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Concept: Ophthalmic artery

146

There are considerable variations in the anatomy of the human ophthalmic artery (OphA), such as anomalous origins of the OphA and anastomoses between the OphA and the adjacent arteries. These anatomical variations seem to attribute to complex embryology of the OphA. In human embryos and fetuses, primitive dorsal and ventral ophthalmic arteries (PDOphA and PVOphA) form the ocular branches, and the supraorbital division of the stapedial artery forms the orbital branches of the OphA, and then numerous anastomoses between the internal carotid artery (ICA) and the external carotid artery (ECA) systems emerge in connection with the OphA. These developmental processes can produce anatomical variations of the OphA, and we should notice these variations for neurosurgical and neurointerventional procedures.

Concepts: Embryo, Developmental biology, Internal carotid artery, Common carotid artery, External carotid artery, Embryology, Arteries of the head and neck, Ophthalmic artery

140

Embozene® is a new neuroembolizing microsphere used to reduce intraoperative bleeding for head and neck tumours. We report a case of iatrogenic ophthalmic artery occlusion after Embozene® embolization of the external carotid artery (ECA).

Concepts: Head and neck anatomy, Head and neck, Internal carotid artery, Common carotid artery, External carotid artery, Arteries of the head and neck, Ophthalmic artery

28

PURPOSE.: This study aimed to evaluate the changes in retrobulbar blood flow by using color Doppler sonography in patients who had undergone intravitreal ranibizumab injection for neovascular age-related macular degeneration (AMD). METHODS.: The study comprised 37 AMD patients who had undergone intravitreal 0.5 mg ranibizumab injection. The ophthalmic artery, central retinal artery, and short lateral posterior ciliary artery of both eyes of patients were evaluated by color Doppler sonography. Peak systolic velocity, end-diastolic velocity, and resistance index were calculated before injection, and after injection on day 7 and day 30. The pre- and postinjection values were compared using Wilcoxon signed rank test. RESULTS.: In a comparison with the preinjection values of peak systolic velocity, end-diastolic velocity, and resistance index, the postinjection values at both day 7 and day 30 showed no statistically significant difference in ophthalmic artery, lateral posterior ciliary artery, and central retinal artery (p > 0.05). Similarly, for the same parameters, pre- and postinjection values in the uninjected fellow eye showed no statistically significant difference (P > 0.05). CONCLUSIONS.: Intravitreal ranibizumab injection for neovascular AMD does not cause a significant change in the retrobulbar blood flow in either the injected eye or the fellow eye. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound 2013.

Concepts: Statistical significance, Retina, Eye, Medical ultrasonography, Macular degeneration, Arteries of the head and neck, Central retinal artery, Ophthalmic artery

28

: In transarterial embolization of anterior cranial fossa and tentorial dural arteriovenous fistula (DAVF), acute angulation of the feeding artery off the internal carotid artery (ICA) may render stable distal catheterization and, therefore, successful transarterial treatment difficult. In some anatomic dispositions, following selection of the feeding artery, subsequent forward force may lead to prolapse of the microcatheter into the ICA rather than advancing it into either the ophthalmic artery or the meningohypophyseal trunk.

Concepts: Internal carotid artery, Common carotid artery, External carotid artery, Internal jugular vein, Arteriovenous fistula, Fistula, Arteries of the head and neck, Ophthalmic artery

28

Abstract Purpose: Ocular blood flow dysregulation has been implicated in the pathogenesis of glaucoma. Whereas the effect of single antiglaucoma substances on ocular blood flow has been addressed in various experiments, evidence for fixed combinations is sparse. In the present study, we set out to compare the effects of latanoprost 0.005%/timolol 0.5% (LT) fixed combination and brimonidine 0.2%/timolol 0.5% (BT) fixed combination on intraocular pressure (IOP) and ocular blood flow. Methods: In the present study, which followed a randomized, double-masked 2-way crossover design, 16 patients with primary open-angle glaucoma and 2 patients with ocular hypertension were included. The patients underwent a 6-week treatment with LT and a 6-week treatment with BT after a washout for previous antiglaucoma medication. Optic nerve head blood flow (ONHBF) was measured using laser Doppler flowmetry; retrobulbar flow velocities were measured using color Doppler imaging in the ophthalmic artery, the central retinal artery, and the posterior ciliary arteries. IOP was measured at 8 AM, 12 PM, and 4 PM. Results: The mean baseline IOP was 25.3±2.8 mmHg. Both drugs were equally effective in reducing IOP (LT: -35.0%±10.0%; BT: -33.6%±8.8%, P=0.463 between groups). In addition, no difference in ocular perfusion pressure was observed between the 2 treatment groups (P=0.1, between groups). Neither LT nor BT altered ONHBF (P=0.4, baseline vs. treatment) and no effect on flow velocities in the retrobulbar vessels was seen with either of the 2 treatments. Conclusions: In the present study, a 6-week treatment with LT or BT was equally effective in reducing IOP. In addition, none of the administered drugs induced a significant effect on ocular blood flow parameters.

Concepts: Clinical trial, Blood, Crossover study, Retina, Intraocular pressure, Glaucoma, Arteries of the head and neck, Ophthalmic artery

28

BACKGROUND:: The Pipeline embolization device (PED) is the latest technology available for intracranial aneurysm treatment. OBJECTIVE:: To report early postmarket results with the PED. METHODS:: This study was a prospective registry of patients treated with PEDs at 7 American neurosurgical centers subsequent to Food and Drug Administration approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and periprocedural events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications. RESULTS:: Sixty-two PED procedures were performed to treat 58 aneurysms in 56 patients. Thirty-seven of the aneurysms (64%) treated were located from the cavernous to the superior hypophyseal artery segment of the internal carotid artery; 22% were distal to that segment, and 14% were in the vertebrobasilar system. A total of 123 PEDs were deployed with an average of 2 implanted per aneurysm treated. Six devices were incompletely deployed; in these cases, rescue balloon angioplasty was required. Six periprocedural (during the procedure/within 30 days after the procedure) thromboembolic events occurred, of which 5 were in patients with vertebrobasilar aneurysms. There were 4 fatal postprocedural hemorrhages (from 2 giant basilar trunk and 2 large ophthalmic artery aneurysms). The major complication rate (permanent disability/death resulting from perioperative/delayed complication) was 8.5%. Among 19 patients with 3-month follow-up angiography, 68% (13 patients) had complete aneurysm occlusion. Two patients presented with delayed flow-limiting in-stent stenosis that was successfully treated with angioplasty. CONCLUSION:: Unlike conventional coil embolization, aneurysm occlusion with PED is not immediate. Early complications include both thromboembolic and hemorrhagic events and appear to be significantly more frequent in association with treatment of vertebrobasilar aneurysms. ABBREVIATIONS:: ICA, internal carotid arteryPED, Pipeline embolization devicePITA, Pipeline for the Intracranial Treatment of AneurysmsPUFS, Pipeline for Uncoilable or Failed AneurysmsTEE, thromboembolic event.

Concepts: Atherosclerosis, Internal carotid artery, Common carotid artery, Radiology, Aneurysm, Arteries of the head and neck, Circle of Willis, Ophthalmic artery

28

PURPOSE: Review our experience in the use of indocyanine green (ICG) enhanced transpupillary thermotherapy (TTT) in combination with ophthalmic artery chemosurgery for retinoblastomas unresponsive to standard TTT. METHODS: Single centre, retrospective study of 16 eyes in 13 retinoblastoma patients treated with TTT and ICG via indirect ophthalmoscope: 23 treatments of 16 eyes, with a mean follow-up of 12.1 months (range 3-35 months). Outcome measures included tumour response and electroretinogram. RESULTS: Treatment resulted in significant tumour regression in all eyes: 13 eyes with well-differentiated characteristics, 2 with implanting vitreous seeds and 1 eye refractory to traditional TTT. ERG function was retained in all eyes. CONCLUSIONS: ICG-enhanced TTT with ophthalmic artery chemosurgery can effectively treat retinoblastoma refractory to conventional focal treatments without deleterious ocular side effects.

Concepts: Retina, Eye, Ophthalmology, Vitreous humour, Indocyanine green, Optic disc, Ophthalmic artery, Ophthalmoscope

27

: During evaluation for monocular visual loss, a 48-year-old woman was found to have a posttraumatic paraophthalmic internal carotid artery (ICA) pseudoaneurysm. She underwent reconstruction of the ophthalmic segment of the right ICA with a Pipeline embolization device but her vision did not return.

Concepts: Internal carotid artery, Common carotid artery, External carotid artery, Ophthalmology, Carotid sinus, Internal jugular vein, Ophthalmic artery, Amaurosis fugax

27

Ragauskas et al.(1) demonstrated that when external pressure is applied, the orbit tends to equilibrate flow in the ipsilateral ophthalmic artery (OA) when its level approaches intracranial pressure (ICP). The authors detected this relationship by making the OA into a “natural pair of scales, in which the intracranial segment of the OA is compressed by extracranial pressure (Pe) applied to the orbit.”

Concepts: Intracranial pressure, Skull, Clinical psychology, Absolute value, Ophthalmic artery, Lacrimal gland

27

PURPOSE.: To assess the benefits of using a low-frequency convex probe and detecting ophthalmic artery blood flow for the differential diagnosis of occlusion from severe stenosis of the internal carotid artery (ICA). METHODS.: A total of 103 patients were enrolled and had three sequential examinations by an experienced sonographer. First, the proximal ICA was examined with a 5.0-7.5-MHz linear probe. Second, the distal ICA was examined with a 3.5-5.0-MHz convex probe. Third, the ophthalmic artery (OA) was examined with a 5.0-7.5-MHz linear probe. Three parallel sets of diagnoses were made based on results from (1) high-frequency ultrasonography; (2) combined use of high- and low-frequency ultrasonography; and (3) combined use of high- and low-frequency ultrasonography along with OAs examination findings. Efficiencies of the three diagnoses were compared by receiver operating characteristic curves with digital subtraction angiography as the gold standard. RESULTS.: The second diagnostic approach yielded the highest sensitivity (96.6%) and specificity (94.5%). OA blood flow was reversed in most, but not all, cases of ICA occlusion (27/29). Areas under the receiver operating characteristic curves of the three diagnoses were significantly different (p < 0.05). CONCLUSIONS.: The diagnostic performance of combined high- and low-frequency ultrasonography is greater than that of high-frequency ultrasonography alone. Although OA examination does not increase the diagnostic performance, it provides helpful data for the assessment of hemodynamics and collateral circulation. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012.

Concepts: Medical terms, Internal carotid artery, Common carotid artery, Radiology, Medical ultrasonography, Digital subtraction angiography, Intravenous digital subtraction angiography, Ophthalmic artery