The Microcisternal Drainage Technique

BACKGROUND: Microsurgical dissection of arachnoid cisterns requires a combination of anatomic knowledge and microsurgical skill. The latter relies on experience and microsurgical dexterity, which depend on visual identification of cisternal microvasculature. We describe a novel standardized operative sequence to allow for bloodless arachnoid dissection when cisternal anatomy is challenging. METHODS: We used the reported technique in 1928 cases over the past 5 years (2018-2022). The outer arachnoid was incised to enter the cisternal space. A cotton pledget was placed in contact with an inner membrane and gently pushed laterally and superficially with the suction cannula at medium suction power. When the arachnoid membranes dried, arachnoid trabeculae were cut and microvasculature were released at the convexity of their loops and gently transposed off the dissection trajectory. The same principle was used to release parent and perforating arteries from the aneurysm dome. RESULTS: The microcisternal drainage technique enabled safe and efficient access through adhered arachnoid in all cases. A complex anterior communicating artery aneurysm in a 52-year-old lady demonstrated the use of the microcisternal drainage technique during access through the pericallosal cistern. This technique was used in all cases where cisternal dissection was needed. CONCLUSIONS: The microcisternal drainage technique uses deliberate and strategic suction, dynamic retraction, and nuanced scissor cuts to enable precise and bloodless microdissection of adherent arachnoid cisterns. This technique combines common neurosurgical maneuvers in a novel standardized sequence to improve efficiency and safety during arachnoid dissection

High Cervical Carotid Endarterectomy–Outcome Analysis

Objective Carotid endarterectomy (CEA) for high cervical internal carotid artery stenosis is considered to be technically demanding because of the difficulty in dissecting the distal end. We report the surgical technique and outcome analysis of CEA for high cervical lesions. Methods We retrospectively analyzed the records of 98 patients treated by CEA from December 2013 to June 2018. The plaque positions rostral to the C2 vertebral level was defined as the high cervical lesions (n = 34). The surgical technique is to successfully expose the distal end, as follows: 1) extend the skin incision; 2) expose the great auricular nerve maximally; 3) dissect between the SCM and parotid gland fascia; 4) resect the internal deep cervical lymph nodes; and 5) retract the digastric muscle, hypoglossal nerve, and occipital artery. Results There were 8 cases (high cervical group, 4 cases; non-high cervical group, 4 cases) of postoperative diffusion-weighted imaging high signal and 6 cases (high cervical group, 3 cases; non-high cervical group, 3 cases) of symptomatic ischemic lesion. Four cases belonged to the technique-related cerebral infarction group and 4 cases to the perioperative-related cerebral infarction (PRCI) group. High cervical lesion is not considered to be a risk factor for either PRCI (P = 0.610) or technique-related cerebral infarction (P = 0.610). The difference of the diastolic blood pressure between the preoperative period and the second postoperative day showed a risk factor of PRCI (P = 0.033). Conclusions The surgical outcomes for high cervical lesions are equivalent to that of non-high cervical lesions. Excessive blood pressure management from the early postoperative days is a risk of PRCI.Peer reviewe

Retrograde Suction Decompression for Clip Occlusion of Internal Carotid Artery Communicating Segment Aneurysms

BACKGROUND: Retrograde suction decompression (RSD) can achieve proximal parent vessel control, improve aneurysm neck visualization, and allow parent vessel reconstruction for direct clipping of internal carotid artery (ICA) aneurysms. The aim of the present study was to describe the technique and surgical results of RSD for direct clipping of ICA communicating segment (C1) aneurysms. METHODS: The clinical data and treatment summaries of 20 patients who underwent RSD-assisted clipping of ICA C1 aneurysms were retrospectively reviewed. Pre- and postoperative three-or four-dimensional computed tomography angiograms, postoperative magnetic resonance images, surgical notes, operative complications, and outcomes were assessed. RESULTS: All patients except one harbored unruptured C1 aneurysms. Extracranial-intracranial graft bypass using the radial artery was performed in five patients. Fifteen patients required temporary clipping of the posterior communicating artery for further reduction of blood back-flow into the aneurysm. All aneurysms were successfully clipped and postoperative three-or four-dimensional computed tomography angiography revealed no major branch occlusion or residual aneurysm. At the 6-month follow-up examination, 19 patients had a good outcome and 1 patient had poor outcome associated with anterior choroidal artery ischemia. No death had occurred at 6-month follow-up examination. CONCLUSIONS: The RSD technique is a useful procedure to achieve proximal vascular control, to soften and shrinkage the aneurysm sac, and to provide a wide and clean operative field allowing safe clip placement. The RSD technique requires special attention to the relationship between the perforators and the aneurysm, and close cooperation between the surgeon and the assistant.Peer reviewe

Microsurgical resection of unruptured cerebellar arteriovenous malformation presenting with trigeminal neuralgia

Cerebellar arteriovenous malformations (AVMs) represent 10%–15% of all intracranial AVMs and are associated with a greater risk for hemorrhagic presentation compared with supratentorial AVMs. When they reach the cerebellopontine angle cistern, neurovascular compression syndromes, including trigeminal neuralgia and hemifacial spasm, can occur. Due to the aggressive natural history of cerebellar AVM, an effective treatment strategy is required. In this video, the authors demonstrate the technical nuances of microsurgical resection of an unruptured cerebellar AVM in a 24-year-old female presenting with trigeminal neuralgia. The patient underwent right retrosigmoid craniotomy and complete resection of the AVM with resolution of trigeminal neuralgia. The video can be found here: https://youtu.be/6GmNjgFQwx

Toward a more rationalized use of a special technique for repair of frontal air sinus after cerebral aneurysm surgery: The most effective technique

A craniotomy that passes through the frontal air sinus (FAS) often results in postoperative complications such as infection, cerebrospinal fluid leakage or mucocele formation. A good understanding of FAS reconstruction can decrease the morbidity rate of complications. This study describes the outcomes of treatment and establishes the most effective technique for FAS reconstruction in our institution. We enrolled 107 patients who had a bifrontal craniotomy which exposed the FAS during the operation for an anterior communicating artery (ACoA) aneurysm. Demographic data including the follow-up information were collected and analyzed. The complications after surgery were observed and described in the treatment procedure. The patency of the nasofrontal outflow tract (NFOT) was proved by removal of blood clots and bone dust by irrigation and by direct inspection under a microscope before closure of the frontal sinus mucosa with a monofilament non-absorbable 7/0 material suture. The dura was closed in a watertight fashion and an abdominal fat graft was packed into the FAS cavity. There were 33 male and 74 female patients and the mean age (range) was 64 years (32–90 years). The mean follow-up time was 13 months (1–35 months) and complications were found in only 2 patients. One patient suffered from dislocation of the fat graft and the other patient developed a surgical wound infection. At post-operation the first patient sneezed several times and the second patient suffered from trauma in the nasal area after discharge to home. Both patients were surgically treated and cured. In conclusion, FAS reconstruction from our technique is very effective for the prevention of complications after bifrontal craniotomy. Direct suturing of the frontal sinus mucosa and proving the patency of the NFOT are keys to successful treatment