Pituitary adenoma with adipose tissue: A new metaplastic variant.

Pituitary adenomas are benign tumors representing approximately 15-20% of intracranial neoplasms. There have been few reports of metaplastic osseous transformation and about 60 cases of neuronal metaplasia in pituitary adenoma but adipose metaplasia has not been previously described in the English literature. Here we report a case of pituitary adenoma with metaplastic adipose tissue in a 58-year-old male patient. Histologically this case fulfilled the criteria of a non-functioning pituitary adenoma, and moreover a central area of adipose tissue, made by mature adipocytes, and many tumor cells, containing fat droplet were evident. Lipomatous transformation of tumor cells in the CNS has been previously observed but, to the best of our knowledge, our case is the first pituitary adenoma with such change. The histogenesis of the adipose element in pituitary adenoma is not well understood, and could be a result of a metaplastic change or divergent differentiation from a common progenitor cell.

Granular cell astrocytoma: report of a case and review of the literature.

A 54-year-old man with no remarkable past medical history was referred to our hospital for the appearance of generalized tonic clonic seizures with loss of consciousness, preceded by phosphenes at the right eye. On magnetic resonance imaging, a contrast-enhanced tumor in the left occipital lobe with peripheral edema was noted. He underwent craniotomy, and the entire mass was removed. Microscopic examination revealed infiltrative atypical astrocytes (glial fibrillary acidic protein, GFAP, positive) with discrete borders and granular cytoplasm. Ki-67 labeling index was 40%. The tumor was diagnosed as a high-grade granular cell astrocytoma (GCA). Postoperative radiotherapy combined with temozolomide was administered. GCAs are aggressive lesions and should not to be confused with localized, benign granular cell tumors or with other non neoplastic granular cell changes in the central nervous system (CNS). GCAs are rare tumors. At this time, only 63 supratentorial/ hemispheric cases, including our case, have been reported in literature.

Atypical and malignant meningioma: outcome and prognostic factors in 68 irradiated patients.

Meningiomas account for up to 20 % of all primary intracranial neoplasms; although the majority of these have a benign course, as many as 5-10 % can display more aggressive behavior and a higher incidence of disease progression. The benefit of immediate adjuvant radiotherapy is still being debated for atypical and malignant meningiomas. This study aimed to retrospectively assess prognostic factors and outcome in 68 patients with atypical and malignant meningiomas. Sixty-eight meningioma patients were treated with radiotherapy after initial resection or for recurrence, between January 1993 and December 2011. Surgery was macroscopically complete in 80 % of the patients; histology was atypical and malignant in 51 patients and 17 patients, respectively. Mean dose of radiotherapy was 54.6 Gy. Fifty-six percent of all patients received radiotherapy after surgical resection, 26 % at the first relapse, and 18 % at the second relapse. Median follow-up was 6.7 years, (range 1.5-19.9 years). The 5- and 10-year actuarial overall survival (OS) rates were 74.1 and 45.6 %, respectively. At univariate analysis age >60 years, radiotherapy dose >52 Gy showed statistical significance, (p = 0.04 and p = 0.03, respectively). At the multivariate analysis radiotherapy dose >52 Gy maintained the statistical significance, (p = 0.037). OS of patients treated with radiotherapy at diagnosis was longer than the survival of patients treated with salvage radiotherapy; however this difference did not reach statistical significance when tested for the entire series or for the subgroups of grade 2 and grade 3 patients. The 5- and 10-year disease-free survival (DFS) rates were 76.5 and 69.5 %, respectively, and were significantly influenced by size >5 cm (p = 0.04) and grading (p = 0.003) on univariate analysis. At multivariate analysis, size and grading both remained significant prognostic factors, p = 0.044 and p = 0.0006, respectively. Grade ≤ 2 acute side effects were seen during radiotherapy treatment in 16 % of the patients, with no ≥ grade 3 acute toxicity, based on the Common Terminology Criteria for Adverse Events. In this mono-institutional retrospective study, age and radiotherapy dose were associated with a longer OS, while preoperative size and grading of the tumor influenced DFS. Although there were some advantages in terms of OS for patients treated with postoperative radiotherapy, the benefit did not reach the significance. Multicenter prospective studies are necessary to clarify the management and the correct timing of radiotherapy in such a rare disease.

Predictive potential of pre-operative functional neuroimaging in patients treated with subthalamic stimulation.

PURPOSE: The aim of this study was to investigate the predictive potential of pre-operative regional cerebral blood flow (rCBF) in the pre-supplementary motor area (pre-SMA) and clinical factors in Parkinson's disease (PD) patients treated with subthalamic nucleus (STN) stimulation. METHODS: Ten patients underwent rCBF SPECT and motor Unified Parkinson's Disease Rating Scale (UPDRS) pre- and post-operatively during stimulation at 5 and 42 months. Statistical parametric mapping (SPM) was used to extract rCBF values in the pre-SMA because it is related with motor improvement. Post-operative outcomes included motor response to stimulation and percent improvement in UPDRS. Pre-operative predictors were explored by correlation test, linear regression and multivariate analyses. RESULTS: Higher pre-operative rCBF in the pre-SMA and younger age were associated with favourable outcomes at 5 and 42 months. Pre-operative rCBF results were significantly associated with baseline clinical factors. CONCLUSION: This study shows that PD patients with younger age have higher rCBF values in the pre-SMA and better outcome, thus giving the rationale to the hypothesis that STN stimulation could be considered early in the course of disease.

Lipoastrocytoma: Case report and review of the literature.

Lipoastrocytoma is an extremely rare tumor, with only six cases described. We report the case of an astrocytoma involving the upper part of the cerebellar-pontine angle and the right portion of the clivus starting from the brainstem with a diffuse lipomatous component in a 39 year-old man. The patient was admitted with headache of 1 year's duration and diplopia over the previous 3 months. MRI revealed a ponto-cerebellar lesion that showed irregular enhancement after contrast administration. Subtotal excision of the tumor was accomplished. Adjuvant chemotherapy and radiation therapy were not administered. Histologically the tumor showed the classical histology of low-grade astrocytoma and a portion of the lesion was composed of lipid-laden cells. Immunohistochemistry for glial fibrillary acid and S-100 proteins clearly demonstrated the glial nature of these cells. Ki-67/Mib-1 labeling index was low (2%). The patient remains in good neurological conditions after 10 months. Our case has a benign postoperative behavior, also after subtotal excision, with restrictions due to the short follow-up. It is important to record each new case of this rare tumor to produce a better characterization of this lesion.

Left Deep Frontal Cavernous Angioma Mimicking a Glioma in an Adult Patient.

Cerebral cavernous angiomas are vascular malformations characterized by large adjacent vessels. Usually, these lesions are smaller than 3 cm, the mean age at presentation occurs between 20 and 40 years, and the neuroradiological findings are well described, especially for magnetic resonance imaging, where the "popcorn balls" appearance is due to the presence of locules containing blood. Among these, the giant cavernous angiomas are very rare, particularly in adults. We collected clinical and neuroradiological data from clinical file and hospital diagnostic archive. A comprehensive review of similar cases was performed. We describe the clinical, diagnostic, and surgical management of a giant cerebral cavernous angioma located in the left deep frontal lobe mimicking a high-grade glioma in an adult Chinese patient. Giant cerebral cavernous angioma may be misdiagnosed and should be considered as differential diagnosis.

Cyclooxygenase-2 (COX-2) overexpression in meningiomas: real time PCR and immunohistochemistry.

Cyclooxygenase-2 (COX-2) is the inducible form of the enzyme involved in the first steps of the prostaglandins and thromboxane synthesis. COX-2 up-regulation is demonstrated in tumors where it can modulate tumoral progression, metastasis, multidrug resistance, and angiogenesis. Experimental data suggest a possible therapeutic use of the COX-inhibitors nonsteroidal antiinflammatory drugs (NSAIDs). NSAIDs can block tumor growth through many mechanisms, especially through antiangiogenic and proapoptotic effects. Moreover, NSAIDs can also improve the efficacy of radiotherapy, chemotherapy, and hormonal therapy. This study reviews the COX-2 expression as evaluated through immunohistochemistry and real time polymerase chain reaction (RT-PCR) in 23 meningiomas [14 World Health Organization (WHO) grade I; 5 WHO grade II; 3 WHO grade III; 1 oncocytic meningioma]. At immunohistochemistry all the lesions but 4 (83%) were COX-2 positive. At RT-PCR 9 meningiomas, 8 WHO grade I and 1 WHO grade II, showed a COX-2 expression greater than the reference value (average expression of all meningiomas that we studied). The association between tumor grade and immunohistochemical or RT-PCR COX-2 expression was not significant (P=0.427 and P=0.251, respectively). In conclusion, even if further studies on larger series are necessary, the common COX-2 overexpression in meningiomas may suggest considering the COX-2 inhibitors, alone or in combination with radiotherapy, a potential area of therapeutic intervention in some selected meningiomas.

Merlin expression in secretory meningiomas: evidence of an NF2-independent pathogenesis? Immunohistochemical study.

One of the most common chromosomal regions implicated in the meningiomas tumorigenesis is 22q12 where the neurofibromatosis 2 (NF2) gene resides. The NF2 tumor-suppressor gene encodes for the merlin/schwannomin protein, which is responsible for the inherited disease neurofibromatosis 2. NF2 gene mutations predominantly occur in transitional and fibroblastic meningiomas, whereas the meningothelial variant is less affected. Secretory meningioma is an infrequent meningioma subtype. Its most typical morphologic feature is the presence of intracytoplasmic or extracytoplasmic round hyaline, eosinophilic, and periodic acid Shiff-positive bodies in a lesion frequently otherwise classifiable as meningothelial meningioma. This study reviews the immunohistochemical merlin expression in 14 consecutive secretory meningiomas. Our purpose was to investigate if secretory meningiomas, analogous to meningothelial meningiomas, follow a molecular route of pathogenesis independent of the neurorofibromatosis 2 gene-associated pathway. All meningiomas showed positive immunocoloration involving the majority of the hyaline inclusions and secretory cells; in 12 (86%) meningiomas, a positive immunoreaction was also documented in nonsecretory tumoral cells. Our results may indicate a molecular, besides morphologic, similarity between secretory and meningothelial meningiomas: the almost constant merlin immunohistochemical expression in our series gives evidence for a possible NF2 gene-independent pathogenesis in secretory meningiomas.

Expression of the antiapoptotic gene seladin-1 and octreotide-induced apoptosis in growth hormone-secreting and nonfunctioning pituitary adenomas.

CONTEXT: Seladin-1 (from selective Alzheimer's disease indicator-1) is a recently discovered gene that has been found to be down-regulated in brain regions affected by Alzheimer's disease. Seladin-1 effectively protects neurons against beta-amyloid-mediated toxicity and prevents apoptosis via inhibition of the activation of caspase-3, a key mediator of the apoptotic cascade. Although seladin-1 is expressed in the pituitary gland, no study addressed the expression or the function of this gene in pituitary adenomas. OBJECTIVE: The aim of the present study was to determine the expression level of the seladin-1 gene in pituitary tumors, i.e. GH-secreting and nonfunctioning pituitary adenomas (NFPA), and to determine whether differential expression might be associated with different somatostatin (sst)-induced apoptosis. RESULTS: We found by quantitative real-time RT-PCR that the expression level of seladin-1 was significantly higher in NFPA (n = 21) than in GH-secreting adenomas (n = 30; mean +/- se, 25.69 +/- 6.39 vs. 8.02 +/- 2.68 pg/microg total RNA; P = 0.006). Although the amount of activated caspase-3 did not differ between the two groups of tumors, in primary cell cultures, octreotide was able to increase apoptosis, evaluated by the level of cleaved cytokeratin 18 and the presence of apoptotic nuclei, in GH-secreting adenomas, but not in NFPA. This different response was not attributable to differences in the amount of transcript of sst receptors 2 and 5, which was similar in the two groups of tumors. CONCLUSIONS: Our results suggest that differential seladin-1 expression in pituitary adenomas may be associated with a different apoptotic response to sst analogs.

Brain networks underlying the clinical effects of long-term subthalamic stimulation for Parkinson's disease: a 4-year follow-up study with rCBF SPECT.

UNLABELLED: The motor improvement derived from high-frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) in Parkinson's disease (PD) is maintained over time after surgery. The aim of the present prospective follow-up study was to assess regional cerebral blood flow (rCBF) changes related to such improvement in the long term. METHODS: Ten PD patients with STN-DBS underwent 3 rCBF SPECT studies at rest-once preoperatively in the off-drug condition and the other 2 postoperatively in the off-drug/on-stimulation conditions at 5 +/- 2 and 42 +/- 7 mo. Patients were administered with Unified Parkinson Disease Rating Scale (UPDRS), Hoehn and Yahr (H&Y) scale, and Schwab and England (S&E) scale. Statistical parametric mapping was used to investigate rCBF changes during long-term STN stimulation in comparison with preoperative rCBF and the relationship between rCBF and UPDRS scores was used as a covariate of interest. RESULTS: All patients showed a maximum clinical improvement during the first months after surgery and remained rather stable during further follow-up. The effect of STN-DBS from the pre- to the postoperative condition at 5 mo was to produce rCBF increases in the presupplementary motor area (pre-SMA), premotor (PMC), and dorsolateral prefrontal cortices. From the postoperative condition at 5 mo to that at 42 mo, the STN stimulation produced further rCBF increases in these frontal areas, and also in the primary motor/sensory cortices, globus pallidi, ventral lateral thalamic nuclei, cerebellum, pons, and midbrain entailing the substantia nigra (P < 0.0001). A correlation was detected between the improvement in motor scores and the rCBF increase in the pre-SMA and PMC (P < 0.0001). No correlation was present between the daily consumption of levodopa and the rCBF. CONCLUSION: Our study suggests that the long-term STN stimulation leads to improvement in neural activity in the frontal motor/associative areas. After an rCBF increase during the first months of stimulation, these regions showed a further increment in the later phase, which was accompanied by an increased activity in subcortical structures. The correlation between motor improvement and rCBF increase in higher order motor cortical areas suggests that even in the long term, as well as in the short term, the STN-DBS achieves its therapeutic benefit by restoring the activity within these cortical regions.

Detection of rearrangements in the NF2 gene using semi-quantitative multiplex fluorescent PCR.

Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder that predisposes to the development of bilateral vestibular schwannomas (sometimes associated with schwannomas at other locations), meningiomas, and ependymomas. Point mutations that inactivate the NF2 tumor suppressor gene, located in 22q12, have been found in 45-85% of NF2 patients; in addition, large genomic deletions can be found. To evaluate the presence of genomic NF2 rearrangements, we have developed a fluorescent semiquantitative multiplex PCR method. Briefly, short fragments corresponding to the 17 exons, the promoter region, and the 3' end of the NF2 gene were co-amplified by PCR using dye primers. An additional fragment, corresponding to another gene used as an internal control, was systematically amplified in each multiplex PCR. Initially, we validated the method by using monosomic 22q and trisomic 22 samples. The fluorescent multiplex PCR method was then used to analyze 21 NF2 individuals in which single-strand conformational polymorphism (SSCP) analysis and/or direct sequencing had revealed no NF2 point mutations; we were able to detect two deletions and one duplication in NF2 in 3 patients. In conclusion, the method we developed could easily be applied in detecting NF2 deletions and duplications. Discovering genomic duplications is invaluable because they are probably the most difficult molecular alterations to detect with conventional methods and, as a consequence, might be an underestimated cause of NF2.

New perspectives in the treatment of adult medulloblastoma in the era of molecular oncology.

Medulloblastoma is the most common central nervous system tumor in children, while it is extremely rare in adults. Multimodal treatment involving surgery, radiotherapy and chemotherapy can improve the prognosis of this disease, and recent advances in molecular biology have allowed the identification of molecular subgroups (WNT, SHH, Groups 3 and 4), each of which have different cytogenetic, mutational and gene expression signatures, demographics, histology and prognosis. The present review focuses on the state of the art for adult medulloblastoma treatment and on novel molecular advances and their future implications in the treatment of this disease.

The treatment of adults with medulloblastoma: a prospective study.

PURPOSE: To assess in a prospective trial the value of prognostic factors and the outcome of medulloblastoma in adults. METHODS AND MATERIALS: Patients (> or =18 years) with a histologic diagnosis of medulloblastoma were staged according to Chang et al.'s classification (low risk: T1, T2, T3a, M0, and no residual disease after surgery; high risk: T3b-T4, any M+ or postoperative presence of residual tumor). In low-risk patients, treatment consisted of 36 Gy to the craniospinal axis, supplemented by a local tumor dose of 18.8 Gy (total dose of 54.8 Gy). In high-risk patients, 2 cycles of "up-front chemotherapy" were delivered before the same radiation therapy, followed by maintenance chemotherapy if M1, M2, or M3 disease was present. RESULTS: Over a 12-year period, 36 evaluable patients were enrolled. Progression-free survival (PFS) at 5 years was higher in low-risk patients compared to the high-risk group: 76% +/- 14% (95% confidence interval [CI] = 52%-100%) vs. 61% +/- 11% (95% CI = 42%-87%). Patients with M- disease showed a significantly better outcome than M+ patients, with 75% showing PFS at 5 years vs. 45% (p = 0.01). CONCLUSION: The overall PFS observed is comparable to that obtained in pediatric series and suggests that a more effective therapy must be developed for high-risk patients.

Changes in regional cerebral blood flow caused by deep-brain stimulation of the subthalamic nucleus in Parkinson's disease.

UNLABELLED: The aim of this study was to investigate the effect of deep-brain stimulation of the subthalamic nucleus (STN) on regional cerebral blood flow (rCBF) throughout the entire brain volume in patients with Parkinson's disease and to evaluate which of the brain areas showing an rCBF increase during STN stimulation related significantly to the improvement in motor function. METHODS: Ten consecutive Parkinson's disease patients (6 men, 4 women; mean age +/- SD, 59 +/- 8 y) with bilateral STN stimulators underwent 3 rCBF SPECT examinations at rest: the first preoperatively and the second and third postoperatively (follow-up, 4.8 +/- 1.4 mo) with STN stimulators on and off, respectively. The motor unified Parkinson's disease rating scale, the Hoehn and Yahr disability scale, and the Schwab and England activities-of-daily-living scale were used to evaluate the clinical state under each condition. Statistical parametric mapping was used to investigate rCBF during STN stimulation in comparison with rCBF preoperatively and with STN stimulators off. Also evaluated with statistical parametric mapping was the relationship between rCBF and individual motor scores used as covariates of interest. RESULTS: STN stimulation significantly changed rCBF in the right pre-supplementary motor area (pre-SMA), anterior cingulate cortex, and dorsolateral prefrontal cortex and in the medial Brodmann's area 8 (BA8) as defined in the atlas of Talairach and Tournoux (P < 0.05 corrected for multiple comparisons). The rCBF in these areas increased from the preoperative condition to the stimulators-on condition and decreased again after the stimulators were switched off. A significant correlation was detected between the improvement in motor scores and the rCBF increase only in the right pre-SMA and in the anterior cingulate motor area (P < 0.005, uncorrected). CONCLUSION: According to the topographic organization of the primate STN, our study shows that stimulation of the STN leads to rCBF increases in the motor (pre-SMA), associative, and limbic territories (anterior cingulate) in the frontal cortex. The significant correlation between motor improvement and rCBF increase in the pre-SMA and the anterior cingulate motor area reinforces the hypothesis that STN stimulation in parkinsonian patients can potentiate the cortical areas participating in higher-order aspects of motor control.

Cerebral microarteriovenous malformations: diagnostic and therpeutic features in a series of patients.

BACKGROUND AND PURPOSE: Few collected series of cerebral microarteriovenous malformations (micro-AVMs) have been reported. Our propose was to assess the unique diagnostic and therapeutic challenges posed by these lesions and their influence on outcomes. METHODS: The clinical presentation, diagnostic features, principles of endovascular or surgical treatment, and outcomes for a consecutive series of 10 patients (five male, five female; mean age, 48.8 years; age range, 31-65 years) with angiographically demonstrated cerebral micro-AVMs were retrospectively analyzed. RESULTS: All patients presented with a cerebral hematoma (supratentorial in eight, infratentorial in two, intraventricular in one, subarachnoid in one; mean volume, 11.6 cm(3)), which was superficially situated in nine patients. Neurologic deficits were observed in nine patients, and three patients had seizures. The mean delay between the onset of symptoms and diagnosis was 129.8 days (range, 6 days to 1 year). Superselective angiography was performed in seven patients and followed by successful acrylic embolization of the lesion in five. Five patients underwent surgical intervention, which led to definitive resection. Although long-term neurologic problems were present in eight patients, they were able to return to their previous activities and employment. CONCLUSION: The diagnosis of cerebral micro-AVMs requires a high index of suspicion, especially in young adults with atypical hemorrhaging. Single-shot embolization of micro-AVMs may be a safe alternative to the established surgical therapy in select cases. Outcomes depend mostly on the clinical conditions at admission.

Extraventricular neurocytoma: morphological and immunohistochemical considerations on differential diagnosis.

Neurocytoma is an unusual neuronal tumor especially affecting young people. It commonly arises in the ventricles and has a benign outcome. Herein, we report on a rare case of extraventricular neurocytomas (right parietal lobe) in a young girl admitted to hospital for a cranial trauma subsequent to a seizure. The tumor, radiologically well-circumscribed, cystic and enhancing, was surgically excised. The patient, who received no post surgical treatment, is alive and well after 18 months of follow-up. Pathological examination showed a well-differentiated lesion composed of uniform, round cells with perinuclear halos in a neuropil background and immunohistochemically positive for neuronal markers (synaptophysin, neuron-specific enolase, neurofilaments). The authors emphasize the role of the morphological and immunohistochemical evaluations to recognize this rare tumor.

A case of brain abscess by Eikenella corrodens in a HIV-positive patient.

We report the case of a 61-year-old homosexual male who came to our observation because of a recent onset occipital and left frontoparietal headache, weakness, anorexia, hyperosmia and hypergeusia and psychomotor slowing, apathy and fatuous behavior. This case, besides the old problem of the differential diagnosis of intracranial mass lesions in HIV-positive patients, induces one to examine more closely the relationship between HIV, brain abscesses and Eikenella corrodens. We suspect that the primary infection was in the oral cavity, since HIV-positive patients have a higher incidence of atypical gingivitis and typical periodontitis due, among others, to Eikenella corrodens.

Allergic fungal rhinosinusitis infiltrating anterior skull base and clivus.

Bone erosion and skull base invasion are often suggestive of a malignant mass in paranasal and nasal cavities. Nevertheless, forms of chronic rhinosinusitis, such as allergic fungal rhinosinusitis (AFRS), could mimic malignant features. Here, we report AFRS patient with orbital, anterior cranial fossa, Turkish saddle and clivus erosion. A 48-year-old Caucasian female with history of drug-resistant headache, nasal obstruction and anosmia was referred to our institution. Imaging showed hyperdense featureless tissue with signs of medial orbital wall, cribiform lamina and clivus erosions and encasement of right internal carotid artery. Massive amounts of thick and grayish mucoid material were evacuated during surgery. In case of bony erosion, malignancy should always be excluded. Often the correct diagnosis will be obtained only by operative specimens. AFRS could usually be managed endoscopically. Appropriate medical management of the AFRS should be administered in order to prevent relapses.

Complex repetitive behavior: punding after bilateral subthalamic nucleus stimulation in Parkinson's disease.

"Punding" is the term used to describe a stereotyped motor behavior characterized by an intense fascination with repetitive purposeless movements, such as taking apart mechanical objects, handling common objects as if they were new and entertaining, constantly picking at oneself, etc. As a phenomenon with both impulsive and compulsive features, the phenomenology of punding is currently being questioned. In order to investigate the pathophysiology of this phenomenon, we screened a population of Parkinson's disease (PD) outpatients who underwent subthalamic nucleus deep brain stimulation (STN DBS). We conducted a patient-and-relative-completed survey with 24 consecutive patients in an academic outpatient care center, using a modified version of a structured interview. Patients were administered the Unified Parkinson's Disease Rating Scale (UPDRS), the Obsessive-Compulsive Inventory and the Sheehan Disability Scale. Five (20.8%) of the 24 subjects were identified as punders, including three men (60%) and two women. The punders were comparable to the non-punders in terms of clinical and demographic factors. The punder and non-punder groups only differed statistically with regard to the length of time from DBS implantation. Those findings suggest that punding might be induced by STN DBS, and its rate of occurrence in DBS population seems to be more common than previously suspected.

Ruptured, dissecting posterior inferior cerebellar artery aneurysms: endovascular treatment without parent vessel occlusion.

INTRODUCTION: Treatment of a dissecting aneurysm of the medullary segments of the posterior inferior cerebellar artery (PICA) usually entails trapping of the diseased arterial segment with possible sacrifice of brainstem perforators. The goal of the work was to review our experience with selective coiling of ruptured, dissecting aneurysms of the anterolateral segments of the PICA without parent vessel occlusion. METHODS: Eleven consecutive patients (9 women, 2 men, mean age 47.2 years) were retrospectively reviewed from a prospectively acquired neuroradiological database. On admission three patients had Hunt and Hess (HH) grade I, three HH grade II, two HH grade III, and one HH grade IV. Outcome was evaluated according to the modified Rankin scale (mRS) score. Follow-up (mean:19.4 months) consisted of magnetic resonance angiography and/or digital subtraction angiography in ten patients. RESULTS: Ten patients had mRS score 0 and one mRS score 2. No treatment failure occurred. The aneurysm was completely occluded in seven patients, a neck residue was present in two, and a loose coil mesh was present in two. Recurrence occurred in three patients, and all were successfully retreated for a total of 13 procedures. Procedure-related complications were all without clinical consequences and included a coil perforation in one procedure and stagnant filling of the parent vessel in six procedures. PICA occlusion did not occur in any patient. CONCLUSION: Coiling of ruptured, isolated dissecting aneurysms of the PICA without parent vessel occlusion is feasible, relatively safe and effective in preventing early/medium-term rebleeding. A strict angiographic follow-up program is, however, necessary to detect recurrence.