UNASSIGNED: Surgical management of popliteal artery aneurysms has been described for half a century. Long term development of the excluded aneurysm sac in the popliteal segment however remains widely unknown, with only a few small series describing outcomes. Residual aneurysm perfusion has the potential to lead to serious complications.
UNASSIGNED: A 63 year old man presents with skin and soft tissue necrosis of the right calf two years after proximal and distal aneurysm ligation and great saphenous vein bypass for a popliteal artery aneurysm. Computed tomography and magnetic resonance angiography show perfusion of the excluded aneurysm as well as extensive necrosis of the gastrocnemius muscle. Direct angiography of the aneurysm demonstrated retrograde aneurysm perfusion due to insufficient distal ligation with recurrent micro-embolisation to the calf via geniculate arteries. Coiling of the geniculate arteries was performed, plugging the connection to the tibiofibular trunk and embolisation of the aneurysm sac. After the intervention, no flow was seen in the aneurysm sac and the patient made full recovery.
UNASSIGNED: Residual aneurysm sac perfusion can lead to complications long after successful aneurysm exclusion. Follow-up after surgery of popliteal aneurysms should include observation of the excluded aneurysm sac with control of residual blood flow. For persistent sac perfusion, aneurysm enlargement or symptoms, further treatment should be considered. Surgical aspects such as complete transection of the artery after aneurysm ligation or end to end anastomosis of the bypass may be considered, to prevent such complications.

BACKGROUND: Pancreaticoduodenal artery aneurysm (PDAA) is a rare, but fatal disease. However, the association between aneurysm size and the risk of rupture remains unclear. There are many options for therapeutic strategies that should be discussed well because the treatment options are often complicated and highly invasive. However, it remains unclear whether additional endovascular therapy is essential for all patients undergoing bypass surgery. Here, we present a case of triple PDAAs with celiac axis occlusion and spontaneous complete regression of inferior PDAAs (IPDAA) after aneurysmectomy of superior PDAA (SPDAA) and aorto-splenic bypass.
METHODS: A 68-year-old woman presented with one SPDAA and two IPDAAs caused by celiac axis occlusion. Aneurysmectomy for IPDAAs was difficult because of their anatomical location and shape. Therefore, we planned a two-stage hybrid therapy. The patient underwent aorto-splenic bypass and resection of the SPDAA. Follow-up CT was performed to evaluate the IPDAAs before planned endovascular embolization. Spontaneous regression of the IPDAAs and normalized PDA arcade decreased the blood flow in the PDA arcade. The patient is doing well without graft occlusion, and the IPDAAs have completely regressed 7 years after surgery.
CONCLUSIONS: Normalization of hyperinflow to the PDA arcade can lead to the regression of PDAA. Potentially, additional endovascular therapy may not be required in all cases when dilation of the PDA improves. However, more cases must be accumulated to establish criteria for predicting the risks of short- and long-term PDAA ruptures.

We present a successful case of treating an infected popliteal aneurysm in a 71-year-old man who arrived at the emergency department in a septic state, reporting a three-week history of fever, lethargy, general malaise, and pain and swelling in the right popliteal fossa. Previously diagnosed with a sizable right popliteal aneurysm, the patient had undergone endovascular treatment using a Viabahn (WL Gore & Associates, Flagstaff, USA) endoprosthesis two months earlier. His fever and malaise emerged a week following minor surgery for a toe infection (panaritium) on the right foot, leading to subsequent necrotic lymphangitis on the dorsum of the same foot. A PET/CT scan strongly indicated an infection within the aneurysmal sac, while a CT angiography confirmed the integrity of the stent graft without any leaks but revealed a ruptured aneurysm. Urgent surgical intervention was necessary. An extra-anatomical autovenous bypass was conducted, followed by an aneurysm and endograft removal. Subsequently, a vacuum-assisted closure (VAC) system was employed to manage the infected wound post sac extraction. The surgical procedure went smoothly without complications, and following a course of antibiotics, the patient recovered well, eventually being discharged after 50 days.

UNASSIGNED: Takayasu\'s Arteritis (TA) is a rare form of large vessel vasculitis often being apparent late in its progression with features of artery occlusion. Studies comparing endovascular approach with bypass surgeries reveal surgery to be a better option with lesser rates of postoperative restenosis.
METHODS: A 25-year-old female patient presented with dizziness, headache, claudication and paresthesias in the right arm. Her right radial pulse couldn\'t be appreciated and BP on the right brachial artery was unrecordable. BP on her left brachial artery was 160/110 mmHg. CT angiogram demonstrated stenosis in the right subclavian, coeliac and left renal artery. After adequate control of hypertension and ruling out the active phase of TA, she underwent right carotid to subclavian bypass with Polytetrafluoroethylene(PTFE) graft. At 1 year follow up there was significant improvement in her right arm claudication.
CONCLUSIONS: Symptomatic cases of TA need either endovascular angioplasty or surgical intervention to establish reperfusion. Surgery must be done only in the inactive phase of the disease because of the risk of reocclusion. The remission of TA is difficult to predict with clinical findings and ESR values. Oftentimes biopsies taken from the arteries of patients who underwent surgery showed features of active inflammation.
CONCLUSIONS: We recommend all cases of TA to be treated with a course of steroids before planning for surgery irrespective of symptomatology and ESR values. Bypass surgeries with PTFE graft along with preoperative or postoperative steroid therapy result in resolution of ischemic symptoms.

BACKGROUND: Esophagogastric bypass is performed for esophageal strictures. Mucus retention, known as mucocele, sometimes occurs at the stricture oral side of the remnant esophagus. It is often asymptomatic and is expected to be naturally decompressed, but it may cause respiratory failure depending on the case. Herein, we report a case in which we successfully performed thoracoscopic esophageal drainage as emergency airway management due to tracheal compression by a mucocele after esophagogastric bypass for unresectable esophageal cancer with esophagobronchial fistula.
METHODS: A 56-year-old man underwent esophageal bypass surgery for an unresectable esophageal carcinoma with an esophagobronchial fistula following chemotherapy and radiation therapy. Nine months after bypass surgery, he experienced severe dyspnea due to tracheal compression caused by mucus retention on the oral side of the esophageal tumor. We planned thoracoscopic surgery for mucus retention drainage through the right thoracic cavity to secure the airway as an emergency procedure under general anesthesia. Intubation can be performed safely by guiding bronchoscopy in the semi-supine position. Upper esophageal dilation was observed on the cranial side of the azygos arch. We dissected the mediastinal pleura of the upper thoracic esophagus and exposed its wall. A 12-Fr silicone drain was placed in the esophagus through the right chest wall and 120 ml of white fluid was aspirated. He was discharged 9 days after surgery without complications and resumed treatment with an immune checkpoint inhibitor 23 days after surgery. Thereafter, he continued chemotherapy for esophageal cancer, but died of tumor progression and lung metastasis 35 months after bypass surgery and 25 months after thoracoscopic surgery.
CONCLUSIONS: Thoracoscopic esophageal drainage could be performed safely as emergency airway management, shorten the period of discontinuance, and allow cancer treatment to be resumed promptly. We believe that this thoracoscopic procedure is an effective and less invasive method if the percutaneous approach is difficult.

Posterior inferior cerebellar artery (PICA) aneurysms often require cerebral vascular reconstruction for surgical treatment because of their characteristic morphology. Despite its potential complications, the occipital artery-to-posterior inferior cerebellar artery (OA-PICA) bypass is a typical treatment because of its versatility. Although a few cases of intracranial-to-intracranial bypass have been reported, this type of vascular reconstruction is only regarded as an alternative to the OA-PICA bypass because of the uncertainty of bypass feasibility and potential risk of ischemic complications. In this article, we report a case of proximal PICA ruptured aneurysm that was treated with a PICA-to-PICA (PICA-PICA) bypass. A 79-year-old man presented with a chief complaint of sudden, severe headache and disturbances in consciousness. Radiological examination revealed a right proximal PICA fusiform aneurysm. The patient had many systemic disorders such as microscopic polyangiitis and steroid-induced diabetes mellitus that could have caused wound dehiscence and cerebrospinal fluid (CSF) leakage. We performed the PICA-PICA bypass and trapping surgery rather than the OA-PICA bypass to avoid skin problems and CSF leakage. The postoperative course was uneventful, and the patient was discharged on day 64 without any neurological disorders. In comparison with the OA-PICA bypass, the PICA-PICA bypass is less likely to cause CSF leakage and skin complications, although it carries the risk of specific ischemic complications and requires advanced surgical techniques. For some patients with systemic disorders, the PICA-PICA bypass could be an optimal treatment option for proximal fusiform PICA aneurysms rather than as an alternative to the OA-PICA bypass.

BACKGROUND: Aplastic or twiglike middle cerebral artery (Ap/T-MCA) is a rare anomaly characterized by a unilateral MCA occlusion with plexiform vessels that causes hemorrhagic and (less commonly) ischemic strokes. The reasons for this are rarely discussed, and thus optimal treatment for ischemic Ap/T-MCA remains controversial. Here, the authors report a case of Ap/T-MCA with transient ischemic attacks treated by bypass surgery and discuss the mechanism of ischemic development and treatment methods.
METHODS: A 62-year-old hypertensive man with transient, recurrent left hemiparesis visited the authors\' hospital. Magnetic resonance angiography showed proximal occlusion of the right MCA and stenosis in the left MCA. Digital subtraction angiography revealed occlusion of the right MCA and abnormal vascular networks, leading to a diagnosis of Ap/T-MCA with contralateral MCA stenosis. Antiplatelet therapy with aspirin was insufficient, and a superficial temporal artery-MCA bypass was performed. There were no ischemic or hemorrhagic events postoperatively.
CONCLUSIONS: Atherosclerosis seems to have a significant impact on the development of ischemic stroke in patients with Ap/T-MCA, and the presence of coexisting atherosclerotic stenotic vascular lesions outside the Ap/T-MCA site is substantial in its development. Bypass surgery is a promising treatment option for ischemic Ap/T-MCA.

UNASSIGNED: Hereby we describe an instructive patient with cerebellar infarction and a growing aneurysm at the posterior inferior cerebellar artery (PICA), which was not a true cause of infarction.
METHODS: A 50-year-old female presented with dizziness and posterior neck pain at our hospital (Mitaka city, Tokyo, Japan). Diffusion weighted magnetic resonance (MR) images showed cerebellar infarction in the left PICA territory and MR angiography study showed an aneurysm at the origin of the left PICA, which grew in 2 weeks. Since we considered cerebellar infarction was caused by thrombosis from the aneurysm, trapping of the PICA and occipital artery-PICA bypass was performed to prevent recurrent cerebellar infarction and rupture of the aneurysm by neurosurgeons. During the operation, dissection was observed at the distal PICA, which was diagnosed to be the true cause of cerebellar infarction. By the follow-up for 12 months at an outpatient, there was no recurrence of cerebral infarction.
UNASSIGNED: A specimen of the artery showing the findings of dissection was not obtained, and the pathological diagnosis could not be made. It would be controversial whether a surgical procedure presented here was the most optimal.
CONCLUSIONS: This is a first reported case of growing aneurysms and cerebral infarction due to arterial dissection. Even if cerebral infarction is accompanied by growing aneurysms, arterial dissection should be included in the differential diagnoses of a cause of infarction. Posterior cervical pain can be a clue for early appropriate diagnosis in such a case.

UNASSIGNED: Extracranial carotid artery aneurysms are rare. Surgery may be difficult when vessels are tortuous and on a high cervical level. We report two patients whose tortuous extracranial internal carotid artery (ICA) aneurysm located on a high cervical level was successfully treated by ICA ligation and a high-flow bypass using a radial artery (RA) graft between the external carotid- and the middle cerebral artery.
UNASSIGNED: (Case 1) A 47-year-old man suffered a recurrent cerebral infarct despite medical treatment. His right extracranial ICA aneurysm measured 33 mm; it was tortuous and located at a high cervical level. We ligated the ICA after placing a high-flow bypass using an RA graft. The aneurysm was not repaired. (Case 2) A 59-year-old woman noticed pulsatile swelling on her left neck. It was due to an extracranial ICA aneurysm that was large (36 mm), tortuous, and located at a high cervical level. We performed ICA ligation after placing a high-flow bypass using an RA graft without direct aneurysmal repair. Six months after the operation she noted a pulsatile bulge on the left oropharynx. We confirmed recurrence of an aneurysm from retrograde blood flow and performed internal trapping by occluding the distal portion of the ICA aneurysm using an intravascular procedure.
UNASSIGNED: ICA ligation after placing a high-flow bypass with an RA-graft is a technically demanding, but safe procedure to address extracranial ICA aneurysms that are tortuous and located at a high cervical level.

Comparative outcomes of extracranial-to-intracranial (EC-IC) and intracranial-to-intracranial (IC-IC) bypass for complex aneurysm treatment based on rupture status are not well described in the literature. In this study, we compare outcomes of EC-IC and IC-IC bypass for complex intracranial aneurysm treatment based on rupture status.
A prospective neurosurgical patient database was retrospectively reviewed. Sixty-three consecutive patients with aneurysm managed with revascularization were identified between July 2014 and December 2018.
During the study period, 41 patients with aneurysm underwent EC-IC bypass (65%; 24 [58.5%] ruptured, 17 [41.5%] unruptured) and 22 patients with aneurysm underwent IC-IC bypass (34.9%; 13 [59.1%] ruptured, 9 [40.9%] unruptured). Graft spasm occurred in 4 patients (9.8%) in the EC-IC group (all ruptured aneurysms) and all anastomoses were patent on immediate postoperative imaging. Perioperative mortality occurred in 5 patients who underwent EC-IC bypass (12.2%; 3 ruptured, 2 unruptured) EC-IC and 2 patients who underwent IC-IC bypass (9.1%; both ruptured); (P = 0.709). Bypass-related complications occurred only in patients with ruptured aneurysm (2 [8.3%] in the EC-IC group and 0 [0%] in the IC-IC group; P = 0.285). For unruptured aneurysms, the overall complication rate was lower in IC-IC compared with the EC-IC group (P = 0.006). Modified Rankin Scale scores on discharge were significantly lower in IC-IC compared with EC-IC bypass for unruptured aneurysms (P = 0.008). There was a trend for shorter temporary occlusion and hospitalization times and overall better outcomes with IC-IC compared with EC-IC bypass.
Although often considered riskier than EC-IC bypass, IC-IC in situ bypass showd a favorable technical and safety profile for the treatment of complex, unruptured aneurysms.