• Journal of Korean Neurosurgical Society
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• v.40 no.3
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• pp.206-209
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• 2006

Objective : Traditionally, standard access to the posterior fossa was a suboccipital craniectomy. After introducing the technique and benefit of posterior fossa craniotomy, several surgeons have used this procedure to manage various pathologies in posterior fossa in children. Though this approach offers several advantages over conventional suboccipital craniectomy, the elevation of bone flap is not easy in adult because of the irregular contour of inner bone surface and tight adhesion of dura to the skull. The aim of this article is to describe the technical aspects of this approach and to delineate the important landmarks for a safe and quick performance in adult. Methods : We report on our series of twenty-five adult patients who underwent craniotomy for posterior fossa pathologies between 2002 and 2005. The maximal follow-up period was 4 years. Results : None of the patients complained of persistent headache and no CSF leaks have occurred postoperatively. We have encountered only two cases of transient subcutaneous CSF retention after craniotomy. Three-dimensional reconstruction of the CT scan confirmed the well-fitted suboccipital bone contour after craniotomy. And patients were satisfied with the cosmetic results. Conclusion : This method is safer and simpler. It restores normal anatomical planes and improves protection of the contents of the posterior fossa. The authors recommend craniotomy as an alternative method of access to the posterior fossa in all age groups.

• Environmental Mutagens and Carcinogens
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• v.25 no.1
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• pp.25-31
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• 2005

The objective was to use MR imaging to provide a template of posterior fossa development during the late stages in the chick embryos. The MR findings were then correlated with histological data. Fourteen normal formalin-fixed embryonic specimens with a gestational age of 14 to 20 days were examined with 1.5 Tesla unit MRl using a conventional clinical magnet and pulse sequences. The MR findings were correlated with the whole-mount histological specimens. Resolution of the morphological features of posterior fossa development in embryos greater than 14 days gestational age was possible. Development of cerebellum, brain stem, 4th ventricle and bony posterior fossa was documented. In the 14-day-old embryos, a premordial cerebellum was visualized in the enlarged bony posterior fossa, and it covered the the roof of the primitive fourth ventricle. The bony posterior fossa grows at the same rate along the supratentorial skull. The supratentorial skull and the rostral part of the brain grows at the same rate. The cerebellum begins to grow later than the rostral part of the brain. In the 19- to 20-day-old embryos, MRl revealed the rapid development of the cerebellar hemispheres, along with an increase in volume manifested by the more typical mushroom-shaped configuration observed in the newly hatched. At this stage, the cerebellum almost completely filled the posterior fossa and covered the entire fourth ventricle. The brain stem grew steadily, but the volume change was too subtle to evaluate. Features of cerebellar histogeneis were beyond the resolution of MRl. However, there were lots of artifacts in the features of the bony posterior fossa. An MR template of normal posterior fossa development would be useful to avoid confusion of normal development with abnormal development and to identify the expected developmental features when provided the estimated gestational age of a embryo.

• Journal of Korean Neurosurgical Society
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• v.59 no.1
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• pp.52-57
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• 2016

Objective : Many surgeons advocate for watertight dural reconstruction after posterior fossa surgery given the significant risk of cerebrospinal fluid (CSF) leak. Little evidence exists for posterior fossa dural reconstruction utilizing monolayer collagen matrix onlay graft in a non-watertight fashion. Our objective was to report the results of using collagen matrix in a non-watertight fashion for posterior fossa dural reconstruction. Methods : We conducted a retrospective review of operations performed by the senior author from 2004-2011 identified collagen matrix (DuraGen) use in 84 posterior fossa operations. Wound complications such as CSF leak, infection, pseudomeningocele, and aseptic meningitis were noted. Fisher's exact test was performed to assess risk factor association with specific complications. Results : Incisional CSF leak rate was 8.3% and non-incisional CSF leak rate was 3.6%. Incidence of aseptic meningitis was 7.1% and all cases resolved with steroids alone. Incidence of palpable and symptomatic pseudomeningocele in follow-up was 10.7% and 3.6% respectively. Postoperative infection rate was 4.8%. Previous surgery was associated with pseudomeningocele development (p<0.05). Conclusion : When primary dural closure after posterior fossa surgery is undesirable or not feasible, non-watertight dural reconstruction with collagen matrix resulted in incisional CSF leak in 8.3%. Incidence of pseudomeningocele, aseptic meningitis, and wound infection were within acceptable range. Data from this study may be used to compare alternative methods of dural reconstruction in posterior fossa surgery.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.975-982
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• 2021

Objective : The occurrence of posterior fossa teratomas in adulthood is extremely rare. In this study, we aimed to report our experience with two cases of posterior fossa mature teratoma in adults who underwent surgical resection. We also performed a systematic review of published papers available to date. Methods : We retrospectively reviewed the electronic medical records of patients who had onset of posterior fossa teratomas in adulthood at our institute between 1995 and 2020. We evaluated the clinical, radiographic, and pathological features of mature teratomas at the posterior fossa in adulthood. Furthermore, we searched the PubMed, EMBASE, and Web of Science database and reviewed published articles. Results : We found 507 articles on database review; of them, 102 were duplicates and 389 were excluded based on the inclusion criteria. Finally, 16 cases of posterior fossa from the web search and related articles. Subsequently, we added two cases that underwent surgery at our institute. We analyzed a total of 18 cases of mature teratomas. Headache was the most common (55.6%) symptom. The teratomas showed heterogeneous signals on magnetic resonance imaging. Thirteen patients (72.2%) had lesion at midline, five patients (27.8%) had calcification. Surgical resection was performed in all patients. No studies reported recurrence after resection. Conclusion : The occurrence of posterior fossa teratomas in adulthood is difficult to diagnose at the initial stage. Radiographic diagnosis alone can lead to misdiagnosis. Pathological confirmation is essential. Surgical resection is a curative option for posterior fossa teratomas in adulthood.

• Journal of Korean Neurosurgical Society
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• v.57 no.5
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• pp.364-366
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• 2015

Supratentorial dermoid cysts are uncommon to develop in the cavernous sinus. We present a ruptured dermoid cyst of the cavernous sinus extending into the posterior fossa. The patient was a 32-year-old female who complained occipital headache, blurred vision, and tinnitus over 4 years. Brain magnetic resonance (MR) imaging revealed an enhanced tumor in the right cavernous sinus extending into the right temporal base and the posterior fossa with findings of ruptured cyst. Surgical resection was performed, and pathological findings were confirmed to be a dermoid cyst. We report a second case with ruptured dermoid cyst of the cavernous sinus extending into the posterior fossa.

• Journal of Korean Neurosurgical Society
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• v.59 no.3
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• pp.314-318
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• 2016

Posterior fossa is a site next to the middle fossa where arachnoid cyst frequently occurs. Generally, most arachnoid cysts are asymptomatic and are found incidentally in most cases. Although arachnoid cysts are benign and asymptomatic lesions, patients with posterior fossa arachnoid cysts often complain of headaches, gait disturbance, and ataxia due to the local mass effects on the cerebellum. We observed a patient with a posterior fossa arachnoid cyst who had visual symptoms and a headache, but did not have gait disturbance and ataxia. We recommended an emergency operation for decompression, but the patient refused for personal reasons. After 7 days, the patient revisited our hospital in a state of near-blindness. We suspected that the arachnoid cyst induced the hydrocephalus and thereby the enlarged third ventricle directly compressed optic nerves. Compressed optic nerves were rapidly aggravated during the critical seven days; consequently, the patient's vision was damaged despite the operation. Considering the results of our case, it is important to keep in mind that the aggravation of symptoms cannot be predicted; therefore, symptomatic arachnoid cysts should be treated without undue delay.

• Imaging Science in Dentistry
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• v.37 no.1
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• pp.19-26
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• 2007

Purpose : To examine whether the maxillofacial skeletal morphology correlates with the condylar position and the anatomic characteristics of articular eminence using measurements of lateral cephalometric radiographs and individualized sagittal temporomandibular joint (TMJ) tomographs. Materials and Methods : I compared measurements of 202 TMJs of 101 orthodontic patients of Kangnung National University Dental Hospital. 1 used Pearson's correlation for comparison of the measuring values in lateral cephalometric radiographs and individualized sagittal TMJ tomographs. Results : Large occlusal plane angle tendency showed decreased width of posterior eminence slope, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large mandibular plane angle tendency showed decreased superior joint space, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large genial angle tendency showed decreased depth of articular fossa, decreased posterior slope angle of eminence and anterior position of condylar head. Large anterior facial height and large posterior facial height tendency showed increased width of posterior slope of eminence, increased depth of articular fossa, increased posterior slope angle of eminence and posterior position of condylar head. Conclusion : Maxillofacial skeletal morphology has correlation with the anatomic characteristics of TMJ. Individualized sagittal TMJ tomographs can provide useful information for anatomical analysis of TMJ.

• Journal of Korean Neurosurgical Society
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• v.40 no.6
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• pp.441-444
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• 2006

Objective : The goal of this study is to evaluate the clinical results in six patients who underwent surgical decompression for the acute subdural hematomas[ASDH] of posterior cranial fossa. Methods : Six patients [five males and one female] who had undergone surgery for ASDH of posterior cranial fossa between 2000 and 2005, were evaluated retrospectively with regard to clinicoradiological findings and surgical outcomes. The mean age was 45.8 years [range $9{\sim}67\;years$]. Results : Preoperative computed tomography showed ASDH on cerebellar hemisphere in four patients and on midline in two. All patients had the associated lesions such as subarachnoid hemorrhage, epidural or subdural hematoma, intraventricular hemorrhage, contusion or pneumocephalus in supratentorial area. Fracture of occipital bone was noted in two patients. Of the four patients who had 13 to 15 of Glasgow coma scale score at the time of admission, three were deteriorated within 24 hours after trauma. Of these three patients, delayed subdural hematoma developed 1 hour after initial normal CT finding in one patient and increased in thickness in another one. Postoperative outcome showed good recovery in three patients and moderate disability in one. Two patients were expired. Conclusion : This study supports that early diagnosis based on strict observation and prompt surgery in the patients with ASDH in posterior fossa will lead to the best results.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.12
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• pp.710-713
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• 2018

A congenital cholesteatoma is a benign mass formed from the keratinizing stratified squamous epithelium. It usually occurs in young children's anterosuperior part of the middle ear. A congenital cholesteatoma which originates from mastoid temporal bone or expands to posterior cranial fossa is rare. Standard treatment of an intracranial cholesteatoma is surgical removal with craniotomy. A 69-year-old woman was diagnosed with a congenital cholesteatoma of mastoid temporal bone that expanded to the posterior cranial fossa, which was successfully treated with transmastoid marsupialization without craniotomy. This is a first documented case of a congenital cholesteatoma of mastoid temporal bone that expanded to posterior cranial fossa, which was successfully treated with transmastoid marsupialization without craniotomy.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.277-280
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• 2009

Posterior cranial fossa subdural hematomas and extension of the subdural hematoma to the cerebellopontine angle is rarely seen and the concurrent development of acute peripheral facial palsy and the management strategy have not previously been reported in this pathology because of its rarity. We present this case to emphasize that minor head trauma may lead to a posterior cranial fossa hematoma extending to the cerebellopontine angle and cause peripheral facial palsy in patients using aspirin (acetylsalicylic acid). In addition, partial evacuation and waiting for the resorption of the hematoma may help to prevent damage to the 7th and 8th cranial nerves.