A challenging case of sporadic melanocytoma of the jugular foramen.

BACKGROUND: The jugular foramen (JF) can be the site of several tumours. Paragangliomas, schwannomas and meningiomas are the most commonly reported. We describe a case of melanocytoma originating from the JF and presenting with an accessory nerve palsy. ILLUSTRATIVE CASE: A 48-year-old woman presented with a 6-month history of cervical and left shoulder pain with wasting and weakness of the left trapezius. A Magnetic Resonance Imaging (MRI) showed a T1-hyperintense, T2-isointense, heterogeneously enhancing lesion involving the left JF and extending into the cerebello-medullary and cerebello-pontine cisterns. A retrosigmoid craniotomy was performed and a near-total removal achieved. The accessory nerve was involved by tumour and could not be preserved. Given the diagnostic uncertainty between melanotic schwannoma, metastatic melanoma and meningeal melanocytoma, next generation sequencing and genome-wide DNA methylation arrays were performed, documenting a mutation in GNA11 (c.6226A>T, p. Gln209Leu) and a methylation profile consistent with melanocytoma. The patient underwent adjuvant fractionated radiotherapy of the tumour remnant. A follow-up MRI 4 years after surgery did not show any tumour recurrence. CONCLUSIONS: The differential diagnosis of skull base pigmented tumours can be challenging, particularly when they occur in unusual locations such as the JF. They can be misdiagnosed given their similar clinical, neuroradiological and pathological features if anatomy of the site of origin is not carefully considered and molecular tests are not performed, leading to erroneous treatment and follow-up planning.

Successful conservative treatment of an intracranial pneumatocele with post-traumatic hypoglossal nerve palsy secondary to diffuse temporal bone pneumocele: case report and review of the literature.

BACKGROUND: A pneumocele occurs when an aerated cranial cavity pathologically expands; a pneumatocele occurs when air extends from an aerated cavity into adjacent soft tissues forming a secondary cavity. Both pathologies are extremely rare with relation to the mastoid. This paper describes a case of a mastoid pneumocele that caused hypoglossal nerve palsy and an intracranial pneumatocele. CASE REPORT: A 46-year-old man presented, following minor head trauma, with hypoglossal nerve palsy secondary to a fracture through the hypoglossal canal. The fracture occurred as a result of a diffuse temporal bone pneumocele involving bone on both sides of the hypoglossal canal. Further slow expansion of the mastoid pneumocele led to a secondary middle fossa pneumatocele. The patient refused treatment and so has been managed conservatively for more than five years, and he remains well. CONCLUSION: While most patients with otogenic pneumatoceles have presented acutely in extremis secondary to tension pneumocephalus, our patient has remained largely asymptomatic. Aetiology, clinical features and management options of temporal bone pneumoceles and otogenic pneumatoceles are reviewed.

Adrenalectomy reduces adiposity by decreasing food efficiency, not direct effects on white adipose tissue.

OBJECTIVE: This study was conducted to establish the effects of adrenalectomy (ADX) on adipose tissue metabolism in male Sprague-Dawley rats fed a standard chow diet. RESEARCH METHODS AND PROCEDURES: The effects of adrenalectomy on adipose cell size, lipoprotein lipase activity, and basal and insulin-stimulated glucose conversion to lipid and lipolysis were measured. RESULTS: ADX decreased body weight gain during the post-operative period in the absence of changes in food intake; feed efficiency was decreased significantly. ADX decreased adipocyte size by 30%. ADX increased adipocyte response to the effect of submaximal concentrations of insulin on lipid synthesis and lipolysis. ADX decreased maximally insulin-stimulated lipid synthesis, but this effect was accounted for by decreased adipocyte size. In contrast, ADX had no effect on maximally insulin-inhibited lipolysis. ADX did not affect heparin-releasable LPL. The small effect of ADX on residual extractable adipose tissue LPL activity was accounted for by decreased fat cell size. DISCUSSION: ADX decreased adiposity in the absence of changes in food intake, lipoprotein lipase activity, and adipocyte lipid metabolism. The effect is best attributed to decreased feed efficiency.

Insulin affects dopamine overflow in the nucleus accumbens and the striatum.

To better characterize the central nervous system response to peripheral insulin administration, male Sprague-Dawley rats were fitted with microdialysis probes in the nucleus accumbens (NAC; n = 23) and striatum (STR; n = 22). Awake intact rats were injected with either 0, 200, 400, or 600 mU regular insulin i.p. Dopamine overflow was measured for at least 2 h postinjection. In the NAC, four postinjection samples were collected once every 30 min. In the STR, eight postinjection samples were collected, once every 20 min. Dopamine baselines in the NAC and STR were 9.22 pg +/- 2.02 and 10.33 pg +/- 2.22 per sample, respectively. In the nucleus accumbens, dopamine release was significantly greater in the group treated with 600 mU insulin (203 +/- 38% of baseline at 30 min). In the STR, increased dopamine release was observed in the groups treated with 200 and 400 mU insulin, whereas a suppression of a dopamine release was observed in the group treated with 600 mU. These data demonstrate that the metabolic state induced by peripheral insulin injection causes dopamine metabolism to change in both the NAC and STR, and at least in part support the hypothesis that insulin may have reinforcing properties in its effect on NAC dopamine release.