Postoperative Visual Impairment Research Articles

P18.01.A A MORPHOMETRIC ANALYSIS OF 40 DRY ASIAN SKULLS TO INVESTIGATE ANATOMICAL VARIABILITY IN THE SUPRASELLAR REGION AND ITS IMPLICATIONS IN MENINGIOMA SURGERY

Abstract INTRODUCTION Meningiomas are the most common type of primary brain tumour and when symptomatic, are usually treated by surgical resection. Removing skull-base meningiomas is challenging and subtotal resection remains common, despite utilising the latest surgical METHODS . In the suprasellar region, surgery is particularly high risk and carries a 10-20% rate of postoperative visual impairment. This morphometric analysis of 40 dry skulls furthers our understanding of anatomical variability of 3 structures in the suprasellar region: the limbus sphenoidale (LS), prechiasmatic sulcus (PS) and optic strut (OS). Understanding suprasellar anatomical variability is vital for neurosurgeons operating within the region to reduce complication rates and in achieving gross total resection. METHODS Variants of the LS (A, B and C) are defined according to descriptions used from a previous study. Curved and straight lengths of the LS are measured using metal callipers and string. Between the three variants, statistical analysis is used to compare differences in lengths, and the ratio between their curved and straight length. PS angle, length and width are measured according to previous studies’ definitions. OS position is determined by measuring its distance from the LS and a drawn midline. Skulls are grouped using PS variables and OS position according to adapted classification systems used in previous studies. RESULTS Variants A, B and C of the LS exhibited incidences of 33.33%, 52.82% and 15.39%, respectively. Limbus ratio was significantly different (p<0.05) between variants. Average sulcal angle was 32 ± 13.3°, whilst sulcal type ranked in prevalence: narrow flat sulci (34.21%)> very narrow steep (28.95%)> very narrow flat (21.05%) > narrow steep (15.79%). 32.50% and 18.42% of struts exhibited notable differences in their distances from the midline and from the LS, respectively. CONCLUSION The present study improves our understanding of the prevalence of anatomical variants within the suprasellar region and has implications for meningioma surgery. The type C variant is an overhanging ridge, underneath which meningiomas could be hidden from a surgeon’s view during transcranial procedures. Only two studies have previously documented the type C variant, whose incidence in the present study (15.39%) is within the boundaries of previous research; patients with this variant might require removal of the landmark during surgery to achieve gross total resection. The PS displayed varying degrees of steepness, and skulls were on average steeper than previously documented populations. A considerable proportion of skulls exhibited notable differences in left and right OS position. Establishing PS morphology and OS position preoperatively might be helpful in reducing the risk of visual impairment in future operations through better understanding the course of the optic nerve.

Intraoperative Visual Evoked Potential

In neurosurgery, the intraoperative visual evoked potential(VEP)has recently been used for the management of anterior skull base and parasellar tumors related to the optic pathways to prevent postoperative visual complications. We used light emitting diode photo-stimulation thin pad and stimulator(Unique Medical, Japan). We also recorded the electroretinogram(ERG)simultaneously to exclude technical errors. VEP is defined as an amplitude between the maximum positive wave at 100 ms(P100)and the prior negative wave(N75). In intraoperative VEP monitoring, reproducibility of VEP should be ascertained, particularly in patients with preoperative advanced visual impairment and an intraoperative diminished amplitude. Furthermore, a 50% reduction in the amplitude is critical. In such cases, we should consider suspending or changing surgical manipulation. We have not clearly verified the relationship between the absolute intraoperative VEP value and postoperative visual function. Mild peripheral visual field defects cannot be detected in the present intraoperative VEP system. However, intraoperative VEP with ERG monitoring can serve as a real-time warning to guide surgeons to avoid postoperative visual impairment. We should comprehend the principles, characteristics, disadvantages, and limitations of intraoperative VEP monitoring for reliable and effective utilization.

Endoscopic transnasal surgery in optic pathway gliomas located in the chiasma-hypothalamic region: case series of ten patients in a single-center experience and endoscopic literature review.

Optic pathway gliomas (OPGs) constitute approximately 3-5% of childhood intracranial tumors. In this study, the authors presented their experience of using the endoscopic endonasal approach to treat patients with OPG located in the chiasma-hypothalamic region and aimed to use the infrachiasmatic corridor in the endoscopic endonasal approach as an alternative to the transcranial approach in the surgical necessity of OPGs. We retrospectively analyzed the data of ten patients diagnosed with OPG histopathologically among 3757 cases who underwent endoscopic endonasal surgery between August 1997 and March 2021 at Kocaeli University Faculty of Medicine Pituitary Research Center and Department of Neurosurgery. Mean follow-up period 48.5months. During the postoperative follow-up period, 3 of these 10 patients underwent reoperation due to tumor recurrence. Combined (endoscopic endonasal approach + transcranial approach) approach was applied to 2 patients in the same session. Surgical and clinical outcomes were evaluated in detail. Ten patients with a mean patient age of 20.6 ± 11.4 were included in this study. The most common complaint was visual impairment. After surgery, improvement in visual impairment was observed in five patients. No increase in postoperative visual impairment was observed in any of the patients. Postoperative panhypopituitarism was not observed in any of the patients. STR resection was performed in 5 patients and NTR resection in 5 patients. No additional treatment was required during follow-up in 4 of 5 patients who underwent NTR. A total of 6 patients received postoperative radiotherapy treatment. In gliomas located in the chiasma-hypothalamic region, appropriate patient selection and endoscopic endonasal surgical treatment may contribute to the elimination of symptoms due to the mass effect of the tumor. It may also contribute to keeping the disease under control with targeted adjuvant therapies by clarifying the pathological diagnosis of the lesion.

Tuberculum Sellae Meningioma – Multiple Skullbase Approaches: Their Safety And Efficacy

Background: Tuberculum sellae (T.S.) meningiomas accounts for 5–10% of all intracranial meningiomas. The primary goal of surgery is to improve or at least maintain visual function, but this objective poses a formidable surgical challenge, because of the risk of postoperative visual impairment. The aim of the present study was to evaluate outcome in TSM patients treated microsurgically using multiple skull base approaches such as transcranial approach and extended endonasal transsphenoidal approach. Materials and Methods: This is a retrospective study of 34 patients was aimed to observe the efficacy of the different common approaches by a single neurosurgeon. The approaches were minipterional approach, superciliary keyhole microscopic approach, superciliary keyhole endoscopic assisted approach, bifrontal basal approach and extended endoscopic endonasal approach. All the patients were evaluated preoperatively by visual field analysis and contrast MRI. Postoperative follow-up was done by visual field analysis and by contrast MRI or contrast CT scan of brain. Result: Through transcranial surgery vision improved in 86.20%, static in 10.34% and deteriorated vision in 03.45%. Through transsphenoidal surgery vision improved in 80%, static in 20% and deteriorated in 0%. Through transcranial microscopic approaches (minipterional, minibifrontal basal, superciliary keyhole microscopic) gross total removal was done in 58.82%, near total in 10.34% and partial removal in 03.45%. Through transcranial/superciliary keyhole endoscopic assisted approach, gross total removal was done in 80% and near total in 20%. Through transsphenoidal approach gross total removal was done in 60%, near total in 20% and partial removal in 20%. Conclusion: Now a days endoscopic assisted key hole superciliary mini craniotomy for resection of tuberculum sellae meningioma is commonly used because of less morbidity and good visual outcome and this can be done without microscopic set up. The endonasal route is preferred for removal of T.S. meningioma when they are mostly sellar and directing towards third ventricle. The major limitation of this approach is a narrow surgical corridor. The gross total removal was better achieved with minibifrontal basal and minipterional craniotomy. Bang. J Neurosurgery 2022; 11(2): 80-88

Clinical observation of microsurgical removal of the hemilateral tuberculum sellae meningiomas through contralateral eyebrow arch approach

The current study aimed to investigate the clinical feasibility of microscopic resection of hemilateral tuberculum sellae meningiomas (TSM) via the contralateral eye brow arch approach. The clinical data of 34 patients with TSM who underwent microsurgery from January 2016 to June 2021 in the Neurosurgery Department of Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine and the First Affiliated Hospital of Henan University were collected and reviewed. The postoperative visual acuity improvement rate was 88.5% (23/26), and the total tumor resection rate was 88.2% (30/34); the postoperative visual acuity improvement in patients with total tumor resection was better than that of patients with partial resection [90.9% (20/22) vs 3/4]. Meanwhile, the postoperative visual acuity improvement in patients with the superior optic nerve and laterl-superior optic nerve was better than that of patients with the lateral optic nerve type (12/14, 8/8 vs 3/4). Supraorbital skin numbness occurred in 3 cases after operation, and the symptoms disappeared during follow-up; 2 cases had mild disturbance of hormone level, and urine output of 2 cases increased after operation, which returned to normal level after symptomatic treatment; 1 case had subcutaneous effusion which was absorbed after treatment. There were no complications such as olfactory disturbance and intracranial infection. During follow-up for 3-60 (33±6) months, recurrence occurred in 2 cases and reoperation was performed. For the hemilateral TSM, according to the preoperative evaluation of the origin of the TSM and the side with visual impairment, the contralateral eyebrow approach is selected to fully expose the tumor base below the optic nerve. It is beneficial to fully resect the tumor under direct vision, and the symptoms of postoperative visual impairment are significantly improved, indicating that the current surgical method can be used in the clinical setting.

Individualized surgical treatment of giant tuberculum sellae meningioma: Unilateral subfrontal approach vs. endoscopic transsphenoidal approach.

Giant tuberculum sellae meningiomas (TSMs) are deeply located in the suprasellar region and extensively compressed or encased in the surrounding neurovascular structures, making gross total resection (GTR) without postoperative visual impairment challenging. The authors presented individualized unilateral subfrontal approach and endoscopic transsphenoidal approach (ETSA) in a series of patients and elaborated on their advantages and indications in resecting giant TSMs. A total of 38 patients with giant TSMs operated by a single surgeon between March 2012 and November 2021 were retrospectively reviewed. Patients underwent unilateral subfrontal approach and ETSA according to preoperative imaging characteristics. Tumor characteristics, surgical details, preoperative symptoms, and neurological outcomes of TSMs patients were collected and analyzed. In 31 patients operated with the unilateral subfrontal approach, total resection (Simpson grade I or II) was achieved in 27 patients (87.0%), while 6 patients (85.7%) achieved GTR in 7 patients using ETSA. The postoperative visual improvement was maintained in 22 (81.5%) and 5 patients (83.3%). Recurrence or progression was only observed in 2 (7.4%) patients operated with the unilateral subfrontal approach. There was no mortality in our series. Preoperative imaging and visual function are important for surgical approach selection. Maximum tumor resection and optic nerve protection can be achieved concurrently by taking advantage of these surgical approaches. The cerebral artery protection strategies and individualized surgical techniques provide great utility in improving a patient's quality of life.

Real-world visual outcomes of cataract surgery based on population-based studies: a systematic review

Background/aimsQuantity of cataract surgery has long been an important public health indicator to assess health accessibility, however the quality of care has been less investigated. We aimed to summarise the...

Diagnostic Impact of Monitoring Visual Evoked Potentials to Prevent Visual Complications During Endovascular Treatment for Intracranial Aneurysm.

IntroductionThe present study aimed to determine the incidence of intraprocedural visual-evoked potential (VEP) changes and to identify correlations with intraprocedural ischemic complications during endovascular treatment in patients with intracranial aneurysm related to visual function.MethodsThis study analyzed data from 104 consecutive patients who underwent endovascular coil embolization to treat intracranial aneurysms related to visual function under VEP and transcranial motor evoked potential (MEP) monitoring. We analyzed associations between significant changes in MEP and VEP, defined as a >50% decrease in amplitude, and both intraprocedural complications and postoperative neurological deficits. Factors associated with postoperative neurological deficits were also assessed.ResultsTreated aneurysms were predominantly located in the internal carotid artery (95%). Five (5%) were located in the posterior cerebral artery (PCA). Significant decreases in intraprocedural VEP occurred in four patients (4%), although one of those four patients did not show concomitant MEP decreases during procedures. Immediate salvage procedures avoided postoperative visual disturbances. All VEP decreases were transient and not associated with postoperative visual impairment. One of three cases who underwent intraoperative balloon occlusion test showed tolerance to balloon occlusion of the proximal PCA under VEP assessment; parent artery occlusion was performed without postoperative visual disturbance in that case.ConclusionAlthough significant VEP decreases occurred 4% during neuro-endovascular aneurysm treatment related to visual function, intraprocedural VEP monitoring identifies ischemic changes associated with visual pathways and facilitates prompt initiation of salvage procedures.

The clinical application of intraoperative visual evoked potential in recurrent craniopharyngiomas resected by extended endoscopic endonasal surgery

ObjectiveThe protection of visual function is a major challenge for recurrent craniopharyngioma due to the interface between tumor and surrounding structure (esp. optic nerve) is more unclear. Intraoperative visual evoked potential (VEP) has been integrated into transsphenoidal surgery for pituitary adenomas and primary craniopharyngiomas in the prediction of postoperative visual outcome. In the present study, we firstly analyzed the clinical value of the VEP in the prediction of postoperative visual outcome for recurrent craniopharyngiomas by extended endoscopic endonasal surgery (EEES). MethodsThirty-six patients with recurrent craniopharyngiomas who underwent EEES with intraoperative VEP monitoring were retrospectively reviewed. The association between the changes in the VEP amplitude and postoperative visual outcome was determined. In addition, other potential prognostic factors with regard to postoperative visual outcomes were also included in the analysis. ResultsGross total resection (GTR) was achieved in 32 patients (88.9%). Reproducible and stable VEP was recorded in 72 eyes. We recorded that there were 29 eyes remained stable VEP amplitude intraoperation, 4 (13.8%) of which suffered new visual acuity (VA) and 5 (17.2%) suffered new visual field (VF) defects after surgery. A transient VEP decrease was recorded in 41 eyes, 8 (19.5%) of which suffered from visual deterioration. Of 2 eyes with a permanent VEP decrease, 2 (100%) experienced postoperative visual impairment. Clinical variable analyses revealed a significant correlation between recurrent craniopharyngioma and age, adhesion with optic nerve, postoperative VA, and intraoperative VEP amplitude. Unstable VEP amplitude during operation and tight adhesion were independent risk factors for postoperative VA. Tight adhesion and a larger tumor volume were independent risk factors for postoperative VF defects. ConclusionsEEES provides a unique view for the lesions under and behind the chiasm and achieve higher rates of GTR with improved visual outcomes. Tight adhesion and unstable VEP amplitude were strong predictors of postoperative visual impairment. Recurrent craniopharyngiomas are more likely to adhere to the optic nerve, VEP is more likely to be unstable during operation, and the improvement rate of postoperative visual function is lower than primary craniopharyngiomas. So intraoperative VEP is more necessary for recurrent craniopharyngiomas.

Surgical Outcomes of Endoscopic Endonasal Versus Transcranial Resections of Adult Craniopharyngioma: A Meta-Analysis.

The endoscopic endonasal approach (EEA) has been gaining popularity for resection of adult craniopharyngiomas. However, the safety and effectiveness of the procedure in comparison to the traditional transcranial approach (TCA) remains unestablished as previous reviews are outdated. A literature search without language restriction was conducted in PubMed, Cochrane database, and Web of Science from conception to July 9, 2021. Cohort studies and case series that compared EEA with TCA and assessed postoperative complications, recurrence, and 30-day mortality were included. Articles, where data for adult populations could not be extracted or calculated, were excluded. Article selection and data extraction in a predesigned data extraction form were conducted in duplicate. Pooled participant data were included in a random-effects model. The search yielded 227 articles, from which eight cohort studies containing 11,395 patients were included (EEA: 6,614 patients, TCA: 4,781 patients). Six studies were good quality and two were fair quality according to the Newcastle Ottawa Scale. There were significantly higher rates of cerebrospinal fluid leak (risk ratio [RR]=0.23, 95% confidence interval [CI] 0.17-0.32, p<0.00001, I²=0%) and lower rates of postoperative hypopituitarism (RR=1.40, 95% CI 1.30-1.51, p<0.00001, I²=0%), hydrocephalus (RR=6.95, 95% CI 5.78-8.36, p<0.00001, I²=0%), visual impairment (RR=1.52, 95% CI 1.34-1.73, p<0.00001, I²=0%), and 30-day mortality (RR=5.63, 95% CI 3.87-8.19, p<0.00001, I²=0%) after EEA. Non-significant lower rates of postoperative diabetes insipidus (RR=1.12, 95% CI 0.78-1.61, p=0.53, I²=85%) and recurrence of tumor (RR=2.69, 95% CI 0.35-20.81, p=0.34, I²=47%) were seen after EEA. EEA may be associated with reduced postoperative hypopituitarism, hydrocephalus, visual impairment, and 30-day mortality and higher rates of cerebrospinal fluid leak. These findings do not account for differences in tumor size and extension between the EEA and TCA cohorts. Further research on patients with comparable tumor characteristics is required to fully assess outcomes.

Predictors of early visual outcome after endoscopic trans sphenoidal excision of pituitary adenomas

BACKGROUND: Endoscopic transsphenoidal excision has revolutionized the surgical management of pituitary macroadenoma. There had been several retrospective studies on the factors determining the visual outcome after surgical excision of pituitary adenoma, but very few prospective studies were published in this context. This is a prospective study of the factors predicting visual outcome following endoscopic transsphenoidal excision of pituitary adenoma. Various factors like age, duration of visual symptoms, the volume of the tumour, suprasellar extension, parasellar extension, type of adenoma, pituitary apoplexy, completion of excision, fundoscopic changes, and preoperative visual deficits were studied. METHODS: Single centre prospective observational study done between November 2016 to December 2018. Thirty patients with pituitary macroadenoma who underwent trans nasal endoscopic excision were studied with preoperative and postoperative visual impairment score (VIS) and the visual outcome was categorized as a good outcome if there was more than 5% improvement in VIS and as worse otherwise. Various predictors that may influence the outcome were statistically compared. RESULTS: 83.3% of patients (n=25) showed improvement in their vision at 6months follow-up. Overall visual outcome (considering both parameters visual acuity and visual field together) was dependent on suprasellar extension (P=0.01), completion of excision (P=0.004), and primary optic atrophy (P=0.018). On subgroup analysis recovery in visual acuity was significantly determined by the preoperative tumour volume(P=0.041), suprasellar extension (P=0.006), completion of excision(P=0.003), and primary optic atrophy (P=0.013). The improvement in the field of vision depended on the severity of preoperative field defects (P=0.04) and completion of excision (P=0.01). CONCLUSIONS: The factors predicting the early visual outcome were the suprasellar extension, completion of excision, preoperative field deficits, and primary optic atrophy. This study highlights the importance of early and proper intervention in pituitary adenomas managed surgically to procure the desired result.

The predictive value of intraoperative visual evoked potential for visual outcome after extended endoscopic endonasal surgery for adult craniopharyngioma.

Due to the proximity of craniopharyngioma to the optic apparatus, one of the most common complications after surgery is visual deterioration. Intraoperative visual evoked potential (VEP), as a means of real-time visual function monitoring, has been integrated into transsphenoidal surgery for pituitary adenoma to predict postoperative visual outcome. Compared with pituitary tumor, craniopharyngioma often adheres to optic nerves, with increased risk of postoperative visual impairment. Furthermore, extended endoscopic endonasal surgery (EEES) can provide direct visualization of the surgical plane between the craniopharyngioma and the optic nerves, which contributes to analysis of the mechanism of real-time VEP changes during surgery. Therefore, VEP monitoring applied during EEES for craniopharyngioma may have more clinical value. However, only 9 patients who underwent EEES with VEP monitoring for craniopharyngioma have been sporadically reported to date. In this paper, the authors present the largest series to date analyzing the clinical value of VEP to predict postoperative visual outcome in adult patients with craniopharyngioma. Sixty-five adult patients who underwent EEES with intraoperative VEP monitoring for primary craniopharyngioma were retrospectively reviewed. The association between changes in VEP amplitude and postoperative visual outcome was determined. In addition, other potential prognostic factors with regard to postoperative visual outcomes were included in the analysis. Gross-total resection was achieved in 59 patients (90.8%). Reproducible and stable VEP was recorded in 128 of 130 eyes (98.5%). During surgery, VEP remained stable in 108 eyes, 10 (9.3%) of which had new visual acuity (VA) and/or visual field (VF) defects after surgery. Transient VEP decrease was recorded in 15 eyes, 4 (26.7%) of which had visual deterioration. Of the 5 eyes with permanent VEP decrease, 3 (60%) experienced postoperative visual impairment. Permanent VEP decrease (OR 19.868, p = 0.007) and tight adhesion (OR 6.104, p = 0.040) were independent adverse factors for postoperative VA deterioration. Tight adhesion (OR 7.150, p = 0.002) and larger tumor volume (OR 1.066, p = 0.001) were significant risk factors for postoperative VF defects. Intraoperative VEP monitoring can serve as a real-time warning to guide surgeons to avoid postoperative visual impairment. It effectively predicted VA changes in adult patients with craniopharyngioma after EEES. Tight adhesion and larger tumor volume were also strong predictors of postoperative visual impairment.

뇌하수체 종양 수술에서 수술중신경계감시: 증례보고

Visual evoked potential (VEP) is a useful tool for monitoring the visual pathway during surgery. We report two cases with pituitary adenoma who had intraoperative VEP monitoring during the tumor removal surgery via the transsphenoidal approach. One case had transient delayed VEP latency during the tumor removal. The other case had transient decreased VEP amplitude with recovery to the baseline. Our two cases had no postoperative visual impairment. Intraoperative VEP monitoring could be applied during the surgical treatment of the lesion near the visual pathway such as the pituitary adenoma.

Cystoid macular oedema after descemet membrane endothelial keratoplasty

AimsTo determine the incidence and risk factors of cystoid macular oedema (CMO) following descemet membrane endothelial keratoplasty (DMEK) with or without combined cataract surgery (triple-DMEK).MethodsWe reviewed the records of patients...

Outcome in pituitary apoplexy patients, stratified by delay between symptom appearance and surgery: A single center retrospective analysis

BackgroundThere are surgical and conservative management strategies in pituitary apoplexy patients. The use of both methods may lead to delayed surgery in the treatment of pituitary apoplexy. The aim of this study was to evaluate the surgical indications and outcomes of a series of patients with pituitary apoplexy according to delay between surgery and symptom onset. MethodsA retrospective analysis was performed of 2711 cases with sellar pathologies treated with endoscopic transsphenoidal surgery in a single centre. Inclusion criteria were histopathological confirmation of haemorrhage or necrosis, acute onset and at least one of the following: symptoms of endocrine dysfunction; visual impairment; ophtalmoplegia; headache; or altered consciousness. Patients were divided into three groups based on the number of days from initial symptoms to surgery: early (1–7 day), delayed (8–21 days) and late (>21 day). The indication for and outcome of surgery was reviewed according to symptoms and timing of surgery. ResultsNinety-one patients with pituitary apoplexy underwent surgery. The median time from ictus until surgery was 16 days (1–120 days). Headache was the most common presenting symptom. Visual impairment and ophtalmoplegia were found in 26.4% and 23.1% of patients, respectively. Surgical intervention was successful in treatment of headache in 82 (97,6%) patients. In patients in the early or delayed groups a significant improvement was found between pre- and post-operative headache, ocular palsy, visual impairment, and hormone deficiencies. Patients in the late group also had a significant improvement in headache and visual symptoms after surgery. ConclusionSurgery was sufficient in headache, endocrine, and neuro-ophthalmic outcomes at first 21 days (early and delayed groups). Beyond 21 days (late group), surgery was not effective on recovery of pituitary function.

Incidence and risk factors of postoperative visual function impairment in elderly patients undergoing nonocular surgery: a prospective cohort study

BackgroundElderly patients may present with visual function impairment after surgery, which may increase the incidence of postoperative delirium and falls and decrease their quality of life. The aim of this study was to assess visual function in elderly patients after long-duration nonocular surgery to determine the incidence and risk factors for visual function impairment after surgery. MethodsThis prospective and observational study included patients aged between 60 and 80 years who had been scheduled for elective nonocular surgery expected to last longer than 120 minutes under general anesthesia. Ocular examinations were performed before surgery, on postoperative day 3 and on postoperative day 21 and consisted of a LogMAR-Snellen chart test, a Jager chart test, biomicroscopy, optical tonometry, ocular motility assessment and fundoscopy. Baseline characteristics of all patients as well as intraoperative and postoperative data were collected. ResultsA total of 107 patients were included in the final analysis. Visual function impairment was diagnosed in 21 patients (19.6%) at POD 3. Of those, 7 patients (6.5%) still presented with visual changes at POD 21. On POD 3, compared with that at baseline, visual acuity assessed by the Snellen chart test had decreased in these patients. Significant differences regarding refraction tests and intraocular pressure measures were also found. Multivariable analysis identified diabetes mellitus, duration of surgery, hypotension during anesthesia induction, lower peripheral oxygen saturation at the end of the procedure and body mass index as independent risk factors for postoperative visual impairment. ConclusionIn elderly patients undergoing long-duration nonocular procedures under general anesthesia, the incidence of visual function impairment was considerably high. Most patients recovered to baseline visual function, but clinically significant visual changes may still be present 3 weeks after surgery. Obesity, diabetes mellitus, and the duration of surgical and anesthetic techniques appear to increase the risk of visual impairment after surgery.

Diffusion Tensor Imaging and Neurite Orientation Dispersion and Density Imaging Assessment of Optic Pathway Function in Patients With Anterior Visual Pathway Compression.

In patients with sellar or parasellar tumors, it is crucial to evaluate visual field impairment in the preoperative stage and to predict visual field improvement after the surgery. The purpose of this study was to investigate the associations of diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) parameters in the optic radiations with preoperative and postoperative visual field impairment. This prospective study included 81 participants with sellar or parasellar tumors. Multishell diffusion imaging and a visual field impairment score (VFIS) were acquired before and after the surgery. The multishell diffusion-weighted imaging was acquired to measure the neurite density and neurite orientation dispersion, as well as the diffusivity. DTI parameters were fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity, and radial diffusivity (RD). NODDI provided intracellular volume fraction (Vic), the orientation dispersion index, and isotropic volume fraction (Viso). The associations of DTI and NODDI parameters in the optic radiations with VFIS were investigated, adjusting for age, tumor height, and symptom duration. Among 162 optic radiations, 117 were functionally impaired in the preoperative stage. FA and Vic had significant negative correlations, whereas MD and RD had significant positive correlations with the VFIS (all P < 0.001). In the preoperative stage, lower FA (P = 0.001; odds ratio = 0.750) and Vic (P = 0.003; OR = 0.827) and higher MD (P = 0.007; OR = 1.244) and RD (P < 0.001; OR = 1.361) were significantly associated with the presence of visual field impairment. For the degree of postoperative improvement, preoperative lower Vic (P = 0.034; OR = 0.910) and higher MD (P = 0.037; OR = 1.103) and RD (P = 0.047; OR = 1.090) were significantly associated with more postoperative improvement. DTI and NODDI parameters in the optic radiations were correlated with VFIS and associated with preoperative visual field impairments and postoperative improvement. It may help in predicting visual field improvement after the surgery in patients with sellar or parasellar tumors.

Volumetric Analysis and Clinical Outcome in 54 Patients with Retrobulbar Hematoma

Retrobulbar hematoma (RBH) is a rare but serious vision threatening emergency. We analyze the relationship between hematoma volume, visual impairment and outcome. Fifty-four patients with RBH receiving orbital decompression were retrospectively included. Volumetric analysis of RBH was performed by semi-automatic segmentation based on preoperative CT scans using ITK-SNAP software. Best corrected visual acuity (BCVA) measurements were obtained and correlated in 2 groups (no light perception (NLP), severe visual impairment) with the hematoma volume. NLP was documented preoperatively in 5/28 and postoperatively in 9/43 patients. Preoperative NLP was significantly associated with a larger hematoma volume (P=.03) and higher hematoma/orbital volume ratio (P=.03). Postoperative severe visual impairment showed significant associations with a larger hematoma volume (P=.02) as well as higher hematoma/orbital volume ratio (P=.02). Eyes with severe visual impairment and large hematoma volumes preoperatively are at high risk of permanent vision loss. Hematoma volume calculation might represent an additional prognostic parameter for visual outcome after RBH.

Impact of Anterior Clinoidectomy on Visual Function After Paraclinoid Carotid Artery Aneurysm Surgery: Power-Drill Versus No-Drill Technique

ABSTRACT BACKGROUND Few studies have attempted to make a direct comparison of the risk of visual impairment following extradural anterior clinoidectomy (EAC) with and without the use of a power drill. OBJECTIVE To evaluate postoperative visual outcomes between groups of patients with paraclinoid carotid artery aneurysms (PCAAs) who underwent surgical clipping with and without the use of a power drill during EAC. METHODS Between January 2010 and November 2019, 90 patients, 7 with ruptured and 83 with unruptured PCAAs, underwent clipping surgery at our hospital. The authors retrospectively analyzed postoperative visual complications from the medical records of these patients. RESULTS Among the 85 patients (excluding 3 patients with disturbance of consciousness caused by subarachnoid hemorrhage and 2 patients with preoperative visual disturbance) evaluated, EAC was conducted using a power drill in 64 patients and using a microrongeur in 21 patients. Permanent postoperative visual impairment developed in 14 (21.9%) patients in the drill group: 9 patients had ipsilateral lower nasal quadrant hemianopsia (ILNQH) and 5 patients had ipsilateral visual acuity reduction. Transient ILNQH developed in only 1 patient in the no-drill group. The incidence of permanent postoperative visual impairments was significantly lower in the no-drill group than in the drill group (P = .020). Seventeen (26.6%) patients developed transient oculomotor nerve palsy in the drill group, while no patients developed oculomotor nerve palsy in the no-drill group. CONCLUSION EAC using a microrongeur versus a power drill significantly improved visual outcomes after clipping surgery for PCAAs.

Visual Field Defect Before and After Endovascular Treatment of Occipital Arteriovenous Malformations.

Occipital arteriovenous malformations (AVMs) carry a high risk of postoperative morbidity because of their anatomic relation to the visual cortex and optic radiations. Data regarding endovascular management of these lesions are scant. To report our single-center experience with occipital AVMs, most of which were treated endovascularly, with a special interest for postoperative visual impairment. From a prospective database, we assessed the clinical and radiological data of all patients with an occipital AVM managed between 1997 and 2018. The extension of the nidus to the primary visual cortex was assessed and correlated to the pre- and postintervention visual symptomatology. Modified Rankin Scale and visual fields (VFs) were assessed pre- and post-treatment and at the last follow-up. A total of 83 patients (47 males [56.6%]) with an occipital AVM were included in the study. Mean age at presentation was 33.5±15.0 yr (min-max=7-76). A total of 34 patients (41%) presented with hemorrhage related to the AVM. A total of 57 patients (68.7%) underwent endovascular treatment (EVT) alone, 20 (24.1%) underwent embolization and surgery, 3 (3.6%) underwent embolization and radiosurgery, and 3 (3.6%) were conservatively managed. A complete obliteration of the AVM was achieved in 53 patients (66.3%). A post-treatment worsening of the VF was found in 24 of the treated patients (30%), 3 patients (9%) for ruptured AVMs, and in 21 patients (46%) for unruptured AVMs. Morbidity rate was 3.7% and mortality rate was 2.5%. EVT of occipital AVM carries a non-negligible rate of complications, especially regarding visual functions.