Jung Yong Ahn, Young Sun Chung, and Byung-Hee Lee
Eui Hyun Kim, Jung Yong Ahn, and Sun Ho Kim
The transcranial approach has been the standard technique for removal of craniopharyngiomas for several decades. However, many reports of successful suprasellar craniopharyngioma removal accomplished using extended transsphenoidal surgery (TSS) have recently been published. In the present study, the authors describe their technique and the outcomes of removal of suprasellar craniopharyngiomas aided by the use of an operating microscope and an endoscope concurrently during extended TSS.
Between 1999 and 2008, 18 patients with suprasellar craniopharyngiomas underwent TSS. Tumors that adhered to the optic nerve were safely dissected, and fine perforating vessels were precisely preserved with the aid of a magnified, detailed microscopic view. Portions of the tumor that could not be properly visualized with the microscope were visualized with the endoscope.
Total resection was achieved in all patients, and all visual symptoms improved. Preoperative hypopituitarism improved in 2 patients but persisted postoperatively in 15 patients (hormonal outcome was not available in 1 patient). Diabetes insipidus was present in 16 patients postoperatively. Cerebrospinal fluid leakage developed in 3 patients in the conventional fascia lata graft group, whereas no CSF leakage occurred after the dural suture technique with a fascia lata graft was introduced. This technique could be more precisely applied when using a microscopic view. Tumor recurrence was documented for 1 patient 2 years after surgery.
The authors achieved good results by using extended TSS for the removal of suprasellar craniopharyngiomas. Endoscopy-assisted microscopic extended TSS harnesses the advantages of a microscope as well as those of an endoscope. Surgeons should consider using the advantages of both surgical modalities to achieve the best result possible.
Report of two cases
Jung Yong Ahn, Seong Oh Kwon, Moon Soo Shin, Jin Yang Joo, and Tai Sung Kim
✓ Idiopathic trigeminal sensory neuropathy is a clinically benign disorder in which the main feature is facial numbness limited to the territory of one or more divisions of the trigeminal nerve; the disorder persists for a few weeks to several years, and no underlying disease can be identified. Magnetic resonance (MR) imaging findings are occasionally consistent with a small trigeminal neuroma of the left gasserian ganglion associated with idiopathic trigeminal sensory neuropathy. The authors report on two patients who were treated using a skull base approach in which the gasserian ganglion was exposed and the lesion was removed. The pathological diagnosis was chronic granulomatous neuritis. The authors conclude that, in patients with MR findings suggestive of a small trigeminal neuroma, benign idiopathic trigeminal sensory neuropathy should also be considered in the differential diagnosis. A conservative approach featuring sequential MR imaging studies may avoid an unnecessary surgical exploration.
Jun Hyung Cho, Jung Yong Ahn, Sung Uk Kuh, Dong Kyu Chin, and Young Sul Yoon
Keun Young Park, Jung Yong Ahn, Jae Whan Lee, Jong Hee Chang, and Seung Kon Huh
Vascular complications, including vessel occlusion and hemorrhage, can arise after radiosurgery; however, hemorrhage due to a ruptured de novo aneurysm after Gamma Knife radiosurgery (GKS) for tumor is extremely rare. To the authors' knowledge, only a single case of de novo aneurysm formation after GKS for vestibular schwannoma has been previously reported. In this study, they describe their experience with the treatment of a 74-year-old woman with subarachnoid hemorrhage limited to the cerebellopontine cistern, who had undergone GKS for vestibular schwannoma 5 years earlier. Cerebral angiography demonstrated a left distal anterior inferior cerebellar artery aneurysm; coil embolization was attempted and failed. However, self-resolution of the aneurysm was revealed on follow-up angiography.
Eui Hyun Kim, Se Hoon Kim, Jin Mo Cho, Jung Yong Ahn, and Jong Hee Chang
The authors report a case of IgG4-related hypertrophic pachymeningitis that involved cerebral parenchyma. The mass was removed surgically. Histopathological studies showed diffuse infiltration of lymphoplasmacytic cells without evidence of Langerhans histiocytes or meningothelial cells. Immunoglobulin G4 was strongly positive on immunohistochemical staining. The Gd-enhanced lesion deep inside brain parenchyma was completely resolved after 3 months of oral corticosteroid medication. A nodular type of hypertrophic pachymeningitis that mimics a meningioma is rare. Nevertheless, preoperative presumption is very important, and immunohistochemical studies for IgG4 may be helpful in the differential diagnosis.
Keun Young Park, Jung Yong Ahn, Jun Hyung Cho, Young Chul Choi, and Kyu Sung Lee
✓Neuromyelitis optica (NMO) is a severe demyelinating syndrome defined principally by its tendency to affect optic nerves and the spinal cord selectively. Asymptomatic brain lesions have recently become a common finding in NMO, and symptomatic brain lesions do not exclude the diagnosis of this entity. The authors describe the case of a 12-year-old girl suffering from an unusually atypical form of NMO in which a brainstem lesion was mistaken for a brainstem glioma. Brainstem involvement in NMO exhibits variable features on neuroimaging and is confused with brainstem glioma in cases of extensive brainstem involvement in childhood. Careful differential diagnosis and proper treatment are vital for a favorable prognosis.
Tae Seok Jeong, Seong Son, Sang Gu Lee, Yong Ahn, Jong Myung Jung, and Byung Rhae Yoo
The object of this study was to compare, after a long-term follow-up, the incidence and features of adjacent segment disease (ASDis) following lumbar fusion surgery performed via an open technique using conventional interbody fusion plus transpedicular screw fixation or a minimally invasive surgery (MIS) using a tubular retractor together with percutaneous pedicle screw fixation.
The authors conducted a retrospective chart review of patients with a follow-up period > 10 years who had undergone instrumented lumbar fusion at the L4–5 level between January 2004 and December 2010. The patients were divided into an open surgery group and MIS group based on the surgical method performed. Baseline characteristics and radiological findings, including factors related to ASDis, were compared between the two groups. Additionally, the incidence of ASDis and related details, including diagnosis, time to diagnosis, and treatment, were analyzed.
Among 119 patients who had undergone lumbar fusion at the L4–5 level in the study period, 32 were excluded according to the exclusion criteria. The remaining 87 patients were included as the final study cohort and were divided into an open group (n = 44) and MIS group (n = 43). The mean follow-up period was 10.50 (range 10.0–14.0) years in the open group and 10.16 (range 10.0–13.0) years in the MIS group. The overall facet joint violation rate was significantly higher in the open group than in the MIS group (54.5% vs 30.2%, p = 0.022). However, in terms of adjacent segment degeneration, there were no significant differences in corrected disc height, segmental angle, range of motion, or degree of listhesis of the adjacent segments between the two groups during follow-up. The overall incidence of ASDis was 33.3%, with incidences of 31.8% in the open group and 34.9% in the MIS group, showing no significant difference between the two groups (p = 0.822). Additionally, detailed diagnosis and treatment factors were not different between the two groups.
After a minimum 10-year follow-up, the incidence of ASDis did not differ significantly between patients who had undergone open fusion and those who had undergone MIS fusion at the L4–5 level.
So-Hyang Im, Moon Hee Han, Bae Ju Kwon, Jung Yong Ahn, Cheolkyu Jung, Sung-Hye Park, Chang Wan Oh, and Dae Hee Han
Considerable confusion exists in the literature regarding the classification of cerebrovascular malformations and their clinical significance. One example is provided by the atypical developmental venous anomaly (DVA) with arteriovenous shunt, because it remains controversial whether these lesions should be classified as DVAs or as atypical cases of other subtypes of cerebrovascular malformations. The purpose of this study was to clarify the classification of these challenging vascular lesions in an effort to suggest an appropriate diagnosis and management strategy.
The authors present a series of 15 patients with intracranial vascular malformations that were angiographically classified as atypical DVAs with arteriovenous shunts. This type of vascular malformation shows a fine arterial blush without a distinct nidus and early filling of dilated medullary veins that drain these arterial components during the arterial phase on angiography. Those prominent medullary veins converge toward an enlarged main draining vein, which together form the caput medusae appearance of a typical DVA.
Based on clinical, angiographic, surgical, and histological findings, the authors propose classifying these vascular malformations as a subtype of an arteriovenous malformation (AVM), rather than as a variant of DVA or as a combined vascular malformation.
Correct recognition of this AVM subtype is required for its proper management, and its clinical behavior appears to follow that of a typical AVM. Gamma Knife radiosurgery appears to be a good alternative to resection, although long-term follow-up results require verification.
Young-Hoon Kim, Young Jin Lee, Jung Ho Han, Soyeon Ahn, Jaebong Lee, Jae Hyoung Kim, Byung Se Choi, Jae Seung Bang, Chae-Yong Kim, Gyojun Hwang, O-Ki Kwon, and Chang Wan Oh
The authors aimed to assess whether the prevalence of intracranial aneurysms in patients with intracranial meningiomas was higher than that in a healthy population.
The authors performed a hospital-based case-control study of 300 patients with newly diagnosed intracranial meningiomas and 900 age- and sex-matched controls without a history of brain tumors to evaluate any associations between intracranial aneurysms and intracranial meningiomas. Unconditional multivariate logistic regression models were used for case-control comparisons.
Intracranial aneurysms were identified in 23 patients (7.7%) and 24 controls (2.7%; p < 0.001). There was a significant association between intracranial aneurysms and intracranial meningiomas (OR 2.913, 95% CI 1.613–5.261) and hypertension (OR 1.905, 95% CI 1.053–3.446). In a subgroup analysis of the patients with newly diagnosed intracranial meningiomas, there was a significant association between intracranial aneurysms and hypertension (OR 2.876, 95% CI 1.125–7.352) and tumor volume (OR 1.012, 95% CI 1.001–1.024). These patients were also more likely than controls to have other intracranial vascular diseases (p < 0.001), such as isolated occlusion of the intracranial vessels, excluding intracranial aneurysms.
The prevalence of intracranial aneurysms was higher in patients with intracranial meningiomas. Hypertension and tumor volume appear to be associated with the formation of intracranial aneurysms in these patients.