Enophthalmos and upper eyelid retraction following osteoplastic frontal sinusotomy

A 38-year-old man presented with hyperophthalmia, enophthalmos, and upper eyelid retraction 18 months following an osteoplastic flap and frontal sinus obliteration for mucocele. Computerized tomography confirmed the presence of frontal bone absorption in the roof of the orbit with traction and elevation of the orbital contents into the obliterated frontal sinus. A fracture of the orbital roof with penetration of periorbita at the time of original surgery was the suspected precipitating cause of the complication. Surgical management included lysis of the cicatrix between the orbit and frontal sinus and interposition of a silicone sheet between the orbit and sinus, which restored the appropriate anatomic relationships and prevented recurrence.     

The changing face of reoperative parathyroidectomy: a single-centre comparison of 147 parathyroid reoperations

IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.     

Differential cotransmission in sympathetic nerves: role of frequency of stimulation and prejunctional autoreceptors.

Recent reports have suggested that sympathetic nerves may store separately and release independently the cotransmitters ATP and norepinephrine (NE). It is conceivable therefore that the quantity of each neurotransmitter that is released from the nerves is not fixed but rather may vary, possibly with the frequency of stimulation. To test this hypothesis we studied the concomitant release at various frequencies and cooperative postjunctional actions of ATP and NE during the first 10 s of electrical field stimulation of the guinea pig vas deferens. We found that at lower frequencies (8 Hz), prejunctional inhibition of the release of NE, which occurs via alpha2-adrenoceptors, modulates the ultimate composition of the cocktail of cotransmitters by limiting the amount of NE that is coreleased with ATP. As the frequency of stimulation increases (above 8 Hz), the autoinhibition of the release of NE is overridden and the amount of NE relative to ATP increases. The smooth muscle of the guinea pig vas deferens reacts to changes in composition of the sympathetic neurochemical messages by increasing the amplitude of its contractions due to the enhancement by NE of the contractile responses triggered by ATP. This evidence suggests that the prejunctional alpha2-adrenoceptor may function as a sensor that "reads" the frequency of action potentials produced during a burst of neuronal activity and converts that information into discrete neurochemical messages with varying proportions of cotransmitters. The mechanism for decoding the informational content of these messages is based on the cooperative postjunctional interactions of the participating cotransmitters.     

Lung bullae and pulmonary fibrosis associated with marijuana smoking

A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.