Safe intrathecal fluorescein use for identification of cerebrospinal fluid leaks: Case-report and perioperative algorithm description. / Uso seguro de fluoresceína intratecal en la localización de las fístulas de líquido cefalorraquídeo: descripción de un caso e implementación de un algoritmo perioperatorio.

Intrathecal injection of fluorescein is a method for repairing cerebrospinal fluid fistulas. The most frequent surgical procedure is endonasal endoscopy and the purpose of injecting this dye is to locate the fistula. The anaesthesiologists usually perform the puncture, therefore it is necessary to review this method and to specify some anaesthetic considerations such as correct dosing, safe management protocols and medical-legal aspects. In this case-report we describe the pre, intra and postoperative protocol of action implemented in our department that basically consists of: obtaining a specific consent, prior neurological/ophthalmologic assessment to rule out hypertension and brain damage, use of corticosteroids and previous antihistamines, choosing the correct dose and concentration of intrathecal sodium fluorescein (maximum 1ml at a concentration of 5% diluted in 9ml of cerebrospinal fluid) and close intra and postoperative monitoring.

Symptomatic contralateral subdural hygromas after decompressive craniectomy: plausible causes and management protocols.

OBJECT: Contralateral subdural hygromas are occasionally observed after decompressive craniectomies (DCs). Some of these hygromas are symptomatic, and the etiology and management of these symptomatic contralateral subdural collections (CLDCs) present surgical challenges. The authors share their experience with managing symptomatic CLSDCs after a DC. METHODS: During a 10-month period, 306 patients underwent a DC. Of these patients, 266 had a head injury, 25 a middle cerebral artery infarction (that is, a thrombotic stroke), and 15 an infarction due to a vasospasm (resulting from an aneurysmal subarachnoid hemorrhage [SAH]). Seventeen patients (15 with a head injury and 2 with an SAH) developed a CLSDC, and 7 of these patients showed overt symptoms of the fluid collection. These patients were treated with a trial intervention consisting of bur hole drainage followed by cranioplasty. If required, a ventriculo- or thecoperitoneal shunt was inserted at a later time. RESULTS: Seven patients developed a symptomatic CLSDC after a DC, 6 of whom had a head injury and 1 had an SAH. The average length of time between the DC and CLSDC formation was 24 days. Fluid drainage via a bur hole was attempted in the first 5 patients. However, symptoms in these patients improved only temporarily. All 7 patients (including the 5 in whom the bur hole drainage had failed and 2 directly after the DC) underwent a cranioplasty, and the CLSDC resolved in all of these patients. The average time it took for the CLSDC to resolve after the cranioplasty was 34 days. Three patients developed hydrocephalus after the cranioplasty, requiring a diversion procedure, and 1 patient contracted meningitis and died. CONCLUSIONS: Arachnoid tears and blockage of arachnoid villi appear to be the underlying causes of a CLSDC. The absence of sufficient fluid pressure required for CSF absorption after a DC further aggravates such fluid collections. Underlying hydrocephalus may appear as subdural collections in some patients after the DC. Bur hole drainage appears to be only a temporary measure and leads to recurrence of a CLSDC. Therefore, cranioplasty is the definitive treatment for such collections and, if performed early, may even avert CLSDC formation. A temporary ventriculostomy or an external lumbar drainage may be added to aid the cranioplasty and may be removed postoperatively. Ventriculoperitoneal or thecoperitoneal shunting may be required for patients in whom a hydrocephalus manifests after cranioplasty and underlies the CLSDC.

Post-traumatic meningioma: three case reports of this rare condition and a review of the literature.

We present three cases of meningiomas developing at the site of an old head trauma. We then review the literature regarding the controversies on the development of post-traumatic brain tumors and, finally, we emphasize the medico-legal characteristics of post-traumatic meningiomas, particularly with respect to their cell type which is frequently atypical or anaplastic and which have a poor outcome.

Pedunculated basilar terminus aneurysm with pseudo-septation due to anterior herniation through a perforated membrane of Liliequist.

Septations within cerebral arteries or aneurysms are exceedingly rare in the absence of associated fenestrations. We report an unusual unruptured pedunculated basilar apex aneurysm, with a "pseudoseptation" between the main aneurysmal sac and an anterior compartment, which was, in fact, represented by a perforation in the membrane of Liliequist, permitting anterior aneurysmal herniation into the carotid-chiasmatic cistern. The patient was successfully treated with detachable coils. This case is unusual on 2 accounts: 1) the aneurysm's appearance, and 2) the presence of a large fenestration in the membrane of Liliequist, of which anatomic features are herein reviewed.

Traumatic spinal-cord herniation associated with pseudomeningocele after lower-thoracic nerve-root avulsion.

BACKGROUND: Traumatic spinal-cord herniation after nerve root avulsion is rare. We report on the first patient with spinal-cord herniation associated with pseudomeningocele in the lower conus medullaris region after nerve avulsion. CASE: This 72-year-old man presented with progressive pain in the left leg and motor weakness after two traumatic accidents. Constructive interference in steady-state (CISS) imaging showed the attachment of the spinal cord to the wall of a herniated pseudomeningocele and associated syringomyelia at the level of T12. At the time of surgery, a herniated pseudomeningocele was observed. The lateral portion of the spinal cord that had herniated into the pseudomeningocele was detached from its wall; this was followed by repair of the dural defect. A redundant nerve root was observed inside the pseudomeningocele, suggesting nerve root avulsion as the primary lesion. To facilitate cerebrospinal fluid drainage from the syringomyelia, we next performed dorsal root entry zone (DREZ)tomy to the pseudomeningocele. Postoperatively, he manifested significant clinical improvement. CONCLUSIONS: This is the first report of spinal cord herniation after nerve root avulsion in the conus medullaris region. CISS imaging is highly useful for the demonstration of spinal cord herniation, syringomyelia and pseudomeningocele. To restore neurological function in patients with progressive symptoms, we recommend surgical treatment.

Cervicothoracic postarachnoiditic hydrosyringomyelia secondary to pedicular hook dislocation: case report.

BACKGROUND: Pedicular hook dislocation is a rare complication of spinal instrumentation. We report on the first case of hydrosyringomyelia secondary to intracanalar hook displacement after scoliosis surgery. CASE DESCRIPTION: A 15-year-old girl presented to our institution with a 7-month history of persistent neck and occipital pain as well as numbness of the lower extremities and previous dorsolumbar instrumentation with dorsal pedicular hooks and lumbar screws. Magnetic resonance imaging showed intramedullary cystic cavity from C5 to T7, isointense to cerebrospinal fluid (CSF) on T1- and T2-weighted images. Computed tomographic scan showed intracanalar displacement of the left hook. On admission, the patient presented with mild weakness of the lower extremities, hypalgesia below the level of T4, and urinary disturbance. The patient underwent surgical hook removal, T4 laminectomy, and midline dural opening: the arachnoid membrane was found to be thick and adhered to the dura and dorsolateral spinal cord. The arachnoid scarring was dissected, and the cord was untethered. A small posterior-median myelotomy was performed, and a syringosubarachnoid catheter was placed into the subarachnoid space to restore CSF flow. CONCLUSIONS: Late intracanalar displacement of spinal devices is an event that may complicate spinal instrumentation for scoliosis. This case highlights the importance of correct spinal device positioning and that of careful follow-up after instrumentation to detect complications early. We also discuss the pathogenetic pathway of the postarachnoiditic syringomyelia in this case.

Cefalea pospunción dural. Ultraestructura de las lesiones durales y agujas espinales usadas en las punciones lumbares / Post dural puncture cephalea. UItra-structure of the dural lesions and spinal needles used in lumbar punctures

Con el microscopio electrónico de barrido, se examinó la morfología de las lesiones durales y aracnoideas en muestras de saco dura-aracnoideo extraídos de cuerpos humanos recién fallecidos. Después de hacer punciones con agujas Quincke y Whitacre 22-G y 25-G, no se encontraron diferencias estadísticamente significativas entre las áreas de las lesiones durales y aracnoideas. La lesión tenía una morfología diferente con cada aguja. La aguja Whitacre producía una lesión de bordes rotos con gran destrucción de fibras durales, mientras que la aguja "biselada" Quincke causaba una lesión con forma de "U" o "V", como la tapa de una lata, con bordes de corte limpio. La alineación paralela o perpendicular entre el bisel de la punta de la aguja Quincke y el eje del axis no modificaba el área de las lesiones durales y aracnoideas. Se analizó cómo se puede producir cada tipo de lesión y se interpretaron los otros factores que podrían participar. Con la misma técnica se estudiaron agujas espinales nuevas obteniéndose, en cierto porcentaje de éstas, una imagen tridimensional a gran aumento de la fragmentación de puntas, defectos del pulido y existencia de rebabas. Se analizó cómo se pueden alterar las puntas de las agujas al chocar contra el hueso y de qué manera los defectos de estas constituyen otro aspecto de la compleja suma de variables que predisponen a la aparición de una cefalea pospunción dural.

The morphology of dural and arachnoid lesions was electronically scanned, from samples of dura-arachnoid sacs taken from recently deceased human beings. After punctures with Quincke y Whitacre 22-G y 25-G needles, no statistically significant differences were found between the areas of the dural and arachnoid lesions. The lesion had a different morphology with each needle. The Whitacre needle produced a lesion of broken edges with great destruction of the dural fibers, whereas the Quincke "beveled" needle caused a "U" or "V" shaped lesion, like the lid of a can, with clean-cut edges. The parallel or perpendicular alignment between the bevel of the Quincke needle tip and the axis of the axis did not modify the area of the dural and arachnoid lesions. A study was made of how each type of lesion could have come about and of other possible participating factors. The same technique was used to study new spinal needles and, in a certain percentage, a three dimensional image was obtained, showing a great increase in the fragmentation of the tips, burnish defects and the existence of burrs. We also analyzed how hitting against the bone could affect the tips of the needles and how their defects could be another factor in the complex sum of variables that predispose the patient to suffer post dural puncture cephalea.

Com o microscópio eletrônico de varredura, examinou-se a morfologia das lesoes durais e da aracnóide em amostras de saco dural-aracnóideo extraídos de corpos humanos de recem-falecidos. As diferencas entre as áreas das lesoes durais e da aracnóide pós-puncao com agulhas Quincke e Whitacre 22-G e 25-G nao foram estatisticamente significativas, e a morfologia da lesao causada com cada agulha foi diferente. A agulha Whitacre provocou lesao de bordas rompidas com grande destruicao de fibras durais, enquanto a agulha "biselada" Quincke causou lesao com forma de "U" ou "V", como a tampa de uma lata, com bordas de corte limpo. O alinhamento paralelo ou perpendicular do bisel da ponta da agulha Quincke com o eixo do áxis nao modificou a área das lesóes durais e da aracnóide. Foram analisadas as causas de cada tipo de lesao e interpretados outros fatores envolvidos. Utilizando a mesma técnica, avaliaram-se imagens tridimensionais de algumas agulhas espinhais novas tiradas com grande aumento: fragmentacao das pontas, defeitos de polimento e presenca de rebarbas. Avaliou-se também como se modificam as pontas das agulhas ao atingirem o osso e a influência dos defeitos das pontas na complexa soma de variáveis que predispoem o aparecimento de cefaléia pós-puncao dural.

Effect of arachnoid plasty using fibrin glue membrane after clipping of ruptured aneurysm on the occurrence of complications and outcome in the elderly patients.

BACKGROUND: In elderly patients with aneurysmal subarachnoid hemorrhage (SAH), complications including vasosopasm, subdural effusion, and late hydrocephalus, are liable to occur even after aneurysmal surgery. We examined prospectively the efficacy of arachnoid plasty using fibrin glue membrane during surgery of ruptured aneurysms in the elderly patients for preventing complications. The effects on the modified Rankin scale (mRS) and the Glasgow outcome scale (GOS) 3 months after SAH were noted. METHODS: Total of 31 patients aged more than 70 years selected from a consecutive series of patients with aneurysmal SAH, were divided into two groups alternately, a group with arachnoid plasty (n = 16) and a control group without arachnoid plasty (n = 15). Statistical analyses were performed to assess relationships among various clinical and neuroradiological variables, especially between arachnoid plasty and occurrence of symptomatic vasospasm, subdural effusion, late hydrocephalus, or outcome such as mRS and GOS 3 months after onset. FINDINGS: Statistical analyses revealed that arachnoid plasty were associated with late hydrocephalus and subdural effusion negatively, but with better mRS at 3 months after SAH. A tendency to be associated with less frequent symptomatic vasospasm was also noted. CONCLUSION: Arachnoid plasty using fibrin glue is suggested to be effective in preventing complications associated with SAH and aneurysmal surgery. A better outcome in the elderly patients can be achieved.

Dura-arachnoid lesions produced by 22 gauge Quincke spinal needles during a lumbar puncture.

AIMS: The dural and arachnoid hole caused by lumbar puncture needles is a determining factor in triggering headaches. The aim of this study is to assess the dimensions and morphological features of the dura mater and arachnoids when they are punctured by a 22 gauge Quincke needle having its bevel either in the parallel or in the transverse position. METHODS: Fifty punctures were made with 22 gauge Quincke needles in the dural sac of four fresh cadavers using an "in vitro" model especially designed for this purpose. The punctures were performed by needles with bevels parallel or perpendicular to the spinal axis and studied under scanning electron microscopy. RESULTS: Thirty five of the 50 punctures done by Quincke needles (19 in the external surface and 16 in the internal) were used for evaluation. When the needle was inserted with its bevel parallel to the axis of the dural sac (17 of 35), the size of the dura-arachnoid lesion was 0.032 mm(2) in the epidural surface and 0.037 mm(2) in the subarachnoid surface of the dural sac. When the needle's bevel was perpendicular to the axis (18 of 35) the measurement of the lesion size was 0.042 mm(2) for the external surface and 0.033 mm(2) for the internal. There were no statistical significant differences between these results. CONCLUSIONS: It is believed that the reported lower frequency of postdural puncture headache when the needle is inserted parallel to the cord axis should be explained by some other factors besides the size of the dura-arachnoid injury.

Multi-level disruption of the spinal nerve root sleeves in spontaneous spinal cerebrospinal fluid leakage--two case reports.

A 37-year-old male and an 18-year-old male presented with spontaneous spinal cerebrospinal fluid (CSF) leakage from multiple nerve root sleeves. Both patients suffered abrupt onset of intense headache followed by nausea, dizziness, and one patient with and one without positional headache. Radioisotope spinal cisternography of both patients revealed that the CSF leaks were not localized in a special zone but distributed to multiple spinal nerve root sleeves. Magnetic resonance (MR) myelography suggested that the spinal CSF column was fully expanded to the root sleeves. The extraspinal nerve bundles demonstrated numerous high intensity spots. Both patients were treated conservatively, and their symptoms resolved within one month. Repeat radioisotope cisternography and MR myelography confirmed the spine was normal after recovery. We suggest that spreading disruption of the arachnoid membrane occurs at the nerve root sleeves due to CSF overflow into the spinal canal.

External hydrocephalus after aneurysm surgery: paradoxical response to ventricular shunting.

OBJECT: The authors sought to investigate the mechanisms and pathophysiological effects of subdural fluid collection after surgery for aneurysmal subarachnoid hemorrhage (SAH). METHODS: The authors retrospectively analyzed the medical records of 76 patients who had undergone craniotomy. The patients included 55 with aneurysmal SAH (SAH group) and 21 with unruptured aneurysms (non-SAH group) who were used as controls. Subdural fluid collection was more common in the SAH than in the non-SAH group (38% compared with 14%, p < 0.05). Although older patients appeared to be at greater risk for subdural fluid collection in both groups (p < 0.05), this condition developed even in relatively young patients with SAH. In the SAH group most subdural fluid collection was associated with ventricular dilation (81%), and a significant correlation was seen between fluid collection and the need for subsequent shunt placement (48% compared with 21%, p < 0.05). These results point to an association between hydrodynamic dysfunction and subdural fluid collection. The course of patients with subdural fluid collection varied from spontaneous resolution to normal-pressure hydrocephalus. Seven patients with persistent subdural collections underwent shunt placement (ventriculoperitoneal [VP] shunt in six and lumboperitoneal in one), which resulted in resolution of fluid collection in all seven. CONCLUSIONS: The results indicate that for most patients in the SAH group, subdural fluid collection represented "external hydrocephalus" rather than simple "subdural hygroma." Decreased absorption of cerebrospinal fluid because of SAH and surgically created tears in the arachnoid membrane communicating with the subdural space were factors in the development of external hydrocephalus. The authors believe that differentiating external hydrocephalus from subdural hygroma is extremely important, because VP shunt placement can be used to treat the former but could worsen the latter.

Intraspinal extradural arachnoid cyst with spinal cord herniation.

A 17-year-old male presented with thoracic myelopathy 12 months after a stab injury to the thoracic spine. The patient reported that symptoms and signs had gradually worsened in the 3 months prior to his examination. Magnetic resonance imaging depicted not only an extradural arachnoid cyst but severe spinal cord compression. The cerebrospinal fluid pressure and dynamics associated with herniation of the spinal cord resulted in the formation and enlargement of an extradural arachnoid cyst. The pressure effect of the cyst accounted for the thoracic myelopathy.

Symptomatic subdural hygroma as a complication of foramen magnum decompression for hindbrain herniation (Arnold-Chiari deformity).

Pseudomeningocele is a well known complication of foramen magnum decompression. Symptomatic subdural hygroma has not previously been described. We discuss a case of Arnold Chiari malformation type 1 in a 55-year-old Caucasian woman who underwent foramen magnum and upper cervical decompression and who developed a symptomatic subdural hygroma 2 weeks following surgery. This complication was most likely due to a technical error during surgery. It responded favourably to conservative therapy.

Sudden onset of subarachnoid block after subdural catheterization: a case of arachnoid rupture?

We describe a patient who received an apparently uneventful extradural block in labour but developed rapid extension of neural block within minutes of receiving her first incremental dose 2 h later. Computed contrast tomography revealed radio-opaque dye within both the subdural and subarachnoid spaces, but none within the extradural space. This case report demonstrates that subdural spread of low-dose local anaesthetics is not always clinically distinguishable from extradural analgesia and that the arachnoid membrane may subsequently perforate with potentially serious consequences.

Herniation of the spinal cord 38 years after childhood trauma.

We report an unusual post-traumatic spinal cord herniation, which became symptomatic 38 years after the trauma. A 44-year-old man presented with a 2-year history of increasing impotence, neuropathic bladder dysfunction and dissociated sensory loss below the level of T6. At the age of 6 years he had a severe blunt spinal injury with transient paraparesis. MRI revealed right lateral and ventral displacement of the spinal cord at the T5/6 level. The spinal cord was surgically exposed and found to herniate through a ventral defect of the arachnoid membrane and the dura mater. As there were no other events that could have precipitated spinal cord herniation the reported blunt trauma in childhood is the most likely cause for the spinal cord herniation in this patient.