Variability in the diagnostic and management practices of post-hemorrhagic ventricular dilatation in very preterm infants across Canadian centers and comparison with European practices.

OBJECTIVES: To investigate the variability in diagnostic and therapeutic approaches to posthemorrhagic ventricular dilatation (PHVD) among Canadian neonatal centers, and secondary exploration of differences in approaches between Canadian and European practices. METHODS: We conducted a survey among Canadian tertiary neonatal centers on their local practices for managing very preterm infants with PHVD. The survey covered questions on the diagnostic criteria, timing and type of interventions and resources utilization (transfer to neurosurgical sites and neurodevelopmental follow-up). In a secondary exploration, Canadian responses were compared with responses to the same survey from European centers. RESULTS: 23/30 Canadian centers (77%) completed the survey. There was no consensus among Canadian centers on the criteria used for diagnosing PHVD or to initiate intervention. The therapeutic interventions also vary, both for temporizing procedures or permanent shunting. Compared to European practices, the Canadian approach relied less on the sole use of ultrasound criteria for diagnosing PHVD (43 vs 94%, p < 0.0001) or timing intervention (26 vs 63%, p = 0.007). Majority of European centers intervened early in the development of PHVD based on ultrasound parameters, whereas Canadian centers intervened based on clinical hydrocephalus, with fewer centers performing serial lumbar punctures prior to neurosurgical procedures (40 vs 81%, p = 0.003). CONCLUSION: Considerable variability exists in diagnosis and management of PHVD in preterm infants among Canadian tertiary centers and between Canadian and European practices. Given the potential implications of the inter-center practice variability on the short- and long-term outcomes of preterm infants with PHVD, efforts towards evidence-based Canada-wide practice standardization are underway.

Subdural hematomas in infants with benign enlargement of the subarachnoid spaces are not pathognomonic for child abuse.

BACKGROUND AND PURPOSE: Patients who have benign enlargement of the subarachnoid spaces (BESS) have long been suspected of having an increased propensity for subdural hematomas either spontaneously or as a result of accidental injury. Subdural hematomas in infants are often equated with nonaccidental trauma (NAT). A better understanding of the clinical and imaging characteristics of subdural hematomas that occur either spontaneously or as a result of accidental trauma may help distinguish this group of patients from those who suffer subdural hematomas as a result of NAT. The purpose of this study is to describe the clinical and imaging characteristics of subdural hematomas that occur either spontaneously or as a result of accidental injury in infants with BESS. METHODS: We conducted a retrospective review of all patients with BESS complicated by subdural hematomas evaluated at a single institution from 1998 to 2004. Data concerning the patient's clinical presentation, physical findings, imaging, and management are described. RESULTS: During the study period, 7 patients with BESS complicated by subdural hematoma were identified. Their mean age at identification of the subdural hematoma was 7.4 months of age. In 5 cases, there was no recognized trauma before identification of the subdural hematoma. In 3 cases, baseline CT or MR imaging was available, showing prominent subarachnoid spaces without any evidence of subdural hemorrhage. CONCLUSION: Although suspicious for NAT, subdural hematomas can occur in children either spontaneously or as a result of accidental trauma. Caution must be exercised when investigating for NAT based on the sole presence of subdural hematomas, especially in children who are otherwise well and who have BESS.

Spinal hamartoma in a neonate: Unusual presentation and MR imaging findings.

We report an extremely rare case of a congenital spinal cord hamartoma in a male neonate who presented with upper extremity weakness and a port wine stain on the right upper extremity and chest. MR imaging findings are described, and the importance of localizing the lesion in the spinal canal with respect to the dura and its impact on neurosurgical management is stressed.

Pineal apoplexy: is it a facilitator for the development of pineal cysts?

BACKGROUND: The radiographic identification of pineal cysts has increased dramatically within the last two decades due to the advent of magnetic resonance imaging. Pineal cysts are often found incidentally with only a minority of these lesions ever becoming symptomatic and requiring treatment. Many theories attempting to explain the pathogenesis of these cysts exist. METHODS: We describe a case of a 12-year-old girl who presents with a pineal hemorrhage of unknown etiology with associated hydrocephalus. RESULTS: Her hydrocephalus was initially treated with an external ventricular drain followed by a third ventriculostomy. She had no evidence of elevated beta human chorionic gonadotropin or alpha-fetoprotein within the serum or cerebrospinal fluid. Follow-up imaging at seven weeks revealed resolution of her hemorrhage, however, there was development of a progressive cystic lesion within the pineal region. In order to make a definitive tissue diagnosis, a supracerebellar infratentorial surgical approach with complete resection was performed. During the resection, brownish fluid was aspirated from the cyst and the cyst wall was removed. The pathological diagnosis was a pineal cyst. CONCLUSIONS: Although cases have been described of pineal apoplexy with an underlying cyst, this case describes the development of a progressive pineal cyst secondary to a hemorrhage. This case demonstrates that pineal hemorrhage may be a promotor for the development or progression of pineal cysts.

Endovascular treatment of a "blister-like" aneurysm of the internal carotid artery.

BACKGROUND: "Blister-like" aneurysms of the supraclinoid internal carotid artery have recently been recognized as having unique pathological and clinical features. Little is known regarding their optimal treatment modality. METHODS: We report a case of a "blister-like" aneurysm of the internal carotid artery treated with Guglielmi detachable coil (GDC) embolization. CASE REPORT: A 55-year-old man presented with a Hunt & Hess grade II subarachnoid hemorrhage. Computed tomography revealed diffuse subarachnoid blood. Cerebral angiography demonstrated a broad-based bulge on the medial wall of the right distal internal carotid artery. The patient was taken to the operating room and underwent a right pterional craniotomy and wrapping of this unclippable aneurysm. On postoperative day 11, he developed signs of vasospasm, and repeat angiography showed remarkable growth of the aneurysm. The aneurysm was believed to be amenable to endovascular therapy and was treated by GDC embolization. The patient recovered well and remained neurologically intact on follow-up examinations. Repeat cerebral angiography was performed three and nine months following his initial presentation and revealed a significant aneurysm neck remnant. This neck remnant was treated by repeat GDC embolization 13 months following his subarachnoid hemorrhage. CONCLUSIONS: "Blister-like" aneurysms of the internal carotid artery are important to recognize and are difficult to manage using traditional surgical approaches. Early repeated cerebral angiography is indicated and, where appropriate, endovascular therapy should be considered in the management of these patients.

Deciding about mechanical ventilation in end-stage chronic obstructive pulmonary disease: how respirologists perceive their role.

OBJECTIVE: To determine when respirologists approach patients with end-stage chronic obstructive pulmonary disease (COPD) to decide about the use of mechanical ventilation, what information they provide to patients and how they provide it. DESIGN: Self-administered national survey. PARTICIPANTS: All Canadian specialists in respiratory medicine; of 401 eligible respirologists, 279 (69.6%) returned a completed questionnaire. OUTCOME MEASURES: Timing and content of doctor-patient discussions regarding mechanical ventilation; physicians' perception of their level of involvement in the decision-making process; and patient and physician characteristics that may influence decisions. RESULTS: Discussions were reported to occur most often at advanced stages of COPD: when the patient's dyspnea was severe (reported by 235 [84.2%] of the respondents) or when the patient's forced expiratory volume in the first second was 30% or less than predicted value (reported by 210 [75.3%]). A total of 120 respondents (43.0%) stated that they discuss mechanical ventilation with 40% or less of their COPD patients before an exacerbation necessitates ventilatory support. Most (154 [55.2%]) described the decision-making process as a collaboration between patient and physician; 83 (29.7%) reported that the patient decides after he or she has considered the physician's opinion. Over half (148 [53.0%]) of the respondents indicated that they occasionally, often or always modify the information provided to patients in order to influence their decision about mechanical ventilation. CONCLUSIONS: Discussions with COPD patients concerning end-of-life decisions about mechanical ventilation are reported to occur in advanced stages of the disease or not at all, with patients' input where possible. Information presented to patients is often modified in order to influence the decision. Future studies should explore ways to involve patients further in the decision-making process and to improve the process for both patients and physicians.

What do physicians tell patients with end-stage COPD about intubation and mechanical ventilation?

BACKGROUND: At some point in time, many patients with end-stage COPD require intubation and mechanical ventilation (MV) to sustain life. MV decisions are most effective when the patient and physician have discussed the options in advance. The purpose of this study was to examine how the physician perceives the decision-making process. METHODS: Fifteen respirologists were interviewed to elicit information regarding intubation and MV, and the exchange of information between patients and physicians. Emergent themes were coded using a qualitative approach and were verified by a blinded researcher. RESULTS: Respondents included ten academic and five community-based respirologists from seven hospitals. Most physicians were men with between 4 and 37 years experience. Narratives were very similar in content and seemed well rehearsed. Approach and delivery, however, were unique to each physician. Fourteen respirologists emphasized the importance of knowing patients as individuals prior to initiating this discussion. This period of familiarization often dictated when the physician believed the ventilation discussion is appropriate. Individual physician comfort also appeared to affect the timing of the discussion. Physicians discussed the many elements that make the MV discussion difficult for physicians and patients. Intubation details included a tube being placed down the throat, the discomfort associated with the tube, the inability to speak, and the availability of pain reducing medication. All physicians discussed the possibility of death with their patients, although many preferred euphemisms in initial discussions. All physicians indicated that intubation is presented as the patient's choice. However, all but one physician commonly framed their discussions in order to influence patient choice. The positive or negative framing seemed contingent on the physician's expectations for that patient. CONCLUSIONS: Our interviews demonstrated considerable agreement between physicians about the content and timing of the intubation MV discussion. Physicians all agreed that knowing the patient and his or her situation was important in determining the timing of the intubation and MV discussion. Practice style and individual physician comfort with end-of-life decisions may influence the timing of the discussion and possibly the number of patients who are finally approached. All physicians advocated a shared decision-making approach, but they strongly influence the deliberation process. Thus, the decision-making model seemed to be physician driven in this study.

Identification and characterization of conserved and variable regions in the envelope gene of HTLV-III/LAV, the retrovirus of AIDS.

To determine the extent and nature of genetic variation present in independent isolates of HTLV-III/LAV, the nucleotide sequences of the entire envelope gene and parts of gag and pol were determined for two AIDS viruses. The results indicated that variation throughout the viral genome is extensive and that the envelope gene in particular is most highly variable. Within the envelope, changes were most prevalent within the extracellular region where clustered nucleotide substitutions and deletions/insertions were evident. Based on predicted secondary protein structure and hydrophilicity, these hypervariable regions represent potential antigenic sites. In contrast to the hypervariable regions, other sequences in the extracellular envelope and the overall envelope structure (including 18 of 18 cysteine residues), as well as most of the transmembrane region, were highly conserved.

Vasopressin-induced motor disturbances: localization of a sensitive forebrain site in the rat.

Arginine-vasopressin (AVP) microinjected into an area extending from the diagonal band of Broca to the anterior hypothalamus of the rat evokes severe motor disturbances, including barrel rotations and myoclonic/myotonic movements. These disturbances do not occur after administration of an artificial physiological solution or of oxytocin. Injection of this peptide into other areas of the brain does not cause these effects. This action of vasopressin is dose-related, can be prevented by the prior administration of an AVP receptor antagonist and involves a 'sensitization' process. It is possible that AVP, acting in this mediobasal region of the forebrain, might be involved as a causative agent in some convulsive disorders.