Post-decompression optic neuropathy

Blindness resulting from a decompressive craniotomy is uncommon. Five patients with intracranial tumors and papilledema who developed a bilateral optic neuropathy during an apparently uncomplicated craniotomy are presented. Symptoms of visual field loss were minimal preoperatively in four. Visual recovery in general was poor. The nerve fiber bundle pattern of visual field loss in these cases implicates the optic disc as the site of damage in this disorder. It is postulated that hypoperfusion to the prelaminar portion of the optic nerve is the underlying cause.     

Paraneoplastic retinopathy/ optic neuropathy

Opinion statement Paraneoplastic retinopathy and paraneoplastic optic neuropathy comprise a heterogeneous group of ocular syndromes associated with various clinical symptoms and multiple circulating antiretinal antibodies. Current evidence supports an underlying autoimmune mediated process, which is the rationale for the provision of immuno-suppressive therapy in addition to antitumor treatment. There are no controlled clinical trials that address the treatment of paraneoplastic retinopathy and/or optic neuropathy. Management decisions must be based on a relatively small number of case reports. There have been no reports of spontaneous visual improvement in these disorders. Therefore, any improvement after treatment is attributable to the therapeutic intervention. With the exception of the paraneoplastic optic neuropathy patient group, most patients show little or no response to immunosuppressive therapy, and only a small percentage of patients have dramatic improvement. However, modest improvements in visual function can improve patient quality of life and functional independence. Prompt diagnosis and initiation of therapy before significant visual loss is seen seems to be a critical factor in treatment success. An increase in serial autoantibody titers may serve as a marker of disease activity and allow initiation of therapeutic interventions before symptomatic visual decline.     

Endoscopic decompression of the optic canal for traumatic optic neuropathy

Purpose: Traumatic optic neuropathy (TON) is a serious complication of head trauma with the incidence rate of 0.5%e5%. The aim of this study was to investigate the therapeutic efficacy of endoscopic decompression of the optic canal for optic nerve injuries. Methods: In this study, 11 patients treated in our hospital from January 2009 to January 2015 with the visual loss resulting from TON were retrospectively reviewed for preoperative vision, visual evoked potential (VEP) scan, surgical approach, postoperative visual acuity, complications, and follow-up results. Results: All these patients received endoscopic decompression of the optic canal. At the 3-month followup, the visual acuity improvement rate of the 11 patients was 45.5%. The vision acuity of 2 cases improved from hand movement to 0.08 and 0.3 after operation. Another patient''s vision acuity returned to 0.05 compared to light sensation preoperatively. Two cases had finger counting before surgery but they had a vision acuity of 0.4 and light sensation respectively after surgery. However, the other 6 cases'' vision did not improve after surgery. Conclusion: Endoscopic decompression of the optic canal is an effective way to cure TON. VEP could be used as an important reference for preoperative and prognosis evaluation. Operative time after trauma is only a relative condition that may affect the therapeutic effect of optic canal decompression. Poor results of this procedure may be related to the severity of the optic nerve injury.     

Ischemic optic neuropathy following spine surgery

Perioperative visual loss (POVL) is a devastating injury that has been reported infrequently after nonocular surgery. The most common cause of POVL is ischemic optic neuropathy (ION). Increasing numbers of cases of ION are being reported after spine surgery, but the etiology of postoperative ION remains poorly understood. After a MEDLINE search of the literature, we reviewed published case reports of ION, specifically those reported after spine surgery performed with the patient in the prone position. Most of the cases involved posterior ION (PION, n = 17), and the remainder anterior (AION, n = 5). Most patients had no or few preoperative vascular disease risk factors. All except one PION and 2 of 5 AION cases reported symptom onset within the first 24 hours after surgery. Visual loss was frequently bilateral (40% of AION, 47% of PION cases). Mean operative time exceeded 450 minutes. The lowest average intraoperative mean arterial blood pressure was 64 mm Hg and the mean lowest intraoperative hematocrit was 27%. The average blood loss was 1.7 L for AION and 5 L for PION patients. PION patients received an average of 8 L of crystalloid solution and 2.2 L of colloid intraoperatively. This compilation of case reports suggests that a combination of prolonged surgery in the prone position, decreased ocular perfusion pressure, blood loss and anemia/hemodilution, and infusion of large quantities of intravenous fluids are some of the potential factors involved in the etiology of postoperative ION. However, levels of blood pressure and anemia intraoperatively were frequently at levels considered acceptable in anesthesia practice. The etiology of postoperative ION remains incompletely understood. Potential strategies to avoid this complication are discussed.     

Ischaemic optic neuropathy after spinal fusion

Purpose

We report a case of ischaemic optic neuropathy which occurred after prolonged spine surgery in the prone position in an obese, diabetic patient.

Clinical features

The patient was a 44-yr-old, 123 kg, 183 cm man for decompressive laminectomy and instrumented fusion of the lumbar spine. Anaesthesia was induced with thiopentone, fentanyl and succinylcholine and maintained with nitrous oxide, oxygen, isoflurane and a fentanyl infusion. He was positioned prone on the Relton-Hall frame and had an uneventful intraoperative course. Estimated blood loss was 3,000 ml. He was taken to the surgical intensive care unit (SICU) and the trachea was extubated 3.5 hr later. He had no pulmonary or haemodynamic problems and went to a regular nursing floor in the morning. He was discharged home on postoperative day #5. He telephoned his surgeon on postoperative day #7 to say that his vision had been blurry since surgery. His visual acuity was decreased, and on examination, he had a bilateral papillary defect, optic swelling and a splinter haemorrhage in the right eye. Magnetic resonance imaging (MRI) scan of the head and orbits detected no other abnormality. Based on this examination, he was felt to have bilateral ischaemic optic neuropathy and treated conservatively. By postoperative day #47, his visual acuity was greatly improved and near normal. Careful review of possible contributing factors suggests that the cause of the ischaemic optic neuropathy was venous engorgement.

Conclusion

This patient developed ischaemic optic neuropathy from a prolonged interval in the prone position of the Relton-Hall frame, which may be related to venous engorgement.

Objectif

Nous rapportons un cas de neuropathie optique ischémique consécutive à une chirurgie rachidienne prolongée en décubitus ventral chez un obèse diabétique.

Éléments cliniques

Un patient de 44 ans, pesant 123 kg et mesurant 183 cm était opéré pour une laminectomie décompressive avec ostéosynthèse instrumentale de la colonne lombaire. Le thiopental associé à du fentanyl et de la succinylcholine a servi à induire l’anesthésie, qui a été entretenue avec du protoxyde d’azote, de l’oxygène, de l’isoflurane et une perfusion de fentanyl. Il était immobilisé en décubitus ventral sur un cadre de Relton-Hall et l’opération s’est déroulée sans incident. On a estimé la perte sanguine à 3000 ml. Il a été transféré à l’unité des soins intensifs (USI) et extubé 3,5 h plus tard. Il ne présentait aucun problème respiratoire et hémodynamique et on l’a ramené dans son unité de soins le lendemain matin. Il était libéré le cinquième jour. Par téléphone, il avisait son chirurgien le septième jour que sa vision était embrouillée depuis l’intervention. Son acuité visuelle avait diminué et à l’examen, il présentait une lésion papillaire bilatérale, de l’oedème du nerf optique et une hémorragie linéaire de l’oeil droit. L’imagerie par résonance magnétique de la tête et des orbites ne montrait aucune autre anomalie. Cet examen suggérait une neuropathie optique ischémique bilatérale qui fut traitée de façon conservatrice. Le 47^e jour postopératoire, son acuité visuelle s’était améliorée considérablement et était presque redevenue normale. Parmi les facteurs contributoires possibles cette neuropathie ischémique, il faut retenir l’engorgement veineux.

Conclusion

À la suite d’une immobilisation prolongée en décubitus ventral sur un cadre de Relton-Hall, ce patient a présenté une neuropathie optique par ischémie causée vraisemblablement par engorgement veineux.     

显微手术治疗外伤性视神经损伤

目的总结经额入路行显微视神经减压术辅助药物治疗对外伤性视神经损伤的疗效,探讨其治疗原则。方法16例患者经额或额颞入路开颅,显微镜下清除骨折或出血,磨开视神经管,剪开视神经鞘行视神经减压;辅以大剂量皮质类固醇激素、能量合剂和神经营养药物。结果15例患者随访6个月至1年,10例有效,视力不同程度恢复,1例失访。结论经额或额颞入路开颅行显微视神经减压是治疗外伤性视神经损伤有效方法,辅以药物的显微外科治疗是治疗外伤性视神经损伤的一种较理想的治疗方案。     

Ischemic optic neuropathy after lumbar spine surgery

Ischemic optic neuropathy is the most common cause of visual complications after non-ophthalmic surgery. The incidence has varied in different case series, but prone-position spine surgery appears to be involved in most of the reports. We present the case of a 47-year-old woman who developed near total blindness in the left eye following lumbar spine fusion surgery involving the loss of 900 mL of blood. An ophthalmic examination including inspection of the ocular fundus, fluorescein angiography, and visual evoked potentials returned a diagnosis of retrolaminar optic neuropathy. Outcome was poor.     

Simplified limbal incision for extraocular rectus muscle surgery

We describe a limbal incision for extraocular muscle surgery which involves only one incision to the conjunctival-Tenon's layer instead of the three separate incisions required in the standard limbal approach. Based on the 316 extraocular muscle operations in which we have used this one-snip procedure, we conclude that it is simpler and faster than the standard limbal incision, and that it provides good surgical exposure and probably less tissue damage.     

Perioperative risk factors for posterior ischemic optic neuropathy

Background:

Infarction of the optic nerve posterior to the lamina cribrosa, called posterior ischemic optic neuropathy (PION), is a condition that can result in profound bilateral blindness. Cases of PION treated at this institution and those described in the literature were analyzed to identify clinical features that profile those individuals at risk of PION in an attempt to identify major contributing factors that could be addressed prophylactically to enable effective prevention.

Study Design:

Salient clinical features in seven cases of PION diagnosed at the Doheny Eye Institute between 1989 and 1998 are compared with 46 cases of PION reported in the literature.

Results:

In the Doheny series there were six men and one woman aged 12 to 66 years (mean, 47 years). Five patients were status-post spine surgery, one was status-post knee surgery, and one had a bleeding stomach ulcer. Vision loss was simultaneously bilateral in six of seven patients (85.7%) and was apparent immediately after surgery. There were no abnormal retinal or choroidal findings including diabetic retinopathy, in any of the patients. Notable contributing factors were blood loss in all seven patients, ranging from 2,000 to 16,000 mL, with a drop in hematocrit of 9.5% to 19% (mean, 14%), and intraoperative systemic hypotension in all patients. Facial edema was a factor in three of six spine surgery patients (50%). Patients reported in the literature had a mean age of 50 years and were also predominantly men (34 of 46, 74%) who underwent spine surgery (30 of 46, 65.2%).

Conclusions:

Middle-aged men undergoing spine surgery with prolonged intraoperative hypotension and postoperative anemia and facial swelling are at risk of developing PION from hypovolemic hypotension. Avoiding or immediately correcting these contributory factors can reduce the incidence of PION.     

颅脑损伤并发球后视路损伤的手术治疗

作者于近年来收治１５例颅脑损伤并发视力障碍的患者，均经手术治疗。１３例行双额部冠状切开头皮，一侧额部开颅清除眶骨骨折片或出血，矫正额眶骨折错位畸形。有视神经管骨折者，用微钻磨开视神经管，剪开神经鞘进行视神经减压。２例视力障碍伴有眶上裂综合征者行额颞切口，经眶尖外侧壁磨开骨折眶上裂和视神经管，行神经减压。结果：１０例（６５．９％）有效，３例突眼和１例眼球陷入患者均得到矫正。结论：经额颞入路手术减压可对颅脑损伤并发视力障碍取得良好效果。     

先天性眼球震颤眼外肌的超微病理变化

目的：电镜下观察先天性眼球震颤患者眼外肌超微结构，探讨先天性眼球震颤发病过程中的眼外肌超微结构变化。方法：利用电镜观察4例先天性水平型眼球震颤患者内、外直肌的超微结构。结果：①部分肌纤维溶解，胶原纤维增生，形成横向、纵向肌纤维及胶原纤维交错排列的混乱结构；部分肌纤维断裂，断端糖原及线粒体增多。②肌棱内、外囊不同程度的溶解消失，有髓神经纤维脱髓鞘，神经轴突内细胞器成分溶解，梭内肌纤维变性萎缩，神经末梢与梭内肌纤维失去正常的突触结构。结论：先天性情眼球震颤患者眼外肌纤维异常，可影响其收缩牵拉眼球运动的功能；眼外肌肌梭结构异常，可影响肌梭对牵拉力的敏感性，影响眼球本体感受信息的传入，使眼球产生和维持固视功能障碍。     

Removal of an arteriovenous malformation in the optic chiasm. A case of Bonnet-Dechaume-Blanc syndrome without retinal involvement

A rare case of an arteriovenous malformation involving the optic chiasm associated with vascular anomaly in the left maxillary region is presented. The angiogram demonstrated an arteriovenous malformation arising from the anterior circle of Willis (internal carotid, posterior communicating, and proximal anterior cerebral arteries), and located in the region of the optic chiasm and hypothalamus. The case was diagnosed as the Bonnet-Dechaume-Blanc syndrome without intraorbital and retinal arteriovenous malformations. The suprasellar arteriovenous malformation was removed, except for a small portion in the hypothalamus, with satisfactory results.     

Timing of operation for blowout fractures with extraocular muscle entrapment

Abstract

Many authors have advocated early surgical intervention to avoid muscle degeneration in patients with blowout fractures with evidence of extraocular muscle entrapment imaged under computed tomography. However, there is still no golden standard with regard to the target timing of operations for releasing extraocular muscle. Between January 2002 and December 2011, the authors treated eight cases of blowout fracture with extraocular muscle entrapment. Notes from presumed cases of blowout fracture were retrospectively reviewed for information relating to surgical treatment and prognosis. In this series, a patient who was operated on 7 hours after injury showed the quickest recovery from diplopia. In contrast, a patient who was operated on 18 days after injury showed persistent diplopia for 2 years. Nevertheless, in patients who were operated on 3–11 days after injury, there was no obvious correlation between the outcome and the number of days between injury and the operation. It is concluded that, when emergency surgical intervention within several hours is not possible, it should be performed as soon after the injury as possible in order to prevent the increase of predictive fibrosis around the extraocular muscle.     

外伤性视神经病变的疗效分析

目的探讨外伤性视神经病变的治疗方法和效果。方法52例57眼中,44例(48眼)给予药物治疗;9例(9眼)接受经颅视神经减压术,同时给予药物治疗。并将两组疗效对比分析。结果药物治疗48眼,有效16眼,无效32眼,有效率占33.33%;手术治疗9眼,有效4眼,无效5眼,有效率占44.44%。药物治疗和手术治疗比较差异无统计学意义(P=0.795)。结论外伤性视神经病变视力损伤重,治疗效果差,尚无有效的治疗方法。