Significance of empty sella in cerebrospinal fluid leaks.

OBJECTIVE: The role of elevated cerebrospinal fluid (CSF) pressures in the pathophysiology of various CSF leaks is not clear. Empty sella syndrome (ESS) is a radiographic finding that can be associated with elevated CSF pressures and may represent a radiographic indicator of intracranial hypertension. We present our experience with CSF leaks of various causes, the prevalence of ESS in the spontaneous and nonspontaneous categories, and the potential pathophysiology and unique management issues of the spontaneous CSF leak group. METHODS: We conducted a retrospective review of medical records, imaging studies, and surgical treatment of CSF leaks in patients treated by the senior author. RESULTS: Sixteen patients with spontaneous CSF leaks and 12 patients with nonspontaneous CSF leaks were surgically treated from 1996 through 2002. In the spontaneous group, 15 patients had complete imaging of the sella turcica. Ten had completely empty sellae and 5 had partially empty sellae, for a total of 100% (15 of 15). In the nonspontaneous group, 9 patients had complete imaging of the sella. Only 11% (1 of 9) had a partially empty sella and that was a congenital leak. Comparison of proportions between these 2 groups was significant (P = 0.01). The spontaneous group consisted primarily of obese, middle-aged females (13 of 16 patients). CONCLUSION: Empty sella probably represents a sign of elevated intracranial pressure that leads to idiopathic, spontaneous CSF leaks. Spontaneous CSF leaks are strongly associated with the radiographic finding of an empty sella and are more common in obese females, similar to benign intracranial hypertension. This unique population may require more aggressive surgical and medical treatment to prevent recurrent or multiple leaks.     

Spontaneous CSF leaks: A paradigm for definitive repair and management of intracranial hypertension

OBJECTIVE: To report our outcomes with the repair of spontaneous cerebrospinal fluid (CSF) leaks and to demonstrate how management of underlying intracranial hypertension improves outcomes. STUDY DESIGN: Retrospective review of spontaneous CSF leaks treated at the University of Pennsylvania Health System from 1996 to 2006. Data collected included demographics, nature of presentation, body mass index (BMI), site of skull base defect, surgical approach, intracranial pressure, and clinical follow-up. RESULTS: Fifty-six patients underwent repair of spontaneous CSF leaks. Eighty-two percent (46 of 56) were obese (average BMI 36.2 kg/m(2)). Nine patients had multiple CSF leaks. Fifty-four patients (96%) had associated encephaloceles. Fifty-three CSF leaks (95%) were successfully repaired at first attempt (34 months of follow-up). Intracranial pressures averaged 27 cm H(2)O. Patients were treated with acetazolamide or, in severe cases, with a ventriculoperitoneal shunt. CONCLUSIONS: Spontaneous CSF leaks have the highest recurrence rate of any etiology. With treatment of underlying intracranial hypertension coupled with endoscopic repair, the success rate (95%) approaches that of other etiologies of CSF leaks.     

Subdural hematoma after thoracoabdominal aortic aneurysm repair: an underreported complication of spinal fluid drainage?

OBJECTIVE: Cerebrospinal fluid (CSF) drainage is a commonly used adjunct to thoracoabdominal aortic aneurysm (TAAA) repair that improves perioperative spinal cord perfusion and thereby decreases the incidence of paraplegia. To date, little data exist on possible complications, such as subdural hematoma caused by stretching and tearing of dural veins, should CSF drainage be excessive. We reviewed our experience with patients in whom postoperative subdural hematomas were detected. METHODS: The records of 230 patients who underwent TAAA repair at the Johns Hopkins Hospital between January 1992 and February 2001 were reviewed. RESULTS: Eight patients had subdural hematomas (3.5%). The four men and four women had a mean age of 60.6 years; two of these patients had a connective tissue disorder. All patients had lumbar drains placed before surgery, including one patient who underwent an emergency operation for rupture. Drains were set to allow drainage for CSF pressure greater than 5 cm H(2)O in all but one patient set for 10 cm H(2)O; spinal cooling was not performed in any patient. All drains were removed on the third postoperative day. In patients in whom subdural hematomas developed, the mean amount of CSF removed after surgery was 690 +/- 79 mL, which was significantly greater than the amount drained from patients in whom subdural hematomas did not develop (359 +/- 24 mL; P =.0013, Mann-Whitney U test). Six patients had postoperative subdural hematomas detected during hospitalization (mean postoperative day, 9.3; range, 2 to 16), and two patients were seen in delayed fashion after discharge from the hospital at 1.5 and 5 months. Four patients died of the subdural hematoma (50%); only one of these patients had neurosurgical intervention. All four survivors responded to neurosurgical intervention and are neurologically healthy. Two patients, both of whom were seen in delayed fashion, needed a lumbar blood patch. Multivariate logistic regression identified the volume of CSF drained as the only variable predictive of occurrence of subdural hematoma (P =.01). CONCLUSION: Subdural hematoma is an unusual and potentially catastrophic complication after TAAA repair. Prompt recognition and neurosurgical intervention is necessary for survival and recovery after acute presentation. Epidural placement of a blood patch is recommended if a chronic subdural hematoma is detected. Care should be taken to ensure that excessive CSF is not drained perioperatively, and higher (10 cm H(2)O) lumbar drain popoff pressures may be necessary together with meticulous monitoring of patient position and neurologic status.     

Prolonged Jackson-Pratt drainage in the management of lumbar cerebrospinal fluid leaks

BACKGROUND: Cerebrospinal fluid (CSF) leak is a complication of spinal surgery. Intraoperative or postoperative identification of a CSF leak often results in wound healing complications, lumbar drain placement, and/or reoperation. These complications usually extend a patient's hospital stay, can be painful, and have their own associated risks. The authors describe a technique that may improve on traditional interventions by managing postoperative CSF leaks after lumbar instrumentation without an additional procedure or extended hospitalization. METHODS: A retrospective review of lumbar instrumentation cases performed by 5 attending surgeons from the Division of Neurosurgery, University of California at San Diego, was performed. In all, 184 charts were reviewed, spanning a 3-year period. There were 16 cases in which a dural tear and repair were carried out and subsequently treated with subfascial Jackson-Pratt (JP) drainage. Of those 16 cases, 8 patients were managed with prolonged JP drainage using the intraoperatively placed subfascial drain. Patients were discharged home on oral antibiotics according to the customary criteria with the JP drain in place and were instructed regarding proper drain maintenance. Jackson-Pratt drains were removed in clinic in a delayed fashion, approximately 10 to 17 days postoperatively. Patients were subsequently reevaluated at regular intervals for any persistent CSF leak. RESULTS: In the 8 cases reviewed, all patients were discharged in a time frame comparable to that of patients undergoing similar instrumentation in which no CSF leak was identified, or in whom a CSF leak was identified and repaired intraoperatively. No patients suffered complications arising from prolonged drain presence. No patients suffered from persistent CSF leak after drains were removed. CONCLUSION: Our study suggests that routine intraoperative subfascial JP drain placement aids in the early diagnosis of postoperative lumbar CSF leak. Primary closure of dural tear remains the standard of care. Furthermore, in select cases, prolonged JP drainage in the setting of postoperative CSF leak may be a useful technique for the treatment of these leaks.     

Use of Tisseel fibrin sealant in neurosurgical procedures: incidence of cerebrospinal fluid leaks and cost-benefit analysis in a retrospective study

OBJECTIVE: To determine the clinical efficacy and cost effectiveness of using the fibrin sealant (FS) Tisseel (Baxter Healthcare Corp., Deerfield, IL) for patients undergoing anterior cranial base, infratemporal, and retromastoid surgical procedures. METHODS: A retrospective review was performed, comparing two matched populations of patients who underwent surgical procedures using anterior cranial, infratemporal, or retromastoid approaches to intracranial pathological lesions. The incidences of cerebrospinal fluid (CSF) leaks in matched groups treated with the FS Tisseel or treated without FS were compared. The costs of Tisseel use were examined in comparison with the costs of postoperative management of CSF leaks and/or tension pneumocranium with spinal drainage and occasionally surgical reexploration, when lumbar drainage failed. RESULTS: Patients who received the FS Tisseel exhibited no detectable postoperative CSF leaks or tension pneumocranium. Patients who did not receive Tisseel demonstrated 4 to 16% incidences of postoperative leaks, depending on the surgical approach used. The costs of treating those leaks far exceeded the costs of using Tisseel, even if it were used indiscriminately for all patients. CONCLUSION: This retrospective review indicates that the FS Tisseel reduces the incidence of postoperative CSF leaks and tension pneumocranium while reducing overall management costs. Further prospective study is needed to determine which patients can benefit most from FS use.     

BioGlue for prevention of postoperative cerebrospinal fluid leaks in transsphenoidal surgery: A case series

BACKGROUND: The efficacy of BioGlue (CryoLife, Inc, Atlanta, Ga) surgical adhesive in transsphenoidal surgery was assessed as an adjunct in the prevention of postoperative CSF leaks. METHODS: All patients in whom BioGlue was used for an intraoperative skull base reconstruction were retrospectively identified. Intraoperative CSF leaks were graded according to size (grade 1, small weeping leak without obvious diaphragmatic defect; grade 2, moderate leak with a definite diaphragmatic defect; grade 3, large diaphragmatic and/or dural defect). CSF leak repair was tailored to CSF leak grade. BioGlue was applied as a reinforcement over collagen sponge as the last layer of the repair. RESULTS: Over 28 months, a total of 282 patients underwent endonasal surgery. Of these patients, 124 (79 women; age range, 8-84 years), in 128 procedures, had an intraoperative CSF leak repair reinforced with BioGlue. Pathology included 80 pituitary adenomas, 11 craniopharyngiomas, 7 Rathke's cleft cysts, 6 chordomas, 5 meningiomas, 4 spontaneous CSF leaks, 3 arachnoid cysts, and 8 other parasellar pathologies. There were 62 (48.4%) grade 1, 41 (32.0%) grade 2, and 25 (19.5%) grade 3 leak repairs. The overall repair failure rate was 1.6% (2 cases), with the failures occurring in patients with grade 3 leaks, including 1 who developed meningitis; there was no failure of grades 1 and 2 leaks. The 2 failures were attributed largely to technical aspects of the repair rather than to failure of BioGlue per se. CONCLUSIONS: BioGlue appears to be an effective adjunct in preventing postoperative CSF leaks after transsphenoidal surgery. However, careful attention to technical details of the repair is still required to prevent failures, especially when closing large dural and diaphragmatic defects.     

Subcranial transnasal repair of cerebrospinal fluid rhinorrhea with free autologous grafts by the combined overlay and underlay techniques.

OBJECTIVE: To determine the efficacy of subcranial transnasal repair of cerebrospinal fluid rhinorrhea with free autologous grafts by the combined overlay and underlay techniques using the surgical microscope and/or endoscope. PATIENTS AND METHODS: Twenty patients with CSF rhinorrhea were included in this retrospective study. They were 13 males and 7 females. Their age ranged from 7 to 62 years (mean: 39.35). The etiologies of the leak were iatrogenic in 10 cases, spontaneous in 5 cases, traumatic in 4 cases and one case was associated with meningeo-encephalocele. Preoperative nasal endoscopic examination, computed tomography (CT) with intrathecal non-ionic contrast and magnetic resonance imaging (MRI) were done when indicated. Endoscopic and/or microscopic repair of the CSF fistula was done by a combination of both underlay and overlay repair with free autologous grafts as follows: Gelfoam with fibrin glue, strips of fat, facia lata, Gelfoam with fibrin glue (underlay), septal cartilage, Gelfoam with fibrin glue and strips of fat (overlay). RESULTS: Complete closure of the leak was achieved in all patients. In one case of spontaneous CSF leak which was operated endoscopically, the leak recurred 6 months postoperatively and ceased spontaneously after a month with conservative medical treatment. No major complications were seen and no patients developed meningitis or postoperative anosmia. CONCLUSION: Subcranial transnasal repair with free autologous grafts by the combined overlay and underlay techniques using the endoscope or surgical microscope is a safe and successful method of treating CSF leaks, provided that the CSF leak is precisely located and the site can be reached with the endoscope or surgical microscope.     

Recurrent spontaneous spinal cerebrospinal fluid leaks and intracranial hypotension: a prospective study

OBJECT: Intracranial hypotension due to a spontaneous spinal cerebrospinal fluid (CSF) leak is an increasingly recognized cause of postural headaches, but reliable follow-up data are lacking. The authors undertook a study to determine the risk of a recurrent spontaneous spinal CSF leak. METHODS: The patient population consisted of a consecutive group of 18 patients who had been evaluated for consideration of surgical repair of a spontaneous spinal CSF leak. The mean age of the 15 women and three men was 38 years (range 22-55 years). The mean duration of follow up was 36 months (range 6-132 months). The total follow-up time was 654 months. A recurrent spinal CSF leak was defined on the basis of computerized tomography myelography evidence of a CSF leak in a previously visualized but unaffected spinal location. Five patients (28%) developed a recurrent spinal CSF leak; the mean age of these four women and one man was 36 years. A recurrent CSF leak developed in five (38%) of 13 patients who had undergone surgical CSF leak repair, compared with none (0%) of five patients who had been treated non-surgically (p = 0.249). The recurrent leak occurred between 10 and 77 months after the initial CSF leak, but within 2 or 3 months of successful surgical repair of the leak in all patients. CONCLUSIONS: Recurrent spontaneous spinal CSF leaks are not rare, and the recent successful repair of such a leak at another site may be an important risk factor.     

A simple and reliable technique to monitor intracranial pressure in the rat: technical note.

A technique for intracranial pressure (ICP) monitoring in the rat that uses a permanent cisterna magna cannula is described. The cannula is placed into the subarachnoid space through the atlanto-occipital membrane with the operating microscope and is secured with cement. The distal end is connected to a pressure transducer and a polygraph recorder. To study the consistency of this technique, 12 anesthetized adult rats were subjected to baseline ICP measurements 2 days after placement of the cannula. Baseline pressures ranged between 1.0 and 10.0 cm H2O, with a mean of 5.6 cm H2O. Respiratory variations were detected in all tracings, and manual abdominal compressions (Valsalva maneuver) correlated with immediate transient rises in ICP in all rats. While CSF pressure was being continuously monitored, rats were subjected to subarachnoid hemorrhage induced by transclival basilar artery puncture. Of the 12 rats, 10 showed a moderate transient rise in cerebrospinal fluid pressure, which peaked approximately 2 minutes after subarachnoid hemorrhage (mean peak change, 10.5 cm H2O; range, 0-32.5 cm H2O). Reliable pressure tracings were obtained in three of five animals examined 3 days after subarachnoid hemorrhage (ICP range, 4.0-4.5 cm H2O; mean, 4.2 cm H2O). We conclude that this cannula is easy and inexpensive to construct and that it provides reliable ICP tracings during experimental procedures in the rat.     

Lumbar peritoneal shunting with video-laparoscopic assistance: a useful technique for the management of refractory postoperative lumbar CSF leaks

BACKGROUND: Cerebrospinal fistulas and pseudomeningoceles can occur after lumbar spinal surgery, and are sometimes refractory to direct repair, external drainage, and blood patches. The authors report a technique for cerebrospinal fluid (CSF) diversion from the lumbar spine to the peritoneum to assist with the management of these difficult situations. METHODS: Using video-laparoscopic assistance, two shunts are placed from the lumbar region into the peritoneal cavity: first, a lumbar subarachnoid space to peritoneum shunt; and second, a meningocele cavity to peritoneum shunt. Patients are ambulated immediately after the procedure. External drains are not used. RESULTS: Four patients with refractory CSF leaks were successfully managed with this technique. Complications associated with prolonged bedrest and external drains were avoided. Ancillary procedures were minimized, and hospital stay was shortened. Laparoscopic assistance offered verification of accurate placement of the peritoneal catheter and shortened operative times. CONCLUSIONS: Dual lumbar peritoneal shunts (intrathecal-peritoneal and meningocele cavity-peritoneal), placed with laparoscopic assistance, proved effective in the management of four patients with postoperative lumbar CSF leaks, who had failed to respond to conventional treatment.     

Conjunctival oedema as a potential objective sign of intracranial hypertension: a short illustrated review and three case reports

Periorbital and conjunctival oedema has been reported anecdotally by patients with raised intracranial pressure states. We present three clinical cases of this phenomenon and discuss the current evidence for pathways by which cerebrospinal fluid (CSF) drains in relation to conjunctival oedema. We reviewed the available literature using PubMed, in regards to conjunctival oedema as it relates to intracranial hypertension, and present the clinical history, radiology and orbital photographs of three cases we have observed. Only one previous publication has linked raised intracranial pressure (ICP) to conjuctival oedema. The weight of evidence supports the observation that the majority of CSF drains along the cranial nerves as opposed to via the arachnoid projections. Conjunctival oedema may be a clinical manifestation of CSF draining via the optic nerve in elevated ICP states.     

Cerebrospinal fluid pulse pressure method: a possible substitute for the examination of B waves

OBJECT: The appearance of numerous B waves during intracranial pressure (ICP) registration in patients with idiopathic adult hydrocephalus syndrome (IAHS) is considered to predict good outcome after shunt surgery. The aim of this study was to describe which physical parameters of the cerebrospinal fluid (CSF) system B-waves reflect and to find a method that could replace long-term B-wave analysis. METHODS: Ten patients with IAHS were subjected to long-term registration of ICP and a lumbar constant-pressure infusion test. The B-wave presence, CSF outflow resistance (R(out)), and relative pulse pressure coefficient (RPPC) were assessed using computerized analysis. The RPPC was introduced as a parameter reflecting the joint effect of elastance and pulsatory volume changes on ICP and was determined by relating ICP pulse amplitudes to mean ICP. CONCLUSIONS: The B-wave presence on ICP registration correlates strongly with RPPC (r = 0.91, p < 0.001, 10 patients) but not with CSF R(out). This correlation indicates that B waves-like RPPC-primarily reflect the ability of the CSF system to reallocate and store liquid rather than absorb it. The RPPC-assessing lumbar short-term CSF pulse pressure method could replace the intracranial long-term B-wave analysis.     

A management algorithm for cerebrospinal fluid leak associated with anterior skull base fractures: detailed clinical and radiological follow-up

Detailed outcome data for the management of anterior skull base fractures associated with cerebrospinal fluid (CSF) leakage is lacking. We present detailed follow-up data of a single-center study using a predetermined algorithm for the management of CSF leakage secondary to traumatic fractures. A number of 138 consecutive patients were included in the analysis; all patients underwent high-resolution computed tomography (CT) scanning at time of admission with β₂-transferrin testing used to confirm CSF leakage. Patients with acute surgical indications were operated as emergent; leaks were repaired at the time of initial surgery in patients with intracranial pressure < 15 cm H₂O. The remainder of the study population was managed conservatively including use of prophylactic antibiotics; lumbar drainage (LD) catheters were placed in those patients with leakage persisting beyond 48 h. Leaks lasting longer than 5 days underwent microsurgical repair using an intradural bicoronal approach. One-year follow-up assessment included evaluation of neurological status, Glasgow Outcome Scale (GOS), and repeat head CT. Twenty eight patients (26.9%) underwent emergent surgery, 15 of whom had simultaneous CSF leak repair, whereas 76 patients (73.1%) underwent delayed CSF leak repair between days 5 and 14. Postoperative meningitis rate was low (1.9%). Postoperative CSF leak (1.9%) was managed by intradural or transnasal endoscopic operation. Comparable rates of anosmia and frontal lobe hypodensities were seen in the surgical and conservatively managed subgroups. The presented algorithm, utilizing prophylactic antibiotics, trial of LD, acute and/or delayed intradural microsurgery, yields favorable outcomes. Large randomized controlled trials are needed to better define the role of prophylactic antibiotics and to better characterize the optimal timing and approach of surgical repair.     

Primary empty sella syndrome in a series of 142 patients

OBJECT: The primary empty sella syndrome (ESS) represents a heterogeneous clinical picture characterized by endocrine disturbances and signs of intracranial hypertension. An increase in intracranial pressure (ICP) is proposed to be one of the involved pathogenetic factors. METHODS: The series included 142 patients who were observed during a period of 20 years. All patients underwent an ICP and cerebrospinal fluid (CSF) dynamics evaluation through the use of a lumbar constant-rate infusion test. Impairment of ICP and CSF dynamics was observed in 109 patients (76.8%). In 35 of the 36 patients affected by severe intracranial hypertension without rhinorrhea, improvement in adverse neurological symptoms was achieved after implanting a CSF shunt. Visual function, already seriously compromised before surgery, remained severely altered in one patient. In the group of 34 patients affected by rhinorrhea, CSF leakage was controlled using different surgical treatments: CSF shunt placement in 16 cases, surgical repair of the sellar floor in three, and both procedures in the remaining 13. Two patients refused any surgical treatment. CONCLUSIONS: The role of increased ICP in the pathogenesis and perpetuation of primary ESS has been confirmed. Adverse neurological signs and a CSF leak are correlated with an actual increase in ICP and are relieved after CSF shunt insertion. Cerebrospinal fluid rhinorrhea is more common than generally thought. Its resolution can be achieved using a careful diagnostic protocol and sometimes may require different surgical procedures.     

Cerebrospinal fluid leak after acoustic neuroma surgery: influence of tumor size and surgical approach on incidence and response to treatment

OBJECT: The aims of this study were to review the incidence of cerebrospinal fluid (CSF) leakage complicating the removal of acoustic neuroma and to identify factors that influence its occurrence and treatment. METHODS: Prospective information on consecutive patients who underwent operation for acoustic neuroma was supplemented by a retrospective review of the medical records in which patients with CSF leaks complicating tumor removal were identified. This paper represents a continuation of a previously published series and thus compiles the authors' continuous experience over the last 24 years of practice. In 624 cases of acoustic neuroma the authors observed an overall incidence of 10.7% for CSF leak. The rate of leakage was significantly lower in the last 9 years compared with the first 15, most likely because of the abandonment of the combined translabyrinthine (TL)-middle fossa exposure. There was no difference in the leakage rate between TL and retrosigmoid (RS) approaches, although there were differences in the site of the leak (wound leaks occurred more frequently after a TL and otorrhea after an RS approach, respectively). Tumor size (maximum extracanalicular diameter) had a significant effect on the leakage rate overall and for RS but not for TL procedures. The majority of leaks ceased with nonsurgical treatments (18% with expectant management and 49% with lumbar CSF drainage). However, TL leaks (especially rhinorrhea) required surgical repair significantly more often than RS leaks. This has not been reported previously. CONCLUSIONS: The rate of CSF leakage after TL and RS procedures has remained stable. Factors influencing its occurrence include tumor size but not surgical approach. The TL-related leaks had a significantly higher surgical repair rate than RS-related leaks, an additional factor to consider when choosing an approach. The problem of CSF leakage becomes increasingly important as nonsurgical treatments for acoustic neuroma are developed.     

Management morbidity and mortality of poor-grade aneurysm patients

Preliminary experience with the occasional good survival of patients in Hunt and Hess Grade IV or V with aneurysmal subarachnoid hemorrhage (SAH) led to a prospective management protocol employed during a 2 1/2-year period. The protocol utilized computerized tomography (CT) scanning to diagnose SAH and to obtain evidence for irreversible brain destruction, consisting of massive cerebral infarction with midline shift or dominant basal ganglia or brain-stem hematoma. These patients, along with those who exhibited poor or absent intracranial filling on CT or angiography, were excluded from active treatment and given supportive care only. All other patients had immediate ventriculostomy placement and, if intracranial pressure (ICP) was controllable (less than or equal to 30 cm H2O without an intracranial clot or less than or equal to 50 cm H2O in the presence of a clot), went on to have craniotomy for aneurysm clipping. Aggressive postoperative hypertensive, hypervolemic, hemodilutional therapy was subsequently employed. Of 54 patients with poor-grade aneurysms, ventriculostomy was placed in 47 (87.0%) and yielded high ICP's in the overwhelming majority, with the mean ICP being 40.2 cm H2O. Nineteen poor-grade aneurysm patients received no surgical treatment and survived a mean of 31.8 hours with 100% mortality. Thirty-five patients underwent placement of a ventriculostomy, craniotomy for aneurysm clipping and intracranial clot evacuation, and postoperative hypertensive, hypervolemic, hemodilutional therapy. The outcome at 3 months of the 35 patients who were selected for active treatment was good in 19 (54.3%), fair in four (11.4%), poor in four (11.4%), and death in eight (22.9%). It is concluded that poor-grade aneurysm patients usually present with intracranial hypertension, even those without an intracranial clot. Based on radiographic rather than neurological criteria, a portion of these patients can be selected for active and successful treatment. Increased ICP can be present without ventriculomegaly, and immediate ventriculostomy should be performed. As long as ICP is controllable, craniotomy and postoperative intensive care can effect a favorable outcome in a significant percentage of these patients.     

False localizing sign of C1-2 cerebrospinal fluid leak in spontaneous intracranial hypotension

OBJECT: Spontaneous intracranial hypotension due to a spinal cerebrospinal fluid (CSF) leak is an important cause of new daily persistent headaches. Spinal neuroimaging is important in the treatment of these patients, particularly when direct repair of the CSF leak is contemplated. Retrospinal C1-2 fluid collections may be noted on spinal imaging and these are generally believed to correspond to the site of the CSF leak. The authors undertook a study to determine the significance of these C1-2 fluid collections. METHODS: The patient population consisted of a consecutive group of 25 patients (18 female and seven male) who were evaluated for surgical repair of a spontaneous spinal CSF leak. The mean age of the 18 patients was 38 years (range 13-72 years). All patients underwent computerized tomography myelography. Three patients (12%) had extensive retrospinal C1-2 fluid collections; the mean age of this woman and these two men was 41 years (range 39-43 years). The actual site of the CSF leak was located at the lower cervical spine in these patients and did not correspond to the site of the retrospinal C1-2 fluid collection. CONCLUSIONS: A retrospinal fluid collection at the C1-2 level does not necessarily indicate the site of the CSF leak in patients with spontaneous intracranial hypotension. This is an important consideration in the treatment of these patients because therapy may be inadvertently directed at this site.     

Utilization of preoperative cerebrospinal fluid drain in skull base surgery.

OBJECTIVE: Retrospectively assess the efficacy of lumbar cerebrospinal fluid (CSF) drainage placed preoperatively in skull base operations in decreasing the incidence of postoperative CSF fistula. METHODS: A retrospective review of 150 patients undergoing a posterior fossa craniotomy from 1989 to 2000 was conducted. Patients were divided into those receiving preoperative lumbar drains and those that did not. The rates of postoperative CSF leakage were compared between the two groups. Patient data were analyzed to determine if there were other comorbidities affecting the postoperative incidence of CSF leakage such as smoking, diabetes, or hypertension. RESULTS: Between 1989 and 1994, 25/72 (35%) patients with no preoperative lumbar drain had a postoperative CSF leak. From 1995 to 2000, 9/78 (12%) patients with a preoperative lumbar drain had a CSF leak. This was a 23% decreased incidence of postoperative CSF leakage and a significant decrease in the probability (p < 0.001) of CSF leakage in patients treated with a preoperative lumbar drain. The comorbidities of diabetes, smoking, or hypertension did not increase the probability of a CSF leak (p = 0.43). CONCLUSIONS: A preoperatively placed lumbar drain can significantly lower the rate of postoperative CSF leakage after skull base surgery. The drain is a well-tolerated adjunct to dural closure and helps increase surgical exposure of the posterior fossa. The comorbidities of diabetes, smoking, or hypertension do not contribute to an increased rate of CSF leakage.dagger Lyal Leibrock M.D., F.A.C.S. is Deceased.     

Treatment of traumatic cerebrospinal fluid rhinorrhea via extended extradural anterior skull base approach

Objective: To describe and assess the repair technique and perioperative management for cerebrospinal fluid (CSF) leak resulting from extensive anterior skull base fracture via extradural anterior skull base approach. Methods: This was a retrospective review conducted at the Department of Neurosurgery of the Shanghai Tenth People''s Hospital from January 2015 to April 2020. Patients with traumatic CSF rhinorrhea resulting from extensive anterior skull base fracture treated surgically via extended extradural anterior skull base approach were included in this study. The data of medical and radiological records, surgical approaches, repair techniques, peritoperative management, surgical outcome and postoperative followup were analyzed. Surgical repair techniques were tailored to the condition of associated injuries of the scalp, bony and dura injuries and associated intracranial lesions. Patients were followed up for the outcome of CSF leak and surgical complications. Data were presented as frequency and percent. Results: Thirty-five patients were included in this series. The patients’ mean age was 33 years (range 11-71 years). Eight patients were treated surgically within 2 weeks; while the other 27 patients, with prolonged or recurrent CSF rhinorrhea, received the repair surgery at 17 days to 10 years after the initial trauma. The mean overall length of follow-up was 23 months (range 3-65 months). All the patients suffered from frontobasal multiple fractures. The basic repair tenet was to achieve watertight seal of the dura. The frontal pericranial flap alone was used in 20 patients, combined with temporalis muscle and/or its facia in 10 patients. Free fascia lata graft was used instead in the rest 5 patients. No CSF leak was found in all the patients at discharge. There was no surgical mortality in this series. Bilateral anosmia was the most common complication. At follow-up, no recurrent CSF leak or meningitis occurred. No patients developed mucoceles, epidural abscess or osteomyelitis. One patient ultimately required ventriculoperitoneal shunt because of progressive hydrocephalus. Conclusion: Traumatic CSF rhinorrhea associated with extensive anterior skull base fractures often requires aggressive treatment via extended intracranial extradural approach. Vascularized tissue flaps are ideal grafts for cranial base reconstruction, either alone or in combination with temporalis muscle and its fascia—fascia lata sometimes can be opted as free autologous graft. The approach is usually reserved for patients with traumatic CSF rhinorrhea in complex frontobasal injuries.     

Lumbar cerebrospinal fluid pressure waves versus intracranial pressure waves in idiopathic normal pressure hydrocephalus

The aim of this study was to explore how the lumbar cerebrospinal fluid pressure (CSFP) waves recorded during lumbar infusion compared with the intracranial pressure (ICP) waves recorded, either during lumbar infusion or during long-term, overnight monitoring. For this purpose, we assessed 27 simultaneous lumbar CSFP/ICP recordings made during lumbar infusion and 27 long-term, overnight ICP recordings in 27 consecutive idiopathic normal pressure hydrocephalus (iNPH) patients. Pressure waves during lumbar infusion were explored by computing pulse pressure amplitude and mean single wave pressure of every corresponding CSFP/ICP wave pair; among our 27 lumbar CSFP/ICP recordings a total of 35,532 CSFP/ICP wave pairs were available for analysis. We as well computed mean values of pulse pressure amplitude (i.e. mean CSFP wave amplitude or mean ICP wave amplitude) and mean values of mean single wave pressure (i.e. mean CSFP or mean ICP) during consecutive 6-s time windows, as well as average values for the individual recordings. During lumbar infusion, the cerebrospinal fluid pulse pressure amplitudes were about 2 mmHg smaller than the corresponding intracranial pulse pressure amplitudes. The mean CSFP wave amplitudes recorded during lumbar infusion correlated significantly with the mean ICP wave amplitudes recorded either during lumbar infusion or during long-term, overnight ICP monitoring. In 21 of 27 lumbar infusion tests (78%), the presence of elevated lumbar mean CSFP waves was related to presence of elevated mean ICP wave amplitudes during long-term, overnight ICP monitoring. Hence, the lumbar cerebrospinal fluid pulse pressure amplitudes recorded during lumbar infusion could be used to predict the intracranial pulse pressure amplitudes recorded during long-term, overnight ICP monitoring.