Amit Herwadkar

Visual pathway compromise after hydrocoil treatment of large ophthalmic aneurysms.

OBJECTIVEHydrogel-coated coils (MicroVention, Inc., Aliso Viejo, CA) for endovascular aneurysm treatment offer the theoretical advantages of increased volumetric occlusion, thrombus stabilization, and improved neointimal healing. Reports of local inflammation and hydrocephalus after coiling of unruptured aneurysms have raised questions about the safety profile or appropriate usage of these new devices. CLINICAL PRESENTATIONTwo patients with large ophthalmic aneurysms underwent elective endovascular coiling with HydroCoils. Three to 4 weeks later, they developed profound, progressive bilateral visual loss. Magnetic resonance imaging scans demonstrated extensive enhancement of the coil ball, surrounding brain parenchyma, and optic chiasm, with perianeurysmal edema. INTERVENTIONDexamethasone produced impressive but temporary improvement in vision in one patient; the other experienced only minor improvement. One patient also developed hydrocephalus; ventriculoperitoneal shunting reduced ventricular size but had no effect on vision. Follow-up imaging demonstrated persistent enhancement of the coil ball, as well as recurrence and extension of the abnormal signal in the parenchyma and along the optic tract. CONCLUSIONBoth patients have been left with no functional vision in the eye ipsilateral to the aneurysm and have experienced marked visual field loss and reduced acuity in the contralateral eye. Ongoing international studies will provide more information on the rate of inflammatory complications. The biological mechanisms underlying the phenomenon also require investigation. Meanwhile, we caution against using HydroCoils in situations in which worsened mass effect or local inflammation would have highly deleterious consequences, such as in large aneurysms adjacent to the visual pathways or the brainstem.

Incidental finding of fenestration of the supraclinoid internal carotid artery with appearances on magnetic resonance angiography

A case of incidentally diagnosed fenestration of the supraclinoid internal carotid artery (ICA) with an associated aneurysm is presented. We present appearances on magnetic resonance angiography, which have not been previously described. Careful interrogation of the data in volume-rendered and multiplanar reformats was required to make the diagnosis. The relationship between fenestrations and aneurysms in the anterior circulation is discussed both in general terms and with specific regard to the supraclinoid ICA. We also review the embryology of the distal ICA, which may help explain the adult anatomy of this rare lesion as a failure of caudal separation of the rostral and caudal divisions of the primitive distal ICA.

Double origin of the posterior inferior cerebellar artery with findings on conventional and CT angiography

A case of double origin of the posterior inferior cerebellar artery (PICA) is presented, with appearances on both cross-sectional imaging and conventional angiography. An associated aneurysm was found, strengthening the belief that this variation is associated with intracranial aneurysms. Furthermore, this is the first report of a right-sided double-origin PICA in a female patient, which calls into question the previously proposed male and left-sided preponderance of this variation.

Isolated extradural Rosai-Dorfman disease of the thoracic spine: a rare cause of spinal cord compression: case report.

OBJECTIVERosai-Dorfman disease is a rare benign histiocytic disease of unknown origin that arises predominantly in lymph nodes with generalized fever and malaise but can affect a variety of organs. We describe a case of isolated Rosai-Dorfman disease causing thoracic cord compression. CLINICAL PRESENTATIONA 24-year-old man presented with progressive spastic paraparesis. A magnetic resonance scan revealed an anteriorly placed extradural lesion of the T4-T7 thoracic spine causing cord compression. He was systemically well with no other disease. INTERVENTIONThe patient made a complete recovery after a limited T4-T7 laminectomy and biopsy of the lesion. Repeat magnetic resonance scan at 6 months revealed a further posteriorly placed lesion at the T8/9 level. More extensive posterior surgery was carried out with subtotal resection of the lesion with pedicle screw fixation. Histologically, all specimens revealed fibrous connective tissue infiltrated by histiocytic cells with CD68 and S100 positivity, confirming a diagnosis of Rosai-Dorfman disease. CONCLUSIONSThis is a rare case of isolated Rosai-Dorfman disease causing thoracic cord compression. It should be considered among the differential diagnoses of extradural cord compression. Radiological features and treatment options are discussed.

The expanding role of interventional radiology in head and neck surgery

Interventional radiology is defined by the Society of Interventional Radiology as ‘the delivery of minimally invasive, targeted treatments, performed using imaging for guidance’. Although the principles of angiography for diagnosis have existed since the 1920s, and today remain a well-established modality for the diagnosis of many common conditions, it was not until the 1960s that the American Charles Dotter, and other pioneers, extended these techniques from diagnosis to treatment.1 Their foresight, together with ever-increasing technological capability, allowed the use of transluminal angioplasty for the treatment of peripheral vascular disease and led Dotter to say, in 1964, that ‘it should be evident that the vascular catheter can be more than a tool for passive means for diagnostic observations: used with imagination it can become an important surgical instrument’.2,3 Thus, interventional radiology as a specialty was born. Work on the cerebral vasculature began in the 1970s, largely for neurosurgical conditions. It is perhaps not surprising that the initial, and still best known, uses of interventional radiology were for the highly accessible vascular system, and for the type of non-vascular conditions that offered poor surgical access, such as in neurosurgery. More recently, interventional radiology techniques have been applied to head and neck cancer patients, initially with the use of detachable balloon occlusion in patients with laryngeal cancer and impending carotid artery rupture. From this, the range of applications of interventional radiology in the extra-cranial head and neck has continued to evolve and expand. These applications include line placement, foreign body removal, placement of feeding tubes (primary gastrostomy, gastrojejunostomy or jejunostomy tubes), and oesophageal or bronchial dilatation and stenting. The main focus of this review is on the vascular applications of interventional radiology in the head and neck, which can be divided into three main categories: management of acute haemorrhage (e.g. epistaxis, carotid blowout); management of vascular lesions (e.g. tumours, arterio-venous malformations); and venous sampling.

A Case of a Spontaneous Intraorbital Arteriovenous Fistula: Clinico-Radiological Findings and Treatment by Transvenous Embolisation via the Superior Ophthalmic Vein

Abstract A 72-year-old male presented with progressive right axial proptosis and red eye. Catheter angiography demonstrated an intraorbital arteriovenous fistula (IAVF) distal to the central retinal artery (CRA). Transvenous embolisation following direct surgical exposure of the superior ophthalmic vein (SOV) resulted in rapid resolution of his symptoms and signs. Transvenous embolisation via the SOV is a safe, effective alternative to transarterial embolisation for treating spontaneous IAVF where transarterial embolisation poses a risk of CRA occlusion.

Pituitary adenoma and incidental superior hypophyseal aneurysm.

In patients with pituitary adenomas, intra-cranial aneurysms can be an incidental finding, and are usually located outside the pituitary region. The authors describe the multi-modal management of a rare case of an aneurysm of the supraclinoid carotid that encroached into a pituitary macroadenoma.

Posterior Inferior Cerebellar Artery/Vertebral Artery Subarachnoid Hemorrhage: A Comparison of Saccular vs Dissecting Aneurysms

BACKGROUND Two distinct categories of aneurysms are described in relation to the posterior inferior cerebellar artery (PICA) and vertebral artery (VA): saccular (SA) and dissecting (DA) types. This distinction is often unrecognized because abnormalities here are uncommon and most studies are small. OBJECTIVE To determine if there are any differences in the clinical presentation, in‐hospital course, or outcomes in patients with DA vs SA of the PICA or VA. METHODS Thirty‐eight patients with a VA or PICA aneurysm were identified from a departmental subarachnoid hemorrhage database and categorized into DA or SA types. Prospectively collected demographic and outcome data (length of stay, discharge Glasgow Outcome Score) were supplemented by abstracting records for procedural data (extraventricular drain [EVD], ventriculoperitoneal [VP] shunt, tracheostomy, and nasogastric feeding). Univariate, binary logistic regression, and Cox regression analysis was used to compare patients with SA vs DA. RESULTS Three aneurysms related to arteriovenous malformation were excluded. Five patients were conservatively managed. Of the 30 treated cases, more patients with a DA presented in poor grade (6/13 vs 2/17 SA; P = .035). More DA patients required an EVD (85% vs 29%; P = .003), VP shunt (54% vs 6%; P = .003), tracheostomy (46% vs 6%; P < .01), and nasogastric feeding (85% vs 35%; P = .007). The median length of stay (41 vs 17 d, P < .001) was longer, and the age and injury severity adjusted odds of discharge home were significantly lower in the DA group (P = .008). Thirty‐day mortality was not significantly different (23% of DA vs 24% of SA; P = .2). CONCLUSION The presentation, clinical course, and outcomes differ in patients with DA vs SA of the PICA and VA.

Hypoglossal Nerve Palsy Due to Internal Carotid Artery Dissection

A 40-year-old man presented with a 2-week history of headache followed by 5 days of mild dysarthria. He had no history of trauma and no preceding symptoms. The patient’s tongue deviated to the left (Figure 1A) with no other neurological signs. Magnetic resonance (MR) imaging of the brain was normal and contrast-enhanced MR angiogram demonstrated narrowing of the left internal carotid artery (ICA; red arrow Figure 1D) lumen associated with high signal intramurally and expansion suggesting dissection (yellow arrow) and pseudoaneurysm (yellow/blue arrows; Figure 1C and D). Treatment was with aspirin 300 mg for 2 weeks followed by 75 mg daily. There was good resolution of symptoms and tongue deviation (Figure 1B) at 3 months. Repeat arterial imaging showed persisting ICA (red) pseudoaneurysm (blue; Figure 1E). The incidence of spontaneous cervical artery dissection is around 2.5 to 5 per 100 000, causing up to 25% of stroke in younger populations. Cases sometimes cause isolated cranial nerve palsies, most frequently CNXII. The hypoglossal nerve provides motor innervation to the tongue and arises from the ventral surface of the medulla; it then traverses the hypoglossal canal. On exiting the canal, the nerve runs beneath the ICA and the internal jugular vein. The relationship between the nerve and ICA explains how mural expansion may cause nerve compression. Not all dissection results in vascular expansion, however. Sometimes it is the nutrient arteries which become occluded by vessel wall damage, or distal embolization. We suspect a nutrient artery lesion in our case due to clinical improvement without aneurysm resolution.

Varicella zoster virus cerebral aneurysmal vasculopathy presenting in a newly-diagnosed HIV-positive patient

We report the case of a newly-diagnosed HIV-positive patient with varicella zoster virus aneurysmal vasculopathy confirmed on intrathecal antibody testing, despite a negative Cerebrospinal fluid (CSF) Varicella Zoster Virus (VZV) Polymerase Chain Reaction (PCR). This highlights the importance of prompt treatment with antiviral and steroid therapy in the presence of clinical or radiological suspicion whilst awaiting further confirmatory testing.