group of patients. Higher risk for developing symptomatic colloid cyst was defined by a risk score that included T1-weighted magnetic resonance imaging appearance, risk zone, and colloid cyst volume, aiding the detection of patients at risk of clinical deterioration.

Spontaneous regression of colloid cyst on the third ventricle: a case report with the review of the literature

BackgroundColloid cyst (CC) is a rare and benign cyst found in the third ventricle near the foramen of Monro. Although the role of surgical resection is well established in symptomatic large-sized CC, it remains debatable whether surgical removal of CC with no symptoms or minimal symptoms is necessary.Case presentationA 49-year-old male patient visited our institute for incidentally detected intracranial mass. MRI demonstrated typical, 12 mm-sized CC located in the third ventricle. It was noticed that the cyst spontaneously decreased in size from 12 mm to 4 mm on MRI at 18 months after the first visit.ConclusionAlthough spontaneous regression is a very rare phenomenon in CC, regular imaging study and frequent neurologic examination can be an alternative option for well-selected, asymptomatic cases.