Cavernous Malformation of the Optic Nerve and Chiasm: Prompt Suspicion and Surgery Matter.

BACKGROUND: Cavernous malformations (CMs) of the optic nerve and chiasm are extremely rare, accounting for less than 1% of all intracranial CMs. Acute, subacute, or progressive visual loss from CM may occur with or without hemorrhage. Prompt surgical excision of the CM offers the best hope to improve or stabilize vision. Given its rarity, optic nerve and chiasm CMs may not be readily suspected. We provide 3 cases of optic nerve and chiasm CM, highlighting key neuroimaging features and the importance of expedited intervention. METHODS: Case records of the neuro-ophthalmology clinics of the Bascom Palmer Eye Institute and the University of Colorado, and literature review of reported cases of optic CM. RESULTS: A 49-year-old woman reported acute progressive painless vision loss in the right eye. MRI showed a suprasellar mass with heterogeneity in signal involving the right prechiasmatic optic nerve. Surgical excision of the CM 5 days after onset of visual loss improved vision from 20/300 to 20/30. A 29-year-old woman with acute painless blurred vision in the right eye had anterior chiasmal junctional visual field defects corresponding to a heterogeneously minimally enhancing mass with blood products enlarging the optic chiasm and proximal right optic nerve. Surgical excision of the CM 8 weeks after onset of visual loss improved vision from 20/40 to 20/15 with improved visual fields. A 33-year-old woman with a history of familial multiple CMs, diagnosed at age 18, reported new-onset severe headache followed by blurred vision. MRI showed a hemorrhagic lesion of the optic chiasm and right optic tract. She was 20/20 in each eye with a reported left superior homonymous hemianopia. No intervention was recommended. Vision of the right eye worsened to 20/400 2 months later. The patient was followed over 13 years, and the MRI and visual function remained unchanged. Literature review yielded 87 optic CM cases occurring across gender and nearly all ages with visual loss and headache as the most common presenting symptoms. Optic chiasm is the most common site of involvement (79%). Nearly 95% of reported CM cases were treated with surgery with 81% with improved vision and 1% with worsened vision. CONCLUSION: MRI features are critical to the diagnosis of optic nerve and chiasm CM and may mimic other lesions. A high index of suspicion by the neuro-ophthalmologist and neuroradiologist leads to early recognition and intervention. Given optic CM displaces and does not infiltrate neural tissue, expedited surgical resection by a neurosurgeon after consideration of other diagnostic possibilities improves visual function in most cases.

An academic center's delivery of care after the Haitian earthquake.

The Miller School of Medicine of the University of Miami and Project Medishare, an affiliated not-for-profit organization, provided a large-scale relief effort in Haiti after the earthquake of 12 January 2010. Their experience demonstrates that academic medical centers in proximity to natural disasters can help deliver effective medical care through a coordinated process involving mobilization of their own resources, establishment of focused management teams at home and on the ground with formal organizational oversight, and partnership with governmental and nongovernmental relief agencies. Proximity to the disaster area allows for prompt arrival of medical personnel and equipment. The recruitment and organized deployment of large numbers of local and national volunteers are indispensable parts of this effort. Multidisciplinary teams on short rotations can form the core of the medical response.

Spinal imaging findings in spontaneous intracranial hypotension.

OBJECTIVE: spontaneous intracranial hypotension is a syndrome of postural headaches that arises as a result of CSF leakage and without previous lumbar puncture. The purpose of this study was to review and describe the spinal imaging findings of this entity. MATERIALS AND METHODS: The spinal MRI and CT myelographic imaging findings of 13 patients with spontaneous intracranial hypotension were retrospectively reviewed. Spinal images were evaluated for spinal fluid collections, dural enhancement, dilated epidural veins, a thickened or enlarged ventral lateral epidural venous plexus, high T2 signal intensity between the spinous processes of C1 and C2 (C1-C2 sign), structural abnormalities, canal attenuation or cord compression, and active contrast extravasation. When available, brain MRI findings were reviewed. Surgical correlation was made in the cases of four patients. RESULTS: The patients were found to have spinal fluid collections (11 of 13 patients), dural enhancement (eight of 10 patients undergoing contrast administration), dilated epidural veins (10 of 13 patients), an enlarged epidural venous plexus (nine of 13 patients), C1-C2 sign (seven of 13 patients), structural abnormalities (four of 13 patients), canal attenuation or cord compression (five of 13 patients), and active contrast extravasation (four of 13 patients). CONCLUSION: Spinal imaging is likely to show one or more findings in patients with spontaneous intracranial hypotension and may be of particular value to patients with equivocal clinical or brain imaging findings and patients who need surgery. Encountering these findings on spinal images may suggest the diagnosis of spontaneous intracranial hypotension and therefore can influence patient treatment.

Acute abducens nerve palsy in a patient with the novel coronavirus disease (COVID-19).

We present a case of an abducens nerve palsy in a previously healthy young man in the setting of SARS-CoV-2 infection. Magnetic resonance imaging obtained 5 weeks after the onset of diplopia demonstrated an atrophic left lateral rectus muscle, which was hyperintense on T2 weighting, consistent with denervation. Although the mechanism of the nerve palsy remains unclear, it is suspected to be related to his viral illness, because the patient had no preexisting vascular risk factors or evidence of other neurologic disease on neuroimaging. Cranial nerve palsies may represent part of the neurologic spectrum of COVID-19.

Evaluation of an integrated orbital tissue expander in an anophthalmic feline model.

PURPOSE: To evaluate the anatomical effects and tissue biocompatibility in a feline model of an integrated orbital tissue expander (OTE) designed to stimulate bone growth in an anophthalmic socket. DESIGN: An animal study was performed in cats to assess orbital bone growth with and without an OTE. METHODS: The OTE is an inflatable (0.5 to >6.0 cm(3)) polymeric globe sliding on a titanium T plate secured to the lateral orbital rim with screws. Eight cats had left eye enucleation at age two weeks, with five orbits receiving an OTE and the remaining three serving as nonimplanted controls. Serial transconjunctival implant inflation was performed by injecting normal saline solution into the OTE to a final volume of 3.5 ml. Serial computed tomographic scans were obtained to assess socket growth. All eight cats were euthanized at 18 weeks and dry skulls prepared. The effective orbital volume was measured by inflating an OTE in the orbit of a dry skull until it filled the cavity completely. RESULTS: Three cats periodically scratched open the tarsorrhaphy and conjunctiva to rupture the OTE, which resulted in implant exchanges. At 18 weeks, the OTE expanded orbital volume was approximately 18% smaller than the normal contralateral side. In the control animals, the anophthalmic orbital volume was approximately 66% smaller than the contralateral orbit. Histopathology of orbital tissues showed no evidence of foreign body reaction. CONCLUSIONS: This proof-of-concept pilot study demonstrated implant efficacy in cats, and no implant-related adverse effects were observed. OTE has the potential to stimulate bone growth in human anophthalmic orbits.

Is a Persistent Vacuum Phenomenon a Sign of Pseudarthrosis After Posterolateral Spinal Fusion?

The purpose of this study is to evaluate whether the vacuum phenomenon (VP) resolves after posterolateral lumbar fusion, and whether persistence of VP is indicative of failed fusion. We retrospectively reviewed patients with degenerative lumbar spinal stenosis with instability with a positive VP on preoperative computed tomography (CT) who underwent posterolateral lumbar spinal fusion. Lumbar CT and radiographs were evaluated for the presence of VP and fusion at each level. Thirty-six positive VP levels were identified on the preoperative lumbar CT at the levels in the fusion in 18 patients. The mean age at surgery was 67.6 ± 9.4 years and mean follow-up was 1.6 ± 0.86 years. Fusion was seen at 32 levels (88.9%). Of the 15 levels where VP persisted, evidence of fusion was seen in 13 levels and pseudarthrosis was seen at 2. Of the 21 levels where VP disappeared, fusion was seen at 19 levels and pseudarthrosis was seen at 2 .There was no significant difference between the 2 groups (P > .05). We did not find an association between persistence of VP and pseudarthrosis. Persistence of VP after spinal fusion may not be an indicator of pseudarthrosis, and should not be misinterpreted as an indication for additional surgery.

Hematogenous brain metastasis in children.

Hematogenous brain metastases are uncommon in childhood. Three patients and a literature review that includes centers reporting up to 36 years of experience are presented in this study. The total of 2,040 patients includes our three examples of one neuroblastoma, one hepatoblastoma, and one adrenal carcinoma. Cerebral hematogenous metastases were reported in 4.4% of 429 patients with neuroblastoma, 1.9% of 574 rhabdomyosarcoma patients, 6.5% of 386 patients with osteosarcoma, 3.3% of 487 Ewing sarcoma patients, 3.6% of 44 melanoma patients, 13.5% of 37 patients with germ cell tumors, and 1.3% of the 78 patients with Wilms tumor. Five miscellaneous patients included three with a hepatoblastoma and one each with adrenal carcinoma and nephroma. All of the large series reports have been published in oncology journals.

Whole-brain proton MR spectroscopic imaging of mild-to-moderate traumatic brain injury and correlation with neuropsychological deficits.

Changes in the distribution of the magnetic resonance (MR)-observable brain metabolites N-acetyl aspartate (NAA), total choline (Cho), and total creatine (Cre), following mild-to-moderate closed-head traumatic brain injury (mTBI) were evaluated using volumetric proton MR spectroscopic imaging (MRSI). Studies were carried out during the subacute time period following injury, and associations of metabolite indices with neuropsychological test (NPT) results were evaluated. Twenty-nine subjects with mTBI and Glasgow Coma Scale (GCS) scores of 10-15 were included. Differences in individual metabolite and metabolite ratio distributions relative to those of age-matched control subjects were evaluated, as well as analyses by hemispheric lobes and tissue types. Primary findings included a widespread decrease of NAA and NAA/Cre, and increases of Cho and Cho/NAA, within all lobes of the TBI subject group, and with the largest differences seen in white matter. Examination of the association between all of the metabolite measures and the NPT scores found the strongest negative correlations to occur in the frontal lobe and for Cho/NAA. No significant correlations were found between any of the MRSI or NPT measures and the GCS. These results demonstrate that significant and widespread alterations of brain metabolites occur as a result of mild-to-moderate TBI, and that these measures correlate with measures of cognitive performance.