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Background Hepatic cyst disease is often asymptomatic, but treatment is warranted if patients experience symptoms. We describe our management approach to these patients and review the technical nuances of the laparoscopic approach. Methods Medical records were reviewed for operative management of hepatic cysts from 2012 to 2019 at a single, tertiary academic medical center. Results Fifty-three patients (39 female) met the inclusion criteria with median age at presentation of 65 years. Fifty cases (94.3%) were performed laparoscopically. Fourteen patients carried diagnosis of polycystic liver disease. Dominant cyst diameter was median 129 mm and located within the right lobe (30), left lobe (17), caudate (2), or was bilobar (4). Pre-operative concern for biliary cystadenoma/cystadenocarcinoma existed for 7 patients. Operative techniques included fenestration (40), fenestration with decapitation (7), decapitation alone (3), and excision (2). Partial hepatectomy was performed in conjunction with fenestration/decapitation for 15 cases: right sided (7), left sided (7), and central (1). One formal left hepatectomy was performed in a polycystic liver disease patient. Final pathology yielded simple cyst (52) and one biliary cystadenoma. Post-operative complications included bile leak (2), perihepatic fluid collection (1), pleural effusion (1), and ascites (1). At median 7.1-month follow-up, complete resolution of symptoms occurred for 34/49 patients (69.4%) who had symptoms preoperatively. Reintervention for cyst recurrence occurred for 5 cases (9.4%). Conclusions Outcomes for hepatic cyst disease are described with predominantly laparoscopic approach, approach with minimal morbidity, and excellent clinical results.

Objective: Ascending thoracic aortic aneurysms carry a risk of acute type A dissection. Elective repair guidelines are designed around size thresholds, but the 1-dimensional parameter of maximum diameter cannot predict acute events in small aneurysms. Biomechanically, dissection can occur when wall stress exceeds strength. Patient-specific ascending thoracic aortic aneurysm wall stresses may be a better predictor of dissection. Our aim was to compare wall stresses in tricuspid aortic valve-associated ascending thoracic aortic aneurysms based on diameter.Methods: Patients with tricuspid aortic valve-associated ascending thoracic aortic aneurysm and diameter 4.0 cm or greater (n ¼ 221) were divided into groups by 0.5cm diameter increments. Three-dimensional geometries were reconstructed from computed tomography images, and finite element models were developed taking into account prestress geometries. A fiber-embedded hyperelastic material model was applied to obtain longitudinal and circumferential wall stress distributions under systolic pressure. Median stresses with interquartile ranges were determined. The Kruskal-Wallis test was used for comparisons between size groups.Results: Peak longitudinal wall stresses for tricuspid aortic valve-associated ascending thoracic aortic aneurysm were 290 (265-323) kPa for size 4.0 to 4.4 cm versus 330 (296-359) kPa for 4.5 to 4.9 cm versus 339 (320-373) kPa for 5.0 to 5.4 cm versus 318 (293-351) kPa for 5.5 to 5.9 cm versus 373 (363-449) kPa for 6.0 cm or greater (P ¼ 8.7e-8). Peak circumferential wall stresses were 460 (421-543) kPa for size 4.0 to 4.4 cm versus 503 (453-569) kPa for 4.5 to 4.9 cm versus 549 (430-588) kPa for 5.0 to 5.4 cm versus 540 (471-608) kPa for 5.5 to 5.9 cm versus 596 (506-649) kPa for 6.0 cm or greater (P ¼ .0007).Conclusions: Circumferential and longitudinal wall stresses are higher as diameter increases, but size groups had large overlap of stress ranges. Wall stress thresholds based on aneurysm wall strength may be a better predictor of patient-specific risk of dissection than diameter in small ascending thoracic aortic aneurysms.

OBJECTIVES Ascending thoracic aortic aneurysms (aTAAs) carry a risk of acute type A dissection. Elective repair guidelines are based on diameter, but complications often occur below diameter threshold. Biomechanically, dissection can occur when wall stress exceeds wall strength. Aneurysm wall stresses may better capture dissection risk. Our aim was to investigate patient-specific aTAA wall stresses associated with a tricuspid aortic valve (TAV) by anatomic region. METHODS Patients with aneurysm diameter ≥4.0 cm underwent computed tomography angiography. Aneurysm geometries were reconstructed and loaded to systemic pressure while taking prestress into account. Finite element analyses were conducted to obtain wall stress distributions. The 99th percentile longitudinal and circumferential stresses were determined at systole. Wall stresses between regions were compared using one-way analysis of variance with post hoc Tukey HSD for pairwise comparisons. RESULTS Peak longitudinal wall stresses on aneurysms (n = 204) were 326 [standard deviation (SD): 61.7], 246 (SD: 63.4) and 195 (SD: 38.7) kPa in sinuses of Valsalva, sinotubular junction (STJ) and ascending aorta (AscAo), respectively, with significant differences between AscAo and both sinuses (P < 0.001) and STJ (P < 0.001). Peak circumferential wall stresses were 416 (SD: 85.1), 501 (SD: 119) and 340 (SD: 57.6) kPa for sinuses, STJ and AscAo, respectively, with significant differences between AscAo and both sinuses (P < 0.001) and STJ (P < 0.001). CONCLUSIONS Circumferential and longitudinal wall stresses were greater in the aortic root than AscAo on aneurysm patients with a TAV. Aneurysm wall stress magnitudes and distribution relative to respective regional wall strength could improve understanding of aortic regions at greater risk of dissection in a particular patient.