Bilateral sixth cranial nerve palsy after unintentional dural puncture

Unveiling the vulnerability of the human abducens nerve: insights from comparative cranial base anatomy in mammals and primates

The topographic anatomy of the abducens nerve has been the subject of research for more than 150 years. Although its vulnerability was initially attributed to its length, this hypothesis has largely lost prominence. Instead, attention has shifted toward its intricate anatomical relations along the cranial base. Contrary to the extensive anatomical and neurosurgical literature on abducens nerve anatomy in humans, its complex anatomy in other species has received less emphasis. The main question addressed here is why the human abducens nerve is predisposed to injury. Specifically, we aim to perform a comparative analysis of the basicranial pathway of the abducens nerve in mammals and primates. Our hypothesis links its vulnerability to cranial base flexion, particularly around the sphenooccipital synchondrosis. We examined the abducens nerve pathway in various mammals, including primates, humans (N = 40; 60% males; 40% females), and human fetuses (N = 5; 60% males; 40% females). The findings are presented at both the macroscopic and histological levels. To associate our findings with basicranial flexion, we measured the cranial base angles in the species included in this study and compared them to data in the available literature. Our findings show that the primitive state of the abducens nerve pathway follows a nearly flat (unflexed) cranial base from the pontomedullary sulcus to the superior orbital fissure. Only the gulfar segment, where the nerve passes through Dorello's canal, demonstrates some degree of variation. We present evidence indicating that the derived state of the abducens pathway, which is most pronounced in humans from an early stage of development, is characterized by following the significantly more flexed basicranium. Overall, the present study elucidates the evolutionary basis for the vulnerability of the abducens nerve, especially within its gulfar and cavernous segments, which are situated at the main synchondroses between the anterior, middle, and posterior cranial fossae-a unique anatomical relation exclusive to the abducens nerve. The principal differences between the pathways of this nerve and those of other cranial nerves are discussed. The findings suggest that the highly flexed human cranial base plays a pivotal role in the intricate anatomical relations and resulting vulnerability of the abducens nerve.

Evidence-based clinical practice guidelines on postdural puncture headache: a consensus report from a multisociety international working group

INTRODUCTION

Postdural puncture headache (PDPH) can follow unintentional dural puncture during epidural techniques or intentional dural puncture during neuraxial procedures such as a lumbar puncture or spinal anesthesia. Evidence-based guidance on the prevention, diagnosis or management of this condition is, however, currently lacking. This multisociety guidance aims to fill this void and provide practitioners with comprehensive information and patient-centric recommendations to prevent, diagnose and manage patients with PDPH.

METHODS

Based on input from committee members and stakeholders, the committee cochairs developed 10 review questions deemed important for the prevention, diagnosis and management of PDPH. A literature search for each question was performed in MEDLINE (Ovid) on 2 March 2022. The results from each search were imported into separate Covidence projects for deduplication and screening, followed by data extraction. Additional relevant clinical trials, systematic reviews and research studies published through March 2022 were also considered for the development of guidelines and shared with contributors. Each group submitted a structured narrative review along with recommendations graded according to the US Preventative Services Task Force grading of evidence. The interim draft was shared electronically, with each collaborator requested to vote anonymously on each recommendation using two rounds of a modified Delphi approach.

RESULTS

Based on contemporary evidence and consensus, the multidisciplinary panel generated 50 recommendations to provide guidance regarding risk factors, prevention, diagnosis and management of PDPH, along with their strength and certainty of evidence. After two rounds of voting, we achieved a high level of consensus for all statements and recommendations. Several recommendations had moderate-to-low certainty of evidence.

CONCLUSIONS

These clinical practice guidelines for PDPH provide a framework to improve identification, evaluation and delivery of evidence-based care by physicians performing neuraxial procedures to improve the quality of care and align with patients' interests. Uncertainty remains regarding best practice for the majority of management approaches for PDPH due to the paucity of evidence. Additionally, opportunities for future research are identified.

Isolated Abducens Nerve Palsy Following Spinal Anesthesia

A healthy 28-year-old lady, para 1, presented to the emergency department with persistent frontal headache, nausea, and vomiting following an emergency cesarean section four days ago. She experienced difficulties with six failed attempts of spinal anesthesia intrapartum before conversion to general anesthesia. A 25-gauge Whitacre needle was utilized for administering spinal anesthesia under a sitting position. The anesthetist noticed a loss of resistance upon needle insertion, but only a negligible amount of cerebrospinal fluid was obtained upon removing the stylet. The patient underwent an emergency cesarean section due to fetal distress, and she was not in labor during the attempts of spinal anesthesia. Otherwise, the cesarean section lasted for an hour and was uneventful. No intrapartum eclampsia or pre-eclampsia. She was diagnosed with post-dural puncture headache, and her symptoms improved after receiving intravenous hydration, oral caffeine, and non-steroidal anti-inflammatory drug (NSAIDs). However, on the sixth day after the spinal anesthesia, she suddenly developed double vision. Examination showed bilateral visual acuity was measured at 6/7.5. No proptosis or ptosis was noted. The relative afferent pupillary defect was negative with no anisocoria. Both eyes were orthophoria with normal head posture. Extraocular muscles revealed a right abduction restriction of -1 with the patient complaining of binocular horizontal diplopia at the right gaze, consistent with right abducens nerve palsy. Systemic neurological findings were normal, and imaging results were unremarkable. Diagnosis of right abducens nerve palsy post-dural puncture was made clinically. The patient was keen on conservative management instead of blood patch therapy. Hence, she was treated supportively via uni-ocular patching to relieve diplopia. Spontaneous complete recovery of the right abducens nerve palsy was observed after three weeks. Cranial nerve palsy is a rare complication reported following spinal anesthesia, with the abducens nerve being the commonest nerve involved. Although it is not always benign, the presented case showed spontaneous complete recovery of the right abducens nerve palsy after three weeks. Awareness of this uncommon complication will avoid unnecessary distress and investigative burden to both the patient and the doctor.

Magnetic resonance imaging of cerebrospinal fluid spread in the epidural space and postdural puncture headache in obstetrics: A proof-of-concept study

BACKGROUND

Currently, performing an epidural blood patch (EBP) for postdural puncture headache (PDPH) remains a subjective clinical decision. An evidence-based protocol may be of value in identifying women at high risk of developing a severe PDPH.

OBJECTIVE

To investigate a potential correlation between the extent of CSF spread in the epidural space, as noted on Magnetic Resonance Imaging (MRI), and the likelihood of development of severe PDPH in obstetric patients.

DESIGN

A prospective double-blind quasi-observational study.

SETTING

Eight tertiary obstetric units, from NHS hospitals.

PATIENTS

Parturients with accidental dural puncture (ADP) underwent T1 and T2-weighted MRI scans of the brain and lumbar spine within 48 h after delivery. All women were followed up, daily, for 1 week.

MAIN OUTCOME MEASURES

For each woman, a PDPH severity score was calculated using a four-point Verbal Reporting Scale (none = 0, mild = 1, moderate = 2, severe = 3), with additional points awarded for visual, auditory and emetic symptoms. MRIs were reported by a neuroradiologist, blind to the patient details, using a predefined MRI score.

RESULTS

Twenty-two parturients were recruited; 86% (n=19) developed PDPH and 10 of these (53%) required an EBP. The median (range) time for the onset of PDPH was 24 (4 to 126) hours. The median (range) cumulative PDPH severity score was 10 (0 to 21), whereas, the median (range) MRI score was 2.5 (0 to 12). Spearman (rs) analysis identified a significant positive correlation (rs = 0.46; P = 0.024) between cumulative PDPH severity and MRI scores. Of all the radiological features identified in an MRI (lumbar dural shift, caudal brain displacement, epidural or intrathecal blood), the presence of intrathecal blood was most strongly correlated with PDPH severity (P = 0.043).

CONCLUSION

Following an ADP, the extent of CSF spread in the epidural space correlates with the severity of subsequent PDPH.

CLINICAL TRIAL NUMBER AND REGISTRY URL

ISRCTN14959004, https://www.isrctn.com/.

Neurological complications of lumbar and cervical dural punctures with a focus on epidural injections

Background:

Various types of lumbar dural punctures may contribute to neurological injury. The etiologies of dural injury include; inadvertent dural punctures due to epidurals placed for labor anesthesia, epidural steroid injections (ESI/transforaminal TESI; approximately 9 million ESI performed in the US per year), deliberate placement of intradural pain devices, and spontaneous cerebrospinal fluid (CSF) fistulas. Resulting neurological complications may include; spinal headaches/intracranial hypotension, subdural hematomas, and 6^th nerve cranial palsies. Furthermore, uniquely in the cervical spine, inadvertent cervical dural punctures attributed to cervcial ESI (CESI) may lead to intramedullary spinal cord injuries (e.g. resulting in monoparesis to quadriplegia) or spinal cord strokes due to intravascular/vertebral artery injections.

Methods/Results:

In 8 studies, inadvertent lumbar dural punctures contributed to intracranial hypotension, subdural hematomas, and double vision/6^th cranial nerve palsies. In 5 of the 6 studies, inadvertent dural punctures occurring during CESI were responsible for intramedullary spinal cord injuries, or direct intravascular/vertebral injections resulting in monoplegia/quadriplegia.

Conclusions:

Inadvertent lumbar dural punctures led to multiple neurological complications including intracranial hypotension, subdural hematomas, and double vision/6^th cranial nerve palsies. Uniquely, inadvertent cervical dural punctures solely due to CESI directly resulted in intramedullary spinal cord injuries or cord stroked and monoplegia/quadriplegia attributed to intravascular/vertebral artery injections. The potential neurological risks/complications/adverse events attributed to lumbar and cervical ESI must be taken into account before spine surgeons and others order these procedures.

Bilateral Abducent Nerve Palsy After Neck Trauma: A Case Report

INTRODUCTION

The abducent nucleus is located in the upper part of the rhomboid fossa beneath the fourth ventricle in the caudal portion of the pons. The abducent nerve courses from its nucleus, to innervate the lateral rectus muscle. This nerve has the longest subarachnoid course of all the cranial nerves, it is the cranial nerve most vulnerable to trauma. It has been reported that 1% to 2.7% of all head injuries are followed by unilateral abducent palsy, but bilateral abducent nerve palsy is extremely rare.

CASE PRESENTATION

A 65-year-old woman presented to the emergency department following a motor vehicle accident. A neurological assessment showed the patient's Glascow coma scale (GCS) to be 15. She complained of double vision, and we found lateral gaze palsy in both eyes. A hangman fracture type IIA (C2 fracture with posterior ligamentous C1 - C2 distraction) was found on the cervical CT scan. A three-month follow-up of the patient showed complete recovery of the abducent nerve.

CONCLUSIONS

Conservative treatment is usually recommended for traumatic bilateral abducent nerve palsy. Our patient recovered from this condition after three months without any remaining neurological deficit, a very rare outcome in a rare case.

Cranial nerve palsy secondary to cerebrospinal fluid diversion

OBJECTIVE

Cranial nerve palsy (CNP) secondary to cerebrospinal fluid (CSF) diversion is less familiar to us as a result of its rarity in incidence and insidiousness in presentation. This study aims to further expound the pathophysiological mechanism, clinical presentation, diagnosis, management and prognosis of CNP.

METHODS

From June 2012 to February 2015, 5 of 347 consecutive patients with CNPs secondary to different CSF diversion procedures were treated at our institution. A systematic PubMed search of published studies written in English for patients developing CNPs after CSF diversion procedures from January 1950 to June 2015 was conducted.

RESULTS

Overall, 29 studies and 5 patients of the current series totaling 53 CNPs met the inclusion criteria. CN II, III, IV, V, VI, VII and VIII were got involved in 2 (3.8%), 2 (3.8%), 5 (9.4%), 1 (1.9%), 44 (83.0%), 4 (7.5%) and 1 (1.9%) patients respectively. Thirty-eight patients (71.7%) developed CNPs following inadvertent lumbar puncture, 8 (15.1%) following lumbar drainage, and 7 (13.2%) following ventriculoperitoneal shunt. Forty-eight (90.6%) patients got resolved completely.

CONCLUSIONS

The proposed mechanism of CNP after CSF diversion procedure is CSF hypovolemia and subsequent downward displacement of the brain and traction and distortion of the vascular and peripheral neural structures. As a result of its distinct anatomic characteristics rather than long intracranial course, CN VI is most commonly affected. With early recognition and timely conservative management, most patients could get favorable recovery.

Cranial nerve VI palsy after dural-arachnoid puncture

In this article, we provide a literature review of cranial nerve (CN) VI injury after dural-arachnoid puncture. CN VI injury is rare and ranges in severity from diplopia to complete lateral rectus palsy with deviated gaze. The proposed mechanism of injury is cerebrospinal fluid leakage causing intracranial hypotension and downward displacement of the brainstem. This results in traction on CN VI leading to stretch and neural demyelination. Symptoms may present 1 day to 3 weeks after dural-arachnoid puncture and typically are associated with a postdural puncture (spinal) headache. Resolution of symptoms may take weeks to months. Use of small-gauge, noncutting spinal needles may decrease the risk of intracranial hypotension and subsequent CN VI injury. When ocular symptoms are present, early administration of an epidural blood patch may decrease morbidity or prevent progression of ocular symptoms.

Multiple concomitant cranial nerve palsies secondary to preeclampsia

A 32-year-old primigravid woman developed pre-eclampsia after delivery of twins along with left fifth, sixth, and seventh cranial neuropathies. She also had evidence of hepatic and renal involvement. Results of patient evaluation were otherwise unremarkable, and the palsies completely resolved over 3 months after treatment with valacyclovir and systemic corticosteroids.

Major pneumocephalus after lung resection

We present the case of a 62-year-old woman with an advanced metastatic lung tumor that required palliative debulking. Perioperative placement of a surgical clip in the dura of the thoracic spinal cord caused a dural breach, which ultimately caused a pneumocephalus. An awareness of this association is important, especially in patients undergoing thoracic resections. We also describe our approach to the management of this condition.

Why should we use atraumatic needles in lumbar puncture?

Diagnostic lumbar puncture is essential to the diagnosis of central nervous system infections, subarachnoid haemorrhage and others neurological diseases. Myeloradicular involvement or life-threatening adverse events due to the procedure are rare, but less severe complications are more frequent. Post-lumbar puncture headache is the most common complication, by spinal fluid leakage due to delayed closure of a dural defect. Therefore, the development of fine needles, with differentiated atraumatic bevel, has contributed to minimize that problem. These generically called atraumatic needles cause less deformation of the dura mater then the Quincke® ones. So, why don't we use these atraumatic needles?

A case of traumatic bilateral abducens and unilateral hypoglossal nerve palsy

Patient: Female, 47

Final Diagnosis: Traumatic bilateral abducens • unilateral hypoglossal nerve palsy

Symptoms: Diplopia

Medication: —

Clinical Procedure: —

Specialty: Neurology

Objective: Rare disease

Post-dural (post-lumbar) puncture headache: risk factors and clinical features

OBJECTIVE

This is an analytic, interventional, cross sectional study to evaluate the risk factors of post-dural (post-lumbar) puncture headache (PDPH) and the validity of the diagnostic criteria for PDPH from the ICHD II.

METHODS

Six-hundred-and-forty patients (332 non-pregnant women and 308 men) aged 8-65 years underwent spinal anesthesia with Quincke 25G or 27G needles in elective surgery.

RESULTS

Forty-eight (7.5%) of the patients developed PDPH. The binary logistic regression analysis identified as risk factors: gender [11.1% female vs. 3.6% male, OR 2.25 (1.07-4.73); p = 0.03], age [11.0% 31-50 years of age vs. 4.2% others, OR 2.21 (1.12-4.36); p = 0.02], previous history of PDPH [26.4% positive vs. 6.2% negative, OR 4.30 (1.99-9.31); p < 0.01] and bevel orientation [16.1% perpendicular vs. 5.7% parallel, OR 2.16 (1.07-4.35); p = 0.03]. The period of latency between lumbar puncture and headache onset range from 6 to 72 hours and the duration from 3 to 15 days. In 34/48 (71%) patients with PDPH, at least one of the following was present: neck stiffness, tinnitus, hypoacusia, photophobia, or nausea.

CONCLUSION

In conclusion, 14/48 patients (29%) suffered none of the above-mentioned symptoms, indicating that a significant number of patients may suffer from PDPH in the absence of any symptoms apart from the headache itself. This suggests that a further analyses of existing studies should be made to determine if a criteria change may need consideration.

Delayed bilateral abducens nerve palsy after head trauma

Although the incidence of unilateral abducens nerve palsy has been reported to be as high as 1% to 2.7% of head trauma cases, bilateral abducens nerve palsy following trauma is extremely rare. In this report, we present the case of a patient who developed a bilateral abducens nerve palsy and hypoglossal nerve palsy 3 days after suffering head trauma. He had a Glasgow Coma Score (GCS) of 15 points. Computed tomography (CT) images demonstrated clivus epidural hematoma and subarachnoid hemorrhage on the basal cistern. Herein, we discuss the possible mechanisms of these nerve palsies and its management.

[Complications after regional anesthesia]

In recent years, there has been a considerable increase in the number of procedures carried out under regional anesthesia. The techniques used can be associated with a number of complications, which should be understood so that they can be recognized and managed appropriately. The overall incidence of reported complications associated with these techniques is low and therefore, with currently available data, we can only have an approximate idea of their incidence. The objective of this study is to systematically describe the complications that may arise from the use of neuraxial and peripheral regional anesthesia techniques.

To replace or not to replace? - Partial coning and a sixth nerve palsy secondary due to displacement of a tunnelled intrathecal catheter for pain control

We report the displacement of a tunnelled intrathecal catheter causing significant cerebrospinal fluid (CSF) leak, resulting in partial coning and a sixth nerve palsy. The patient had advanced malignant mesothelioma and all other methods of pain control had been unsuccessful. As far as we are aware, there are no published reports of early replacement of an intrathecal catheter in patients with neurological sequelae. Surgical re-siting of the intrathecal catheter produced good pain relief for many months. Doctors involved in the use of indwelling intrathecal catheters for pain control must be aware of the risk of significant neurological sequelae but should not dismiss re-establishment of intrathecal therapy in the presence of significant neurological complications.

Case report: Epidural blood patch in the treatment of abducens palsy after a dural puncture

PURPOSE

To describe a case of iatrogenically induced abducens nerve palsy following a diagnostic lumbar puncture, and to review the evidence for blood patching in the management of sixth cranial nerve palsy after dural puncture.

CLINICAL FEATURES

A 45-yr-old woman developed post-dural puncture headache with bilateral abducens palsy following a diagnostic lumbar puncture. Magnetic resonance imaging showed findings compatible with intracranial hypotension. An epidural blood patch was performed five days after the onset of diplopia and ten days following the dural puncture. After blood patching, the patient reported relief of the headache, but still complained of diplopia. The palsies recovered spontaneously 21 months after the dural puncture.

CONCLUSION

Experience from this case as well as other case report evidence suggest that an epidural blood patch performed more than 24 hr after the onset of a sixth cranial nerve palsy consistently fails to relieve diplopia. An epidural blood patch executed within 24 hr from the onset of diplopia could possibly lead to partial improvement and/or earlier resolution of symptoms.

Postdural puncture headache

PURPOSE OF REVIEW

Postdural puncture headache remains the most frequent complication of neuraxial anesthesia. It can occur following uncomplicated spinal anesthesia as well as unintended dural puncture during epidural anesthesia.

RECENT FINDINGS

The incidence following accidental dural puncture is not as high as previously thought--approximately 50%. There are not many maneuvers that prevent postdural puncture headache. The most promising is an intrathecal catheter as it avoids further dural puncture and seals the hole during the time it is in place, decreasing cerebrospinal fluid loss. Several means to treat a postdural puncture headache exist. Medications that increase cerebral vascular resistance are the ones advocated. Methergine (methylergonovine maleate) has been advocated for postdural puncture headache following spinal anesthesia; it has not been studied for accidental dural puncture with a large bore needle. Epidural blood patch remains the treatment of choice.

SUMMARY

An epidural blood patch should not be performed until 24 h after dural puncture to increase its success; however, it should not be delayed beyond that period in the symptomatic patient, as this delay increases the amount of time the patient suffers.