Craniocervical Junction Meningiomas without Hydrocephalus Presenting Solely with Syncope: Report of 2 Cases.

OBJECTIVE: To our knowledge, there have not been any reported cases of a meningioma of the craniocervical region presenting solely with syncope as its initial symptom. Only 1 case of meningioma presenting with syncope has been published, but it was associated with hydrocephalus. We report 2 cases of syncope caused by a craniocervical junction meningioma, with syncope being the sole presenting symptom and without hydrocephalus. We discuss the possible pathophysiology, as well as the clinical relevance of this type of presentation. METHODS: We reviewed the charts, operative details, and imagery of 2 cases of meningioma in the region of the craniocervical junction, with syncope as their sole presenting feature. We also reviewed the literature. RESULTS: In 1 case the syncope occurred spontaneously. In the other, it occurred during a Valsalva maneuver. Both meningiomas were surgically removed via a retromastoid approach. There was no recurrence of syncope following surgery. Following a literature review, we found 1 case of posterior fossa meningioma presenting with syncope, but hydrocephalus was also present. CONCLUSION: Syncope can be the sole manifestation of a meningioma of the craniocervical junction. Such syncopes are a consequence of transient dysfunction of the autonomous pathways in the medulla and/or of the medulla's output. In the absence of other causes of syncope, a meningioma in this region, even in the absence of hydrocephalus, should not be considered as fortuitous, but rather as the actual cause of syncope. Recognizing this possibility offers the potential for proper diagnosis and appropriate treatment of the syncope.

Maternal administration of meclozine for the treatment of foramen magnum stenosis in transgenic mice with achondroplasia.

OBJECTIVE Achondroplasia (ACH) is the most common short-limbed skeletal dysplasia caused by gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Foramen magnum stenosis (FMS) is one of the serious neurological complications in ACH. Through comprehensive drug screening, the authors identified that meclozine, an over-the-counter drug for motion sickness, inhibited activation of FGFR3 signaling. Oral administration of meclozine to the growing ACH mice promoted longitudinal bone growth, but it did not prevent FMS. In the current study, the authors evaluated the effects of maternal administration of meclozine on FMS in ACH mice. METHODS The area of the foramen magnum was measured in 17-day-old Fgfr3ach mice and wild-type mice using micro-CT scanning. Meclozine was administered to the pregnant mice carrying Fgfr3ach offspring from embryonic Day (ED) 14.5 to postnatal Day (PD) 4.5. Spheno-occipital and anterior intraoccipital synchondroses were histologically examined, and the bony bridges were scored on PD 4.5. In wild-type mice, tissue concentrations of meclozine in ED 17.5 fetuses and PD 6.5 pups were investigated. RESULTS The area of the foramen magnum was significantly smaller in 17-day-old Fgfr3ach mice than in wild-type mice (p < 0.005). There were no bony bridges in the spheno-occipital and anterior intraoccipital synchondroses in wild-type mice, while some of the synchondroses prematurely closed in untreated Fgfr3ach mice at PD 4.5. The average bony bridge score in the cranial base was 7.053 ± 1.393 in untreated Fgfr3ach mice and 6.125 ± 2.029 in meclozine-treated Fgfr3ach mice. The scores were not statistically significant between mice with and those without meclozine treatment (p = 0.12). The average tissue concentration of meclozine was significantly higher (508.88 ± 205.16 ng/g) in PD 6.5 mice than in ED 17.5 mice (56.91 ± 20.05 ng/g) (p < 0.005). CONCLUSIONS Maternal administration of meclozine postponed premature closure of synchondroses in some Fgfr3ach mice, but the effect on preventing bony bridge formation was not significant, probably due to low placental transmission of the drug. Meclozine is likely to exhibit a marginal effect on premature closure of synchondroses at the cranial base in ACH.

Inadvertent disk injection during transforaminal epidural steroid injection: steps for prevention and management.

OBJECTIVES: To report two cases of disk injection during transforaminal epidural steroid injection, and to discuss ways to prevent and manage this under-appreciated complication. DESIGN: Case reports and literature reviews. PATIENTS: Two patients with radicular symptoms underwent transforaminal epidural steroid injections under fluoroscopic guidance. The needle in both cases was placed in the center of the intervertebral foramen, about 1 cm above the inferior endplate. Injection of contrast in both cases revealed diskographic spread. Repeat magnetic resonance imaging revealed a large foraminal disk herniation in both patients. RESULTS: A literature search identified three studies whereby the use of a single-needle technique to perform diskography was clearly noted in conjunction with the number of infectious complications. Comparing these data with the incidence of diskitis when a double-needle approach was used found the infectious risk to be considerably higher. There are no data regarding whether imaging studies affect outcomes following epidural steroid injections. CONCLUSIONS: These cases and similar complications following transforaminal epidural steroid injections provide anecdotal evidence that recent imaging studies, repeated not only for qualitatively new symptoms but after a sustained quantitative increase in pain, may reduce the complication risk. Data extrapolated from studies on diskitis suggest that administering parenteral, and possibly also intradiskal antibiotics, immediately after inadvertent disk injection is appreciated, may reduce the infectious risk.

Expression of neuropeptides and growth-associated protein 43 (GAP-43) in cutaneous and mucosal nerve structures of the adult rat lower lip after mental nerve section.

The reinnervation of the adult rat lower lip has been investigated after unilateral section of the mental nerve. Rats were sacrificed at 4, 7, 9, 14, 30, and 90 days after the operation. A further group of animals with section of the mental nerve and block of the alveolar nerve regeneration, was sacrificed at 14 days. Specimens were processed for immunocytochemistry with antibodies against PGP 9.5, GAP-43 or neuropeptides (CGRP, SP and VIP). Four days after nerve section, axonal degeneration seems evident in the mental nerve branches and inside skin and mucosa. GAP-43 immunoreactivity is intense in the mental nerve 7 days after nerve section and it reaches its maximal expression and distribution in peripheral nerve fibres at 14 days. At 30 days, the decline in its expression is associated with the increase of PGP9.5-, SP-, and CGRP immunopositivity. VIP is observed only in perivascular fibres at all times observed. Present results suggest that, after sensory denervation of the rat lip, nerve fibres in skin and mucosa remain at lower density than normal. The different time courses in the expression of neuropeptides and GAP-43 suggest a possible early involvement of GAP-43 in peripheral nerve regeneration.

Induced leukemia and antineoplastic agent carmustine cause permanent changes in craniofacial growth of immature rats.

OBJECTIVES: The purpose of the present study was to investigate the possible effects of untreated terminal leukemia on craniofacial growth (Study I), and also the effects of the antineoplastic agent carmustine on craniofacial growth in both leukemic and healthy rats (Study II). MATERIAL: A total of 367 inbred Piebald variegated rats was used. METHOD: Transmission of leukemic cells was carried out intraperitoneally at 30 days of age, and without treatment (Study I), the rats reached the terminal phase within 17 +/- 1 days. Rats with induced leukemia was cured with 10 mg/kg carmustine (BCNU) given on days 6 and 13 following cell transmission (Study II), the rats remaining in remission until they were killed at 100 days of age. Final weight was recorded and 12 craniofacial dimensions and tibial length were measured with a digital sliding caliper. RESULTS: The results showed that the effect of untreated terminal rat leukemia (Study I) on craniofacial growth differed between the genders. Male rats showed clearly reduced dimensions of facial structures and also retarded general body growth, whereas females showed differences mainly in general body growth. The effect of cured leukemia (Study II) as such was minor, while BCNU had a strong and permanent reducing effect on both craniofacial and general body growth in both genders. CONCLUSION: We suggest that the results in Study I came both from a direct effect of leukemia and an indirect effect of untreated terminal leukemia through malnutrition. The alkylating agent BCNU seemed to be the main cause of permanent craniofacial and general growth retardation in Study II.

Growth hormone therapy in achondroplasia.

The status of growth hormone (GH) secretion together with the effect of GH therapy was studied in six children with achondroplasia. One patient had impaired GH secretion, which may, in part, be due to obesity. The pre-GH-treatment height velocity was 3.8 +/- 0.7 cm/year, but this increased to 6.0 +/- 1.0 cm/year in the first year of treatment and to 4.4 +/- 0.6 cm/year in the second year. One patient who underwent GH therapy for 4 years showed good response in height velocity. A considerable variation was observed in response to GH therapy within the treated cases.