Intracranial transthecal subarachnoid fat emboli and subarachnoid haemorrhage arising from a sacral fracture and dural tear

We present the case of a 28-year-old man with an unusual aetiology of lipid-dense material in the subarachnoid space. CT of the head at presentation was normal. MRI of the spine revealed a defect in the dura at L5/S1, with avulsed left L5 and S1 nerve roots. Haematoma and marrow fat were observed in close relation to the dural tear adjacent to the sacral fracture. Head CT and MRI subsequently demonstrated new lipid-dense material and haemorrhage in the subarachnoid space after sacral instrumentation, presumably owing to transthecal displacement of fatty marrow.

Resolution of existing intimal plaque in a patient with carotidynia

We present a case of carotidynia that was imaged with 3 techniques: sonography, CT angiography, and gadolinium-enhanced MR imaging. We describe a previously unreported finding, the resolution of an intimal plaque noted on imaging at the time of initial presentation, presumably due to changes induced by the healing phase of the carotid inflammatory process.

Lightning strike: a rare cause of bilateral ossicular disruption

Otologic injury associated with fatal and nonfatal lightning strikes has been sporadically reported in the literature. The most common acoustic insult is a conductive hearing loss secondary to rupture of the tympanic membrane. Although conjecture has been made of the theoretic possibility of ossicular injury from lightning strike, to our knowledge, none has been demonstrated intraoperatively or postmortem. We report the first documented case of ossicular disruption in a lightning-strike victim.

Accuracy and safety of pedicle screw fixation in thoracic spine trauma

OBJECT

The authors evaluated the accuracy of placement and safety of pedicle screws in the treatment of unstable thoracic spine fractures.

METHODS

Patients with unstable fractures between T-1 and T-10, which had been treated with pedicle screw (PS) placement by one of five spine surgeons at a referral center were included in a prospective cohort study. Postoperative computed tomography scans were obtained using 3-mm axial cuts with sagittal reconstructions. Three independent reviewers (C.B., V.S., and D.G.) assessed PS position using a validated grading scale. Comparison of failure rates among cases grouped by selected baseline variables were performed using Pearson chi-square tests. Independent peri- and postoperative surveillance for local and general complications was performed to assess safety. Twenty-three patients with unstable thoracic fractures treated with 201 thoracic PSs were analyzed. Only PSs located between T-1 and T-12 were studied, with the majority of screws placed between T-5 and T-10. Of the 201 thoracic PSs, 133 (66.2%) were fully contained within the pedicle wall. The remaining 68 screws (33.8%) violated the pedicle wall. Of these, 36 (52.9%) were lateral, 27 (39.7%) were medial, and five (7.4%) were anterior perforations. No superior, inferior, anteromedial, or anterolateral perforations were found. When local anatomy and the clinical safety of screws were considered, 98.5% (198 of 201) of the screws were probably in an acceptable position. No baseline variables influenced the incidence of perforations. There were no adverse neurological, vascular, or visceral injuries detected intraoperatively or postoperatively.

CONCLUSIONS

In the vast majority of cases, PSs can be placed in an acceptable and safe position by fellowship-trained spine surgeons when treating unstable thoracic spine fractures. However, an unacceptable screw position can occur.

Utility of Screening for Blunt Vascular Neck Injuries with Computed Tomographic Angiography

PURPOSE

To prospectively study the impact of implementing a computed tomographic angiography (CTA)-based screening protocol on the detected incidence and associated morbidity and mortality of blunt vascular neck injury (BVNI).

METHODS

Consecutive blunt trauma patients admitted to a single tertiary trauma center and identified as at risk for BVNI underwent admission CTA using an eight-slice multi-detector computed tomography scanner. The detected incidence, morbidity, and mortality rates of BVNI were compared with those measured before CTA screening. A logistic regression model was also applied to further evaluate potential risk factors for BVNI.

RESULTS

A total of 1,313 blunt trauma patients were evaluated. One hundred seventy screening CTAs were performed, of which 33 disclosed abnormalities. Twenty-three were evaluated angiographically, of which 15 were considered to have significant BVNIs, as were 4 of the 10 patients with abnormal CTAs and no angiogram. The incidence of angiographically proven BVNIs in our series was 1.1%. If four patients who were treated for BVNIs based on CTA alone are included, the incidence rises to 1.4%. This is significantly higher than the 0.17% incidence before screening (p < 0.001). In addition, the delayed stroke rate and injury-specific mortality fell significantly from 67% to 0% (p < 0.001) and 38% to 0% (p = 0.002), respectively. Overall mortality also fell significantly, from 38% to 10.5% (p = 0.049). Univariate logistic regression identified the presence of cervical spine injury as a significant predictor of BVNI (p < 0.001).

CONCLUSION

CTA screening increases the detected incidence of BVNI 8-fold, with rates similar to angiographically based screening protocols. CTA screening significantly decreases BVNI-related morbidity and mortality in an efficient manner, underlying its utility in the early diagnosis of this injury.

Clinical exacerbation of multiple sclerosis following radiotherapy

BACKGROUND

Radiation of the central nervous system in patients with demyelinating disease may have deleterious effects.

OBJECTIVE

To describe a 30-year-old woman with multiple sclerosis who developed an attack of demyelination 2 months following radiotherapy for a parotid malignancy.

RESULTS

Magnetic resonance imaging demonstrated new hyperintense lesions that corresponded to both the localization of the patient's symptoms and to the area defined by the 50% isodose radiation field.

CONCLUSION

Radiation treatment likely triggered an exacerbation of multiple sclerosis.

Intravenous tissue plasminogen activator for acute ischemic stroke: A Canadian hospital's experience

BACKGROUND AND PURPOSE

In the United States, tissue plasminogen activator (tPA) was approved for treatment of acute ischemic stroke in 1996. Its use has only recently been approved in Canada. We sought to evaluate the safety, feasibility, and efficacy of treatment in a Canadian hospital setting.

METHODS

A combined retrospective and prospective review is presented of 46 consecutive patients treated with intravenous tPA at our hospital with a treatment protocol similar to that of the National Institute of Neurological Disorders and Stroke (NINDS) trial.

RESULTS

Symptomatic intracranial hemorrhage at 36 hours occurred in 1 patient (2.2%). The median time to treat was 165 minutes, with a median "door-to-needle" time of 84 minutes. Compared with patients presenting initially at our hospital, patients transferred from another institution for tPA therapy were treated closer to the 3-hour time window (mean 173 versus 148 minutes, P:<0.001) but had a shorter door-to-needle time (43 versus 102 minutes, P:<0.001). For every 10 minutes closer to the 3-hour time window that any patient arrived at the hospital, 7 minutes was saved in the door-to-needle time (correlation coefficient 0.9, P:<0.001). Patient outcome did not differ from that in the NINDS trial (P:>0.75).

CONCLUSIONS

Our safety and patient outcome data compare favorably with NINDS and Phase IV data. Although a 3-hour treatment window was feasible, the median door-to-needle time lengthened as more treatment time was available and the door-to-needle time was beyond recommended standards. This review has prompted changes in our community to improve treatment efficiency.

Combined venous lymphatic malformations of the orbit (so-called lymphangiomas). Association with noncontiguous intracranial vascular anomalies

OBJECTIVE

The authors present seven cases of orbital combined venous lymphatic vascular malformations (CVLVM) (lymphangioma) with evidence of noncontiguous intracranial vascular anomalies.

DESIGN

The study design was a review.

MAIN OUTCOME MEASURES

Radiologic studies of 25 patients with combined venous lymphatic vascular malformations were evaluated for noncontiguous intracranial vascular anomalies. Features of the intracranial anomalies and orbital lesions, their clinical presentation, and prognosis are described.

RESULTS

Seven patients (28%) had associated noncontiguous intracranial vascular anomalies. Intracranial hemorrhage occurred in one of these patients. The intracranial anomalies had radiologic characteristics of developmental venous anomalies (DVAs). Diffuse orbital lesions with superficial and deep components (7/7), orbital bony expansion (7/7), and intraconal and extraconal components (4/7) were most common. They involved the inferior orbital fissure and extended into the pterygopalatine fossa in five patients. Involvement of the superior orbital fissure was noted in all seven patients with extension into the middle cranial fossa in three patients. At birth, these patients generally had a visible superficial component and then had episodes of sudden proptosis associated with deep orbital hemorrhages. Visual outcome was poor (20/200 or less) in four (57%) of seven cases. Anterior extension into soft tissues of the face and forehead and other associated vascular lesions, such as palatal involvement, were relatively common. In contrast, CVLVMs (lymphangiomas) without noncontiguous intracranial vascular anomalies were more anterior, less diffuse, less likely to extend into the soft tissues of the face, have associated vascular lesions, or have a poor visual outcome.

CONCLUSIONS

Orbital CVLVMs (lymphangiomas) may be associated with noncontiguous intracranial vascular anomalies that may bleed. This association with intracranial DVAs has not been reported previously. The intracranial vasculature should be evaluated prospectively in these lesions, especially if they are diffuse.

In vivo visualization of myelin water in brain by magnetic resonance

We exploit the intrinsic difference in magnetic resonance spin-spin relaxation time, T2, between water associated with myelin sheaths and water in other central nervous system tissue in order to measure myelin water content within any region of an image or to generate indirectly a myelin map of the brain. In normal volunteers, myelin water maps give the expected myelin distribution. In multiple sclerosis patients, lesions exhibit different myelin water contents providing insight into the demyelination process unavailable from conventional magnetic resonance images. In vivo myelin measurement has important applications in the clinical management of multiple sclerosis and other white matter diseases.

The role of prophylactic brain irradiation in limited stage small cell lung cancer: clinical, neuropsychologic, and CT sequelae

Ninety-four patients with limited stage small cell lung cancer treated between 1981 and 1985 with a regimen including prophylactic brain irradiation (PBI) after combination chemotherapy were assessed for compliance with PBI, brain relapse, and neurologic morbidity. Seventy-seven percent of patients had PBI and of these, 22% developed brain metastases after a median time of 11 months post treatment. The brain was the apparent unique initial site of relapse in 10% of PBI cases but more commonly brain relapse was preceded or accompanied by failure at other sites, especially the chest. Brain metastases were the greatest cause of morbidity in 50% of PBI failures. Twelve of 14 PBI patients alive 2 years after treatment had oncologic, neurologic, and neuropsychological evaluation, and brain CT. All long-term survivors were capable of self care and none fulfilled diagnostic criteria for dementia, with three borderline cases. One third had pretreatment neurologic dysfunction and two thirds post treatment neurologic symptoms, most commonly recent memory loss. Fifty percent had subtle motor findings. Intellectual functioning was at the 38th percentile with most patients having an unskilled occupational history. Neuropsychologic impairment ratings were borderline in three cases and definitely impaired in seven cases. CT scans showed brain atrophy in all cases with mild progression in those having a pre-treatment baseline. Periventricular and subcortical low density lesions identical to the CT appearance of subcortical arteriosclerotic encephalopathy were seen in 82% of posttreatment CT studies, and lacunar infarcts in 54%. Neuropsychologic impairment scores and the extent of CT periventricular low density lesions were strongly associated (rank correlation 0.7, p less than .05). Overall, PBI after intensive combination chemotherapy did not induce gross dementia or neurologic dysfunction but its risk/benefit ratio is not overwhelmingly favorable, with failure to prevent brain relapse in 1/5 patients and subtle but detectable motor findings and neuropsychologic impairment in the majority.

Orbital-adnexal lymphangiomas. A spectrum of hemodynamically isolated vascular hamartomas

A retrospective review of 13 cases of lymphangioma has led to a classification of these lesions into categories of superficial, deep, and combined types. The clinical manifestations, prognosis, and management directly correlate with the pathophysiology and the location of the lesions. Superficial lesions consist of isolated multicystic vascular abnormalities of cosmetic significance only. Deep orbital lymphangiomas present as spontaneous, acute proptosis due to retrobulbar hemorrhage. Combined lesions demonstrate both superficial and deep components and are also characterized by spontaneous hemorrhages. Histopathologically, lymphangiomas represent a spectrum of vascular hamartomas with a constellation of features that parallels the clinical progression and histology of similar lesions elsewhere in the head and neck. This may include the presence of diaphanous serous-filled vascular channels, a connective tissue stroma with lymphorrhages, features of old hemorrhage, dysplastic vessels, and random smooth muscle bundles. Both direct and indirect evidence suggests that these lesions are characterized by relative hemodynamic isolation.

Transvascular treatment of giant aneurysms of the cavernous carotid and vertebral arteries. Functional investigation and embolization

Functional angiographic investigation and percutaneous embolization using detachable balloons in nine carotid cavernous aneurysms, three petrous aneurysms, one vertebral artery aneurysm, and one posterior inferior cerebellar aneurysm are reported. A double-lumen balloon catheter is used to evaluate acute tolerance to occlusion of the carotid or vertebral arteries. Occlusion is tested under systemic heparinization. Local perfusion of heparinized saline, proximal as well as distal, to the balloon occlusion is used. The procedure was successful in all but one cavernous aneurysm. The arterial lumen was sacrificed in all cases. Clinical improvement occurred in all successful cases. Retro-orbital pain was relieved in all. Ocular cranial nerve palsies improved or resolved in most. One delayed ophthalmic episode that improved represents the only complication. No such embolic problems occurred in any case in which the cavernous carotid artery was occluded by balloon trapping. The delayed embolic complications after carotid artery occlusion are related to the collateral vessels to the C-4 and C-5 segments of the artery. Balloon trapping decreases the length of the thrombosed segment and prevents retrograde filing of the aneurysm.