A neurostructural biomarker of dissociative amnesia: a hippocampal study in dissociative identity disorder.

BACKGROUND: Little is known about the neural correlates of dissociative amnesia, a transdiagnostic symptom mostly present in the dissociative disorders and core characteristic of dissociative identity disorder (DID). Given the vital role of the hippocampus in memory, a prime candidate for investigation is whether total and/or subfield hippocampal volume can serve as biological markers of dissociative amnesia. METHODS: A total of 75 women, 32 with DID and 43 matched healthy controls (HC), underwent structural magnetic resonance imaging (MRI). Using Freesurfer (version 6.0), volumes were extracted for bilateral global hippocampus, cornu ammonis (CA) 1-4, the granule cell molecular layer of the dentate gyrus (GC-ML-DG), fimbria, hippocampal-amygdaloid transition area (HATA), parasubiculum, presubiculum and subiculum. Analyses of covariance showed volumetric differences between DID and HC. Partial correlations exhibited relationships between the three factors of the dissociative experience scale scores (dissociative amnesia, absorption, depersonalisation/derealisation) and traumatisation measures with hippocampal global and subfield volumes. RESULTS: Hippocampal volumes were found to be smaller in DID as compared with HC in bilateral global hippocampus and bilateral CA1, right CA4, right GC-ML-DG, and left presubiculum. Dissociative amnesia was the only dissociative symptom that correlated uniquely and significantly with reduced bilateral hippocampal CA1 subfield volumes. Regarding traumatisation, only emotional neglect correlated negatively with bilateral global hippocampus, bilateral CA1, CA4 and GC-ML-DG, and right CA3. CONCLUSION: We propose decreased CA1 volume as a biomarker for dissociative amnesia. We also propose that traumatisation, specifically emotional neglect, is interlinked with dissociative amnesia in having a detrimental effect on hippocampal volume.

Spinal Ependymoma Identified Following Spinal Anesthesia for Cesarean Delivery.

Neuraxial anesthesia is preferred over general anesthesia for cesarean delivery when appropriate because the latter is associated with a higher incidence of airway complications and an increased need for neonatal resuscitation. Common complications of neuraxial anesthesia include backache and headache, whereas feared but rare complications include paraplegia, intraspinal hemorrhage, cauda equina syndrome, nerve injury, and epidural hematoma. This case report presents a 40-year-old female with undiagnosed and asymptomatic ependymoma who presented with concerning neurological symptoms after receiving spinal anesthesia for elective cesarean delivery. Stat lumbar and thoracic spine magnetic resonance imaging (MRI) were performed on postoperative day 13 and were suggestive of a large hypervascular mass with areas of hemorrhage, concerning for ependymoma. An emergent laminectomy and mass resection were performed, resulting in an improvement in the patient's neurological symptoms.

Surgical anesthesia for revision total hip arthroplasty with quadratus lumborum and fascia iliaca block.

We present a case in which surgical anesthesia was provided for revision of earlier total hip arthroplasty with quadratus lumborum and fascia iliaca blocks. We believe that this case is the first to be reported using this technique for this procedure. Our patient was a high-risk candidate for general and neuraxial anesthesia because of significant cardiac dysfunction and therapeutic anticoagulation.

Early Presence of HIV-1 Subtype C in Washington, D.C.

The presence of non-B HIV subtypes in the USA has been documented during the epidemic, although the timing of early introductions of different subtypes remains uncertain. Subtype C, the most common HIV variant worldwide, was first reported in the USA in 1996-97, after subtype C had expanded greatly in sub-Saharan Africa. In this study, we report a patient with subtype C infection acquired by mother-to-child transmission, born in the USA in 1990 to a Washington, D.C. resident who never traveled outside the USA, demonstrating that subtype C was present in the USA much earlier. Comparative analysis of the sequence from this patient and subtype C sequences in the USA and elsewhere suggest multiple independent introductions of this subtype into the USA have taken place, many of which are traced to sub-Saharan or East Africa. These data indicate subtype C HIV was already present in the USA years earlier than previously reported, and during the early period of subtype C expansion.