Microsurgical Resection of a Parachiasmatic Craniopharyngioma via a Left-Sided Pterional Transsylvian Approach.

Craniopharyngiomas are histologically benign tumors that originate from squamous rests along the pituitary stalk. They make up approximately 1.2% to 4.6% of all intracranial tumors and do not show significant differences in occurrence based on sex. Adamantinomatous craniopharyngiomas have 2 peaks of incidence, commonly observed in patients from ages 5 to 15 years and again from 45 to 60 years. In contrast, papillary craniopharyngiomas mainly affect adults in their fifth and sixth decades of life.1 The "malignancy" of craniopharyngiomas is attributed to their location and the challenges associated with achieving complete removal because they can manifest in the sellar, parachiasmatic, and intraventricular regions or a combination of these.2,3 Various approaches have been used to resect these tumors.4,5 Radical resection offers the most promising option for disease control, potential cure, and the ability to transform the disease from lethal to survivable in children, allowing for a functional adult life.2,3 Meticulous evaluation is crucial to determine the appropriate approach and side, with particular emphasis on closely examining the relationship between the tumor and optic pathways (nerve, chiasm, tract), which are frequently involved. This assessment should also include the tumor's relationship with other crucial structures, such as the hypothalamus and adjacent arteries, to ensure that the strategy is adjusted accordingly to further minimize the risk of postoperative morbidity. Video 1 demonstrates a left-sided pterional transsylvian approach to remove a parachiasmatic craniopharyngioma involving the left optic chiasm and tract.

Prechiasmatic Transection of the Unilateral Dodge Class â Optic Pathway Glioma without Neurofibromatosis Type 1: Technical Description and Clinical Prognosis.

OBJECTIVE: For unilateral Dodge Class Ⅰ optic pathway glioma (OPG-uDCⅠ) without neurofibromatosis type 1, unilateral isolated optic nerve gliomas before the optic chiasm have been confirmed to possibly cause visual deterioration and poor prognosis. For this type of highly selective localized tumor, we explored surgery as the only treatment method. This article retrospectively analyzed and summarized the clinical data of this case series, with the aim of exploring the main technical details and clinical prognosis. METHODS: Included were patients with OPG-uDCⅠ without neurofibromatosis type 1 and experiencing vision loss on the affected side. The fronto-orbital approach was used, which was mainly divided into 3 parts: intraorbital, optic canal, and intracranial. All patients underwent prechiasmatic resection without any adjuvant treatments. The follow-up period was 3 months after surgery, and magnetic resonance imaging and contralateral visual acuity were reviewed annually after surgery. RESULTS: All OPG-uDCⅠ cases were completely removed without any adjuvant treatments, and there was no recurrence during the follow-up period. Pathological results showed that, except for 1 adult patient with pilomyxoid astrocytoma (World Health Organization grade Ⅱ), the others all had pilocytic astrocytoma (World Health Organization grade Ⅰ). Five patients experienced transient ptosis, and all recovered 3 months after surgery. CONCLUSIONS: For OPG-uDCⅠ without neurofibromatosis type 1, radical prechiasmatic resection of the tumor is possible, without the need for postoperative radiotherapy and chemotherapy.

Investigation of Demyelination and Remyelination Processes of the Compressed Optic Chiasm: An Experimental Model.

AIM: To demonstrated demyelination and remyelination of the optic nerve histologically by electron microscopy in an experimental model similar to the compression of pituitary adenomas on the optic chiasm. MATERIAL AND METHODS: The rats were fixed to a stereotaxic device under deep anesthesia, and a balloon catheter was placed under the optic chiasm through a burr hole which was in front of the bregma in accordance with the brain atlas of rats. The animals were divided into five groups (n=8): control, mild compression demyelination, severe compression demyelination, mild compression remyelination, severe compression remyelination. The fine structures of the tissues obtained were evaluated using electron microscopy. RESULTS: We found a significant difference in the severity of degeneration when comparing group 1 with group 5 (p < 0.001); there was no degeneration in group 1 rats and severe degeneration in all of the group 5 rats. Oligodendrocytes were found in all rats in group 1 and none of the rats in no group 2. The nuclei were preserved in the group 1 rats but damaged in all of the group 5 rats. There were no lymphocytes or erythrocytes in group 1 and all positives in group 5. CONCLUSION: This technique, which induced degeneration without causing damage to the optic nerve with toxic or chemical agents, revealed Wallerian degeneration similar to tumoral compression. After compression relief, the optic nerve remyelination process can be better understood, particularly for sellar lesions. In our opinion, this model may guide future experiments to identify protocols to induce and accelerate remyelination.

Portable MRI to assess optic chiasm decompression after endoscopic endonasal resection of sellar and suprasellar lesions.

OBJECTIVE: Low-field portable MRI (pMRI) is a recent technological advancement with potential for broad applications. Compared with conventional MRI, pMRI is less resource-intensive with regard to operational costs and scan time. The application of pMRI in neurosurgical oncology has not been previously described. The goal of this study was to demonstrate the efficacy of pMRI in assessing optic nerve decompression after endoscopic endonasal surgery for sellar and suprasellar pathologies. METHODS: Patients who underwent endoscopic endonasal surgery for sellar and suprasellar lesions at a single institution and for whom pMRI and routine MRI were performed postoperatively were retrospectively reviewed to compare the two imaging systems. To assess the relative resolution of pMRI compared with MRI, the distance from the optic chiasm to the top of the third ventricle was measured, and the measurements were compared between paired equivalent slices on T2-weighted coronal images. The inter- and intrarater correlations were analyzed. RESULTS: Twelve patients were included in this study (10 with pituitary adenomas and 2 with craniopharyngiomas) with varying degrees of optic chiasm compression on preoperative imaging. Measurements were averaged across raters before calculating agreement between pMRI and MRI, which demonstrated significant interrater reliability (intraclass correlation coefficient [ICC] = 0.78, p < 0.01). Agreement between raters within the pMRI measurements was also significantly reliable (ICC = 0.93, p < 0.01). Finally, a linear mixed-effects model was specified to demonstrate that MRI measurement could be predicted using the pMRI measurement with the patient and rater set as random effects (pMRI ß coefficient = 0.80, p < 0.01). CONCLUSIONS: The results of this study suggest that resolution of pMRI is comparable to that of conventional MRI in assessing the optic chiasm position in relation to the third ventricle. Portable MRI sufficiently demonstrates decompression of the optic chiasm after endoscopic endonasal surgery. It can be an alternative strategy in cases in which cost, scan-time considerations, or lack of intraoperative MRI availability may preclude the ability to assess adequate optic nerve decompression after endoscopic endonasal surgery for sellar and suprasellar lesions.

[Opportunities and challenges in the diagnosis and treatment of optic chiasm lesions: a clinical and research perspective].

The optic chiasm is a critical component of the visual pathway, and lesions in the pituitary and sellar regions can cause irreversible damage to a patient's visual function, resulting in a significant decrease in their quality of life. As a result, neuro-ophthalmology evaluation is a crucial part of the multidisciplinary treatment of pituitary diseases. However, due to the significant variation in the anatomical structure of the optic chiasm and the sellar region, as well as the complexity of the injury mechanism, chiasm injury can result in diverse manifestations and severity levels, which can make it difficult to correlate with anatomical parameters. In recent years, research has increasingly focused on the early recognition of optic chiasm compression, the prediction of visual function after intervention, and the long-term neurodegenerative effects, while optical coherence tomography (OCT), electrophysiological examinations, and functional magnetic resonance imaging are currently the most commonly used methods for evaluating sellar region lesions. However, the role of these methods, represented by OCT, in clinical diagnosis and treatment, still lacks high-level clinical evidence support, and the evaluation and prediction of optic chiasm function remain key areas for further study. In addition to compression lesions, lesions such as inflammation, infiltration, and demyelination in the sellar region, caused by systemic multi-system diseases, can also lead to visual function damage and require recognition in clinical practice.

Decussating axons segregate within the anterior core of the primate optic chiasm.

BACKGROUND: The axons of ganglion cells in the nasal retina decussate at the optic chiasm. It is unclear why tumours cause more injury to crossing nasal fibres, thereby giving rise to temporal visual field loss in each eye. To address this issue, the course of fibres through the optic chiasm was examined following injection of a different fluorescent tracer into each eye of a monkey. METHODS: Under general anaesthesia, cholera toxin subunit B-Alexa Fluor 488 was injected into the right eye and cholera toxin subunit B-Alexa Fluor 594 was injected into the left eye of a single normal adult male rhesus monkey. After a week's survival for anterograde transport, serial coronal sections through the primary optic pathway were examined. RESULTS: A zone within the core of the anterior and mid portions of the optic chiasm was comprised entirely of crossing fibres. This zone of decussation was delineated by segregated, interwoven sheets of green (right eye) and red (left eye) fibres. It expanded steadily to fill more of the optic chiasm as fibres coursed posteriorly towards the optic tracts. Eventually, crossed fibres became completely intermingled with uncrossed fibres, so that ocular separation was lost. CONCLUSIONS: A distinct, central compartment located within the anterior two-thirds of the optic chiasm contains only crossing fibres. Sellar tumours focus their compressive force on this portion of the structure, explaining why they so often produce visual field loss in the temporal fields.

Compression of the optic chiasm is associated with reduced photoentrainment of the central biological clock.

Objective: Pituitary tumours that compress the optic chiasm are associated with long-term alterations in sleep-wake rhythm. This may result from damage to intrinsically photosensitive retinal ganglion cells (ipRGCs) projecting from the retina to the hypothalamic suprachiasmatic nucleus via the optic chiasm to ensure photoentrainment (i.e. synchronisation to the 24-h solar cycle through light). To test this hypothesis, we compared the post-illumination pupil response (PIPR), a direct indicator of ipRGC function, between hypopituitarism patients with and without a history of optic chiasm compression. Design: Observational study, comparing two predefined groups. Methods: We studied 49 patients with adequately substituted hypopituitarism: 25 patients with previous optic chiasm compression causing visual disturbances (CC+ group) and 24 patients without (CC- group). The PIPR was assessed by chromatic pupillometry and expressed as the relative change between baseline and post-blue-light stimulus pupil diameter. Objective and subjective sleep parameters were obtained using polysomnography, actigraphy, and questionnaires. Results: Post-blue-light stimulus pupillary constriction was less sustained in CC+ patients compared with CC- patients, resulting in a significantly smaller extended PIPR (mean difference: 8.1%, 95% CI: 2.2-13.9%, P = 0.008, Cohen's d = 0.78). Sleep-wake timing was consistently later in CC+ patients, without differences in sleep duration, efficiency, or other rest-activity rhythm features. Subjective sleep did not differ between groups. Conclusion: Previous optic chiasm compression due to a pituitary tumour in patients with hypopituitarism is associated with an attenuated PIPR and delayed sleep timing. Together, these data suggest that ipRGC function and consequently photoentrainment of the central biological clock is impaired in patients with a history of optic chiasm compression.

Visual recovery following surgical intervention for pituitary apoplexy correlated with preoperative optical coherence tomography.

Pituitary apoplexy is a rare but potentially fatal endocrinological emergency which can be difficult to diagnose as presenting symptoms vary significantly. Optimal management requires early diagnosis and collaboration between ophthalmology, endocrinology and neurosurgical services. We present a case of pituitary apoplexy in a 52-year-old Caucasian female who was referred by her optometrist to Palmerston North Hospital Eye Clinic with a three-week history of sudden onset moderate bifrontal headaches, two weeks of non-specific peripheral visual changes and dense bitemporal inferior quadrantanopia on formal visual field testing. Ocular motility and slit lamp examination were unremarkable and retinal nerve fibre layer (RNFL) was relatively preserved on optical coherence tomography (OCT). MRI demonstrated a haemorrhagic pituitary macroadenoma elevating and compressing the optic chiasm without cavernous extension. Blood tests revealed mild hypothyroidism, hypocortisolism, hypogonadotropism and hyperprolactinaemia. The patient was commenced on hydrocortisone and levothyroxine replacement and proceeded for urgent transsphenoidal tumour resection at Wellington Regional Hospital. Histology revealed a non-functioning macroadenoma. The patient was asymptomatic and visual field tests had normalised three weeks post-operatively. Six weeks post-operatively, thyroid function and cortisol levels were normal and replacement therapies were ceased.

Diagnostic and Prognostic Utility of Optical Coherence Tomography in Patients With Sellar/Suprasellar Lesions with Chiasm Impingement: A Systematic Review/ Meta-Analyses.

BACKGROUND: In this review, we appraised the current literature on the utility of optical coherence tomography (OCT) as a diagnostic and predictive factor for postoperative visual function outcomes in patients with sellar/suprasellar lesions with chiasmal impingement. METHODS: A systematic search of PubMed, CINAHL, Scopus, and Cochrane Library was conducted following PRISMA guidelines. Included studies described diagnostic or prognostic utility of OCT in patients with sellar/suprasellar lesions with chiasmal impingement. Meta-analysis was represented as mean difference (MD) with 95% confidence intervals. Meta-regression was performed to determine predictive factors of visual outcomes. RESULTS: Forty-eight articles were identified for final pooled analysis, representing a total of 2435 patients with compressive sellar/suprasellar lesions and 952 healthy controls. Mean age was 43.3 (11.4) years, with 1494 (48.8%) male and 1566 (51.2%) female patients. Mean retinal nerve fiber layer (RNFL) was significantly different in the study population compared with healthy controls (75.8 µ [13.2] vs. 91.4 µ [10.8], P < 0.00001). The nasal segment of RNFL had the largest mean difference (MD -9.76 [-12.39, -7.13], P < 0.0001). Visual acuity, visual field mean deviation, and visual field pattern standard deviation all showed significant differences between the study population and healthy controls as well (P < 0.0001). Meta-regressions showed significant predictive capability of preoperative RNFL in determining visual function outcome (P < 0.05). CONCLUSIONS: Our findings provide promising support for the growing evidence that OCT parameters can be utilized as both a diagnostic and prognostic tool for patients with compression of the optic apparatus. There is a need for further studies to gain a better understanding of OCTs and to improve patient outcomes.

Necrosis of the optic nerve and chiasm with safe radiation doses: Report of two rare cases.

INTRODUCTION: Radiation-induced optic neuropathy (RION) is still a devastating complication of brain and skull base radiation that has no effective treatment up until today, thus uttermost caution must be taken in treating patients that brain radiotherapy is needed. We present two cases of RION that happened in seemingly safe radiation doses. CASE DESCRIPTION: A 48-year-old female with a history of pleomorphic pituitary adenoma developed bilateral and painless loss of vision 10 months after radiation to the brain; the total radiation dose was 45 Gy in 25 fractions and no other risk factors of RION were found. Magnetic resonance imaging of the brain depicted bilateral prechiasmatic optic nerve enhancement with involvement of the optic chiasm. Treatment with high doses of corticosteroids was unsuccessful. A 62-year-old female with a history of lung adenocarcinoma and brain metastases presented with a 1-month history of decreased vision in both eyes. He had undergone whole-brain radiotherapy with a total dose of 30 Gy over 10 fractions and concurrent chemotherapy with cisplatin and pemetrexed. Brain magnetic resonance imaging (MRI) with contrast showed bilateral intracranial optic nerve enhancement. CONCLUSIONS: This is the second case report of RION in a patient with a history of brain radiotherapy and concurrent chemotherapy with pemetrexed. History of chiasmal compression, concurrent use of chemotherapeutic agents, and high fraction size (despite the safety of total radiation dose) were possible contributing risk factors to develop RION in our cases. Hence, adjusting the radiation dose according to the presence of these risk factors is recommended.

Cavernous Malformation of the Optic Nerve and Chiasm: Prompt Suspicion and Surgery Matter.

BACKGROUND: Cavernous malformations (CMs) of the optic nerve and chiasm are extremely rare, accounting for less than 1% of all intracranial CMs. Acute, subacute, or progressive visual loss from CM may occur with or without hemorrhage. Prompt surgical excision of the CM offers the best hope to improve or stabilize vision. Given its rarity, optic nerve and chiasm CMs may not be readily suspected. We provide 3 cases of optic nerve and chiasm CM, highlighting key neuroimaging features and the importance of expedited intervention. METHODS: Case records of the neuro-ophthalmology clinics of the Bascom Palmer Eye Institute and the University of Colorado, and literature review of reported cases of optic CM. RESULTS: A 49-year-old woman reported acute progressive painless vision loss in the right eye. MRI showed a suprasellar mass with heterogeneity in signal involving the right prechiasmatic optic nerve. Surgical excision of the CM 5 days after onset of visual loss improved vision from 20/300 to 20/30. A 29-year-old woman with acute painless blurred vision in the right eye had anterior chiasmal junctional visual field defects corresponding to a heterogeneously minimally enhancing mass with blood products enlarging the optic chiasm and proximal right optic nerve. Surgical excision of the CM 8 weeks after onset of visual loss improved vision from 20/40 to 20/15 with improved visual fields. A 33-year-old woman with a history of familial multiple CMs, diagnosed at age 18, reported new-onset severe headache followed by blurred vision. MRI showed a hemorrhagic lesion of the optic chiasm and right optic tract. She was 20/20 in each eye with a reported left superior homonymous hemianopia. No intervention was recommended. Vision of the right eye worsened to 20/400 2 months later. The patient was followed over 13 years, and the MRI and visual function remained unchanged. Literature review yielded 87 optic CM cases occurring across gender and nearly all ages with visual loss and headache as the most common presenting symptoms. Optic chiasm is the most common site of involvement (79%). Nearly 95% of reported CM cases were treated with surgery with 81% with improved vision and 1% with worsened vision. CONCLUSION: MRI features are critical to the diagnosis of optic nerve and chiasm CM and may mimic other lesions. A high index of suspicion by the neuro-ophthalmologist and neuroradiologist leads to early recognition and intervention. Given optic CM displaces and does not infiltrate neural tissue, expedited surgical resection by a neurosurgeon after consideration of other diagnostic possibilities improves visual function in most cases.

Molecular Profile of a Pituitary Rhabdomyosarcoma Arising From a Pituitary Macroadenoma: A Case Report.

Pituitary sarcoma arising in association with pituitary adenoma is an uncommon finding. Most cases of secondary sarcoma have been noted to arise with a median interval of 10.5 years post radiation. In this case report, we describe a 77-year-old man with an incidental discovery of a pituitary macroadenoma on magnetic resonance imaging (MRI) and underwent radiotherapy. Three years after radiation treatment, there was an acute change in clinical symptoms and increase in tumor size and mass effect on the optic chiasm which prompted surgical resection. A pituitary adenoma along with a separate spindle-cell sarcomatous component was identified in histology. Immunohistochemical stain for muscle markers confirmed a development of pituitary rhabdomyosarcoma (RMS). Molecular profiling of the tumor identified mutations in TP53, ATRX, LZTR1, and NF1. Despite its rarity, characterization of pituitary RMS with immunohistochemistry and molecular studies may provide an insight to its pathophysiological relationship with pituitary adenoma.

Discovery of a rare GKAP1-NTRK2 fusion in a pediatric low-grade glioma, leading to targeted treatment with TRK-inhibitor larotrectinib.

Here we report a case of an 11-year-old girl with an inoperable tumor in the optic chiasm/hypothalamus, who experienced several tumor progressions despite three lines of chemotherapy treatment. Routine clinical examination classified the tumor as a BRAF-negative pilocytic astrocytoma. Copy-number variation profiling of fresh frozen tumor material identified two duplications in 9q21.32-33 leading to breakpoints within the GKAP1 and NTRK2 genes. RT-PCR Sanger sequencing revealed a GKAP1-NTRK2 exon 10-16 in-frame fusion, generating a putative fusion protein of 658 amino acids with a retained tyrosine kinase (TK) domain. Functional analysis by transient transfection of HEK293 cells showed the GKAP1-NTRK2 fusion protein to be activated through phosphorylation of the TK domain (Tyr705). Subsequently, downstream mediators of the MAPK- and PI3K-signaling pathways were upregulated in GKAP1-NTRK2 cells compared to NTRK2 wild-type; phosphorylated (p)ERK (3.6-fold), pAKT (1.8- fold), and pS6 ribosomal protein (1.4-fold). Following these findings, the patient was enrolled in a clinical trial and treated with the specific TRK-inhibitor larotrectinib, resulting in the arrest of tumor growth. The patient's condition is currently stable and the quality of life has improved significantly. Our findings highlight the value of comprehensive clinical molecular screening of BRAF-negative pediatric low-grade gliomas, to reveal rare fusions serving as targets for precision therapy.

Inner and outer retinal layer thickness alterations in pediatric and juvenile craniopharyngioma.

We evaluated postoperative retinal thickness in pediatric and juvenile craniopharyngioma (CP) patients with chiasmal compression using optical coherence tomography (OCT) auto-segmentation. We included 18 eyes of 18 pediatric or juvenile patients with CP and 20 healthy controls. Each thickness of the macular retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer, outer plexiform layer, outer nuclear layer, and photoreceptor layer was compared between the CP patients and healthy controls. There was significant thinning in the macular RNFL (estimates [µm], superior, - 10.68; inferior, - 7.24; nasal, - 14.22), all quadrants of GCL (superior, - 16.53; inferior, - 14.37; nasal, - 24.34; temporal, - 9.91) and IPL (superior, - 11.45; inferior, - 9.76; nasal, - 15.25; temporal, - 4.97) in pediatric and juvenile CP patients postoperatively compared to healthy control eyes after adjusting for age and refractive errors. Thickness reduction in the average and nasal quadrant of RNFL, GCL, and IPL was associated with peripapillary RNFL thickness, and reduced nasal quadrant GCL and IPL thicknesses were associated with postoperative visual field defects. In pediatric and juvenile patients with CP, decreased inner retinal layer thickness following chiasmal compression was observed. The changes in retinal structures were closely related to peripapillary RNFL thinning and functional outcomes.

Changes in parafoveal and peripapillary perfusion after decompression surgery in chiasmal compression due to pituitary tumors.

We evaluated changes in parafoveal and peripapillary vessel density in chiasmal compression after decompression surgery using optical coherence tomography angiography (OCT-A). Sixty-two eyes with chiasmal compression for which preoperative and postoperative (4-6 months) OCT, OCT-A, visual field (VF), and comprehensive ophthalmic data were available, and 44 healthy eyes were evaluated. Vessel densities of the superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segment were assessed using OCT-A. The postoperative measurements were compared with preoperative data. Preoperative peripapillary retinal nerve fiber layer, macular ganglion cell-inner plexiform layer thickness, and vessel densities of SRCP and RPC segments in patients' eyes were significantly reduced compared to those of healthy controls (P < 0.0001, P < 0.0001, P = 0.0052, and P = 0.0085, respectively). Vessel densities were significantly decreased in the SRCP (P < 0.0001), DRCP (P = 0.0017), and RPC segments (P < 0.0001) after surgery compared to the preoperative values. Significant associations between the postoperative SRCP and DRCP vessel density changes and preoperative SRCP (r = - 0.3195, P = 0.0114) and DRCP (r = - 0.5165, P < 0.0001) vessel densities were found, respectively. There were also significant associations between postoperative SRCP vessel density changes and VF changes (r = - 0.2586, P = 0.0424). These findings indicate that decreased perfusion around the optic nerve head and on the macula associated with chiasmal compression could further progress after decompression surgery. Further functional and longer-term clinical studies are needed to elucidate the clinical implications of these findings.

Opto-chiasmatic apoplexy as a compartment syndrome? Anatomical and surgical considerations on two bleeding cavernous malformations.

OBJECTIVE: Opto-chiasmatic (OC) cavernous malformations are sporadic lesions that are often misdiagnosed clinically and radiologically. Presenting symptoms range from incidental findings to the more frequent and dramatic "chiasmal apoplexy." The present study aims to evaluate the potential role of arachnoidal membranes of the basal cisterns in the onset of OC apoplexy. A possible mechanism resembling a compartment syndrome is discussed through the description of two cases of bleeding cavernomas. METHODS: We describe clinical, radiological, intraoperative findings in two cases of young patients presenting with OC apoplexy from bleeding cavernoma. The first was a 38-year-old man diagnosed with optic neuritis at the first episode of visual acuity deterioration. The second patient was a 22 -year-old woman who suffered two OC apoplexy episodes from a recurrence, which also presented with bleeding. RESULTS: Both patients were operated on via pterional craniotomy and presented a postoperative improvement of visual symptoms. The second patient experienced deterioration 30 months after surgical resection due to rebleeding from a recurrence and required a second operation. Follow-up revealed a good recovery of visual disturbances; MRI at 6 and 3 years showed in both patients an apparent complete removal of the cavernous malformations. CONCLUSION: The cisternal environment where OC cavernous malformations develop and the paradigm of a compartment syndrome could explain the clinical presentation variability. This very rare subset of cavernomas would benefit from a classification system using ad hoc neuroimaging protocols and consistent indications.

Longitudinal Changes in the Retinal Microstructures of Eyes With Chiasmal Compression.

OBJECTIVE: To test the hypothesis that there was a temporal change in the retinal microstructure after decompression surgery for chiasmal compression, the 1-year longitudinal changes in the inner and outer retinal thickness after decompression surgery were analyzed using spectral-domain optical coherence tomography (SD-OCT) with linear mixed-effects models. METHODS: SD-OCT was obtained from 87 eyes with chiasmal compression and compared to 100 healthy controls. The preoperative and 1-year postoperative longitudinal changes in the retinal layer thickness were measured. The thickness of each of the following retinal layers was analyzed: the macular retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL), the inner plexiform layer (IPL), the inner nuclear layer, the outer plexiform layer, the outer nuclear layer, and the photoreceptor layer. RESULTS: The RNFL, GCL, and IPL showed thinning at a rate of 1.068 µm/y (95% confidence interval [CI], 0.523, 1.613), 1.189 µm/y (95% CI 0.452, 1.925), and 1.177 µm/y (95% CI 0.645, 1.709), respectively, after decompression surgery. The preoperative thickness of the intraretinal layer was associated with postoperative visual field recovery (RNFL, odds ratio [OR] 1.221, 95% CI 1.058, 1.410; GCL, OR 1.133, 95% CI 1.024, 1.254; and IPL, OR 1.174, 95% CI 1.002, 1.376). CONCLUSIONS: The changes in retinal microstructure persisted and progressed in eyes with chiasmal compression after decompression surgery. The findings provide insight into the biological and anatomical sequelae following chiasmal compression. The preoperative thickness of the inner retinal layers was associated with postoperative visual field recovery.

Neurofibromatosis Type 1-Associated Optic Pathway Glioma in Children: A Follow-Up of 10 Years or More.

PURPOSE: This study reports on neurofibromatosis type 1 (NF1)-associated optic pathway gliomas (OPGs) and a follow-up period of at least 10 years in a cohort of children. OPGs are a common manifestation of NF1 and can cause significant visual morbidity. Long-term follow-up in children with NF1-associated OPGs has not been reported previously. DESIGN: Retrospective observational case series. METHODS: This study included children with a documented follow-up of at least 10 years. Three final outcomes were evaluated: visual acuity (VA) per eye (i.e., in the more severely affected eye), VA per patient (i.e., VA when both eyes were open), and the presence of optic nerve head pallor. RESULTS: A total of 45 children were included, followed for a mean of 14 years (range, 10-21 years). At the end of follow-up, abnormal VA (considered moderate to severe impairment) in the more severely affected eye was present in 36% of the patients and in both eyes in 11%. Optic nerve head pallor of 1 or both nerves was present in 62%. In multivariate analysis, only initial VA and optic nerve head appearance at presentation were found to predict the final outcomes. All patients, except for 1, were asymptomatic at presentation and had normal VA and nerves that appeared normal, preserved their good vision in both eyes. Only 1 patient, who had normal VA and normal appearing nerves at presentation, had moderate to severe VA loss at long term follow-up. CONCLUSIONS: In this study, children with NF1-associated OPG whose examination signs and symptoms were normal had a normal initial examination and excellent long-term visual and anatomical outcomes. VA and the appearance of the optic nerve head at presentation predict long-term outcome.

Ophthalmic Manifestations of Rathke's Cleft Cyst and Its Association to Radiological Characteristics.

PURPOSE: To evaluate the ophthalmic features of Rathke's cleft cyst (RCC) and its association with radiological characteristics. METHODS: In this retrospective single-center study, patients who showed typical findings suggestive of RCC on magnetic resonance imaging (MRI) and underwent relevant ophthalmic examination were recruited retrospectively. Patients were stratified into two groups according to the presence or absence of ophthalmic symptoms related to RCC. We reviewed patients' demographic information, initial symptoms, endocrinological status, ophthalmic features, and characteristics of MRI. Height, size and location of RCC, as well as the optic chiasm displacement assessed from MRI. RESULTS: Thirty-three patients (20 women and 13 men) were included in this study from among 335 patients with RCC on MRI. Fifteen patients had ophthalmic manifestation related to the cyst (Ophthalmic group), whereas 18 patients were not (Non-ophthalmic group). Headache was the most common initial symptom (15 patients, 45.5%), followed by visual disturbance (7, 21.2%), diplopia (1, 3.0%), retro-orbital pain (1, 3.0%), galactorrhea (1, 3.0%), and peripheral extremity discomfort (1, 3.0%). In seven asymptomatic patients (21.2%), the lesion was an incidental finding during a regular medical examination. Ophthalmic manifestation included visual field defect (14 patients, 93.3%) and diplopia (1 patient, 6.7%). The height, volume, and the coronal and sagittal displacements were larger in the ophthalmic group (P < .001, all). Eleven patients who manifested ophthalmic symptoms underwent excision surgeries and nine of them (81.8%) experienced visual function improvement. CONCLUSION: Appropriate ophthalmic examinations are warranted in patients with RCC, and treatment should be actively considered in patients with ophthalmic manifestations.