Vitamine B12 deficiency in children: a diagnostic challenge.

Cobalamin or vitamin B12 (vitB12) is involved in DNA synthesis, haematopoiesis and myelinisation. Consequently, vitB12 deficiency causes various symptoms, such as megaloblastic anaemia, neurologic signs or pancytopenia. Despite possible severe symptoms, vitB12 deficiency can present asymptomatically. We report six paediatric patients with different aetiologies of vitB12 deficiency ranging from a subtle to a more overt presentation. VitB12 deficiency is a diagnostic challenge due to the lack of consensus on normal values of vitB12 and its co-markers (folate, holotranscobalamin, methylmalonic acid, homocysteine) and the lack in specificity and sensitivity of the serum vitB12 analysis. All cases were treated with parenteral vitB12. Last decades, evidence supporting high dose oral treatment being as effective as the intramuscular (IM) therapy, also in children, is growing.

Broader head, stronger bite: In vivo bite forces in European eel Anguilla anguilla.

This work examined three different phenotypes of the yellow-eel stage of the European eel Anguilla anguilla, broad-heads, narrow-heads and eels with an intermediate head shape. The aim was to see whether broad-headed A. anguilla, which generally consume harder, larger prey, such as crustaceans and fish, exerted greater bite force than the narrow-headed variant, which mainly consume soft, small prey such as chironomid larvae. It was found that in 99 yellow A. anguilla, in vivo bite force of broad-heads are higher compared with narrow-heads and intermediates.

Ontogenesis of opercular deformities in gilthead sea bream Sparus aurata: a histological description.

The aim of this study was to characterize histological changes during opercular osteogenesis in farmed gilthead sea bream Sparus aurata larvae from 7 to 69 days post hatching (dph) and compare normal osteogenesis with that of deformed opercles. Mild opercular deformities were first detected in 19 dph larvae by folding of the opercle's distal edge into the gill chamber. Here, the variation in the phenotype and the irregular bone structure at the curled part of the opercles is described and compared with the histology of normal opercles. Results indicated that deformed opercles still undergo bone growth with the addition of new matrix by osteoblasts at the opercular surface, especially at its edges. No significant difference was found in bone thickness between deformed and normal opercles. In addition to differences in bone architecture, differences in collagen fibre thickness between normal and deformed opercles were also found.

Grasping convergent evolution in syngnathids: a unique tale of tails.

Seahorses and pipehorses both possess a prehensile tail, a unique characteristic among teleost fishes, allowing them to grasp and hold onto substrates such as sea grasses. Although studies have focused on tail grasping, the pattern of evolutionary transformations that made this possible is poorly understood. Recent phylogenetic studies show that the prehensile tail evolved independently in different syngnathid lineages, including seahorses, Haliichthys taeniophorus and several types of so-called pipehorses. This study explores the pattern that characterizes this convergent evolution towards a prehensile tail, by comparing the caudal musculoskeletal organization, as well as passive bending capacities in pipefish (representing the ancestral state), pipehorse, seahorse and H. taeniophorus. To study the complex musculoskeletal morphology, histological sectioning, µCT-scanning and phase contrast synchrotron scanning were combined with virtual 3D-reconstructions. Results suggest that the independent evolution towards tail grasping in syngnathids reflects at least two quite different strategies in which the ancestral condition of a heavy plated and rigid system became modified into a highly flexible one. Intermediate skeletal morphologies (between the ancestral condition and seahorses) could be found in the pygmy pipehorses and H. taeniophorus, which are phylogenetically closely affiliated with seahorses. This study suggests that the characteristic parallel myoseptal organization as already described in seahorse (compared with a conical organization in pipefish and pipehorse) may not be a necessity for grasping, but represents an apomorphy for seahorses, as this pattern is not found in other syngnathid species possessing a prehensile tail. One could suggest that the functionality of grasping evolved before the specialized, parallel myoseptal organization seen in seahorses. However, as the grasping system in pipehorses is a totally different one, this cannot be concluded from this study.

Musculoskeletal structure of the feeding system and implications of snout elongation in Hippocampus reidi and Dunckerocampus dactyliophorus.

A thorough morphological description of the feeding apparatus in Hippocampus reidi, a long-snouted seahorse, and Dunckerocampus dactyliophorus, an extremely long-snouted pipefish, revealed specialized features that might be associated with the fast and powerful suction feeding, like the two ligamentous connections between the lower jaw and the hyoid, the saddle joint of the latter with the suspensorium and the vertebro-pectoral fusion that articulates on three points with the cranium. Despite the conserved morphology of the feeding apparatus, it was found that in H. reidi the orientation of the occipital joint is ventrocaudal, the sternohyoideus and epaxial muscles are more bulky and both have a short tendon. In D. dactyliophorus, on the other hand, the protractor hyoidei muscle is enclosed by the mandibulo-hyoid ligament, the sternohyoideus and epaxial tendons are long and a sesamoid bone is present in the latter. These features were compared to other syngnathid species with different snout lengths to evaluate the implications of snout elongation on the musculoskeletal structure of the cranium. The arched path of the adductor mandibulae and the greater rigidity of the lower jaw might be related to elongation of the snout, as it yields an increased mechanical advantage of the lower jaw system and a reduced torque between the elements of the lower jaw during protractor hyoidei muscle contraction, respectively. Nevertheless, most observed features did not seem to be related to snout length, but might be associated with different force-generating strategies.

[Clinical aspects and treatment of dural-spinal arteriovenous fistulas with perimedullary venous drainage. 10 cases]. / Aspects cliniques et traitement des fistules artério-veineuses durales rachidiennes à drainage veineux périmédullaire. A propos de 10 observations.

BACKGROUND AND PURPOSE: Spinal dural arteriovenous fistulas (SDAVF) are rare but represent the most frequent spinal arteriovenous malformation. Their clinical manifestations are well known, but their management can still be discussed between surgery and endovascular treatment. The purpose of this study is to emphasize the pre-eminence of surgical management for posterior and postero-lateral fistulas, which are the most common location of the malformation. METHODS: We report a consecutive series of 10 patients with SDAVF treated between July, 1995 and July, 1997. Results are compared with other series of the literature. RESULTS: Clinical manifestations were not specific and the diagnosis was established in most cases only one year after the onset of symptoms, as a progressive myelopathy. Low back pain was present in 4 patients, with pseudo-radicular pain in the lower limbs suggesting spinal degenerative disease in 3 cases. At the time of diagnosis, 8 patients had permanent motor weakness of the lower limbs, usually associated with hypesthesia and sphincterial dysfunction (7 cases). In all cases, the diagnosis was established using MRI. In most cases, the intradural draining spinal veins were also visible on MRI images. The location of the SDAVF was always precised by angiography, and was located between T5 and L1 in our series. Seven patients were successfully operated on, with surgical interruption of the intradural draining vein. Three patients underwent an endovascular treatment, but two of them were operated on later, as control angiography showed recurrence of the SDAVF. The clinical status of patients always improved after treatment, but recovery was incomplete in patients with severe and long lasting neurological deficit. CONCLUSIONS: Surgical interruption of the intradural draining vein is a safe and effective method of treatment of SDAVF, especially for posterior and postero-lateral fistulas. Endovascular treatment is recommended for anterior locations of SDAVF.

[Combination treatment for pilocytic astrocytoma: stereotaxic radiosurgery and endocavitary radiotherapy]. / Traitement combiné d'un astrocytome pilocytique: radiochirurgie stéréotaxique et radiothérapie endocavitaire.

The treatment of a pilocytic astrocytoma located in a functional area can be performed using radiosurgery. We report a 7 year old male, right-handed, who presented with a pilocytic astrocytoma in the left parieto-occipital lobe. After a 7 year follow-up, the tumor became symptomatic (partial and generalized seizures). The CT scan and nuclear magnetic resonance imaging revealed an increased size of the mural tumor and the development of a cystic component. Multi-beam irradiation of the tumor (dose of 30 Gy at the center with 21 Gy on the isodose 70%) was performed with a LINAC for radiosurgery coupling a modified Saturne 18 MeV linear accelerator and a Talairach stereotactic frame. Following multi-beam irradiation, the increase in size of the cyst imposed further intracavitary radiation using Rhenium 186 (186Re) to deliver 400 Gy to the cyst wall. After a period of intense cerebral edema, resolutive with steroid treatment, we obtained progressive cyst disappearance and mural nodule retraction. A PET scan, performed 3 years after this treatment, revealed no metabolic activity in the persistent mural nodule. The patient remains totally asymptomatic.

[Acquired lesions of the corpus callosum]. / Lésions acquises du corps calleux.

Acquired lesions of the corpus callosum may be related to tumoral, vascular, traumatic or degenerative disorders and, one must not forget, can result from surgical access. Currently, the quality of neuroimaging enables a validation or precision of anatomoclinical, neuropsychological and neurophysiological correlations established from experimental and/or autopsy data. However the "specific" signs of acquired lesions of the corpus callosum are often quite complex and may be readily overlooked or masked within a heterogeneous clinical presentation due to more or less important associated lesions of neighboring structures. Therapeutic management (tumors, arteriovenous malformations, cavernomas) depend on the nature and the extent of the lesion more than the functional nature of this inter-hemispheric commissure with an exceptional functional plasticity, particularly when the lesion is limited.

Strategy of craniofacial reconstruction after resection of spheno-orbital "en plaque" meningiomas.

Surgical resection of spheno-orbital "en plaque" meningiomas should be as complete as possible to prevent tumor recurrence and therefore requires a bone reconstruction. We report a series of 20 patients operated on for spheno-orbital "en plaque" meningioma between 1981 and 1993. The surgical treatment included a resection of the involved dura and a wide resection of tumoral bone using a fronto-temporal craniotomy extended to the orbitozygomaticomalar bone ridge. The craniofacial reconstruction was performed in the same operative procedure using iliac bone autograft in 11 patients, internal cortical bone from the bone flap in 8 patients, and a coral graft in 1 patient. The cosmetic result was scored according to the following criteria: superior frontal paralysis, appearance of the orbitomalar bone ridge, shape of the external temporal fossa, and projection of the eyeballs. The cosmetic result was scored as excellent or good in 17 patients, average in 2 patients, and poor in 1 patient. The iliac bone autograft appeared to be the best material for craniofacial reconstruction because it could be modeled easily to the desired shape. However, the reconstruction technique was modified as necessary according to the extent of tumor removal, clinical presentation, and age of the patient.

[Results of hearing preservation in surgery of vestibular schwannoma. Value of combined retrosigmoid and middle fossa approaches]. / Résultats de la conservation de l'audition dans la chirurgie du schwannome vestibulaire. Intérêt de la voie combinée sus-pétreuse et rétrosigmoïde.

We report our experience of hearing preservation in acoustic neurinoma surgery, using combined retrosigmoid and middle fossa approaches. Fifty neurinomas operated on between 1987 and 1994 were included in this retrospective study. Hearing preservation surgery was performed for patients with grade II or grade III tumors (mean average tumor diameter: 14.4 mm), presenting with normal or serviceable pre-operative hearing (pure tonal average decrease less than 50 dB, speech discrimination score better than 50%). Isolated middle fossa approach was used in 3 cases, isolated retrosigmoid approach in 2 cases. The 45 other cases were operated on using both routes during the same procedure. Total removal of the tumor with anatomic facial preservation was performed in all cases. No death occurred. The facial function assessed 3 months after surgery was good in 84% of cases (House-Brackmann grades I or II). The mean follow-up was 42 months. Post-operative hearing was measurable in 48% of cases and serviceable in 30% of cases. The size of the tumor and the level of preoperative hearing appear to be the most important predictive criteria for successful hearing preservation.

[Sacral nerve root cysts. Discussion on the mechanism of nerve root suffering. Apropos of 4 cases]. / Kystes périradiculaires sacrés. Discussion du mécanisme de souffrance radiculaire. A propos de quatre observations.

Low back pain, sciatia or perineal chronic pain are sometimes related to perineural sacral cysts. Surgical treatment is difficult and may lead to pain or neurological worsening. We report four cases of symptomatic perineural cysts; three of them where operated on with two good results and one increasing perineal pain. Anatomical and radiological description are reviewed. From a therapeutical point of view, we can distinguish two clinical types of radicular suffering. Perineural cyst can cause a commun radicular extrinsic compression; in such a case surgical operation will improve radicular pain. The cystic nerve root can present an intrinsic suffering because of on intradural dilaceration. Then surgery must be avoided specially when many roots are involved because it may worsen the pluriradicular suffering.

[Value of peroperative endoscopy in treating giant lumbosacral meningocele]. / Intérêt de l'endoscopie per-opératoire dans le traitement d'une méningocèle géante lombo-sacrée.

Lombosacral meningocele may be responsible for sciatica, low backache, cauda equina syndrome according to their localization and size. When they are symptomatic, the surgical purpose is to close the communication between the meningeal sac and the cyst. For giant meningocele, acute localization of the communication may be difficult. In such cases, peroperative endoscopy may be useful. We present a case of sciatica related to a giant meningocele extended from L2 to S2. MRI, CT scan and myelography were unable to localize the communication. We used peroperative endoscopy for direct visualization of the communication in order to minimize the surgical approach. An intrathecal nerve root was found strangulated in the communication suggesting an original kind of nerve root suffering. The communication was only closed. The patient made an uneventful recovery with complete relief of symptoms. Magnetic resonance imaging 3 months later showed a significant decrease of the meningocele without any further radicular compression.

Cervical myelopathy secondary to Hunter syndrome in an adult.

We present a case of type II mucopolysaccharidosis in which the diagnosis was delayed until the onset of cervical myelopathy in adulthood. Radiographic features were characteristic, with striking dural thickening shown on CT and MR imaging.

Intradural epidermoid cysts of the cerebellopontine angle: diagnosis and surgery.

We report on our recent experience with epidermoid cysts in the cerebellopontine angle. We operated on nine patients since 1985, seven of which were investigated with magnetic resonance imaging. Since the arrival of modern neuroimaging, large lesions can be found with only discrete symptoms, such as isolated tinnitus or unspecific headache. With computed tomography and magnetic resonance imaging, preoperative diagnosis was achieved for most patients; sometimes, however, epidermoid cysts may be very similar to arachnoid cysts. Surgery is the only possible treatment. The decision to operate should be carefully discussed for each patient, particularly if the patient is asymptomatic. The extent of the lesion at the anterior aspect of the brain stem, and sometimes above the tentorium cerebelli, fragile cortex, and vessels, and hazards of postoperative chemical meningitis often make such surgery difficult. The surgeon should not attempt total removal of the cyst membrane. Most patients who undergo surgery, however, recover well, with no or few sequelae. With a mean 3-year follow-up, no recurrence occurred, despite partial removal, as a result of the peculiarly slow growth of these lesions.

Carcinomatous meningitis in a case of anaplastic meningioma.

Malignant meningiomas are associated with a high rate of local recurrence, but seldom give remote metastases. Here, we report a case with carcinomatous meningitis occurring 13 months after treatment of the initial tumor. MRI showed no significant abnormalities. CSF contained abnormal cells, and electronic microscopy after cytocentrifugation confirmed their identity with the initial tumor.

[Cranio-cerebral dermoid and epidermoid cysts. Classification and pathogenesis]. / Les kystes dermoïdes et épidermoïdes crânio-encéphaliques. Classification et pathogénie.

The pathogenesis of cranial dermoids and epidermoids is still controversial, owing to the multiple etiologies and locations of these lesions. We reviewed 25 cases, classified as follows: extradural lesion of the calvarium; of the occipital squama; dysraphic occipital lesions; and strictly intradural lesions. In the latter group, all lesions but one were in a paramedian, prenevraxial situation, and could be classified according to their situation relative to the tentorium cerebelli. In our series, strictly intradural dermoids are more often in a rostral situation, and epidermoids in a more caudal situation. Dermoids appear earlier in life than epidermoids, suggesting a more rapid growth due to eccrine secretion. For each group of lesions, the pathogenic hypotheses are studied. Inclusion of epidermal nests at different levels might result from traumatism, dysraphism, or developmental trouble in the lamination of the different layers of the meninges. Most intradural lesions trent to be related to the formation of Rathke's pouch and closure of the anterior neuropore.

[Long-term results of the surgical treatment of spheno-orbital osteomeningioma]. / Résultats à long terme du traitement chirugical des ostéo-méningiomes sphéno-orbitaires.

The authors report a series of 21 cases of spheno-orbital "en plaque" meningiomas operated on between 1981 and 1993. All patients underwent surgery via fronto-temporal approach with orbito-zygomatic removal, followed by bone reconstruction. A complete tumor resection was performed in 15 cases. In the remaining patients, tumor resection remained subtotal, as the cavernous sinus was involved. Histological examination disclosed a low grade meningioma in 17 cases, high grade meningioma in the other patients. Radiation therapy was performed in 5 patients, when the tumoral resection was incomplete or for high grade meningiomas. The mean follow up was 7 years. One patient died in the post-operative course. Transient ophthalmoparesis occurred in 9 cases, 2 patients had pre-operative oculomotor palsy related to tumoral extension in the cavernous sinus and remained unchanged. Visual acuity remained unchanged after surgery in all patients who presented with normal visual acuity. It was unchanged or improved in 63% of patients who presented with moderate visual impairment. Despite the extent of the bone resection, the cosmetic results were good or excellent in 75% of patients, fair in 17%, and bad in 8%. Recurrence of the tumor occurred in 3 patients, with high-grade meningiomas (2 cases) or after subtotal removal of a low-grade meningioma (1 case). Orbito-fronto-temporal approach is necessary to complete the resection of the tumor extended in the orbit, the orbital fissures or the optic canal. Early operation allows a complete tumor resection before the tumor extends to the cavernous sinus.

Solitary brain metastasis as only recurrence of a carcinoma of the bladder.

A case of solitary brain metastasis from a transitional carcinoma of the bladder occurring 20 months after resection is presented. The patient underwent gross total removal followed by external irradiation and intravenous chemotherapy. The tumor in this quite unusual occurrence had a very characteristic aspect, both operatively and at pathologic examination. We believe that these patients should be managed aggressively whenever possible.

Foraminal lumbar disc herniation. Experience with 83 patients.

STUDY DESIGN: This study analyzed a series of 83 patients operated on for foraminal lumbar disc herniation. OBJECTIVES: This study sought to develop clinical and radiologic diagnoses, evaluate interlaminar and extra-articular exposures, and evaluate postoperative results. SUMMARY OF BACKGROUND DATA: Some authors have reported a specific clinical syndrome, but other reports have indicated the clinical picture is indistinguishable from usual posterolateral disc herniation. Surgical management often has been compared between the interlaminar and extra-articular approaches. METHODS: Clinical findings were reviewed. All patients were evaluated with computed tomography, but radiologic diagnosis required computed tomographic discography for 26 patients. Interlaminar exposure with partial medial facetectomy was performed in 73 patients and an extra-articular approach was necessary in 10 patients. Postoperative results were evaluated with a 2-year follow-up. RESULTS: Foraminal lumbar disc herniations have a specific clinical picture, particularly severe radicular signs. Precise preoperative radiologic evaluation is essential for successful operative procedure. Postoperative results were good in 76% of the patients. The other patients felt mild residual radicular pain, although no residual root compression was found on postoperative computed tomography. Only 21% of the patients that had a radicular deficit recovered totally. CONCLUSIONS: Foraminal lumbar disc herniation involves characteristic clinical features. Radiologic diagnosis requires high-resolution computed tomography, computed tomographic discography, or magnetic resonance imaging. Most foraminal lumbar disc herniations are reached through the interlaminar exposure extended to the upper lamina and medial facet without total facetectomy. An extra-articular approach should be reserved for extra-foraminal herniations.

Association of Lhermitte-Duclos and Cowden disease: report of a new case and review of the literature.

Lhermitte-Duclos disease is a rare entity, and its pathological features are unique. Pathological findings are characteristic of the disease, with global hypertrophy of the cerebellum, coarse gyri, and the typical "inverted cortex" pattern. Several associated lesions were noted in many patients with Lhermitte-Duclos disease. It is only recently that an association between Lhermitte-Duclos disease and Cowden disease was reported. Cowden disease, or multiple hamartomas syndrome, is a familial disease associating breast cancer, cutaneomucous tricholemmomas, and various other tumoural and dysplasic conditions. A new case of Lhermitte-Duclos disease associated with Cowden disease is reported. A review of the literature found 72 cases of Lhermitte-Duclos disease; 26 had conditions suggesting Cowden disease and seven were definite cases of Cowden disease. The association of Lhermitte-Duclos disease and Cowden disease is probably underestimated. Cowden disease represents a new form of phakomatosis; Lhermitte-Duclos disease may occur as a sporadic disease, or as part of familial Cowden disease. The possibility of preneoplastic states in Cowden syndrome stresses the importance of a thorough screening when Lhermitte-Duclos disease is diagnosed.