Dorsal Preservation Rhinoplasty: A Literature Review

Acceptance of the preservation principle in rhinoplasty surgery has increased dramatically, and surgeons worldwide are now performing preservation rhinoplasty, leading to an expanding list of indications and techniques. Rhinoplasty surgeons are increasingly opting for rhinoplasty preservation because of its conservative approach and more predictable outcome. This review aims to evaluate the efficacy of dorsal preservation rhinoplasty, as well as the techniques, indications, surgical protocols, complications, and any practical challenges associated with this type of rhinoplasty. A number of medical databases, including Medline-PubMed, Embase, and Scopus, were searched. These searches were supplemented with a manual search using the keyword “preservation rhinoplasty” (PR) during the 1970 to May 2020 time span. The search strategy was limited to case reports, randomized clinical trials, and prospective studies of preservation dorsal rhinoplasty in journals published in English. A total of 150 articles that incorporated preservation dorsal rhinoplasty as a newer surgical technique were reviewed: 136 from PubMed, 17 experimental studies from Embase, 17 clinical studies from Scopus, and 8 studies identified by data extraction. Preservation rhinoplasty represents a paradigm shift in rhinoplasty philosophy. While techniques continue to improve, the philosophy remains the same: preserving and reshaping the existing nasal structures. Although not all patients benefit from and are satisfied with PR and some may only benefit from partial PR, preserving the anatomy allows for a more intuitive operation and natural results. For a more exhaustive review, readers are encouraged to turn their attention to dorsal preservation as a versatile and adaptable technique. Dorsal preservation avoids long-term issues with the middle vault and keystone area, and the patient benefits from total preservation, as the underlying structure can be reshaped without disruption.

Successful Clipping of a Giant Anterior Inferior Cerebellar Artery Aneurysm with Combined Transpetrosal Approach

Background. The anterior inferior cerebellar artery (AICA) aneurysms are rare lesions whose treatment can be challenging. There are only a few previous reports of surgical treatment for such lesions. Objectives. We present a case of a basilar-AICA aneurysm undergoing surgery with the combined transpetrosal approach. Case Description. A 58-year-old female patient presented clinical signs including headache, diplopia, and right hemiparesis. The radiological imaging showed a basilar-AICA aneurysm measuring 25 × 19 mm. The patient was operated via left combined transpetrosal approach. The outcome was graded mRankin 1. Follow-up computerized tomographic angiography showed no aneurysmal residual and total preservation of basilar artery. Discussions. Surgical indication’s purposes were aneurysmal elimination and reduction of mass effect. Combined transpetrosal approach: proximal segment control and enough space for clipping manipulation. Clipping techniques: Temporary clip for aneurysmal collapsing, “orienting clip”. Conclusion. Giant basilar-AICA aneurysm is very rare lesion. Combined transpetrosal approach is appropriate for surgical clipping. Good surgical outcome is achieved with complete elimination of aneurysm.

Formal Addition of Acetone to Unactivated Michael Acceptors via Ring-Opening and Retro-Claisen Fragmentation of Dihydropyranones

<div><div><div><p>We present a general protocol for the formal Michael addition of acetone to a,b-unsaturated esters and amides, a transformation difficult to perform using current methods. The protocol comprises of an amidine catalyzed relay ring-opening and fragmentation of 3,4-dihydropyranones. The reaction proceeds under mild conditions, has a broad substrate scope and the products can be isolated in good to excellent yields (30 examples, with up to 97 % yield). The method can be applied to homochiral substrates with total preservation of chiral information, generating products in high optical purity. Kinetic experiments upported by quantum chemical modeling indicates that the reaction is of second order with respect to the catalyst. The kinetic isotope effect has been determined to be 2.3, which supports a mechanism in which the catalyst takes a bifunctional role, acting both as a Brønsted base and as a hydrogen bond donor. The findings presented here enables a rapid entry to compounds previously considered difficult to access and highlights the dual functionality of amidine superbases as catalysts.</p></div></div></div>

Formal Addition of Acetone to Unactivated Michael Acceptors via Ring-Opening and Retro-Claisen Fragmentation of Dihydropyranones

<div><div><div><p>We present a general protocol for the formal Michael addition of acetone to a,b-unsaturated esters and amides, a transformation difficult to perform using current methods. The protocol comprises of an amidine catalyzed relay ring-opening and fragmentation of 3,4-dihydropyranones. The reaction proceeds under mild conditions, has a broad substrate scope and the products can be isolated in good to excellent yields (30 examples, with up to 97 % yield). The method can be applied to homochiral substrates with total preservation of chiral information, generating products in high optical purity. Kinetic experiments upported by quantum chemical modeling indicates that the reaction is of second order with respect to the catalyst. The kinetic isotope effect has been determined to be 2.3, which supports a mechanism in which the catalyst takes a bifunctional role, acting both as a Brønsted base and as a hydrogen bond donor. The findings presented here enables a rapid entry to compounds previously considered difficult to access and highlights the dual functionality of amidine superbases as catalysts.</p></div></div></div>

Decision Making in Preservation Rhinoplasty: A 100 Case Series With One-Year Follow-Up

Background Preservation rhinoplasty (PR) is a new chapter in rhinoplasty history. The term was coined by Daniel in 2018 and represents a fundamental change in philosophy. Objectives The aim of this study is to discuss a single-surgeon case series utilizing PR techniques. Methods One hundred fifty-three primary rhinoplasty cases were studied retrospectively between December 2016 and August 2017. One hundred cases had at least 1 year of follow-up. Technical details were recorded, including dissection plane, ligament preservation, tip support, lateral crural maneuvers, alar contour grafts, and preservation of the dorsum vs traditional reduction. These 100 cases can be categorized as either complete preservation rhinoplasty (PR-C) or partial preservation rhinoplasty (PR-P). Results All patients had open rhinoplasty and the average follow-up time was 13 months. All patients had preservation of the dorsal soft tissue envelope, and in 36 the entire soft tissue envelope and ligaments were preserved. Fifty-four had preservation of the alar cartilages. Thirty-one had dorsal preservation. The combinations include: PR-C (skin, dorsum, and alars): 24; PR-P (skin and dorsum): 2; PR-P (alars and dorsum): 2; and PR-P (skin and alars): 7. Conclusions In most patients, the dorsal soft tissue envelope and nasal ligaments can be preserved. When possible, the lateral crura should be preserved and tensioning chosen over excision. Dorsal preservation is a versatile technique when proper patient selection is undertaken, and long-term issues with the middle vault and keystone area can be avoided. Some patients will benefit from total preservation where nothing is removed/disrupted and underlying structures are reshaped. Level of Evidence: 4

Late open conversion in ruptured abdominal aortic aneurysm after endovascular repair

Despite technological advances, the long-term outcomes of endovascular aortic aneurysm repair (EVAR) are still debatable. Although most endograft failures after EVAR can be corrected with endovascular techniques, open conversion may still be required. A 70-year-old male patient presented at the emergency unit with abdominal pain. Twice, in the third and fourth years after the first repair, a stent graft had been placed over a non-adhesive portion of the stent graft due to type Ia endoleaks. In the most recent admission, a CT scan showed type III endoleak and ruptured aneurysm sac. On this occasion the patient underwent late open conversion. The failure was repaired with total preservation of the main endovascular graft body and interposition of a bifurcated dacron graft. This case demonstrates that lifelong radiographic surveillance should be considered in this subset of patients. Late open conversion following EVAR of ruptured abdominal aortic aneurysms can be performed safely.