Orbital supratrochlear fistula secondary to anaesthetic block in cataract surgery. / Fístula orbitaria supratroclear secundaria a la realización de un bloqueo para anestesia en una cirugía de catarata.

A case is described of a woman with history of right peribulbar nerve block prior to cataract surgery that, within a few days, presented with a trochlear intraorbital arteriovenous fistula. This was resolved without sequelae after three months by performing intermittent homolateral carotid massages. This is the first case of supratrochlear intraorbital arteriovenous fistula. There are only 8 cases reported of traumatic intraorbital arteriovenous fistula, and only one was with post-peribulbar anaesthesia.

Development of a Novel Thyroid Function Fluctuated Animal Model for Thyroid-Associated Ophthalmopathy.

BACKGROUND: The establishment of a suitable and stable animal model is critical for research on thyroid-associated ophthalmopathy (TAO). In clinical practice, we found that patients treated with I-131 often exhibit TAO; therefore, we aimed to establish a novel thyroid function fluctuated animal model of TAO by simulating the clinical treatment process. METHODS: We treated SD rats with I-131 to damage the thyroid and then used sodium levothyroxine (L-T4) to supplement the thyroid hormone (TH) levels every seven days, leading to a fluctuating level of thyroid hormones that simulated the status of clinical TAO patients. Rats administered normal saline were considered as a control. The weight, intraocular pressure, and serum T3, T4, TSH and TRAb levels of the rats were measured, and the pathological changes were analyzed by H&E staining and transmission electron microscopy (TEM). RESULTS: The experimental rats (TAO group) exhibited significantly reduced weight and elevated intraocular pressure compared with the control rats. Meanwhile, the serum levels of T3 and T4 were up-regulated in the TAO group, but the TSH level decreased during the 10-week study. Moreover, increased numbers of blood vessels and inflammatory cell infiltrations were observed in the orbital tissues of the TAO rats, while no abnormal changes occurred in the control rats. The orbital myofibrils in the TAO rats appeared fractured and dissolved, with twisted structures. Mitochondrial swelling and vacuoles within the endoplasmic reticulum, swelling nerve fibers, shedding nerve myelin, and macrophages were found in the TAO group. CONCLUSION: Rats treated with I-131 and sodium levothyroxine exhibited characteristics similar to those of TAO patients in the clinic, providing an effective and simple method for the establishment of a stable animal model for research on the pathogenesis and treatment of TAO.

Effects of the time of antihypertensive drugs administration on the stage of primary open-angle glaucoma in patients with arterial hypertension.

Many patients with glaucoma suffer from arterial hypertension (AH). It has been proved that both AH and low blood pressure (BP) at night are important vascular risk factors for primary open-angle glaucoma (POAG). The aims of this study were to assess the severity of pathological changes within the optic nerve and characteristics of blood flow in selected arteries of the eyeball and orbit in patients with POAG and controlled hypertension, in relation to the time of hypotensive drugs administration. Eighty-eight patients with POAG and treated, controlled hypertension were examined. The patients were divided into two subgroups, consisting of group A (n = 43), in whom hypotensive drugs were dosed only in the morning and group B (n = 45), in whom hypotensive drugs were also taken in the evening. In patients who were taking hypotensive drugs also in the evening (group B), there was a statistically significant lower mean perfusion pressure at night, a greater visual field loss and reduced amplitude of evoked potentials. Our analysis showed significantly worse changes in the parameters relating to the optic nerve in patients taking hypertensive medicines in the evening and also significantly lower perfusion pressures at night.

[Study on pharmacokinetics of ferulic acid loaded liposome-in-chitosan-microspheres in rats].

In this paper, the pharmacokinetics of ferulic acid loaded liposome-in-chitosan-microspheres was investigated. Eighteen Sprague-Dawley rats were divided into 3 groups randomly. Each group was administered orally of ferulic acid, ferulic acid loaded chitosan microspheres and ferulic acid loaded liposome-in-chitosan-microspheres, respectively. Then blood samples were obtained from fossa orbitalis at different time points. The concentration of ferulic acid in blood was analyzed by a HPLC method using coumarin as internal standard. The data were analyzed by DAS program. The t(max), MRT and t(1/2beta) of liposome-in-chitosan-microspheres were 2.500, 7.487 and 7.818 h, respectively, which were much longer than crude drug and chitosan microspheres. This results demonstrated that liposome-in-chitosan-microspheres had better sus-tained-releasing property. The AUC of liposome-in-chitosan-microspheres was 6.08 times higher than crude drug and 1.21 times higher than chitosan microspheres, which verified that liposome-in-chitosan-microspheres could enhance oral absorption.

Amaurosis, ophthalmoplegia, ptosis, mydriasis and periorbital blanching following inferior alveolar nerve anaesthesia.

BACKGROUND: Ophthalmic complications following inferior alveolar nerve anaesthesia are rare. They include transient blindness (amaurosis), ophthalmoplegia, ptosis, mydriasis and diplopia. These events may occur following the intravascular administration of anaesthetic solution and are distressing to both patient and operator alike. CASE REPORT: We report the unusual case of a young patient who experienced amaurosis, total ophthalmoplegia, complete upper eyelid ptosis, mydriasis and periorbital blanching following inferior alveolar nerve anaesthesia. Similar but less profound signs were observed in the same patient on a subsequent occasion. This was following general anaesthesia, during which she had received local anaesthetic prior to mandibular wisdom tooth removal. CONCLUSIONS: Ophthalmic complications following inferior alveolar nerve anaesthesia are rare but distressing events. In particular, amaurosis is an extremely rare event and usually heralds a more sinister pathology such as stroke. Clinicians should be aware of these complications to minimise anxiety and reassure their patients appropriately.

[Effect of infrared low-intensity laser therapy on orbital blood circulation in children with progressive short sightedness].

This work was designed to study effect of low-intensity infrared laser radiation (LIIRR) on orbital circulation in children with progressive progressive short-handedness. Parameters of the blood flow in the orbital artery, central retinal artery, and posterior ciliary artery were evaluated in a total of 88 patients at the age from 6 to 14 years. The study group (group 1) comprised 66 children with moderately severe progressive myopia (112 eyes), the control one (group 2) included 22 patients without visual disturbances (44 eyes). Patients of group 1 received physiotherapy for the treatment of significantly deteriorated hemodynamics in the orbital region. Indirect action of LIIRR on the orbital region promoted stabilization of short-handedness in 78.8% of the treated patients. It is concluded that the method described in this paper is clinically efficient and may be recommended for the prevention of progressive myopia in children.

Fluoroscopic intralesional injection with pingyangmycin lipiodol emulsion for the treatment of orbital venous malformations.

OBJECTIVE: The objective of our study was to evaluate the efficacy and safety of percutaneous intralesional injection under fluoroscopy with pingyangmycin Lipiodol emulsion (PLE) for the treatment of orbital venous malformations. MATERIALS AND METHOD: . This study is a retrospective analysis of 19 consecutive patients with distensible orbital venous malformations. Of the 19 patients, two had diffuse lesions. These patients presented with proptosis (n = 19), pain and orbital swelling (n = 11), reduction in visual acuity (n = 4), diplopia (n = 2), disk swelling (n = 5), and motility disturbance (n = 3). RESULTS: All 19 patients underwent technically successful percutaneous intralesional PLE injection under fluoroscopy. Complete resolution of proptosis, swelling, and pain was achieved in 17 patients 3-9 months after the procedure. In the other two patients with diffuse lesions, light proptosis was still present after the first procedure. A second procedure was performed in these two patients, and the symptom disappeared 3 months later. All four patients with reduced visual acuity recovered their vision, and diplopia in two patients disappeared. Examinations of the fundus revealed normal findings in the five patients with preprocedural disk swelling. None of the patients presented with a motility disturbance after the procedure. Local swelling in the eyelid and epiphora were present for 1 month in one patient and disappeared after treatment. No other complications, including acute orbital compartment syndrome, were observed during follow-up periods. The mean follow-up was 23 months. CONCLUSION: PLE sclerotherapy under fluoroscopic guidance is safe and effective for the treatment of orbital venous malformations and can be used as one of the treatment alternatives.

Lidocaine+clonidine for maxillary infiltration anaesthesia: parameters of anaesthesia and vascular effects.

The local anaesthetic and haemodynamic parameters achieved by lidocaine with clonidine or epinephrine, administered for maxillary infiltration anaesthesia, were studied in 40 patients (American Society of Anesthesiologists, physical status 1) who underwent upper third molar surgery. All patients received 2 ml of 2% lidocaine with clonidine (15 microg/ml; n=20) or epinephrine (12.5 microg/ml; n=20) in a randomized, double-blind fashion. Vascular effects were evaluated on the isolated human infraorbital arteries. The parameters of maxillary infiltration anaesthsia produced by a combination of lidocaine+clonidine were similar to those obtained with lidocaine+epinephrine. In both groups, haemodynamic parameters exhibited similar variations, with the exception of a significant reduction in heart rate and systolic blood pressure in the lidocaine+clonidine group and significant increase in heart rate in the lidocaine+epinephrine group, 10 min after surgery. Clonidine (10(-7), 10(-6) and 10(-5)M) produced an endothelium-independent vasocontractile effect on the isolated human infraorbital arteries. The results of this study indicate for the first time in dental anaesthesia that the lidocaine+clonidine combination could be a useful and safe alternative to lidocaine+epinephrine for intraoral infiltration anaesthesia.

A case report of Wyburn-Mason syndrome and review of the literature.

INTRODUCTION: Wyburn-Mason syndrome is a distinct congenital neurocutaneous entity comprised of ipsilateral arteriovenous malformations (AVMs) of the midbrain, vascular abnormalities affecting the visual pathway, and facial nevi. METHODS: We report a case and review of the literature of all other reported cases of Wyburn-Mason syndrome (n = 26) in the English literature since 1973. RESULTS: In this review, we report on a 4(1/2)-year-old boy with Wyburn-Mason syndrome who presented with left retinal and orbital AVMs and a ruptured thalamic AVM. The patient did not respond to light in the left eye and demonstrated a left afferent pupillary defect. He did not have any cutaneous lesions. We also characterize other reported cases of Wyburn-Mason syndrome. CONCLUSION: The presentation of patients with Wyburn-Mason syndrome can vary greatly according to the site and the extent of vascular lesions. Intracranial AVMs occasionally hemorrhage with significant morbidity. Treatment is controversial, and patients are typically managed conservatively by observation.

Non-hypothalamic cluster headache: the role of the greater occipital nerve in cluster headache pathogenesis.

Cluster headache is marked by its circadian rhythmicity and the hypothalamus appears to have a significant influence over cluster pathogenesis. However, as not all cluster patients present in the same manner and not all respond to the same combination of medications, there is likely a nonhypothalamic form of cluster headache. A patient is presented who began to develop cluster headaches after receiving bilateral greater occipital nerve (GON) blockade. His headaches fit the IHS criteria for cluster headache but had some irregularities including frequent side shifting of pain, irregular duration and time of onset and the ability of the patient to sit completely still during a headache without any sense of agitation. This article will suggest that some forms of cluster headache are not primarily hypothalamic influenced and that the GON may play a significant role in cluster pathogenesis in some individuals.

Orbital varix rupture during cataract surgery.

We report a case of orbital varix rupture during cataract surgery with retrobulbar anesthesia. No remarkable changes were observed 10 minutes after retrobulbar anesthesia was administered, but a rise in intraocular and intraorbital pressure was noted about 10 minutes after phacoemulsification began. The eyelid could not be closed at the end of surgery because of severe proptosis. Follow-up by magnetic resonance imaging and color Doppler imaging revealed orbital hemorrhage and varix. Based on the time of its appearance, the hemorrhage was thought to be the result of venous congestion caused by anesthetic agent in the muscle cone. Although intermittent exophthalmos is a symptom of orbital varix, silent orbital varix should be considered when selecting the method of anesthesia for ocular surgery.

Branches of the anterior cerebral artery near the anterior communicating artery complex: an anatomic study and surgical perspective.

The anatomy of the branches of the anterior cerebral artery (ACA) near the anterior communicating artery (ACoA) complex were investigated to minimize neurovascular morbidity caused by surgical procedures performed in this region. Thirty-one cadaver brains were perfused with colored silicone, fixed, and studied under the operating microscope. The recurrent artery of Heubner (RAH), orbitofrontal artery (OFA), and frontopolar artery (FPA) were identified as the branches of the ACA arising near the ACoA complex. The OFA and FPA were identified in all hemispheres. Forty-nine (64%) of a total of 77 RAHs arose from the A2 segment. The OFA always arose from the A2 segment, was consistently the smallest branch, and coursed to the gyrus rectus, olfactory tract, and olfactory bulb. The mean distance between the ACoA and the OFA was 5.96 mm. The FPA arose from the A2 segment in 95% of the specimens, and coursed to the medial subfrontal region. The mean distance between the ACoA and the FPA was 14.6 mm. The RAH, OFA, and the FPA are three branches that arise from the ACA near the ACoA complex. These vessels have similar diameters, but can be distinguished by the final destination. Distinguishing these vessels is important since the consequences of injury or occlusion of the FPA and OFA are significantly less than of the RAH.

Hydroxyapatite and calcium phosphate coatings on aluminium oxide orbital implants.

BACKGROUND: Hydroxyapatite and calcium phosphate have been used as bone graft substitutes as they facilitate and promote tissue ingrowth. We carried out a study to examine uncoated and coated aluminium oxide (alumina) spherical orbital implants and assess whether the coatings influence fibrovascular ingrowth. METHODS: The aluminium oxide spheres (three coated with hydroxyapatite, three coated with calcium metaphosphate and three uncoated) were manufactured at the School of Materials Engineering, Yeungnam University, Kyongsan, Kyongbuk, Korea. The implants were examined macroscopically and with scanning electron microscopy and were analysed chemically by means of x-ray powder diffraction and x-ray fluorescence spectrophotometry. Implantation of three hydroxyapatite-coated, three calcium metaphosphate-coated and three uncoated aluminium oxide spheres was done in nine adult male New Zealand albino rabbits. Implant vascularization was evaluated at 4, 8 and 12 weeks by means of histopathological sectioning. RESULTS: All three types of implant had multiple interconnected pores. The coatings increased the size of the trabeculae from 150 microm to 300 microm. As a result, the pores appeared slightly smaller but still ranged in size from 300 microm to 750 microm, compared to 400 microm to 800 microm in the uncoated implants. The coatings also increased the weight of the implants slightly. The implants were all strong mechanically. They were made up primarily of aluminium oxide. The coated implants contained significant amounts of calcium oxide (a contaminant). There was no clinical difference in the socket response between the three groups. Histopathologically, fibrovascularization occurred uniformly throughout each implant at 4, 8 and 12 weeks after implantation. INTERPRETATION: The hydroxyapatite and calcium metaphosphate coatings did not appear to facilitate or inhibit fibrovascular ingrowth at 4, 8 and 12 weeks. Longer-term studies are need to determine whether the coatings play a role in long-term acceptance and retention of the implants.

The triangle of safety: a modified posterior superior alveolar injection technique based on the anatomy of the PSA artery.

The posterior superior alveolar (PSA) injection technique is commonly used to anesthetize soft and hard tissues of the posterior maxilla. As with all injections, complications arise, including hematoma formation secondary to needle-induced vascular trauma. In an attempt to develop a hemorrhage-free PSA injection technique, 361 infratemporal dissections were completed on human cadaver specimens. Three distribution patterns were identified for the external branch of the PSA artery. Regardless of distribution pattern, an anatomical Triangle of Safety was found superior to the maxillary second molar that was free of neurovascular tissues in more than 99% of individuals. Injection into this area appears to meet anesthetic needs while reducing the risk of hematoma formation. The combination of this anatomical triangle with newer anesthetic agents and computerized delivery systems holds promise for continued improvement of the PSA injection technique.

The bioceramic orbital implant: a new generation of porous implants.

PURPOSE: The authors describe a new generation of porous orbital implant made of aluminum oxide (Al2O3) and compare it with the hydroxyapatite orbital implants (Bio-Eye and FCI hydroxyapatite). METHODS: The authors examined the new implant macroscopically, with chemical analysis and microscopically with scanning electron microscopy. Animal implantation studies were performed using six adult male New Zealand albino rabbits. Implant vascularization was evaluated by means of magnetic resonance imaging and histopathologic sectioning. RESULTS: The Bioceramic orbital implant was found to have very uniform pore structure with an average pore size of 500 microm. The implant was 99.9% aluminum oxide on x-ray diffraction. Magnetic resonance imaging in vivo vascularization studies demonstrated enhancement of the implant to its center by 4 weeks after implantation in the rabbit. Histopathologically, fibrovascularization occurred uniformly throughout the implant and was noted by 4 weeks. CONCLUSIONS: The Bioceramic orbital implant represents a new porous orbital implant that has a very regular and extensive interconnected pore system, is as biocompatible as hydroxyapatite, is easy to manufacture, structurally strong, and free of contaminants. It is manufactured with no disruption to marine life ecosystems as may occur in the harvesting of coral for other orbital implants. It is less expensive than currently available hydroxyapatite implants and was approved by the U.S. Food and Drug Administration in April 2000.

Relationship between the effect of carbon dioxide inhalation or nilvadipine on orbital blood flow in normal-tension glaucoma.

PURPOSE: To investigate the relationship between the effect of carbon dioxide (CO2) inhalation or oral nilvadipine, a calcium-channel blocker, on orbital blood flow in patients with normal-tension glaucoma, as determined by color Doppler imaging. PATIENTS AND METHODS: Sixteen patients with normal-tension glaucoma (mean age, 55.6+/-9.8 years; male:female ratio, 3:13) underwent color Doppler imaging to measure the resistance index, and peak systolic and end-diastolic blood flow velocities of the ophthalmic artery, central retinal artery, and nasal and temporal short posterior ciliary arteries. Measurements were taken before and during CO2 supplementation sufficient to increase the end-tidal CO2 partial pressure by 10%. The color Doppler imaging measurements were repeated after 2 to 4 weeks of treatment with 2 mg oral nilvadipine, and comparisons were made between the effects of the two treatments. RESULTS: Both CO2 inhalation and nilvadipine treatment significantly reduced the resistance index in the central retinal artery, nasal short posterior ciliary artery, and temporal short posterior ciliary artery. There was a significant correlation between the effects of the two treatments on the difference in the resistance indexes of the ophthalmic artery and central retinal artery, but not on those of the nasal or temporal short posterior ciliary artery. CONCLUSIONS: Both CO2 inhalation and oral nilvadipine significantly reduce the resistance index measured by color Doppler imaging in orbital vessels. The effect of oral nilvadipine might be predicted by CO2 inhalation in patients with normal-tension glaucoma.

The influence of hyperbaric oxygen therapy and irradiation on hydroxyapatite ocular implant exposure and fibrovascular ingrowth in New Zealand white rabbits.

PURPOSE: Lack of adequate fibrovascular ingrowth has been implicated as a cause of exposure of hydroxyapatite (HA) implants in anophthalmic sockets. We investigated the vasculopathic effects of external beam irradiation, and the fibrovascular-enhancement effects of hyperbaric oxygen (HBO), on HA implant exposure and fibrovascular ingrowth in a rabbit model. METHODS: Eighteen rabbits underwent enucleation with implantation of a 12-mm HA sphere. Six rabbits received 20 Gy of external beam orbital irradiation prior to enucleation. Three irradiated and 6 nonirradiated rabbits received postoperative HBO. Three weeks postoperatively, all rabbits were evaluated clinically for evidence of implant exposure. Implants were then removed, and histopathologic analysis of fibrovascular ingrowth was performed. RESULTS: The amount of vascularization as measured by the depth of ingrowth was greater for nonirradiated (89% ingrowth) than for irradiated (71% ingrowth) animals. HA implant exposure occurred in 1 of 12 (8%) of the nonirradiated, and 4 of 6 (67%) of the irradiated rabbit orbits. HBO did not protect irradiated rabbits from exposure, but did enhance fibrovascular ingrowth in nonirradiated rabbits (100% ingrowth vs. 77% ingrowth). CONCLUSION: Impaired orbital vascularization from prior irradiation appears to retard fibrovascular ingrowth into HA implants, and is associated with an increased incidence of exposure. While HBO did not diminish the likelihood of exposure in irradiated sockets, HA fibrovascular ingrowth in normal orbits appeared to increase with HBO. This may have beneficial clinical application in cases of exposure in nonirradiated orbits.

Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma.

BACKGROUND: Because calcium channel blockers reduce vascular resistance, they may have a clinical application in the treatment of normal-tension glaucoma (NTG). This study investigates changes in both the optic disc blood flow and the hemodynamics of retrobulbar vessels in NTG patients after the systemic administration of a calcium channel blocker. METHODS: Twelve eyes of 12 NTG patients (mean age 57.6 +/- 15.3 years) were examined before and after a 4-week treatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 x 10 pixel window placed on the temporal rim region of the optic disc perfusion map. By ultrasound color Doppler imaging (CDI), we measured the peak systolic velocity (PSV) and the end diastolic velocity (EDV) of the ophthalmic artery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. RESULTS: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05). Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA (P < 0.05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. CONCLUSIONS: Oral nilvadipine appears to reduce orbital vascular resistance, which consequently increases the optic disc blood flow.