Minimally Invasive Hematoma Evacuation Using the MindsEye Expandable Tubular Retractor: A Technical Note.

BACKGROUND: Recent advances in intraoperative neuronavigation and cranial access devices have facilitated an increasing interest in the use of minimally invasive techniques (minimally invasive surgery) to safely treat subcortical lesions via a parafascicular approach. Newly developed expandable retractors, such as the MindsEye system further optimize such approaches. In this technical report, we describe the nuances in minimally invasive surgery parenchymal hematoma evacuation using the MindsEye device. METHODS: After placement of the device, the inner stylet and inner obturator are removed, and the expandable sheath is left in place and secured into place with a Greenberg refractor. The sheath easily dilates to the surgeonss preference with a dial, and the walls of the sheath are composed of a thin, clear, membrane to allow easy visualization of the lesion. We additionally retrospectively reviewed clinical characteristics and outcomes across three patients treated at our facility with spontaneous multicompartment intracranial hematoma using the MindsEye system. RESULTS: We provide a video case demonstrating the use of the MindsEye retractor in a transfrontal parenchymal hematoma evacuation. Successful evacuation with achieved in less than 90 minutes with near total clot removal and resolution of mass effect for all reviewed cases with no patients experiencing procedure-related postoperative decline. CONCLUSIONS: Minimally invasive catheter-based and parafascicular approaches using tubular retractors are increasingly recognized as a viable option in the treatment of subcortical lesions. The MindsEye is the first expandable brain access port designed for removal of deep intracranial lesions. We believe it represents a recent addition in the armament of cranial surgeons.

Asymmetry of the C2 pars interarticularis: a clinical anatomical study with relevance to screw placement.

PURPOSE: Potential asymmetries of the C2 posterior elements pose a problem for the spine surgeon seeking to make the best choice for spinal stabilization while reducing morbidity. METHODS: A digital caliper was used to measure the pars interarticularis height and length on left and right sides of 25 adult C2 vertebrae. The pars interarticularis was defined as the bone between the posterior most aspect of the superior articular process and the anterior most aspect of the inferior articular process of C2. Also, the C2 vertebrae from 49 patients were scanned by CT. Parasagittal images were reviewed and using the same definitions as were used for the skeletal specimens, the length and the height of the C2 pars interarticularis from both the left and right sides were measured using CT. The image slices were acquired at 3 mm intervals. The pars interarticularis height was determined on sagittal CT reconstruction, while the pars interarticularis length was calculated on the basis of the axial images. RESULTS: The lengths and the heights of the left and right pars interarticularis were compared using CTs of patients and skeletal specimens. No significant differences were found in the length and height measurements of the CT images on both sides. However, in the skeletal specimens, the left and right pars interarticularis did not differ significantly in length but differed significantly in height (p = 0.003). The mean height of the left pars interarticularis was approximately two times larger than the right in the skeletal specimens. Absolute differences were calculated between the side with the greater length and height and the side with the lesser length and height irrespective of their left-right orientations. For CT measurements, most differences in length and height between the greater pars interarticularis and lesser pars interarticularis occurred between 0 and 1 mm with each successive disparity interval yielding lower numbers. Skeletal measurements revealed a similar length disparity distribution to the CT measurements. However, height measurements in the skeletal specimens varied widely. Eight pars interarticularis specimens demonstrated a height difference between 0 and 1 mm. No dry bone pars interarticularis specimens demonstrated a height difference between 1 and 2 mm. The pars interarticularis of nine specimens demonstrated a height difference between 2 and 3 mm. Two demonstrated a height difference between 3 and 4 mm. Four demonstrated a height difference between 4 and 5 mm and two demonstrated a height difference greater than 5 mm. The greater pars interarticularis lengths and heights were combined and compared to their lesser counterparts on CT and skeletal measurements. In all measurements of this type, significant differences were found in the pars interarticularis length and height, whether measured through CT or via digital calipers. CONCLUSION: Asymmetry between the left and right C2 pars interarticularis as shown in the present study can alter surgical planning. Therefore, knowledge of this anatomical finding might be useful to spine surgeons.

The Longissimus Capitis Insertion as a Superficial Landmark for the Sigmoid Sinus: An Anatomical Study.

Objective Many external anatomical landmarks have been used for approximating deeper, intracranial structures. Herein, we evaluate the attachment of the longissimus capitis (LC) on the mastoid process as a landmark for the underlying sigmoid sinus. Methods Adult cadavers underwent dissection of the posterior occiput with special attention to the attachment of the LC muscle. Once the periphery of the muscle's tendon of attachment was determined, a burr hole was made in this area and evaluated internally for its relationship to the sigmoid sinus. Results From an intracranial view, burr holes on all sides were over the sigmoid sinus and just slightly lateral to the center of the sinus. The distance from the midline to the medial border of the insertion of the LC had a mean of 63.0 ± 7.2 mm. The width of the tendon of insertion of the LC on the mastoid process had a mean of 17.6 ± 5.7 mm. The length of the tendon insertion of the LC had a mean of 14.7 ± 4.7 mm. The distance from the inferior border of the insertion of the LC to the tip of the mastoid process had a mean of 6.2 ± 4.5 mm. Conclusion To our knowledge, use of the attachment site of the LC on the mastoid process as an external landmark for the underlying sigmoid sinus has not previously been reported. Based on our cadaveric findings, the sigmoid sinus is centered under the attachment of the LC regardless of the width of its tendon.

Review of the Petroclinoid Ligament.

An ossified left petroclinoid ligament was found during routine dissection of the skull base in an adult male cadaver. The petroclinoid ligament is clinically and surgically important given its anatomical relationships to cranial nerves III, V, and VI, so its ossification is a risk factor for injuries due to trauma, increased intracranial pressure, and vascular and tumor compression resulting in abducens and oculomotor palsies. The causes of petroclinoid ligament ossification are yet to be completely elucidated although several reports have associated them with age-related and physiological processes. Assessing the integrity of the petroclinoid ligament is important during skull base surgical interventions to avoid postoperative complications. Therefore, this paper reviews the petroclinoid ligament and its variation, the ossified petroclinoid ligament.

Tilt-table test: its role in modern practice.

Syncope is a major healthcare problem with significant morbidity, mortality and healthcare cost. It is a common symptom with a complex pathophysiology and, therefore, several aetiologies. Tilt-table testing (TTT) is an important, yet perhaps not widely-used, test that forms part of the management of syncope. We sought to assess the utilisation of this test in our institution for the investigation of patients with syncope, to study the referral patterns and the outcomes and usefulness of the TTT in a real-life setting. We undertook a retrospective study of all the TTT that were performed in our institution between January 2009 and October 2009. Of the 69 patients in which TTT was performed, 14 (20%) presented with presyncope, 24 (35%) with a single episode of syncope and 24 (44%) with multiple episodes. The average age was 57.2 years and 64% were female. Of the total patients, 35 (51%) had an abnormal TTT. Of the patients with normal TTT, four had internal loop recorders and six were referred to other medical specialities. The remaining patients (49%) had no formal diagnosis and were referred back to their general practitioner. TTT remains a common test modality and has great value when undertaken in the correct clinical context. This underlines the importance of a detailed clinical history. The European Society of Cardiology guidelines ensure a methodical and rational approach to syncopal patients and aide in choosing the right patient for the right test.

Hydatid cysts of the brain.

BACKGROUND: Brain involvement with hydatid disease occurs in 1-2% of all Echinococcus granulosus infections. Cerebral hydatid cysts are usually supratentorial, whereas infratentorial lesions are quite rare. Objective of the study was to determine the clinical presentation and surgical outcome of cranial hydatidosis. METHODS: This retrospective study was performed in the department of neurosurgery LRH Peshawar from December 2000 to Oct 2007. Twenty one cases with intracranial hydatidosis were operated. The patients were either admitted through OPD or referred from other units. CT and/or MRI were the imaging modalities to reach the diagnosis in addition to serological and haematological tests. Surgery was the only treatment option used. Pericystic hydraulic method was the technique used for the excision of the hydatid cyst of brain. RESULTS: There were 9 males and 12 females with male to female ratio of 1:1.3. All patients belonged to paediatric age group with age range of 3-14 years and mean age of 7.42 +/- 3.2 years. Headache, vomiting, papilloedema were present in all the patients while seizures were the present in 16 patients. The lesion was removed surgically by adopting pericystic hydraulic method during craniotomy in all cases. There was no intra-operative morbidity except that the cyst ruptured in one case. No postoperative complications were noted and there was no mortality. CONCLUSION: Hydatid cyst of the brain presents clinically as intracranial space occupying lesion and is more common in children. Surgery is the treatment option with affordable morbidity and low mortality.

HydroCoil embolization of a ruptured infectious aneurysm in a pediatric patient: case report and review of the literature.

INTRODUCTION: Intracranial infectious aneurysms in the pediatric population are rare. Although surgery has been the traditional treatment of ruptured pediatric infectious aneurysms, endovascular coil embolization has become an attractive alternative due to its low rate of morbidity and mortality. CASE REPORT: A 9-year-old boy with a significant medical history of aortic valve replacement, antibiotic-treated infective endocarditis, and multiple embolic cerebral infarcts presented with a high-grade intraventricular hemorrhage due to the rupture of a large infectious proximal posterior circulation aneurysm. Computed tomography and cerebral angiogram demonstrated a right crural/ambient cistern hematoma and an associated infectious aneurysm of the right proximal posterior cerebral artery. The ruptured infectious aneurysm was coil-embolized with hydrogel-coated platinum coils without sacrifice of the distal parent artery. The aneurysm was completely occluded, and the patient regained all neurological function. CONCLUSION: Ruptured infectious aneurysms in the pediatric population occur despite aggressive medical therapy. Patients with infective endocarditis and embolic infarcts should be followed closely due to the risk of major hemorrhagic events, including aneurysm rupture. Hybrid coil embolization of ruptured infectious aneurysms with preservation of the distal parent artery is exceedingly rare and effective in the management of ruptured infectious aneurysms in the pediatric population.