Role of Magnetic Resonance Imaging in the Evaluation of Trigeminal Neuralgia Using Steady-State Imaging.

Trigeminal neuralgia (TN) poses diagnostic challenges due to its complex origins, often associated with neurovascular compression. Advanced imaging techniques, particularly magnetic resonance imaging (MRI) with the fast imaging employing steady-state acquisition (FIESTA) sequence, offer crucial insights into TN pathophysiology. This prospective cross-sectional observational study aimed to elucidate MRI's utility in diagnosing TN and correlating imaging findings with clinical manifestations and treatment outcomes. A cohort of 41 patients clinically suspected of TN underwent MRI evaluation at Acharya Vinoba Bhave Rural Hospital, Sawangi (Meghe), Wardha, utilizing various sequences including FIESTA. Analysis revealed a higher incidence among females, predominant unilateral presentation, and a higher prevalence of abnormal MRI findings, with neurovascular compression as the leading etiology. Correlation analysis demonstrated significant associations between facial pain localized to the trigeminal nerve distribution, triggering factors, and abnormal MRI findings. Gender distribution did not significantly influence MRI findings. Treatment outcomes favored microvascular surgery over conservative management in cases of neurovascular compression. This study underscores MRI's pivotal role, particularly FIESTA, in TN evaluation, guiding personalized treatment strategies and emphasizing the importance of integrated clinical and imaging approaches. Further research is warranted to validate these findings and explore additional imaging modalities for a deeper understanding of TN pathogenesis.

Evaluation of the correlation between trigeminal nerve atrophy and trigeminal neuralgia using multimodal image fusion: A single-center retrospective study.

BACKGROUND: 3D-Slicer is an open-source medical image processing and visualization software. In the surgical treatment of trigeminal neuralgia, it is commonly used to predict the responsible vessels. However, there are few reports on the use of 3D-Slicer software to quantitatively measure the bilateral trigeminal nerve volume in patients with primary trigeminal neuralgia (PTN) based on the three-dimensional images. Therefore, this study aims to explore the role of three-dimensional fused images processed by 3D-Slicer in the evaluation of trigeminal nerve atrophy, providing an objective basis for the diagnosis of PTN. METHODS: 57 PTN patients who underwent microvascular decompression (MVD) or percutaneous balloon compression (PBC) surgery in Hebei general hospital between January 2020 and April 2023 were included. Additionally, 30 patients with facial spasms(HFS) were included as a control group. All patients underwent 3D-TOF-MRA and 3D-FIESTA sequence examinations. Comparisons of bilateral trigeminal nerve volumes within and between groups were conducted by performing image fusion using 3D-slicer. RESULTS: The volume of the affected trigeminal nerve in the MVD group (33.96 mm³±12.61 mm³) and PBC group (23.05 mm³±7.71 mm³) was smaller than that of the unaffected trigeminal nerve in the MVD group (39.61 mm³±12.83 mm³) and PBC group (26.14 mm³±6.42 mm³), as well as the average volume of the trigeminal nerve in the control group (40.27 mm³±10.25 mm³) (P<0.05). The differences in bilateral trigeminal ganglion volume (∆V) was significant between the MVD group (∆V=23.59 %±14.32 %) and the control group (∆V=14.64 %±10.00 %) (P<0.05). There was no statistical difference in the trigeminal nerve volume difference between the MVD group (∆V=23.59 %±14.32 %) and the PBC group (∆V=26.52 %±15.00 %) (P>0.05). CONCLUSION: Trigeminal nerve atrophy is correlated with primary trigeminal neuralgia. 3D-slicer software can quantitatively measure trigeminal nerve volume and assist in the diagnosis of primary trigeminal neuralgia based on the difference in bilateral trigeminal nerve volumes. However, trigeminal nerve atrophy is not associated with postoperative pain recurrence in patients.

Incidental durotomy resulting in a postoperative lumbosacral nerve root with eventration into the adjacent facet joint: illustrative cases.

BACKGROUND: Radicular pain after lumbar decompression surgery can result from epidural hematoma/seroma, recurrent disc herniation, incomplete decompression, or other rare complications. A less recognized complication is postoperative nerve root herniation, resulting from an initially unrecognized intraoperative or, more commonly, a spontaneous postoperative durotomy. Rarely, this nerve root herniation can become entrapped within local structures, including the facet joint. The aim of this study was to illustrate our experience with three cases of lumbosacral nerve root eventration into an adjacent facet joint and to describe our diagnostic and surgical approach to this rare complication. OBSERVATIONS: Three patients who had undergone lumbar decompression surgery with or without fusion experienced postoperative radiculopathy. Exploratory revision surgery revealed all three had a durotomy with nerve root eventration into the facet joint. Significant symptom improvement was achieved in all patients following liberation of the neural elements from the facet joints. LESSONS: Entrapment of herniated nerve roots into the facet joint may be a previously underappreciated complication and remains quite challenging to diagnose even with the highest-quality advanced imaging. Thus, clinicians must have a high index of suspicion to diagnose this issue and a low threshold for surgical exploration.

Racemose neurocysticercosis: a case series.

Neurocysticercosis (NCC) is a common parasitic condition of the central nervous system in certain parts of the world. The racemose variety of NCC is distinct from the commonly seen parenchymal form. It frequently infiltrates the basal cisterns and Sylvian fissures. Imaging plays a vital role in the diagnosis; however, as their signal intensity is similar to cerebrospinal fluid and due to the absence of enhancement in most cases, imaging diagnosis is often difficult on the conventional MRI sequences. Here, we present five cases of racemose NCC to emphasize the importance of a heavily T2-weighted sequence (Fast Imaging Employing Steady-state Acquisition) sequence in the diagnosing this entity.

Correlation of Preoperative High-Resolution Neurovascular Imaging and Surgical Success in Neurovascular Compression Syndromes.

BACKGROUND: Neurovascular compression syndromes (NVCSs) are a group of neurological disorders characterized by compression of a cranial nerve and include trigeminal neuralgia (TN), hemifacial spasm, geniculate neuralgia, glossopharyngeal neuralgia, vestibular paroxysmia, and trochlear palsy. The European Academy of Neurology recommends constructive interference in steady-state/fast imaging employing steady-state (CISS/FIESTA) magnetic resonance imaging (MRI) in the evaluation of medically intractable TN, but similar recommendations do not exist for the remaining NVCSs. METHODS: We conducted a retrospective chart review of 300 patients with an NVCS who underwent microvascular decompression (MVD) by a single neurosurgeon from 2004 to 2021. Data were collected on preoperative diagnosis, pre- and postoperative symptoms, presence/absence of preoperative high-spatial-resolution CISS/FIESTA MRI, and intraoperative findings. Rates of symptomatic improvement were used as a correlate of surgical success. RESULTS: The rate of symptomatic improvement in the patients with a preoperative CISS/FIESTA MRI was 5.8% greater than those without preoperative high-spatial-resolution neuroimaging (98.8% vs. 93%, respectively; P = 0.008). Stratified by diagnosis, patients with TN had the greatest difference in surgical success between the 2 groups (99.3% vs. 92.9%, n = 268; P = 0.006). No statistically significant differences were observed in the other NVCSs, although positive trends were noted. CONCLUSIONS: Preoperative CISS/FIESTA MRI correlated with greater rates of surgical success in cases of medically intractable TN; however, definitive conclusions could not be made regarding the remaining NVCSs. We support the recommendation that this imaging modality be included as part of the standard of practice for the evaluation and management of TN and encourage future studies to further elucidate this relationship for the less common NVCSs using a larger cohort.

Bridge technique for hemifacial spasm with vertebral artery involvement: 2-Dimensional operative video.

Microvascular decompression for hemifacial spasm (HFS) associated with the vertebral artery (VA) is more challenging than that for small arteries. Atherosclerotic VA and tortuous VA are associated with a low success rate and high incidences of complications. Artery relocation employing a Teflon sling is helpful for small arteries. However, a different decompression technique should be considered in VA-related HFS due to the stiffness of the offending artery. With our simple decompression technique providing a secure transposition that can be performed even in the narrow cistern, a rigid Teflon bar is inserted to hold up all offending vessels between the pontine surface and the cerebellar flocculus (the bridge technique). This simple technique easily creates a free space over the root entry zone (REZ), reduces surgical manipulation compared to conventional artery relocation with a Teflon sling, and provides more secure nerve decompression than inserting Teflon pledgets on the REZ. The critical factors for successfully performing the bridge technique are using a rigid Teflon bar that can hold the rebound force of the VA and a length appropriate to generate a free space over the REZ between the pons and the cerebellar flocculus. In this video, we demonstrate our bridge technique for VA-related HFS and discuss the advantages and disadvantages of this novel approach.

Intracochlear signal in FIESTA-C and hearings of patients with cerebellopontine angle schwannoma.

BACKGROUND: Hearing loss in patients with cerebellopontine angle (CPA) schwannoma, is thought to be caused by the damage to the cochlea and the cochlear nerve. AIM: This study aimed to examine the relationships between the intracochlear signal in magnetic resonance imaging (MRI) and hearing in patients with CPA schwannoma. MATERIAL AND METHOD: In 79 patients with CPA schwannoma, we retrospectively examined the signal in the cochlea on the affected side was compared with that on the unaffected side to determine signal degradation in fast imaging reagents steady-state acquisition with cycle phases (FIESTA-C) MRI. For hearing evaluation, pure tone audiometry (PTA), speech audiometry, distortion product otoacoustic emissions (DPOAE), and auditory brainstem response (ABR) were used. For each parameter, we examined the differences between the groups with and without signal degradation. RESULTS: In the hearing test results, the I-wave latency of ABR was significantly longer in the group with signal degradation in FIESTA-C (1.84 ± 0.35 msec vs. 2.04 ± 0.37 msec, p = 0.048). There was no statistically significant difference in other tests. CONCLUSION: The MRI signal changes in the cochlear were related to the I-wave latency of ABR and reflected cochlear function. SIGNIFICANCE: We suggested the cochlear signal changes in CPA schwannoma patients related the hearing.

A Combination of 3D TOF MRA and FIESTA Predicts Surgery-Needed Primary Trigeminal Neuralgia and Specific Offending Vessels.

BACKGROUND: To investigate the predictive accuracy of three-dimension (3D) time-of-flight (TOF) MR angiography (MRA) and 3D Fast Imaging Employing Steady-state Acquisition (FIESTA) techniques in assessing neurovascular compression (NVC) with specific vessels in patients with primary trigeminal neuralgia (TN). METHODS: Patients with single-site primary TN undergoing microvascular decompression (MVD) were retrospectively recruited. All patients had available preoperative magnetic resonance imaging (MRI) scans. A quantitative NVC scoring system was applied to assess the severity of NVC on MRI. The radiological findings were correlated with the intraoperative result to determine the diagnostic accuracy of MRI techniques. Besides, the radiological indicator of MVD was determined. RESULTS: Seventy-three TN patients were recruited. Thirty-three patient had bilateral NVC but with unilateral neuralgia. The average NVC score of the asymptomatic side was significantly lower than that of the symptomatic side (1.6 vs. 6.7; p < 0.001). A cut-off value of NVC >4 was determined as a radiological indicator of MVD with sensitivity and specificity of 82.2% and 98.6%, respectively Area Under Curve (AUC = 0.97; p < 0.001). Approximately 90% of symptomatic patients had the distance to REZ ≤3 mm. 68.5% of patients had a single conflicting vessel, and superior cerebellar artery (SCA) was the predominate vessel (46.6%). The sensitivity and specificity of MRI to detect NVC were 95.8% and 100%, respectively. Regarding each vessel, the cohen's kappa statistic (K) was 0.632 overall. CONCLUSIONS: 3D TOF MRA and FIESTA show an overall good ability to predict specific offending vessels. NVC score >4 is identified to predict TN, suggestive of subsequent surgical treatment.

Association of Cerebellar Tonsil Dynamic Motion and Outcomes in Pediatric Chiari I Malformation.

OBJECTIVE: Chiari I malformation (CM-1), traditionally defined as a descent of the cerebellar tonsils by 5 mm or more, is surgically managed via posterior fossa decompression. However, there is currently no clear radiologic or symptomatic selection criteria for surgical intervention to indicate which patients may see the most improvement following decompression. METHODS: This retrospective pilot study included 22 patients who had symptomatic CM-1 managed via surgical decompression and 22 patients who had nonoperative management of CM-1. Tonsillar motion was assessed using phase-contrast magnetic resonance imaging and 2-dimensional fast imaging employing steady-state acquisition. Both quantitative and qualitative results that best described the CM-1 anatomy, radiologic measurements, and tonsillar motion were obtained and analyzed. RESULTS: Statistical analysis suggested that clinical symptoms differ based on tonsillar motion (P = 0.0044). Surgical patients had significantly more tonsillar motion than nonsurgical patients (P = 0.0010). Among the patients who underwent suboccipital decompression, the presurgery to postsurgery change in clinical symptoms was statistically significant (P < 0.0001), with all clinical symptoms showing decreased prevalence postsurgery. Anterior flow (P = 0.0004) and posterior flow (P < 0.0001) had significant negative associations with tonsillar motion. CONCLUSIONS: Tonsillar motion correlated positively with increased clinical symptoms of CM-1. Furthermore, tonsillar motion was associated with impaired cerebrospinal fluid flow that manifested in increased clinical symptoms. We recommend use of 2-dimensional fast imaging employing steady-state acquisition and assessment of cerebrospinal fluid flow as an adjunct to both clinical judgement and magnetic resonance imaging when selecting patients with CM-1 who would best benefit from surgical decompression.

Prognostic value of long-term antidiabetic and antihypertensive therapy in postoperative gastric cancer patients: the FIESTA study.

BACKGROUND: Gastric cancer is often comorbid with hypertension and diabetes mellitus and increases the mortality risk. MATERIALS AND METHODS: We conducted this prospective cohort study to investigate antidiabetics and antihypertensives' impact on gastric cancer survival. 3012 patients with gastric carcinoma undergoing radical gastrectomy were enrolled since January 2000 and followed up until July 2020. RESULTS: Hypertension and diabetes patients had worse survival than patients without hypertension and diabetes [median survival time (MST): 48 versus 112.5 months, p < 0.001 for hypertension, MST: 32.7 versus 183+ months, p < 0.001 for diabetes]. Compared to untreated patients, treated patients had better survival (MST: 109.7 months versus 39.1 months, p < 0.001 for antihypertensives, MST: 120.9 months versus 22.3 months, p < 0.001 for antidiabetics). Antihypertensives and antidiabetics were related to 42% (HR 0.58, 95% CI 0.47-0.73, p < 0.001) and 70% (HR 0.30, 95% CI 0.24-0.38, p < 0.001) reduced mortality risk relative to those without medications. metformin and Calcium channel blockers can better-improved prognosis compared to others (p = 0.00029 and p = 0.015). CONCLUSION: Post-surgical gastric cancer patients could benefit substantially from anti-diabetes and antihypertensive therapy. Metformin and Calcium channel blockers may be superior to other medications.

Prospective comparative analysis for application and selection of FIESTA sequence and SSFSE sequence in MRI for prenatal diagnosis of placenta previa accreta.

Placenta previa accreta patients were examined using fast-imaging employing steady-state acquisition (FIESTA) and single-shot fast spin echo (SSFSE) sequence. The diagnostic value of the two sequences was compared. FIESTA was better than the SSFSE sequence in displaying outline-boundary (excellent: 82 vs. 26), signal-to-noise ratio (excellent: 75 vs. 54) for placenta and uterus. The direct signs detection rate in FIESTA was higher than SSFSE (implantable: P = .028, adhesive: P = .131, penetrating type: P = .326). The indirect signs detection rate in FIESTA was lower than SSFSE (low-signal density: P = .029, uneven-signal density: P = .328, thicker and more vascular shadow: P = 398). FIESTA combining SSFSE demonstrated higher detecting rates (100% for sensitivity, specificity, and accuracy) for all types than single sequence scanning (FIESTA/SSFSE). In conclusion, FIESTA clearly showed the situation of the placenta and uterus in placenta previa accreta patients, with excellent image quality. A combination of FIESTA and SSFSE can improve the diagnostic value of placenta previa accreta.Important statementWhat is already known on this subject? Placenta previa is the most common cause of vaginal bleeding in the third trimester of pregnancy.What do the results of this study add? FIESTA was better than the SSFSE sequence in displaying images and demonstrated higher detection rates for direct signs and lower detection rate comparing the SSFSE sequence. FIESTA combining SSFSE sequence demonstrated higher detecting rates for implantable, adhesive and penetrating types than single sequence scanning.What are the implications of these findings for clinical practice and/or further research? FIESTA sequence clearly showed the situation of placenta and uterus in placenta previa accreta patients, with excellent image quality. Combination of FIESTA and SSFSE sequences can effectively improve the diagnostic value of placenta previa accreta.

Mechanical thrombectomy in acute stroke for superior limb of the fenestration of the middle cerebral artery.

Fenestration of the middle cerebral artery (MCA) is a rare anatomic variant, and lenticulostriate arteries (LSAs) often arise from the superior limb of the fenestrated segment. A case of acute occlusion of the superior limb of a fenestrated MCA that successfully underwent mechanical thrombectomy is presented. Digital subtraction angiography performed for a 73-year-old man with acute left hemiparesis showed poor visualization of the upper half of the right M1 segment with maintenance of antegrade peripheral circulation of the MCA territory, and mechanical thrombectomy was successfully performed using a stent retriever with intravenous thrombolysis. After restoration of the MCA, the vascular variant of a fenestrated MCA was found. Clinicians must consider the possibility of acute occlusion of a fenestrated MCA before endovascular thrombectomy. Restoration of acute occlusion of the upper limb of a fenestrated MCA can avoid LSA territory infarction.

Dynamic Fast Imaging Employing Steady State Acquisition Magnetic Resonance Imaging of the Vocal Tract in One Overtone Male Singer: Our Preliminary Experience.

AIMS: To demonstrate physiological changing of vocal tract's structures during overtone singing with commercial magnetic resonance imaging (MRI) Fast Imaging Employing Steady State Acquisition (FIESTA) dynamic sequence. METHODS AND MATERIALS: A 1.5 T MRI with a 16 channel head-and-neck coil and a FIESTA sequence were used. A temporal resolution of 0.155 sec (7 image/s). A single professional singer was studied. The MR acquisition is made while the singer performed a predetermined singing sequence. Three different overtone singing techniques were examined (L-technique, J-technique, and NG technique) and one effect (Ezengileer) applied to L-technique. For each overtone technique we evaluated MRI movement of lips, tongue, velopharyngeal closure, and relationship among tongue and pharyngeal posterior wall/soft palate. To cancel the noise over-imposed, the dynamic MRI was subsequently dubbed in studio with the audio of the preset overtone sing. Dubbed MR images were analyzed with an Overtone Analyzer Software and different sound frequencies were identified and pointed out as colored lines. RESULTS: This study shows that different overtone techniques are related to a specific conformation of tongue, lips, soft and hard palate and motion's relation changing between them. Only a correct conformation of vocal tract's structure allows resonance and so to hear desired fundamental and harmonic pitch in overtone singing. CONCLUSION: The preliminary data of our study demonstrates that FIESTA dynamic MRI sequence can be used to depict changing of position of vocal tract's structure in overtone singing techniques with a good temporal and anatomic resolution.

Usefulness of three-dimensional fast imaging employing steady-state acquisition MRI of large vessel occlusion for detecting occluded middle cerebral artery and internal carotid artery before acute mechanical thrombectomy.

OBJECTIVE: Acute mechanical thrombectomy (AMT) in patients with acute ischemic stroke from large vessel occlusion (LVO) is performed without directly identifying the occluded vessels. In this study, we evaluated whether 1.5 T magnetic resonance imaging (MRI) with 3D-fast imaging employing steady-state acquisition (FIESTA) could visualize the occluded intracranial middle cerebral artery (MCA) and internal carotid artery (ICA) before AMT. METHODS: This retrospective study included 21 consecutive patients who underwent time-of-flight magnetic resonance angiography (TOF MRA) and 3D-FIESTA MRI immediately before AMT. The patients also underwent TOF MRA after AMT and achieved TICI 2b or 3 by AMT at our hospital between February 2018 and April 2019. When LVO in the anterior circulation was detected by TOF MRA, 3D-FIESTA MRI was additionally performed. Then, the occluded intracranial MCA and ICA, including their branches, were constructed on the workstation with volume rendering. The obtained images were fused with the TOF MRA images to create combined 3D images. RESULTS: The length and top-to-bottom distance of the affected M1 segment (calculated by the ipsilateral-to-contralateral ratio) were 1.29 and 1.17, respectively, on 3D-FIESTA MRI before AMT and 1.34 and 1.24, respectively, on TOF MRA after AMT. We assessed the number of M2 segments branching from the affected M1/M2 junction and visualized the affected anterior temporal artery. The 3D-FIESTA MRI before AMT and TOF MRA after AMT were consistent in all patients, except for two who moved vigorously during imaging. CONCLUSIONS: Images acquired by 1.5T 3D-FIESTA MRI can visualize to predict the existing path of the occluded MCA and ICA before AMT in patients with LVO of the anterior circulation.

Gunshot-Related Pediatric Left Ventricular Apical Aneurysm.

Penetrating injuries of the thorax and abdomen, such as gunshot and stabbing, are rare in children. We present the case of a pediatric patient with a history of remote gunshot injury presenting with a late aneurysm in the left ventricle. (Level of Difficulty: Intermediate.).

The use of FIESTA sequence MRI in successful management of abdominal pregnancy.

Identification of fetal location and its relations to abdominal organs is extremely important in reducing fetal and maternal morbidity in rare cases of abdominal pregnancy. Ultrasound examination is inadequate for helping to successfully manage such cases. In this case report, FIESTA sequence MRI is used to provide high-resolution, better contrast, and higher signal-to-noise ratio fetal and abdominal images. A case of advanced abdominal pregnancy with a live fetus is reported. The surgery was conducted successfully on 34 weeks of gestation.

An MRI study of the tibial nerve in the ankle canal and its branches: a method of multiplanar reformation with 3D-FIESTA-C sequences.

BACKGROUND: The visualization of the tibial nerve and its branches in the ankle canal is helpful for the diagnosis of local lesions and compression, and it is also useful for clinical observation and surgical planning. The aim of this study was to investigate the feasibility of three-dimensional dual-excitation balanced steady-state free precession sequence (3D-FIESTA-C) multiplanar reformation (MPR) display of the tibial nerve and its branches in the ankle canal. METHODS: The subjects were 20 healthy volunteers (40 ankles), aged 22-50 years, with no history of ankle joint disease. The 3D-FIESTA-C sequence was used in the 3.0 T magnetic resonance equipment for imaging. During scanning, each foot was at an angle of 90° to the tibia. The tibial nerve of the ankle canal and its branches were displayed and measured at the same level through MPR. RESULTS: Most of the tibial nerve bifurcation points were located in the ankle canal (57.5%), few bifurcation points (42.5%) were located at the proximal end of the ankle canal, and none of them were found away from the distal end. The bifurcation between the medial plantar nerve and the lateral plantar nerve was on the line between the tip of the medial malleolus and the calcaneus, and it's angle ranged between 6° and 35°. In MPR images, the display rates of both the medial calcaneal nerve and the subcalcaneal nerve were 100%, and the starting point of the subcalcaneal nerve was always at the distal end of the starting point of the medial calcaneal nerve. In 55% of cases, there were more than two medial calcaneal nerve innervations. CONCLUSION: The 3D-FIESTA-C MPR can display the morphological features and positions of the tibial nerve and its branches and the bifurcation point's projection position can be marked on the body surface. This method not only benefited the imaging diagnosis of the tibial nerve and branch-related lesions in the ankle canal, but it also provided a good imaging basis to plan a clinical operation of the ankle canal and avoid surgical injury.

Stereotactic surgery for neurocysticercosis of the 4th ventricle: illustrative cases.

BACKGROUND: Neurocysticercosis, caused by the larval stage of Taenia solium, affects the cerebral ventricles in 20-30% of cases and may lead to hydrocephalus and other neurological morbidity. Conventional treatment for cysts in the 4th ventricle includes open surgery (suboccipital approach) and neuroendoscopy, with the latter being the option of choice. Stereotactic surgery, minimally invasive, offers a good alternative for this type of deep lesion. OBSERVATIONS: The authors report the cases of two women, 30 and 45 years old, who presented with headache, dizziness, and ataxia and were diagnosed with 4th ventricle cysticercosis. Magnetic resonance imaging (MRI) revealed dilated 4th ventricles (approximately 2.5 cm in both cases, with cystic images inside the ventricular cavity). Both patients were treated with stereotactic surgery via a suboccipital transcerebellar approach. Cyst material was extracted, and the diagnosis was confirmed by pathological examination. The surgeries had no complications and resulted in clinical improvement. Control MRI scans showed reduction of the volume of the ventricle without residual cysts. LESSONS: Minimally invasive stereotactic surgery provided a safe alternative for 4th ventricle neurocysticercosis cysts, with more benefits than risks in comparison with conventional techniques.

Secondary Chiari malformation due to enlarged spinal arachnoid villi-like structure: illustrative case.

BACKGROUND: Secondary Chiari malformation can be caused by various disorders associated with cerebrospinal fluid (CSF) leakage at the spinal level. In this report, the authors describe a rare case of secondary Chiari malformation caused by excessive CSF absorption through the enlarged spinal arachnoid villi-like structure. OBSERVATIONS: A 20-year-old woman presented with progressive severe headache and posterior neck pain. Magnetic resonance imaging showed tonsillar herniation and decreased subarachnoid space around the spinal cord. A hypointense signal area was observed in the ventral spinal canal on a T2-weighted image. An axial image revealed multiple small, arachnoid cyst-like structures at the right T1 nerve root sleeve. Direct surgery revealed that the cyst-like structures were continuous with the arachnoid membrane and protruded into the abnormally large epidural venous sinus. The cyst-like structures were resected, and the dural sleeve was repaired using fascia. The patient showed good improvement of symptoms after surgery. LESSONS: Excessive CSF absorption through the enlarged spinal arachnoid villi-like structure can cause secondary Chiari malformation. Neurosurgeons should be aware of this unusual mechanism of CSF leakage. Simple posterior fossa decompression will be ineffective or even harmful.

Endoscopic endonasal surgery for massive subarachnoid neurocysticercosis: illustrative case.

BACKGROUND: Subarachnoid neurocysticercosis (NCC) is associated with high morbidity and mortality rates. Conventional transcranial approaches and transventricular endoscopy have been previously reported for extraparenchymal NCC and ventricular NCC, respectively. By October 2019, endonasal endoscopic approaches had not been used for the treatment of NCC. OBSERVATIONS: A 54-year-old-woman with NCC was admitted with acute neurological deterioration due to severe intracranial hypertension caused by massive subarachnoid NCC cysts, as evidenced on magnetic resonance imaging (MRI) with great brainstem compression. The case was discussed, and an endoscopic endonasal resection of the NCC cysts was scheduled. The diagnosis was confirmed by pathological anatomy. There were no complications in the surgery, with marked neurological improvement. Control MRIs demonstrated a significant reduction of NCC cysts. LESSONS: Minimally invasive approaches are an excellent alternative for skull-base tumoral and infectious pathology. Prior knowledge of the pathophysiology and the authors' experience in the management of patients with NCC allowed them to propose this approach, with optimal results.