Diagnostic challenges in Balamuthia mandrillaris infections.

Balamuthia mandrillaris is an emerging cause of subacute granulomatous amebic encephalitis (GAE). The diagnosis of this infection has proven to be difficult and is usually made postmortem. Early recognition and treatment may offer some benefit. This report describes a previously healthy woman who died from GAE due to B. mandrillaris.

The evolution of pituitary cysts in growth hormone-treated children.

OBJECTIVES: We have previously shown that pituitary cysts may affect growth hormone secretion. This study sought to determine cyst evolution during growth hormone treatment in children. METHODS: Forty-nine patients with short stature, a pituitary cyst, and at least two brain MRI scans were included. The percent of the pituitary gland occupied by the cyst (POGO) was calculated, and a cyst with a POGO of ≤15% was considered small, while a POGO >15% was considered large. RESULTS: Thirty-five cysts were small, and 14 were large. Five of the 35 small cysts grew into large cysts, while 6 of the 14 large cysts shrunk into small cysts. Of 4 cysts that fluctuated between large and small, 3 presented as large and 1 as small. Small cysts experienced greater change in cyst volume (CV) (mean=61.5%) than large cysts (mean=-0.4%). However, large cysts had a greater net change in CV (mean=44.2 mm3) than small cysts (mean=21.0 mm3). Older patients had significantly larger mean pituitary volume than younger patients (435.4 mm3 vs. 317.9 mm3) and significantly larger mean CV than younger patients (77.4 mm3 vs. 45.2 mm3), but there was no significant difference in POGO between groups. CONCLUSIONS: Pituitary cyst size can vary greatly over time. Determination of POGO over time is a useful marker for determining the possibility of a pathologic effect on pituitary function since it factors both cyst and gland volume. Large cysts should be monitored closely, given their extreme, erratic behavior.

Placement of Ommaya Reservoirs Using Electromagnetic Neuronavigation and Neuroendoscopy: A Retrospective Study with Cost-Benefit Analysis.

BACKGROUND: Placement of intraventricular catheters in oncology patients is associated with high complication rates. Placing Ommaya reservoirs with the zero-error precision protocol (ZEPP), a combination of neuronavigation (AxiEM stereotactic navigation) and direct verification of catheter tip placement with a flexible neuroendoscope, is associated with decreased complication rates as a result of increased catheter placement accuracy. However, the ZEPP costs more than traditional methods of catheter placement, and the question of whether this increased accuracy with the ZEPP is cost-effective is unknown. METHODS: We performed a single-center retrospective chart review of 50 consecutive ommaya reservoir patient placements between 2010 and 2017. Twenty-five ventricular catheters were placed using the ZEPP protocol, and 25 ventricular catheters were placed using only AxiEM stealth navigation. Postoperative catheter accuracy and complication rates were assessed. A cost-benefit analysis was then conducted to determine if the overall cost for placing Ommaya reservoirs with the ZEPP was effective compared with the alternative method of using neuronavigation alone. RESULTS: In the non-ZEPP cohort, 10 of 25 catheters were placed within the optimal location compared with 25 of 25 catheters placed in the ZEPP cohort. Three complications occurred in the non-ZEPP cohort: 2 malpositioned catheters required surgical revision and 1 catheter-related hemorrhage resulted in a prolonged stay in the intensive care unit. No complications occurred in the ZEPP cohort. A cost-benefit analysis showed $4784 savings per patient with ZEPP utilization because of the high complication-associated costs. CONCLUSIONS: Implementation of the ZEPP for verifying ventricular catheter placement in Ommaya reservoirs improved catheter tip accuracy, resulted in lower complication rates, and was more cost-effective when compared with the non-ZEPP cohort, which used only neuronavigation. The ZEPP can be used for ventricular shunt catheter placement to decrease complications and verify catheter tip accuracy in Ommaya or standard ventriculoperitoneal shunts.

The prevalence and volumetry of pituitary cysts in children with growth hormone deficiency and idiopathic short stature.

Background Pituitary cysts have been speculated to cause endocrinopathies. We sought to describe the prevalence and volumetry of pituitary cysts in patients with growth hormone deficiency (GHD) and idiopathic short stature (ISS). Methods Six hundred and eighteen children evaluated for growth failure at the Division of Pediatric Endocrinology at New York Medical College between the years 2002 and 2012, who underwent GH stimulation testing and had a brain magnetic resonance imaging (MRI) prior to initiating GH treatment were randomly selected to be a part of this study. High resolution MRI was used to evaluate the pituitary gland for size and the presence of a cyst. Cyst prevalence, cyst volume and percentage of the gland occupied by the cyst (POGO) were documented. Results Fifty-six patients had a cyst, giving an overall prevalence of 9.1%. The prevalence of cysts in GHD patients compared to ISS patients was not significant (13.5% vs. 5.7%, p=0.46). Mean cyst volume was greater in GHD patients than ISS patients (62.0 mm3 vs. 29.4 mm3, p=0.01). POGO for GHD patients was significantly greater (p=0.003) than for ISS patients (15.3%±12.8 vs. 7.1%±8.0). Observers were blinded to patient groups. Conclusions GHD patients had a significantly greater volume and POGO compared to ISS patients. This raises the question of whether cysts are implicated in the pathology of growth failure.

Magnetic resonance imaging of idiopathic herniation of the cuneus gyrus.

A 65-year-old woman presenting with chronic headaches and without overt visual symptomatology was found to have herniation of the cuneus gyrus into the superior cerebellar cistern. Only one prior case of idiopathic brain herniation has been described, in which the parahippocampal gyrus herniated into the ambient cistern. In that case a biopsy was performed as the herniation was mistaken for a tumor. We describe the features of idiopathic brain herniation that would mitigate the necessity for undergoing brain biopsy.

Basilar Artery Herniation into the Sphenoid Sinus Secondary to Traumatic Skull Base Fractures: Case Report and Review of the Literature.

BACKGROUND: Traumatic clival fractures occur with less than 0.6% frequency and can be associated with significant neurovascular injuries. The most serious of these injuries is to the basilar artery in which the artery is dissected or is fully occluded, resulting in infarction of the brainstem and cerebellum. Among early reports of these injuries, postmortem autopsy showed entrapment, or incarceration, of the basilar artery at the clival fracture site. A literature search revealed 11 cases of entrapment of the basilar artery within a clival fracture. CASE DESCRIPTION: This report describes a 59-year-old man after a motor vehicle crash with computed tomography showing a basilar artery herniation through a sphenoid sinus fracture. The patient subsequently developed brainstem and cerebellar infarcts. CONCLUSIONS: Basilar artery incarceration and herniation through the sphenoid sinus is rare. Such an injury portends a poor prognosis. We discuss the relevant clinical imaging and review the literature.

Pituitary volume in children with growth hormone deficiency, idiopathic short stature and controls.

BACKGROUND: The objective of the study was to describe the pituitary volume (PV) in pediatric patients with isolated growth hormone deficiency (IGHD), idiopathic short stature (ISS) and normal controls. METHODS: Sixty-nine patients (57 male, 12 female), with a mean age of 11.9 (±2.0), were determined to have IGHD. ISS was identified in 29 patients (20 male, 9 female), with a mean age of 12.7 (±3.7). Sixty-six controls (28 female, 38 male), mean age 9.8 (±4.7) were also included. Three-dimensional (3D) magnetic resonance images with contrast were obtained to accurately measure PV. RESULTS: There was a significant difference in the mean PV among the three groups. The IGHD patients had a mean PV 230.8 (±89.6), for ISS patients it was 286.8 (±108.2) and for controls it was 343.7 (±145.9) (p<0.001). There was a normal increase in PV with age in the ISS patients and controls, but a minimal increase in the IGHD patients. CONCLUSIONS: Those patients with isolated GHD have the greatest reduction in PV compared to controls and the patients with ISS fall in between. We speculate that a possible cause for the slowed growth in some ISS patients might be related to diminished chronic secretion of growth hormone over time, albeit having adequate pituitary reserves to respond acutely to GH stimulation. Thus, what was called neurosecretory GHD in the past, might, in some patients, be relative pituitary hypoplasia and resultant diminished growth hormone secretion. Thus, PV determinations by magnetic resonance imaging (MRI) could assist in the diagnostic evaluation of the slowly growing child.

A Novel Approach Using Electromagnetic Neuronavigation and a Flexible Neuroendoscope for Placement of Ommaya Reservoirs.

OBJECTIVE: Placement of intraventricular catheters in oncology patients can be associated with morbidity given their small to slit-like ventricles and underlying hematologic disorders. We studied the accuracy of placing Ommaya reservoirs using neuronavigation and a flexible neuroendoscope to verify catheter positioning. METHODS: Ommaya reservoirs placed in 25 oncology patients between 2013 and 2015 were retrospectively reviewed. Twenty-five ventricular catheters were placed using the AxiEM stealth frameless neuronavigation system and a flexible neuroendoscope. Postoperative catheter accuracy, operative complications, and postoperative complications were assessed. We discuss surgical protocol and technical nuances. RESULTS: All ventricular catheters were successfully placed into the ipsilateral (84%) or contralateral (16%) foramen of Monro. A single ventricular catheter pass was needed to cannulate the ventricle in 96% of patients. The mean accuracy was 4.09 ± 3.47 mm from the target, the ipsilateral foramen of Monro. One patient had a catheter tract hemorrhage seen on postoperative imaging related to thrombocytopenia. No postoperative neurologic deficits were seen. CONCLUSIONS: A combined neuronavigation and neuroendoscopic approach improved catheter tip accuracy compared with accuracy rates described in the literature using other techniques. This approach can be adapted toward routine clinical practice of placing ventricular shunt catheters and Ommaya reservoirs.

Neurotoxicity of intrathecal methotrexate: MR imaging findings.

We report a case of intrathecal methotrexate neurotoxicity manifesting as left arm weakness and aphasia. Diagnostic imaging showed restricted diffusion and fluid-attenuated inversion recovery imaging findings were normal at presentation. Three weeks later, diffusion abnormalities resolved, and T2-weighted studies showed increased signal intensity of prolonged T2 changes in areas of prior restricted diffusion. We attribute the clinical and radiographic findings to cytotoxic edema secondary to intrathecal methotrexate.

Efficacy of multiple intraarterial papaverine infusions for improvement in cerebral circulation time in patients with recurrent cerebral vasospasm.

OBJECT: Cerebral vasospasm that is caused by aneurysmal subarachnoid hemorrhage and that is refractory to maximal medical management can be treated with selective intraarterial papaverine infusions. The effects of single papaverine treatments on cerebral circulation time are well known. The purpose of this study was to assess the efficacy of multiple, repeated papaverine infusions on the cerebral circulation time in patients with recurrent vasospasm. METHODS: A retrospective study was conducted in 17 patients who received multiple intraarterial papaverine infusions in 91 carotid artery (CA) territories for the treatment of cerebral vasospasm. Cerebral circulation times were measured from the first angiographic image, in which peak contrast was seen above the supraclinoid internal CA, to the peak filling of cortical veins. Glasgow Outcome Scale (GOS) scores assessed 12 months after discharge were reviewed. Cerebral circulation times in 16 CA territories were measured in a control group of 11 patients. Seventeen patients received a total of 91 papaverine treatments. Prolonged cerebral circulation times improved after 90 (99%) of 91 papaverine treatments. The prepapaverine mean cerebral circulation time was 6.54 seconds (range 3.35-27 seconds) and the immediate postpapaverine mean cerebral circulation time was 4.19 seconds (range 2.1-12.6 seconds), an overall mean decrease of 2.35 seconds (36%, p < 0.001). Recurrent vasospasm reflected by prolonged cerebral circulation times continued to improve with subsequent papaverine infusions. Repeated infusions were just as successful quantitatively as the primary treatment (mean change 2.06 seconds). The mean cerebral circulation time in the control group was 5.21 seconds (range 4-6.8 seconds). In five patients a dramatic reversal of low-attenuation changes was detected on computerized tomography scans. The mean GOS score at 12 months after discharge was 3.4. CONCLUSIONS: The preliminary results indicate that multiple intraarterial papaverine treatments consistently improve cerebral circulation times, even with repeated infusions in cases of recurrent vasospasm.

Traumatic arteriovenous fistula of the posterior inferior cerebellar artery treated with endovascular coil embolization: case report.

BACKGROUND: High-flow intracranial arteriovenous (AV) fistulas associated with giant varices are rare lesions. These varices can present with symptoms from mass effect, spontaneous hemorrhage, and seizures to cardiac failure. Direct AV fistulas of the posterior inferior cerebellar artery (PICA) are extremely rare lesions, with only two cases reported in the literature. CASE DESCRIPTION: The authors present an unusual case of a 25-year-old male with a direct AV fistula of the PICA that resulted from a fracture of the occipital condyle. This high-flow AV fistula drained into a giant varix of the vein of the lateral recess that compressed the brainstem, resulting in a Wallenberg syndrome. The patient underwent embolization of the proximal PICA feeding the fistula with a Guglielmi detachable coil (GDC), which resulted in thrombosis of the varix. A postembolization angiogram showed occlusion of the PICA AV fistula and draining varix. A computed tomography (CT) scan performed at a 10-month follow-up visit showed dramatic decompression of the brainstem. Although the patient continued to have some sensory changes secondary to Wallenberg syndrome, he was otherwise doing well neurologically. CONCLUSION: The treatment of this lesion is difficult because of its location near the brainstem. Postocclusion edema or hemorrhage can result in mass effect and life-threatening brainstem compression. Our patient, whose AV fistula was caused by trauma, was treated effectively with GDC embolization.

Intracranial hypotension syndrome: a comprehensive review.

Intracranial hypotension may have variable clinical presentations, but has a rather uniform component of postural headache among its symptomatology. Its symptoms are explainable given the effects of the hypotension and attempts within the craniospinal axis to maintain volume homeostasis in the face of cerebrospinal fluid leakage (Monro-Kellie hypothesis). The imaging corollaries of the consequences of intracranial hypotension are especially well depicted on magnetic resonance imaging studies.

Aspergillus osteomyelitis of the lumbar spine complicated with orbital apex syndrome: A potential role of the Batson's plexus in disease propagation.

We report a rare case of orbital apex syndrome following epidural steroid injections of the lumbar spine in an immunocompetent individual with osteomyelitis and discitis caused by Aspergillus fumigatus. We suspect that the craniospinal venous system, also known as the Batson's plexus, was the main route for steroid-facilitated disease propagation from the spine to intracranial structures.

Three cases of benign giant cell tumor with unusual imaging features.

OBJECTIVE: Imaging findings for giant cell tumors (GCT) of the spine displaying aggressive characteristics have not been widely reported. MATERIALS AND METHODS: Patients with biopsy-proven GCT were included in the study. Three cases fulfilled these criteria. RESULTS: MRI and CT demonstrated disc space involvement and vertebral body compression. CONCLUSION: Acute fracture, subluxation, and extension through the disc space have not been previously described and, while atypical for benign lesions, may in fact be typical for GCT of the spine.

Growing burr hole: enlarging pseudomeningocele at the site of a craniostomy.

BACKGROUND: Growing skull fractures and other enlarging skull defects are rare postoperative occurrences. We report here on a 10-month-old girl who presented with an enlarging burr hole and pseudomeningocele after an endoscopic third ventriculocisternostomy. METHODS: Evaluation of an enlarging subcutaneous mass at the site of the burr hole included computed tomography scans and magnetic resonance imaging, which revealed a pseudomeningocele. The patient underwent repair of the lesion, including dural closure and cranioplasty. CONCLUSIONS: Growing skull fractures or other enlarging bone defects may occur after burr hole placement, particularly in infants who require larger access sites for endoscopy.

Vertebral artery dissection in children: a comprehensive review.

Vertebral artery dissection (VAD) has been infrequently recognized in children. The authors have reviewed 68 reported cases of VAD in children in the existing literature. An association between routine types of neck movement in sports and the evolution of VAD was recognized in half of the reported cases. Boys outnumbered girls by a ratio of 6.6 to 1, in contrast to adults, for whom the male to female ratio is approximately equal (1.3 to 1). Neck pain, one of the hallmark symptoms of VAD in adults, was infrequently noted in this young population (12%). Most children presented with various combinations of symptoms and signs, including ataxia (53%), headache (38%) and vomiting (34%). Eye signs or symptoms were noted in 72% of patients, and paresis/paralysis of one or more extremity occurred in 54%. Angiography was the method most frequently used to diagnose VAD (63/68; 93%). Magnetic resonance angiography (MRA) revealed pathognomonic signs of VAD in only 3 out of 13 patients evaluated (23%). In this series of 68 patients, 48 reports failed to indicate whether or not a cervical X-ray was performed, but in the 20 patients for whom such information was recorded, half had skeletal abnormalities in the occipital/atlas/axis region. The most common treatments were antiplatelet therapy (n = 15) and anticoagulation with (n = 8) or without (n = 7) supplemental antiplatelet therapy. Asymptomatic recovery occurred in 12 of the 15 patients (80%) who received antiplatelet therapy compared with 4 of the 15 patients (27%) who received anticoagulation therapy with or without antiplatelet therapy. There is a very high incidence of associated cervical anomalies in children with VAD. Further studies are required to determine if noninvasive examinations such as magnetic resonance imaging, ultrasonography, computed tomography angiography and MRA could replace angiography as the modality of choice in establishing the diagnosis of VAD in children. The role of different therapies for children presenting with symptoms related to VAD is unclear.