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Concept: Sebaceous cyst


Trichilemmal cyst, also known as “pilar cyst,” is a benign cyst containing keratin and its breakdown products with a wall resembling external root sheath of hair. It occurs mostly in females as a solitary firm nodule over scalp. Occurrence of multiple trichilemmal cysts in areas other than scalp is extremely rare. We are reporting a case of a 40-years-old female who presented with multiple calcified trichilemmal cysts in multicentric distribution associated with alopecia universalis. Similar complaints were present in elder sister of the patient, indicating a genetic background. Multicentric distribution of trichilemmal cysts, calcification, familial occurrence, and association with alopecia universalis seen in our case are all rare and intriguing features.

Concepts: Family, Female, Gamete, Sebaceous cyst, Cyst, Sibling, Trichilemmal cyst


Splenic tumors are rare and are either primary or secondary, benign or malignant. Most have none to minimal symptomatology and are found incidentally. Splenic cysts can be infectious, congenital, or traumatic. Epidermoid cysts and parasitic cysts are examples of primary cysts and usually have a classic presentation on imaging. Despite advanced imaging modalities and patient’s clinical presentation, it can be difficult to diagnose an epidermoid cyst without histological examination. The purpose of this paper is to discuss typical findings of primary splenic cysts on imaging, but how they may differ in appearance.

Concepts: Cancer, Medical terms, School terminology, Histology, Spleen, Sebaceous cyst, Cyst, Epidermoid cyst


Abstract Intraosseous epidermoid inclusion cysts of the phalanx of the finger are rare, and are regarded as reactive or post-traumatic pseudotumours. We describe a case of an epidermoid cyst in the distal phalanx of the fifth finger caused by chronic nail biting, which was successfully excised.

Concepts: Sebaceous cyst, Epidermoid cyst, Finger, Hand, Nail, Thumb, Distal phalanges


BACKGROUND: Scalp dermoid cysts are subcutaneous sacs lined with a stratified squamous epithelium containing developmentally mature ectodermal tissues, including skin, hair follicles, sweat glands, and sebaceous glands. METHODS: Because they consist of developmentally mature tissues, scalp dermoid cysts are generally benign. Typically, cysts are limited to an extracranial location, and management generally involves simple surgical resection. DISCUSSION: Because of the potential for intracranial and/or intradural extension associated with some scalp dermoids, however, a comprehensive clinical evaluation incorporating MRI and CT imaging is included in the diagnostic process.

Concepts: Skin, Squamous cell carcinoma, Squamous epithelium, Sebaceous cyst, Epithelial cells, Dermoid cyst, Hair follicle, Sebaceous gland


Intracranial epidermoid cysts are uncommon lesions with typical radiological and operative findings. We report a midline cystic lesion in the pre-pontine cistern, with radiological features of an epidermoid, but intra-operatively yielding a thin-walled cyst with fluid contents. The cyst wall showed stratified squamous epithelium on histopathology.

Concepts: Squamous cell carcinoma, Squamous epithelium, Sebaceous cyst, Epithelial cells, Cyst, Epidermoid cyst


BACKGROUND: The relationship between meniscal tears and parameniscal cyst formation is contentious. We investigated whether the development of a parameniscal cyst is related to the size of the meniscal tear by using magnetic resonance imaging (MRI). METHODS: On the basis of a retrospective review of an MRI database, we identified parameniscal cysts in 34 patients with adjacent meniscal tears extending to the meniscocapsular junction. The size of the meniscal tear was measured by dividing the length of the tear along two axes: circumferential and radial. We compared parameters, such as the size of the meniscal tear, the location of the tear, the pattern of each tear, and any associated ligamentous injury and intra-articular lesion, between the 34 patients and the 30 control patients who only had meniscal tears with torn components extending to the meniscocapsular junction. RESULTS: Compared with the controls, patients with parameniscal cysts had significantly larger meniscal tears along the circumferential axis (P<0.001). A critical size of the meniscal tear along the circumferential axis of 12mm was associated with the formation of a parameniscal cyst. CONCLUSIONS: A larger meniscal tear extending into the meniscocapsular junction is more likely to be associated with the occurrence of a parameniscal cyst. The critical size of the meniscal tear, 12mm along the circumferential axis as identified using MRI, is a discrimination value for parameniscal cyst formation. Level of Evidence: Level III.

Concepts: Nuclear magnetic resonance, Magnetic resonance imaging, Sebaceous cyst


Epidermoid cysts account for approximately 1% of all intracranial tumors. Hemorrhage into an epidermoid cyst is extremely rare, and has only been reported a few times. To our knowledge, there are no reports of a hemorrhagic epidermoid cyst presenting with a first generalized tonic clonic seizure. We present a 68-year old female with an epidermoid cyst with intracystic hemorrhage who presented with a first time generalized tonic clonic seizure. When complicated with hemorrhage, the diagnosis of an epidermoid cyst is challenging and there is a potential for misdiagnosis.

Concepts: Time, Medical signs, Sebaceous cyst, Epidermoid cyst, Myoclonus, Seizure types


BACKGROUND: Endosonography (EUS)-guided transmural pseudocyst drainage is a multistep procedure currently performed with different “off-the-shelf” accessories developed for other applications. Multiple device exchanges over-the-wire is time consuming and risks loss of wire access. This report describes the technical feasibility and outcomes for EUS-guided drainage of pancreatic fluid collections using a novel exchange-free device developed for translumenal therapy. METHODS: Between April and November 2010, 14 patients (9 men; mean age, 49.9 years) with pancreatic fluid collection (mean size, 102 mm) underwent 16 EUS-guided drainage procedures using the exchange-free access device at a single tertiary care center. The trocar of the exchange-free device was used to gain pseudocyst access. The dual-balloon catheter then was advanced over the trocar, followed by inflation of the (first) anchor balloon. Cyst contents were sampled, and contrast was injected to define the pseudocyst anatomy. The first guidewire was inserted into the cyst cavity. The cystenterostomy tract was dilated to 10 mm with the (second) dilation balloon, followed by a second guidewire insertion. The exchange-free access device was removed, leaving the two guidewires in place for two double-pigtail stents. RESULTS: The procedure was technically successful for all the patients. No acute procedure-related complications occurred. Late complications included a symptomatic leak in a patient who underwent drainage of a pancreatic uncinate pseudocyst from the second duodenum, a self-limited transfusion-dependent bleed after transbulbar drainage, and symptomatic pseudocyst infection. CONCLUSION: Pseudocyst access, cystenterostomy tract dilation, and placement of two guidewires for dual stent drainage are technically feasible using an exchange-free access device. The device has the potential to standardize, simplify, and streamline EUS-guided pseudocyst drainage with a single instrument. Comparative studies with alternative tools and methods for pseudocyst drainage are warranted.

Concepts: Stent, Tertiary referral hospital, Sebaceous cyst, Cyst, Pancreatic pseudocyst, Pseudocyst, Dilation


Rathke’s cleft cysts (RCC) are benign lesions that originate from remnants of Rathke’s pouch. They can compress adjacent structures causing visual loss and endocrine dysfunction. The endoscopic endonasal transsphenoidal approach (EETA) has gained popularity in the surgical management of pituitary and parasellar tumors. However, postoperative cyst recurrence and endocrine dysfunction are still major concerns. A retrospective chart review was performed on 11 patients who underwent a purely EETA. Subtotal resection of the cyst wall with drainage of the intracystic contents followed by obliteration of the cyst with a fat graft was performed in all patients. Two patients underwent repeated surgeries for symptomatic cyst recurrence. One patient ultimately underwent extracapsular removal of the entire cyst wall because of multiple recurrences after simple drainage. There were no incidences of new permanent hypopituitarism, visual deficits, or postoperative cerebrospinal fluid leaks. All patients reported an improvement of initial preoperative symptoms. A non-aggressive strategy of partial cyst wall removal and simple drainage of cyst contents via EETA is a viable approach for surgical treatment of RCC with a low rate of postoperative endocrine and visual complications. A more aggressive strategy of extracapsular removal of the cyst wall may be indicated in patients with repeated recurrence.

Concepts: Neuroendocrinology, Sebaceous cyst, Anterior pituitary, Spontaneous cerebrospinal fluid leak, Rathke's pouch, Rathke's cleft cyst


The ankyrin repeat and sterile α motif (SAM) domain-containing six gene (Anks6) is a candidate for polycystic kidney disease (PKD). Originally identified in the PKD/Mhm(cy/+) rat model of PKD, the disease is caused by a mutation (R823W) in the SAM domain of the encoded protein. Recent studies support the etiological role of the ANKS6 SAM domain in human cystic diseases, but its function in kidney remains unknown. To investigate the role of ANKS6 in cyst formation, we screened an archive of N-ethyl-N-nitrosourea-treated mice and derived a strain carrying a missense mutation (I747N) within the SAM domain of ANKS6. This mutation is only six amino acids away from the PKD-causing mutation (R823W) in cy/+ rats. Evidence of renal cysts in these mice confirmed the crucial role of the SAM domain of ANKS6 in kidney function. Comparative phenotype analysis in cy/+ rats and our Anks6(I747N) mice further showed that the two models display noticeably different PKD phenotypes and that there is a defective interaction between ANKS6 with ANKS3 in the rat and between ANKS6 and BICC1 (bicaudal C homolog 1) in the mouse. Thus, our data demonstrate the importance of ANKS6 for kidney structure integrity and the essential mediating role of its SAM domain in the formation of protein complexes.Kidney International advance online publication, 3 June 2015; doi:10.1038/ki.2015.122.

Concepts: Kidney, Gene, Mutation, Evolution, Rat, Polycystic kidney disease, Mouse, Sebaceous cyst