Spinal arteriovenous malformation in a pediatric patient with a history of congenital syphilis: a case report.

BACKGROUND: Spinal arteriovenous malformations in children are extremely rare and pose great risk for intraoperative hemorrhage. Congenital syphilis sometimes presents with vascular symptoms, however, there is little published on patients with a history of congenital syphilis presenting with spinal arteriovenous malformations. CASE PRESENTATION: A 15-month-old female with a history of congenital syphilis presented with urinary retention, fever, and subacute onset of paraplegia. MRI showed a lesion at T8-L1, angiogram was performed which confirmed the presence of a complex type IVc arteriovenous malformation and fistula from Artery of Adamkiewicz at L1-L2. It also showed peri medullary dilated veins and a pseudoaneurysm that compressed the spinal cord at T8-T10. Somatosensory evoked potentials and motor-evoked potentials were not recordable on the bilateral lower extremities prior to surgery. Once the patient was optimized for surgery, osteoplastic laminotomies from T6-T12 were performed. The dura was opened and the intradural, intramesenchymal hematoma was evacuated. There were two episodes of brisk arterial bleeding with hypotension during resection of the hematoma. The patient was taken to the angiography suite from the OR to successfully coil the large aneurysm. Intraoperative spinal cord monitoring remained undetectable in the bilateral lower extremities. The patient's paraplegia remained unchanged from preoperative presentation. CONCLUSION: Congenital syphilis may present with vascular changes that might impact surgical approaches and treatment outcomes in patients with spinal arteriovenous malformations. Preparation for massive transfusion and intraoperative monitoring are imperative in ensuring a safe perioperative experience.

A prediction of postoperative neurological deficits following intracranial aneurysm surgery using somatosensory evoked potential deterioration duration.

Although the application of somatosensory evoked potential (SSEP) in intracranial aneurysm surgery has been well demonstrated, the relationship between the duration of SSEP deterioration and postoperative neurological deficits (PNDs) is still not clear. The objectives of this study were (1) to detect the relationship between the SSEP deterioration duration and PND; and (2) detect the relationship between SSEP deterioration duration and postoperative computed tomography (CT) findings. Data from 587 patients were reviewed and 40 patients with SSEP deterioration were enrolled. Four patients presented irreversible disappearance and 36 patients presented reversible deterioration (including 9 [25%] patients with reversible reduction and 27 [75%] patients with reversible disappearance). In the patients with reversible SSEP deterioration, 17 patients had PNDs, and the SSEP deterioration duration was 42 ± 46 min, ranging from 5 to 180 min. Nineteen patients did not have PNDs, and their duration of SSEP deterioration was 11 ± 9 min (range 2-40 min). The SSEP deterioration duration significantly differed between patients with or without PND (P < 0.01). Eleven minutes is the optimal cut-off value of motor evoked potential change duration avoiding PND (area under the curve = 0.84). Patients with a SSEP deteriorating duration > 11 min had a significant higher incidence rate of abnormal CT finding postoperatively (p < 0.05). According to these results, we conclude that the duration of SSEP deterioration is extremely important to postoperative neurological function, and in order to avoid PND, the SSEP deterioration duration must not exceed 10 min. The SSEP deterioration duration is also associated with postoperative CT findings.

Somatosensory evoked potentials help prevent positioning-related brachial plexus injury during skull base surgery.

OBJECTIVE: Evaluate the use of somatosensory evoked potentials (SSEP) monitoring to detect positioning-related brachial plexus injury during skull base surgery. STUDY DESIGN: Prospective cohort observational study. SETTING: University Hospital. SUBJECTS AND METHODS: Patients undergoing skull base surgery had a focused neurologic exam of the brachial plexus performed before and after surgery. Under stable anesthesia, brachial plexus SSEP values were obtained before and after surgical positioning. Significant SSEP changes required a readjustment of arm or neck positions. SSEPs were assessed every 30 minutes. If changes were noted, position was readjusted and SSEPs were reassessed until surgical completion. Demographic data, neurologic exams, SSEP latency, and amplitude values were recorded. Persistent changes were correlated with postoperative neurologic findings. RESULTS: Sixty-five patients, 15 to 77 years old, were studied. Six patients (9.2%) developed SSEP amplitude changes after positioning (average amplitude decrease 72.8%). One patient had a significant latency increase. The sensitivity of SSEP for detection of injury was 57%, while specificity was 94.7%. The average body mass index (BMI) of patients with normal and abnormal SSEPs was 28.7 ± 5.6 versus 29.2 ± 8.0, respectively. Average BMI of patients with postoperative symptoms regardless of SSEP findings was 33.8 ± 4.3. Two patients who had persistent SSEP changes after positioning had BMIs of 40.1 and 31.2 kg/m(2), respectively. Improvement in neurologic findings occurred in all patients after surgery. CONCLUSIONS: This study demonstrates that upper extremity nerve stress can be detected in real time using SSEP and may be of value in protecting patients from nerve injury undergoing lateral skull base surgery.